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

   1 //! The logic to build claims and bump in-flight transactions until confirmations.
   2 //!
   3 //! OnchainTxHandler objetcs are fully-part of ChannelMonitor and encapsulates all
   4 //! building, tracking, bumping and notifications functions.
   5
   6 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
   7 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
   8 use bitcoin::blockdata::script::Script;
   9 use bitcoin::util::bip143;
  10
  11 use bitcoin::hash_types::Txid;
  12
  13 use bitcoin::secp256k1::{Secp256k1, Signature};
  14 use bitcoin::secp256k1;
  15
  16 use ln::msgs::DecodeError;
  17 use ln::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER, InputMaterial, ClaimRequest};
  18 use ln::channelmanager::PaymentPreimage;
  19 use ln::chan_utils::{HTLCType, LocalCommitmentTransaction};
  20 use chain::chaininterface::{FeeEstimator, BroadcasterInterface, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
  21 use chain::keysinterface::ChannelKeys;
  22 use util::logger::Logger;
  23 use util::ser::{Readable, Writer, Writeable};
  24 use util::byte_utils;
  25
  26 use std::collections::{HashMap, hash_map};
  27 use std::cmp;
  28 use std::ops::Deref;
  29
  30 const MAX_ALLOC_SIZE: usize = 64*1024;
  31
  32 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
  33 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
  34 #[derive(Clone, PartialEq)]
  35 enum OnchainEvent {
  36         /// Outpoint under claim process by our own tx, once this one get enough confirmations, we remove it from
  37         /// bump-txn candidate buffer.
  38         Claim {
  39                 claim_request: Txid,
  40         },
  41         /// Claim tx aggregate multiple claimable outpoints. One of the outpoint may be claimed by a remote party tx.
  42         /// In this case, we need to drop the outpoint and regenerate a new claim tx. By safety, we keep tracking
  43         /// the outpoint to be sure to resurect it back to the claim tx if reorgs happen.
  44         ContentiousOutpoint {
  45                 outpoint: BitcoinOutPoint,
  46                 input_material: InputMaterial,
  47         }
  48 }
  49
  50 /// Higher-level cache structure needed to re-generate bumped claim txn if needed
  51 #[derive(Clone, PartialEq)]
  52 pub struct ClaimTxBumpMaterial {
  53         // At every block tick, used to check if pending claiming tx is taking too
  54         // much time for confirmation and we need to bump it.
  55         height_timer: Option<u32>,
  56         // Tracked in case of reorg to wipe out now-superflous bump material
  57         feerate_previous: u64,
  58         // Soonest timelocks among set of outpoints claimed, used to compute
  59         // a priority of not feerate
  60         soonest_timelock: u32,
  61         // Cache of script, pubkey, sig or key to solve claimable outputs scriptpubkey.
  62         per_input_material: HashMap<BitcoinOutPoint, InputMaterial>,
  63 }
  64
  65 impl Writeable for ClaimTxBumpMaterial  {
  66         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
  67                 self.height_timer.write(writer)?;
  68                 writer.write_all(&byte_utils::be64_to_array(self.feerate_previous))?;
  69                 writer.write_all(&byte_utils::be32_to_array(self.soonest_timelock))?;
  70                 writer.write_all(&byte_utils::be64_to_array(self.per_input_material.len() as u64))?;
  71                 for (outp, tx_material) in self.per_input_material.iter() {
  72                         outp.write(writer)?;
  73                         tx_material.write(writer)?;
  74                 }
  75                 Ok(())
  76         }
  77 }
  78
  79 impl Readable for ClaimTxBumpMaterial {
  80         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
  81                 let height_timer = Readable::read(reader)?;
  82                 let feerate_previous = Readable::read(reader)?;
  83                 let soonest_timelock = Readable::read(reader)?;
  84                 let per_input_material_len: u64 = Readable::read(reader)?;
  85                 let mut per_input_material = HashMap::with_capacity(cmp::min(per_input_material_len as usize, MAX_ALLOC_SIZE / 128));
  86                 for _ in 0 ..per_input_material_len {
  87                         let outpoint = Readable::read(reader)?;
  88                         let input_material = Readable::read(reader)?;
  89                         per_input_material.insert(outpoint, input_material);
  90                 }
  91                 Ok(Self { height_timer, feerate_previous, soonest_timelock, per_input_material })
  92         }
  93 }
  94
  95 #[derive(PartialEq)]
  96 pub(super) enum InputDescriptors {
  97         RevokedOfferedHTLC,
  98         RevokedReceivedHTLC,
  99         OfferedHTLC,
 100         ReceivedHTLC,
 101         RevokedOutput, // either a revoked to_local output on commitment tx, a revoked HTLC-Timeout output or a revoked HTLC-Success output
 102 }
 103
 104 macro_rules! subtract_high_prio_fee {
 105         ($logger: ident, $fee_estimator: expr, $value: expr, $predicted_weight: expr, $used_feerate: expr) => {
 106                 {
 107                         $used_feerate = $fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority);
 108                         let mut fee = $used_feerate * ($predicted_weight as u64) / 1000;
 109                         if $value <= fee {
 110                                 $used_feerate = $fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 111                                 fee = $used_feerate * ($predicted_weight as u64) / 1000;
 112                                 if $value <= fee {
 113                                         $used_feerate = $fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 114                                         fee = $used_feerate * ($predicted_weight as u64) / 1000;
 115                                         if $value <= fee {
 116                                                 log_error!($logger, "Failed to generate an on-chain punishment tx as even low priority fee ({} sat) was more than the entire claim balance ({} sat)",
 117                                                         fee, $value);
 118                                                 false
 119                                         } else {
 120                                                 log_warn!($logger, "Used low priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
 121                                                         $value);
 122                                                 $value -= fee;
 123                                                 true
 124                                         }
 125                                 } else {
 126                                         log_warn!($logger, "Used medium priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
 127                                                 $value);
 128                                         $value -= fee;
 129                                         true
 130                                 }
 131                         } else {
 132                                 $value -= fee;
 133                                 true
 134                         }
 135                 }
 136         }
 137 }
 138
 139 impl Readable for Option<Vec<Option<(usize, Signature)>>> {
 140         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 141                 match Readable::read(reader)? {
 142                         0u8 => Ok(None),
 143                         1u8 => {
 144                                 let vlen: u64 = Readable::read(reader)?;
 145                                 let mut ret = Vec::with_capacity(cmp::min(vlen as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<Option<(usize, Signature)>>()));
 146                                 for _ in 0..vlen {
 147                                         ret.push(match Readable::read(reader)? {
 148                                                 0u8 => None,
 149                                                 1u8 => Some((<u64 as Readable>::read(reader)? as usize, Readable::read(reader)?)),
 150                                                 _ => return Err(DecodeError::InvalidValue)
 151                                         });
 152                                 }
 153                                 Ok(Some(ret))
 154                         },
 155                         _ => Err(DecodeError::InvalidValue),
 156                 }
 157         }
 158 }
 159
 160 impl Writeable for Option<Vec<Option<(usize, Signature)>>> {
 161         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 162                 match self {
 163                         &Some(ref vec) => {
 164                                 1u8.write(writer)?;
 165                                 (vec.len() as u64).write(writer)?;
 166                                 for opt in vec.iter() {
 167                                         match opt {
 168                                                 &Some((ref idx, ref sig)) => {
 169                                                         1u8.write(writer)?;
 170                                                         (*idx as u64).write(writer)?;
 171                                                         sig.write(writer)?;
 172                                                 },
 173                                                 &None => 0u8.write(writer)?,
 174                                         }
 175                                 }
 176                         },
 177                         &None => 0u8.write(writer)?,
 178                 }
 179                 Ok(())
 180         }
 181 }
 182
 183
 184 /// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
 185 /// do RBF bumping if possible.
 186 pub struct OnchainTxHandler<ChanSigner: ChannelKeys> {
 187         destination_script: Script,
 188         local_commitment: Option<LocalCommitmentTransaction>,
 189         // local_htlc_sigs and prev_local_htlc_sigs are in the order as they appear in the commitment
 190         // transaction outputs (hence the Option<>s inside the Vec). The first usize is the index in
 191         // the set of HTLCs in the LocalCommitmentTransaction (including those which do not appear in
 192         // the commitment transaction).
 193         local_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
 194         prev_local_commitment: Option<LocalCommitmentTransaction>,
 195         prev_local_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
 196         local_csv: u16,
 197
 198         key_storage: ChanSigner,
 199
 200         // Used to track claiming requests. If claim tx doesn't confirm before height timer expiration we need to bump
 201         // it (RBF or CPFP). If an input has been part of an aggregate tx at first claim try, we need to keep it within
 202         // another bumped aggregate tx to comply with RBF rules. We may have multiple claiming txn in the flight for the
 203         // same set of outpoints. One of the outpoints may be spent by a transaction not issued by us. That's why at
 204         // block connection we scan all inputs and if any of them is among a set of a claiming request we test for set
 205         // equality between spending transaction and claim request. If true, it means transaction was one our claiming one
 206         // after a security delay of 6 blocks we remove pending claim request. If false, it means transaction wasn't and
 207         // we need to regenerate new claim request with reduced set of still-claimable outpoints.
 208         // Key is identifier of the pending claim request, i.e the txid of the initial claiming transaction generated by
 209         // us and is immutable until all outpoint of the claimable set are post-anti-reorg-delay solved.
 210         // Entry is cache of elements need to generate a bumped claiming transaction (see ClaimTxBumpMaterial)
 211         #[cfg(test)] // Used in functional_test to verify sanitization
 212         pub pending_claim_requests: HashMap<Txid, ClaimTxBumpMaterial>,
 213         #[cfg(not(test))]
 214         pending_claim_requests: HashMap<Txid, ClaimTxBumpMaterial>,
 215
 216         // Used to link outpoints claimed in a connected block to a pending claim request.
 217         // Key is outpoint than monitor parsing has detected we have keys/scripts to claim
 218         // Value is (pending claim request identifier, confirmation_block), identifier
 219         // is txid of the initial claiming transaction and is immutable until outpoint is
 220         // post-anti-reorg-delay solved, confirmaiton_block is used to erase entry if
 221         // block with output gets disconnected.
 222         #[cfg(test)] // Used in functional_test to verify sanitization
 223         pub claimable_outpoints: HashMap<BitcoinOutPoint, (Txid, u32)>,
 224         #[cfg(not(test))]
 225         claimable_outpoints: HashMap<BitcoinOutPoint, (Txid, u32)>,
 226
 227         onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
 228
 229         secp_ctx: Secp256k1<secp256k1::All>,
 230 }
 231
 232 impl<ChanSigner: ChannelKeys + Writeable> OnchainTxHandler<ChanSigner> {
 233         pub(crate) fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 234                 self.destination_script.write(writer)?;
 235                 self.local_commitment.write(writer)?;
 236                 self.local_htlc_sigs.write(writer)?;
 237                 self.prev_local_commitment.write(writer)?;
 238                 self.prev_local_htlc_sigs.write(writer)?;
 239
 240                 self.local_csv.write(writer)?;
 241
 242                 self.key_storage.write(writer)?;
 243
 244                 writer.write_all(&byte_utils::be64_to_array(self.pending_claim_requests.len() as u64))?;
 245                 for (ref ancestor_claim_txid, claim_tx_data) in self.pending_claim_requests.iter() {
 246                         ancestor_claim_txid.write(writer)?;
 247                         claim_tx_data.write(writer)?;
 248                 }
 249
 250                 writer.write_all(&byte_utils::be64_to_array(self.claimable_outpoints.len() as u64))?;
 251                 for (ref outp, ref claim_and_height) in self.claimable_outpoints.iter() {
 252                         outp.write(writer)?;
 253                         claim_and_height.0.write(writer)?;
 254                         claim_and_height.1.write(writer)?;
 255                 }
 256
 257                 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
 258                 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
 259                         writer.write_all(&byte_utils::be32_to_array(**target))?;
 260                         writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
 261                         for ev in events.iter() {
 262                                 match *ev {
 263                                         OnchainEvent::Claim { ref claim_request } => {
 264                                                 writer.write_all(&[0; 1])?;
 265                                                 claim_request.write(writer)?;
 266                                         },
 267                                         OnchainEvent::ContentiousOutpoint { ref outpoint, ref input_material } => {
 268                                                 writer.write_all(&[1; 1])?;
 269                                                 outpoint.write(writer)?;
 270                                                 input_material.write(writer)?;
 271                                         }
 272                                 }
 273                         }
 274                 }
 275                 Ok(())
 276         }
 277 }
 278
 279 impl<ChanSigner: ChannelKeys + Readable> Readable for OnchainTxHandler<ChanSigner> {
 280         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 281                 let destination_script = Readable::read(reader)?;
 282
 283                 let local_commitment = Readable::read(reader)?;
 284                 let local_htlc_sigs = Readable::read(reader)?;
 285                 let prev_local_commitment = Readable::read(reader)?;
 286                 let prev_local_htlc_sigs = Readable::read(reader)?;
 287
 288                 let local_csv = Readable::read(reader)?;
 289
 290                 let key_storage = Readable::read(reader)?;
 291
 292                 let pending_claim_requests_len: u64 = Readable::read(reader)?;
 293                 let mut pending_claim_requests = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
 294                 for _ in 0..pending_claim_requests_len {
 295                         pending_claim_requests.insert(Readable::read(reader)?, Readable::read(reader)?);
 296                 }
 297
 298                 let claimable_outpoints_len: u64 = Readable::read(reader)?;
 299                 let mut claimable_outpoints = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
 300                 for _ in 0..claimable_outpoints_len {
 301                         let outpoint = Readable::read(reader)?;
 302                         let ancestor_claim_txid = Readable::read(reader)?;
 303                         let height = Readable::read(reader)?;
 304                         claimable_outpoints.insert(outpoint, (ancestor_claim_txid, height));
 305                 }
 306                 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
 307                 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
 308                 for _ in 0..waiting_threshold_conf_len {
 309                         let height_target = Readable::read(reader)?;
 310                         let events_len: u64 = Readable::read(reader)?;
 311                         let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
 312                         for _ in 0..events_len {
 313                                 let ev = match <u8 as Readable>::read(reader)? {
 314                                         0 => {
 315                                                 let claim_request = Readable::read(reader)?;
 316                                                 OnchainEvent::Claim {
 317                                                         claim_request
 318                                                 }
 319                                         },
 320                                         1 => {
 321                                                 let outpoint = Readable::read(reader)?;
 322                                                 let input_material = Readable::read(reader)?;
 323                                                 OnchainEvent::ContentiousOutpoint {
 324                                                         outpoint,
 325                                                         input_material
 326                                                 }
 327                                         }
 328                                         _ => return Err(DecodeError::InvalidValue),
 329                                 };
 330                                 events.push(ev);
 331                         }
 332                         onchain_events_waiting_threshold_conf.insert(height_target, events);
 333                 }
 334
 335                 Ok(OnchainTxHandler {
 336                         destination_script,
 337                         local_commitment,
 338                         local_htlc_sigs,
 339                         prev_local_commitment,
 340                         prev_local_htlc_sigs,
 341                         local_csv,
 342                         key_storage,
 343                         claimable_outpoints,
 344                         pending_claim_requests,
 345                         onchain_events_waiting_threshold_conf,
 346                         secp_ctx: Secp256k1::new(),
 347                 })
 348         }
 349 }
 350
 351 impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
 352         pub(super) fn new(destination_script: Script, keys: ChanSigner, local_csv: u16) -> Self {
 353
 354                 let key_storage = keys;
 355
 356                 OnchainTxHandler {
 357                         destination_script,
 358                         local_commitment: None,
 359                         local_htlc_sigs: None,
 360                         prev_local_commitment: None,
 361                         prev_local_htlc_sigs: None,
 362                         local_csv,
 363                         key_storage,
 364                         pending_claim_requests: HashMap::new(),
 365                         claimable_outpoints: HashMap::new(),
 366                         onchain_events_waiting_threshold_conf: HashMap::new(),
 367
 368                         secp_ctx: Secp256k1::new(),
 369                 }
 370         }
 371
 372         pub(super) fn get_witnesses_weight(inputs: &[InputDescriptors]) -> usize {
 373                 let mut tx_weight = 2; // count segwit flags
 374                 for inp in inputs {
 375                         // We use expected weight (and not actual) as signatures and time lock delays may vary
 376                         tx_weight +=  match inp {
 377                                 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
 378                                 &InputDescriptors::RevokedOfferedHTLC => {
 379                                         1 + 1 + 73 + 1 + 33 + 1 + 133
 380                                 },
 381                                 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
 382                                 &InputDescriptors::RevokedReceivedHTLC => {
 383                                         1 + 1 + 73 + 1 + 33 + 1 + 139
 384                                 },
 385                                 // number_of_witness_elements + sig_length + remotehtlc_sig  + preimage_length + preimage + witness_script_length + witness_script
 386                                 &InputDescriptors::OfferedHTLC => {
 387                                         1 + 1 + 73 + 1 + 32 + 1 + 133
 388                                 },
 389                                 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
 390                                 &InputDescriptors::ReceivedHTLC => {
 391                                         1 + 1 + 73 + 1 + 1 + 1 + 139
 392                                 },
 393                                 // number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
 394                                 &InputDescriptors::RevokedOutput => {
 395                                         1 + 1 + 73 + 1 + 1 + 1 + 77
 396                                 },
 397                         };
 398                 }
 399                 tx_weight
 400         }
 401
 402         /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
 403         /// output detection, we generate a first version of a claim tx and associate to it a height timer. A height timer is an absolute block
 404         /// height than once reached we should generate a new bumped "version" of the claim tx to be sure than we safely claim outputs before
 405         /// than our counterparty can do it too. If timelock expires soon, height timer is going to be scale down in consequence to increase
 406         /// frequency of the bump and so increase our bets of success.
 407         fn get_height_timer(current_height: u32, timelock_expiration: u32) -> u32 {
 408                 if timelock_expiration <= current_height + 3 {
 409                         return current_height + 1
 410                 } else if timelock_expiration - current_height <= 15 {
 411                         return current_height + 3
 412                 }
 413                 current_height + 15
 414         }
 415
 416         /// Lightning security model (i.e being able to redeem/timeout HTLC or penalize coutnerparty onchain) lays on the assumption of claim transactions getting confirmed before timelock expiration
 417         /// (CSV or CLTV following cases). In case of high-fee spikes, claim tx may stuck in the mempool, so you need to bump its feerate quickly using Replace-By-Fee or Child-Pay-For-Parent.
 418         fn generate_claim_tx<F: Deref, L: Deref>(&mut self, height: u32, cached_claim_datas: &ClaimTxBumpMaterial, fee_estimator: F, logger: L) -> Option<(Option<u32>, u64, Transaction)>
 419                 where F::Target: FeeEstimator,
 420                                         L::Target: Logger,
 421         {
 422                 if cached_claim_datas.per_input_material.len() == 0 { return None } // But don't prune pending claiming request yet, we may have to resurrect HTLCs
 423                 let mut inputs = Vec::new();
 424                 for outp in cached_claim_datas.per_input_material.keys() {
 425                         log_trace!(logger, "Outpoint {}:{}", outp.txid, outp.vout);
 426                         inputs.push(TxIn {
 427                                 previous_output: *outp,
 428                                 script_sig: Script::new(),
 429                                 sequence: 0xfffffffd,
 430                                 witness: Vec::new(),
 431                         });
 432                 }
 433                 let mut bumped_tx = Transaction {
 434                         version: 2,
 435                         lock_time: 0,
 436                         input: inputs,
 437                         output: vec![TxOut {
 438                                 script_pubkey: self.destination_script.clone(),
 439                                 value: 0
 440                         }],
 441                 };
 442
 443                 macro_rules! RBF_bump {
 444                         ($amount: expr, $old_feerate: expr, $fee_estimator: expr, $predicted_weight: expr) => {
 445                                 {
 446                                         let mut used_feerate;
 447                                         // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
 448                                         let new_fee = if $old_feerate < $fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) {
 449                                                 let mut value = $amount;
 450                                                 if subtract_high_prio_fee!(logger, $fee_estimator, value, $predicted_weight, used_feerate) {
 451                                                         // Overflow check is done in subtract_high_prio_fee
 452                                                         $amount - value
 453                                                 } else {
 454                                                         log_trace!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", $amount);
 455                                                         return None;
 456                                                 }
 457                                         // ...else just increase the previous feerate by 25% (because that's a nice number)
 458                                         } else {
 459                                                 let fee = $old_feerate * $predicted_weight / 750;
 460                                                 if $amount <= fee {
 461                                                         log_trace!(logger, "Can't 25% bump new claiming tx, amount {} is too small", $amount);
 462                                                         return None;
 463                                                 }
 464                                                 fee
 465                                         };
 466
 467                                         let previous_fee = $old_feerate * $predicted_weight / 1000;
 468                                         let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * $predicted_weight / 1000;
 469                                         // BIP 125 Opt-in Full Replace-by-Fee Signaling
 470                                         //      * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
 471                                         //      * 4. The replacement transaction must also pay for its own bandwidth at or above the rate set by the node's minimum relay fee setting.
 472                                         let new_fee = if new_fee < previous_fee + min_relay_fee {
 473                                                 new_fee + previous_fee + min_relay_fee - new_fee
 474                                         } else {
 475                                                 new_fee
 476                                         };
 477                                         Some((new_fee, new_fee * 1000 / $predicted_weight))
 478                                 }
 479                         }
 480                 }
 481
 482                 // Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we
 483                 // didn't receive confirmation of it before, or not enough reorg-safe depth on top of it).
 484                 let new_timer = Some(Self::get_height_timer(height, cached_claim_datas.soonest_timelock));
 485                 let mut inputs_witnesses_weight = 0;
 486                 let mut amt = 0;
 487                 let mut dynamic_fee = true;
 488                 for per_outp_material in cached_claim_datas.per_input_material.values() {
 489                         match per_outp_material {
 490                                 &InputMaterial::Revoked { ref witness_script, ref is_htlc, ref amount, .. } => {
 491                                         inputs_witnesses_weight += Self::get_witnesses_weight(if !is_htlc { &[InputDescriptors::RevokedOutput] } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::OfferedHTLC) { &[InputDescriptors::RevokedOfferedHTLC] } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::AcceptedHTLC) { &[InputDescriptors::RevokedReceivedHTLC] } else { unreachable!() });
 492                                         amt += *amount;
 493                                 },
 494                                 &InputMaterial::RemoteHTLC { ref preimage, ref amount, .. } => {
 495                                         inputs_witnesses_weight += Self::get_witnesses_weight(if preimage.is_some() { &[InputDescriptors::OfferedHTLC] } else { &[InputDescriptors::ReceivedHTLC] });
 496                                         amt += *amount;
 497                                 },
 498                                 &InputMaterial::LocalHTLC { .. } => {
 499                                         dynamic_fee = false;
 500                                 },
 501                                 &InputMaterial::Funding { .. } => {
 502                                         dynamic_fee = false;
 503                                 }
 504                         }
 505                 }
 506                 if dynamic_fee {
 507                         let predicted_weight = bumped_tx.get_weight() + inputs_witnesses_weight;
 508                         let mut new_feerate;
 509                         // If old feerate is 0, first iteration of this claim, use normal fee calculation
 510                         if cached_claim_datas.feerate_previous != 0 {
 511                                 if let Some((new_fee, feerate)) = RBF_bump!(amt, cached_claim_datas.feerate_previous, fee_estimator, predicted_weight as u64) {
 512                                         // If new computed fee is superior at the whole claimable amount burn all in fees
 513                                         if new_fee > amt {
 514                                                 bumped_tx.output[0].value = 0;
 515                                         } else {
 516                                                 bumped_tx.output[0].value = amt - new_fee;
 517                                         }
 518                                         new_feerate = feerate;
 519                                 } else { return None; }
 520                         } else {
 521                                 if subtract_high_prio_fee!(logger, fee_estimator, amt, predicted_weight, new_feerate) {
 522                                         bumped_tx.output[0].value = amt;
 523                                 } else { return None; }
 524                         }
 525                         assert!(new_feerate != 0);
 526
 527                         for (i, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() {
 528                                 match per_outp_material {
 529                                         &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount } => {
 530                                                 let sighash_parts = bip143::SighashComponents::new(&bumped_tx);
 531                                                 let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]);
 532                                                 let sig = self.secp_ctx.sign(&sighash, &key);
 533                                                 bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
 534                                                 bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
 535                                                 if *is_htlc {
 536                                                         bumped_tx.input[i].witness.push(pubkey.unwrap().clone().serialize().to_vec());
 537                                                 } else {
 538                                                         bumped_tx.input[i].witness.push(vec!(1));
 539                                                 }
 540                                                 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
 541                                                 log_trace!(logger, "Going to broadcast Penalty Transaction {} claiming revoked {} output {} from {} with new feerate {}...", bumped_tx.txid(), if !is_htlc { "to_local" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::OfferedHTLC) { "offered" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::AcceptedHTLC) { "received" } else { "" }, outp.vout, outp.txid, new_feerate);
 542                                         },
 543                                         &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => {
 544                                                 if !preimage.is_some() { bumped_tx.lock_time = *locktime }; // Right now we don't aggregate time-locked transaction, if we do we should set lock_time before to avoid breaking hash computation
 545                                                 let sighash_parts = bip143::SighashComponents::new(&bumped_tx);
 546                                                 let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]);
 547                                                 let sig = self.secp_ctx.sign(&sighash, &key);
 548                                                 bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
 549                                                 bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
 550                                                 if let &Some(preimage) = preimage {
 551                                                         bumped_tx.input[i].witness.push(preimage.clone().0.to_vec());
 552                                                 } else {
 553                                                         bumped_tx.input[i].witness.push(vec![]);
 554                                                 }
 555                                                 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
 556                                                 log_trace!(logger, "Going to broadcast Claim Transaction {} claiming remote {} htlc output {} from {} with new feerate {}...", bumped_tx.txid(), if preimage.is_some() { "offered" } else { "received" }, outp.vout, outp.txid, new_feerate);
 557                                         },
 558                                         _ => unreachable!()
 559                                 }
 560                         }
 561                         log_trace!(logger, "...with timer {}", new_timer.unwrap());
 562                         assert!(predicted_weight >= bumped_tx.get_weight());
 563                         return Some((new_timer, new_feerate, bumped_tx))
 564                 } else {
 565                         for (_, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() {
 566                                 match per_outp_material {
 567                                         &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
 568                                                 let htlc_tx = self.get_fully_signed_htlc_tx(outp, preimage);
 569                                                 if let Some(htlc_tx) = htlc_tx {
 570                                                         let feerate = (amount - htlc_tx.output[0].value) * 1000 / htlc_tx.get_weight() as u64;
 571                                                         // Timer set to $NEVER given we can't bump tx without anchor outputs
 572                                                         log_trace!(logger, "Going to broadcast Local HTLC-{} claiming HTLC output {} from {}...", if preimage.is_some() { "Success" } else { "Timeout" }, outp.vout, outp.txid);
 573                                                         return Some((None, feerate, htlc_tx));
 574                                                 }
 575                                                 return None;
 576                                         },
 577                                         &InputMaterial::Funding { ref funding_redeemscript } => {
 578                                                 let signed_tx = self.get_fully_signed_local_tx(funding_redeemscript).unwrap();
 579                                                 // Timer set to $NEVER given we can't bump tx without anchor outputs
 580                                                 log_trace!(logger, "Going to broadcast Local Transaction {} claiming funding output {} from {}...", signed_tx.txid(), outp.vout, outp.txid);
 581                                                 return Some((None, self.local_commitment.as_ref().unwrap().feerate_per_kw, signed_tx));
 582                                         }
 583                                         _ => unreachable!()
 584                                 }
 585                         }
 586                 }
 587                 None
 588         }
 589
 590         pub(super) fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, txn_matched: &[&Transaction], claimable_outpoints: Vec<ClaimRequest>, height: u32, broadcaster: B, fee_estimator: F, logger: L)
 591                 where B::Target: BroadcasterInterface,
 592                       F::Target: FeeEstimator,
 593                                         L::Target: Logger,
 594         {
 595                 log_trace!(logger, "Block at height {} connected with {} claim requests", height, claimable_outpoints.len());
 596                 let mut new_claims = Vec::new();
 597                 let mut aggregated_claim = HashMap::new();
 598                 let mut aggregated_soonest = ::std::u32::MAX;
 599
 600                 // Try to aggregate outputs if their timelock expiration isn't imminent (absolute_timelock
 601                 // <= CLTV_SHARED_CLAIM_BUFFER) and they don't require an immediate nLockTime (aggregable).
 602                 for req in claimable_outpoints {
 603                         // Don't claim a outpoint twice that would be bad for privacy and may uselessly lock a CPFP input for a while
 604                         if let Some(_) = self.claimable_outpoints.get(&req.outpoint) { log_trace!(logger, "Bouncing off outpoint {}:{}, already registered its claiming request", req.outpoint.txid, req.outpoint.vout); } else {
 605                                 log_trace!(logger, "Test if outpoint can be aggregated with expiration {} against {}", req.absolute_timelock, height + CLTV_SHARED_CLAIM_BUFFER);
 606                                 if req.absolute_timelock <= height + CLTV_SHARED_CLAIM_BUFFER || !req.aggregable { // Don't aggregate if outpoint absolute timelock is soon or marked as non-aggregable
 607                                         let mut single_input = HashMap::new();
 608                                         single_input.insert(req.outpoint, req.witness_data);
 609                                         new_claims.push((req.absolute_timelock, single_input));
 610                                 } else {
 611                                         aggregated_claim.insert(req.outpoint, req.witness_data);
 612                                         if req.absolute_timelock < aggregated_soonest {
 613                                                 aggregated_soonest = req.absolute_timelock;
 614                                         }
 615                                 }
 616                         }
 617                 }
 618                 new_claims.push((aggregated_soonest, aggregated_claim));
 619
 620                 // Generate claim transactions and track them to bump if necessary at
 621                 // height timer expiration (i.e in how many blocks we're going to take action).
 622                 for (soonest_timelock, claim) in new_claims.drain(..) {
 623                         let mut claim_material = ClaimTxBumpMaterial { height_timer: None, feerate_previous: 0, soonest_timelock, per_input_material: claim };
 624                         if let Some((new_timer, new_feerate, tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator, &*logger) {
 625                                 claim_material.height_timer = new_timer;
 626                                 claim_material.feerate_previous = new_feerate;
 627                                 let txid = tx.txid();
 628                                 for k in claim_material.per_input_material.keys() {
 629                                         log_trace!(logger, "Registering claiming request for {}:{}", k.txid, k.vout);
 630                                         self.claimable_outpoints.insert(k.clone(), (txid, height));
 631                                 }
 632                                 self.pending_claim_requests.insert(txid, claim_material);
 633                                 log_trace!(logger, "Broadcast onchain {}", log_tx!(tx));
 634                                 broadcaster.broadcast_transaction(&tx);
 635                         }
 636                 }
 637
 638                 let mut bump_candidates = HashMap::new();
 639                 for tx in txn_matched {
 640                         // Scan all input to verify is one of the outpoint spent is of interest for us
 641                         let mut claimed_outputs_material = Vec::new();
 642                         for inp in &tx.input {
 643                                 if let Some(first_claim_txid_height) = self.claimable_outpoints.get(&inp.previous_output) {
 644                                         // If outpoint has claim request pending on it...
 645                                         if let Some(claim_material) = self.pending_claim_requests.get_mut(&first_claim_txid_height.0) {
 646                                                 //... we need to verify equality between transaction outpoints and claim request
 647                                                 // outpoints to know if transaction is the original claim or a bumped one issued
 648                                                 // by us.
 649                                                 let mut set_equality = true;
 650                                                 if claim_material.per_input_material.len() != tx.input.len() {
 651                                                         set_equality = false;
 652                                                 } else {
 653                                                         for (claim_inp, tx_inp) in claim_material.per_input_material.keys().zip(tx.input.iter()) {
 654                                                                 if *claim_inp != tx_inp.previous_output {
 655                                                                         set_equality = false;
 656                                                                 }
 657                                                         }
 658                                                 }
 659
 660                                                 macro_rules! clean_claim_request_after_safety_delay {
 661                                                         () => {
 662                                                                 let new_event = OnchainEvent::Claim { claim_request: first_claim_txid_height.0.clone() };
 663                                                                 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
 664                                                                         hash_map::Entry::Occupied(mut entry) => {
 665                                                                                 if !entry.get().contains(&new_event) {
 666                                                                                         entry.get_mut().push(new_event);
 667                                                                                 }
 668                                                                         },
 669                                                                         hash_map::Entry::Vacant(entry) => {
 670                                                                                 entry.insert(vec![new_event]);
 671                                                                         }
 672                                                                 }
 673                                                         }
 674                                                 }
 675
 676                                                 // If this is our transaction (or our counterparty spent all the outputs
 677                                                 // before we could anyway with same inputs order than us), wait for
 678                                                 // ANTI_REORG_DELAY and clean the RBF tracking map.
 679                                                 if set_equality {
 680                                                         clean_claim_request_after_safety_delay!();
 681                                                 } else { // If false, generate new claim request with update outpoint set
 682                                                         let mut at_least_one_drop = false;
 683                                                         for input in tx.input.iter() {
 684                                                                 if let Some(input_material) = claim_material.per_input_material.remove(&input.previous_output) {
 685                                                                         claimed_outputs_material.push((input.previous_output, input_material));
 686                                                                         at_least_one_drop = true;
 687                                                                 }
 688                                                                 // If there are no outpoints left to claim in this request, drop it entirely after ANTI_REORG_DELAY.
 689                                                                 if claim_material.per_input_material.is_empty() {
 690                                                                         clean_claim_request_after_safety_delay!();
 691                                                                 }
 692                                                         }
 693                                                         //TODO: recompute soonest_timelock to avoid wasting a bit on fees
 694                                                         if at_least_one_drop {
 695                                                                 bump_candidates.insert(first_claim_txid_height.0.clone(), claim_material.clone());
 696                                                         }
 697                                                 }
 698                                                 break; //No need to iterate further, either tx is our or their
 699                                         } else {
 700                                                 panic!("Inconsistencies between pending_claim_requests map and claimable_outpoints map");
 701                                         }
 702                                 }
 703                         }
 704                         for (outpoint, input_material) in claimed_outputs_material.drain(..) {
 705                                 let new_event = OnchainEvent::ContentiousOutpoint { outpoint, input_material };
 706                                 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
 707                                         hash_map::Entry::Occupied(mut entry) => {
 708                                                 if !entry.get().contains(&new_event) {
 709                                                         entry.get_mut().push(new_event);
 710                                                 }
 711                                         },
 712                                         hash_map::Entry::Vacant(entry) => {
 713                                                 entry.insert(vec![new_event]);
 714                                         }
 715                                 }
 716                         }
 717                 }
 718
 719                 // After security delay, either our claim tx got enough confs or outpoint is definetely out of reach
 720                 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
 721                         for ev in events {
 722                                 match ev {
 723                                         OnchainEvent::Claim { claim_request } => {
 724                                                 // We may remove a whole set of claim outpoints here, as these one may have
 725                                                 // been aggregated in a single tx and claimed so atomically
 726                                                 if let Some(bump_material) = self.pending_claim_requests.remove(&claim_request) {
 727                                                         for outpoint in bump_material.per_input_material.keys() {
 728                                                                 self.claimable_outpoints.remove(&outpoint);
 729                                                         }
 730                                                 }
 731                                         },
 732                                         OnchainEvent::ContentiousOutpoint { outpoint, .. } => {
 733                                                 self.claimable_outpoints.remove(&outpoint);
 734                                         }
 735                                 }
 736                         }
 737                 }
 738
 739                 // Check if any pending claim request must be rescheduled
 740                 for (first_claim_txid, ref claim_data) in self.pending_claim_requests.iter() {
 741                         if let Some(h) = claim_data.height_timer {
 742                                 if h == height {
 743                                         bump_candidates.insert(*first_claim_txid, (*claim_data).clone());
 744                                 }
 745                         }
 746                 }
 747
 748                 // Build, bump and rebroadcast tx accordingly
 749                 log_trace!(logger, "Bumping {} candidates", bump_candidates.len());
 750                 for (first_claim_txid, claim_material) in bump_candidates.iter() {
 751                         if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator, &*logger) {
 752                                 log_trace!(logger, "Broadcast onchain {}", log_tx!(bump_tx));
 753                                 broadcaster.broadcast_transaction(&bump_tx);
 754                                 if let Some(claim_material) = self.pending_claim_requests.get_mut(first_claim_txid) {
 755                                         claim_material.height_timer = new_timer;
 756                                         claim_material.feerate_previous = new_feerate;
 757                                 }
 758                         }
 759                 }
 760         }
 761
 762         pub(super) fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, broadcaster: B, fee_estimator: F, logger: L)
 763                 where B::Target: BroadcasterInterface,
 764                       F::Target: FeeEstimator,
 765                                         L::Target: Logger,
 766         {
 767                 let mut bump_candidates = HashMap::new();
 768                 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
 769                         //- our claim tx on a commitment tx output
 770                         //- resurect outpoint back in its claimable set and regenerate tx
 771                         for ev in events {
 772                                 match ev {
 773                                         OnchainEvent::ContentiousOutpoint { outpoint, input_material } => {
 774                                                 if let Some(ancestor_claimable_txid) = self.claimable_outpoints.get(&outpoint) {
 775                                                         if let Some(claim_material) = self.pending_claim_requests.get_mut(&ancestor_claimable_txid.0) {
 776                                                                 claim_material.per_input_material.insert(outpoint, input_material);
 777                                                                 // Using a HashMap guarantee us than if we have multiple outpoints getting
 778                                                                 // resurrected only one bump claim tx is going to be broadcast
 779                                                                 bump_candidates.insert(ancestor_claimable_txid.clone(), claim_material.clone());
 780                                                         }
 781                                                 }
 782                                         },
 783                                         _ => {},
 784                                 }
 785                         }
 786                 }
 787                 for (_, claim_material) in bump_candidates.iter_mut() {
 788                         if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator, &*logger) {
 789                                 claim_material.height_timer = new_timer;
 790                                 claim_material.feerate_previous = new_feerate;
 791                                 broadcaster.broadcast_transaction(&bump_tx);
 792                         }
 793                 }
 794                 for (ancestor_claim_txid, claim_material) in bump_candidates.drain() {
 795                         self.pending_claim_requests.insert(ancestor_claim_txid.0, claim_material);
 796                 }
 797                 //TODO: if we implement cross-block aggregated claim transaction we need to refresh set of outpoints and regenerate tx but
 798                 // right now if one of the outpoint get disconnected, just erase whole pending claim request.
 799                 let mut remove_request = Vec::new();
 800                 self.claimable_outpoints.retain(|_, ref v|
 801                         if v.1 == height {
 802                         remove_request.push(v.0.clone());
 803                         false
 804                         } else { true });
 805                 for req in remove_request {
 806                         self.pending_claim_requests.remove(&req);
 807                 }
 808         }
 809
 810         pub(super) fn provide_latest_local_tx(&mut self, tx: LocalCommitmentTransaction) -> Result<(), ()> {
 811                 // To prevent any unsafe state discrepancy between offchain and onchain, once local
 812                 // commitment transaction has been signed due to an event (either block height for
 813                 // HTLC-timeout or channel force-closure), don't allow any further update of local
 814                 // commitment transaction view to avoid delivery of revocation secret to counterparty
 815                 // for the aformentionned signed transaction.
 816                 if self.local_htlc_sigs.is_some() || self.prev_local_htlc_sigs.is_some() {
 817                         return Err(());
 818                 }
 819                 self.prev_local_commitment = self.local_commitment.take();
 820                 self.local_commitment = Some(tx);
 821                 Ok(())
 822         }
 823
 824         fn sign_latest_local_htlcs(&mut self) {
 825                 if let Some(ref local_commitment) = self.local_commitment {
 826                         if let Ok(sigs) = self.key_storage.sign_local_commitment_htlc_transactions(local_commitment, self.local_csv, &self.secp_ctx) {
 827                                 self.local_htlc_sigs = Some(Vec::new());
 828                                 let ret = self.local_htlc_sigs.as_mut().unwrap();
 829                                 for (htlc_idx, (local_sig, &(ref htlc, _))) in sigs.iter().zip(local_commitment.per_htlc.iter()).enumerate() {
 830                                         if let Some(tx_idx) = htlc.transaction_output_index {
 831                                                 if ret.len() <= tx_idx as usize { ret.resize(tx_idx as usize + 1, None); }
 832                                                 ret[tx_idx as usize] = Some((htlc_idx, local_sig.expect("Did not receive a signature for a non-dust HTLC")));
 833                                         } else {
 834                                                 assert!(local_sig.is_none(), "Received a signature for a dust HTLC");
 835                                         }
 836                                 }
 837                         }
 838                 }
 839         }
 840         fn sign_prev_local_htlcs(&mut self) {
 841                 if let Some(ref local_commitment) = self.prev_local_commitment {
 842                         if let Ok(sigs) = self.key_storage.sign_local_commitment_htlc_transactions(local_commitment, self.local_csv, &self.secp_ctx) {
 843                                 self.prev_local_htlc_sigs = Some(Vec::new());
 844                                 let ret = self.prev_local_htlc_sigs.as_mut().unwrap();
 845                                 for (htlc_idx, (local_sig, &(ref htlc, _))) in sigs.iter().zip(local_commitment.per_htlc.iter()).enumerate() {
 846                                         if let Some(tx_idx) = htlc.transaction_output_index {
 847                                                 if ret.len() <= tx_idx as usize { ret.resize(tx_idx as usize + 1, None); }
 848                                                 ret[tx_idx as usize] = Some((htlc_idx, local_sig.expect("Did not receive a signature for a non-dust HTLC")));
 849                                         } else {
 850                                                 assert!(local_sig.is_none(), "Received a signature for a dust HTLC");
 851                                         }
 852                                 }
 853                         }
 854                 }
 855         }
 856
 857         //TODO: getting lastest local transactions should be infaillible and result in us "force-closing the channel", but we may
 858         // have empty local commitment transaction if a ChannelMonitor is asked to force-close just after Channel::get_outbound_funding_created,
 859         // before providing a initial commitment transaction. For outbound channel, init ChannelMonitor at Channel::funding_signed, there is nothing
 860         // to monitor before.
 861         pub(super) fn get_fully_signed_local_tx(&mut self, funding_redeemscript: &Script) -> Option<Transaction> {
 862                 if let Some(ref mut local_commitment) = self.local_commitment {
 863                         match self.key_storage.sign_local_commitment(local_commitment, &self.secp_ctx) {
 864                                 Ok(sig) => Some(local_commitment.add_local_sig(funding_redeemscript, sig)),
 865                                 Err(_) => return None,
 866                         }
 867                 } else {
 868                         None
 869                 }
 870         }
 871
 872         #[cfg(test)]
 873         pub(super) fn get_fully_signed_copy_local_tx(&mut self, funding_redeemscript: &Script) -> Option<Transaction> {
 874                 if let Some(ref mut local_commitment) = self.local_commitment {
 875                         let local_commitment = local_commitment.clone();
 876                         match self.key_storage.sign_local_commitment(&local_commitment, &self.secp_ctx) {
 877                                 Ok(sig) => Some(local_commitment.add_local_sig(funding_redeemscript, sig)),
 878                                 Err(_) => return None,
 879                         }
 880                 } else {
 881                         None
 882                 }
 883         }
 884
 885         pub(super) fn get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
 886                 let mut htlc_tx = None;
 887                 if self.local_commitment.is_some() {
 888                         let commitment_txid = self.local_commitment.as_ref().unwrap().txid();
 889                         if commitment_txid == outp.txid {
 890                                 self.sign_latest_local_htlcs();
 891                                 if let &Some(ref htlc_sigs) = &self.local_htlc_sigs {
 892                                         let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
 893                                         htlc_tx = Some(self.local_commitment.as_ref().unwrap()
 894                                                 .get_signed_htlc_tx(*htlc_idx, htlc_sig, preimage, self.local_csv));
 895                                 }
 896                         }
 897                 }
 898                 if self.prev_local_commitment.is_some() {
 899                         let commitment_txid = self.prev_local_commitment.as_ref().unwrap().txid();
 900                         if commitment_txid == outp.txid {
 901                                 self.sign_prev_local_htlcs();
 902                                 if let &Some(ref htlc_sigs) = &self.prev_local_htlc_sigs {
 903                                         let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
 904                                         htlc_tx = Some(self.prev_local_commitment.as_ref().unwrap()
 905                                                 .get_signed_htlc_tx(*htlc_idx, htlc_sig, preimage, self.local_csv));
 906                                 }
 907                         }
 908                 }
 909                 htlc_tx
 910         }
 911
 912         #[cfg(test)]
 913         pub(super) fn unsafe_get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
 914                 let latest_had_sigs = self.local_htlc_sigs.is_some();
 915                 let prev_had_sigs = self.prev_local_htlc_sigs.is_some();
 916                 let ret = self.get_fully_signed_htlc_tx(outp, preimage);
 917                 if !latest_had_sigs {
 918                         self.local_htlc_sigs = None;
 919                 }
 920                 if !prev_had_sigs {
 921                         self.prev_local_htlc_sigs = None;
 922                 }
 923                 ret
 924         }
 925 }