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