_ 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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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 ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
  33 use ln::channel::{ACCEPTED_HTLC_SCRIPT_WEIGHT, OFFERED_HTLC_SCRIPT_WEIGHT};
  34 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  35 use chain::transaction::OutPoint;
  36 use chain::keysinterface::SpendableOutputDescriptor;
  37 use util::logger::Logger;
  38 use util::ser::{ReadableArgs, Readable, Writer, Writeable, WriterWriteAdaptor, U48};
  39 use util::sha2::Sha256;
  40 use util::{byte_utils, events};
  41
  42 use std::collections::{HashMap, hash_map};
  43 use std::sync::{Arc,Mutex};
  44 use std::{hash,cmp, mem};
  45
  46 /// An error enum representing a failure to persist a channel monitor update.
  47 #[derive(Clone)]
  48 pub enum ChannelMonitorUpdateErr {
  49         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  50         /// to succeed at some point in the future).
  51         ///
  52         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  53         /// submitting new commitment transactions to the remote party.
  54         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  55         /// the channel to an operational state.
  56         ///
  57         /// Note that continuing to operate when no copy of the updated ChannelMonitor could be
  58         /// persisted is unsafe - if you failed to store the update on your own local disk you should
  59         /// instead return PermanentFailure to force closure of the channel ASAP.
  60         ///
  61         /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
  62         /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
  63         /// to claim it on this channel) and those updates must be applied wherever they can be. At
  64         /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
  65         /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
  66         /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
  67         /// been "frozen".
  68         ///
  69         /// Note that even if updates made after TemporaryFailure succeed you must still call
  70         /// test_restore_channel_monitor to ensure you have the latest monitor and re-enable normal
  71         /// channel operation.
  72         TemporaryFailure,
  73         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  74         /// different watchtower and cannot update with all watchtowers that were previously informed
  75         /// of this channel). This will force-close the channel in question.
  76         ///
  77         /// Should also be used to indicate a failure to update the local copy of the channel monitor.
  78         PermanentFailure,
  79 }
  80
  81 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
  82 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::insert_combine this
  83 /// means you tried to merge two monitors for different channels or for a channel which was
  84 /// restored from a backup and then generated new commitment updates.
  85 /// Contains a human-readable error message.
  86 #[derive(Debug)]
  87 pub struct MonitorUpdateError(pub &'static str);
  88
  89 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
  90 /// forward channel and from which info are needed to update HTLC in a backward channel.
  91 pub struct HTLCUpdate {
  92         pub(super) payment_hash: PaymentHash,
  93         pub(super) payment_preimage: Option<PaymentPreimage>,
  94         pub(super) source: HTLCSource
  95 }
  96
  97 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  98 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  99 /// events to it, while also taking any add_update_monitor events and passing them to some remote
 100 /// server(s).
 101 ///
 102 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
 103 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
 104 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
 105 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
 106 pub trait ManyChannelMonitor: Send + Sync {
 107         /// Adds or updates a monitor for the given `funding_txo`.
 108         ///
 109         /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
 110         /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
 111         /// any spends of it.
 112         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
 113
 114         /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
 115         /// with success or failure backward
 116         fn fetch_pending_htlc_updated(&self) -> Vec<HTLCUpdate>;
 117 }
 118
 119 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
 120 /// watchtower or watch our own channels.
 121 ///
 122 /// Note that you must provide your own key by which to refer to channels.
 123 ///
 124 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
 125 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
 126 /// index by a PublicKey which is required to sign any updates.
 127 ///
 128 /// If you're using this for local monitoring of your own channels, you probably want to use
 129 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
 130 pub struct SimpleManyChannelMonitor<Key> {
 131         #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
 132         pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 133         #[cfg(not(test))]
 134         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 135         chain_monitor: Arc<ChainWatchInterface>,
 136         broadcaster: Arc<BroadcasterInterface>,
 137         pending_events: Mutex<Vec<events::Event>>,
 138         pending_htlc_updated: Mutex<HashMap<PaymentHash, Vec<(HTLCSource, Option<PaymentPreimage>)>>>,
 139         logger: Arc<Logger>,
 140 }
 141
 142 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
 143         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
 144                 let block_hash = header.bitcoin_hash();
 145                 let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
 146                 let mut htlc_updated_infos = Vec::new();
 147                 {
 148                         let mut monitors = self.monitors.lock().unwrap();
 149                         for monitor in monitors.values_mut() {
 150                                 let (txn_outputs, spendable_outputs, mut htlc_updated) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
 151                                 if spendable_outputs.len() > 0 {
 152                                         new_events.push(events::Event::SpendableOutputs {
 153                                                 outputs: spendable_outputs,
 154                                         });
 155                                 }
 156
 157                                 for (ref txid, ref outputs) in txn_outputs {
 158                                         for (idx, output) in outputs.iter().enumerate() {
 159                                                 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
 160                                         }
 161                                 }
 162                                 htlc_updated_infos.append(&mut htlc_updated);
 163                         }
 164                 }
 165                 {
 166                         // ChannelManager will just need to fetch pending_htlc_updated and pass state backward
 167                         let mut pending_htlc_updated = self.pending_htlc_updated.lock().unwrap();
 168                         for htlc in htlc_updated_infos.drain(..) {
 169                                 match pending_htlc_updated.entry(htlc.2) {
 170                                         hash_map::Entry::Occupied(mut e) => {
 171                                                 // In case of reorg we may have htlc outputs solved in a different way so
 172                                                 // we prefer to keep claims but don't store duplicate updates for a given
 173                                                 // (payment_hash, HTLCSource) pair.
 174                                                 // TODO: Note that we currently don't really use this as ChannelManager
 175                                                 // will fail/claim backwards after the first block. We really should delay
 176                                                 // a few blocks before failing backwards (but can claim backwards
 177                                                 // immediately) as long as we have a few blocks of headroom.
 178                                                 let mut existing_claim = false;
 179                                                 e.get_mut().retain(|htlc_data| {
 180                                                         if htlc.0 == htlc_data.0 {
 181                                                                 if htlc_data.1.is_some() {
 182                                                                         existing_claim = true;
 183                                                                         true
 184                                                                 } else { false }
 185                                                         } else { true }
 186                                                 });
 187                                                 if !existing_claim {
 188                                                         e.get_mut().push((htlc.0, htlc.1));
 189                                                 }
 190                                         }
 191                                         hash_map::Entry::Vacant(e) => {
 192                                                 e.insert(vec![(htlc.0, htlc.1)]);
 193                                         }
 194                                 }
 195                         }
 196                 }
 197                 let mut pending_events = self.pending_events.lock().unwrap();
 198                 pending_events.append(&mut new_events);
 199         }
 200
 201         fn block_disconnected(&self, _: &BlockHeader) { }
 202 }
 203
 204 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
 205         /// Creates a new object which can be used to monitor several channels given the chain
 206         /// interface with which to register to receive notifications.
 207         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>) -> Arc<SimpleManyChannelMonitor<Key>> {
 208                 let res = Arc::new(SimpleManyChannelMonitor {
 209                         monitors: Mutex::new(HashMap::new()),
 210                         chain_monitor,
 211                         broadcaster,
 212                         pending_events: Mutex::new(Vec::new()),
 213                         pending_htlc_updated: Mutex::new(HashMap::new()),
 214                         logger,
 215                 });
 216                 let weak_res = Arc::downgrade(&res);
 217                 res.chain_monitor.register_listener(weak_res);
 218                 res
 219         }
 220
 221         /// Adds or udpates the monitor which monitors the channel referred to by the given key.
 222         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 223                 let mut monitors = self.monitors.lock().unwrap();
 224                 match monitors.get_mut(&key) {
 225                         Some(orig_monitor) => {
 226                                 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_info!(monitor.key_storage));
 227                                 return orig_monitor.insert_combine(monitor);
 228                         },
 229                         None => {}
 230                 };
 231                 match monitor.key_storage {
 232                         Storage::Local { ref funding_info, .. } => {
 233                                 match funding_info {
 234                                         &None => {
 235                                                 return Err(MonitorUpdateError("Try to update a useless monitor without funding_txo !"));
 236                                         },
 237                                         &Some((ref outpoint, ref script)) => {
 238                                                 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
 239                                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 240                                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 241                                         },
 242                                 }
 243                         },
 244                         Storage::Watchtower { .. } => {
 245                                 self.chain_monitor.watch_all_txn();
 246                         }
 247                 }
 248                 monitors.insert(key, monitor);
 249                 Ok(())
 250         }
 251 }
 252
 253 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 254         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 255                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 256                         Ok(_) => Ok(()),
 257                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 258                 }
 259         }
 260
 261         fn fetch_pending_htlc_updated(&self) -> Vec<HTLCUpdate> {
 262                 let mut updated = self.pending_htlc_updated.lock().unwrap();
 263                 let mut pending_htlcs_updated = Vec::with_capacity(updated.len());
 264                 for (k, v) in updated.drain() {
 265                         for htlc_data in v {
 266                                 pending_htlcs_updated.push(HTLCUpdate {
 267                                         payment_hash: k,
 268                                         payment_preimage: htlc_data.1,
 269                                         source: htlc_data.0,
 270                                 });
 271                         }
 272                 }
 273                 pending_htlcs_updated
 274         }
 275 }
 276
 277 impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
 278         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 279                 let mut pending_events = self.pending_events.lock().unwrap();
 280                 let mut ret = Vec::new();
 281                 mem::swap(&mut ret, &mut *pending_events);
 282                 ret
 283         }
 284 }
 285
 286 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 287 /// instead claiming it in its own individual transaction.
 288 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 289 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 290 /// HTLC-Success transaction.
 291 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
 292 /// transaction confirmed (and we use it in a few more, equivalent, places).
 293 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
 294 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
 295 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
 296 /// copies of ChannelMonitors, including watchtowers).
 297 pub(crate) const HTLC_FAIL_TIMEOUT_BLOCKS: u32 = 3;
 298
 299 #[derive(Clone, PartialEq)]
 300 enum Storage {
 301         Local {
 302                 revocation_base_key: SecretKey,
 303                 htlc_base_key: SecretKey,
 304                 delayed_payment_base_key: SecretKey,
 305                 payment_base_key: SecretKey,
 306                 shutdown_pubkey: PublicKey,
 307                 prev_latest_per_commitment_point: Option<PublicKey>,
 308                 latest_per_commitment_point: Option<PublicKey>,
 309                 funding_info: Option<(OutPoint, Script)>,
 310                 current_remote_commitment_txid: Option<Sha256dHash>,
 311                 prev_remote_commitment_txid: Option<Sha256dHash>,
 312         },
 313         Watchtower {
 314                 revocation_base_key: PublicKey,
 315                 htlc_base_key: PublicKey,
 316         }
 317 }
 318
 319 #[derive(Clone, PartialEq)]
 320 struct LocalSignedTx {
 321         /// txid of the transaction in tx, just used to make comparison faster
 322         txid: Sha256dHash,
 323         tx: Transaction,
 324         revocation_key: PublicKey,
 325         a_htlc_key: PublicKey,
 326         b_htlc_key: PublicKey,
 327         delayed_payment_key: PublicKey,
 328         feerate_per_kw: u64,
 329         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 330         htlc_sources: Vec<(PaymentHash, HTLCSource, Option<u32>)>,
 331 }
 332
 333 const SERIALIZATION_VERSION: u8 = 1;
 334 const MIN_SERIALIZATION_VERSION: u8 = 1;
 335
 336 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 337 /// on-chain transactions to ensure no loss of funds occurs.
 338 ///
 339 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 340 /// information and are actively monitoring the chain.
 341 #[derive(Clone)]
 342 pub struct ChannelMonitor {
 343         commitment_transaction_number_obscure_factor: u64,
 344
 345         key_storage: Storage,
 346         their_htlc_base_key: Option<PublicKey>,
 347         their_delayed_payment_base_key: Option<PublicKey>,
 348         // first is the idx of the first of the two revocation points
 349         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 350
 351         our_to_self_delay: u16,
 352         their_to_self_delay: Option<u16>,
 353
 354         old_secrets: [([u8; 32], u64); 49],
 355         remote_claimable_outpoints: HashMap<Sha256dHash, (Vec<HTLCOutputInCommitment>, Vec<(PaymentHash, HTLCSource, Option<u32>)>)>,
 356         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 357         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 358         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 359         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 360         /// can be used to derive the revocation key and claim the transactions.
 361         remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
 362         /// Cache used to make pruning of payment_preimages faster.
 363         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 364         /// remote transactions (ie should remain pretty small).
 365         /// Serialized to disk but should generally not be sent to Watchtowers.
 366         remote_hash_commitment_number: HashMap<PaymentHash, u64>,
 367
 368         // We store two local commitment transactions to avoid any race conditions where we may update
 369         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 370         // various monitors for one channel being out of sync, and us broadcasting a local
 371         // transaction for which we have deleted claim information on some watchtowers.
 372         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 373         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 374
 375         // Used just for ChannelManager to make sure it has the latest channel data during
 376         // deserialization
 377         current_remote_commitment_number: u64,
 378
 379         payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
 380
 381         destination_script: Script,
 382
 383         // We simply modify last_block_hash in Channel's block_connected so that serialization is
 384         // consistent but hopefully the users' copy handles block_connected in a consistent way.
 385         // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
 386         // their last_block_hash from its state and not based on updated copies that didn't run through
 387         // the full block_connected).
 388         pub(crate) last_block_hash: Sha256dHash,
 389         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 390         logger: Arc<Logger>,
 391 }
 392
 393 #[cfg(any(test, feature = "fuzztarget"))]
 394 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 395 /// underlying object
 396 impl PartialEq for ChannelMonitor {
 397         fn eq(&self, other: &Self) -> bool {
 398                 if self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 399                         self.key_storage != other.key_storage ||
 400                         self.their_htlc_base_key != other.their_htlc_base_key ||
 401                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 402                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 403                         self.our_to_self_delay != other.our_to_self_delay ||
 404                         self.their_to_self_delay != other.their_to_self_delay ||
 405                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 406                         self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
 407                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 408                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 409                         self.current_remote_commitment_number != other.current_remote_commitment_number ||
 410                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 411                         self.payment_preimages != other.payment_preimages ||
 412                         self.destination_script != other.destination_script
 413                 {
 414                         false
 415                 } else {
 416                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 417                                 if secret != o_secret || idx != o_idx {
 418                                         return false
 419                                 }
 420                         }
 421                         true
 422                 }
 423         }
 424 }
 425
 426 impl ChannelMonitor {
 427         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 {
 428                 ChannelMonitor {
 429                         commitment_transaction_number_obscure_factor: 0,
 430
 431                         key_storage: Storage::Local {
 432                                 revocation_base_key: revocation_base_key.clone(),
 433                                 htlc_base_key: htlc_base_key.clone(),
 434                                 delayed_payment_base_key: delayed_payment_base_key.clone(),
 435                                 payment_base_key: payment_base_key.clone(),
 436                                 shutdown_pubkey: shutdown_pubkey.clone(),
 437                                 prev_latest_per_commitment_point: None,
 438                                 latest_per_commitment_point: None,
 439                                 funding_info: None,
 440                                 current_remote_commitment_txid: None,
 441                                 prev_remote_commitment_txid: None,
 442                         },
 443                         their_htlc_base_key: None,
 444                         their_delayed_payment_base_key: None,
 445                         their_cur_revocation_points: None,
 446
 447                         our_to_self_delay: our_to_self_delay,
 448                         their_to_self_delay: None,
 449
 450                         old_secrets: [([0; 32], 1 << 48); 49],
 451                         remote_claimable_outpoints: HashMap::new(),
 452                         remote_commitment_txn_on_chain: HashMap::new(),
 453                         remote_hash_commitment_number: HashMap::new(),
 454
 455                         prev_local_signed_commitment_tx: None,
 456                         current_local_signed_commitment_tx: None,
 457                         current_remote_commitment_number: 1 << 48,
 458
 459                         payment_preimages: HashMap::new(),
 460                         destination_script: destination_script,
 461
 462                         last_block_hash: Default::default(),
 463                         secp_ctx: Secp256k1::new(),
 464                         logger,
 465                 }
 466         }
 467
 468         #[inline]
 469         fn place_secret(idx: u64) -> u8 {
 470                 for i in 0..48 {
 471                         if idx & (1 << i) == (1 << i) {
 472                                 return i
 473                         }
 474                 }
 475                 48
 476         }
 477
 478         #[inline]
 479         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 480                 let mut res: [u8; 32] = secret;
 481                 for i in 0..bits {
 482                         let bitpos = bits - 1 - i;
 483                         if idx & (1 << bitpos) == (1 << bitpos) {
 484                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 485                                 let mut sha = Sha256::new();
 486                                 sha.input(&res);
 487                                 sha.result(&mut res);
 488                         }
 489                 }
 490                 res
 491         }
 492
 493         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
 494         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 495         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 496         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
 497                 let pos = ChannelMonitor::place_secret(idx);
 498                 for i in 0..pos {
 499                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 500                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 501                                 return Err(MonitorUpdateError("Previous secret did not match new one"));
 502                         }
 503                 }
 504                 if self.get_min_seen_secret() <= idx {
 505                         return Ok(());
 506                 }
 507                 self.old_secrets[pos as usize] = (secret, idx);
 508
 509                 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
 510                 // events for now-revoked/fulfilled HTLCs.
 511                 // TODO: We should probably consider whether we're really getting the next secret here.
 512                 if let Storage::Local { ref mut prev_remote_commitment_txid, .. } = self.key_storage {
 513                         if let Some(txid) = prev_remote_commitment_txid.take() {
 514                                 self.remote_claimable_outpoints.get_mut(&txid).unwrap().1 = Vec::new();
 515                         }
 516                 }
 517
 518                 if !self.payment_preimages.is_empty() {
 519                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 520                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 521                         let min_idx = self.get_min_seen_secret();
 522                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 523
 524                         self.payment_preimages.retain(|&k, _| {
 525                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 526                                         if k == htlc.payment_hash {
 527                                                 return true
 528                                         }
 529                                 }
 530                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 531                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 532                                                 if k == htlc.payment_hash {
 533                                                         return true
 534                                                 }
 535                                         }
 536                                 }
 537                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 538                                         if *cn < min_idx {
 539                                                 return true
 540                                         }
 541                                         true
 542                                 } else { false };
 543                                 if contains {
 544                                         remote_hash_commitment_number.remove(&k);
 545                                 }
 546                                 false
 547                         });
 548                 }
 549
 550                 Ok(())
 551         }
 552
 553         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 554         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 555         /// possibly future revocation/preimage information) to claim outputs where possible.
 556         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 557         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, htlc_sources: Vec<(PaymentHash, HTLCSource, Option<u32>)>, commitment_number: u64, their_revocation_point: PublicKey) {
 558                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 559                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 560                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 561                 // timeouts)
 562                 for ref htlc in &htlc_outputs {
 563                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 564                 }
 565
 566                 let new_txid = unsigned_commitment_tx.txid();
 567                 if let Storage::Local { ref mut current_remote_commitment_txid, ref mut prev_remote_commitment_txid, .. } = self.key_storage {
 568                         *prev_remote_commitment_txid = current_remote_commitment_txid.take();
 569                         *current_remote_commitment_txid = Some(new_txid);
 570                 }
 571                 self.remote_claimable_outpoints.insert(new_txid, (htlc_outputs, htlc_sources));
 572                 self.current_remote_commitment_number = commitment_number;
 573                 //TODO: Merge this into the other per-remote-transaction output storage stuff
 574                 match self.their_cur_revocation_points {
 575                         Some(old_points) => {
 576                                 if old_points.0 == commitment_number + 1 {
 577                                         self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
 578                                 } else if old_points.0 == commitment_number + 2 {
 579                                         if let Some(old_second_point) = old_points.2 {
 580                                                 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
 581                                         } else {
 582                                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 583                                         }
 584                                 } else {
 585                                         self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 586                                 }
 587                         },
 588                         None => {
 589                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 590                         }
 591                 }
 592         }
 593
 594         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 595         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 596         /// is important that any clones of this channel monitor (including remote clones) by kept
 597         /// up-to-date as our local commitment transaction is updated.
 598         /// Panics if set_their_to_self_delay has never been called.
 599         /// Also update Storage with latest local per_commitment_point to derive local_delayedkey in
 600         /// case of onchain HTLC tx
 601         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)>, htlc_sources: Vec<(PaymentHash, HTLCSource, Option<u32>)>) {
 602                 assert!(self.their_to_self_delay.is_some());
 603                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 604                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 605                         txid: signed_commitment_tx.txid(),
 606                         tx: signed_commitment_tx,
 607                         revocation_key: local_keys.revocation_key,
 608                         a_htlc_key: local_keys.a_htlc_key,
 609                         b_htlc_key: local_keys.b_htlc_key,
 610                         delayed_payment_key: local_keys.a_delayed_payment_key,
 611                         feerate_per_kw,
 612                         htlc_outputs,
 613                         htlc_sources,
 614                 });
 615
 616                 if let Storage::Local { ref mut latest_per_commitment_point, .. } = self.key_storage {
 617                         *latest_per_commitment_point = Some(local_keys.per_commitment_point);
 618                 } else {
 619                         panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 620                 }
 621         }
 622
 623         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 624         /// commitment_tx_infos which contain the payment hash have been revoked.
 625         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
 626                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 627         }
 628
 629         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 630         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 631         /// chain for new blocks/transactions.
 632         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 633                 match self.key_storage {
 634                         Storage::Local { ref funding_info, .. } => {
 635                                 if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 636                                 let our_funding_info = funding_info;
 637                                 if let Storage::Local { ref funding_info, .. } = other.key_storage {
 638                                         if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 639                                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 640                                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 641                                         if funding_info.as_ref().unwrap().0 != our_funding_info.as_ref().unwrap().0 {
 642                                                 return Err(MonitorUpdateError("Funding transaction outputs are not identical!"));
 643                                         }
 644                                 } else {
 645                                         return Err(MonitorUpdateError("Try to combine a Local monitor with a Watchtower one !"));
 646                                 }
 647                         },
 648                         Storage::Watchtower { .. } => {
 649                                 if let Storage::Watchtower { .. } = other.key_storage {
 650                                         unimplemented!();
 651                                 } else {
 652                                         return Err(MonitorUpdateError("Try to combine a Watchtower monitor with a Local one !"));
 653                                 }
 654                         },
 655                 }
 656                 let other_min_secret = other.get_min_seen_secret();
 657                 let our_min_secret = self.get_min_seen_secret();
 658                 if our_min_secret > other_min_secret {
 659                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
 660                 }
 661                 if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
 662                         if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
 663                                 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);
 664                                 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);
 665                                 if our_commitment_number >= other_commitment_number {
 666                                         self.key_storage = other.key_storage;
 667                                 }
 668                         }
 669                 }
 670                 // TODO: We should use current_remote_commitment_number and the commitment number out of
 671                 // local transactions to decide how to merge
 672                 if our_min_secret >= other_min_secret {
 673                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 674                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 675                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 676                         }
 677                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 678                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 679                         }
 680                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 681                                 self.current_local_signed_commitment_tx = Some(local_tx);
 682                         }
 683                         self.payment_preimages = other.payment_preimages;
 684                 }
 685
 686                 self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
 687                 Ok(())
 688         }
 689
 690         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 691         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 692                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 693                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 694         }
 695
 696         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 697         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 698         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 699         /// provides slightly better privacy.
 700         /// It's the responsibility of the caller to register outpoint and script with passing the former
 701         /// value as key to add_update_monitor.
 702         pub(super) fn set_funding_info(&mut self, new_funding_info: (OutPoint, Script)) {
 703                 match self.key_storage {
 704                         Storage::Local { ref mut funding_info, .. } => {
 705                                 *funding_info = Some(new_funding_info);
 706                         },
 707                         Storage::Watchtower { .. } => {
 708                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 709                         }
 710                 }
 711         }
 712
 713         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 714         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 715                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 716                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 717         }
 718
 719         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 720                 self.their_to_self_delay = Some(their_to_self_delay);
 721         }
 722
 723         pub(super) fn unset_funding_info(&mut self) {
 724                 match self.key_storage {
 725                         Storage::Local { ref mut funding_info, .. } => {
 726                                 *funding_info = None;
 727                         },
 728                         Storage::Watchtower { .. } => {
 729                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 730                         },
 731                 }
 732         }
 733
 734         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 735         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 736                 match self.key_storage {
 737                         Storage::Local { ref funding_info, .. } => {
 738                                 match funding_info {
 739                                         &Some((outpoint, _)) => Some(outpoint),
 740                                         &None => None
 741                                 }
 742                         },
 743                         Storage::Watchtower { .. } => {
 744                                 return None;
 745                         }
 746                 }
 747         }
 748
 749         /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
 750         /// Generally useful when deserializing as during normal operation the return values of
 751         /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
 752         /// that the get_funding_txo outpoint and transaction must also be monitored for!).
 753         pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
 754                 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
 755                 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
 756                         for (idx, output) in outputs.iter().enumerate() {
 757                                 res.push(((*txid).clone(), idx as u32, output));
 758                         }
 759                 }
 760                 res
 761         }
 762
 763         /// Serializes into a vec, with various modes for the exposed pub fns
 764         fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
 765                 //TODO: We still write out all the serialization here manually instead of using the fancy
 766                 //serialization framework we have, we should migrate things over to it.
 767                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 768                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 769
 770                 // Set in initial Channel-object creation, so should always be set by now:
 771                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
 772
 773                 match self.key_storage {
 774                         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, current_remote_commitment_txid, prev_remote_commitment_txid } => {
 775                                 writer.write_all(&[0; 1])?;
 776                                 writer.write_all(&revocation_base_key[..])?;
 777                                 writer.write_all(&htlc_base_key[..])?;
 778                                 writer.write_all(&delayed_payment_base_key[..])?;
 779                                 writer.write_all(&payment_base_key[..])?;
 780                                 writer.write_all(&shutdown_pubkey.serialize())?;
 781                                 if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point {
 782                                         writer.write_all(&[1; 1])?;
 783                                         writer.write_all(&prev_latest_per_commitment_point.serialize())?;
 784                                 } else {
 785                                         writer.write_all(&[0; 1])?;
 786                                 }
 787                                 if let Some(ref latest_per_commitment_point) = *latest_per_commitment_point {
 788                                         writer.write_all(&[1; 1])?;
 789                                         writer.write_all(&latest_per_commitment_point.serialize())?;
 790                                 } else {
 791                                         writer.write_all(&[0; 1])?;
 792                                 }
 793                                 match funding_info  {
 794                                         &Some((ref outpoint, ref script)) => {
 795                                                 writer.write_all(&outpoint.txid[..])?;
 796                                                 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
 797                                                 script.write(writer)?;
 798                                         },
 799                                         &None => {
 800                                                 debug_assert!(false, "Try to serialize a useless Local monitor !");
 801                                         },
 802                                 }
 803                                 if let Some(ref txid) = current_remote_commitment_txid {
 804                                         writer.write_all(&[1; 1])?;
 805                                         writer.write_all(&txid[..])?;
 806                                 } else {
 807                                         writer.write_all(&[0; 1])?;
 808                                 }
 809                                 if let Some(ref txid) = prev_remote_commitment_txid {
 810                                         writer.write_all(&[1; 1])?;
 811                                         writer.write_all(&txid[..])?;
 812                                 } else {
 813                                         writer.write_all(&[0; 1])?;
 814                                 }
 815                         },
 816                         Storage::Watchtower { .. } => unimplemented!(),
 817                 }
 818
 819                 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
 820                 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
 821
 822                 match self.their_cur_revocation_points {
 823                         Some((idx, pubkey, second_option)) => {
 824                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
 825                                 writer.write_all(&pubkey.serialize())?;
 826                                 match second_option {
 827                                         Some(second_pubkey) => {
 828                                                 writer.write_all(&second_pubkey.serialize())?;
 829                                         },
 830                                         None => {
 831                                                 writer.write_all(&[0; 33])?;
 832                                         },
 833                                 }
 834                         },
 835                         None => {
 836                                 writer.write_all(&byte_utils::be48_to_array(0))?;
 837                         },
 838                 }
 839
 840                 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
 841                 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
 842
 843                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 844                         writer.write_all(secret)?;
 845                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 846                 }
 847
 848                 macro_rules! serialize_htlc_in_commitment {
 849                         ($htlc_output: expr) => {
 850                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
 851                                 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
 852                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
 853                                 writer.write_all(&$htlc_output.payment_hash.0[..])?;
 854                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.transaction_output_index))?;
 855                         }
 856                 }
 857
 858                 macro_rules! serialize_htlc_source {
 859                         ($htlc_source: expr) => {
 860                                 $htlc_source.0.write(writer)?;
 861                                 $htlc_source.1.write(writer)?;
 862                                 if let &Some(ref txo) = &$htlc_source.2 {
 863                                         writer.write_all(&[1; 1])?;
 864                                         txo.write(writer)?;
 865                                 } else {
 866                                         writer.write_all(&[0; 1])?;
 867                                 }
 868                         }
 869                 }
 870
 871
 872                 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
 873                 for (ref txid, &(ref htlc_infos, ref htlc_sources)) in self.remote_claimable_outpoints.iter() {
 874                         writer.write_all(&txid[..])?;
 875                         writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
 876                         for ref htlc_output in htlc_infos.iter() {
 877                                 serialize_htlc_in_commitment!(htlc_output);
 878                         }
 879                         writer.write_all(&byte_utils::be64_to_array(htlc_sources.len() as u64))?;
 880                         for ref htlc_source in htlc_sources.iter() {
 881                                 serialize_htlc_source!(htlc_source);
 882                         }
 883                 }
 884
 885                 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
 886                 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
 887                         writer.write_all(&txid[..])?;
 888                         writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
 889                         (txouts.len() as u64).write(writer)?;
 890                         for script in txouts.iter() {
 891                                 script.write(writer)?;
 892                         }
 893                 }
 894
 895                 if for_local_storage {
 896                         writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
 897                         for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 898                                 writer.write_all(&payment_hash.0[..])?;
 899                                 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
 900                         }
 901                 } else {
 902                         writer.write_all(&byte_utils::be64_to_array(0))?;
 903                 }
 904
 905                 macro_rules! serialize_local_tx {
 906                         ($local_tx: expr) => {
 907                                 if let Err(e) = $local_tx.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 908                                         match e {
 909                                                 encode::Error::Io(e) => return Err(e),
 910                                                 _ => panic!("local tx must have been well-formed!"),
 911                                         }
 912                                 }
 913
 914                                 writer.write_all(&$local_tx.revocation_key.serialize())?;
 915                                 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
 916                                 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
 917                                 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
 918
 919                                 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
 920                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
 921                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 922                                         serialize_htlc_in_commitment!(htlc_output);
 923                                         writer.write_all(&their_sig.serialize_compact(&self.secp_ctx))?;
 924                                         writer.write_all(&our_sig.serialize_compact(&self.secp_ctx))?;
 925                                 }
 926                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_sources.len() as u64))?;
 927                                 for ref htlc_source in $local_tx.htlc_sources.iter() {
 928                                         serialize_htlc_source!(htlc_source);
 929                                 }
 930                         }
 931                 }
 932
 933                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 934                         writer.write_all(&[1; 1])?;
 935                         serialize_local_tx!(prev_local_tx);
 936                 } else {
 937                         writer.write_all(&[0; 1])?;
 938                 }
 939
 940                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 941                         writer.write_all(&[1; 1])?;
 942                         serialize_local_tx!(cur_local_tx);
 943                 } else {
 944                         writer.write_all(&[0; 1])?;
 945                 }
 946
 947                 if for_local_storage {
 948                         writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
 949                 } else {
 950                         writer.write_all(&byte_utils::be48_to_array(0))?;
 951                 }
 952
 953                 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
 954                 for payment_preimage in self.payment_preimages.values() {
 955                         writer.write_all(&payment_preimage.0[..])?;
 956                 }
 957
 958                 self.last_block_hash.write(writer)?;
 959                 self.destination_script.write(writer)?;
 960
 961                 Ok(())
 962         }
 963
 964         /// Writes this monitor into the given writer, suitable for writing to disk.
 965         ///
 966         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 967         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 968         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 969         /// common block that appears on your best chain as well as on the chain which contains the
 970         /// last block hash returned) upon deserializing the object!
 971         pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 972                 self.write(writer, true)
 973         }
 974
 975         /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
 976         ///
 977         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 978         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 979         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 980         /// common block that appears on your best chain as well as on the chain which contains the
 981         /// last block hash returned) upon deserializing the object!
 982         pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 983                 self.write(writer, false)
 984         }
 985
 986         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 987         //we want to leave out (eg funding_txo, etc).
 988
 989         /// Can only fail if idx is < get_min_seen_secret
 990         pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
 991                 for i in 0..self.old_secrets.len() {
 992                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 993                                 return Some(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 994                         }
 995                 }
 996                 assert!(idx < self.get_min_seen_secret());
 997                 None
 998         }
 999
1000         pub(super) fn get_min_seen_secret(&self) -> u64 {
1001                 //TODO This can be optimized?
1002                 let mut min = 1 << 48;
1003                 for &(_, idx) in self.old_secrets.iter() {
1004                         if idx < min {
1005                                 min = idx;
1006                         }
1007                 }
1008                 min
1009         }
1010
1011         pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1012                 self.current_remote_commitment_number
1013         }
1014
1015         pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1016                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1017                         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)
1018                 } else { 0xffff_ffff_ffff }
1019         }
1020
1021         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1022         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1023         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1024         /// HTLC-Success/HTLC-Timeout transactions.
1025         /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1026         /// revoked remote commitment tx
1027         fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>, Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)>)  {
1028                 // Most secp and related errors trying to create keys means we have no hope of constructing
1029                 // a spend transaction...so we return no transactions to broadcast
1030                 let mut txn_to_broadcast = Vec::new();
1031                 let mut watch_outputs = Vec::new();
1032                 let mut spendable_outputs = Vec::new();
1033                 let mut htlc_updated = Vec::new();
1034
1035                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1036                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1037
1038                 macro_rules! ignore_error {
1039                         ( $thing : expr ) => {
1040                                 match $thing {
1041                                         Ok(a) => a,
1042                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated)
1043                                 }
1044                         };
1045                 }
1046
1047                 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);
1048                 if commitment_number >= self.get_min_seen_secret() {
1049                         let secret = self.get_secret(commitment_number).unwrap();
1050                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1051                         let (revocation_pubkey, b_htlc_key, local_payment_key) = match self.key_storage {
1052                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, ref payment_base_key, .. } => {
1053                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1054                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1055                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))),
1056                                         Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
1057                                 },
1058                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
1059                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1060                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
1061                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)),
1062                                         None)
1063                                 },
1064                         };
1065                         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()));
1066                         let a_htlc_key = match self.their_htlc_base_key {
1067                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated),
1068                                 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)),
1069                         };
1070
1071                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1072                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1073
1074                         let local_payment_p2wpkh = if let Some(payment_key) = local_payment_key {
1075                                 // Note that the Network here is ignored as we immediately drop the address for the
1076                                 // script_pubkey version.
1077                                 let payment_hash160 = Hash160::from_data(&PublicKey::from_secret_key(&self.secp_ctx, &payment_key).serialize());
1078                                 Some(Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script())
1079                         } else { None };
1080
1081                         let mut total_value = 0;
1082                         let mut values = Vec::new();
1083                         let mut inputs = Vec::new();
1084                         let mut htlc_idxs = Vec::new();
1085
1086                         for (idx, outp) in tx.output.iter().enumerate() {
1087                                 if outp.script_pubkey == revokeable_p2wsh {
1088                                         inputs.push(TxIn {
1089                                                 previous_output: BitcoinOutPoint {
1090                                                         txid: commitment_txid,
1091                                                         vout: idx as u32,
1092                                                 },
1093                                                 script_sig: Script::new(),
1094                                                 sequence: 0xfffffffd,
1095                                                 witness: Vec::new(),
1096                                         });
1097                                         htlc_idxs.push(None);
1098                                         values.push(outp.value);
1099                                         total_value += outp.value;
1100                                 } else if Some(&outp.script_pubkey) == local_payment_p2wpkh.as_ref() {
1101                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1102                                                 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1103                                                 key: local_payment_key.unwrap(),
1104                                                 output: outp.clone(),
1105                                         });
1106                                 }
1107                         }
1108
1109                         macro_rules! sign_input {
1110                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
1111                                         {
1112                                                 let (sig, redeemscript) = match self.key_storage {
1113                                                         Storage::Local { ref revocation_base_key, .. } => {
1114                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
1115                                                                         let htlc = &per_commitment_option.unwrap().0[$htlc_idx.unwrap()];
1116                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
1117                                                                 };
1118                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1119                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1120                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
1121                                                         },
1122                                                         Storage::Watchtower { .. } => {
1123                                                                 unimplemented!();
1124                                                         }
1125                                                 };
1126                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1127                                                 $input.witness[0].push(SigHashType::All as u8);
1128                                                 if $htlc_idx.is_none() {
1129                                                         $input.witness.push(vec!(1));
1130                                                 } else {
1131                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
1132                                                 }
1133                                                 $input.witness.push(redeemscript.into_bytes());
1134                                         }
1135                                 }
1136                         }
1137
1138                         if let Some(&(ref per_commitment_data, _)) = per_commitment_option {
1139                                 inputs.reserve_exact(per_commitment_data.len());
1140
1141                                 for (idx, ref htlc) in per_commitment_data.iter().enumerate() {
1142                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1143                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
1144                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1145                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1146                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); // Corrupted per_commitment_data, fuck this user
1147                                         }
1148                                         let input = TxIn {
1149                                                 previous_output: BitcoinOutPoint {
1150                                                         txid: commitment_txid,
1151                                                         vout: htlc.transaction_output_index,
1152                                                 },
1153                                                 script_sig: Script::new(),
1154                                                 sequence: 0xfffffffd,
1155                                                 witness: Vec::new(),
1156                                         };
1157                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1158                                                 inputs.push(input);
1159                                                 htlc_idxs.push(Some(idx));
1160                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1161                                                 total_value += htlc.amount_msat / 1000;
1162                                         } else {
1163                                                 let mut single_htlc_tx = Transaction {
1164                                                         version: 2,
1165                                                         lock_time: 0,
1166                                                         input: vec![input],
1167                                                         output: vec!(TxOut {
1168                                                                 script_pubkey: self.destination_script.clone(),
1169                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1170                                                         }),
1171                                                 };
1172                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1173                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1174                                                 txn_to_broadcast.push(single_htlc_tx);
1175                                         }
1176                                 }
1177                         }
1178
1179                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1180                                 // We're definitely a remote commitment transaction!
1181                                 log_trace!(self, "Got broadcast of revoked remote commitment transaction, generating general spend tx with {} inputs and {} other txn to broadcast", inputs.len(), txn_to_broadcast.len());
1182                                 watch_outputs.append(&mut tx.output.clone());
1183                                 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1184                         }
1185                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); } // Nothing to be done...probably a false positive/local tx
1186
1187                         let outputs = vec!(TxOut {
1188                                 script_pubkey: self.destination_script.clone(),
1189                                 value: total_value, //TODO: - fee
1190                         });
1191                         let mut spend_tx = Transaction {
1192                                 version: 2,
1193                                 lock_time: 0,
1194                                 input: inputs,
1195                                 output: outputs,
1196                         };
1197
1198                         let mut values_drain = values.drain(..);
1199                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1200
1201                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1202                                 let value = values_drain.next().unwrap();
1203                                 sign_input!(sighash_parts, input, htlc_idx, value);
1204                         }
1205
1206                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1207                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1208                                 output: spend_tx.output[0].clone(),
1209                         });
1210                         txn_to_broadcast.push(spend_tx);
1211
1212                         // TODO: We really should only fail backwards after our revocation claims have been
1213                         // confirmed, but we also need to do more other tracking of in-flight pre-confirm
1214                         // on-chain claims, so we can do that at the same time.
1215                         if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
1216                                 if let &Some(ref txid) = current_remote_commitment_txid {
1217                                         if let Some(&(_, ref latest_outpoints)) = self.remote_claimable_outpoints.get(&txid) {
1218                                                 for &(ref payment_hash, ref source, _) in latest_outpoints.iter() {
1219                                                         log_trace!(self, "Failing HTLC with payment_hash {} from current remote commitment tx due to broadcast of revoked remote commitment transaction", log_bytes!(payment_hash.0));
1220                                                         htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
1221                                                 }
1222                                         }
1223                                 }
1224                                 if let &Some(ref txid) = prev_remote_commitment_txid {
1225                                         if let Some(&(_, ref prev_outpoint)) = self.remote_claimable_outpoints.get(&txid) {
1226                                                 for &(ref payment_hash, ref source, _) in prev_outpoint.iter() {
1227                                                         log_trace!(self, "Failing HTLC with payment_hash {} from previous remote commitment tx due to broadcast of revoked remote commitment transaction", log_bytes!(payment_hash.0));
1228                                                         htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
1229                                                 }
1230                                         }
1231                                 }
1232                         }
1233                         // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1234                 } else if let Some(per_commitment_data) = per_commitment_option {
1235                         // While this isn't useful yet, there is a potential race where if a counterparty
1236                         // revokes a state at the same time as the commitment transaction for that state is
1237                         // confirmed, and the watchtower receives the block before the user, the user could
1238                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1239                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1240                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1241                         // insert it here.
1242                         watch_outputs.append(&mut tx.output.clone());
1243                         self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1244
1245                         if let Some(revocation_points) = self.their_cur_revocation_points {
1246                                 let revocation_point_option =
1247                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1248                                         else if let Some(point) = revocation_points.2.as_ref() {
1249                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1250                                         } else { None };
1251                                 if let Some(revocation_point) = revocation_point_option {
1252                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1253                                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, .. } => {
1254                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1255                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1256                                                 },
1257                                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
1258                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1259                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1260                                                 },
1261                                         };
1262                                         let a_htlc_key = match self.their_htlc_base_key {
1263                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated),
1264                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1265                                         };
1266
1267                                         for (idx, outp) in tx.output.iter().enumerate() {
1268                                                 if outp.script_pubkey.is_v0_p2wpkh() {
1269                                                         match self.key_storage {
1270                                                                 Storage::Local { ref payment_base_key, .. } => {
1271                                                                         if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &revocation_point, &payment_base_key) {
1272                                                                                 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1273                                                                                         outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1274                                                                                         key: local_key,
1275                                                                                         output: outp.clone(),
1276                                                                                 });
1277                                                                         }
1278                                                                 },
1279                                                                 Storage::Watchtower { .. } => {}
1280                                                         }
1281                                                         break; // Only to_remote ouput is claimable
1282                                                 }
1283                                         }
1284
1285                                         let mut total_value = 0;
1286                                         let mut values = Vec::new();
1287                                         let mut inputs = Vec::new();
1288
1289                                         macro_rules! sign_input {
1290                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1291                                                         {
1292                                                                 let (sig, redeemscript) = match self.key_storage {
1293                                                                         Storage::Local { ref htlc_base_key, .. } => {
1294                                                                                 let htlc = &per_commitment_option.unwrap().0[$input.sequence as usize];
1295                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1296                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1297                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1298                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1299                                                                         },
1300                                                                         Storage::Watchtower { .. } => {
1301                                                                                 unimplemented!();
1302                                                                         }
1303                                                                 };
1304                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1305                                                                 $input.witness[0].push(SigHashType::All as u8);
1306                                                                 $input.witness.push($preimage);
1307                                                                 $input.witness.push(redeemscript.into_bytes());
1308                                                         }
1309                                                 }
1310                                         }
1311
1312                                         for (idx, ref htlc) in per_commitment_data.0.iter().enumerate() {
1313                                                 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1314                                                 if htlc.transaction_output_index as usize >= tx.output.len() ||
1315                                                                 tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1316                                                                 tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1317                                                         return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); // Corrupted per_commitment_data, fuck this user
1318                                                 }
1319                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1320                                                         let input = TxIn {
1321                                                                 previous_output: BitcoinOutPoint {
1322                                                                         txid: commitment_txid,
1323                                                                         vout: htlc.transaction_output_index,
1324                                                                 },
1325                                                                 script_sig: Script::new(),
1326                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1327                                                                 witness: Vec::new(),
1328                                                         };
1329                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1330                                                                 inputs.push(input);
1331                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1332                                                                 total_value += htlc.amount_msat / 1000;
1333                                                         } else {
1334                                                                 let mut single_htlc_tx = Transaction {
1335                                                                         version: 2,
1336                                                                         lock_time: 0,
1337                                                                         input: vec![input],
1338                                                                         output: vec!(TxOut {
1339                                                                                 script_pubkey: self.destination_script.clone(),
1340                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1341                                                                         }),
1342                                                                 };
1343                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1344                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.0.to_vec());
1345                                                                 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1346                                                                         outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
1347                                                                         output: single_htlc_tx.output[0].clone(),
1348                                                                 });
1349                                                                 txn_to_broadcast.push(single_htlc_tx);
1350                                                         }
1351                                                 }
1352                                                 if !htlc.offered {
1353                                                         // TODO: If the HTLC has already expired, potentially merge it with the
1354                                                         // rest of the claim transaction, as above.
1355                                                         let input = TxIn {
1356                                                                 previous_output: BitcoinOutPoint {
1357                                                                         txid: commitment_txid,
1358                                                                         vout: htlc.transaction_output_index,
1359                                                                 },
1360                                                                 script_sig: Script::new(),
1361                                                                 sequence: idx as u32,
1362                                                                 witness: Vec::new(),
1363                                                         };
1364                                                         let mut timeout_tx = Transaction {
1365                                                                 version: 2,
1366                                                                 lock_time: htlc.cltv_expiry,
1367                                                                 input: vec![input],
1368                                                                 output: vec!(TxOut {
1369                                                                         script_pubkey: self.destination_script.clone(),
1370                                                                         value: htlc.amount_msat / 1000,
1371                                                                 }),
1372                                                         };
1373                                                         let sighash_parts = bip143::SighashComponents::new(&timeout_tx);
1374                                                         sign_input!(sighash_parts, timeout_tx.input[0], htlc.amount_msat / 1000, vec![0]);
1375                                                         txn_to_broadcast.push(timeout_tx);
1376                                                 }
1377                                         }
1378
1379                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); } // Nothing to be done...probably a false positive/local tx
1380
1381                                         let outputs = vec!(TxOut {
1382                                                 script_pubkey: self.destination_script.clone(),
1383                                                 value: total_value, //TODO: - fee
1384                                         });
1385                                         let mut spend_tx = Transaction {
1386                                                 version: 2,
1387                                                 lock_time: 0,
1388                                                 input: inputs,
1389                                                 output: outputs,
1390                                         };
1391
1392                                         let mut values_drain = values.drain(..);
1393                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1394
1395                                         for input in spend_tx.input.iter_mut() {
1396                                                 let value = values_drain.next().unwrap();
1397                                                 sign_input!(sighash_parts, input, value.0, (value.1).0.to_vec());
1398                                         }
1399
1400                                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1401                                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1402                                                 output: spend_tx.output[0].clone(),
1403                                         });
1404                                         txn_to_broadcast.push(spend_tx);
1405                                 }
1406                         }
1407                 }
1408
1409                 (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated)
1410         }
1411
1412         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1413         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> (Option<Transaction>, Option<SpendableOutputDescriptor>) {
1414                 if tx.input.len() != 1 || tx.output.len() != 1 {
1415                         return (None, None)
1416                 }
1417
1418                 macro_rules! ignore_error {
1419                         ( $thing : expr ) => {
1420                                 match $thing {
1421                                         Ok(a) => a,
1422                                         Err(_) => return (None, None)
1423                                 }
1424                         };
1425                 }
1426
1427                 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (None, None); };
1428                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1429                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1430                 let revocation_pubkey = match self.key_storage {
1431                         Storage::Local { ref revocation_base_key, .. } => {
1432                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1433                         },
1434                         Storage::Watchtower { ref revocation_base_key, .. } => {
1435                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1436                         },
1437                 };
1438                 let delayed_key = match self.their_delayed_payment_base_key {
1439                         None => return (None, None),
1440                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1441                 };
1442                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1443                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1444                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1445
1446                 let mut inputs = Vec::new();
1447                 let mut amount = 0;
1448
1449                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1450                         inputs.push(TxIn {
1451                                 previous_output: BitcoinOutPoint {
1452                                         txid: htlc_txid,
1453                                         vout: 0,
1454                                 },
1455                                 script_sig: Script::new(),
1456                                 sequence: 0xfffffffd,
1457                                 witness: Vec::new(),
1458                         });
1459                         amount = tx.output[0].value;
1460                 }
1461
1462                 if !inputs.is_empty() {
1463                         let outputs = vec!(TxOut {
1464                                 script_pubkey: self.destination_script.clone(),
1465                                 value: amount, //TODO: - fee
1466                         });
1467
1468                         let mut spend_tx = Transaction {
1469                                 version: 2,
1470                                 lock_time: 0,
1471                                 input: inputs,
1472                                 output: outputs,
1473                         };
1474
1475                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1476
1477                         let sig = match self.key_storage {
1478                                 Storage::Local { ref revocation_base_key, .. } => {
1479                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1480                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1481                                         self.secp_ctx.sign(&sighash, &revocation_key)
1482                                 }
1483                                 Storage::Watchtower { .. } => {
1484                                         unimplemented!();
1485                                 }
1486                         };
1487                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1488                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1489                         spend_tx.input[0].witness.push(vec!(1));
1490                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1491
1492                         let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
1493                         let output = spend_tx.output[0].clone();
1494                         (Some(spend_tx), Some(SpendableOutputDescriptor::StaticOutput { outpoint, output }))
1495                 } else { (None, None) }
1496         }
1497
1498         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, per_commitment_point: &Option<PublicKey>, delayed_payment_base_key: &Option<SecretKey>) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>, Vec<TxOut>) {
1499                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1500                 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1501                 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1502
1503                 macro_rules! add_dynamic_output {
1504                         ($father_tx: expr, $vout: expr) => {
1505                                 if let Some(ref per_commitment_point) = *per_commitment_point {
1506                                         if let Some(ref delayed_payment_base_key) = *delayed_payment_base_key {
1507                                                 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, per_commitment_point, delayed_payment_base_key) {
1508                                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WSH {
1509                                                                 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1510                                                                 key: local_delayedkey,
1511                                                                 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1512                                                                 to_self_delay: self.our_to_self_delay,
1513                                                                 output: $father_tx.output[$vout as usize].clone(),
1514                                                         });
1515                                                 }
1516                                         }
1517                                 }
1518                         }
1519                 }
1520
1521
1522                 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1523                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1524                 for (idx, output) in local_tx.tx.output.iter().enumerate() {
1525                         if output.script_pubkey == revokeable_p2wsh {
1526                                 add_dynamic_output!(local_tx.tx, idx as u32);
1527                                 break;
1528                         }
1529                 }
1530
1531                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1532                         if htlc.offered {
1533                                 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);
1534
1535                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1536
1537                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1538                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1539                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1540                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1541
1542                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1543                                 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());
1544
1545                                 add_dynamic_output!(htlc_timeout_tx, 0);
1546                                 res.push(htlc_timeout_tx);
1547                         } else {
1548                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1549                                         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);
1550
1551                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1552
1553                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1554                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1555                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1556                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1557
1558                                         htlc_success_tx.input[0].witness.push(payment_preimage.0.to_vec());
1559                                         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());
1560
1561                                         add_dynamic_output!(htlc_success_tx, 0);
1562                                         res.push(htlc_success_tx);
1563                                 }
1564                         }
1565                         watch_outputs.push(local_tx.tx.output[htlc.transaction_output_index as usize].clone());
1566                 }
1567
1568                 (res, spendable_outputs, watch_outputs)
1569         }
1570
1571         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1572         /// revoked using data in local_claimable_outpoints.
1573         /// Should not be used if check_spend_revoked_transaction succeeds.
1574         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>, (Sha256dHash, Vec<TxOut>)) {
1575                 let commitment_txid = tx.txid();
1576                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1577                         if local_tx.txid == commitment_txid {
1578                                 match self.key_storage {
1579                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1580                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1581                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1582                                         },
1583                                         Storage::Watchtower { .. } => {
1584                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, &None, &None);
1585                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1586                                         }
1587                                 }
1588                         }
1589                 }
1590                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1591                         if local_tx.txid == commitment_txid {
1592                                 match self.key_storage {
1593                                         Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1594                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key));
1595                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1596                                         },
1597                                         Storage::Watchtower { .. } => {
1598                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, &None, &None);
1599                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1600                                         }
1601                                 }
1602                         }
1603                 }
1604                 (Vec::new(), Vec::new(), (commitment_txid, Vec::new()))
1605         }
1606
1607         /// Generate a spendable output event when closing_transaction get registered onchain.
1608         fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option<SpendableOutputDescriptor> {
1609                 if tx.input[0].sequence == 0xFFFFFFFF && !tx.input[0].witness.is_empty() && tx.input[0].witness.last().unwrap().len() == 71 {
1610                         match self.key_storage {
1611                                 Storage::Local { ref shutdown_pubkey, .. } =>  {
1612                                         let our_channel_close_key_hash = Hash160::from_data(&shutdown_pubkey.serialize());
1613                                         let shutdown_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1614                                         for (idx, output) in tx.output.iter().enumerate() {
1615                                                 if shutdown_script == output.script_pubkey {
1616                                                         return Some(SpendableOutputDescriptor::StaticOutput {
1617                                                                 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 },
1618                                                                 output: output.clone(),
1619                                                         });
1620                                                 }
1621                                         }
1622                                 }
1623                                 Storage::Watchtower { .. } => {
1624                                         //TODO: we need to ensure an offline client will generate the event when it
1625                                         // cames back online after only the watchtower saw the transaction
1626                                 }
1627                         }
1628                 }
1629                 None
1630         }
1631
1632         /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of
1633         /// the Channel was out-of-date.
1634         pub(super) fn get_latest_local_commitment_txn(&self) -> Vec<Transaction> {
1635                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1636                         let mut res = vec![local_tx.tx.clone()];
1637                         match self.key_storage {
1638                                 Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1639                                         res.append(&mut self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key)).0);
1640                                 },
1641                                 _ => panic!("Can only broadcast by local channelmonitor"),
1642                         };
1643                         res
1644                 } else {
1645                         Vec::new()
1646                 }
1647         }
1648
1649         fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>, Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)>) {
1650                 let mut watch_outputs = Vec::new();
1651                 let mut spendable_outputs = Vec::new();
1652                 let mut htlc_updated = Vec::new();
1653                 for tx in txn_matched {
1654                         if tx.input.len() == 1 {
1655                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1656                                 // commitment transactions and HTLC transactions will all only ever have one input,
1657                                 // which is an easy way to filter out any potential non-matching txn for lazy
1658                                 // filters.
1659                                 let prevout = &tx.input[0].previous_output;
1660                                 let mut txn: Vec<Transaction> = Vec::new();
1661                                 let funding_txo = match self.key_storage {
1662                                         Storage::Local { ref funding_info, .. } => {
1663                                                 funding_info.clone()
1664                                         }
1665                                         Storage::Watchtower { .. } => {
1666                                                 unimplemented!();
1667                                         }
1668                                 };
1669                                 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) {
1670                                         let (remote_txn, new_outputs, mut spendable_output, mut updated) = self.check_spend_remote_transaction(tx, height);
1671                                         txn = remote_txn;
1672                                         spendable_outputs.append(&mut spendable_output);
1673                                         if !new_outputs.1.is_empty() {
1674                                                 watch_outputs.push(new_outputs);
1675                                         }
1676                                         if txn.is_empty() {
1677                                                 let (local_txn, mut spendable_output, new_outputs) = self.check_spend_local_transaction(tx, height);
1678                                                 spendable_outputs.append(&mut spendable_output);
1679                                                 txn = local_txn;
1680                                                 if !new_outputs.1.is_empty() {
1681                                                         watch_outputs.push(new_outputs);
1682                                                 }
1683                                         }
1684                                         if !funding_txo.is_none() && txn.is_empty() {
1685                                                 if let Some(spendable_output) = self.check_spend_closing_transaction(tx) {
1686                                                         spendable_outputs.push(spendable_output);
1687                                                 }
1688                                         }
1689                                         if updated.len() > 0 {
1690                                                 htlc_updated.append(&mut updated);
1691                                         }
1692                                 } else {
1693                                         if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1694                                                 let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number);
1695                                                 if let Some(tx) = tx {
1696                                                         txn.push(tx);
1697                                                 }
1698                                                 if let Some(spendable_output) = spendable_output {
1699                                                         spendable_outputs.push(spendable_output);
1700                                                 }
1701                                         }
1702                                 }
1703                                 for tx in txn.iter() {
1704                                         broadcaster.broadcast_transaction(tx);
1705                                 }
1706                                 let mut updated = self.is_resolving_htlc_output(tx);
1707                                 if updated.len() > 0 {
1708                                         htlc_updated.append(&mut updated);
1709                                 }
1710                         }
1711                 }
1712                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1713                         if self.would_broadcast_at_height(height) {
1714                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1715                                 match self.key_storage {
1716                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1717                                                 let (txs, mut spendable_output, new_outputs) = self.broadcast_by_local_state(&cur_local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1718                                                 spendable_outputs.append(&mut spendable_output);
1719                                                 if !new_outputs.is_empty() {
1720                                                         watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
1721                                                 }
1722                                                 for tx in txs {
1723                                                         broadcaster.broadcast_transaction(&tx);
1724                                                 }
1725                                         },
1726                                         Storage::Watchtower { .. } => {
1727                                                 let (txs, mut spendable_output, new_outputs) = self.broadcast_by_local_state(&cur_local_tx, &None, &None);
1728                                                 spendable_outputs.append(&mut spendable_output);
1729                                                 if !new_outputs.is_empty() {
1730                                                         watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
1731                                                 }
1732                                                 for tx in txs {
1733                                                         broadcaster.broadcast_transaction(&tx);
1734                                                 }
1735                                         }
1736                                 }
1737                         }
1738                 }
1739                 self.last_block_hash = block_hash.clone();
1740                 (watch_outputs, spendable_outputs, htlc_updated)
1741         }
1742
1743         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1744                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1745                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1746                                 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1747                                 // chain with enough room to claim the HTLC without our counterparty being able to
1748                                 // time out the HTLC first.
1749                                 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1750                                 // concern is being able to claim the corresponding inbound HTLC (on another
1751                                 // channel) before it expires. In fact, we don't even really care if our
1752                                 // counterparty here claims such an outbound HTLC after it expired as long as we
1753                                 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1754                                 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1755                                 // we give ourselves a few blocks of headroom after expiration before going
1756                                 // on-chain for an expired HTLC.
1757                                 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1758                                 // from us until we've reached the point where we go on-chain with the
1759                                 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1760                                 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1761                                 //  aka outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS == height - CLTV_CLAIM_BUFFER
1762                                 //      inbound_cltv == height + CLTV_CLAIM_BUFFER
1763                                 //      outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS + CLTV_CLAIM_BUFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1764                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= inbound_cltv - outbound_cltv
1765                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= CLTV_EXPIRY_DELTA
1766                                 if ( htlc.offered && htlc.cltv_expiry + HTLC_FAIL_TIMEOUT_BLOCKS <= height) ||
1767                                    (!htlc.offered && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1768                                         return true;
1769                                 }
1770                         }
1771                 }
1772                 false
1773         }
1774
1775         /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
1776         /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
1777         fn is_resolving_htlc_output(&mut self, tx: &Transaction) -> Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)> {
1778                 let mut htlc_updated = Vec::new();
1779
1780                 'outer_loop: for input in &tx.input {
1781                         let mut payment_data = None;
1782
1783                         macro_rules! scan_commitment {
1784                                 ($htlc_outputs: expr, $htlc_sources: expr, $source: expr) => {
1785                                         for &(ref payment_hash, ref source, ref vout) in $htlc_sources.iter() {
1786                                                 if &Some(input.previous_output.vout) == vout {
1787                                                         log_trace!(self, "Input spending {}:{} resolves HTLC with payment hash {} from {}", input.previous_output.txid, input.previous_output.vout, log_bytes!(payment_hash.0), $source);
1788                                                         payment_data = Some((source.clone(), *payment_hash));
1789                                                 }
1790                                         }
1791                                         if payment_data.is_none() {
1792                                                 for htlc_output in $htlc_outputs {
1793                                                         if input.previous_output.vout == htlc_output.transaction_output_index {
1794                                                                 log_info!(self, "Input spending {}:{} in {} resolves inbound HTLC with timeout from {}", input.previous_output.txid, input.previous_output.vout, tx.txid(), $source);
1795                                                                 continue 'outer_loop;
1796                                                         }
1797                                                 }
1798                                         }
1799                                 }
1800                         }
1801
1802                         if let Some(ref current_local_signed_commitment_tx) = self.current_local_signed_commitment_tx {
1803                                 if input.previous_output.txid == current_local_signed_commitment_tx.txid {
1804                                         scan_commitment!(current_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a),
1805                                                 current_local_signed_commitment_tx.htlc_sources,
1806                                                 "our latest local commitment tx");
1807                                 }
1808                         }
1809                         if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
1810                                 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
1811                                         scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a),
1812                                                 prev_local_signed_commitment_tx.htlc_sources,
1813                                                 "our latest local commitment tx");
1814                                 }
1815                         }
1816                         if let Some(&(ref htlc_outputs, ref htlc_sources)) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
1817                                 scan_commitment!(htlc_outputs, htlc_sources, "remote commitment tx");
1818                         }
1819
1820                         // If tx isn't solving htlc output from local/remote commitment tx and htlc isn't outbound we don't need
1821                         // to broadcast solving backward
1822                         if let Some((source, payment_hash)) = payment_data {
1823                                 let mut payment_preimage = PaymentPreimage([0; 32]);
1824                                 if (input.witness.len() == 3 && input.witness[2].len() == OFFERED_HTLC_SCRIPT_WEIGHT && input.witness[1].len() == 33)
1825                                         || (input.witness.len() == 3 && input.witness[2].len() == ACCEPTED_HTLC_SCRIPT_WEIGHT && input.witness[1].len() == 33) {
1826                                         log_error!(self, "Remote used revocation sig to take a {} HTLC output at index {} from commitment_tx {}", if input.witness[2].len() == OFFERED_HTLC_SCRIPT_WEIGHT { "offered" } else { "accepted" }, input.previous_output.vout, input.previous_output.txid);
1827                                 } else if input.witness.len() == 5 && input.witness[4].len() == ACCEPTED_HTLC_SCRIPT_WEIGHT {
1828                                         payment_preimage.0.copy_from_slice(&tx.input[0].witness[3]);
1829                                         htlc_updated.push((source, Some(payment_preimage), payment_hash));
1830                                 } else if input.witness.len() == 3 && input.witness[2].len() == OFFERED_HTLC_SCRIPT_WEIGHT {
1831                                         payment_preimage.0.copy_from_slice(&tx.input[0].witness[1]);
1832                                         htlc_updated.push((source, Some(payment_preimage), payment_hash));
1833                                 } else {
1834                                         htlc_updated.push((source, None, payment_hash));
1835                                 }
1836                         }
1837                 }
1838                 htlc_updated
1839         }
1840 }
1841
1842 const MAX_ALLOC_SIZE: usize = 64*1024;
1843
1844 impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
1845         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
1846                 let secp_ctx = Secp256k1::new();
1847                 macro_rules! unwrap_obj {
1848                         ($key: expr) => {
1849                                 match $key {
1850                                         Ok(res) => res,
1851                                         Err(_) => return Err(DecodeError::InvalidValue),
1852                                 }
1853                         }
1854                 }
1855
1856                 let _ver: u8 = Readable::read(reader)?;
1857                 let min_ver: u8 = Readable::read(reader)?;
1858                 if min_ver > SERIALIZATION_VERSION {
1859                         return Err(DecodeError::UnknownVersion);
1860                 }
1861
1862                 let commitment_transaction_number_obscure_factor = <U48 as Readable<R>>::read(reader)?.0;
1863
1864                 let key_storage = match <u8 as Readable<R>>::read(reader)? {
1865                         0 => {
1866                                 let revocation_base_key = Readable::read(reader)?;
1867                                 let htlc_base_key = Readable::read(reader)?;
1868                                 let delayed_payment_base_key = Readable::read(reader)?;
1869                                 let payment_base_key = Readable::read(reader)?;
1870                                 let shutdown_pubkey = Readable::read(reader)?;
1871                                 let prev_latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1872                                         0 => None,
1873                                         1 => Some(Readable::read(reader)?),
1874                                         _ => return Err(DecodeError::InvalidValue),
1875                                 };
1876                                 let latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1877                                         0 => None,
1878                                         1 => Some(Readable::read(reader)?),
1879                                         _ => return Err(DecodeError::InvalidValue),
1880                                 };
1881                                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1882                                 // barely-init'd ChannelMonitors that we can't do anything with.
1883                                 let outpoint = OutPoint {
1884                                         txid: Readable::read(reader)?,
1885                                         index: Readable::read(reader)?,
1886                                 };
1887                                 let funding_info = Some((outpoint, Readable::read(reader)?));
1888                                 let current_remote_commitment_txid = match <u8 as Readable<R>>::read(reader)? {
1889                                         0 => None,
1890                                         1 => Some(Readable::read(reader)?),
1891                                         _ => return Err(DecodeError::InvalidValue),
1892                                 };
1893                                 let prev_remote_commitment_txid = match <u8 as Readable<R>>::read(reader)? {
1894                                         0 => None,
1895                                         1 => Some(Readable::read(reader)?),
1896                                         _ => return Err(DecodeError::InvalidValue),
1897                                 };
1898                                 Storage::Local {
1899                                         revocation_base_key,
1900                                         htlc_base_key,
1901                                         delayed_payment_base_key,
1902                                         payment_base_key,
1903                                         shutdown_pubkey,
1904                                         prev_latest_per_commitment_point,
1905                                         latest_per_commitment_point,
1906                                         funding_info,
1907                                         current_remote_commitment_txid,
1908                                         prev_remote_commitment_txid,
1909                                 }
1910                         },
1911                         _ => return Err(DecodeError::InvalidValue),
1912                 };
1913
1914                 let their_htlc_base_key = Some(Readable::read(reader)?);
1915                 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
1916
1917                 let their_cur_revocation_points = {
1918                         let first_idx = <U48 as Readable<R>>::read(reader)?.0;
1919                         if first_idx == 0 {
1920                                 None
1921                         } else {
1922                                 let first_point = Readable::read(reader)?;
1923                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
1924                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1925                                         Some((first_idx, first_point, None))
1926                                 } else {
1927                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, &second_point_slice)))))
1928                                 }
1929                         }
1930                 };
1931
1932                 let our_to_self_delay: u16 = Readable::read(reader)?;
1933                 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
1934
1935                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1936                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1937                         *secret = Readable::read(reader)?;
1938                         *idx = Readable::read(reader)?;
1939                 }
1940
1941                 macro_rules! read_htlc_in_commitment {
1942                         () => {
1943                                 {
1944                                         let offered: bool = Readable::read(reader)?;
1945                                         let amount_msat: u64 = Readable::read(reader)?;
1946                                         let cltv_expiry: u32 = Readable::read(reader)?;
1947                                         let payment_hash: PaymentHash = Readable::read(reader)?;
1948                                         let transaction_output_index: u32 = Readable::read(reader)?;
1949
1950                                         HTLCOutputInCommitment {
1951                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1952                                         }
1953                                 }
1954                         }
1955                 }
1956
1957                 macro_rules! read_htlc_source {
1958                         () => {
1959                                 {
1960                                         (Readable::read(reader)?, Readable::read(reader)?,
1961                                                 match <u8 as Readable<R>>::read(reader)? {
1962                                                         0 => None,
1963                                                         1 => Some(Readable::read(reader)?),
1964                                                         _ => return Err(DecodeError::InvalidValue),
1965                                                 }
1966                                         )
1967                                 }
1968                         }
1969                 }
1970
1971                 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
1972                 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
1973                 for _ in 0..remote_claimable_outpoints_len {
1974                         let txid: Sha256dHash = Readable::read(reader)?;
1975                         let outputs_count: u64 = Readable::read(reader)?;
1976                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 32));
1977                         for _ in 0..outputs_count {
1978                                 outputs.push(read_htlc_in_commitment!());
1979                         }
1980                         let sources_count: u64 = Readable::read(reader)?;
1981                         let mut sources = Vec::with_capacity(cmp::min(sources_count as usize, MAX_ALLOC_SIZE / 32));
1982                         for _ in 0..sources_count {
1983                                 sources.push(read_htlc_source!());
1984                         }
1985                         if let Some(_) = remote_claimable_outpoints.insert(txid, (outputs, sources)) {
1986                                 return Err(DecodeError::InvalidValue);
1987                         }
1988                 }
1989
1990                 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
1991                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
1992                 for _ in 0..remote_commitment_txn_on_chain_len {
1993                         let txid: Sha256dHash = Readable::read(reader)?;
1994                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1995                         let outputs_count = <u64 as Readable<R>>::read(reader)?;
1996                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
1997                         for _ in 0..outputs_count {
1998                                 outputs.push(Readable::read(reader)?);
1999                         }
2000                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2001                                 return Err(DecodeError::InvalidValue);
2002                         }
2003                 }
2004
2005                 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2006                 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2007                 for _ in 0..remote_hash_commitment_number_len {
2008                         let payment_hash: PaymentHash = Readable::read(reader)?;
2009                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
2010                         if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2011                                 return Err(DecodeError::InvalidValue);
2012                         }
2013                 }
2014
2015                 macro_rules! read_local_tx {
2016                         () => {
2017                                 {
2018                                         let tx = match Transaction::consensus_decode(reader.by_ref()) {
2019                                                 Ok(tx) => tx,
2020                                                 Err(e) => match e {
2021                                                         encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)),
2022                                                         _ => return Err(DecodeError::InvalidValue),
2023                                                 },
2024                                         };
2025
2026                                         if tx.input.is_empty() {
2027                                                 // Ensure tx didn't hit the 0-input ambiguity case.
2028                                                 return Err(DecodeError::InvalidValue);
2029                                         }
2030
2031                                         let revocation_key = Readable::read(reader)?;
2032                                         let a_htlc_key = Readable::read(reader)?;
2033                                         let b_htlc_key = Readable::read(reader)?;
2034                                         let delayed_payment_key = Readable::read(reader)?;
2035                                         let feerate_per_kw: u64 = Readable::read(reader)?;
2036
2037                                         let htlc_outputs_len: u64 = Readable::read(reader)?;
2038                                         let mut htlc_outputs = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
2039                                         for _ in 0..htlc_outputs_len {
2040                                                 let out = read_htlc_in_commitment!();
2041                                                 let sigs = (Readable::read(reader)?, Readable::read(reader)?);
2042                                                 htlc_outputs.push((out, sigs.0, sigs.1));
2043                                         }
2044
2045                                         let htlc_sources_len: u64 = Readable::read(reader)?;
2046                                         let mut htlc_sources = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
2047                                         for _ in 0..htlc_sources_len {
2048                                                 htlc_sources.push(read_htlc_source!());
2049                                         }
2050
2051                                         LocalSignedTx {
2052                                                 txid: tx.txid(),
2053                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs, htlc_sources
2054                                         }
2055                                 }
2056                         }
2057                 }
2058
2059                 let prev_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
2060                         0 => None,
2061                         1 => {
2062                                 Some(read_local_tx!())
2063                         },
2064                         _ => return Err(DecodeError::InvalidValue),
2065                 };
2066
2067                 let current_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
2068                         0 => None,
2069                         1 => {
2070                                 Some(read_local_tx!())
2071                         },
2072                         _ => return Err(DecodeError::InvalidValue),
2073                 };
2074
2075                 let current_remote_commitment_number = <U48 as Readable<R>>::read(reader)?.0;
2076
2077                 let payment_preimages_len: u64 = Readable::read(reader)?;
2078                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2079                 let mut sha = Sha256::new();
2080                 for _ in 0..payment_preimages_len {
2081                         let preimage: PaymentPreimage = Readable::read(reader)?;
2082                         sha.reset();
2083                         sha.input(&preimage.0[..]);
2084                         let mut hash = PaymentHash([0; 32]);
2085                         sha.result(&mut hash.0[..]);
2086                         if let Some(_) = payment_preimages.insert(hash, preimage) {
2087                                 return Err(DecodeError::InvalidValue);
2088                         }
2089                 }
2090
2091                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
2092                 let destination_script = Readable::read(reader)?;
2093
2094                 Ok((last_block_hash.clone(), ChannelMonitor {
2095                         commitment_transaction_number_obscure_factor,
2096
2097                         key_storage,
2098                         their_htlc_base_key,
2099                         their_delayed_payment_base_key,
2100                         their_cur_revocation_points,
2101
2102                         our_to_self_delay,
2103                         their_to_self_delay,
2104
2105                         old_secrets,
2106                         remote_claimable_outpoints,
2107                         remote_commitment_txn_on_chain,
2108                         remote_hash_commitment_number,
2109
2110                         prev_local_signed_commitment_tx,
2111                         current_local_signed_commitment_tx,
2112                         current_remote_commitment_number,
2113
2114                         payment_preimages,
2115
2116                         destination_script,
2117                         last_block_hash,
2118                         secp_ctx,
2119                         logger,
2120                 }))
2121         }
2122
2123 }
2124
2125 #[cfg(test)]
2126 mod tests {
2127         use bitcoin::blockdata::script::Script;
2128         use bitcoin::blockdata::transaction::Transaction;
2129         use crypto::digest::Digest;
2130         use hex;
2131         use ln::channelmanager::{PaymentPreimage, PaymentHash};
2132         use ln::channelmonitor::ChannelMonitor;
2133         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
2134         use util::sha2::Sha256;
2135         use util::test_utils::TestLogger;
2136         use secp256k1::key::{SecretKey,PublicKey};
2137         use secp256k1::{Secp256k1, Signature};
2138         use rand::{thread_rng,Rng};
2139         use std::sync::Arc;
2140
2141         #[test]
2142         fn test_per_commitment_storage() {
2143                 // Test vectors from BOLT 3:
2144                 let mut secrets: Vec<[u8; 32]> = Vec::new();
2145                 let mut monitor: ChannelMonitor;
2146                 let secp_ctx = Secp256k1::new();
2147                 let logger = Arc::new(TestLogger::new());
2148
2149                 macro_rules! test_secrets {
2150                         () => {
2151                                 let mut idx = 281474976710655;
2152                                 for secret in secrets.iter() {
2153                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
2154                                         idx -= 1;
2155                                 }
2156                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
2157                                 assert!(monitor.get_secret(idx).is_none());
2158                         };
2159                 }
2160
2161                 {
2162                         // insert_secret correct sequence
2163                         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());
2164                         secrets.clear();
2165
2166                         secrets.push([0; 32]);
2167                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2168                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2169                         test_secrets!();
2170
2171                         secrets.push([0; 32]);
2172                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2173                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2174                         test_secrets!();
2175
2176                         secrets.push([0; 32]);
2177                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2178                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2179                         test_secrets!();
2180
2181                         secrets.push([0; 32]);
2182                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2183                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2184                         test_secrets!();
2185
2186                         secrets.push([0; 32]);
2187                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2188                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2189                         test_secrets!();
2190
2191                         secrets.push([0; 32]);
2192                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2193                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2194                         test_secrets!();
2195
2196                         secrets.push([0; 32]);
2197                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2198                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2199                         test_secrets!();
2200
2201                         secrets.push([0; 32]);
2202                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2203                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
2204                         test_secrets!();
2205                 }
2206
2207                 {
2208                         // insert_secret #1 incorrect
2209                         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());
2210                         secrets.clear();
2211
2212                         secrets.push([0; 32]);
2213                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2214                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2215                         test_secrets!();
2216
2217                         secrets.push([0; 32]);
2218                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2219                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().0,
2220                                         "Previous secret did not match new one");
2221                 }
2222
2223                 {
2224                         // insert_secret #2 incorrect (#1 derived from incorrect)
2225                         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());
2226                         secrets.clear();
2227
2228                         secrets.push([0; 32]);
2229                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2230                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2231                         test_secrets!();
2232
2233                         secrets.push([0; 32]);
2234                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2235                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2236                         test_secrets!();
2237
2238                         secrets.push([0; 32]);
2239                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2240                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2241                         test_secrets!();
2242
2243                         secrets.push([0; 32]);
2244                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2245                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
2246                                         "Previous secret did not match new one");
2247                 }
2248
2249                 {
2250                         // insert_secret #3 incorrect
2251                         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());
2252                         secrets.clear();
2253
2254                         secrets.push([0; 32]);
2255                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2256                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2257                         test_secrets!();
2258
2259                         secrets.push([0; 32]);
2260                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2261                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2262                         test_secrets!();
2263
2264                         secrets.push([0; 32]);
2265                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2266                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2267                         test_secrets!();
2268
2269                         secrets.push([0; 32]);
2270                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2271                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
2272                                         "Previous secret did not match new one");
2273                 }
2274
2275                 {
2276                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
2277                         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());
2278                         secrets.clear();
2279
2280                         secrets.push([0; 32]);
2281                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2282                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2283                         test_secrets!();
2284
2285                         secrets.push([0; 32]);
2286                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2287                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2288                         test_secrets!();
2289
2290                         secrets.push([0; 32]);
2291                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2292                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2293                         test_secrets!();
2294
2295                         secrets.push([0; 32]);
2296                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
2297                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2298                         test_secrets!();
2299
2300                         secrets.push([0; 32]);
2301                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2302                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2303                         test_secrets!();
2304
2305                         secrets.push([0; 32]);
2306                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2307                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2308                         test_secrets!();
2309
2310                         secrets.push([0; 32]);
2311                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2312                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2313                         test_secrets!();
2314
2315                         secrets.push([0; 32]);
2316                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2317                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2318                                         "Previous secret did not match new one");
2319                 }
2320
2321                 {
2322                         // insert_secret #5 incorrect
2323                         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());
2324                         secrets.clear();
2325
2326                         secrets.push([0; 32]);
2327                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2328                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2329                         test_secrets!();
2330
2331                         secrets.push([0; 32]);
2332                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2333                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2334                         test_secrets!();
2335
2336                         secrets.push([0; 32]);
2337                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2338                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2339                         test_secrets!();
2340
2341                         secrets.push([0; 32]);
2342                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2343                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2344                         test_secrets!();
2345
2346                         secrets.push([0; 32]);
2347                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2348                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2349                         test_secrets!();
2350
2351                         secrets.push([0; 32]);
2352                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2353                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().0,
2354                                         "Previous secret did not match new one");
2355                 }
2356
2357                 {
2358                         // insert_secret #6 incorrect (5 derived from incorrect)
2359                         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());
2360                         secrets.clear();
2361
2362                         secrets.push([0; 32]);
2363                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2364                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2365                         test_secrets!();
2366
2367                         secrets.push([0; 32]);
2368                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2369                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2370                         test_secrets!();
2371
2372                         secrets.push([0; 32]);
2373                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2374                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2375                         test_secrets!();
2376
2377                         secrets.push([0; 32]);
2378                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2379                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2380                         test_secrets!();
2381
2382                         secrets.push([0; 32]);
2383                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2384                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2385                         test_secrets!();
2386
2387                         secrets.push([0; 32]);
2388                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2389                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2390                         test_secrets!();
2391
2392                         secrets.push([0; 32]);
2393                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2394                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2395                         test_secrets!();
2396
2397                         secrets.push([0; 32]);
2398                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2399                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2400                                         "Previous secret did not match new one");
2401                 }
2402
2403                 {
2404                         // insert_secret #7 incorrect
2405                         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());
2406                         secrets.clear();
2407
2408                         secrets.push([0; 32]);
2409                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2410                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2411                         test_secrets!();
2412
2413                         secrets.push([0; 32]);
2414                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2415                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2416                         test_secrets!();
2417
2418                         secrets.push([0; 32]);
2419                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2420                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2421                         test_secrets!();
2422
2423                         secrets.push([0; 32]);
2424                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2425                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2426                         test_secrets!();
2427
2428                         secrets.push([0; 32]);
2429                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2430                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2431                         test_secrets!();
2432
2433                         secrets.push([0; 32]);
2434                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2435                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2436                         test_secrets!();
2437
2438                         secrets.push([0; 32]);
2439                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2440                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2441                         test_secrets!();
2442
2443                         secrets.push([0; 32]);
2444                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2445                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2446                                         "Previous secret did not match new one");
2447                 }
2448
2449                 {
2450                         // insert_secret #8 incorrect
2451                         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());
2452                         secrets.clear();
2453
2454                         secrets.push([0; 32]);
2455                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2456                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2457                         test_secrets!();
2458
2459                         secrets.push([0; 32]);
2460                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2461                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2462                         test_secrets!();
2463
2464                         secrets.push([0; 32]);
2465                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2466                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2467                         test_secrets!();
2468
2469                         secrets.push([0; 32]);
2470                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2471                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2472                         test_secrets!();
2473
2474                         secrets.push([0; 32]);
2475                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2476                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2477                         test_secrets!();
2478
2479                         secrets.push([0; 32]);
2480                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2481                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2482                         test_secrets!();
2483
2484                         secrets.push([0; 32]);
2485                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2486                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2487                         test_secrets!();
2488
2489                         secrets.push([0; 32]);
2490                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2491                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2492                                         "Previous secret did not match new one");
2493                 }
2494         }
2495
2496         #[test]
2497         fn test_prune_preimages() {
2498                 let secp_ctx = Secp256k1::new();
2499                 let logger = Arc::new(TestLogger::new());
2500                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
2501
2502                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
2503                 macro_rules! dummy_keys {
2504                         () => {
2505                                 {
2506                                         TxCreationKeys {
2507                                                 per_commitment_point: dummy_key.clone(),
2508                                                 revocation_key: dummy_key.clone(),
2509                                                 a_htlc_key: dummy_key.clone(),
2510                                                 b_htlc_key: dummy_key.clone(),
2511                                                 a_delayed_payment_key: dummy_key.clone(),
2512                                                 b_payment_key: dummy_key.clone(),
2513                                         }
2514                                 }
2515                         }
2516                 }
2517                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2518
2519                 let mut preimages = Vec::new();
2520                 {
2521                         let mut rng  = thread_rng();
2522                         for _ in 0..20 {
2523                                 let mut preimage = PaymentPreimage([0; 32]);
2524                                 rng.fill_bytes(&mut preimage.0[..]);
2525                                 let mut sha = Sha256::new();
2526                                 sha.input(&preimage.0[..]);
2527                                 let mut hash = PaymentHash([0; 32]);
2528                                 sha.result(&mut hash.0[..]);
2529                                 preimages.push((preimage, hash));
2530                         }
2531                 }
2532
2533                 macro_rules! preimages_slice_to_htlc_outputs {
2534                         ($preimages_slice: expr) => {
2535                                 {
2536                                         let mut res = Vec::new();
2537                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
2538                                                 res.push(HTLCOutputInCommitment {
2539                                                         offered: true,
2540                                                         amount_msat: 0,
2541                                                         cltv_expiry: 0,
2542                                                         payment_hash: preimage.1.clone(),
2543                                                         transaction_output_index: idx as u32,
2544                                                 });
2545                                         }
2546                                         res
2547                                 }
2548                         }
2549                 }
2550                 macro_rules! preimages_to_local_htlcs {
2551                         ($preimages_slice: expr) => {
2552                                 {
2553                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2554                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
2555                                         res
2556                                 }
2557                         }
2558                 }
2559
2560                 macro_rules! test_preimages_exist {
2561                         ($preimages_slice: expr, $monitor: expr) => {
2562                                 for preimage in $preimages_slice {
2563                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
2564                                 }
2565                         }
2566                 }
2567
2568                 // Prune with one old state and a local commitment tx holding a few overlaps with the
2569                 // old state.
2570                 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());
2571                 monitor.set_their_to_self_delay(10);
2572
2573                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]), Vec::new());
2574                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), Vec::new(), 281474976710655, dummy_key);
2575                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), Vec::new(), 281474976710654, dummy_key);
2576                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), Vec::new(), 281474976710653, dummy_key);
2577                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), Vec::new(), 281474976710652, dummy_key);
2578                 for &(ref preimage, ref hash) in preimages.iter() {
2579                         monitor.provide_payment_preimage(hash, preimage);
2580                 }
2581
2582                 // Now provide a secret, pruning preimages 10-15
2583                 let mut secret = [0; 32];
2584                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2585                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2586                 assert_eq!(monitor.payment_preimages.len(), 15);
2587                 test_preimages_exist!(&preimages[0..10], monitor);
2588                 test_preimages_exist!(&preimages[15..20], monitor);
2589
2590                 // Now provide a further secret, pruning preimages 15-17
2591                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2592                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2593                 assert_eq!(monitor.payment_preimages.len(), 13);
2594                 test_preimages_exist!(&preimages[0..10], monitor);
2595                 test_preimages_exist!(&preimages[17..20], monitor);
2596
2597                 // Now update local commitment tx info, pruning only element 18 as we still care about the
2598                 // previous commitment tx's preimages too
2599                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]), Vec::new());
2600                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2601                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2602                 assert_eq!(monitor.payment_preimages.len(), 12);
2603                 test_preimages_exist!(&preimages[0..10], monitor);
2604                 test_preimages_exist!(&preimages[18..20], monitor);
2605
2606                 // But if we do it again, we'll prune 5-10
2607                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]), Vec::new());
2608                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2609                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2610                 assert_eq!(monitor.payment_preimages.len(), 5);
2611                 test_preimages_exist!(&preimages[0..5], monitor);
2612         }
2613
2614         // Further testing is done in the ChannelManager integration tests.
2615 }