X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchan_utils.rs;h=c229819c3b64e6d3e875002c814190a1d40e153e;hb=07db23d102738d1e84e3d2cb36101cef92e1761d;hp=3fd489fa1a94348b1c9bc9d0faac1a6dd1ddff88;hpb=ce4de5fb52246f91d37127594f8fd7d304ab86ad;p=rust-lightning diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs index 3fd489fa..c229819c 100644 --- a/lightning/src/ln/chan_utils.rs +++ b/lightning/src/ln/chan_utils.rs @@ -8,20 +8,23 @@ use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, SigHashTy use bitcoin::consensus::encode::{self, Decodable, Encodable}; use bitcoin::util::bip143; -use bitcoin_hashes::{Hash, HashEngine}; -use bitcoin_hashes::sha256::Hash as Sha256; -use bitcoin_hashes::ripemd160::Hash as Ripemd160; -use bitcoin_hashes::hash160::Hash as Hash160; -use bitcoin_hashes::sha256d::Hash as Sha256dHash; +use bitcoin::hashes::{Hash, HashEngine}; +use bitcoin::hashes::sha256::Hash as Sha256; +use bitcoin::hashes::ripemd160::Hash as Ripemd160; +use bitcoin::hash_types::{Txid, PubkeyHash}; use ln::channelmanager::{PaymentHash, PaymentPreimage}; use ln::msgs::DecodeError; use util::ser::{Readable, Writeable, Writer, WriterWriteAdaptor}; use util::byte_utils; -use secp256k1::key::{SecretKey, PublicKey}; -use secp256k1::{Secp256k1, Signature}; -use secp256k1; +use bitcoin::secp256k1::key::{SecretKey, PublicKey}; +use bitcoin::secp256k1::{Secp256k1, Signature}; +use bitcoin::secp256k1; + +use std::{cmp, mem}; + +const MAX_ALLOC_SIZE: usize = 64*1024; pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703; pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663; @@ -156,8 +159,8 @@ impl Writeable for CounterpartyCommitmentSecrets { Ok(()) } } -impl Readable for CounterpartyCommitmentSecrets { - fn read(reader: &mut R) -> Result { +impl Readable for CounterpartyCommitmentSecrets { + fn read(reader: &mut R) -> Result { let mut old_secrets = [([0; 32], 1 << 48); 49]; for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() { *secret = Readable::read(reader)?; @@ -259,11 +262,9 @@ pub struct TxCreationKeys { pub(crate) b_htlc_key: PublicKey, /// A's Payment Key (which isn't allowed to be spent from for some delay) pub(crate) a_delayed_payment_key: PublicKey, - /// B's Payment Key - pub(crate) b_payment_key: PublicKey, } impl_writeable!(TxCreationKeys, 33*6, - { per_commitment_point, revocation_key, a_htlc_key, b_htlc_key, a_delayed_payment_key, b_payment_key }); + { per_commitment_point, revocation_key, a_htlc_key, b_htlc_key, a_delayed_payment_key }); /// One counterparty's public keys which do not change over the life of a channel. #[derive(Clone, PartialEq)] @@ -276,9 +277,10 @@ pub struct ChannelPublicKeys { /// a commitment transaction so that their counterparty can claim all available funds if they /// broadcast an old state. pub revocation_basepoint: PublicKey, - /// The base point which is used (with derive_public_key) to derive a per-commitment payment - /// public key which receives immediately-spendable non-HTLC-encumbered funds. - pub payment_basepoint: PublicKey, + /// The public key which receives our immediately spendable primary channel balance in + /// remote-broadcasted commitment transactions. This key is static across every commitment + /// transaction. + pub payment_point: PublicKey, /// The base point which is used (with derive_public_key) to derive a per-commitment payment /// public key which receives non-HTLC-encumbered funds which are only available for spending /// after some delay (or can be claimed via the revocation path). @@ -291,21 +293,20 @@ pub struct ChannelPublicKeys { impl_writeable!(ChannelPublicKeys, 33*5, { funding_pubkey, revocation_basepoint, - payment_basepoint, + payment_point, delayed_payment_basepoint, htlc_basepoint }); impl TxCreationKeys { - pub(crate) fn new(secp_ctx: &Secp256k1, per_commitment_point: &PublicKey, a_delayed_payment_base: &PublicKey, a_htlc_base: &PublicKey, b_revocation_base: &PublicKey, b_payment_base: &PublicKey, b_htlc_base: &PublicKey) -> Result { + pub(crate) fn new(secp_ctx: &Secp256k1, per_commitment_point: &PublicKey, a_delayed_payment_base: &PublicKey, a_htlc_base: &PublicKey, b_revocation_base: &PublicKey, b_htlc_base: &PublicKey) -> Result { Ok(TxCreationKeys { per_commitment_point: per_commitment_point.clone(), revocation_key: derive_public_revocation_key(&secp_ctx, &per_commitment_point, &b_revocation_base)?, a_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &a_htlc_base)?, b_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &b_htlc_base)?, a_delayed_payment_key: derive_public_key(&secp_ctx, &per_commitment_point, &a_delayed_payment_base)?, - b_payment_key: derive_public_key(&secp_ctx, &per_commitment_point, &b_payment_base)?, }) } } @@ -355,12 +356,12 @@ impl_writeable!(HTLCOutputInCommitment, 1 + 8 + 4 + 32 + 5, { }); #[inline] -pub(super) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, a_htlc_key: &PublicKey, b_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script { +pub(crate) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, a_htlc_key: &PublicKey, b_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script { let payment_hash160 = Ripemd160::hash(&htlc.payment_hash.0[..]).into_inner(); if htlc.offered { Builder::new().push_opcode(opcodes::all::OP_DUP) .push_opcode(opcodes::all::OP_HASH160) - .push_slice(&Hash160::hash(&revocation_key.serialize())[..]) + .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..]) .push_opcode(opcodes::all::OP_EQUAL) .push_opcode(opcodes::all::OP_IF) .push_opcode(opcodes::all::OP_CHECKSIG) @@ -388,7 +389,7 @@ pub(super) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommit } else { Builder::new().push_opcode(opcodes::all::OP_DUP) .push_opcode(opcodes::all::OP_HASH160) - .push_slice(&Hash160::hash(&revocation_key.serialize())[..]) + .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..]) .push_opcode(opcodes::all::OP_EQUAL) .push_opcode(opcodes::all::OP_IF) .push_opcode(opcodes::all::OP_CHECKSIG) @@ -443,7 +444,7 @@ pub fn make_funding_redeemscript(a: &PublicKey, b: &PublicKey) -> Script { } /// panics if htlc.transaction_output_index.is_none()! -pub fn build_htlc_transaction(prev_hash: &Sha256dHash, feerate_per_kw: u64, to_self_delay: u16, htlc: &HTLCOutputInCommitment, a_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction { +pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u64, to_self_delay: u16, htlc: &HTLCOutputInCommitment, a_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction { let mut txins: Vec = Vec::new(); txins.push(TxIn { previous_output: OutPoint { @@ -475,119 +476,186 @@ pub fn build_htlc_transaction(prev_hash: &Sha256dHash, feerate_per_kw: u64, to_s } } -/// Signs a transaction created by build_htlc_transaction. If the transaction is an -/// HTLC-Success transaction (ie htlc.offered is false), preimage must be set! -pub(crate) fn sign_htlc_transaction(tx: &mut Transaction, their_sig: &Signature, preimage: &Option, htlc: &HTLCOutputInCommitment, a_htlc_key: &PublicKey, b_htlc_key: &PublicKey, revocation_key: &PublicKey, per_commitment_point: &PublicKey, htlc_base_key: &SecretKey, secp_ctx: &Secp256k1) -> Result<(Signature, Script), ()> { - if tx.input.len() != 1 { return Err(()); } - if tx.input[0].witness.len() != 0 { return Err(()); } - - let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&htlc, a_htlc_key, b_htlc_key, revocation_key); - - let our_htlc_key = derive_private_key(secp_ctx, per_commitment_point, htlc_base_key).map_err(|_| ())?; - let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]); - let local_tx = PublicKey::from_secret_key(&secp_ctx, &our_htlc_key) == *a_htlc_key; - let our_sig = secp_ctx.sign(&sighash, &our_htlc_key); - - tx.input[0].witness.push(Vec::new()); // First is the multisig dummy - - if local_tx { // b, then a - tx.input[0].witness.push(their_sig.serialize_der().to_vec()); - tx.input[0].witness.push(our_sig.serialize_der().to_vec()); - } else { - tx.input[0].witness.push(our_sig.serialize_der().to_vec()); - tx.input[0].witness.push(their_sig.serialize_der().to_vec()); - } - tx.input[0].witness[1].push(SigHashType::All as u8); - tx.input[0].witness[2].push(SigHashType::All as u8); - - if htlc.offered { - tx.input[0].witness.push(Vec::new()); - assert!(preimage.is_none()); - } else { - tx.input[0].witness.push(preimage.unwrap().0.to_vec()); - } - - tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec()); - - Ok((our_sig, htlc_redeemscript)) -} - #[derive(Clone)] /// We use this to track local commitment transactions and put off signing them until we are ready /// to broadcast. Eventually this will require a signer which is possibly external, but for now we /// just pass in the SecretKeys required. -pub(crate) struct LocalCommitmentTransaction { - tx: Transaction +pub struct LocalCommitmentTransaction { + // TODO: We should migrate away from providing the transaction, instead providing enough to + // allow the ChannelKeys to construct it from scratch. Luckily we already have HTLC data here, + // so we're probably most of the way there. + /// The commitment transaction itself, in unsigned form. + pub unsigned_tx: Transaction, + /// Our counterparty's signature for the transaction, above. + pub their_sig: Signature, + // Which order the signatures should go in when constructing the final commitment tx witness. + // The user should be able to reconstruc this themselves, so we don't bother to expose it. + our_sig_first: bool, + /// The key derivation parameters for this commitment transaction + pub local_keys: TxCreationKeys, + /// The feerate paid per 1000-weight-unit in this commitment transaction. This value is + /// controlled by the channel initiator. + pub feerate_per_kw: u64, + /// The HTLCs and remote htlc signatures which were included in this commitment transaction. + /// + /// Note that this includes all HTLCs, including ones which were considered dust and not + /// actually included in the transaction as it appears on-chain, but who's value is burned as + /// fees and not included in the to_local or to_remote outputs. + /// + /// The remote HTLC signatures in the second element will always be set for non-dust HTLCs, ie + /// those for which transaction_output_index.is_some(). + pub per_htlc: Vec<(HTLCOutputInCommitment, Option)>, } impl LocalCommitmentTransaction { #[cfg(test)] pub fn dummy() -> Self { - Self { tx: Transaction { - version: 2, - input: Vec::new(), - output: Vec::new(), - lock_time: 0, - } } + let dummy_input = TxIn { + previous_output: OutPoint { + txid: Default::default(), + vout: 0, + }, + script_sig: Default::default(), + sequence: 0, + witness: vec![] + }; + let dummy_key = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&[42; 32]).unwrap()); + let dummy_sig = Secp256k1::new().sign(&secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap()); + Self { + unsigned_tx: Transaction { + version: 2, + input: vec![dummy_input], + output: Vec::new(), + lock_time: 0, + }, + their_sig: dummy_sig, + our_sig_first: false, + local_keys: TxCreationKeys { + per_commitment_point: dummy_key.clone(), + revocation_key: dummy_key.clone(), + a_htlc_key: dummy_key.clone(), + b_htlc_key: dummy_key.clone(), + a_delayed_payment_key: dummy_key.clone(), + }, + feerate_per_kw: 0, + per_htlc: Vec::new() + } } - pub fn new_missing_local_sig(mut tx: Transaction, their_sig: &Signature, our_funding_key: &PublicKey, their_funding_key: &PublicKey) -> LocalCommitmentTransaction { - if tx.input.len() != 1 { panic!("Tried to store a commitment transaction that had input count != 1!"); } - if tx.input[0].witness.len() != 0 { panic!("Tried to store a signed commitment transaction?"); } - - tx.input[0].witness.push(Vec::new()); // First is the multisig dummy - - if our_funding_key.serialize()[..] < their_funding_key.serialize()[..] { - tx.input[0].witness.push(Vec::new()); - tx.input[0].witness.push(their_sig.serialize_der().to_vec()); - tx.input[0].witness[2].push(SigHashType::All as u8); - } else { - tx.input[0].witness.push(their_sig.serialize_der().to_vec()); - tx.input[0].witness[1].push(SigHashType::All as u8); - tx.input[0].witness.push(Vec::new()); + /// Generate a new LocalCommitmentTransaction based on a raw commitment transaction, + /// remote signature and both parties keys + pub(crate) fn new_missing_local_sig(unsigned_tx: Transaction, their_sig: Signature, our_funding_key: &PublicKey, their_funding_key: &PublicKey, local_keys: TxCreationKeys, feerate_per_kw: u64, htlc_data: Vec<(HTLCOutputInCommitment, Option)>) -> LocalCommitmentTransaction { + if unsigned_tx.input.len() != 1 { panic!("Tried to store a commitment transaction that had input count != 1!"); } + if unsigned_tx.input[0].witness.len() != 0 { panic!("Tried to store a signed commitment transaction?"); } + + Self { + unsigned_tx, + their_sig, + our_sig_first: our_funding_key.serialize()[..] < their_funding_key.serialize()[..], + local_keys, + feerate_per_kw, + per_htlc: htlc_data, } + } - Self { tx } + /// Get the txid of the local commitment transaction contained in this + /// LocalCommitmentTransaction + pub fn txid(&self) -> Txid { + self.unsigned_tx.txid() } - pub fn txid(&self) -> Sha256dHash { - self.tx.txid() + /// Gets our signature for the contained commitment transaction given our funding private key. + /// + /// Funding key is your key included in the 2-2 funding_outpoint lock. Should be provided + /// by your ChannelKeys. + /// Funding redeemscript is script locking funding_outpoint. This is the mutlsig script + /// between your own funding key and your counterparty's. Currently, this is provided in + /// ChannelKeys::sign_local_commitment() calls directly. + /// Channel value is amount locked in funding_outpoint. + pub fn get_local_sig(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1) -> Signature { + let sighash = hash_to_message!(&bip143::SighashComponents::new(&self.unsigned_tx) + .sighash_all(&self.unsigned_tx.input[0], funding_redeemscript, channel_value_satoshis)[..]); + secp_ctx.sign(&sighash, funding_key) } - pub fn has_local_sig(&self) -> bool { - if self.tx.input.len() != 1 { panic!("Commitment transactions must have input count == 1!"); } - if self.tx.input[0].witness.len() == 4 { - assert!(!self.tx.input[0].witness[1].is_empty()); - assert!(!self.tx.input[0].witness[2].is_empty()); - true + pub(crate) fn add_local_sig(&self, funding_redeemscript: &Script, our_sig: Signature) -> Transaction { + let mut tx = self.unsigned_tx.clone(); + // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element. + tx.input[0].witness.push(Vec::new()); + + if self.our_sig_first { + tx.input[0].witness.push(our_sig.serialize_der().to_vec()); + tx.input[0].witness.push(self.their_sig.serialize_der().to_vec()); } else { - assert_eq!(self.tx.input[0].witness.len(), 3); - assert!(self.tx.input[0].witness[0].is_empty()); - assert!(self.tx.input[0].witness[1].is_empty() || self.tx.input[0].witness[2].is_empty()); - false + tx.input[0].witness.push(self.their_sig.serialize_der().to_vec()); + tx.input[0].witness.push(our_sig.serialize_der().to_vec()); } + tx.input[0].witness[1].push(SigHashType::All as u8); + tx.input[0].witness[2].push(SigHashType::All as u8); + + tx.input[0].witness.push(funding_redeemscript.as_bytes().to_vec()); + tx } - pub fn add_local_sig(&mut self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1) { - if self.has_local_sig() { return; } - let sighash = hash_to_message!(&bip143::SighashComponents::new(&self.tx) - .sighash_all(&self.tx.input[0], funding_redeemscript, channel_value_satoshis)[..]); - let our_sig = secp_ctx.sign(&sighash, funding_key); + /// Get a signature for each HTLC which was included in the commitment transaction (ie for + /// which HTLCOutputInCommitment::transaction_output_index.is_some()). + /// + /// The returned Vec has one entry for each HTLC, and in the same order. For HTLCs which were + /// considered dust and not included, a None entry exists, for all others a signature is + /// included. + pub fn get_htlc_sigs(&self, htlc_base_key: &SecretKey, local_csv: u16, secp_ctx: &Secp256k1) -> Result>, ()> { + let txid = self.txid(); + let mut ret = Vec::with_capacity(self.per_htlc.len()); + let our_htlc_key = derive_private_key(secp_ctx, &self.local_keys.per_commitment_point, htlc_base_key).map_err(|_| ())?; + + for this_htlc in self.per_htlc.iter() { + if this_htlc.0.transaction_output_index.is_some() { + let htlc_tx = build_htlc_transaction(&txid, self.feerate_per_kw, local_csv, &this_htlc.0, &self.local_keys.a_delayed_payment_key, &self.local_keys.revocation_key); + + let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc.0, &self.local_keys.a_htlc_key, &self.local_keys.b_htlc_key, &self.local_keys.revocation_key); + + let sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, this_htlc.0.amount_msat / 1000)[..]); + ret.push(Some(secp_ctx.sign(&sighash, &our_htlc_key))); + } else { + ret.push(None); + } + } + Ok(ret) + } - if self.tx.input[0].witness[1].is_empty() { - self.tx.input[0].witness[1] = our_sig.serialize_der().to_vec(); - self.tx.input[0].witness[1].push(SigHashType::All as u8); + /// Gets a signed HTLC transaction given a preimage (for !htlc.offered) and the local HTLC transaction signature. + pub(crate) fn get_signed_htlc_tx(&self, htlc_index: usize, signature: &Signature, preimage: &Option, local_csv: u16) -> Transaction { + let txid = self.txid(); + let this_htlc = &self.per_htlc[htlc_index]; + assert!(this_htlc.0.transaction_output_index.is_some()); + // if we don't have preimage for an HTLC-Success, we can't generate an HTLC transaction. + if !this_htlc.0.offered && preimage.is_none() { unreachable!(); } + // Further, we should never be provided the preimage for an HTLC-Timeout transaction. + if this_htlc.0.offered && preimage.is_some() { unreachable!(); } + + let mut htlc_tx = build_htlc_transaction(&txid, self.feerate_per_kw, local_csv, &this_htlc.0, &self.local_keys.a_delayed_payment_key, &self.local_keys.revocation_key); + // Channel should have checked that we have a remote signature for this HTLC at + // creation, and we should have a sensible htlc transaction: + assert!(this_htlc.1.is_some()); + + let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc.0, &self.local_keys.a_htlc_key, &self.local_keys.b_htlc_key, &self.local_keys.revocation_key); + + // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element. + htlc_tx.input[0].witness.push(Vec::new()); + + htlc_tx.input[0].witness.push(this_htlc.1.unwrap().serialize_der().to_vec()); + htlc_tx.input[0].witness.push(signature.serialize_der().to_vec()); + htlc_tx.input[0].witness[1].push(SigHashType::All as u8); + htlc_tx.input[0].witness[2].push(SigHashType::All as u8); + + if this_htlc.0.offered { + // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay. + htlc_tx.input[0].witness.push(Vec::new()); } else { - self.tx.input[0].witness[2] = our_sig.serialize_der().to_vec(); - self.tx.input[0].witness[2].push(SigHashType::All as u8); + htlc_tx.input[0].witness.push(preimage.unwrap().0.to_vec()); } - self.tx.input[0].witness.push(funding_redeemscript.as_bytes().to_vec()); - } - - pub fn without_valid_witness(&self) -> &Transaction { &self.tx } - pub fn with_valid_witness(&self) -> &Transaction { - assert!(self.has_local_sig()); - &self.tx + htlc_tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec()); + htlc_tx } } impl PartialEq for LocalCommitmentTransaction { @@ -598,30 +666,57 @@ impl PartialEq for LocalCommitmentTransaction { } impl Writeable for LocalCommitmentTransaction { fn write(&self, writer: &mut W) -> Result<(), ::std::io::Error> { - if let Err(e) = self.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) { + if let Err(e) = self.unsigned_tx.consensus_encode(&mut WriterWriteAdaptor(writer)) { match e { encode::Error::Io(e) => return Err(e), _ => panic!("local tx must have been well-formed!"), } } + self.their_sig.write(writer)?; + self.our_sig_first.write(writer)?; + self.local_keys.write(writer)?; + self.feerate_per_kw.write(writer)?; + writer.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?; + for &(ref htlc, ref sig) in self.per_htlc.iter() { + htlc.write(writer)?; + sig.write(writer)?; + } Ok(()) } } -impl Readable for LocalCommitmentTransaction { - fn read(reader: &mut R) -> Result { - let tx = match Transaction::consensus_decode(reader.by_ref()) { +impl Readable for LocalCommitmentTransaction { + fn read(reader: &mut R) -> Result { + let unsigned_tx = match Transaction::consensus_decode(reader.by_ref()) { Ok(tx) => tx, Err(e) => match e { encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)), _ => return Err(DecodeError::InvalidValue), }, }; + let their_sig = Readable::read(reader)?; + let our_sig_first = Readable::read(reader)?; + let local_keys = Readable::read(reader)?; + let feerate_per_kw = Readable::read(reader)?; + let htlcs_count: u64 = Readable::read(reader)?; + let mut per_htlc = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / mem::size_of::<(HTLCOutputInCommitment, Option)>())); + for _ in 0..htlcs_count { + let htlc: HTLCOutputInCommitment = Readable::read(reader)?; + let sigs = Readable::read(reader)?; + per_htlc.push((htlc, sigs)); + } - if tx.input.len() != 1 { + if unsigned_tx.input.len() != 1 { // Ensure tx didn't hit the 0-input ambiguity case. return Err(DecodeError::InvalidValue); } - Ok(Self { tx }) + Ok(Self { + unsigned_tx, + their_sig, + our_sig_first, + local_keys, + feerate_per_kw, + per_htlc, + }) } }