X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchan_utils.rs;h=7fc817995fbdba393809c73c264e6e010a5e27c0;hb=be7b82b5b8670c27fccba03975a1b4fa34fe5760;hp=a8c9dcc826e540d91e4020c67789df23e30297a4;hpb=a257906743d528c32c862b053b652d4b728aa990;p=rust-lightning diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs index a8c9dcc8..7fc81799 100644 --- a/lightning/src/ln/chan_utils.rs +++ b/lightning/src/ln/chan_utils.rs @@ -14,6 +14,7 @@ use bitcoin::blockdata::script::{Script,Builder}; use bitcoin::blockdata::opcodes; use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, EcdsaSighashType}; use bitcoin::util::sighash; +use bitcoin::util::address::Payload; use bitcoin::hashes::{Hash, HashEngine}; use bitcoin::hashes::sha256::Hash as Sha256; @@ -25,11 +26,11 @@ use crate::ln::msgs::DecodeError; use crate::util::ser::{Readable, Writeable, Writer}; use crate::util::{byte_utils, transaction_utils}; -use bitcoin::hash_types::WPubkeyHash; use bitcoin::secp256k1::{SecretKey, PublicKey, Scalar}; use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature, Message}; use bitcoin::secp256k1::Error as SecpError; use bitcoin::{PackedLockTime, secp256k1, Sequence, Witness}; +use bitcoin::PublicKey as BitcoinPublicKey; use crate::io; use crate::prelude::*; @@ -41,13 +42,20 @@ use core::ops::Deref; use crate::chain; use crate::util::crypto::sign; -pub(crate) const MAX_HTLCS: u16 = 483; -pub(crate) const OFFERED_HTLC_SCRIPT_WEIGHT: usize = 133; -pub(crate) const OFFERED_HTLC_SCRIPT_WEIGHT_ANCHORS: usize = 136; -// The weight of `accepted_htlc_script` can vary in function of its CLTV argument value. We define a -// range that encompasses both its non-anchors and anchors variants. +/// Maximum number of one-way in-flight HTLC (protocol-level value). +pub const MAX_HTLCS: u16 = 483; +/// The weight of a BIP141 witnessScript for a BOLT3's "offered HTLC output" on a commitment transaction, non-anchor variant. +pub const OFFERED_HTLC_SCRIPT_WEIGHT: usize = 133; +/// The weight of a BIP141 witnessScript for a BOLT3's "offered HTLC output" on a commitment transaction, anchor variant. +pub const OFFERED_HTLC_SCRIPT_WEIGHT_ANCHORS: usize = 136; + +/// The weight of a BIP141 witnessScript for a BOLT3's "received HTLC output" can vary in function of its CLTV argument value. +/// We define a range that encompasses both its non-anchors and anchors variants. pub(crate) const MIN_ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 136; -pub(crate) const MAX_ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 143; +/// The weight of a BIP141 witnessScript for a BOLT3's "received HTLC output" can vary in function of its CLTV argument value. +/// We define a range that encompasses both its non-anchors and anchors variants. +/// This is the maximum post-anchor value. +pub const MAX_ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 143; /// Gets the weight for an HTLC-Success transaction. #[inline] @@ -65,18 +73,24 @@ pub fn htlc_timeout_tx_weight(opt_anchors: bool) -> u64 { if opt_anchors { HTLC_TIMEOUT_ANCHOR_TX_WEIGHT } else { HTLC_TIMEOUT_TX_WEIGHT } } +/// Describes the type of HTLC claim as determined by analyzing the witness. #[derive(PartialEq, Eq)] -pub(crate) enum HTLCClaim { +pub enum HTLCClaim { + /// Claims an offered output on a commitment transaction through the timeout path. OfferedTimeout, + /// Claims an offered output on a commitment transaction through the success path. OfferedPreimage, + /// Claims an accepted output on a commitment transaction through the timeout path. AcceptedTimeout, + /// Claims an accepted output on a commitment transaction through the success path. AcceptedPreimage, + /// Claims an offered/accepted output on a commitment transaction through the revocation path. Revocation, } impl HTLCClaim { /// Check if a given input witness attempts to claim a HTLC. - pub(crate) fn from_witness(witness: &Witness) -> Option { + pub fn from_witness(witness: &Witness) -> Option { debug_assert_eq!(OFFERED_HTLC_SCRIPT_WEIGHT_ANCHORS, MIN_ACCEPTED_HTLC_SCRIPT_WEIGHT); if witness.len() < 2 { return None; @@ -660,7 +674,7 @@ pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &Pub /// /// Panics if htlc.transaction_output_index.is_none() (as such HTLCs do not appear in the /// commitment transaction). -pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, opt_anchors: bool, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction { +pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, opt_anchors: bool, use_non_zero_fee_anchors: bool, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction { let mut txins: Vec = Vec::new(); txins.push(TxIn { previous_output: OutPoint { @@ -677,7 +691,7 @@ pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, conte } else { htlc_success_tx_weight(opt_anchors) }; - let output_value = if opt_anchors { + let output_value = if opt_anchors && !use_non_zero_fee_anchors { htlc.amount_msat / 1000 } else { let total_fee = feerate_per_kw as u64 * weight / 1000; @@ -700,7 +714,7 @@ pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, conte /// Gets the witnessScript for the to_remote output when anchors are enabled. #[inline] -pub(crate) fn get_to_countersignatory_with_anchors_redeemscript(payment_point: &PublicKey) -> Script { +pub fn get_to_countersignatory_with_anchors_redeemscript(payment_point: &PublicKey) -> Script { Builder::new() .push_slice(&payment_point.serialize()[..]) .push_opcode(opcodes::all::OP_CHECKSIGVERIFY) @@ -765,7 +779,11 @@ pub struct ChannelTransactionParameters { pub funding_outpoint: Option, /// Are anchors (zero fee HTLC transaction variant) used for this channel. Boolean is /// serialization backwards-compatible. - pub opt_anchors: Option<()> + pub opt_anchors: Option<()>, + /// Are non-zero-fee anchors are enabled (used in conjuction with opt_anchors) + /// It is intended merely for backwards compatibility with signers that need it. + /// There is no support for this feature in LDK channel negotiation. + pub opt_non_zero_fee_anchors: Option<()>, } /// Late-bound per-channel counterparty data used to build transactions. @@ -820,6 +838,7 @@ impl_writeable_tlv_based!(ChannelTransactionParameters, { (6, counterparty_parameters, option), (8, funding_outpoint, option), (10, opt_anchors, option), + (12, opt_non_zero_fee_anchors, option), }); /// Static channel fields used to build transactions given per-commitment fields, organized by @@ -942,7 +961,8 @@ impl HolderCommitmentTransaction { is_outbound_from_holder: false, counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: channel_pubkeys.clone(), selected_contest_delay: 0 }), funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }), - opt_anchors: None + opt_anchors: None, + opt_non_zero_fee_anchors: None, }; let mut htlcs_with_aux: Vec<(_, ())> = Vec::new(); let inner = CommitmentTransaction::new_with_auxiliary_htlc_data(0, 0, 0, false, dummy_key.clone(), dummy_key.clone(), keys, 0, &mut htlcs_with_aux, &channel_parameters.as_counterparty_broadcastable()); @@ -1160,6 +1180,8 @@ pub struct CommitmentTransaction { htlcs: Vec, // A boolean that is serialization backwards-compatible opt_anchors: Option<()>, + // Whether non-zero-fee anchors should be used + opt_non_zero_fee_anchors: Option<()>, // A cache of the parties' pubkeys required to construct the transaction, see doc for trust() keys: TxCreationKeys, // For access to the pre-built transaction, see doc for trust() @@ -1193,6 +1215,7 @@ impl_writeable_tlv_based!(CommitmentTransaction, { (10, built, required), (12, htlcs, vec_type), (14, opt_anchors, option), + (16, opt_non_zero_fee_anchors, option), }); impl CommitmentTransaction { @@ -1225,9 +1248,18 @@ impl CommitmentTransaction { transaction, txid }, + opt_non_zero_fee_anchors: None, } } + /// Use non-zero fee anchors + /// + /// (C-not exported) due to move, and also not likely to be useful for binding users + pub fn with_non_zero_fee_anchors(mut self) -> Self { + self.opt_non_zero_fee_anchors = Some(()); + self + } + fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_funding_key: &PublicKey, countersignatory_funding_key: &PublicKey) -> Result { let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters); @@ -1266,7 +1298,7 @@ impl CommitmentTransaction { let script = if opt_anchors { get_to_countersignatory_with_anchors_redeemscript(&countersignatory_pubkeys.payment_point).to_v0_p2wsh() } else { - get_p2wpkh_redeemscript(&countersignatory_pubkeys.payment_point) + Payload::p2wpkh(&BitcoinPublicKey::new(countersignatory_pubkeys.payment_point)).unwrap().script_pubkey() }; txouts.push(( TxOut { @@ -1492,7 +1524,7 @@ impl<'a> TrustedCommitmentTransaction<'a> { for this_htlc in inner.htlcs.iter() { assert!(this_htlc.transaction_output_index.is_some()); - let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, self.opt_anchors(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); + let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, self.opt_anchors(), self.opt_non_zero_fee_anchors.is_some(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, self.opt_anchors(), &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key); @@ -1514,7 +1546,7 @@ impl<'a> TrustedCommitmentTransaction<'a> { // Further, we should never be provided the preimage for an HTLC-Timeout transaction. if this_htlc.offered && preimage.is_some() { unreachable!(); } - let mut htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, self.opt_anchors(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); + let mut htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, self.opt_anchors(), self.opt_non_zero_fee_anchors.is_some(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, self.opt_anchors(), &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key); @@ -1572,18 +1604,12 @@ pub fn get_commitment_transaction_number_obscure_factor( | ((res[31] as u64) << 0 * 8) } -fn get_p2wpkh_redeemscript(key: &PublicKey) -> Script { - Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0) - .push_slice(&WPubkeyHash::hash(&key.serialize())[..]) - .into_script() -} - #[cfg(test)] mod tests { use super::CounterpartyCommitmentSecrets; use crate::{hex, chain}; use crate::prelude::*; - use crate::ln::chan_utils::{get_htlc_redeemscript, get_to_countersignatory_with_anchors_redeemscript, get_p2wpkh_redeemscript, CommitmentTransaction, TxCreationKeys, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, HTLCOutputInCommitment}; + use crate::ln::chan_utils::{get_htlc_redeemscript, get_to_countersignatory_with_anchors_redeemscript, CommitmentTransaction, TxCreationKeys, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, HTLCOutputInCommitment}; use bitcoin::secp256k1::{PublicKey, SecretKey, Secp256k1}; use crate::util::test_utils; use crate::chain::keysinterface::{KeysInterface, BaseSign}; @@ -1591,6 +1617,8 @@ mod tests { use bitcoin::hashes::Hash; use crate::ln::PaymentHash; use bitcoin::hashes::hex::ToHex; + use bitcoin::util::address::Payload; + use bitcoin::PublicKey as BitcoinPublicKey; #[test] fn test_anchors() { @@ -1614,7 +1642,8 @@ mod tests { is_outbound_from_holder: false, counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: counterparty_pubkeys.clone(), selected_contest_delay: 0 }), funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }), - opt_anchors: None + opt_anchors: None, + opt_non_zero_fee_anchors: None, }; let mut htlcs_with_aux: Vec<(_, ())> = Vec::new(); @@ -1629,7 +1658,7 @@ mod tests { &mut htlcs_with_aux, &channel_parameters.as_holder_broadcastable() ); assert_eq!(tx.built.transaction.output.len(), 2); - assert_eq!(tx.built.transaction.output[1].script_pubkey, get_p2wpkh_redeemscript(&counterparty_pubkeys.payment_point)); + assert_eq!(tx.built.transaction.output[1].script_pubkey, Payload::p2wpkh(&BitcoinPublicKey::new(counterparty_pubkeys.payment_point)).unwrap().script_pubkey()); // Generate broadcaster and counterparty outputs as well as two anchors let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(