_ 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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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 /// Number of blocks we wait on seeing a confirmed HTLC-Timeout or previous revoked commitment
 299 /// transaction before we fail corresponding inbound HTLCs. This prevents us from failing backwards
 300 /// and then getting a reorg resulting in us losing money.
 301 //TODO: We currently dont actually use this...we should
 302 pub(crate) const HTLC_FAIL_ANTI_REORG_DELAY: u32 = 6;
 303
 304 #[derive(Clone, PartialEq)]
 305 enum Storage {
 306         Local {
 307                 revocation_base_key: SecretKey,
 308                 htlc_base_key: SecretKey,
 309                 delayed_payment_base_key: SecretKey,
 310                 payment_base_key: SecretKey,
 311                 shutdown_pubkey: PublicKey,
 312                 prev_latest_per_commitment_point: Option<PublicKey>,
 313                 latest_per_commitment_point: Option<PublicKey>,
 314                 funding_info: Option<(OutPoint, Script)>,
 315                 current_remote_commitment_txid: Option<Sha256dHash>,
 316                 prev_remote_commitment_txid: Option<Sha256dHash>,
 317         },
 318         Watchtower {
 319                 revocation_base_key: PublicKey,
 320                 htlc_base_key: PublicKey,
 321         }
 322 }
 323
 324 #[derive(Clone, PartialEq)]
 325 struct LocalSignedTx {
 326         /// txid of the transaction in tx, just used to make comparison faster
 327         txid: Sha256dHash,
 328         tx: Transaction,
 329         revocation_key: PublicKey,
 330         a_htlc_key: PublicKey,
 331         b_htlc_key: PublicKey,
 332         delayed_payment_key: PublicKey,
 333         feerate_per_kw: u64,
 334         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 335         htlc_sources: Vec<(PaymentHash, HTLCSource, Option<u32>)>,
 336 }
 337
 338 const SERIALIZATION_VERSION: u8 = 1;
 339 const MIN_SERIALIZATION_VERSION: u8 = 1;
 340
 341 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 342 /// on-chain transactions to ensure no loss of funds occurs.
 343 ///
 344 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 345 /// information and are actively monitoring the chain.
 346 #[derive(Clone)]
 347 pub struct ChannelMonitor {
 348         commitment_transaction_number_obscure_factor: u64,
 349
 350         key_storage: Storage,
 351         their_htlc_base_key: Option<PublicKey>,
 352         their_delayed_payment_base_key: Option<PublicKey>,
 353         // first is the idx of the first of the two revocation points
 354         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 355
 356         our_to_self_delay: u16,
 357         their_to_self_delay: Option<u16>,
 358
 359         old_secrets: [([u8; 32], u64); 49],
 360         remote_claimable_outpoints: HashMap<Sha256dHash, (Vec<HTLCOutputInCommitment>, Vec<(PaymentHash, HTLCSource, Option<u32>)>)>,
 361         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 362         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 363         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 364         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 365         /// can be used to derive the revocation key and claim the transactions.
 366         remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
 367         /// Cache used to make pruning of payment_preimages faster.
 368         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 369         /// remote transactions (ie should remain pretty small).
 370         /// Serialized to disk but should generally not be sent to Watchtowers.
 371         remote_hash_commitment_number: HashMap<PaymentHash, u64>,
 372
 373         // We store two local commitment transactions to avoid any race conditions where we may update
 374         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 375         // various monitors for one channel being out of sync, and us broadcasting a local
 376         // transaction for which we have deleted claim information on some watchtowers.
 377         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 378         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 379
 380         // Used just for ChannelManager to make sure it has the latest channel data during
 381         // deserialization
 382         current_remote_commitment_number: u64,
 383
 384         payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
 385
 386         destination_script: Script,
 387
 388         // We simply modify last_block_hash in Channel's block_connected so that serialization is
 389         // consistent but hopefully the users' copy handles block_connected in a consistent way.
 390         // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
 391         // their last_block_hash from its state and not based on updated copies that didn't run through
 392         // the full block_connected).
 393         pub(crate) last_block_hash: Sha256dHash,
 394         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 395         logger: Arc<Logger>,
 396 }
 397
 398 #[cfg(any(test, feature = "fuzztarget"))]
 399 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 400 /// underlying object
 401 impl PartialEq for ChannelMonitor {
 402         fn eq(&self, other: &Self) -> bool {
 403                 if self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 404                         self.key_storage != other.key_storage ||
 405                         self.their_htlc_base_key != other.their_htlc_base_key ||
 406                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 407                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 408                         self.our_to_self_delay != other.our_to_self_delay ||
 409                         self.their_to_self_delay != other.their_to_self_delay ||
 410                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 411                         self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
 412                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 413                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 414                         self.current_remote_commitment_number != other.current_remote_commitment_number ||
 415                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 416                         self.payment_preimages != other.payment_preimages ||
 417                         self.destination_script != other.destination_script
 418                 {
 419                         false
 420                 } else {
 421                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 422                                 if secret != o_secret || idx != o_idx {
 423                                         return false
 424                                 }
 425                         }
 426                         true
 427                 }
 428         }
 429 }
 430
 431 impl ChannelMonitor {
 432         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 {
 433                 ChannelMonitor {
 434                         commitment_transaction_number_obscure_factor: 0,
 435
 436                         key_storage: Storage::Local {
 437                                 revocation_base_key: revocation_base_key.clone(),
 438                                 htlc_base_key: htlc_base_key.clone(),
 439                                 delayed_payment_base_key: delayed_payment_base_key.clone(),
 440                                 payment_base_key: payment_base_key.clone(),
 441                                 shutdown_pubkey: shutdown_pubkey.clone(),
 442                                 prev_latest_per_commitment_point: None,
 443                                 latest_per_commitment_point: None,
 444                                 funding_info: None,
 445                                 current_remote_commitment_txid: None,
 446                                 prev_remote_commitment_txid: None,
 447                         },
 448                         their_htlc_base_key: None,
 449                         their_delayed_payment_base_key: None,
 450                         their_cur_revocation_points: None,
 451
 452                         our_to_self_delay: our_to_self_delay,
 453                         their_to_self_delay: None,
 454
 455                         old_secrets: [([0; 32], 1 << 48); 49],
 456                         remote_claimable_outpoints: HashMap::new(),
 457                         remote_commitment_txn_on_chain: HashMap::new(),
 458                         remote_hash_commitment_number: HashMap::new(),
 459
 460                         prev_local_signed_commitment_tx: None,
 461                         current_local_signed_commitment_tx: None,
 462                         current_remote_commitment_number: 1 << 48,
 463
 464                         payment_preimages: HashMap::new(),
 465                         destination_script: destination_script,
 466
 467                         last_block_hash: Default::default(),
 468                         secp_ctx: Secp256k1::new(),
 469                         logger,
 470                 }
 471         }
 472
 473         #[inline]
 474         fn place_secret(idx: u64) -> u8 {
 475                 for i in 0..48 {
 476                         if idx & (1 << i) == (1 << i) {
 477                                 return i
 478                         }
 479                 }
 480                 48
 481         }
 482
 483         #[inline]
 484         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 485                 let mut res: [u8; 32] = secret;
 486                 for i in 0..bits {
 487                         let bitpos = bits - 1 - i;
 488                         if idx & (1 << bitpos) == (1 << bitpos) {
 489                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 490                                 let mut sha = Sha256::new();
 491                                 sha.input(&res);
 492                                 sha.result(&mut res);
 493                         }
 494                 }
 495                 res
 496         }
 497
 498         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
 499         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 500         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 501         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
 502                 let pos = ChannelMonitor::place_secret(idx);
 503                 for i in 0..pos {
 504                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 505                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 506                                 return Err(MonitorUpdateError("Previous secret did not match new one"));
 507                         }
 508                 }
 509                 if self.get_min_seen_secret() <= idx {
 510                         return Ok(());
 511                 }
 512                 self.old_secrets[pos as usize] = (secret, idx);
 513
 514                 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
 515                 // events for now-revoked/fulfilled HTLCs.
 516                 // TODO: We should probably consider whether we're really getting the next secret here.
 517                 if let Storage::Local { ref mut prev_remote_commitment_txid, .. } = self.key_storage {
 518                         if let Some(txid) = prev_remote_commitment_txid.take() {
 519                                 self.remote_claimable_outpoints.get_mut(&txid).unwrap().1 = Vec::new();
 520                         }
 521                 }
 522
 523                 if !self.payment_preimages.is_empty() {
 524                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 525                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 526                         let min_idx = self.get_min_seen_secret();
 527                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 528
 529                         self.payment_preimages.retain(|&k, _| {
 530                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 531                                         if k == htlc.payment_hash {
 532                                                 return true
 533                                         }
 534                                 }
 535                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 536                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 537                                                 if k == htlc.payment_hash {
 538                                                         return true
 539                                                 }
 540                                         }
 541                                 }
 542                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 543                                         if *cn < min_idx {
 544                                                 return true
 545                                         }
 546                                         true
 547                                 } else { false };
 548                                 if contains {
 549                                         remote_hash_commitment_number.remove(&k);
 550                                 }
 551                                 false
 552                         });
 553                 }
 554
 555                 Ok(())
 556         }
 557
 558         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 559         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 560         /// possibly future revocation/preimage information) to claim outputs where possible.
 561         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 562         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) {
 563                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 564                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 565                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 566                 // timeouts)
 567                 for ref htlc in &htlc_outputs {
 568                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 569                 }
 570
 571                 let new_txid = unsigned_commitment_tx.txid();
 572                 if let Storage::Local { ref mut current_remote_commitment_txid, ref mut prev_remote_commitment_txid, .. } = self.key_storage {
 573                         *prev_remote_commitment_txid = current_remote_commitment_txid.take();
 574                         *current_remote_commitment_txid = Some(new_txid);
 575                 }
 576                 self.remote_claimable_outpoints.insert(new_txid, (htlc_outputs, htlc_sources));
 577                 self.current_remote_commitment_number = commitment_number;
 578                 //TODO: Merge this into the other per-remote-transaction output storage stuff
 579                 match self.their_cur_revocation_points {
 580                         Some(old_points) => {
 581                                 if old_points.0 == commitment_number + 1 {
 582                                         self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
 583                                 } else if old_points.0 == commitment_number + 2 {
 584                                         if let Some(old_second_point) = old_points.2 {
 585                                                 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
 586                                         } else {
 587                                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 588                                         }
 589                                 } else {
 590                                         self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 591                                 }
 592                         },
 593                         None => {
 594                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 595                         }
 596                 }
 597         }
 598
 599         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 600         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 601         /// is important that any clones of this channel monitor (including remote clones) by kept
 602         /// up-to-date as our local commitment transaction is updated.
 603         /// Panics if set_their_to_self_delay has never been called.
 604         /// Also update Storage with latest local per_commitment_point to derive local_delayedkey in
 605         /// case of onchain HTLC tx
 606         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>)>) {
 607                 assert!(self.their_to_self_delay.is_some());
 608                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 609                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 610                         txid: signed_commitment_tx.txid(),
 611                         tx: signed_commitment_tx,
 612                         revocation_key: local_keys.revocation_key,
 613                         a_htlc_key: local_keys.a_htlc_key,
 614                         b_htlc_key: local_keys.b_htlc_key,
 615                         delayed_payment_key: local_keys.a_delayed_payment_key,
 616                         feerate_per_kw,
 617                         htlc_outputs,
 618                         htlc_sources,
 619                 });
 620
 621                 if let Storage::Local { ref mut latest_per_commitment_point, .. } = self.key_storage {
 622                         *latest_per_commitment_point = Some(local_keys.per_commitment_point);
 623                 } else {
 624                         panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 625                 }
 626         }
 627
 628         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 629         /// commitment_tx_infos which contain the payment hash have been revoked.
 630         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
 631                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 632         }
 633
 634         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 635         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 636         /// chain for new blocks/transactions.
 637         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 638                 match self.key_storage {
 639                         Storage::Local { ref funding_info, .. } => {
 640                                 if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 641                                 let our_funding_info = funding_info;
 642                                 if let Storage::Local { ref funding_info, .. } = other.key_storage {
 643                                         if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 644                                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 645                                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 646                                         if funding_info.as_ref().unwrap().0 != our_funding_info.as_ref().unwrap().0 {
 647                                                 return Err(MonitorUpdateError("Funding transaction outputs are not identical!"));
 648                                         }
 649                                 } else {
 650                                         return Err(MonitorUpdateError("Try to combine a Local monitor with a Watchtower one !"));
 651                                 }
 652                         },
 653                         Storage::Watchtower { .. } => {
 654                                 if let Storage::Watchtower { .. } = other.key_storage {
 655                                         unimplemented!();
 656                                 } else {
 657                                         return Err(MonitorUpdateError("Try to combine a Watchtower monitor with a Local one !"));
 658                                 }
 659                         },
 660                 }
 661                 let other_min_secret = other.get_min_seen_secret();
 662                 let our_min_secret = self.get_min_seen_secret();
 663                 if our_min_secret > other_min_secret {
 664                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
 665                 }
 666                 if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
 667                         if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
 668                                 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);
 669                                 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);
 670                                 if our_commitment_number >= other_commitment_number {
 671                                         self.key_storage = other.key_storage;
 672                                 }
 673                         }
 674                 }
 675                 // TODO: We should use current_remote_commitment_number and the commitment number out of
 676                 // local transactions to decide how to merge
 677                 if our_min_secret >= other_min_secret {
 678                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 679                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 680                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 681                         }
 682                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 683                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 684                         }
 685                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 686                                 self.current_local_signed_commitment_tx = Some(local_tx);
 687                         }
 688                         self.payment_preimages = other.payment_preimages;
 689                 }
 690
 691                 self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
 692                 Ok(())
 693         }
 694
 695         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 696         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 697                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 698                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 699         }
 700
 701         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 702         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 703         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 704         /// provides slightly better privacy.
 705         /// It's the responsibility of the caller to register outpoint and script with passing the former
 706         /// value as key to add_update_monitor.
 707         pub(super) fn set_funding_info(&mut self, new_funding_info: (OutPoint, Script)) {
 708                 match self.key_storage {
 709                         Storage::Local { ref mut funding_info, .. } => {
 710                                 *funding_info = Some(new_funding_info);
 711                         },
 712                         Storage::Watchtower { .. } => {
 713                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 714                         }
 715                 }
 716         }
 717
 718         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 719         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 720                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 721                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 722         }
 723
 724         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 725                 self.their_to_self_delay = Some(their_to_self_delay);
 726         }
 727
 728         pub(super) fn unset_funding_info(&mut self) {
 729                 match self.key_storage {
 730                         Storage::Local { ref mut funding_info, .. } => {
 731                                 *funding_info = None;
 732                         },
 733                         Storage::Watchtower { .. } => {
 734                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 735                         },
 736                 }
 737         }
 738
 739         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 740         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 741                 match self.key_storage {
 742                         Storage::Local { ref funding_info, .. } => {
 743                                 match funding_info {
 744                                         &Some((outpoint, _)) => Some(outpoint),
 745                                         &None => None
 746                                 }
 747                         },
 748                         Storage::Watchtower { .. } => {
 749                                 return None;
 750                         }
 751                 }
 752         }
 753
 754         /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
 755         /// Generally useful when deserializing as during normal operation the return values of
 756         /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
 757         /// that the get_funding_txo outpoint and transaction must also be monitored for!).
 758         pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
 759                 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
 760                 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
 761                         for (idx, output) in outputs.iter().enumerate() {
 762                                 res.push(((*txid).clone(), idx as u32, output));
 763                         }
 764                 }
 765                 res
 766         }
 767
 768         /// Serializes into a vec, with various modes for the exposed pub fns
 769         fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
 770                 //TODO: We still write out all the serialization here manually instead of using the fancy
 771                 //serialization framework we have, we should migrate things over to it.
 772                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 773                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 774
 775                 // Set in initial Channel-object creation, so should always be set by now:
 776                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
 777
 778                 match self.key_storage {
 779                         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 } => {
 780                                 writer.write_all(&[0; 1])?;
 781                                 writer.write_all(&revocation_base_key[..])?;
 782                                 writer.write_all(&htlc_base_key[..])?;
 783                                 writer.write_all(&delayed_payment_base_key[..])?;
 784                                 writer.write_all(&payment_base_key[..])?;
 785                                 writer.write_all(&shutdown_pubkey.serialize())?;
 786                                 if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point {
 787                                         writer.write_all(&[1; 1])?;
 788                                         writer.write_all(&prev_latest_per_commitment_point.serialize())?;
 789                                 } else {
 790                                         writer.write_all(&[0; 1])?;
 791                                 }
 792                                 if let Some(ref latest_per_commitment_point) = *latest_per_commitment_point {
 793                                         writer.write_all(&[1; 1])?;
 794                                         writer.write_all(&latest_per_commitment_point.serialize())?;
 795                                 } else {
 796                                         writer.write_all(&[0; 1])?;
 797                                 }
 798                                 match funding_info  {
 799                                         &Some((ref outpoint, ref script)) => {
 800                                                 writer.write_all(&outpoint.txid[..])?;
 801                                                 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
 802                                                 script.write(writer)?;
 803                                         },
 804                                         &None => {
 805                                                 debug_assert!(false, "Try to serialize a useless Local monitor !");
 806                                         },
 807                                 }
 808                                 if let Some(ref txid) = current_remote_commitment_txid {
 809                                         writer.write_all(&[1; 1])?;
 810                                         writer.write_all(&txid[..])?;
 811                                 } else {
 812                                         writer.write_all(&[0; 1])?;
 813                                 }
 814                                 if let Some(ref txid) = prev_remote_commitment_txid {
 815                                         writer.write_all(&[1; 1])?;
 816                                         writer.write_all(&txid[..])?;
 817                                 } else {
 818                                         writer.write_all(&[0; 1])?;
 819                                 }
 820                         },
 821                         Storage::Watchtower { .. } => unimplemented!(),
 822                 }
 823
 824                 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
 825                 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
 826
 827                 match self.their_cur_revocation_points {
 828                         Some((idx, pubkey, second_option)) => {
 829                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
 830                                 writer.write_all(&pubkey.serialize())?;
 831                                 match second_option {
 832                                         Some(second_pubkey) => {
 833                                                 writer.write_all(&second_pubkey.serialize())?;
 834                                         },
 835                                         None => {
 836                                                 writer.write_all(&[0; 33])?;
 837                                         },
 838                                 }
 839                         },
 840                         None => {
 841                                 writer.write_all(&byte_utils::be48_to_array(0))?;
 842                         },
 843                 }
 844
 845                 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
 846                 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
 847
 848                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 849                         writer.write_all(secret)?;
 850                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 851                 }
 852
 853                 macro_rules! serialize_htlc_in_commitment {
 854                         ($htlc_output: expr) => {
 855                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
 856                                 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
 857                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
 858                                 writer.write_all(&$htlc_output.payment_hash.0[..])?;
 859                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.transaction_output_index))?;
 860                         }
 861                 }
 862
 863                 macro_rules! serialize_htlc_source {
 864                         ($htlc_source: expr) => {
 865                                 $htlc_source.0.write(writer)?;
 866                                 $htlc_source.1.write(writer)?;
 867                                 if let &Some(ref txo) = &$htlc_source.2 {
 868                                         writer.write_all(&[1; 1])?;
 869                                         txo.write(writer)?;
 870                                 } else {
 871                                         writer.write_all(&[0; 1])?;
 872                                 }
 873                         }
 874                 }
 875
 876
 877                 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
 878                 for (ref txid, &(ref htlc_infos, ref htlc_sources)) in self.remote_claimable_outpoints.iter() {
 879                         writer.write_all(&txid[..])?;
 880                         writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
 881                         for ref htlc_output in htlc_infos.iter() {
 882                                 serialize_htlc_in_commitment!(htlc_output);
 883                         }
 884                         writer.write_all(&byte_utils::be64_to_array(htlc_sources.len() as u64))?;
 885                         for ref htlc_source in htlc_sources.iter() {
 886                                 serialize_htlc_source!(htlc_source);
 887                         }
 888                 }
 889
 890                 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
 891                 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
 892                         writer.write_all(&txid[..])?;
 893                         writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
 894                         (txouts.len() as u64).write(writer)?;
 895                         for script in txouts.iter() {
 896                                 script.write(writer)?;
 897                         }
 898                 }
 899
 900                 if for_local_storage {
 901                         writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
 902                         for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 903                                 writer.write_all(&payment_hash.0[..])?;
 904                                 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
 905                         }
 906                 } else {
 907                         writer.write_all(&byte_utils::be64_to_array(0))?;
 908                 }
 909
 910                 macro_rules! serialize_local_tx {
 911                         ($local_tx: expr) => {
 912                                 if let Err(e) = $local_tx.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 913                                         match e {
 914                                                 encode::Error::Io(e) => return Err(e),
 915                                                 _ => panic!("local tx must have been well-formed!"),
 916                                         }
 917                                 }
 918
 919                                 writer.write_all(&$local_tx.revocation_key.serialize())?;
 920                                 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
 921                                 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
 922                                 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
 923
 924                                 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
 925                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
 926                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 927                                         serialize_htlc_in_commitment!(htlc_output);
 928                                         writer.write_all(&their_sig.serialize_compact(&self.secp_ctx))?;
 929                                         writer.write_all(&our_sig.serialize_compact(&self.secp_ctx))?;
 930                                 }
 931                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_sources.len() as u64))?;
 932                                 for ref htlc_source in $local_tx.htlc_sources.iter() {
 933                                         serialize_htlc_source!(htlc_source);
 934                                 }
 935                         }
 936                 }
 937
 938                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 939                         writer.write_all(&[1; 1])?;
 940                         serialize_local_tx!(prev_local_tx);
 941                 } else {
 942                         writer.write_all(&[0; 1])?;
 943                 }
 944
 945                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 946                         writer.write_all(&[1; 1])?;
 947                         serialize_local_tx!(cur_local_tx);
 948                 } else {
 949                         writer.write_all(&[0; 1])?;
 950                 }
 951
 952                 if for_local_storage {
 953                         writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
 954                 } else {
 955                         writer.write_all(&byte_utils::be48_to_array(0))?;
 956                 }
 957
 958                 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
 959                 for payment_preimage in self.payment_preimages.values() {
 960                         writer.write_all(&payment_preimage.0[..])?;
 961                 }
 962
 963                 self.last_block_hash.write(writer)?;
 964                 self.destination_script.write(writer)?;
 965
 966                 Ok(())
 967         }
 968
 969         /// Writes this monitor into the given writer, suitable for writing to disk.
 970         ///
 971         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 972         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 973         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 974         /// common block that appears on your best chain as well as on the chain which contains the
 975         /// last block hash returned) upon deserializing the object!
 976         pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 977                 self.write(writer, true)
 978         }
 979
 980         /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
 981         ///
 982         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 983         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 984         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 985         /// common block that appears on your best chain as well as on the chain which contains the
 986         /// last block hash returned) upon deserializing the object!
 987         pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 988                 self.write(writer, false)
 989         }
 990
 991         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 992         //we want to leave out (eg funding_txo, etc).
 993
 994         /// Can only fail if idx is < get_min_seen_secret
 995         pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
 996                 for i in 0..self.old_secrets.len() {
 997                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 998                                 return Some(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 999                         }
1000                 }
1001                 assert!(idx < self.get_min_seen_secret());
1002                 None
1003         }
1004
1005         pub(super) fn get_min_seen_secret(&self) -> u64 {
1006                 //TODO This can be optimized?
1007                 let mut min = 1 << 48;
1008                 for &(_, idx) in self.old_secrets.iter() {
1009                         if idx < min {
1010                                 min = idx;
1011                         }
1012                 }
1013                 min
1014         }
1015
1016         pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1017                 self.current_remote_commitment_number
1018         }
1019
1020         pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1021                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1022                         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)
1023                 } else { 0xffff_ffff_ffff }
1024         }
1025
1026         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1027         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1028         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1029         /// HTLC-Success/HTLC-Timeout transactions.
1030         /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1031         /// revoked remote commitment tx
1032         fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>, Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)>)  {
1033                 // Most secp and related errors trying to create keys means we have no hope of constructing
1034                 // a spend transaction...so we return no transactions to broadcast
1035                 let mut txn_to_broadcast = Vec::new();
1036                 let mut watch_outputs = Vec::new();
1037                 let mut spendable_outputs = Vec::new();
1038                 let mut htlc_updated = Vec::new();
1039
1040                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1041                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1042
1043                 macro_rules! ignore_error {
1044                         ( $thing : expr ) => {
1045                                 match $thing {
1046                                         Ok(a) => a,
1047                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated)
1048                                 }
1049                         };
1050                 }
1051
1052                 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);
1053                 if commitment_number >= self.get_min_seen_secret() {
1054                         let secret = self.get_secret(commitment_number).unwrap();
1055                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1056                         let (revocation_pubkey, b_htlc_key, local_payment_key) = match self.key_storage {
1057                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, ref payment_base_key, .. } => {
1058                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1059                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1060                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))),
1061                                         Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
1062                                 },
1063                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
1064                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1065                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
1066                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)),
1067                                         None)
1068                                 },
1069                         };
1070                         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()));
1071                         let a_htlc_key = match self.their_htlc_base_key {
1072                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated),
1073                                 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)),
1074                         };
1075
1076                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1077                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1078
1079                         let local_payment_p2wpkh = if let Some(payment_key) = local_payment_key {
1080                                 // Note that the Network here is ignored as we immediately drop the address for the
1081                                 // script_pubkey version.
1082                                 let payment_hash160 = Hash160::from_data(&PublicKey::from_secret_key(&self.secp_ctx, &payment_key).serialize());
1083                                 Some(Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script())
1084                         } else { None };
1085
1086                         let mut total_value = 0;
1087                         let mut values = Vec::new();
1088                         let mut inputs = Vec::new();
1089                         let mut htlc_idxs = Vec::new();
1090
1091                         for (idx, outp) in tx.output.iter().enumerate() {
1092                                 if outp.script_pubkey == revokeable_p2wsh {
1093                                         inputs.push(TxIn {
1094                                                 previous_output: BitcoinOutPoint {
1095                                                         txid: commitment_txid,
1096                                                         vout: idx as u32,
1097                                                 },
1098                                                 script_sig: Script::new(),
1099                                                 sequence: 0xfffffffd,
1100                                                 witness: Vec::new(),
1101                                         });
1102                                         htlc_idxs.push(None);
1103                                         values.push(outp.value);
1104                                         total_value += outp.value;
1105                                 } else if Some(&outp.script_pubkey) == local_payment_p2wpkh.as_ref() {
1106                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1107                                                 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1108                                                 key: local_payment_key.unwrap(),
1109                                                 output: outp.clone(),
1110                                         });
1111                                 }
1112                         }
1113
1114                         macro_rules! sign_input {
1115                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
1116                                         {
1117                                                 let (sig, redeemscript) = match self.key_storage {
1118                                                         Storage::Local { ref revocation_base_key, .. } => {
1119                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
1120                                                                         let htlc = &per_commitment_option.unwrap().0[$htlc_idx.unwrap()];
1121                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
1122                                                                 };
1123                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1124                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1125                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
1126                                                         },
1127                                                         Storage::Watchtower { .. } => {
1128                                                                 unimplemented!();
1129                                                         }
1130                                                 };
1131                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1132                                                 $input.witness[0].push(SigHashType::All as u8);
1133                                                 if $htlc_idx.is_none() {
1134                                                         $input.witness.push(vec!(1));
1135                                                 } else {
1136                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
1137                                                 }
1138                                                 $input.witness.push(redeemscript.into_bytes());
1139                                         }
1140                                 }
1141                         }
1142
1143                         if let Some(&(ref per_commitment_data, _)) = per_commitment_option {
1144                                 inputs.reserve_exact(per_commitment_data.len());
1145
1146                                 for (idx, ref htlc) in per_commitment_data.iter().enumerate() {
1147                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1148                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
1149                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1150                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1151                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); // Corrupted per_commitment_data, fuck this user
1152                                         }
1153                                         let input = TxIn {
1154                                                 previous_output: BitcoinOutPoint {
1155                                                         txid: commitment_txid,
1156                                                         vout: htlc.transaction_output_index,
1157                                                 },
1158                                                 script_sig: Script::new(),
1159                                                 sequence: 0xfffffffd,
1160                                                 witness: Vec::new(),
1161                                         };
1162                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1163                                                 inputs.push(input);
1164                                                 htlc_idxs.push(Some(idx));
1165                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1166                                                 total_value += htlc.amount_msat / 1000;
1167                                         } else {
1168                                                 let mut single_htlc_tx = Transaction {
1169                                                         version: 2,
1170                                                         lock_time: 0,
1171                                                         input: vec![input],
1172                                                         output: vec!(TxOut {
1173                                                                 script_pubkey: self.destination_script.clone(),
1174                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1175                                                         }),
1176                                                 };
1177                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1178                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1179                                                 txn_to_broadcast.push(single_htlc_tx);
1180                                         }
1181                                 }
1182                         }
1183
1184                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1185                                 // We're definitely a remote commitment transaction!
1186                                 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());
1187                                 watch_outputs.append(&mut tx.output.clone());
1188                                 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1189                         }
1190                         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
1191
1192                         let outputs = vec!(TxOut {
1193                                 script_pubkey: self.destination_script.clone(),
1194                                 value: total_value, //TODO: - fee
1195                         });
1196                         let mut spend_tx = Transaction {
1197                                 version: 2,
1198                                 lock_time: 0,
1199                                 input: inputs,
1200                                 output: outputs,
1201                         };
1202
1203                         let mut values_drain = values.drain(..);
1204                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1205
1206                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1207                                 let value = values_drain.next().unwrap();
1208                                 sign_input!(sighash_parts, input, htlc_idx, value);
1209                         }
1210
1211                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1212                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1213                                 output: spend_tx.output[0].clone(),
1214                         });
1215                         txn_to_broadcast.push(spend_tx);
1216
1217                         // TODO: We really should only fail backwards after our revocation claims have been
1218                         // confirmed, but we also need to do more other tracking of in-flight pre-confirm
1219                         // on-chain claims, so we can do that at the same time.
1220                         if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
1221                                 if let &Some(ref txid) = current_remote_commitment_txid {
1222                                         if let Some(&(_, ref latest_outpoints)) = self.remote_claimable_outpoints.get(&txid) {
1223                                                 for &(ref payment_hash, ref source, _) in latest_outpoints.iter() {
1224                                                         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));
1225                                                         htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
1226                                                 }
1227                                         }
1228                                 }
1229                                 if let &Some(ref txid) = prev_remote_commitment_txid {
1230                                         if let Some(&(_, ref prev_outpoint)) = self.remote_claimable_outpoints.get(&txid) {
1231                                                 for &(ref payment_hash, ref source, _) in prev_outpoint.iter() {
1232                                                         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));
1233                                                         htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
1234                                                 }
1235                                         }
1236                                 }
1237                         }
1238                         // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1239                 } else if let Some(per_commitment_data) = per_commitment_option {
1240                         // While this isn't useful yet, there is a potential race where if a counterparty
1241                         // revokes a state at the same time as the commitment transaction for that state is
1242                         // confirmed, and the watchtower receives the block before the user, the user could
1243                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1244                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1245                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1246                         // insert it here.
1247                         watch_outputs.append(&mut tx.output.clone());
1248                         self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1249
1250                         if let Some(revocation_points) = self.their_cur_revocation_points {
1251                                 let revocation_point_option =
1252                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1253                                         else if let Some(point) = revocation_points.2.as_ref() {
1254                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1255                                         } else { None };
1256                                 if let Some(revocation_point) = revocation_point_option {
1257                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1258                                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, .. } => {
1259                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1260                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1261                                                 },
1262                                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
1263                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1264                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1265                                                 },
1266                                         };
1267                                         let a_htlc_key = match self.their_htlc_base_key {
1268                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated),
1269                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1270                                         };
1271
1272                                         for (idx, outp) in tx.output.iter().enumerate() {
1273                                                 if outp.script_pubkey.is_v0_p2wpkh() {
1274                                                         match self.key_storage {
1275                                                                 Storage::Local { ref payment_base_key, .. } => {
1276                                                                         if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &revocation_point, &payment_base_key) {
1277                                                                                 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1278                                                                                         outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1279                                                                                         key: local_key,
1280                                                                                         output: outp.clone(),
1281                                                                                 });
1282                                                                         }
1283                                                                 },
1284                                                                 Storage::Watchtower { .. } => {}
1285                                                         }
1286                                                         break; // Only to_remote ouput is claimable
1287                                                 }
1288                                         }
1289
1290                                         let mut total_value = 0;
1291                                         let mut values = Vec::new();
1292                                         let mut inputs = Vec::new();
1293
1294                                         macro_rules! sign_input {
1295                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1296                                                         {
1297                                                                 let (sig, redeemscript) = match self.key_storage {
1298                                                                         Storage::Local { ref htlc_base_key, .. } => {
1299                                                                                 let htlc = &per_commitment_option.unwrap().0[$input.sequence as usize];
1300                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1301                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1302                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1303                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1304                                                                         },
1305                                                                         Storage::Watchtower { .. } => {
1306                                                                                 unimplemented!();
1307                                                                         }
1308                                                                 };
1309                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1310                                                                 $input.witness[0].push(SigHashType::All as u8);
1311                                                                 $input.witness.push($preimage);
1312                                                                 $input.witness.push(redeemscript.into_bytes());
1313                                                         }
1314                                                 }
1315                                         }
1316
1317                                         for (idx, ref htlc) in per_commitment_data.0.iter().enumerate() {
1318                                                 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1319                                                 if htlc.transaction_output_index as usize >= tx.output.len() ||
1320                                                                 tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1321                                                                 tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1322                                                         return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); // Corrupted per_commitment_data, fuck this user
1323                                                 }
1324                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1325                                                         let input = TxIn {
1326                                                                 previous_output: BitcoinOutPoint {
1327                                                                         txid: commitment_txid,
1328                                                                         vout: htlc.transaction_output_index,
1329                                                                 },
1330                                                                 script_sig: Script::new(),
1331                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1332                                                                 witness: Vec::new(),
1333                                                         };
1334                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1335                                                                 inputs.push(input);
1336                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1337                                                                 total_value += htlc.amount_msat / 1000;
1338                                                         } else {
1339                                                                 let mut single_htlc_tx = Transaction {
1340                                                                         version: 2,
1341                                                                         lock_time: 0,
1342                                                                         input: vec![input],
1343                                                                         output: vec!(TxOut {
1344                                                                                 script_pubkey: self.destination_script.clone(),
1345                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1346                                                                         }),
1347                                                                 };
1348                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1349                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.0.to_vec());
1350                                                                 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1351                                                                         outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
1352                                                                         output: single_htlc_tx.output[0].clone(),
1353                                                                 });
1354                                                                 txn_to_broadcast.push(single_htlc_tx);
1355                                                         }
1356                                                 }
1357                                                 if !htlc.offered {
1358                                                         // TODO: If the HTLC has already expired, potentially merge it with the
1359                                                         // rest of the claim transaction, as above.
1360                                                         let input = TxIn {
1361                                                                 previous_output: BitcoinOutPoint {
1362                                                                         txid: commitment_txid,
1363                                                                         vout: htlc.transaction_output_index,
1364                                                                 },
1365                                                                 script_sig: Script::new(),
1366                                                                 sequence: idx as u32,
1367                                                                 witness: Vec::new(),
1368                                                         };
1369                                                         let mut timeout_tx = Transaction {
1370                                                                 version: 2,
1371                                                                 lock_time: htlc.cltv_expiry,
1372                                                                 input: vec![input],
1373                                                                 output: vec!(TxOut {
1374                                                                         script_pubkey: self.destination_script.clone(),
1375                                                                         value: htlc.amount_msat / 1000,
1376                                                                 }),
1377                                                         };
1378                                                         let sighash_parts = bip143::SighashComponents::new(&timeout_tx);
1379                                                         sign_input!(sighash_parts, timeout_tx.input[0], htlc.amount_msat / 1000, vec![0]);
1380                                                         txn_to_broadcast.push(timeout_tx);
1381                                                 }
1382                                         }
1383
1384                                         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
1385
1386                                         let outputs = vec!(TxOut {
1387                                                 script_pubkey: self.destination_script.clone(),
1388                                                 value: total_value, //TODO: - fee
1389                                         });
1390                                         let mut spend_tx = Transaction {
1391                                                 version: 2,
1392                                                 lock_time: 0,
1393                                                 input: inputs,
1394                                                 output: outputs,
1395                                         };
1396
1397                                         let mut values_drain = values.drain(..);
1398                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1399
1400                                         for input in spend_tx.input.iter_mut() {
1401                                                 let value = values_drain.next().unwrap();
1402                                                 sign_input!(sighash_parts, input, value.0, (value.1).0.to_vec());
1403                                         }
1404
1405                                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1406                                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1407                                                 output: spend_tx.output[0].clone(),
1408                                         });
1409                                         txn_to_broadcast.push(spend_tx);
1410
1411                                         // TODO: We need to fail back HTLCs that were't included in the broadcast
1412                                         // commitment transaction, either because they didn't meet dust or because a
1413                                         // stale (but not yet revoked) commitment transaction was broadcast!
1414                                 }
1415                         }
1416                 }
1417
1418                 (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated)
1419         }
1420
1421         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1422         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> (Option<Transaction>, Option<SpendableOutputDescriptor>) {
1423                 if tx.input.len() != 1 || tx.output.len() != 1 {
1424                         return (None, None)
1425                 }
1426
1427                 macro_rules! ignore_error {
1428                         ( $thing : expr ) => {
1429                                 match $thing {
1430                                         Ok(a) => a,
1431                                         Err(_) => return (None, None)
1432                                 }
1433                         };
1434                 }
1435
1436                 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (None, None); };
1437                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1438                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1439                 let revocation_pubkey = match self.key_storage {
1440                         Storage::Local { ref revocation_base_key, .. } => {
1441                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1442                         },
1443                         Storage::Watchtower { ref revocation_base_key, .. } => {
1444                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1445                         },
1446                 };
1447                 let delayed_key = match self.their_delayed_payment_base_key {
1448                         None => return (None, None),
1449                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1450                 };
1451                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1452                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1453                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1454
1455                 let mut inputs = Vec::new();
1456                 let mut amount = 0;
1457
1458                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1459                         inputs.push(TxIn {
1460                                 previous_output: BitcoinOutPoint {
1461                                         txid: htlc_txid,
1462                                         vout: 0,
1463                                 },
1464                                 script_sig: Script::new(),
1465                                 sequence: 0xfffffffd,
1466                                 witness: Vec::new(),
1467                         });
1468                         amount = tx.output[0].value;
1469                 }
1470
1471                 if !inputs.is_empty() {
1472                         let outputs = vec!(TxOut {
1473                                 script_pubkey: self.destination_script.clone(),
1474                                 value: amount, //TODO: - fee
1475                         });
1476
1477                         let mut spend_tx = Transaction {
1478                                 version: 2,
1479                                 lock_time: 0,
1480                                 input: inputs,
1481                                 output: outputs,
1482                         };
1483
1484                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1485
1486                         let sig = match self.key_storage {
1487                                 Storage::Local { ref revocation_base_key, .. } => {
1488                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1489                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1490                                         self.secp_ctx.sign(&sighash, &revocation_key)
1491                                 }
1492                                 Storage::Watchtower { .. } => {
1493                                         unimplemented!();
1494                                 }
1495                         };
1496                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1497                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1498                         spend_tx.input[0].witness.push(vec!(1));
1499                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1500
1501                         let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
1502                         let output = spend_tx.output[0].clone();
1503                         (Some(spend_tx), Some(SpendableOutputDescriptor::StaticOutput { outpoint, output }))
1504                 } else { (None, None) }
1505         }
1506
1507         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>) {
1508                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1509                 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1510                 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1511
1512                 macro_rules! add_dynamic_output {
1513                         ($father_tx: expr, $vout: expr) => {
1514                                 if let Some(ref per_commitment_point) = *per_commitment_point {
1515                                         if let Some(ref delayed_payment_base_key) = *delayed_payment_base_key {
1516                                                 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, per_commitment_point, delayed_payment_base_key) {
1517                                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WSH {
1518                                                                 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1519                                                                 key: local_delayedkey,
1520                                                                 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1521                                                                 to_self_delay: self.our_to_self_delay,
1522                                                                 output: $father_tx.output[$vout as usize].clone(),
1523                                                         });
1524                                                 }
1525                                         }
1526                                 }
1527                         }
1528                 }
1529
1530
1531                 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1532                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1533                 for (idx, output) in local_tx.tx.output.iter().enumerate() {
1534                         if output.script_pubkey == revokeable_p2wsh {
1535                                 add_dynamic_output!(local_tx.tx, idx as u32);
1536                                 break;
1537                         }
1538                 }
1539
1540                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1541                         if htlc.offered {
1542                                 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);
1543
1544                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1545
1546                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1547                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1548                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1549                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1550
1551                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1552                                 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());
1553
1554                                 add_dynamic_output!(htlc_timeout_tx, 0);
1555                                 res.push(htlc_timeout_tx);
1556                         } else {
1557                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1558                                         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);
1559
1560                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1561
1562                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1563                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1564                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1565                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1566
1567                                         htlc_success_tx.input[0].witness.push(payment_preimage.0.to_vec());
1568                                         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());
1569
1570                                         add_dynamic_output!(htlc_success_tx, 0);
1571                                         res.push(htlc_success_tx);
1572                                 }
1573                         }
1574                         watch_outputs.push(local_tx.tx.output[htlc.transaction_output_index as usize].clone());
1575                 }
1576
1577                 (res, spendable_outputs, watch_outputs)
1578         }
1579
1580         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1581         /// revoked using data in local_claimable_outpoints.
1582         /// Should not be used if check_spend_revoked_transaction succeeds.
1583         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>, (Sha256dHash, Vec<TxOut>)) {
1584                 let commitment_txid = tx.txid();
1585                 // TODO: If we find a match here we need to fail back HTLCs that were't included in the
1586                 // broadcast commitment transaction, either because they didn't meet dust or because they
1587                 // weren't yet included in our commitment transaction(s).
1588                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1589                         if local_tx.txid == commitment_txid {
1590                                 match self.key_storage {
1591                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1592                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1593                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1594                                         },
1595                                         Storage::Watchtower { .. } => {
1596                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, &None, &None);
1597                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1598                                         }
1599                                 }
1600                         }
1601                 }
1602                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1603                         if local_tx.txid == commitment_txid {
1604                                 match self.key_storage {
1605                                         Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1606                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key));
1607                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1608                                         },
1609                                         Storage::Watchtower { .. } => {
1610                                                 let (local_txn, spendable_outputs, watch_outputs) = self.broadcast_by_local_state(local_tx, &None, &None);
1611                                                 return (local_txn, spendable_outputs, (commitment_txid, watch_outputs));
1612                                         }
1613                                 }
1614                         }
1615                 }
1616                 (Vec::new(), Vec::new(), (commitment_txid, Vec::new()))
1617         }
1618
1619         /// Generate a spendable output event when closing_transaction get registered onchain.
1620         fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option<SpendableOutputDescriptor> {
1621                 if tx.input[0].sequence == 0xFFFFFFFF && !tx.input[0].witness.is_empty() && tx.input[0].witness.last().unwrap().len() == 71 {
1622                         match self.key_storage {
1623                                 Storage::Local { ref shutdown_pubkey, .. } =>  {
1624                                         let our_channel_close_key_hash = Hash160::from_data(&shutdown_pubkey.serialize());
1625                                         let shutdown_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1626                                         for (idx, output) in tx.output.iter().enumerate() {
1627                                                 if shutdown_script == output.script_pubkey {
1628                                                         return Some(SpendableOutputDescriptor::StaticOutput {
1629                                                                 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 },
1630                                                                 output: output.clone(),
1631                                                         });
1632                                                 }
1633                                         }
1634                                 }
1635                                 Storage::Watchtower { .. } => {
1636                                         //TODO: we need to ensure an offline client will generate the event when it
1637                                         // cames back online after only the watchtower saw the transaction
1638                                 }
1639                         }
1640                 }
1641                 None
1642         }
1643
1644         /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of
1645         /// the Channel was out-of-date.
1646         pub(super) fn get_latest_local_commitment_txn(&self) -> Vec<Transaction> {
1647                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1648                         let mut res = vec![local_tx.tx.clone()];
1649                         match self.key_storage {
1650                                 Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1651                                         res.append(&mut self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key)).0);
1652                                 },
1653                                 _ => panic!("Can only broadcast by local channelmonitor"),
1654                         };
1655                         res
1656                 } else {
1657                         Vec::new()
1658                 }
1659         }
1660
1661         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)>) {
1662                 let mut watch_outputs = Vec::new();
1663                 let mut spendable_outputs = Vec::new();
1664                 let mut htlc_updated = Vec::new();
1665                 for tx in txn_matched {
1666                         if tx.input.len() == 1 {
1667                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1668                                 // commitment transactions and HTLC transactions will all only ever have one input,
1669                                 // which is an easy way to filter out any potential non-matching txn for lazy
1670                                 // filters.
1671                                 let prevout = &tx.input[0].previous_output;
1672                                 let mut txn: Vec<Transaction> = Vec::new();
1673                                 let funding_txo = match self.key_storage {
1674                                         Storage::Local { ref funding_info, .. } => {
1675                                                 funding_info.clone()
1676                                         }
1677                                         Storage::Watchtower { .. } => {
1678                                                 unimplemented!();
1679                                         }
1680                                 };
1681                                 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) {
1682                                         let (remote_txn, new_outputs, mut spendable_output, mut updated) = self.check_spend_remote_transaction(tx, height);
1683                                         txn = remote_txn;
1684                                         spendable_outputs.append(&mut spendable_output);
1685                                         if !new_outputs.1.is_empty() {
1686                                                 watch_outputs.push(new_outputs);
1687                                         }
1688                                         if txn.is_empty() {
1689                                                 let (local_txn, mut spendable_output, new_outputs) = self.check_spend_local_transaction(tx, height);
1690                                                 spendable_outputs.append(&mut spendable_output);
1691                                                 txn = local_txn;
1692                                                 if !new_outputs.1.is_empty() {
1693                                                         watch_outputs.push(new_outputs);
1694                                                 }
1695                                         }
1696                                         if !funding_txo.is_none() && txn.is_empty() {
1697                                                 if let Some(spendable_output) = self.check_spend_closing_transaction(tx) {
1698                                                         spendable_outputs.push(spendable_output);
1699                                                 }
1700                                         }
1701                                         if updated.len() > 0 {
1702                                                 htlc_updated.append(&mut updated);
1703                                         }
1704                                 } else {
1705                                         if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1706                                                 let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number);
1707                                                 if let Some(tx) = tx {
1708                                                         txn.push(tx);
1709                                                 }
1710                                                 if let Some(spendable_output) = spendable_output {
1711                                                         spendable_outputs.push(spendable_output);
1712                                                 }
1713                                         }
1714                                 }
1715                                 for tx in txn.iter() {
1716                                         broadcaster.broadcast_transaction(tx);
1717                                 }
1718                                 let mut updated = self.is_resolving_htlc_output(tx);
1719                                 if updated.len() > 0 {
1720                                         htlc_updated.append(&mut updated);
1721                                 }
1722                         }
1723                 }
1724                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1725                         if self.would_broadcast_at_height(height) {
1726                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1727                                 match self.key_storage {
1728                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1729                                                 let (txs, mut spendable_output, new_outputs) = self.broadcast_by_local_state(&cur_local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1730                                                 spendable_outputs.append(&mut spendable_output);
1731                                                 if !new_outputs.is_empty() {
1732                                                         watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
1733                                                 }
1734                                                 for tx in txs {
1735                                                         broadcaster.broadcast_transaction(&tx);
1736                                                 }
1737                                         },
1738                                         Storage::Watchtower { .. } => {
1739                                                 let (txs, mut spendable_output, new_outputs) = self.broadcast_by_local_state(&cur_local_tx, &None, &None);
1740                                                 spendable_outputs.append(&mut spendable_output);
1741                                                 if !new_outputs.is_empty() {
1742                                                         watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
1743                                                 }
1744                                                 for tx in txs {
1745                                                         broadcaster.broadcast_transaction(&tx);
1746                                                 }
1747                                         }
1748                                 }
1749                         }
1750                 }
1751                 self.last_block_hash = block_hash.clone();
1752                 (watch_outputs, spendable_outputs, htlc_updated)
1753         }
1754
1755         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1756                 // TODO: We need to consider HTLCs which weren't included in latest local commitment
1757                 // transaction (or in any of the latest two local commitment transactions). This probably
1758                 // needs to use the same logic as the revoked-tx-announe logic - checking the last two
1759                 // remote commitment transactions. This probably has implications for what data we need to
1760                 // store in local commitment transactions.
1761                 // TODO: We need to consider HTLCs which were below dust threshold here - while they don't
1762                 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1763                 // to the source, and if we don't fail the channel we will have to ensure that the next
1764                 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1765                 // easier to just fail the channel as this case should be rare enough anyway.
1766                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1767                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1768                                 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1769                                 // chain with enough room to claim the HTLC without our counterparty being able to
1770                                 // time out the HTLC first.
1771                                 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1772                                 // concern is being able to claim the corresponding inbound HTLC (on another
1773                                 // channel) before it expires. In fact, we don't even really care if our
1774                                 // counterparty here claims such an outbound HTLC after it expired as long as we
1775                                 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1776                                 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1777                                 // we give ourselves a few blocks of headroom after expiration before going
1778                                 // on-chain for an expired HTLC.
1779                                 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1780                                 // from us until we've reached the point where we go on-chain with the
1781                                 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1782                                 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1783                                 //  aka outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS == height - CLTV_CLAIM_BUFFER
1784                                 //      inbound_cltv == height + CLTV_CLAIM_BUFFER
1785                                 //      outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS + CLTV_CLAIM_BUFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1786                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= inbound_cltv - outbound_cltv
1787                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= CLTV_EXPIRY_DELTA
1788                                 if ( htlc.offered && htlc.cltv_expiry + HTLC_FAIL_TIMEOUT_BLOCKS <= height) ||
1789                                    (!htlc.offered && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1790                                         return true;
1791                                 }
1792                         }
1793                 }
1794                 false
1795         }
1796
1797         /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
1798         /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
1799         fn is_resolving_htlc_output(&mut self, tx: &Transaction) -> Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)> {
1800                 let mut htlc_updated = Vec::new();
1801
1802                 'outer_loop: for input in &tx.input {
1803                         let mut payment_data = None;
1804
1805                         macro_rules! scan_commitment {
1806                                 ($htlc_outputs: expr, $htlc_sources: expr, $source: expr) => {
1807                                         for &(ref payment_hash, ref source, ref vout) in $htlc_sources.iter() {
1808                                                 if &Some(input.previous_output.vout) == vout {
1809                                                         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);
1810                                                         payment_data = Some((source.clone(), *payment_hash));
1811                                                 }
1812                                         }
1813                                         if payment_data.is_none() {
1814                                                 for htlc_output in $htlc_outputs {
1815                                                         if input.previous_output.vout == htlc_output.transaction_output_index {
1816                                                                 log_info!(self, "Input spending {}:{} in {} resolves inbound HTLC with timeout from {}", input.previous_output.txid, input.previous_output.vout, tx.txid(), $source);
1817                                                                 continue 'outer_loop;
1818                                                         }
1819                                                 }
1820                                         }
1821                                 }
1822                         }
1823
1824                         if let Some(ref current_local_signed_commitment_tx) = self.current_local_signed_commitment_tx {
1825                                 if input.previous_output.txid == current_local_signed_commitment_tx.txid {
1826                                         scan_commitment!(current_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a),
1827                                                 current_local_signed_commitment_tx.htlc_sources,
1828                                                 "our latest local commitment tx");
1829                                 }
1830                         }
1831                         if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
1832                                 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
1833                                         scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a),
1834                                                 prev_local_signed_commitment_tx.htlc_sources,
1835                                                 "our latest local commitment tx");
1836                                 }
1837                         }
1838                         if let Some(&(ref htlc_outputs, ref htlc_sources)) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
1839                                 scan_commitment!(htlc_outputs, htlc_sources, "remote commitment tx");
1840                         }
1841
1842                         // If tx isn't solving htlc output from local/remote commitment tx and htlc isn't outbound we don't need
1843                         // to broadcast solving backward
1844                         if let Some((source, payment_hash)) = payment_data {
1845                                 let mut payment_preimage = PaymentPreimage([0; 32]);
1846                                 if (input.witness.len() == 3 && input.witness[2].len() == OFFERED_HTLC_SCRIPT_WEIGHT && input.witness[1].len() == 33)
1847                                         || (input.witness.len() == 3 && input.witness[2].len() == ACCEPTED_HTLC_SCRIPT_WEIGHT && input.witness[1].len() == 33) {
1848                                         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);
1849                                 } else if input.witness.len() == 5 && input.witness[4].len() == ACCEPTED_HTLC_SCRIPT_WEIGHT {
1850                                         payment_preimage.0.copy_from_slice(&tx.input[0].witness[3]);
1851                                         htlc_updated.push((source, Some(payment_preimage), payment_hash));
1852                                 } else if input.witness.len() == 3 && input.witness[2].len() == OFFERED_HTLC_SCRIPT_WEIGHT {
1853                                         payment_preimage.0.copy_from_slice(&tx.input[0].witness[1]);
1854                                         htlc_updated.push((source, Some(payment_preimage), payment_hash));
1855                                 } else {
1856                                         htlc_updated.push((source, None, payment_hash));
1857                                 }
1858                         }
1859                 }
1860                 htlc_updated
1861         }
1862 }
1863
1864 const MAX_ALLOC_SIZE: usize = 64*1024;
1865
1866 impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
1867         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
1868                 let secp_ctx = Secp256k1::new();
1869                 macro_rules! unwrap_obj {
1870                         ($key: expr) => {
1871                                 match $key {
1872                                         Ok(res) => res,
1873                                         Err(_) => return Err(DecodeError::InvalidValue),
1874                                 }
1875                         }
1876                 }
1877
1878                 let _ver: u8 = Readable::read(reader)?;
1879                 let min_ver: u8 = Readable::read(reader)?;
1880                 if min_ver > SERIALIZATION_VERSION {
1881                         return Err(DecodeError::UnknownVersion);
1882                 }
1883
1884                 let commitment_transaction_number_obscure_factor = <U48 as Readable<R>>::read(reader)?.0;
1885
1886                 let key_storage = match <u8 as Readable<R>>::read(reader)? {
1887                         0 => {
1888                                 let revocation_base_key = Readable::read(reader)?;
1889                                 let htlc_base_key = Readable::read(reader)?;
1890                                 let delayed_payment_base_key = Readable::read(reader)?;
1891                                 let payment_base_key = Readable::read(reader)?;
1892                                 let shutdown_pubkey = Readable::read(reader)?;
1893                                 let prev_latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1894                                         0 => None,
1895                                         1 => Some(Readable::read(reader)?),
1896                                         _ => return Err(DecodeError::InvalidValue),
1897                                 };
1898                                 let latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1899                                         0 => None,
1900                                         1 => Some(Readable::read(reader)?),
1901                                         _ => return Err(DecodeError::InvalidValue),
1902                                 };
1903                                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1904                                 // barely-init'd ChannelMonitors that we can't do anything with.
1905                                 let outpoint = OutPoint {
1906                                         txid: Readable::read(reader)?,
1907                                         index: Readable::read(reader)?,
1908                                 };
1909                                 let funding_info = Some((outpoint, Readable::read(reader)?));
1910                                 let current_remote_commitment_txid = match <u8 as Readable<R>>::read(reader)? {
1911                                         0 => None,
1912                                         1 => Some(Readable::read(reader)?),
1913                                         _ => return Err(DecodeError::InvalidValue),
1914                                 };
1915                                 let prev_remote_commitment_txid = match <u8 as Readable<R>>::read(reader)? {
1916                                         0 => None,
1917                                         1 => Some(Readable::read(reader)?),
1918                                         _ => return Err(DecodeError::InvalidValue),
1919                                 };
1920                                 Storage::Local {
1921                                         revocation_base_key,
1922                                         htlc_base_key,
1923                                         delayed_payment_base_key,
1924                                         payment_base_key,
1925                                         shutdown_pubkey,
1926                                         prev_latest_per_commitment_point,
1927                                         latest_per_commitment_point,
1928                                         funding_info,
1929                                         current_remote_commitment_txid,
1930                                         prev_remote_commitment_txid,
1931                                 }
1932                         },
1933                         _ => return Err(DecodeError::InvalidValue),
1934                 };
1935
1936                 let their_htlc_base_key = Some(Readable::read(reader)?);
1937                 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
1938
1939                 let their_cur_revocation_points = {
1940                         let first_idx = <U48 as Readable<R>>::read(reader)?.0;
1941                         if first_idx == 0 {
1942                                 None
1943                         } else {
1944                                 let first_point = Readable::read(reader)?;
1945                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
1946                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1947                                         Some((first_idx, first_point, None))
1948                                 } else {
1949                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, &second_point_slice)))))
1950                                 }
1951                         }
1952                 };
1953
1954                 let our_to_self_delay: u16 = Readable::read(reader)?;
1955                 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
1956
1957                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1958                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1959                         *secret = Readable::read(reader)?;
1960                         *idx = Readable::read(reader)?;
1961                 }
1962
1963                 macro_rules! read_htlc_in_commitment {
1964                         () => {
1965                                 {
1966                                         let offered: bool = Readable::read(reader)?;
1967                                         let amount_msat: u64 = Readable::read(reader)?;
1968                                         let cltv_expiry: u32 = Readable::read(reader)?;
1969                                         let payment_hash: PaymentHash = Readable::read(reader)?;
1970                                         let transaction_output_index: u32 = Readable::read(reader)?;
1971
1972                                         HTLCOutputInCommitment {
1973                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1974                                         }
1975                                 }
1976                         }
1977                 }
1978
1979                 macro_rules! read_htlc_source {
1980                         () => {
1981                                 {
1982                                         (Readable::read(reader)?, Readable::read(reader)?,
1983                                                 match <u8 as Readable<R>>::read(reader)? {
1984                                                         0 => None,
1985                                                         1 => Some(Readable::read(reader)?),
1986                                                         _ => return Err(DecodeError::InvalidValue),
1987                                                 }
1988                                         )
1989                                 }
1990                         }
1991                 }
1992
1993                 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
1994                 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
1995                 for _ in 0..remote_claimable_outpoints_len {
1996                         let txid: Sha256dHash = Readable::read(reader)?;
1997                         let outputs_count: u64 = Readable::read(reader)?;
1998                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 32));
1999                         for _ in 0..outputs_count {
2000                                 outputs.push(read_htlc_in_commitment!());
2001                         }
2002                         let sources_count: u64 = Readable::read(reader)?;
2003                         let mut sources = Vec::with_capacity(cmp::min(sources_count as usize, MAX_ALLOC_SIZE / 32));
2004                         for _ in 0..sources_count {
2005                                 sources.push(read_htlc_source!());
2006                         }
2007                         if let Some(_) = remote_claimable_outpoints.insert(txid, (outputs, sources)) {
2008                                 return Err(DecodeError::InvalidValue);
2009                         }
2010                 }
2011
2012                 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2013                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2014                 for _ in 0..remote_commitment_txn_on_chain_len {
2015                         let txid: Sha256dHash = Readable::read(reader)?;
2016                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
2017                         let outputs_count = <u64 as Readable<R>>::read(reader)?;
2018                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2019                         for _ in 0..outputs_count {
2020                                 outputs.push(Readable::read(reader)?);
2021                         }
2022                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2023                                 return Err(DecodeError::InvalidValue);
2024                         }
2025                 }
2026
2027                 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2028                 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2029                 for _ in 0..remote_hash_commitment_number_len {
2030                         let payment_hash: PaymentHash = Readable::read(reader)?;
2031                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
2032                         if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2033                                 return Err(DecodeError::InvalidValue);
2034                         }
2035                 }
2036
2037                 macro_rules! read_local_tx {
2038                         () => {
2039                                 {
2040                                         let tx = match Transaction::consensus_decode(reader.by_ref()) {
2041                                                 Ok(tx) => tx,
2042                                                 Err(e) => match e {
2043                                                         encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)),
2044                                                         _ => return Err(DecodeError::InvalidValue),
2045                                                 },
2046                                         };
2047
2048                                         if tx.input.is_empty() {
2049                                                 // Ensure tx didn't hit the 0-input ambiguity case.
2050                                                 return Err(DecodeError::InvalidValue);
2051                                         }
2052
2053                                         let revocation_key = Readable::read(reader)?;
2054                                         let a_htlc_key = Readable::read(reader)?;
2055                                         let b_htlc_key = Readable::read(reader)?;
2056                                         let delayed_payment_key = Readable::read(reader)?;
2057                                         let feerate_per_kw: u64 = Readable::read(reader)?;
2058
2059                                         let htlc_outputs_len: u64 = Readable::read(reader)?;
2060                                         let mut htlc_outputs = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
2061                                         for _ in 0..htlc_outputs_len {
2062                                                 let out = read_htlc_in_commitment!();
2063                                                 let sigs = (Readable::read(reader)?, Readable::read(reader)?);
2064                                                 htlc_outputs.push((out, sigs.0, sigs.1));
2065                                         }
2066
2067                                         let htlc_sources_len: u64 = Readable::read(reader)?;
2068                                         let mut htlc_sources = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
2069                                         for _ in 0..htlc_sources_len {
2070                                                 htlc_sources.push(read_htlc_source!());
2071                                         }
2072
2073                                         LocalSignedTx {
2074                                                 txid: tx.txid(),
2075                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs, htlc_sources
2076                                         }
2077                                 }
2078                         }
2079                 }
2080
2081                 let prev_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
2082                         0 => None,
2083                         1 => {
2084                                 Some(read_local_tx!())
2085                         },
2086                         _ => return Err(DecodeError::InvalidValue),
2087                 };
2088
2089                 let current_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
2090                         0 => None,
2091                         1 => {
2092                                 Some(read_local_tx!())
2093                         },
2094                         _ => return Err(DecodeError::InvalidValue),
2095                 };
2096
2097                 let current_remote_commitment_number = <U48 as Readable<R>>::read(reader)?.0;
2098
2099                 let payment_preimages_len: u64 = Readable::read(reader)?;
2100                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2101                 let mut sha = Sha256::new();
2102                 for _ in 0..payment_preimages_len {
2103                         let preimage: PaymentPreimage = Readable::read(reader)?;
2104                         sha.reset();
2105                         sha.input(&preimage.0[..]);
2106                         let mut hash = PaymentHash([0; 32]);
2107                         sha.result(&mut hash.0[..]);
2108                         if let Some(_) = payment_preimages.insert(hash, preimage) {
2109                                 return Err(DecodeError::InvalidValue);
2110                         }
2111                 }
2112
2113                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
2114                 let destination_script = Readable::read(reader)?;
2115
2116                 Ok((last_block_hash.clone(), ChannelMonitor {
2117                         commitment_transaction_number_obscure_factor,
2118
2119                         key_storage,
2120                         their_htlc_base_key,
2121                         their_delayed_payment_base_key,
2122                         their_cur_revocation_points,
2123
2124                         our_to_self_delay,
2125                         their_to_self_delay,
2126
2127                         old_secrets,
2128                         remote_claimable_outpoints,
2129                         remote_commitment_txn_on_chain,
2130                         remote_hash_commitment_number,
2131
2132                         prev_local_signed_commitment_tx,
2133                         current_local_signed_commitment_tx,
2134                         current_remote_commitment_number,
2135
2136                         payment_preimages,
2137
2138                         destination_script,
2139                         last_block_hash,
2140                         secp_ctx,
2141                         logger,
2142                 }))
2143         }
2144
2145 }
2146
2147 #[cfg(test)]
2148 mod tests {
2149         use bitcoin::blockdata::script::Script;
2150         use bitcoin::blockdata::transaction::Transaction;
2151         use crypto::digest::Digest;
2152         use hex;
2153         use ln::channelmanager::{PaymentPreimage, PaymentHash};
2154         use ln::channelmonitor::ChannelMonitor;
2155         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
2156         use util::sha2::Sha256;
2157         use util::test_utils::TestLogger;
2158         use secp256k1::key::{SecretKey,PublicKey};
2159         use secp256k1::{Secp256k1, Signature};
2160         use rand::{thread_rng,Rng};
2161         use std::sync::Arc;
2162
2163         #[test]
2164         fn test_per_commitment_storage() {
2165                 // Test vectors from BOLT 3:
2166                 let mut secrets: Vec<[u8; 32]> = Vec::new();
2167                 let mut monitor: ChannelMonitor;
2168                 let secp_ctx = Secp256k1::new();
2169                 let logger = Arc::new(TestLogger::new());
2170
2171                 macro_rules! test_secrets {
2172                         () => {
2173                                 let mut idx = 281474976710655;
2174                                 for secret in secrets.iter() {
2175                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
2176                                         idx -= 1;
2177                                 }
2178                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
2179                                 assert!(monitor.get_secret(idx).is_none());
2180                         };
2181                 }
2182
2183                 {
2184                         // insert_secret correct sequence
2185                         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());
2186                         secrets.clear();
2187
2188                         secrets.push([0; 32]);
2189                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2190                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2191                         test_secrets!();
2192
2193                         secrets.push([0; 32]);
2194                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2195                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2196                         test_secrets!();
2197
2198                         secrets.push([0; 32]);
2199                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2200                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2201                         test_secrets!();
2202
2203                         secrets.push([0; 32]);
2204                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2205                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2206                         test_secrets!();
2207
2208                         secrets.push([0; 32]);
2209                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2210                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2211                         test_secrets!();
2212
2213                         secrets.push([0; 32]);
2214                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2215                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2216                         test_secrets!();
2217
2218                         secrets.push([0; 32]);
2219                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2220                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2221                         test_secrets!();
2222
2223                         secrets.push([0; 32]);
2224                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2225                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
2226                         test_secrets!();
2227                 }
2228
2229                 {
2230                         // insert_secret #1 incorrect
2231                         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());
2232                         secrets.clear();
2233
2234                         secrets.push([0; 32]);
2235                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2236                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2237                         test_secrets!();
2238
2239                         secrets.push([0; 32]);
2240                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2241                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().0,
2242                                         "Previous secret did not match new one");
2243                 }
2244
2245                 {
2246                         // insert_secret #2 incorrect (#1 derived from incorrect)
2247                         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());
2248                         secrets.clear();
2249
2250                         secrets.push([0; 32]);
2251                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2252                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2253                         test_secrets!();
2254
2255                         secrets.push([0; 32]);
2256                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2257                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2258                         test_secrets!();
2259
2260                         secrets.push([0; 32]);
2261                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2262                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2263                         test_secrets!();
2264
2265                         secrets.push([0; 32]);
2266                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2267                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
2268                                         "Previous secret did not match new one");
2269                 }
2270
2271                 {
2272                         // insert_secret #3 incorrect
2273                         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());
2274                         secrets.clear();
2275
2276                         secrets.push([0; 32]);
2277                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2278                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2279                         test_secrets!();
2280
2281                         secrets.push([0; 32]);
2282                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2283                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2284                         test_secrets!();
2285
2286                         secrets.push([0; 32]);
2287                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2288                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2289                         test_secrets!();
2290
2291                         secrets.push([0; 32]);
2292                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2293                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
2294                                         "Previous secret did not match new one");
2295                 }
2296
2297                 {
2298                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
2299                         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());
2300                         secrets.clear();
2301
2302                         secrets.push([0; 32]);
2303                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2304                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2305                         test_secrets!();
2306
2307                         secrets.push([0; 32]);
2308                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2309                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2310                         test_secrets!();
2311
2312                         secrets.push([0; 32]);
2313                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2314                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2315                         test_secrets!();
2316
2317                         secrets.push([0; 32]);
2318                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
2319                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2320                         test_secrets!();
2321
2322                         secrets.push([0; 32]);
2323                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2324                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2325                         test_secrets!();
2326
2327                         secrets.push([0; 32]);
2328                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2329                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2330                         test_secrets!();
2331
2332                         secrets.push([0; 32]);
2333                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2334                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2335                         test_secrets!();
2336
2337                         secrets.push([0; 32]);
2338                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2339                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2340                                         "Previous secret did not match new one");
2341                 }
2342
2343                 {
2344                         // insert_secret #5 incorrect
2345                         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());
2346                         secrets.clear();
2347
2348                         secrets.push([0; 32]);
2349                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2350                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2351                         test_secrets!();
2352
2353                         secrets.push([0; 32]);
2354                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2355                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2356                         test_secrets!();
2357
2358                         secrets.push([0; 32]);
2359                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2360                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2361                         test_secrets!();
2362
2363                         secrets.push([0; 32]);
2364                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2365                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2366                         test_secrets!();
2367
2368                         secrets.push([0; 32]);
2369                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2370                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2371                         test_secrets!();
2372
2373                         secrets.push([0; 32]);
2374                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2375                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().0,
2376                                         "Previous secret did not match new one");
2377                 }
2378
2379                 {
2380                         // insert_secret #6 incorrect (5 derived from incorrect)
2381                         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());
2382                         secrets.clear();
2383
2384                         secrets.push([0; 32]);
2385                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2386                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2387                         test_secrets!();
2388
2389                         secrets.push([0; 32]);
2390                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2391                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2392                         test_secrets!();
2393
2394                         secrets.push([0; 32]);
2395                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2396                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2397                         test_secrets!();
2398
2399                         secrets.push([0; 32]);
2400                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2401                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2402                         test_secrets!();
2403
2404                         secrets.push([0; 32]);
2405                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2406                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2407                         test_secrets!();
2408
2409                         secrets.push([0; 32]);
2410                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2411                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2412                         test_secrets!();
2413
2414                         secrets.push([0; 32]);
2415                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2416                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2417                         test_secrets!();
2418
2419                         secrets.push([0; 32]);
2420                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2421                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2422                                         "Previous secret did not match new one");
2423                 }
2424
2425                 {
2426                         // insert_secret #7 incorrect
2427                         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());
2428                         secrets.clear();
2429
2430                         secrets.push([0; 32]);
2431                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2432                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2433                         test_secrets!();
2434
2435                         secrets.push([0; 32]);
2436                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2437                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2438                         test_secrets!();
2439
2440                         secrets.push([0; 32]);
2441                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2442                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2443                         test_secrets!();
2444
2445                         secrets.push([0; 32]);
2446                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2447                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2448                         test_secrets!();
2449
2450                         secrets.push([0; 32]);
2451                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2452                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2453                         test_secrets!();
2454
2455                         secrets.push([0; 32]);
2456                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2457                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2458                         test_secrets!();
2459
2460                         secrets.push([0; 32]);
2461                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2462                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2463                         test_secrets!();
2464
2465                         secrets.push([0; 32]);
2466                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2467                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2468                                         "Previous secret did not match new one");
2469                 }
2470
2471                 {
2472                         // insert_secret #8 incorrect
2473                         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());
2474                         secrets.clear();
2475
2476                         secrets.push([0; 32]);
2477                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2478                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2479                         test_secrets!();
2480
2481                         secrets.push([0; 32]);
2482                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2483                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2484                         test_secrets!();
2485
2486                         secrets.push([0; 32]);
2487                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2488                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2489                         test_secrets!();
2490
2491                         secrets.push([0; 32]);
2492                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2493                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2494                         test_secrets!();
2495
2496                         secrets.push([0; 32]);
2497                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2498                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2499                         test_secrets!();
2500
2501                         secrets.push([0; 32]);
2502                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2503                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2504                         test_secrets!();
2505
2506                         secrets.push([0; 32]);
2507                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2508                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2509                         test_secrets!();
2510
2511                         secrets.push([0; 32]);
2512                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2513                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2514                                         "Previous secret did not match new one");
2515                 }
2516         }
2517
2518         #[test]
2519         fn test_prune_preimages() {
2520                 let secp_ctx = Secp256k1::new();
2521                 let logger = Arc::new(TestLogger::new());
2522                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
2523
2524                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
2525                 macro_rules! dummy_keys {
2526                         () => {
2527                                 {
2528                                         TxCreationKeys {
2529                                                 per_commitment_point: dummy_key.clone(),
2530                                                 revocation_key: dummy_key.clone(),
2531                                                 a_htlc_key: dummy_key.clone(),
2532                                                 b_htlc_key: dummy_key.clone(),
2533                                                 a_delayed_payment_key: dummy_key.clone(),
2534                                                 b_payment_key: dummy_key.clone(),
2535                                         }
2536                                 }
2537                         }
2538                 }
2539                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2540
2541                 let mut preimages = Vec::new();
2542                 {
2543                         let mut rng  = thread_rng();
2544                         for _ in 0..20 {
2545                                 let mut preimage = PaymentPreimage([0; 32]);
2546                                 rng.fill_bytes(&mut preimage.0[..]);
2547                                 let mut sha = Sha256::new();
2548                                 sha.input(&preimage.0[..]);
2549                                 let mut hash = PaymentHash([0; 32]);
2550                                 sha.result(&mut hash.0[..]);
2551                                 preimages.push((preimage, hash));
2552                         }
2553                 }
2554
2555                 macro_rules! preimages_slice_to_htlc_outputs {
2556                         ($preimages_slice: expr) => {
2557                                 {
2558                                         let mut res = Vec::new();
2559                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
2560                                                 res.push(HTLCOutputInCommitment {
2561                                                         offered: true,
2562                                                         amount_msat: 0,
2563                                                         cltv_expiry: 0,
2564                                                         payment_hash: preimage.1.clone(),
2565                                                         transaction_output_index: idx as u32,
2566                                                 });
2567                                         }
2568                                         res
2569                                 }
2570                         }
2571                 }
2572                 macro_rules! preimages_to_local_htlcs {
2573                         ($preimages_slice: expr) => {
2574                                 {
2575                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2576                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
2577                                         res
2578                                 }
2579                         }
2580                 }
2581
2582                 macro_rules! test_preimages_exist {
2583                         ($preimages_slice: expr, $monitor: expr) => {
2584                                 for preimage in $preimages_slice {
2585                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
2586                                 }
2587                         }
2588                 }
2589
2590                 // Prune with one old state and a local commitment tx holding a few overlaps with the
2591                 // old state.
2592                 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());
2593                 monitor.set_their_to_self_delay(10);
2594
2595                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]), Vec::new());
2596                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), Vec::new(), 281474976710655, dummy_key);
2597                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), Vec::new(), 281474976710654, dummy_key);
2598                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), Vec::new(), 281474976710653, dummy_key);
2599                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), Vec::new(), 281474976710652, dummy_key);
2600                 for &(ref preimage, ref hash) in preimages.iter() {
2601                         monitor.provide_payment_preimage(hash, preimage);
2602                 }
2603
2604                 // Now provide a secret, pruning preimages 10-15
2605                 let mut secret = [0; 32];
2606                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2607                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2608                 assert_eq!(monitor.payment_preimages.len(), 15);
2609                 test_preimages_exist!(&preimages[0..10], monitor);
2610                 test_preimages_exist!(&preimages[15..20], monitor);
2611
2612                 // Now provide a further secret, pruning preimages 15-17
2613                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2614                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2615                 assert_eq!(monitor.payment_preimages.len(), 13);
2616                 test_preimages_exist!(&preimages[0..10], monitor);
2617                 test_preimages_exist!(&preimages[17..20], monitor);
2618
2619                 // Now update local commitment tx info, pruning only element 18 as we still care about the
2620                 // previous commitment tx's preimages too
2621                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]), Vec::new());
2622                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2623                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2624                 assert_eq!(monitor.payment_preimages.len(), 12);
2625                 test_preimages_exist!(&preimages[0..10], monitor);
2626                 test_preimages_exist!(&preimages[18..20], monitor);
2627
2628                 // But if we do it again, we'll prune 5-10
2629                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]), Vec::new());
2630                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2631                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2632                 assert_eq!(monitor.payment_preimages.len(), 5);
2633                 test_preimages_exist!(&preimages[0..5], monitor);
2634         }
2635
2636         // Further testing is done in the ChannelManager integration tests.
2637 }