_ 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(..) => { 0 },
 278                         PackageSolvingData::HolderFundingOutput(..) => { 0 },
 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(..) => { debug_assert!(false); 0 },
 292                         PackageSolvingData::HolderFundingOutput(..) => { debug_assert!(false); 0 },
 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         pub(crate) fn package_amount(&self) -> u64 {
 581                 let mut amounts = 0;
 582                 for (_, outp) in self.inputs.iter() {
 583                         amounts += outp.amount();
 584                 }
 585                 amounts
 586         }
 587         pub(crate) fn package_weight(&self, destination_script: &Script) -> usize {
 588                 let mut inputs_weight = 0;
 589                 let mut witnesses_weight = 2; // count segwit flags
 590                 for (_, outp) in self.inputs.iter() {
 591                         // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes
 592                         inputs_weight += 41 * WITNESS_SCALE_FACTOR;
 593                         witnesses_weight += outp.weight();
 594                 }
 595                 // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes
 596                 let transaction_weight = 10 * WITNESS_SCALE_FACTOR;
 597                 // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()`
 598                 let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR;
 599                 inputs_weight + witnesses_weight + transaction_weight + output_weight
 600         }
 601         pub(crate) fn finalize_package<L: Deref, Signer: Sign>(&self, onchain_handler: &mut OnchainTxHandler<Signer>, value: u64, destination_script: Script, logger: &L) -> Option<Transaction>
 602                 where L::Target: Logger,
 603         {
 604                 match self.malleability {
 605                         PackageMalleability::Malleable => {
 606                                 let mut bumped_tx = Transaction {
 607                                         version: 2,
 608                                         lock_time: 0,
 609                                         input: vec![],
 610                                         output: vec![TxOut {
 611                                                 script_pubkey: destination_script,
 612                                                 value,
 613                                         }],
 614                                 };
 615                                 for (outpoint, _) in self.inputs.iter() {
 616                                         bumped_tx.input.push(TxIn {
 617                                                 previous_output: *outpoint,
 618                                                 script_sig: Script::new(),
 619                                                 sequence: 0xfffffffd,
 620                                                 witness: Vec::new(),
 621                                         });
 622                                 }
 623                                 for (i, (outpoint, out)) in self.inputs.iter().enumerate() {
 624                                         log_trace!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
 625                                         if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; }
 626                                 }
 627                                 log_trace!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid());
 628                                 return Some(bumped_tx);
 629                         },
 630                         PackageMalleability::Untractable => {
 631                                 if let Some((outpoint, outp)) = self.inputs.first() {
 632                                         if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) {
 633                                                 log_trace!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
 634                                                 log_trace!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid());
 635                                                 return Some(final_tx);
 636                                         }
 637                                         return None;
 638                                 } else { panic!("API Error: Package must not be inputs empty"); }
 639                         },
 640                 }
 641         }
 642         /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
 643         /// 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
 644         /// height that once reached we should generate a new bumped "version" of the claim tx to be sure that we safely claim outputs before
 645         /// that our counterparty can do so. If timelock expires soon, height timer is going to be scaled down in consequence to increase
 646         /// frequency of the bump and so increase our bets of success.
 647         pub(crate) fn get_height_timer(&self, current_height: u32) -> u32 {
 648                 if self.soonest_conf_deadline <= current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL {
 649                         return current_height + HIGH_FREQUENCY_BUMP_INTERVAL
 650                 } else if self.soonest_conf_deadline - current_height <= LOW_FREQUENCY_BUMP_INTERVAL {
 651                         return current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL
 652                 }
 653                 current_height + LOW_FREQUENCY_BUMP_INTERVAL
 654         }
 655         /// Returns value in satoshis to be included as package outgoing output amount and feerate with which package finalization should be done.
 656         pub(crate) fn compute_package_output<F: Deref, L: Deref>(&self, predicted_weight: usize, input_amounts: u64, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
 657                 where F::Target: FeeEstimator,
 658                       L::Target: Logger,
 659         {
 660                 // If old feerate is 0, first iteration of this claim, use normal fee calculation
 661                 if self.feerate_previous != 0 {
 662                         if let Some((new_fee, feerate)) = feerate_bump(predicted_weight, input_amounts, self.feerate_previous, fee_estimator, logger) {
 663                                 // If new computed fee is superior at the whole claimable amount burn all in fees
 664                                 if new_fee > input_amounts {
 665                                         return Some((0, feerate));
 666                                 } else {
 667                                         return Some((input_amounts - new_fee, feerate));
 668                                 }
 669                         }
 670                 } else {
 671                         if let Some((new_fee, feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
 672                                 return Some((input_amounts - new_fee, feerate));
 673                         }
 674                 }
 675                 None
 676         }
 677         pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, aggregable: bool, height_original: u32) -> Self {
 678                 let malleability = match input_solving_data {
 679                         PackageSolvingData::RevokedOutput(..) => { PackageMalleability::Malleable },
 680                         PackageSolvingData::RevokedHTLCOutput(..) => { PackageMalleability::Malleable },
 681                         PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { PackageMalleability::Malleable },
 682                         PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { PackageMalleability::Malleable },
 683                         PackageSolvingData::HolderHTLCOutput(..) => { PackageMalleability::Untractable },
 684                         PackageSolvingData::HolderFundingOutput(..) => { PackageMalleability::Untractable },
 685                 };
 686                 let mut inputs = Vec::with_capacity(1);
 687                 inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data));
 688                 PackageTemplate {
 689                         inputs,
 690                         malleability,
 691                         soonest_conf_deadline,
 692                         aggregable,
 693                         feerate_previous: 0,
 694                         height_timer: None,
 695                         height_original,
 696                 }
 697         }
 698 }
 699
 700 impl Writeable for PackageTemplate {
 701         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 702                 writer.write_all(&byte_utils::be64_to_array(self.inputs.len() as u64))?;
 703                 for (ref outpoint, ref rev_outp) in self.inputs.iter() {
 704                         outpoint.write(writer)?;
 705                         rev_outp.write(writer)?;
 706                 }
 707                 write_tlv_fields!(writer, {
 708                         (0, self.soonest_conf_deadline),
 709                         (2, self.feerate_previous),
 710                         (4, self.height_original),
 711                 }, { (6, self.height_timer) });
 712                 Ok(())
 713         }
 714 }
 715
 716 impl Readable for PackageTemplate {
 717         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 718                 let inputs_count = <u64 as Readable>::read(reader)?;
 719                 let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128));
 720                 for _ in 0..inputs_count {
 721                         let outpoint = Readable::read(reader)?;
 722                         let rev_outp = Readable::read(reader)?;
 723                         inputs.push((outpoint, rev_outp));
 724                 }
 725                 let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() {
 726                         match lead_input {
 727                                 PackageSolvingData::RevokedOutput(..) => { (PackageMalleability::Malleable, true) },
 728                                 PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
 729                                 PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
 730                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) },
 731                                 PackageSolvingData::HolderHTLCOutput(..) => { (PackageMalleability::Untractable, false) },
 732                                 PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) },
 733                         }
 734                 } else { return Err(DecodeError::InvalidValue); };
 735                 let mut soonest_conf_deadline = 0;
 736                 let mut feerate_previous = 0;
 737                 let mut height_timer = None;
 738                 let mut height_original = 0;
 739                 read_tlv_fields!(reader, {
 740                         (0, soonest_conf_deadline),
 741                         (2, feerate_previous),
 742                         (4, height_original)
 743                 }, { (6, height_timer) });
 744                 Ok(PackageTemplate {
 745                         inputs,
 746                         malleability,
 747                         soonest_conf_deadline,
 748                         aggregable,
 749                         feerate_previous,
 750                         height_timer,
 751                         height_original,
 752                 })
 753         }
 754 }
 755
 756 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
 757 /// weight. We start with the highest priority feerate returned by the node's fee estimator then
 758 /// fall-back to lower priorities until we have enough value available to suck from.
 759 ///
 760 /// If the proposed fee is less than the available spent output's values, we return the proposed
 761 /// fee and the corresponding updated feerate. If the proposed fee is equal or more than the
 762 /// available spent output's values, we return nothing
 763 fn compute_fee_from_spent_amounts<F: Deref, L: Deref>(input_amounts: u64, predicted_weight: usize, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
 764         where F::Target: FeeEstimator,
 765               L::Target: Logger,
 766 {
 767         let mut updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64;
 768         let mut fee = updated_feerate * (predicted_weight as u64) / 1000;
 769         if input_amounts <= fee {
 770                 updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64;
 771                 fee = updated_feerate * (predicted_weight as u64) / 1000;
 772                 if input_amounts <= fee {
 773                         updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u64;
 774                         fee = updated_feerate * (predicted_weight as u64) / 1000;
 775                         if input_amounts <= fee {
 776                                 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)",
 777                                         fee, input_amounts);
 778                                 None
 779                         } else {
 780                                 log_warn!(logger, "Used low priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
 781                                         input_amounts);
 782                                 Some((fee, updated_feerate))
 783                         }
 784                 } else {
 785                         log_warn!(logger, "Used medium 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                 Some((fee, updated_feerate))
 791         }
 792 }
 793
 794 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
 795 /// weight. If feerates proposed by the fee-estimator have been increasing since last fee-bumping
 796 /// attempt, use them. Otherwise, blindly bump the feerate by 25% of the previous feerate. We also
 797 /// verify that those bumping heuristics respect BIP125 rules 3) and 4) and if required adjust
 798 /// the new fee to meet the RBF policy requirement.
 799 fn feerate_bump<F: Deref, L: Deref>(predicted_weight: usize, input_amounts: u64, previous_feerate: u64, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
 800         where F::Target: FeeEstimator,
 801               L::Target: Logger,
 802 {
 803         // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
 804         let new_fee = if let Some((new_fee, _)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
 805                 let updated_feerate = new_fee / (predicted_weight as u64 * 1000);
 806                 if updated_feerate > previous_feerate {
 807                         new_fee
 808                 } else {
 809                         // ...else just increase the previous feerate by 25% (because that's a nice number)
 810                         let new_fee = previous_feerate * (predicted_weight as u64) / 750;
 811                         if input_amounts <= new_fee {
 812                                 log_trace!(logger, "Can't 25% bump new claiming tx, amount {} is too small", input_amounts);
 813                                 return None;
 814                         }
 815                         new_fee
 816                 }
 817         } else {
 818                 log_trace!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", input_amounts);
 819                 return None;
 820         };
 821
 822         let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
 823         let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * (predicted_weight as u64) / 1000;
 824         // BIP 125 Opt-in Full Replace-by-Fee Signaling
 825         //      * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
 826         //      * 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.
 827         let new_fee = if new_fee < previous_fee + min_relay_fee {
 828                 new_fee + previous_fee + min_relay_fee - new_fee
 829         } else {
 830                 new_fee
 831         };
 832         Some((new_fee, new_fee * 1000 / (predicted_weight as u64)))
 833 }
 834
 835 #[cfg(test)]
 836 mod tests {
 837         use chain::package::{CounterpartyReceivedHTLCOutput, HolderHTLCOutput, PackageTemplate, PackageSolvingData, RevokedOutput, WEIGHT_REVOKED_OUTPUT};
 838         use chain::Txid;
 839         use ln::chan_utils::HTLCOutputInCommitment;
 840         use ln::{PaymentPreimage, PaymentHash};
 841
 842         use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
 843         use bitcoin::blockdata::script::Script;
 844         use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
 845
 846         use bitcoin::hashes::hex::FromHex;
 847
 848         use bitcoin::secp256k1::key::{PublicKey,SecretKey};
 849         use bitcoin::secp256k1::Secp256k1;
 850
 851         macro_rules! dumb_revk_output {
 852                 ($secp_ctx: expr) => {
 853                         {
 854                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
 855                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
 856                                 PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0))
 857                         }
 858                 }
 859         }
 860
 861         macro_rules! dumb_counterparty_output {
 862                 ($secp_ctx: expr, $amt: expr) => {
 863                         {
 864                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
 865                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
 866                                 let hash = PaymentHash([1; 32]);
 867                                 let htlc = HTLCOutputInCommitment { offered: true, amount_msat: $amt, cltv_expiry: 0, payment_hash: hash, transaction_output_index: None };
 868                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(dumb_point, dumb_point, dumb_point, htlc))
 869                         }
 870                 }
 871         }
 872
 873         macro_rules! dumb_htlc_output {
 874                 () => {
 875                         {
 876                                 let preimage = PaymentPreimage([2;32]);
 877                                 PackageSolvingData::HolderHTLCOutput(HolderHTLCOutput::build(Some(preimage), 0))
 878                         }
 879                 }
 880         }
 881
 882         #[test]
 883         #[should_panic]
 884         fn test_package_differing_heights() {
 885                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 886                 let secp_ctx = Secp256k1::new();
 887                 let revk_outp = dumb_revk_output!(secp_ctx);
 888
 889                 let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 890                 let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 200);
 891                 package_one_hundred.merge_package(package_two_hundred);
 892         }
 893
 894         #[test]
 895         #[should_panic]
 896         fn test_package_untractable_merge_to() {
 897                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 898                 let secp_ctx = Secp256k1::new();
 899                 let revk_outp = dumb_revk_output!(secp_ctx);
 900                 let htlc_outp = dumb_htlc_output!();
 901
 902                 let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 903                 let malleable_package = PackageTemplate::build_package(txid, 1, htlc_outp.clone(), 1000, true, 100);
 904                 untractable_package.merge_package(malleable_package);
 905         }
 906
 907         #[test]
 908         #[should_panic]
 909         fn test_package_untractable_merge_from() {
 910                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 911                 let secp_ctx = Secp256k1::new();
 912                 let htlc_outp = dumb_htlc_output!();
 913                 let revk_outp = dumb_revk_output!(secp_ctx);
 914
 915                 let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, true, 100);
 916                 let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
 917                 malleable_package.merge_package(untractable_package);
 918         }
 919
 920         #[test]
 921         #[should_panic]
 922         fn test_package_noaggregation_to() {
 923                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 924                 let secp_ctx = Secp256k1::new();
 925                 let revk_outp = dumb_revk_output!(secp_ctx);
 926
 927                 let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, false, 100);
 928                 let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
 929                 noaggregation_package.merge_package(aggregation_package);
 930         }
 931
 932         #[test]
 933         #[should_panic]
 934         fn test_package_noaggregation_from() {
 935                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 936                 let secp_ctx = Secp256k1::new();
 937                 let revk_outp = dumb_revk_output!(secp_ctx);
 938
 939                 let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 940                 let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, false, 100);
 941                 aggregation_package.merge_package(noaggregation_package);
 942         }
 943
 944         #[test]
 945         #[should_panic]
 946         fn test_package_empty() {
 947                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 948                 let secp_ctx = Secp256k1::new();
 949                 let revk_outp = dumb_revk_output!(secp_ctx);
 950
 951                 let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
 952                 empty_package.inputs = vec![];
 953                 let package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
 954                 empty_package.merge_package(package);
 955         }
 956
 957         #[test]
 958         #[should_panic]
 959         fn test_package_differing_categories() {
 960                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 961                 let secp_ctx = Secp256k1::new();
 962                 let revk_outp = dumb_revk_output!(secp_ctx);
 963                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0);
 964
 965                 let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100);
 966                 let counterparty_package = PackageTemplate::build_package(txid, 1, counterparty_outp, 1000, true, 100);
 967                 revoked_package.merge_package(counterparty_package);
 968         }
 969
 970         #[test]
 971         fn test_package_split_malleable() {
 972                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
 973                 let secp_ctx = Secp256k1::new();
 974                 let revk_outp_one = dumb_revk_output!(secp_ctx);
 975                 let revk_outp_two = dumb_revk_output!(secp_ctx);
 976                 let revk_outp_three = dumb_revk_output!(secp_ctx);
 977
 978                 let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, true, 100);
 979                 let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, true, 100);
 980                 let package_three = PackageTemplate::build_package(txid, 2, revk_outp_three, 1000, true, 100);
 981
 982                 package_one.merge_package(package_two);
 983                 package_one.merge_package(package_three);
 984                 assert_eq!(package_one.outpoints().len(), 3);
 985
 986                 if let Some(split_package) = package_one.split_package(&BitcoinOutPoint { txid, vout: 1 }) {
 987                         // Packages attributes should be identical
 988                         assert!(split_package.is_malleable());
 989                         assert_eq!(split_package.soonest_conf_deadline, package_one.soonest_conf_deadline);
 990                         assert_eq!(split_package.aggregable, package_one.aggregable);
 991                         assert_eq!(split_package.feerate_previous, package_one.feerate_previous);
 992                         assert_eq!(split_package.height_timer, package_one.height_timer);
 993                         assert_eq!(split_package.height_original, package_one.height_original);
 994                 } else { panic!(); }
 995                 assert_eq!(package_one.outpoints().len(), 2);
 996         }
 997
 998         #[test]
 999         fn test_package_split_untractable() {
1000                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1001                 let htlc_outp_one = dumb_htlc_output!();
1002
1003                 let mut package_one = PackageTemplate::build_package(txid, 0, htlc_outp_one, 1000, true, 100);
1004                 let ret_split = package_one.split_package(&BitcoinOutPoint { txid, vout: 0});
1005                 assert!(ret_split.is_none());
1006         }
1007
1008         #[test]
1009         fn test_package_timer() {
1010                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1011                 let secp_ctx = Secp256k1::new();
1012                 let revk_outp = dumb_revk_output!(secp_ctx);
1013
1014                 let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100);
1015                 let timer_none = package.timer();
1016                 assert!(timer_none.is_none());
1017                 package.set_timer(Some(100));
1018                 if let Some(timer_some) = package.timer() {
1019                         assert_eq!(timer_some, 100);
1020                 } else { panic!() }
1021         }
1022
1023         #[test]
1024         fn test_package_amounts() {
1025                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1026                 let secp_ctx = Secp256k1::new();
1027                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000);
1028
1029                 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, true, 100);
1030                 assert_eq!(package.package_amount(), 1000);
1031         }
1032
1033         #[test]
1034         fn test_package_weight() {
1035                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1036                 let secp_ctx = Secp256k1::new();
1037                 let revk_outp = dumb_revk_output!(secp_ctx);
1038
1039                 let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, true, 100);
1040                 // (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
1041                 // + witness marker (2) + WEIGHT_REVOKED_OUTPUT
1042                 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);
1043         }
1044 }