From a3c32d603a66a0bb78363807f7757822b87db637 Mon Sep 17 00:00:00 2001 From: Antoine Riard Date: Tue, 8 Nov 2022 19:12:22 -0500 Subject: [PATCH] Anchor: do not aggregate claim of revoked output See https://github.com/lightning/bolts/pull/803 This protect the justice claim of counterparty revoked output. As otherwise if the all the revoked outputs claims are batched in a single transaction, low-feerate HTLCs transactions can delay our honest justice claim transaction until BREAKDOWN_TIMEOUT expires. --- lightning/src/chain/channelmonitor.rs | 9 ++-- lightning/src/chain/package.rs | 74 ++++++++++++--------------- 2 files changed, 40 insertions(+), 43 deletions(-) diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs index e3f6f428eb3..75894234c5b 100644 --- a/lightning/src/chain/channelmonitor.rs +++ b/lightning/src/chain/channelmonitor.rs @@ -2614,8 +2614,10 @@ impl ChannelMonitorImpl { // First, process non-htlc outputs (to_holder & to_counterparty) for (idx, outp) in tx.output.iter().enumerate() { if outp.script_pubkey == revokeable_p2wsh { - let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, outp.value, self.counterparty_commitment_params.on_counterparty_tx_csv); - let justice_package = PackageTemplate::build_package(commitment_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, true, height); + let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, outp.value, self.counterparty_commitment_params.on_counterparty_tx_csv, self.onchain_tx_handler.opt_anchors()); + // Post-anchor, aggregation of outputs of different types is unsafe. See https://github.com/lightning/bolts/pull/803. + let aggregation = if self.onchain_tx_handler.opt_anchors() { false } else { true }; + let justice_package = PackageTemplate::build_package(commitment_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, aggregation, height); claimable_outpoints.push(justice_package); to_counterparty_output_info = Some((idx.try_into().expect("Txn can't have more than 2^32 outputs"), outp.value)); @@ -2798,7 +2800,8 @@ impl ChannelMonitorImpl { let revk_outp = RevokedOutput::build( per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, - tx.output[idx].value, self.counterparty_commitment_params.on_counterparty_tx_csv + tx.output[idx].value, self.counterparty_commitment_params.on_counterparty_tx_csv, + false ); let justice_package = PackageTemplate::build_package( htlc_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), diff --git a/lightning/src/chain/package.rs b/lightning/src/chain/package.rs index e66092222d8..69f45addce2 100644 --- a/lightning/src/chain/package.rs +++ b/lightning/src/chain/package.rs @@ -98,10 +98,11 @@ pub(crate) struct RevokedOutput { weight: u64, amount: u64, on_counterparty_tx_csv: u16, + is_counterparty_balance_on_anchors: Option<()>, } 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 { + 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, is_counterparty_balance_on_anchors: bool) -> Self { RevokedOutput { per_commitment_point, counterparty_delayed_payment_base_key, @@ -109,7 +110,8 @@ impl RevokedOutput { per_commitment_key, weight: WEIGHT_REVOKED_OUTPUT, amount, - on_counterparty_tx_csv + on_counterparty_tx_csv, + is_counterparty_balance_on_anchors: if is_counterparty_balance_on_anchors { Some(()) } else { None } } } } @@ -122,6 +124,7 @@ impl_writeable_tlv_based!(RevokedOutput, { (8, weight, required), (10, amount, required), (12, on_counterparty_tx_csv, required), + (14, is_counterparty_balance_on_anchors, option) }); /// A struct to describe a revoked offered output and corresponding information to generate a @@ -827,18 +830,7 @@ impl PackageTemplate { } 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(ref outp) => if outp.opt_anchors() { - PackageMalleability::Malleable - } else { - PackageMalleability::Untractable - }, - PackageSolvingData::HolderFundingOutput(..) => PackageMalleability::Untractable, - }; + let (malleability, aggregable) = Self::map_output_type_flags(&input_solving_data); let mut inputs = Vec::with_capacity(1); inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data)); PackageTemplate { @@ -851,6 +843,19 @@ impl PackageTemplate { height_original, } } + + fn map_output_type_flags(input_solving_data: &PackageSolvingData) -> (PackageMalleability, bool) { + let (malleability, aggregable) = match input_solving_data { + PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: Some(()), .. }) => { (PackageMalleability::Malleable, false) }, + PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: None, .. }) => { (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) }, + }; + (malleability, aggregable) + } } impl Writeable for PackageTemplate { @@ -880,18 +885,7 @@ impl Readable for PackageTemplate { 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(ref outp) => if outp.opt_anchors() { - (PackageMalleability::Malleable, outp.preimage.is_some()) - } else { - (PackageMalleability::Untractable, false) - }, - PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) }, - } + Self::map_output_type_flags(&lead_input) } else { return Err(DecodeError::InvalidValue); }; let mut soonest_conf_deadline = 0; let mut feerate_previous = 0; @@ -1029,11 +1023,11 @@ mod tests { use bitcoin::secp256k1::Secp256k1; macro_rules! dumb_revk_output { - ($secp_ctx: expr) => { + ($secp_ctx: expr, $is_counterparty_balance_on_anchors: expr) => { { let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap(); let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar); - PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0)) + PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0, $is_counterparty_balance_on_anchors)) } } } @@ -1077,7 +1071,7 @@ mod tests { fn test_package_differing_heights() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100); let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 200); @@ -1089,7 +1083,7 @@ mod tests { fn test_package_untractable_merge_to() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let htlc_outp = dumb_htlc_output!(); let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100); @@ -1103,7 +1097,7 @@ mod tests { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); let htlc_outp = dumb_htlc_output!(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, true, 100); let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100); @@ -1115,7 +1109,7 @@ mod tests { fn test_package_noaggregation_to() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, true); let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, false, 100); let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100); @@ -1127,7 +1121,7 @@ mod tests { fn test_package_noaggregation_from() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, true); let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100); let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, false, 100); @@ -1139,7 +1133,7 @@ mod tests { fn test_package_empty() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100); empty_package.inputs = vec![]; @@ -1152,7 +1146,7 @@ mod tests { fn test_package_differing_categories() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0, false); let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100); @@ -1164,9 +1158,9 @@ mod tests { fn test_package_split_malleable() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp_one = dumb_revk_output!(secp_ctx); - let revk_outp_two = dumb_revk_output!(secp_ctx); - let revk_outp_three = dumb_revk_output!(secp_ctx); + let revk_outp_one = dumb_revk_output!(secp_ctx, false); + let revk_outp_two = dumb_revk_output!(secp_ctx, false); + let revk_outp_three = dumb_revk_output!(secp_ctx, false); let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, true, 100); let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, true, 100); @@ -1202,7 +1196,7 @@ mod tests { fn test_package_timer() { let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap(); let secp_ctx = Secp256k1::new(); - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100); assert_eq!(package.timer(), 100); @@ -1229,7 +1223,7 @@ mod tests { let weight_sans_output = (4 + 4 + 1 + 36 + 4 + 1 + 1 + 8 + 1) * WITNESS_SCALE_FACTOR + 2; { - let revk_outp = dumb_revk_output!(secp_ctx); + let revk_outp = dumb_revk_output!(secp_ctx, false); let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, true, 100); assert_eq!(package.package_weight(&Script::new()), weight_sans_output + WEIGHT_REVOKED_OUTPUT as usize); }