_ Git - rust-lightning/blob - lightning/src/chain/package.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! Various utilities to assemble claimable outpoints in package of one or more transactions. Those
  11 //! packages are attached metadata, guiding their aggregable or fee-bumping re-schedule. This file
  12 //! also includes witness weight computation and fee computation methods.
  13
  14 use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
  15 use bitcoin::blockdata::transaction::{TxOut,TxIn, Transaction, SigHashType};
  16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
  17 use bitcoin::blockdata::script::Script;
  18
  19 use bitcoin::hash_types::Txid;
  20
  21 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
  22
  23 use ln::PaymentPreimage;
  24 use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment};
  25 use ln::chan_utils;
  26 use ln::msgs::DecodeError;
  27 use chain::chaininterface::{FeeEstimator, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
  28 use chain::keysinterface::Sign;
  29 use chain::onchaintx::OnchainTxHandler;
  30 use util::byte_utils;
  31 use util::logger::Logger;
  32 use util::ser::{Readable, Writer, Writeable};
  33
  34 use core::cmp;
  35 use core::mem;
  36 use core::ops::Deref;
  37
  38 const MAX_ALLOC_SIZE: usize = 64*1024;
  39
  40
  41 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
  42 pub(crate) const WEIGHT_REVOKED_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 133;
  43 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
  44 pub(crate) const WEIGHT_REVOKED_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 +  139;
  45 // number_of_witness_elements + sig_length + counterpartyhtlc_sig  + preimage_length + preimage + witness_script_length + witness_script
  46 pub(crate) const WEIGHT_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 32 + 1 + 133;
  47 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
  48 pub(crate) const WEIGHT_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 139;
  49 // number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
  50 pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77;
  51
  52 /// Height delay at which transactions are fee-bumped/rebroadcasted with a low priority.
  53 const LOW_FREQUENCY_BUMP_INTERVAL: u32 = 15;
  54 /// Height delay at which transactions are fee-bumped/rebroadcasted with a middle priority.
  55 const MIDDLE_FREQUENCY_BUMP_INTERVAL: u32 = 3;
  56 /// Height delay at which transactions are fee-bumped/rebroadcasted with a high priority.
  57 const HIGH_FREQUENCY_BUMP_INTERVAL: u32 = 1;
  58
  59 /// A struct to describe a revoked output and corresponding information to generate a solving
  60 /// witness spending a commitment `to_local` output or a second-stage HTLC transaction output.
  61 ///
  62 /// CSV and pubkeys are used as part of a witnessScript redeeming a balance output, amount is used
  63 /// as part of the signature hash and revocation secret to generate a satisfying witness.
  64 #[derive(Clone, PartialEq)]
  65 pub(crate) struct RevokedOutput {
  66         per_commitment_point: PublicKey,
  67         counterparty_delayed_payment_base_key: PublicKey,
  68         counterparty_htlc_base_key: PublicKey,
  69         per_commitment_key: SecretKey,
  70         weight: u64,
  71         amount: u64,
  72         on_counterparty_tx_csv: u16,
  73 }
  74
  75 impl RevokedOutput {
  76         pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, per_commitment_key: SecretKey, amount: u64, on_counterparty_tx_csv: u16) -> Self {
  77                 RevokedOutput {
  78                         per_commitment_point,
  79                         counterparty_delayed_payment_base_key,
  80                         counterparty_htlc_base_key,
  81                         per_commitment_key,
  82                         weight: WEIGHT_REVOKED_OUTPUT,
  83                         amount,
  84                         on_counterparty_tx_csv
  85                 }
  86         }
  87 }
  88
  89 impl_writeable_tlv_based!(RevokedOutput, {
  90         (0, per_commitment_point),
  91         (2, counterparty_delayed_payment_base_key),
  92         (4, counterparty_htlc_base_key),
  93         (6, per_commitment_key),
  94         (8, weight),
  95         (10, amount),
  96         (12, on_counterparty_tx_csv),
  97 }, {}, {});
  98
  99 /// A struct to describe a revoked offered output and corresponding information to generate a
 100 /// solving witness.
 101 ///
 102 /// HTLCOuputInCommitment (hash timelock, direction) and pubkeys are used to generate a suitable
 103 /// witnessScript.
 104 ///
 105 /// CSV is used as part of a witnessScript redeeming a balance output, amount is used as part
 106 /// of the signature hash and revocation secret to generate a satisfying witness.
 107 #[derive(Clone, PartialEq)]
 108 pub(crate) struct RevokedHTLCOutput {
 109         per_commitment_point: PublicKey,
 110         counterparty_delayed_payment_base_key: PublicKey,
 111         counterparty_htlc_base_key: PublicKey,
 112         per_commitment_key: SecretKey,
 113         weight: u64,
 114         amount: u64,
 115         htlc: HTLCOutputInCommitment,
 116 }
 117
 118 impl RevokedHTLCOutput {
 119         pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, per_commitment_key: SecretKey, amount: u64, htlc: HTLCOutputInCommitment) -> Self {
 120                 let weight = if htlc.offered { WEIGHT_REVOKED_OFFERED_HTLC } else { WEIGHT_REVOKED_RECEIVED_HTLC };
 121                 RevokedHTLCOutput {
 122                         per_commitment_point,
 123                         counterparty_delayed_payment_base_key,
 124                         counterparty_htlc_base_key,
 125                         per_commitment_key,
 126                         weight,
 127                         amount,
 128                         htlc
 129                 }
 130         }
 131 }
 132
 133 impl_writeable_tlv_based!(RevokedHTLCOutput, {
 134         (0, per_commitment_point),
 135         (2, counterparty_delayed_payment_base_key),
 136         (4, counterparty_htlc_base_key),
 137         (6, per_commitment_key),
 138         (8, weight),
 139         (10, amount),
 140         (12, htlc),
 141 }, {}, {});
 142
 143 /// A struct to describe a HTLC output on a counterparty commitment transaction.
 144 ///
 145 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
 146 /// witnessScript.
 147 ///
 148 /// The preimage is used as part of the witness.
 149 #[derive(Clone, PartialEq)]
 150 pub(crate) struct CounterpartyOfferedHTLCOutput {
 151         per_commitment_point: PublicKey,
 152         counterparty_delayed_payment_base_key: PublicKey,
 153         counterparty_htlc_base_key: PublicKey,
 154         preimage: PaymentPreimage,
 155         htlc: HTLCOutputInCommitment
 156 }
 157
 158 impl CounterpartyOfferedHTLCOutput {
 159         pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, preimage: PaymentPreimage, htlc: HTLCOutputInCommitment) -> Self {
 160                 CounterpartyOfferedHTLCOutput {
 161                         per_commitment_point,
 162                         counterparty_delayed_payment_base_key,
 163                         counterparty_htlc_base_key,
 164                         preimage,
 165                         htlc
 166                 }
 167         }
 168 }
 169
 170 impl_writeable_tlv_based!(CounterpartyOfferedHTLCOutput, {
 171         (0, per_commitment_point),
 172         (2, counterparty_delayed_payment_base_key),
 173         (4, counterparty_htlc_base_key),
 174         (6, preimage),
 175         (8, htlc),
 176 }, {}, {});
 177
 178 /// A struct to describe a HTLC output on a counterparty commitment transaction.
 179 ///
 180 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
 181 /// witnessScript.
 182 #[derive(Clone, PartialEq)]
 183 pub(crate) struct CounterpartyReceivedHTLCOutput {
 184         per_commitment_point: PublicKey,
 185         counterparty_delayed_payment_base_key: PublicKey,
 186         counterparty_htlc_base_key: PublicKey,
 187         htlc: HTLCOutputInCommitment
 188 }
 189
 190 impl CounterpartyReceivedHTLCOutput {
 191         pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, htlc: HTLCOutputInCommitment) -> Self {
 192                 CounterpartyReceivedHTLCOutput {
 193                         per_commitment_point,
 194                         counterparty_delayed_payment_base_key,
 195                         counterparty_htlc_base_key,
 196                         htlc
 197                 }
 198         }
 199 }
 200
 201 impl_writeable_tlv_based!(CounterpartyReceivedHTLCOutput, {
 202         (0, per_commitment_point),
 203         (2, counterparty_delayed_payment_base_key),
 204         (4, counterparty_htlc_base_key),
 205         (6, htlc),
 206 }, {}, {});
 207
 208 /// A struct to describe a HTLC output on holder commitment transaction.
 209 ///
 210 /// Either offered or received, the amount is always used as part of the bip143 sighash.
 211 /// Preimage is only included as part of the witness in former case.
 212 #[derive(Clone, PartialEq)]
 213 pub(crate) struct HolderHTLCOutput {
 214         preimage: Option<PaymentPreimage>,
 215         amount: u64,
 216         /// Defaults to 0 for HTLC-Success transactions, which have no expiry
 217         cltv_expiry: u32,
 218 }
 219
 220 impl HolderHTLCOutput {
 221         pub(crate) fn build_offered(amount: u64, cltv_expiry: u32) -> Self {
 222                 HolderHTLCOutput {
 223                         preimage: None,
 224                         amount,
 225                         cltv_expiry,
 226                 }
 227         }
 228
 229         pub(crate) fn build_accepted(preimage: PaymentPreimage, amount: u64) -> Self {
 230                 HolderHTLCOutput {
 231                         preimage: Some(preimage),
 232                         amount,
 233                         cltv_expiry: 0,
 234                 }
 235         }
 236 }
 237
 238 impl_writeable_tlv_based!(HolderHTLCOutput, {
 239         (0, amount),
 240         (2, cltv_expiry),
 241 }, {
 242         (4, preimage),
 243 }, {});
 244
 245 /// A struct to describe the channel output on the funding transaction.
 246 ///
 247 /// witnessScript is used as part of the witness redeeming the funding utxo.
 248 #[derive(Clone, PartialEq)]
 249 pub(crate) struct HolderFundingOutput {
 250         funding_redeemscript: Script,
 251 }
 252
 253 impl HolderFundingOutput {
 254         pub(crate) fn build(funding_redeemscript: Script) -> Self {
 255                 HolderFundingOutput {
 256                         funding_redeemscript,
 257                 }
 258         }
 259 }
 260
 261 impl_writeable_tlv_based!(HolderFundingOutput, {
 262         (0, funding_redeemscript),
 263 }, {}, {});
 264
 265 /// A wrapper encapsulating all in-protocol differing outputs types.
 266 ///
 267 /// The generic API offers access to an outputs common attributes or allow transformation such as
 268 /// finalizing an input claiming the output.
 269 #[derive(Clone, PartialEq)]
 270 pub(crate) enum PackageSolvingData {
 271         RevokedOutput(RevokedOutput),
 272         RevokedHTLCOutput(RevokedHTLCOutput),
 273         CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput),
 274         CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput),
 275         HolderHTLCOutput(HolderHTLCOutput),
 276         HolderFundingOutput(HolderFundingOutput),
 277 }
 278
 279 impl PackageSolvingData {
 280         fn amount(&self) -> u64 {
 281                 let amt = match self {
 282                         PackageSolvingData::RevokedOutput(ref outp) => { outp.amount },
 283                         PackageSolvingData::RevokedHTLCOutput(ref outp) => { outp.amount },
 284                         PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => { outp.htlc.amount_msat / 1000 },
 285                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => { outp.htlc.amount_msat / 1000 },
 286                         // Note: Currently, amounts of holder outputs spending witnesses aren't used
 287                         // as we can't malleate spending package to increase their feerate. This
 288                         // should change with the remaining anchor output patchset.
 289                         PackageSolvingData::HolderHTLCOutput(..) => { unreachable!() },
 290                         PackageSolvingData::HolderFundingOutput(..) => { unreachable!() },
 291                 };
 292                 amt
 293         }
 294         fn weight(&self) -> usize {
 295                 let weight = match self {
 296                         PackageSolvingData::RevokedOutput(ref outp) => { outp.weight as usize },
 297                         PackageSolvingData::RevokedHTLCOutput(ref outp) => { outp.weight as usize },
 298                         PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { WEIGHT_OFFERED_HTLC as usize },
 299                         PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { WEIGHT_RECEIVED_HTLC as usize },
 300                         // Note: Currently, weights of holder outputs spending witnesses aren't used
 301                         // as we can't malleate spending package to increase their feerate. This
 302                         // should change with the remaining anchor output patchset.
 303                         PackageSolvingData::HolderHTLCOutput(..) => { unreachable!() },
 304                         PackageSolvingData::HolderFundingOutput(..) => { unreachable!() },
 305                 };
 306                 weight
 307         }
 308         fn is_compatible(&self, input: &PackageSolvingData) -> bool {
 309                 match self {
 310                         PackageSolvingData::RevokedOutput(..) => {
 311                                 match input {
 312                                         PackageSolvingData::RevokedHTLCOutput(..) => { true },
 313                                         PackageSolvingData::RevokedOutput(..) => { true },
 314                                         _ => { false }
 315                                 }
 316                         },
 317                         PackageSolvingData::RevokedHTLCOutput(..) => {
 318                                 match input {
 319                                         PackageSolvingData::RevokedOutput(..) => { true },
 320                                         PackageSolvingData::RevokedHTLCOutput(..) => { true },
 321                                         _ => { false }
 322                                 }
 323                         },
 324                         _ => { mem::discriminant(self) == mem::discriminant(&input) }
 325                 }
 326         }
 327         fn finalize_input<Signer: Sign>(&self, bumped_tx: &mut Transaction, i: usize, onchain_handler: &mut OnchainTxHandler<Signer>) -> bool {
 328                 match self {
 329                         PackageSolvingData::RevokedOutput(ref outp) => {
 330                                 if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
 331                                         let witness_script = chan_utils::get_revokeable_redeemscript(&chan_keys.revocation_key, outp.on_counterparty_tx_csv, &chan_keys.broadcaster_delayed_payment_key);
 332                                         //TODO: should we panic on signer failure ?
 333                                         if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_output(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &onchain_handler.secp_ctx) {
 334                                                 bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
 335                                                 bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
 336                                                 bumped_tx.input[i].witness.push(vec!(1));
 337                                                 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
 338                                         } else { return false; }
 339                                 }
 340                         },
 341                         PackageSolvingData::RevokedHTLCOutput(ref outp) => {
 342                                 if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
 343                                         let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
 344                                         //TODO: should we panic on signer failure ?
 345                                         if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_htlc(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &outp.htlc, &onchain_handler.secp_ctx) {
 346                                                 bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
 347                                                 bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
 348                                                 bumped_tx.input[i].witness.push(chan_keys.revocation_key.clone().serialize().to_vec());
 349                                                 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
 350                                         } else { return false; }
 351                                 }
 352                         },
 353                         PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => {
 354                                 if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
 355                                         let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
 356
 357                                         if let Ok(sig) = onchain_handler.signer.sign_counterparty_htlc_transaction(&bumped_tx, i, &outp.htlc.amount_msat / 1000, &outp.per_commitment_point, &outp.htlc, &onchain_handler.secp_ctx) {
 358                                                 bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
 359                                                 bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
 360                                                 bumped_tx.input[i].witness.push(outp.preimage.0.to_vec());
 361                                                 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
 362                                         }
 363                                 }
 364                         },
 365                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => {
 366                                 if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
 367                                         let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
 368
 369                                         bumped_tx.lock_time = outp.htlc.cltv_expiry; // Right now we don't aggregate time-locked transaction, if we do we should set lock_time before to avoid breaking hash computation
 370                                         if let Ok(sig) = onchain_handler.signer.sign_counterparty_htlc_transaction(&bumped_tx, i, &outp.htlc.amount_msat / 1000, &outp.per_commitment_point, &outp.htlc, &onchain_handler.secp_ctx) {
 371                                                 bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
 372                                                 bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
 373                                                 // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
 374                                                 bumped_tx.input[i].witness.push(vec![]);
 375                                                 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
 376                                         }
 377                                 }
 378                         },
 379                         _ => { panic!("API Error!"); }
 380                 }
 381                 true
 382         }
 383         fn get_finalized_tx<Signer: Sign>(&self, outpoint: &BitcoinOutPoint, onchain_handler: &mut OnchainTxHandler<Signer>) -> Option<Transaction> {
 384                 match self {
 385                         PackageSolvingData::HolderHTLCOutput(ref outp) => { return onchain_handler.get_fully_signed_htlc_tx(outpoint, &outp.preimage); }
 386                         PackageSolvingData::HolderFundingOutput(ref outp) => { return Some(onchain_handler.get_fully_signed_holder_tx(&outp.funding_redeemscript)); }
 387                         _ => { panic!("API Error!"); }
 388                 }
 389         }
 390         fn absolute_tx_timelock(&self, output_conf_height: u32) -> u32 {
 391                 // Get the absolute timelock at which this output can be spent given the height at which
 392                 // this output was confirmed. We use `output_conf_height + 1` as a safe default as we can
 393                 // be confirmed in the next block and transactions with time lock `current_height + 1`
 394                 // always propagate.
 395                 let absolute_timelock = match self {
 396                         PackageSolvingData::RevokedOutput(_) => output_conf_height + 1,
 397                         PackageSolvingData::RevokedHTLCOutput(_) => output_conf_height + 1,
 398                         PackageSolvingData::CounterpartyOfferedHTLCOutput(_) => output_conf_height + 1,
 399                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => std::cmp::max(outp.htlc.cltv_expiry, output_conf_height + 1),
 400                         PackageSolvingData::HolderHTLCOutput(ref outp) => std::cmp::max(outp.cltv_expiry, output_conf_height + 1),
 401                         PackageSolvingData::HolderFundingOutput(_) => output_conf_height + 1,
 402                 };
 403                 absolute_timelock
 404         }
 405 }
 406
 407 impl Writeable for PackageSolvingData {
 408         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 409                 match self {
 410                         PackageSolvingData::RevokedOutput(ref revoked_outp) => {
 411                                 0u8.write(writer)?;
 412                                 revoked_outp.write(writer)?;
 413                         },
 414                         PackageSolvingData::RevokedHTLCOutput(ref revoked_outp) => {
 415                                 1u8.write(writer)?;
 416                                 revoked_outp.write(writer)?;
 417                         },
 418                         PackageSolvingData::CounterpartyOfferedHTLCOutput(ref counterparty_outp) => {
 419                                 2u8.write(writer)?;
 420                                 counterparty_outp.write(writer)?;
 421                         },
 422                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref counterparty_outp) => {
 423                                 3u8.write(writer)?;
 424                                 counterparty_outp.write(writer)?;
 425                         },
 426                         PackageSolvingData::HolderHTLCOutput(ref holder_outp) => {
 427                                 4u8.write(writer)?;
 428                                 holder_outp.write(writer)?;
 429                         },
 430                         PackageSolvingData::HolderFundingOutput(ref funding_outp) => {
 431                                 5u8.write(writer)?;
 432                                 funding_outp.write(writer)?;
 433                         }
 434                 }
 435                 Ok(())
 436         }
 437 }
 438
 439 impl Readable for PackageSolvingData {
 440         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 441                 let byte = <u8 as Readable>::read(reader)?;
 442                 let solving_data = match byte {
 443                         0 => {
 444                                 PackageSolvingData::RevokedOutput(Readable::read(reader)?)
 445                         },
 446                         1 => {
 447                                 PackageSolvingData::RevokedHTLCOutput(Readable::read(reader)?)
 448                         },
 449                         2 => {
 450                                 PackageSolvingData::CounterpartyOfferedHTLCOutput(Readable::read(reader)?)
 451                         },
 452                         3 => {
 453                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(Readable::read(reader)?)
 454                         },
 455                         4 => {
 456                                 PackageSolvingData::HolderHTLCOutput(Readable::read(reader)?)
 457                         },
 458                         5 => {
 459                                 PackageSolvingData::HolderFundingOutput(Readable::read(reader)?)
 460                         }
 461                         _ => return Err(DecodeError::UnknownVersion)
 462                 };
 463                 Ok(solving_data)
 464         }
 465 }
 466
 467 /// A malleable package might be aggregated with other packages to save on fees.
 468 /// A untractable package has been counter-signed and aggregable will break cached counterparty
 469 /// signatures.
 470 #[derive(Clone, PartialEq)]
 471 pub(crate) enum PackageMalleability {
 472         Malleable,
 473         Untractable,
 474 }
 475
 476 /// A structure to describe a package content that is generated by ChannelMonitor and
 477 /// used by OnchainTxHandler to generate and broadcast transactions settling onchain claims.
 478 ///
 479 /// A package is defined as one or more transactions claiming onchain outputs in reaction
 480 /// to confirmation of a channel transaction. Those packages might be aggregated to save on
 481 /// fees, if satisfaction of outputs's witnessScript let's us do so.
 482 ///
 483 /// As packages are time-sensitive, we fee-bump and rebroadcast them at scheduled intervals.
 484 /// Failing to confirm a package translate as a loss of funds for the user.
 485 #[derive(Clone, PartialEq)]
 486 pub struct PackageTemplate {
 487         // List of onchain outputs and solving data to generate satisfying witnesses.
 488         inputs: Vec<(BitcoinOutPoint, PackageSolvingData)>,
 489         // Packages are deemed as malleable if we have local knwoledge of at least one set of
 490         // private keys yielding a satisfying witnesses. Malleability implies that we can aggregate
 491         // packages among them to save on fees or rely on RBF to bump their feerates.
 492         // Untractable packages have been counter-signed and thus imply that we can't aggregate
 493         // them without breaking signatures. Fee-bumping strategy will also rely on CPFP.
 494         malleability: PackageMalleability,
 495         // Block height after which the earlier-output belonging to this package is mature for a
 496         // competing claim by the counterparty. As our chain tip becomes nearer from the timelock,
 497         // the fee-bumping frequency will increase. See `OnchainTxHandler::get_height_timer`.
 498         soonest_conf_deadline: u32,
 499         // Determines if this package can be aggregated.
 500         // Timelocked outputs belonging to the same transaction might have differing
 501         // satisfying heights. Picking up the later height among the output set would be a valid
 502         // aggregable strategy but it comes with at least 2 trade-offs :
 503         // * earlier-output fund are going to take longer to come back
 504         // * CLTV delta backing up a corresponding HTLC on an upstream channel could be swallowed
 505         // by the requirement of the later-output part of the set
 506         // For now, we mark such timelocked outputs as non-aggregable, though we might introduce
 507         // smarter aggregable strategy in the future.
 508         aggregable: bool,
 509         // Cache of package feerate committed at previous (re)broadcast. If bumping resources
 510         // (either claimed output value or external utxo), it will keep increasing until holder
 511         // or counterparty successful claim.
 512         feerate_previous: u64,
 513         // Cache of next height at which fee-bumping and rebroadcast will be attempted. In
 514         // the future, we might abstract it to an observed mempool fluctuation.
 515         height_timer: Option<u32>,
 516         // Confirmation height of the claimed outputs set transaction. In case of reorg reaching
 517         // it, we wipe out and forget the package.
 518         height_original: u32,
 519 }
 520
 521 impl PackageTemplate {
 522         pub(crate) fn is_malleable(&self) -> bool {
 523                 self.malleability == PackageMalleability::Malleable
 524         }
 525         pub(crate) fn timelock(&self) -> u32 {
 526                 self.soonest_conf_deadline
 527         }
 528         pub(crate) fn aggregable(&self) -> bool {
 529                 self.aggregable
 530         }
 531         pub(crate) fn set_feerate(&mut self, new_feerate: u64) {
 532                 self.feerate_previous = new_feerate;
 533         }
 534         pub(crate) fn timer(&self) -> Option<u32> {
 535                 if let Some(ref timer) = self.height_timer {
 536                         return Some(*timer);
 537                 }
 538                 None
 539         }
 540         pub(crate) fn set_timer(&mut self, new_timer: Option<u32>) {
 541                 self.height_timer = new_timer;
 542         }
 543         pub(crate) fn outpoints(&self) -> Vec<&BitcoinOutPoint> {
 544                 self.inputs.iter().map(|(o, _)| o).collect()
 545         }
 546         pub(crate) fn split_package(&mut self, split_outp: &BitcoinOutPoint) -> Option<PackageTemplate> {
 547                 match self.malleability {
 548                         PackageMalleability::Malleable => {
 549                                 let mut split_package = None;
 550                                 let timelock = self.soonest_conf_deadline;
 551                                 let aggregable = self.aggregable;
 552                                 let feerate_previous = self.feerate_previous;
 553                                 let height_timer = self.height_timer;
 554                                 let height_original = self.height_original;
 555                                 self.inputs.retain(|outp| {
 556                                         if *split_outp == outp.0 {
 557                                                 split_package = Some(PackageTemplate {
 558                                                         inputs: vec![(outp.0, outp.1.clone())],
 559                                                         malleability: PackageMalleability::Malleable,
 560                                                         soonest_conf_deadline: timelock,
 561                                                         aggregable,
 562                                                         feerate_previous,
 563                                                         height_timer,
 564                                                         height_original,
 565                                                 });
 566                                                 return false;
 567                                         }
 568                                         return true;
 569                                 });
 570                                 return split_package;
 571                         },
 572                         _ => {
 573                                 // Note, we may try to split on remote transaction for
 574                                 // which we don't have a competing one (HTLC-Success before
 575                                 // timelock expiration). This explain we don't panic!
 576                                 // We should refactor OnchainTxHandler::block_connected to
 577                                 // only test equality on competing claims.
 578                                 return None;
 579                         }
 580                 }
 581         }
 582         pub(crate) fn merge_package(&mut self, mut merge_from: PackageTemplate) {
 583                 assert_eq!(self.height_original, merge_from.height_original);
 584                 if self.malleability == PackageMalleability::Untractable || merge_from.malleability == PackageMalleability::Untractable {
 585                         panic!("Merging template on untractable packages");
 586                 }
 587                 if !self.aggregable || !merge_from.aggregable {
 588                         panic!("Merging non aggregatable packages");
 589                 }
 590                 if let Some((_, lead_input)) = self.inputs.first() {
 591                         for (_, v) in merge_from.inputs.iter() {
 592                                 if !lead_input.is_compatible(v) { panic!("Merging outputs from differing types !"); }
 593                         }
 594                 } else { panic!("Merging template on an empty package"); }
 595                 for (k, v) in merge_from.inputs.drain(..) {
 596                         self.inputs.push((k, v));
 597                 }
 598                 //TODO: verify coverage and sanity?
 599                 if self.soonest_conf_deadline > merge_from.soonest_conf_deadline {
 600                         self.soonest_conf_deadline = merge_from.soonest_conf_deadline;
 601                 }
 602                 if self.feerate_previous > merge_from.feerate_previous {
 603                         self.feerate_previous = merge_from.feerate_previous;
 604                 }
 605                 self.height_timer = cmp::min(self.height_timer, merge_from.height_timer);
 606         }
 607         /// Gets the amount of all outptus being spent by this package, only valid for malleable
 608         /// packages.
 609         fn package_amount(&self) -> u64 {
 610                 let mut amounts = 0;
 611                 for (_, outp) in self.inputs.iter() {
 612                         amounts += outp.amount();
 613                 }
 614                 amounts
 615         }
 616         pub(crate) fn package_timelock(&self) -> u32 {
 617                 self.inputs.iter().map(|(_, outp)| outp.absolute_tx_timelock(self.height_original))
 618                         .max().expect("There must always be at least one output to spend in a PackageTemplate")
 619         }
 620         pub(crate) fn package_weight(&self, destination_script: &Script) -> usize {
 621                 let mut inputs_weight = 0;
 622                 let mut witnesses_weight = 2; // count segwit flags
 623                 for (_, outp) in self.inputs.iter() {
 624                         // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes
 625                         inputs_weight += 41 * WITNESS_SCALE_FACTOR;
 626                         witnesses_weight += outp.weight();
 627                 }
 628                 // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes
 629                 let transaction_weight = 10 * WITNESS_SCALE_FACTOR;
 630                 // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()`
 631                 let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR;
 632                 inputs_weight + witnesses_weight + transaction_weight + output_weight
 633         }
 634         pub(crate) fn finalize_package<L: Deref, Signer: Sign>(&self, onchain_handler: &mut OnchainTxHandler<Signer>, value: u64, destination_script: Script, logger: &L) -> Option<Transaction>
 635                 where L::Target: Logger,
 636         {
 637                 match self.malleability {
 638                         PackageMalleability::Malleable => {
 639                                 let mut bumped_tx = Transaction {
 640                                         version: 2,
 641                                         lock_time: 0,
 642                                         input: vec![],
 643                                         output: vec![TxOut {
 644                                                 script_pubkey: destination_script,
 645                                                 value,
 646                                         }],
 647                                 };
 648                                 for (outpoint, _) in self.inputs.iter() {
 649                                         bumped_tx.input.push(TxIn {
 650                                                 previous_output: *outpoint,
 651                                                 script_sig: Script::new(),
 652                                                 sequence: 0xfffffffd,
 653                                                 witness: Vec::new(),
 654                                         });
 655                                 }
 656                                 for (i, (outpoint, out)) in self.inputs.iter().enumerate() {
 657                                         log_trace!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
 658                                         if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; }
 659                                 }
 660                                 log_trace!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid());
 661                                 return Some(bumped_tx);
 662                         },
 663                         PackageMalleability::Untractable => {
 664                                 debug_assert_eq!(value, 0, "value is ignored for non-malleable packages, should be zero to ensure callsites are correct");
 665                                 if let Some((outpoint, outp)) = self.inputs.first() {
 666                                         if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) {
 667                                                 log_trace!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
 668                                                 log_trace!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid());
 669                                                 return Some(final_tx);
 670                                         }
 671                                         return None;
 672                                 } else { panic!("API Error: Package must not be inputs empty"); }
 673                         },
 674                 }
 675         }
 676         /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
 677         /// 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
 678         /// height that once reached we should generate a new bumped "version" of the claim tx to be sure that we safely claim outputs before
 679         /// that our counterparty can do so. If timelock expires soon, height timer is going to be scaled down in consequence to increase
 680         /// frequency of the bump and so increase our bets of success.
 681         pub(crate) fn get_height_timer(&self, current_height: u32) -> u32 {
 682                 if self.soonest_conf_deadline <= current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL {
 683                         return current_height + HIGH_FREQUENCY_BUMP_INTERVAL
 684                 } else if self.soonest_conf_deadline - current_height <= LOW_FREQUENCY_BUMP_INTERVAL {
 685                         return current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL
 686                 }
 687                 current_height + LOW_FREQUENCY_BUMP_INTERVAL
 688         }
 689         /// Returns value in satoshis to be included as package outgoing output amount and feerate with which package finalization should be done.
 690         pub(crate) fn compute_package_output<F: Deref, L: Deref>(&self, predicted_weight: usize, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
 691                 where F::Target: FeeEstimator,
 692                       L::Target: Logger,
 693         {
 694                 debug_assert!(self.malleability == PackageMalleability::Malleable, "The package output is fixed for non-malleable packages");
 695                 let input_amounts = self.package_amount();
 696                 // If old feerate is 0, first iteration of this claim, use normal fee calculation
 697                 if self.feerate_previous != 0 {
 698                         if let Some((new_fee, feerate)) = feerate_bump(predicted_weight, input_amounts, self.feerate_previous, fee_estimator, logger) {
 699                                 // If new computed fee is superior at the whole claimable amount burn all in fees
 700                                 if new_fee > input_amounts {
 701                                         return Some((0, feerate));
 702                                 } else {
 703                                         return Some((input_amounts - new_fee, feerate));
 704                                 }
 705                         }
 706                 } else {
 707                         if let Some((new_fee, feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
 708                                 return Some((input_amounts - new_fee, feerate));
 709                         }
 710                 }
 711                 None
 712         }
 713         pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, aggregable: bool, height_original: u32) -> Self {
 714                 let malleability = match input_solving_data {
 715                         PackageSolvingData::RevokedOutput(..) => { PackageMalleability::Malleable },
 716                         PackageSolvingData::RevokedHTLCOutput(..) => { PackageMalleability::Malleable },
 717                         PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { PackageMalleability::Malleable },
 718                         PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { PackageMalleability::Malleable },
 719                         PackageSolvingData::HolderHTLCOutput(..) => { PackageMalleability::Untractable },
 720                         PackageSolvingData::HolderFundingOutput(..) => { PackageMalleability::Untractable },
 721                 };
 722                 let mut inputs = Vec::with_capacity(1);
 723                 inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data));
 724                 PackageTemplate {
 725                         inputs,
 726                         malleability,
 727                         soonest_conf_deadline,
 728                         aggregable,
 729                         feerate_previous: 0,
 730                         height_timer: None,
 731                         height_original,
 732                 }
 733         }
 734 }
 735
 736 impl Writeable for PackageTemplate {
 737         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 738                 writer.write_all(&byte_utils::be64_to_array(self.inputs.len() as u64))?;
 739                 for (ref outpoint, ref rev_outp) in self.inputs.iter() {
 740                         outpoint.write(writer)?;
 741                         rev_outp.write(writer)?;
 742                 }
 743                 write_tlv_fields!(writer, {
 744                         (0, self.soonest_conf_deadline),
 745                         (2, self.feerate_previous),
 746                         (4, self.height_original),
 747                 }, { (6, self.height_timer) });
 748                 Ok(())
 749         }
 750 }
 751
 752 impl Readable for PackageTemplate {
 753         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 754                 let inputs_count = <u64 as Readable>::read(reader)?;
 755                 let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128));
 756                 for _ in 0..inputs_count {
 757                         let outpoint = Readable::read(reader)?;
 758                         let rev_outp = Readable::read(reader)?;
 759                         inputs.push((outpoint, rev_outp));
 760                 }
 761                 let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() {
 762                         match lead_input {
 763                                 PackageSolvingData::RevokedOutput(..) => { (PackageMalleability::Malleable, true) },
 764                                 PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
 765                                 PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
 766                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) },
 767                                 PackageSolvingData::HolderHTLCOutput(..) => { (PackageMalleability::Untractable, false) },
 768                                 PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) },
 769                         }
 770                 } else { return Err(DecodeError::InvalidValue); };
 771                 let mut soonest_conf_deadline = 0;
 772                 let mut feerate_previous = 0;
 773                 let mut height_timer = None;
 774                 let mut height_original = 0;
 775                 read_tlv_fields!(reader, {
 776                         (0, soonest_conf_deadline),
 777                         (2, feerate_previous),
 778                         (4, height_original)
 779                 }, { (6, height_timer) });
 780                 Ok(PackageTemplate {
 781                         inputs,
 782                         malleability,
 783                         soonest_conf_deadline,
 784                         aggregable,
 785                         feerate_previous,
 786                         height_timer,
 787                         height_original,
 788                 })
 789         }
 790 }
 791
 792 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
 793 /// weight. We start with the highest priority feerate returned by the node's fee estimator then
 794 /// fall-back to lower priorities until we have enough value available to suck from.
 795 ///
 796 /// If the proposed fee is less than the available spent output's values, we return the proposed
 797 /// fee and the corresponding updated feerate. If the proposed fee is equal or more than the
 798 /// available spent output's values, we return nothing
 799 fn compute_fee_from_spent_amounts<F: Deref, L: Deref>(input_amounts: u64, predicted_weight: usize, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
 800         where F::Target: FeeEstimator,
 801               L::Target: Logger,
 802 {
 803         let mut updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64;
 804         let mut fee = updated_feerate * (predicted_weight as u64) / 1000;
 805         if input_amounts <= fee {
 806                 updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64;
 807                 fee = updated_feerate * (predicted_weight as u64) / 1000;
 808                 if input_amounts <= fee {
 809                         updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u64;
 810                         fee = updated_feerate * (predicted_weight as u64) / 1000;
 811                         if input_amounts <= fee {
 812                                 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)",
 813                                         fee, input_amounts);
 814                                 None
 815                         } else {
 816                                 log_warn!(logger, "Used low priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
 817                                         input_amounts);
 818                                 Some((fee, updated_feerate))
 819                         }
 820                 } else {
 821                         log_warn!(logger, "Used medium priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
 822                                 input_amounts);
 823                         Some((fee, updated_feerate))
 824                 }
 825         } else {
 826                 Some((fee, updated_feerate))
 827         }
 828 }
 829
 830 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
 831 /// weight. If feerates proposed by the fee-estimator have been increasing since last fee-bumping
 832 /// attempt, use them. Otherwise, blindly bump the feerate by 25% of the previous feerate. We also
 833 /// verify that those bumping heuristics respect BIP125 rules 3) and 4) and if required adjust
 834 /// the new fee to meet the RBF policy requirement.
 835 fn feerate_bump<F: Deref, L: Deref>(predicted_weight: usize, input_amounts: u64, previous_feerate: u64, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
 836         where F::Target: FeeEstimator,
 837               L::Target: Logger,
 838 {
 839         // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
 840         let new_fee = if let Some((new_fee, _)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
 841                 let updated_feerate = new_fee / (predicted_weight as u64 * 1000);
 842                 if updated_feerate > previous_feerate {
 843                         new_fee
 844                 } else {
 845                         // ...else just increase the previous feerate by 25% (because that's a nice number)
 846                         let new_fee = previous_feerate * (predicted_weight as u64) / 750;
 847                         if input_amounts <= new_fee {
 848                                 log_trace!(logger, "Can't 25% bump new claiming tx, amount {} is too small", input_amounts);
 849                                 return None;
 850                         }
 851                         new_fee
 852                 }
 853         } else {
 854                 log_trace!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", input_amounts);
 855                 return None;
 856         };
 857
 858         let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
 859         let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * (predicted_weight as u64) / 1000;
 860         // BIP 125 Opt-in Full Replace-by-Fee Signaling
 861         //      * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
 862         //      * 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.
 863         let new_fee = if new_fee < previous_fee + min_relay_fee {
 864                 new_fee + previous_fee + min_relay_fee - new_fee
 865         } else {
 866                 new_fee
 867         };
 868         Some((new_fee, new_fee * 1000 / (predicted_weight as u64)))
 869 }
 870
 871 #[cfg(test)]
 872 mod tests {
 873         use chain::package::{CounterpartyReceivedHTLCOutput, HolderHTLCOutput, PackageTemplate, PackageSolvingData, RevokedOutput, WEIGHT_REVOKED_OUTPUT};
 874         use chain::Txid;
 875         use ln::chan_utils::HTLCOutputInCommitment;
 876         use ln::{PaymentPreimage, PaymentHash};
 877
 878         use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
 879         use bitcoin::blockdata::script::Script;
 880         use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
 881
 882         use bitcoin::hashes::hex::FromHex;
 883
 884         use bitcoin::secp256k1::key::{PublicKey,SecretKey};
 885         use bitcoin::secp256k1::Secp256k1;
 886
 887         macro_rules! dumb_revk_output {
 888                 ($secp_ctx: expr) => {
 889                         {
 890                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
 891                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
 892                                 PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0))
 893                         }
 894                 }
 895         }
 896
 897         macro_rules! dumb_counterparty_output {
 898                 ($secp_ctx: expr, $amt: expr) => {
 899                         {
 900                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
 901                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
 902                                 let hash = PaymentHash([1; 32]);
 903                                 let htlc = HTLCOutputInCommitment { offered: true, amount_msat: $amt, cltv_expiry: 0, payment_hash: hash, transaction_output_index: None };
 904                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(dumb_point, dumb_point, dumb_point, htlc))
 905                         }
 906                 }
 907         }
 908
 909         macro_rules! dumb_htlc_output {
 910                 () => {
 911                         {
 912                                 let preimage = PaymentPreimage([2;32]);
 913                                 PackageSolvingData::HolderHTLCOutput(HolderHTLCOutput::build_accepted(preimage, 0))
 914                         }
 915                 }
 916         }
 917
 918         #[test]
 919         #[should_panic]
 920         fn test_package_differing_heights() {
 921                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 922                 let secp_ctx = Secp256k1::new();
 923                 let revk_outp = dumb_revk_output!(secp_ctx);
 924
 925                 let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 926                 let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 200);
 927                 package_one_hundred.merge_package(package_two_hundred);
 928         }
 929
 930         #[test]
 931         #[should_panic]
 932         fn test_package_untractable_merge_to() {
 933                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 934                 let secp_ctx = Secp256k1::new();
 935                 let revk_outp = dumb_revk_output!(secp_ctx);
 936                 let htlc_outp = dumb_htlc_output!();
 937
 938                 let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 939                 let malleable_package = PackageTemplate::build_package(txid, 1, htlc_outp.clone(), 1000, true, 100);
 940                 untractable_package.merge_package(malleable_package);
 941         }
 942
 943         #[test]
 944         #[should_panic]
 945         fn test_package_untractable_merge_from() {
 946                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 947                 let secp_ctx = Secp256k1::new();
 948                 let htlc_outp = dumb_htlc_output!();
 949                 let revk_outp = dumb_revk_output!(secp_ctx);
 950
 951                 let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, true, 100);
 952                 let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
 953                 malleable_package.merge_package(untractable_package);
 954         }
 955
 956         #[test]
 957         #[should_panic]
 958         fn test_package_noaggregation_to() {
 959                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 960                 let secp_ctx = Secp256k1::new();
 961                 let revk_outp = dumb_revk_output!(secp_ctx);
 962
 963                 let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, false, 100);
 964                 let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
 965                 noaggregation_package.merge_package(aggregation_package);
 966         }
 967
 968         #[test]
 969         #[should_panic]
 970         fn test_package_noaggregation_from() {
 971                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 972                 let secp_ctx = Secp256k1::new();
 973                 let revk_outp = dumb_revk_output!(secp_ctx);
 974
 975                 let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 976                 let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, false, 100);
 977                 aggregation_package.merge_package(noaggregation_package);
 978         }
 979
 980         #[test]
 981         #[should_panic]
 982         fn test_package_empty() {
 983                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 984                 let secp_ctx = Secp256k1::new();
 985                 let revk_outp = dumb_revk_output!(secp_ctx);
 986
 987                 let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 988                 empty_package.inputs = vec![];
 989                 let package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
 990                 empty_package.merge_package(package);
 991         }
 992
 993         #[test]
 994         #[should_panic]
 995         fn test_package_differing_categories() {
 996                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 997                 let secp_ctx = Secp256k1::new();
 998                 let revk_outp = dumb_revk_output!(secp_ctx);
 999                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0);
1000
1001                 let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100);
1002                 let counterparty_package = PackageTemplate::build_package(txid, 1, counterparty_outp, 1000, true, 100);
1003                 revoked_package.merge_package(counterparty_package);
1004         }
1005
1006         #[test]
1007         fn test_package_split_malleable() {
1008                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1009                 let secp_ctx = Secp256k1::new();
1010                 let revk_outp_one = dumb_revk_output!(secp_ctx);
1011                 let revk_outp_two = dumb_revk_output!(secp_ctx);
1012                 let revk_outp_three = dumb_revk_output!(secp_ctx);
1013
1014                 let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, true, 100);
1015                 let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, true, 100);
1016                 let package_three = PackageTemplate::build_package(txid, 2, revk_outp_three, 1000, true, 100);
1017
1018                 package_one.merge_package(package_two);
1019                 package_one.merge_package(package_three);
1020                 assert_eq!(package_one.outpoints().len(), 3);
1021
1022                 if let Some(split_package) = package_one.split_package(&BitcoinOutPoint { txid, vout: 1 }) {
1023                         // Packages attributes should be identical
1024                         assert!(split_package.is_malleable());
1025                         assert_eq!(split_package.soonest_conf_deadline, package_one.soonest_conf_deadline);
1026                         assert_eq!(split_package.aggregable, package_one.aggregable);
1027                         assert_eq!(split_package.feerate_previous, package_one.feerate_previous);
1028                         assert_eq!(split_package.height_timer, package_one.height_timer);
1029                         assert_eq!(split_package.height_original, package_one.height_original);
1030                 } else { panic!(); }
1031                 assert_eq!(package_one.outpoints().len(), 2);
1032         }
1033
1034         #[test]
1035         fn test_package_split_untractable() {
1036                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1037                 let htlc_outp_one = dumb_htlc_output!();
1038
1039                 let mut package_one = PackageTemplate::build_package(txid, 0, htlc_outp_one, 1000, true, 100);
1040                 let ret_split = package_one.split_package(&BitcoinOutPoint { txid, vout: 0});
1041                 assert!(ret_split.is_none());
1042         }
1043
1044         #[test]
1045         fn test_package_timer() {
1046                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1047                 let secp_ctx = Secp256k1::new();
1048                 let revk_outp = dumb_revk_output!(secp_ctx);
1049
1050                 let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100);
1051                 let timer_none = package.timer();
1052                 assert!(timer_none.is_none());
1053                 package.set_timer(Some(100));
1054                 if let Some(timer_some) = package.timer() {
1055                         assert_eq!(timer_some, 100);
1056                 } else { panic!() }
1057         }
1058
1059         #[test]
1060         fn test_package_amounts() {
1061                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1062                 let secp_ctx = Secp256k1::new();
1063                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000);
1064
1065                 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, true, 100);
1066                 assert_eq!(package.package_amount(), 1000);
1067         }
1068
1069         #[test]
1070         fn test_package_weight() {
1071                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1072                 let secp_ctx = Secp256k1::new();
1073                 let revk_outp = dumb_revk_output!(secp_ctx);
1074
1075                 let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, true, 100);
1076                 // (nVersion (4) + nLocktime (4) + count_tx_in (1) + prevout (36) + sequence (4) + script_length (1) + count_tx_out (1) + value (8) + var_int (1)) * WITNESS_SCALE_FACTOR
1077                 // + witness marker (2) + WEIGHT_REVOKED_OUTPUT
1078                 assert_eq!(package.package_weight(&Script::new()), (4 + 4 + 1 + 36 + 4 + 1 + 1 + 8 + 1) * WITNESS_SCALE_FACTOR + 2 + WEIGHT_REVOKED_OUTPUT as usize);
1079         }
1080 }