From c9bd7b3f2de03491b0f428fd9bf9db66c42f239a Mon Sep 17 00:00:00 2001 From: Antoine Riard Date: Fri, 7 May 2021 19:36:50 -0400 Subject: [PATCH] Introduce PackageTemplae, a replacement of InputMaterial PackageTemplate aims to replace InputMaterial, introducing a clean interface to manipulate a wide range of claim types without OnchainTxHandler aware of special content of each. This is used in next commits. --- lightning/src/ln/chan_utils.rs | 2 +- lightning/src/ln/package.rs | 706 ++++++++++++++++++++++++++++++++- 2 files changed, 706 insertions(+), 2 deletions(-) diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs index 9b44d119..28b5a9f8 100644 --- a/lightning/src/ln/chan_utils.rs +++ b/lightning/src/ln/chan_utils.rs @@ -40,7 +40,7 @@ use core::ops::Deref; use chain; // Maximum size of a serialized HTLCOutputInCommitment -const HTLC_OUTPUT_IN_COMMITMENT_SIZE: usize = 1 + 8 + 4 + 32 + 5; +pub(crate) const HTLC_OUTPUT_IN_COMMITMENT_SIZE: usize = 1 + 8 + 4 + 32 + 5; pub(crate) const MAX_HTLCS: u16 = 483; diff --git a/lightning/src/ln/package.rs b/lightning/src/ln/package.rs index c0d735a0..078f0f63 100644 --- a/lightning/src/ln/package.rs +++ b/lightning/src/ln/package.rs @@ -1,8 +1,712 @@ -//! Utilities for computing witnesses weight and feerate computation for onchain operation +// This file is Copyright its original authors, visible in version control +// history. +// +// This file is licensed under the Apache License, Version 2.0 or the MIT license +// , at your option. +// You may not use this file except in accordance with one or both of these +// licenses. +//! Various utilities to assemble claimable outpoints in package of one or more transactions. Those +//! packages are attached metadata, guiding their aggregable or fee-bumping re-schedule. This file +//! also includes witness weight computation and fee computation methods. + +use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR; +use bitcoin::blockdata::transaction::{TxOut,TxIn, Transaction, SigHashType}; +use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint; +use bitcoin::blockdata::script::Script; + +use bitcoin::hash_types::Txid; + +use bitcoin::secp256k1::key::{SecretKey,PublicKey}; + +use ln::PaymentPreimage; +use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment, HTLC_OUTPUT_IN_COMMITMENT_SIZE}; +use ln::chan_utils; use ln::msgs::DecodeError; +use ln::onchaintx::OnchainTxHandler; +use chain::keysinterface::Sign; +use util::byte_utils; +use util::logger::Logger; use util::ser::{Readable, Writer, Writeable}; +use std::cmp; +use std::mem; +use std::ops::Deref; + +const MAX_ALLOC_SIZE: usize = 64*1024; + + +// number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script +pub(crate) const WEIGHT_REVOKED_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 133; +// number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script +pub(crate) const WEIGHT_REVOKED_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 139; +// number_of_witness_elements + sig_length + counterpartyhtlc_sig + preimage_length + preimage + witness_script_length + witness_script +pub(crate) const WEIGHT_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 32 + 1 + 133; +// number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script +pub(crate) const WEIGHT_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 139; +// number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script +pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77; + +/// A struct to describe a revoked output and corresponding information to generate a solving +/// witness spending a commitment `to_local` output or a second-stage HTLC transaction output. +/// +/// CSV and pubkeys are used as part of a witnessScript redeeming a balance output, amount is used +/// as part of the signature hash and revocation secret to generate a satisfying witness. +#[derive(Clone, PartialEq)] +pub(crate) struct RevokedOutput { + per_commitment_point: PublicKey, + counterparty_delayed_payment_base_key: PublicKey, + counterparty_htlc_base_key: PublicKey, + per_commitment_key: SecretKey, + weight: u64, + amount: u64, + on_counterparty_tx_csv: u16, +} + +impl RevokedOutput { + 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 { + RevokedOutput { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + per_commitment_key, + weight: WEIGHT_REVOKED_OUTPUT, + amount, + on_counterparty_tx_csv + } + } +} + +impl_writeable!(RevokedOutput, 33*3 + 32 + 8 + 8 + 2, { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + per_commitment_key, + weight, + amount, + on_counterparty_tx_csv +}); + +/// A struct to describe a revoked offered output and corresponding information to generate a +/// solving witness. +/// +/// HTLCOuputInCommitment (hash timelock, direction) and pubkeys are used to generate a suitable +/// witnessScript. +/// +/// CSV is used as part of a witnessScript redeeming a balance output, amount is used as part +/// of the signature hash and revocation secret to generate a satisfying witness. +#[derive(Clone, PartialEq)] +pub(crate) struct RevokedHTLCOutput { + per_commitment_point: PublicKey, + counterparty_delayed_payment_base_key: PublicKey, + counterparty_htlc_base_key: PublicKey, + per_commitment_key: SecretKey, + weight: u64, + amount: u64, + htlc: HTLCOutputInCommitment, +} + +impl RevokedHTLCOutput { + 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 { + let weight = if htlc.offered { WEIGHT_REVOKED_OFFERED_HTLC } else { WEIGHT_REVOKED_RECEIVED_HTLC }; + RevokedHTLCOutput { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + per_commitment_key, + weight, + amount, + htlc + } + } +} + +impl_writeable!(RevokedHTLCOutput, 33*3 + 32 + 8 + 8 + HTLC_OUTPUT_IN_COMMITMENT_SIZE, { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + per_commitment_key, + weight, + amount, + htlc +}); + +/// A struct to describe a HTLC output on a counterparty commitment transaction. +/// +/// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable +/// witnessScript. +/// +/// The preimage is used as part of the witness. +#[derive(Clone, PartialEq)] +pub(crate) struct CounterpartyOfferedHTLCOutput { + per_commitment_point: PublicKey, + counterparty_delayed_payment_base_key: PublicKey, + counterparty_htlc_base_key: PublicKey, + preimage: PaymentPreimage, + htlc: HTLCOutputInCommitment +} + +impl CounterpartyOfferedHTLCOutput { + pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, preimage: PaymentPreimage, htlc: HTLCOutputInCommitment) -> Self { + CounterpartyOfferedHTLCOutput { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + preimage, + htlc + } + } +} + +impl_writeable!(CounterpartyOfferedHTLCOutput, 33*3 + 32 + HTLC_OUTPUT_IN_COMMITMENT_SIZE, { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + preimage, + htlc +}); + +/// A struct to describe a HTLC output on a counterparty commitment transaction. +/// +/// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable +/// witnessScript. +#[derive(Clone, PartialEq)] +pub(crate) struct CounterpartyReceivedHTLCOutput { + per_commitment_point: PublicKey, + counterparty_delayed_payment_base_key: PublicKey, + counterparty_htlc_base_key: PublicKey, + htlc: HTLCOutputInCommitment +} + +impl CounterpartyReceivedHTLCOutput { + pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, htlc: HTLCOutputInCommitment) -> Self { + CounterpartyReceivedHTLCOutput { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + htlc + } + } +} + +impl_writeable!(CounterpartyReceivedHTLCOutput, 33*3 + HTLC_OUTPUT_IN_COMMITMENT_SIZE, { + per_commitment_point, + counterparty_delayed_payment_base_key, + counterparty_htlc_base_key, + htlc +}); + +/// A struct to describe a HTLC output on holder commitment transaction. +/// +/// Either offered or received, the amount is always used as part of the bip143 sighash. +/// Preimage is only included as part of the witness in former case. +#[derive(Clone, PartialEq)] +pub(crate) struct HolderHTLCOutput { + preimage: Option, + amount: u64, +} + +impl HolderHTLCOutput { + pub(crate) fn build(preimage: Option, amount: u64) -> Self { + HolderHTLCOutput { + preimage, + amount + } + } +} + +impl_writeable!(HolderHTLCOutput, 0, { + preimage, + amount +}); + +/// A struct to describe the channel output on the funding transaction. +/// +/// witnessScript is used as part of the witness redeeming the funding utxo. +#[derive(Clone, PartialEq)] +pub(crate) struct HolderFundingOutput { + funding_redeemscript: Script, +} + +impl HolderFundingOutput { + pub(crate) fn build(funding_redeemscript: Script) -> Self { + HolderFundingOutput { + funding_redeemscript, + } + } +} + +impl_writeable!(HolderFundingOutput, 0, { + funding_redeemscript +}); + +/// A wrapper encapsulating all in-protocol differing outputs types. +/// +/// The generic API offers access to an outputs common attributes or allow transformation such as +/// finalizing an input claiming the output. +#[derive(Clone, PartialEq)] +pub(crate) enum PackageSolvingData { + RevokedOutput(RevokedOutput), + RevokedHTLCOutput(RevokedHTLCOutput), + CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput), + CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput), + HolderHTLCOutput(HolderHTLCOutput), + HolderFundingOutput(HolderFundingOutput), +} + +impl PackageSolvingData { + fn amount(&self) -> u64 { + let amt = match self { + PackageSolvingData::RevokedOutput(ref outp) => { outp.amount }, + PackageSolvingData::RevokedHTLCOutput(ref outp) => { outp.amount }, + PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => { outp.htlc.amount_msat / 1000 }, + PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => { outp.htlc.amount_msat / 1000 }, + // Note: Currently, amounts of holder outputs spending witnesses aren't used + // as we can't malleate spending package to increase their feerate. This + // should change with the remaining anchor output patchset. + PackageSolvingData::HolderHTLCOutput(..) => { 0 }, + PackageSolvingData::HolderFundingOutput(..) => { 0 }, + }; + amt + } + fn weight(&self) -> usize { + let weight = match self { + PackageSolvingData::RevokedOutput(ref outp) => { outp.weight as usize }, + PackageSolvingData::RevokedHTLCOutput(ref outp) => { outp.weight as usize }, + PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { WEIGHT_OFFERED_HTLC as usize }, + PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { WEIGHT_RECEIVED_HTLC as usize }, + // Note: Currently, weights of holder outputs spending witnesses aren't used + // as we can't malleate spending package to increase their feerate. This + // should change with the remaining anchor output patchset. + PackageSolvingData::HolderHTLCOutput(..) => { debug_assert!(false); 0 }, + PackageSolvingData::HolderFundingOutput(..) => { debug_assert!(false); 0 }, + }; + weight + } + fn is_compatible(&self, input: &PackageSolvingData) -> bool { + match self { + PackageSolvingData::RevokedOutput(..) => { + match input { + PackageSolvingData::RevokedHTLCOutput(..) => { true }, + PackageSolvingData::RevokedOutput(..) => { true }, + _ => { false } + } + }, + PackageSolvingData::RevokedHTLCOutput(..) => { + match input { + PackageSolvingData::RevokedOutput(..) => { true }, + PackageSolvingData::RevokedHTLCOutput(..) => { true }, + _ => { false } + } + }, + _ => { mem::discriminant(self) == mem::discriminant(&input) } + } + } + fn finalize_input(&self, bumped_tx: &mut Transaction, i: usize, onchain_handler: &mut OnchainTxHandler) -> bool { + match self { + PackageSolvingData::RevokedOutput(ref outp) => { + 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) { + let witness_script = chan_utils::get_revokeable_redeemscript(&chan_keys.revocation_key, outp.on_counterparty_tx_csv, &chan_keys.broadcaster_delayed_payment_key); + //TODO: should we panic on signer failure ? + if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_output(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &onchain_handler.secp_ctx) { + bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); + bumped_tx.input[i].witness[0].push(SigHashType::All as u8); + bumped_tx.input[i].witness.push(vec!(1)); + bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); + } else { return false; } + } + }, + PackageSolvingData::RevokedHTLCOutput(ref outp) => { + 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) { + 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); + //TODO: should we panic on signer failure ? + 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) { + bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); + bumped_tx.input[i].witness[0].push(SigHashType::All as u8); + bumped_tx.input[i].witness.push(chan_keys.revocation_key.clone().serialize().to_vec()); + bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); + } else { return false; } + } + }, + PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => { + 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) { + 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); + + 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) { + bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); + bumped_tx.input[i].witness[0].push(SigHashType::All as u8); + bumped_tx.input[i].witness.push(outp.preimage.0.to_vec()); + bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); + } + } + }, + PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => { + 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) { + 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); + + 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 + 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) { + bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); + bumped_tx.input[i].witness[0].push(SigHashType::All as u8); + // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay. + bumped_tx.input[i].witness.push(vec![]); + bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); + } + } + }, + _ => { panic!("API Error!"); } + } + true + } + fn get_finalized_tx(&self, outpoint: &BitcoinOutPoint, onchain_handler: &mut OnchainTxHandler) -> Option { + match self { + PackageSolvingData::HolderHTLCOutput(ref outp) => { return onchain_handler.get_fully_signed_htlc_tx(outpoint, &outp.preimage); } + PackageSolvingData::HolderFundingOutput(ref outp) => { return Some(onchain_handler.get_fully_signed_holder_tx(&outp.funding_redeemscript)); } + _ => { panic!("API Error!"); } + } + } +} + +impl Writeable for PackageSolvingData { + fn write(&self, writer: &mut W) -> Result<(), ::std::io::Error> { + match self { + PackageSolvingData::RevokedOutput(ref revoked_outp) => { + 0u8.write(writer)?; + revoked_outp.write(writer)?; + }, + PackageSolvingData::RevokedHTLCOutput(ref revoked_outp) => { + 1u8.write(writer)?; + revoked_outp.write(writer)?; + }, + PackageSolvingData::CounterpartyOfferedHTLCOutput(ref counterparty_outp) => { + 2u8.write(writer)?; + counterparty_outp.write(writer)?; + }, + PackageSolvingData::CounterpartyReceivedHTLCOutput(ref counterparty_outp) => { + 3u8.write(writer)?; + counterparty_outp.write(writer)?; + }, + PackageSolvingData::HolderHTLCOutput(ref holder_outp) => { + 4u8.write(writer)?; + holder_outp.write(writer)?; + }, + PackageSolvingData::HolderFundingOutput(ref funding_outp) => { + 5u8.write(writer)?; + funding_outp.write(writer)?; + } + } + Ok(()) + } +} + +impl Readable for PackageSolvingData { + fn read(reader: &mut R) -> Result { + let byte = ::read(reader)?; + let solving_data = match byte { + 0 => { + PackageSolvingData::RevokedOutput(Readable::read(reader)?) + }, + 1 => { + PackageSolvingData::RevokedHTLCOutput(Readable::read(reader)?) + }, + 2 => { + PackageSolvingData::CounterpartyOfferedHTLCOutput(Readable::read(reader)?) + }, + 3 => { + PackageSolvingData::CounterpartyReceivedHTLCOutput(Readable::read(reader)?) + }, + 4 => { + PackageSolvingData::HolderHTLCOutput(Readable::read(reader)?) + }, + 5 => { + PackageSolvingData::HolderFundingOutput(Readable::read(reader)?) + } + _ => return Err(DecodeError::UnknownVersion) + }; + Ok(solving_data) + } +} + +/// A malleable package might be aggregated with other packages to save on fees. +/// A untractable package has been counter-signed and aggregable will break cached counterparty +/// signatures. +#[derive(Clone, PartialEq)] +pub(crate) enum PackageMalleability { + Malleable, + Untractable, +} + +/// A structure to describe a package content that is generated by ChannelMonitor and +/// used by OnchainTxHandler to generate and broadcast transactions settling onchain claims. +/// +/// A package is defined as one or more transactions claiming onchain outputs in reaction +/// to confirmation of a channel transaction. Those packages might be aggregated to save on +/// fees, if satisfaction of outputs's witnessScript let's us do so. +/// +/// As packages are time-sensitive, we fee-bump and rebroadcast them at scheduled intervals. +/// Failing to confirm a package translate as a loss of funds for the user. +#[derive(Clone, PartialEq)] +pub struct PackageTemplate { + // List of onchain outputs and solving data to generate satisfying witnesses. + inputs: Vec<(BitcoinOutPoint, PackageSolvingData)>, + // Packages are deemed as malleable if we have local knwoledge of at least one set of + // private keys yielding a satisfying witnesses. Malleability implies that we can aggregate + // packages among them to save on fees or rely on RBF to bump their feerates. + // Untractable packages have been counter-signed and thus imply that we can't aggregate + // them without breaking signatures. Fee-bumping strategy will also rely on CPFP. + malleability: PackageMalleability, + // Block height after which the earlier-output belonging to this package is mature for a + // competing claim by the counterparty. As our chain tip becomes nearer from the timelock, + // the fee-bumping frequency will increase. See `OnchainTxHandler::get_height_timer`. + soonest_conf_deadline: u32, + // Determines if this package can be aggregated. + // Timelocked outputs belonging to the same transaction might have differing + // satisfying heights. Picking up the later height among the output set would be a valid + // aggregable strategy but it comes with at least 2 trade-offs : + // * earlier-output fund are going to take longer to come back + // * CLTV delta backing up a corresponding HTLC on an upstream channel could be swallowed + // by the requirement of the later-output part of the set + // For now, we mark such timelocked outputs as non-aggregable, though we might introduce + // smarter aggregable strategy in the future. + aggregable: bool, + // Cache of package feerate committed at previous (re)broadcast. If bumping resources + // (either claimed output value or external utxo), it will keep increasing until holder + // or counterparty successful claim. + feerate_previous: u64, + // Cache of next height at which fee-bumping and rebroadcast will be attempted. In + // the future, we might abstract it to an observed mempool fluctuation. + height_timer: Option, + // Confirmation height of the claimed outputs set transaction. In case of reorg reaching + // it, we wipe out and forget the package. + height_original: u32, +} + +impl PackageTemplate { + pub(crate) fn is_malleable(&self) -> bool { + self.malleability == PackageMalleability::Malleable + } + pub(crate) fn timelock(&self) -> u32 { + self.soonest_conf_deadline + } + pub(crate) fn aggregable(&self) -> bool { + self.aggregable + } + pub(crate) fn feerate(&self) -> u64 { + self.feerate_previous + } + pub(crate) fn set_feerate(&mut self, new_feerate: u64) { + self.feerate_previous = new_feerate; + } + pub(crate) fn timer(&self) -> Option { + if let Some(ref timer) = self.height_timer { + return Some(*timer); + } + None + } + pub(crate) fn set_timer(&mut self, new_timer: Option) { + self.height_timer = new_timer; + } + pub(crate) fn outpoints(&self) -> Vec<&BitcoinOutPoint> { + self.inputs.iter().map(|(o, _)| o).collect() + } + pub(crate) fn split_package(&mut self, split_outp: &BitcoinOutPoint) -> Option { + match self.malleability { + PackageMalleability::Malleable => { + let mut split_package = None; + let timelock = self.soonest_conf_deadline; + let aggregable = self.aggregable; + let feerate_previous = self.feerate_previous; + let height_timer = self.height_timer; + let height_original = self.height_original; + self.inputs.retain(|outp| { + if *split_outp == outp.0 { + split_package = Some(PackageTemplate { + inputs: vec![(outp.0, outp.1.clone())], + malleability: PackageMalleability::Malleable, + soonest_conf_deadline: timelock, + aggregable, + feerate_previous, + height_timer, + height_original, + }); + return false; + } + return true; + }); + return split_package; + }, + _ => { + // Note, we may try to split on remote transaction for + // which we don't have a competing one (HTLC-Success before + // timelock expiration). This explain we don't panic! + // We should refactor OnchainTxHandler::block_connected to + // only test equality on competing claims. + return None; + } + } + } + pub(crate) fn merge_package(&mut self, mut merge_from: PackageTemplate) { + assert_eq!(self.height_original, merge_from.height_original); + if self.malleability == PackageMalleability::Untractable || merge_from.malleability == PackageMalleability::Untractable { + panic!("Merging template on untractable packages"); + } + if !self.aggregable || !merge_from.aggregable { + panic!("Merging non aggregatable packages"); + } + if let Some((_, lead_input)) = self.inputs.first() { + for (_, v) in merge_from.inputs.iter() { + if !lead_input.is_compatible(v) { panic!("Merging outputs from differing types !"); } + } + } else { panic!("Merging template on an empty package"); } + for (k, v) in merge_from.inputs.drain(..) { + self.inputs.push((k, v)); + } + //TODO: verify coverage and sanity? + if self.soonest_conf_deadline > merge_from.soonest_conf_deadline { + self.soonest_conf_deadline = merge_from.soonest_conf_deadline; + } + if self.feerate_previous > merge_from.feerate_previous { + self.feerate_previous = merge_from.feerate_previous; + } + self.height_timer = cmp::min(self.height_timer, merge_from.height_timer); + } + pub(crate) fn package_amount(&self) -> u64 { + let mut amounts = 0; + for (_, outp) in self.inputs.iter() { + amounts += outp.amount(); + } + amounts + } + pub(crate) fn package_weight(&self, destination_script: &Script) -> usize { + let mut inputs_weight = 0; + let mut witnesses_weight = 2; // count segwit flags + for (_, outp) in self.inputs.iter() { + // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes + inputs_weight += 41 * WITNESS_SCALE_FACTOR; + witnesses_weight += outp.weight(); + } + // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes + let transaction_weight = 10 * WITNESS_SCALE_FACTOR; + // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()` + let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR; + inputs_weight + witnesses_weight + transaction_weight + output_weight + } + pub(crate) fn finalize_package(&self, onchain_handler: &mut OnchainTxHandler, value: u64, destination_script: Script, logger: &L) -> Option + where L::Target: Logger, + { + match self.malleability { + PackageMalleability::Malleable => { + let mut bumped_tx = Transaction { + version: 2, + lock_time: 0, + input: vec![], + output: vec![TxOut { + script_pubkey: destination_script, + value, + }], + }; + for (outpoint, _) in self.inputs.iter() { + bumped_tx.input.push(TxIn { + previous_output: *outpoint, + script_sig: Script::new(), + sequence: 0xfffffffd, + witness: Vec::new(), + }); + } + for (i, (outpoint, out)) in self.inputs.iter().enumerate() { + log_trace!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout); + if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; } + } + log_trace!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid()); + return Some(bumped_tx); + }, + PackageMalleability::Untractable => { + if let Some((outpoint, outp)) = self.inputs.first() { + if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) { + log_trace!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout); + log_trace!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid()); + return Some(final_tx); + } + return None; + } else { panic!("API Error: Package must not be inputs empty"); } + }, + } + } + pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, aggregable: bool, height_original: u32) -> Self { + let malleability = match input_solving_data { + PackageSolvingData::RevokedOutput(..) => { PackageMalleability::Malleable }, + PackageSolvingData::RevokedHTLCOutput(..) => { PackageMalleability::Malleable }, + PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { PackageMalleability::Malleable }, + PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { PackageMalleability::Malleable }, + PackageSolvingData::HolderHTLCOutput(..) => { PackageMalleability::Untractable }, + PackageSolvingData::HolderFundingOutput(..) => { PackageMalleability::Untractable }, + }; + let mut inputs = Vec::with_capacity(1); + inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data)); + PackageTemplate { + inputs, + malleability, + soonest_conf_deadline, + aggregable, + feerate_previous: 0, + height_timer: None, + height_original, + } + } +} + +impl Writeable for PackageTemplate { + fn write(&self, writer: &mut W) -> Result<(), ::std::io::Error> { + writer.write_all(&byte_utils::be64_to_array(self.inputs.len() as u64))?; + for (ref outpoint, ref rev_outp) in self.inputs.iter() { + outpoint.write(writer)?; + rev_outp.write(writer)?; + } + self.soonest_conf_deadline.write(writer)?; + self.feerate_previous.write(writer)?; + self.height_timer.write(writer)?; + self.height_original.write(writer)?; + Ok(()) + } +} + +impl Readable for PackageTemplate { + fn read(reader: &mut R) -> Result { + let inputs_count = ::read(reader)?; + let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128)); + for _ in 0..inputs_count { + let outpoint = Readable::read(reader)?; + let rev_outp = Readable::read(reader)?; + inputs.push((outpoint, rev_outp)); + } + let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() { + match lead_input { + PackageSolvingData::RevokedOutput(..) => { (PackageMalleability::Malleable, true) }, + PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) }, + PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) }, + PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) }, + PackageSolvingData::HolderHTLCOutput(..) => { (PackageMalleability::Untractable, false) }, + PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) }, + } + } else { return Err(DecodeError::InvalidValue); }; + let soonest_conf_deadline = Readable::read(reader)?; + let feerate_previous = Readable::read(reader)?; + let height_timer = Readable::read(reader)?; + let height_original = Readable::read(reader)?; + Ok(PackageTemplate { + inputs, + malleability, + soonest_conf_deadline, + aggregable, + feerate_previous, + height_timer, + height_original, + }) + } +} + +/// Utilities for computing witnesses weight and feerate computation for onchain operation #[derive(PartialEq, Clone, Copy)] pub(crate) enum InputDescriptors { RevokedOfferedHTLC, -- 2.30.2