From: Matt Corallo <649246+TheBlueMatt@users.noreply.github.com> Date: Sat, 28 Dec 2019 17:50:09 +0000 (+0000) Subject: Merge pull request #420 from TheBlueMatt/2019-12-chan-ext-signer X-Git-Tag: v0.0.12~163 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=9310813e9807ce390ceff25c42351c76ddaf9431;hp=f755ae5bbaf46a1fec43f374146293067b3494f5;p=rust-lightning Merge pull request #420 from TheBlueMatt/2019-12-chan-ext-signer Remove signing from Channel --- diff --git a/fuzz/src/chanmon_consistency.rs b/fuzz/src/chanmon_consistency.rs index 3cae8f8e..52d5a658 100644 --- a/fuzz/src/chanmon_consistency.rs +++ b/fuzz/src/chanmon_consistency.rs @@ -212,7 +212,7 @@ pub fn do_test(data: &[u8]) { monitor.latest_good_update.lock().unwrap().insert(outpoint, monitor_ser); } let mut monitor_refs = HashMap::new(); - for (outpoint, monitor) in monitors.iter() { + for (outpoint, monitor) in monitors.iter_mut() { monitor_refs.insert(*outpoint, monitor); } @@ -223,7 +223,7 @@ pub fn do_test(data: &[u8]) { tx_broadcaster: broadcast.clone(), logger, default_config: config, - channel_monitors: &monitor_refs, + channel_monitors: &mut monitor_refs, }; let res = (<(Sha256d, ChannelManager)>::read(&mut Cursor::new(&$ser.0), read_args).expect("Failed to read manager").1, monitor); diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index 2a8910b0..fae609cc 100644 --- a/lightning/src/chain/keysinterface.rs +++ b/lightning/src/chain/keysinterface.rs @@ -142,7 +142,7 @@ pub trait ChannelKeys : Send { /// TODO: Document the things someone using this interface should enforce before signing. /// TODO: Add more input vars to enable better checking (preferably removing commitment_tx and /// making the callee generate it via some util function we expose)! - fn sign_remote_commitment(&self, channel_value_satoshis: u64, channel_funding_redeemscript: &Script, absolute_fee: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + fn sign_remote_commitment(&self, channel_value_satoshis: u64, channel_funding_redeemscript: &Script, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; /// Create a signature for a (proposed) closing transaction. /// diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs index 19b3440e..747e622f 100644 --- a/lightning/src/ln/chan_utils.rs +++ b/lightning/src/ln/chan_utils.rs @@ -4,7 +4,9 @@ use bitcoin::blockdata::script::{Script,Builder}; use bitcoin::blockdata::opcodes; -use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction}; +use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, SigHashType}; +use bitcoin::consensus::encode::{self, Decodable, Encodable}; +use bitcoin::util::bip143; use bitcoin_hashes::{Hash, HashEngine}; use bitcoin_hashes::sha256::Hash as Sha256; @@ -12,10 +14,12 @@ use bitcoin_hashes::ripemd160::Hash as Ripemd160; use bitcoin_hashes::hash160::Hash as Hash160; use bitcoin_hashes::sha256d::Hash as Sha256dHash; -use ln::channelmanager::PaymentHash; +use ln::channelmanager::{PaymentHash, PaymentPreimage}; +use ln::msgs::DecodeError; +use util::ser::{Readable, Writeable, Writer, WriterWriteAdaptor}; -use secp256k1::key::{PublicKey,SecretKey}; -use secp256k1::Secp256k1; +use secp256k1::key::{SecretKey,PublicKey}; +use secp256k1::{Secp256k1, Signature}; use secp256k1; pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703; @@ -59,7 +63,9 @@ pub(super) fn derive_public_key(secp_ctx: &Secp256k1, base_point.combine(&hashkey) } -/// Derives a revocation key from its constituent parts +/// Derives a revocation key from its constituent parts. +/// Note that this is infallible iff we trust that at least one of the two input keys are randomly +/// generated (ie our own). pub(super) fn derive_private_revocation_key(secp_ctx: &Secp256k1, per_commitment_secret: &SecretKey, revocation_base_secret: &SecretKey) -> Result { let revocation_base_point = PublicKey::from_secret_key(&secp_ctx, &revocation_base_secret); let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret); @@ -281,3 +287,153 @@ pub fn build_htlc_transaction(prev_hash: &Sha256dHash, feerate_per_kw: u64, to_s output: txouts, } } + +/// 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 +} +impl LocalCommitmentTransaction { + #[cfg(test)] + pub fn dummy() -> Self { + Self { tx: Transaction { + version: 2, + input: Vec::new(), + output: Vec::new(), + lock_time: 0, + } } + } + + 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()); + } + + Self { tx } + } + + pub fn txid(&self) -> Sha256dHash { + self.tx.txid() + } + + 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 + } 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 + } + } + + 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); + + 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); + } else { + self.tx.input[0].witness[2] = our_sig.serialize_der().to_vec(); + self.tx.input[0].witness[2].push(SigHashType::All as u8); + } + + 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 + } +} +impl PartialEq for LocalCommitmentTransaction { + // We dont care whether we are signed in equality comparison + fn eq(&self, o: &Self) -> bool { + self.txid() == o.txid() + } +} +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)) { + match e { + encode::Error::Io(e) => return Err(e), + _ => panic!("local tx must have been well-formed!"), + } + } + Ok(()) + } +} +impl Readable for LocalCommitmentTransaction { + fn read(reader: &mut R) -> Result { + let 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), + }, + }; + + if tx.input.len() != 1 { + // Ensure tx didn't hit the 0-input ambiguity case. + return Err(DecodeError::InvalidValue); + } + Ok(Self { tx }) + } +} diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index f1330fb9..bba65e52 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -4,7 +4,7 @@ use bitcoin::blockdata::transaction::{TxIn, TxOut, Transaction, SigHashType}; use bitcoin::blockdata::opcodes; use bitcoin::util::hash::BitcoinHash; use bitcoin::util::bip143; -use bitcoin::consensus::encode::{self, Encodable, Decodable}; +use bitcoin::consensus::encode; use bitcoin_hashes::{Hash, HashEngine}; use bitcoin_hashes::sha256::Hash as Sha256; @@ -19,13 +19,13 @@ use ln::msgs; use ln::msgs::{DecodeError, OptionalField, LocalFeatures, DataLossProtect}; use ln::channelmonitor::ChannelMonitor; use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingForwardHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT}; -use ln::chan_utils::{TxCreationKeys,HTLCOutputInCommitment,HTLC_SUCCESS_TX_WEIGHT,HTLC_TIMEOUT_TX_WEIGHT}; +use ln::chan_utils::{LocalCommitmentTransaction,TxCreationKeys,HTLCOutputInCommitment,HTLC_SUCCESS_TX_WEIGHT,HTLC_TIMEOUT_TX_WEIGHT}; use ln::chan_utils; use chain::chaininterface::{FeeEstimator,ConfirmationTarget}; use chain::transaction::OutPoint; use chain::keysinterface::{ChannelKeys, KeysInterface}; use util::transaction_utils; -use util::ser::{Readable, ReadableArgs, Writeable, Writer, WriterWriteAdaptor}; +use util::ser::{Readable, ReadableArgs, Writeable, Writer}; use util::logger::{Logger, LogHolder}; use util::errors::APIError; use util::config::{UserConfig,ChannelConfig}; @@ -297,12 +297,6 @@ pub(super) struct Channel { /// Max to_local and to_remote outputs in a remote-generated commitment transaction max_commitment_tx_output_remote: ::std::sync::Mutex<(u64, u64)>, - #[cfg(test)] - // Used in ChannelManager's tests to send a revoked transaction - pub last_local_commitment_txn: Vec, - #[cfg(not(test))] - last_local_commitment_txn: Vec, - last_sent_closing_fee: Option<(u64, u64, Signature)>, // (feerate, fee, our_sig) /// The hash of the block in which the funding transaction reached our CONF_TARGET. We use this @@ -456,7 +450,7 @@ impl Channel { let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal); let secp_ctx = Secp256k1::new(); - let channel_monitor = ChannelMonitor::new(chan_keys.revocation_base_key(), chan_keys.delayed_payment_base_key(), + let channel_monitor = ChannelMonitor::new(chan_keys.funding_key(), chan_keys.revocation_base_key(), chan_keys.delayed_payment_base_key(), chan_keys.htlc_base_key(), chan_keys.payment_base_key(), &keys_provider.get_shutdown_pubkey(), config.own_channel_config.our_to_self_delay, keys_provider.get_destination_script(), logger.clone()); @@ -498,8 +492,6 @@ impl Channel { #[cfg(debug_assertions)] max_commitment_tx_output_remote: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)), - last_local_commitment_txn: Vec::new(), - last_sent_closing_fee: None, funding_tx_confirmed_in: None, @@ -652,11 +644,9 @@ impl Channel { } let secp_ctx = Secp256k1::new(); - let mut channel_monitor = ChannelMonitor::new(chan_keys.revocation_base_key(), chan_keys.delayed_payment_base_key(), - chan_keys.htlc_base_key(), chan_keys.payment_base_key(), &keys_provider.get_shutdown_pubkey(), config.own_channel_config.our_to_self_delay, - keys_provider.get_destination_script(), logger.clone()); - channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint); - channel_monitor.set_their_to_self_delay(msg.to_self_delay); + let channel_monitor = ChannelMonitor::new(chan_keys.funding_key(), chan_keys.revocation_base_key(), chan_keys.delayed_payment_base_key(), + chan_keys.htlc_base_key(), chan_keys.payment_base_key(), &keys_provider.get_shutdown_pubkey(), config.own_channel_config.our_to_self_delay, + keys_provider.get_destination_script(), logger.clone()); let their_shutdown_scriptpubkey = if their_local_features.supports_upfront_shutdown_script() { match &msg.shutdown_scriptpubkey { @@ -716,8 +706,6 @@ impl Channel { #[cfg(debug_assertions)] max_commitment_tx_output_remote: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)), - last_local_commitment_txn: Vec::new(), - last_sent_closing_fee: None, funding_tx_confirmed_in: None, @@ -758,7 +746,8 @@ impl Channel { }; let obscure_factor = chan.get_commitment_transaction_number_obscure_factor(); - chan.channel_monitor.set_commitment_obscure_factor(obscure_factor); + let funding_redeemscript = chan.get_funding_redeemscript(); + chan.channel_monitor.set_basic_channel_info(&msg.htlc_basepoint, &msg.delayed_payment_basepoint, msg.to_self_delay, funding_redeemscript, msg.funding_satoshis, obscure_factor); Ok(chan) } @@ -1133,38 +1122,6 @@ impl Channel { }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script() } - fn sign_commitment_transaction(&self, tx: &mut Transaction, their_sig: &Signature) -> Signature { - if tx.input.len() != 1 { - panic!("Tried to sign commitment transaction that had input count != 1!"); - } - if tx.input[0].witness.len() != 0 { - panic!("Tried to re-sign commitment transaction"); - } - - let funding_redeemscript = self.get_funding_redeemscript(); - - let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]); - let our_sig = self.secp_ctx.sign(&sighash, self.local_keys.funding_key()); - - tx.input[0].witness.push(Vec::new()); // First is the multisig dummy - - let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()).serialize(); - let their_funding_key = self.their_funding_pubkey.unwrap().serialize(); - if our_funding_key[..] < their_funding_key[..] { - tx.input[0].witness.push(our_sig.serialize_der().to_vec()); - tx.input[0].witness.push(their_sig.serialize_der().to_vec()); - } else { - tx.input[0].witness.push(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.into_bytes()); - - our_sig - } - /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output /// @local is used only to convert relevant internal structures which refer to remote vs local /// to decide value of outputs and direction of HTLCs. @@ -1172,54 +1129,6 @@ impl Channel { chan_utils::build_htlc_transaction(prev_hash, feerate_per_kw, if local { self.their_to_self_delay } else { self.our_to_self_delay }, htlc, &keys.a_delayed_payment_key, &keys.revocation_key) } - fn create_htlc_tx_signature(&self, tx: &Transaction, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result<(Script, Signature, bool), ChannelError> { - if tx.input.len() != 1 { - panic!("Tried to sign HTLC transaction that had input count != 1!"); - } - - let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys); - - let our_htlc_key = secp_check!(chan_utils::derive_private_key(&self.secp_ctx, &keys.per_commitment_point, self.local_keys.htlc_base_key()), "Derived invalid key, peer is maliciously selecting parameters"); - let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]); - let is_local_tx = PublicKey::from_secret_key(&self.secp_ctx, &our_htlc_key) == keys.a_htlc_key; - Ok((htlc_redeemscript, self.secp_ctx.sign(&sighash, &our_htlc_key), is_local_tx)) - } - - /// 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! - fn sign_htlc_transaction(&self, tx: &mut Transaction, their_sig: &Signature, preimage: &Option, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result { - if tx.input.len() != 1 { - panic!("Tried to sign HTLC transaction that had input count != 1!"); - } - if tx.input[0].witness.len() != 0 { - panic!("Tried to re-sign HTLC transaction"); - } - - let (htlc_redeemscript, our_sig, local_tx) = self.create_htlc_tx_signature(tx, htlc, keys)?; - - 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()); - } else { - tx.input[0].witness.push(preimage.unwrap().0.to_vec()); - } - - tx.input[0].witness.push(htlc_redeemscript.into_bytes()); - - Ok(our_sig) - } - /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made. /// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return /// Ok(_) if debug assertions are turned on and preconditions are met. @@ -1477,8 +1386,6 @@ impl Channel { } } else { None }; - self.channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint); - self.their_dust_limit_satoshis = msg.dust_limit_satoshis; self.their_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000); self.their_channel_reserve_satoshis = msg.channel_reserve_satoshis; @@ -1495,26 +1402,25 @@ impl Channel { self.their_shutdown_scriptpubkey = their_shutdown_scriptpubkey; let obscure_factor = self.get_commitment_transaction_number_obscure_factor(); - self.channel_monitor.set_commitment_obscure_factor(obscure_factor); - self.channel_monitor.set_their_to_self_delay(msg.to_self_delay); + let funding_redeemscript = self.get_funding_redeemscript(); + self.channel_monitor.set_basic_channel_info(&msg.htlc_basepoint, &msg.delayed_payment_basepoint, msg.to_self_delay, funding_redeemscript, self.channel_value_satoshis, obscure_factor); self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32; Ok(()) } - fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, Transaction, Signature, TxCreationKeys), ChannelError> { + fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, LocalCommitmentTransaction, Signature, TxCreationKeys), ChannelError> { let funding_script = self.get_funding_redeemscript(); let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?; - let mut local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0; + let local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0; let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]); // They sign the "local" commitment transaction... secp_check!(self.secp_ctx.verify(&local_sighash, &sig, &self.their_funding_pubkey.unwrap()), "Invalid funding_created signature from peer"); - // ...and we sign it, allowing us to broadcast the tx if we wish - self.sign_commitment_transaction(&mut local_initial_commitment_tx, sig); + let localtx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, sig, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey.as_ref().unwrap()); let remote_keys = self.build_remote_transaction_keys()?; let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0; @@ -1522,7 +1428,7 @@ impl Channel { .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed"))?.0; // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish. - Ok((remote_initial_commitment_tx, local_initial_commitment_tx, remote_signature, local_keys)) + Ok((remote_initial_commitment_tx, localtx, remote_signature, local_keys)) } pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), ChannelError> { @@ -1556,7 +1462,6 @@ impl Channel { // Now that we're past error-generating stuff, update our local state: self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_initial_commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap()); - self.last_local_commitment_txn = vec![local_initial_commitment_tx.clone()]; self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx, local_keys, self.feerate_per_kw, Vec::new()); self.channel_state = ChannelState::FundingSent as u32; self.channel_id = funding_txo.to_channel_id(); @@ -1587,15 +1492,15 @@ impl Channel { let funding_script = self.get_funding_redeemscript(); let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?; - let mut local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0; + let local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0; let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]); // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish. secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid funding_signed signature from peer"); - self.sign_commitment_transaction(&mut local_initial_commitment_tx, &msg.signature); - self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx.clone(), local_keys, self.feerate_per_kw, Vec::new()); - self.last_local_commitment_txn = vec![local_initial_commitment_tx]; + self.channel_monitor.provide_latest_local_commitment_tx_info( + LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey.as_ref().unwrap()), + local_keys, self.feerate_per_kw, Vec::new()); self.channel_state = ChannelState::FundingSent as u32 | (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)); self.cur_local_commitment_transaction_number -= 1; @@ -1859,26 +1764,15 @@ impl Channel { return Err(ChannelError::Close("Got wrong number of HTLC signatures from remote")); } - let mut new_local_commitment_txn = Vec::with_capacity(local_commitment_tx.1 + 1); - self.sign_commitment_transaction(&mut local_commitment_tx.0, &msg.signature); - new_local_commitment_txn.push(local_commitment_tx.0.clone()); - let mut htlcs_and_sigs = Vec::with_capacity(local_commitment_tx.2.len()); for (idx, (htlc, source)) in local_commitment_tx.2.drain(..).enumerate() { if let Some(_) = htlc.transaction_output_index { - let mut htlc_tx = self.build_htlc_transaction(&local_commitment_txid, &htlc, true, &local_keys, feerate_per_kw); + let htlc_tx = self.build_htlc_transaction(&local_commitment_txid, &htlc, true, &local_keys, feerate_per_kw); let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &local_keys); log_trace!(self, "Checking HTLC tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(local_keys.b_htlc_key.serialize()), encode::serialize_hex(&htlc_tx), encode::serialize_hex(&htlc_redeemscript)); let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]); secp_check!(self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key), "Invalid HTLC tx signature from peer"); - let htlc_sig = if htlc.offered { - let htlc_sig = self.sign_htlc_transaction(&mut htlc_tx, &msg.htlc_signatures[idx], &None, &htlc, &local_keys)?; - new_local_commitment_txn.push(htlc_tx); - htlc_sig - } else { - self.create_htlc_tx_signature(&htlc_tx, &htlc, &local_keys)?.1 - }; - htlcs_and_sigs.push((htlc, Some((msg.htlc_signatures[idx], htlc_sig)), source)); + htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source)); } else { htlcs_and_sigs.push((htlc, None, source)); } @@ -1902,7 +1796,10 @@ impl Channel { } } - self.channel_monitor.provide_latest_local_commitment_tx_info(local_commitment_tx.0, local_keys, self.feerate_per_kw, htlcs_and_sigs); + + self.channel_monitor.provide_latest_local_commitment_tx_info( + LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey.as_ref().unwrap()), + local_keys, self.feerate_per_kw, htlcs_and_sigs); for htlc in self.pending_inbound_htlcs.iter_mut() { let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state { @@ -1923,7 +1820,6 @@ impl Channel { } self.cur_local_commitment_transaction_number -= 1; - self.last_local_commitment_txn = new_local_commitment_txn; // Note that if we need_our_commitment & !AwaitingRemoteRevoke we'll call // send_commitment_no_status_check() next which will reset this to RAAFirst. self.resend_order = RAACommitmentOrder::CommitmentFirst; @@ -2881,11 +2777,11 @@ impl Channel { } /// May only be called after funding has been initiated (ie is_funding_initiated() is true) - pub fn channel_monitor(&self) -> ChannelMonitor { + pub fn channel_monitor(&mut self) -> &mut ChannelMonitor { if self.channel_state < ChannelState::FundingCreated as u32 { panic!("Can't get a channel monitor until funding has been created"); } - self.channel_monitor.clone() + &mut self.channel_monitor } /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus, @@ -3681,9 +3577,7 @@ impl Channel { self.channel_state = ChannelState::ShutdownComplete as u32; self.channel_update_count += 1; - let mut res = Vec::new(); - mem::swap(&mut res, &mut self.last_local_commitment_txn); - (res, dropped_outbound_htlcs) + (self.channel_monitor.get_latest_local_commitment_txn(), dropped_outbound_htlcs) } } @@ -3873,16 +3767,6 @@ impl Writeable for Channel { self.channel_update_count.write(writer)?; self.feerate_per_kw.write(writer)?; - (self.last_local_commitment_txn.len() as u64).write(writer)?; - for tx in self.last_local_commitment_txn.iter() { - if let Err(e) = tx.consensus_encode(&mut WriterWriteAdaptor(writer)) { - match e { - encode::Error::Io(e) => return Err(e), - _ => panic!("last_local_commitment_txn must have been well-formed!"), - } - } - } - match self.last_sent_closing_fee { Some((feerate, fee, sig)) => { 1u8.write(writer)?; @@ -4041,15 +3925,6 @@ impl> ReadableArgs tx, - Err(_) => return Err(DecodeError::InvalidValue), - }); - } - let last_sent_closing_fee = match >::read(reader)? { 0 => None, 1 => Some((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?)), @@ -4132,8 +4007,6 @@ impl> ReadableArgs ChannelManager { let pending_msg_events = channel_state.pending_msg_events; channel_state.by_id.retain(|_, channel| { if channel.is_awaiting_monitor_update() { - let chan_monitor = channel.channel_monitor(); + let chan_monitor = channel.channel_monitor().clone(); if let Err(e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) { match e { ChannelMonitorUpdateErr::PermanentFailure => { @@ -3216,7 +3216,7 @@ pub struct ChannelManagerReadArgs<'a, ChanSigner: ChannelKeys> { /// /// In such cases the latest local transactions will be sent to the tx_broadcaster included in /// this struct. - pub channel_monitors: &'a HashMap, + pub channel_monitors: &'a mut HashMap, } impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable> ReadableArgs> for (Sha256dHash, ChannelManager) { @@ -3245,7 +3245,7 @@ impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable> ReadableArg let funding_txo = channel.channel_monitor().get_funding_txo().ok_or(DecodeError::InvalidValue)?; funding_txo_set.insert(funding_txo.clone()); - if let Some(monitor) = args.channel_monitors.get(&funding_txo) { + if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) { if channel.get_cur_local_commitment_transaction_number() != monitor.get_cur_local_commitment_number() || channel.get_revoked_remote_commitment_transaction_number() != monitor.get_min_seen_secret() || channel.get_cur_remote_commitment_transaction_number() != monitor.get_cur_remote_commitment_number() { @@ -3263,7 +3263,7 @@ impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable> ReadableArg } } - for (ref funding_txo, ref monitor) in args.channel_monitors.iter() { + for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() { if !funding_txo_set.contains(funding_txo) { closed_channels.push((monitor.get_latest_local_commitment_txn(), Vec::new())); } diff --git a/lightning/src/ln/channelmonitor.rs b/lightning/src/ln/channelmonitor.rs index ea84b984..b9527f59 100644 --- a/lightning/src/ln/channelmonitor.rs +++ b/lightning/src/ln/channelmonitor.rs @@ -16,7 +16,7 @@ use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction}; use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint; use bitcoin::blockdata::script::{Script, Builder}; use bitcoin::blockdata::opcodes; -use bitcoin::consensus::encode::{self, Decodable, Encodable}; +use bitcoin::consensus::encode; use bitcoin::util::hash::BitcoinHash; use bitcoin::util::bip143; @@ -31,14 +31,14 @@ use secp256k1; use ln::msgs::DecodeError; use ln::chan_utils; -use ln::chan_utils::HTLCOutputInCommitment; +use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction}; use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash}; use ln::channel::{ACCEPTED_HTLC_SCRIPT_WEIGHT, OFFERED_HTLC_SCRIPT_WEIGHT}; use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT}; use chain::transaction::OutPoint; use chain::keysinterface::SpendableOutputDescriptor; use util::logger::Logger; -use util::ser::{ReadableArgs, Readable, Writer, Writeable, WriterWriteAdaptor, U48}; +use util::ser::{ReadableArgs, Readable, Writer, Writeable, U48}; use util::{byte_utils, events}; use std::collections::{HashMap, hash_map, HashSet}; @@ -331,13 +331,12 @@ pub(crate) const ANTI_REORG_DELAY: u32 = 6; #[derive(Clone, PartialEq)] enum Storage { Local { + funding_key: SecretKey, revocation_base_key: SecretKey, htlc_base_key: SecretKey, delayed_payment_base_key: SecretKey, payment_base_key: SecretKey, shutdown_pubkey: PublicKey, - prev_latest_per_commitment_point: Option, - latest_per_commitment_point: Option, funding_info: Option<(OutPoint, Script)>, current_remote_commitment_txid: Option, prev_remote_commitment_txid: Option, @@ -352,13 +351,14 @@ enum Storage { struct LocalSignedTx { /// txid of the transaction in tx, just used to make comparison faster txid: Sha256dHash, - tx: Transaction, + tx: LocalCommitmentTransaction, revocation_key: PublicKey, a_htlc_key: PublicKey, b_htlc_key: PublicKey, delayed_payment_key: PublicKey, + per_commitment_point: PublicKey, feerate_per_kw: u64, - htlc_outputs: Vec<(HTLCOutputInCommitment, Option<(Signature, Signature)>, Option)>, + htlc_outputs: Vec<(HTLCOutputInCommitment, Option, Option)>, } #[derive(PartialEq)] @@ -571,6 +571,8 @@ pub struct ChannelMonitor { key_storage: Storage, their_htlc_base_key: Option, their_delayed_payment_base_key: Option, + funding_redeemscript: Option