X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=src%2Fln%2Fchannel.rs;h=e0fdcaf9080627a3dae94786adadc080707aca82;hb=6969fc997bd18d21c5a25fae34bc1eb123bf512b;hp=b9a81f6ebc0465cf34396eb44073b790fd7c3925;hpb=224fb05cc53526e7b861e746183451d3d74ad549;p=rust-lightning diff --git a/src/ln/channel.rs b/src/ln/channel.rs index b9a81f6e..e0fdcaf9 100644 --- a/src/ln/channel.rs +++ b/src/ln/channel.rs @@ -2,11 +2,9 @@ use bitcoin::blockdata::block::BlockHeader; use bitcoin::blockdata::script::{Script,Builder}; use bitcoin::blockdata::transaction::{TxIn, TxOut, Transaction, SigHashType}; use bitcoin::blockdata::opcodes; -use bitcoin::util::hash::{Sha256dHash, Hash160}; +use bitcoin::util::hash::{BitcoinHash, Sha256dHash, Hash160}; use bitcoin::util::bip143; -use bitcoin::network; -use bitcoin::network::serialize::{BitcoinHash, RawDecoder, RawEncoder}; -use bitcoin::network::encodable::{ConsensusEncodable, ConsensusDecodable}; +use bitcoin::consensus::encode::{self, Encodable, Decodable}; use secp256k1::key::{PublicKey,SecretKey}; use secp256k1::{Secp256k1,Message,Signature}; @@ -357,8 +355,9 @@ const UNCONF_THRESHOLD: u32 = 6; const BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7; //TODO? /// The amount of time we're willing to wait to claim money back to us const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 14; -const COMMITMENT_TX_BASE_WEIGHT: u64 = 724; -const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172; +/// Exposing these two constants for use in test in ChannelMonitor +pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724; +pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172; const SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT: u64 = 79; // prevout: 36, nSequence: 4, script len: 1, witness lengths: (3+1)/4, sig: 73/4, if-selector: 1, redeemScript: (6 ops + 2*33 pubkeys + 1*2 delay)/4 const B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT: u64 = 104; // prevout: 40, nSequence: 4, script len: 1, witness lengths: 3/4, sig: 73/4, pubkey: 33/4, output: 31 (TODO: Wrong? Useless?) /// Maximmum `funding_satoshis` value, according to the BOLT #2 specification @@ -368,6 +367,7 @@ pub const MAX_FUNDING_SATOSHIS: u64 = (1 << 24); /// Used to return a simple Error back to ChannelManager. Will get converted to a /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our /// channel_id in ChannelManager. +#[derive(Debug)] pub(super) enum ChannelError { Ignore(&'static str), Close(&'static str), @@ -382,11 +382,15 @@ macro_rules! secp_call { }; } -macro_rules! secp_derived_key { - ( $res: expr, $chan_id: expr ) => { - secp_call!($res, "Derived invalid key, peer is maliciously selecting parameters", $chan_id) - } +macro_rules! secp_check { + ($res: expr, $err: expr) => { + match $res { + Ok(thing) => thing, + Err(_) => return Err(ChannelError::Close($err)), + } + }; } + impl Channel { // Convert constants + channel value to limits: fn get_our_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 { @@ -438,7 +442,7 @@ impl Channel { let secp_ctx = Secp256k1::new(); let channel_monitor = ChannelMonitor::new(&chan_keys.revocation_base_key, &chan_keys.delayed_payment_base_key, - &chan_keys.htlc_base_key, BREAKDOWN_TIMEOUT, + &chan_keys.htlc_base_key, &chan_keys.payment_base_key, &keys_provider.get_shutdown_pubkey(), BREAKDOWN_TIMEOUT, keys_provider.get_destination_script(), logger.clone()); Ok(Channel { @@ -626,7 +630,7 @@ 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, BREAKDOWN_TIMEOUT, + &chan_keys.htlc_base_key, &chan_keys.payment_base_key, &keys_provider.get_shutdown_pubkey(), BREAKDOWN_TIMEOUT, 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); @@ -998,25 +1002,25 @@ impl Channel { /// our counterparty!) /// The result is a transaction which we can revoke ownership of (ie a "local" transaction) /// TODO Some magic rust shit to compile-time check this? - fn build_local_transaction_keys(&self, commitment_number: u64) -> Result { + fn build_local_transaction_keys(&self, commitment_number: u64) -> Result { let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(commitment_number)); let delayed_payment_base = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key); let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key); - Ok(secp_derived_key!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &self.their_revocation_basepoint.unwrap(), &self.their_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap()), self.channel_id())) + Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &self.their_revocation_basepoint.unwrap(), &self.their_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap()), "Local tx keys generation got bogus keys")) } #[inline] /// Creates a set of keys for build_commitment_transaction to generate a transaction which we /// will sign and send to our counterparty. - fn build_remote_transaction_keys(&self) -> Result { + fn build_remote_transaction_keys(&self) -> Result { //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we //may see payments to it! let payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key); let revocation_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key); let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key); - Ok(secp_derived_key!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &self.their_delayed_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap(), &revocation_basepoint, &payment_basepoint, &htlc_basepoint), self.channel_id())) + Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &self.their_delayed_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap(), &revocation_basepoint, &payment_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys")) } /// Gets the redeemscript for the funding transaction output (ie the funding transaction output @@ -1074,14 +1078,14 @@ impl Channel { chan_utils::build_htlc_transaction(prev_hash, feerate_per_kw, if local { self.their_to_self_delay } else { BREAKDOWN_TIMEOUT }, 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), HandleError> { + 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_derived_key!(chan_utils::derive_private_key(&self.secp_ctx, &keys.per_commitment_point, &self.local_keys.htlc_base_key), self.channel_id()); + 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 = Message::from_slice(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap(); 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)) @@ -1089,7 +1093,7 @@ impl Channel { /// Signs a transaction created by build_htlc_transaction. If the transaction is an /// HTLC-Success transaction (ie htlc.offered is false), preimate must be set! - fn sign_htlc_transaction(&self, tx: &mut Transaction, their_sig: &Signature, preimage: &Option<[u8; 32]>, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result { + fn sign_htlc_transaction(&self, tx: &mut Transaction, their_sig: &Signature, preimage: &Option<[u8; 32]>, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result { if tx.input.len() != 1 { panic!("Tried to sign HTLC transaction that had input count != 1!"); } @@ -1122,9 +1126,10 @@ impl Channel { Ok(our_sig) } - /// May return an IgnoreError, but should not, and will always return Ok(_) when - /// debug_assertions are turned on - fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: [u8; 32]) -> Result<(Option, Option), HandleError> { + /// 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. + fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: [u8; 32]) -> Result<(Option, Option), ChannelError> { // Either ChannelFunded got set (which means it wont bet unset) or there is no way any // caller thought we could have something claimed (cause we wouldn't have accepted in an // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us, @@ -1154,7 +1159,7 @@ impl Channel { } if pending_idx == std::usize::MAX { debug_assert!(false, "Unable to find a pending HTLC which matched the given HTLC ID"); - return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: Some(msgs::ErrorAction::IgnoreError)}); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); } // Now update local state: @@ -1175,7 +1180,9 @@ impl Channel { &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => { if htlc_id_arg == htlc_id { debug_assert!(false, "Tried to fulfill an HTLC we already had a holding-cell failure on"); - return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: Some(msgs::ErrorAction::IgnoreError)}); + // Return the new channel monitor in a last-ditch effort to hit the + // chain and claim the funds + return Ok((None, Some(self.channel_monitor.clone()))); } }, _ => {} @@ -1204,7 +1211,7 @@ impl Channel { }), Some(self.channel_monitor.clone()))) } - pub fn get_update_fulfill_htlc_and_commit(&mut self, htlc_id: u64, payment_preimage: [u8; 32]) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option), HandleError> { + pub fn get_update_fulfill_htlc_and_commit(&mut self, htlc_id: u64, payment_preimage: [u8; 32]) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option), ChannelError> { match self.get_update_fulfill_htlc(htlc_id, payment_preimage)? { (Some(update_fulfill_htlc), _) => { let (commitment, monitor_update) = self.send_commitment_no_status_check()?; @@ -1215,9 +1222,10 @@ impl Channel { } } - /// May return an IgnoreError, but should not, and will always return Ok(_) when - /// debug_assertions are turned on - pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result, HandleError> { + /// 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. + pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result, ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { panic!("Was asked to fail an HTLC when channel was not in an operational state"); } @@ -1229,14 +1237,14 @@ impl Channel { if let InboundHTLCState::Committed = htlc.state { } else { debug_assert!(false, "Have an inbound HTLC we tried to fail before it was fully committed to"); - return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: Some(msgs::ErrorAction::IgnoreError)}); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); } pending_idx = idx; } } if pending_idx == std::usize::MAX { debug_assert!(false, "Unable to find a pending HTLC which matched the given HTLC ID"); - return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: Some(msgs::ErrorAction::IgnoreError)}); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); } // Now update local state: @@ -1246,7 +1254,7 @@ impl Channel { &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => { if htlc_id_arg == htlc_id { debug_assert!(false, "Unable to find a pending HTLC which matched the given HTLC ID"); - return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: Some(msgs::ErrorAction::IgnoreError)}); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); } }, &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => { @@ -1277,7 +1285,7 @@ impl Channel { })) } - pub fn get_update_fail_htlc_and_commit(&mut self, htlc_id: u64, err_packet: msgs::OnionErrorPacket) -> Result, HandleError> { + pub fn get_update_fail_htlc_and_commit(&mut self, htlc_id: u64, err_packet: msgs::OnionErrorPacket) -> Result, ChannelError> { match self.get_update_fail_htlc(htlc_id, err_packet)? { Some(update_fail_htlc) => { let (commitment, monitor_update) = self.send_commitment_no_status_check()?; @@ -1373,33 +1381,36 @@ impl Channel { Ok(()) } - fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, Signature), HandleError> { + fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, Transaction, 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 local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0; + 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_sighash = Message::from_slice(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap(); - // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish. - secp_call!(self.secp_ctx.verify(&local_sighash, &sig, &self.their_funding_pubkey.unwrap()), "Invalid funding_created signature from peer", self.channel_id()); + // 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 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; let remote_sighash = Message::from_slice(&bip143::SighashComponents::new(&remote_initial_commitment_tx).sighash_all(&remote_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap(); // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish. - Ok((remote_initial_commitment_tx, self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key))) + Ok((remote_initial_commitment_tx, local_initial_commitment_tx, self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key), local_keys)) } - pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), HandleError> { + pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), ChannelError> { if self.channel_outbound { - return Err(HandleError{err: "Received funding_created for an outbound channel?", action: Some(msgs::ErrorAction::SendErrorMessage {msg: msgs::ErrorMessage {channel_id: self.channel_id, data: "Received funding_created for an outbound channel?".to_string()}})}); + return Err(ChannelError::Close("Received funding_created for an outbound channel?")); } if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) { // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT // remember the channel, so its safe to just send an error_message here and drop the // channel. - return Err(HandleError{err: "Received funding_created after we got the channel!", action: Some(msgs::ErrorAction::SendErrorMessage {msg: msgs::ErrorMessage {channel_id: self.channel_id, data: "Received funding_created after we got the channel!".to_string()}})}); + return Err(ChannelError::Close("Received funding_created after we got the channel!")); } if self.channel_monitor.get_min_seen_secret() != (1 << 48) || self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER || @@ -1411,7 +1422,7 @@ impl Channel { let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh(); self.channel_monitor.set_funding_info((funding_txo, funding_txo_script)); - let (remote_initial_commitment_tx, our_signature) = match self.funding_created_signature(&msg.signature) { + let (remote_initial_commitment_tx, local_initial_commitment_tx, our_signature, local_keys) = match self.funding_created_signature(&msg.signature) { Ok(res) => res, Err(e) => { self.channel_monitor.unset_funding_info(); @@ -1421,7 +1432,9 @@ 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.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(); self.cur_remote_commitment_transaction_number -= 1; @@ -1435,12 +1448,12 @@ impl Channel { /// Handles a funding_signed message from the remote end. /// If this call is successful, broadcast the funding transaction (and not before!) - pub fn funding_signed(&mut self, msg: &msgs::FundingSigned) -> Result { + pub fn funding_signed(&mut self, msg: &msgs::FundingSigned) -> Result { if !self.channel_outbound { - return Err(HandleError{err: "Received funding_signed for an inbound channel?", action: None}); + return Err(ChannelError::Close("Received funding_signed for an inbound channel?")); } if self.channel_state != ChannelState::FundingCreated as u32 { - return Err(HandleError{err: "Received funding_signed in strange state!", action: None}); + return Err(ChannelError::Close("Received funding_signed in strange state!")); } if self.channel_monitor.get_min_seen_secret() != (1 << 48) || self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER - 1 || @@ -1455,7 +1468,7 @@ impl Channel { let local_sighash = Message::from_slice(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap(); // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish. - secp_call!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid funding_signed signature from peer", self.channel_id()); + 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()); @@ -1638,22 +1651,24 @@ impl Channel { self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason)) } - pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &FeeEstimator) -> Result<(msgs::RevokeAndACK, Option, Option, ChannelMonitor), HandleError> { + pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &FeeEstimator) -> Result<(msgs::RevokeAndACK, Option, Option, ChannelMonitor), ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(HandleError{err: "Got commitment signed message when channel was not in an operational state", action: None}); + return Err(ChannelError::Close("Got commitment signed message when channel was not in an operational state")); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(HandleError{err: "Peer sent commitment_signed when we needed a channel_reestablish", action: Some(msgs::ErrorAction::SendErrorMessage{msg: msgs::ErrorMessage{data: "Peer sent commitment_signed when we needed a channel_reestablish".to_string(), channel_id: msg.channel_id}})}); + return Err(ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish")); } if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() { - return Err(HandleError{err: "Peer sent commitment_signed after we'd started exchanging closing_signeds", action: Some(msgs::ErrorAction::SendErrorMessage{msg: msgs::ErrorMessage{data: "Peer sent commitment_signed after we'd started exchanging closing_signeds".to_string(), channel_id: msg.channel_id}})}); + return Err(ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds")); } let funding_script = self.get_funding_redeemscript(); let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?; + let mut update_fee = false; let feerate_per_kw = if !self.channel_outbound && self.pending_update_fee.is_some() { + update_fee = true; self.pending_update_fee.unwrap() } else { self.feerate_per_kw @@ -1662,10 +1677,20 @@ impl Channel { let mut local_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, feerate_per_kw); let local_commitment_txid = local_commitment_tx.0.txid(); let local_sighash = Message::from_slice(&bip143::SighashComponents::new(&local_commitment_tx.0).sighash_all(&local_commitment_tx.0.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap(); - secp_call!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid commitment tx signature from peer", self.channel_id()); + secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid commitment tx signature from peer"); + + //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction + if update_fee { + let num_htlcs = local_commitment_tx.1.len(); + let total_fee: u64 = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000; + + if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + self.their_channel_reserve_satoshis { + return Err(ChannelError::Close("Funding remote cannot afford proposed new fee")); + } + } if msg.htlc_signatures.len() != local_commitment_tx.1.len() { - return Err(HandleError{err: "Got wrong number of HTLC signatures from remote", action: None}); + 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.len() + 1); @@ -1677,7 +1702,7 @@ impl Channel { let mut 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); let htlc_sighash = Message::from_slice(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap(); - secp_call!(self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key), "Invalid HTLC tx siganture from peer", self.channel_id()); + 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); @@ -1705,6 +1730,7 @@ impl Channel { } } } + if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 { // This is a response to our post-monitor-failed unfreeze messages, so we can clear the // monitor_pending_order requirement as we won't re-send the monitor_pending messages. @@ -1736,7 +1762,7 @@ impl Channel { if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 { self.monitor_pending_revoke_and_ack = true; self.monitor_pending_commitment_signed |= need_our_commitment; - return Err(HandleError{err: "Previous monitor update failure prevented generation of RAA", action: Some(ErrorAction::IgnoreError)}); + return Err(ChannelError::Ignore("Previous monitor update failure prevented generation of RAA")); } let (our_commitment_signed, monitor_update, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 { @@ -1758,7 +1784,7 @@ impl Channel { /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them /// fulfilling or failing the last pending HTLC) - fn free_holding_cell_htlcs(&mut self) -> Result, HandleError> { + fn free_holding_cell_htlcs(&mut self) -> Result, ChannelError> { assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0); if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() { let mut htlc_updates = Vec::new(); @@ -1789,7 +1815,7 @@ impl Channel { match self.get_update_fulfill_htlc(htlc_id, payment_preimage) { Ok(update_fulfill_msg_option) => update_fulfill_htlcs.push(update_fulfill_msg_option.0.unwrap()), Err(e) => { - if let Some(msgs::ErrorAction::IgnoreError) = e.action {} + if let ChannelError::Ignore(_) = e {} else { panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC"); } @@ -1800,7 +1826,7 @@ impl Channel { match self.get_update_fail_htlc(htlc_id, err_packet.clone()) { Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()), Err(e) => { - if let Some(msgs::ErrorAction::IgnoreError) = e.action {} + if let ChannelError::Ignore(_) = e {} else { panic!("Got a non-IgnoreError action trying to fail holding cell HTLC"); } @@ -1854,23 +1880,24 @@ impl Channel { /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail, /// generating an appropriate error *after* the channel state has been updated based on the /// revoke_and_ack message. - pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &FeeEstimator) -> Result<(Option, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, [u8; 32], HTLCFailReason)>, Option, ChannelMonitor), HandleError> { + pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &FeeEstimator) -> Result<(Option, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, [u8; 32], HTLCFailReason)>, Option, ChannelMonitor), ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(HandleError{err: "Got revoke/ACK message when channel was not in an operational state", action: None}); + return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state")); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(HandleError{err: "Peer sent revoke_and_ack when we needed a channel_reestablish", action: Some(msgs::ErrorAction::SendErrorMessage{msg: msgs::ErrorMessage{data: "Peer sent revoke_and_ack when we needed a channel_reestablish".to_string(), channel_id: msg.channel_id}})}); + return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish")); } if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() { - return Err(HandleError{err: "Peer sent revoke_and_ack after we'd started exchanging closing_signeds", action: Some(msgs::ErrorAction::SendErrorMessage{msg: msgs::ErrorMessage{data: "Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_string(), channel_id: msg.channel_id}})}); + return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds")); } if let Some(their_prev_commitment_point) = self.their_prev_commitment_point { - if PublicKey::from_secret_key(&self.secp_ctx, &secp_call!(SecretKey::from_slice(&self.secp_ctx, &msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret", self.channel_id())) != their_prev_commitment_point { - return Err(HandleError{err: "Got a revoke commitment secret which didn't correspond to their current pubkey", action: None}); + if PublicKey::from_secret_key(&self.secp_ctx, &secp_check!(SecretKey::from_slice(&self.secp_ctx, &msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret")) != their_prev_commitment_point { + return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey")); } } - self.channel_monitor.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret, Some((self.cur_remote_commitment_transaction_number - 1, msg.next_per_commitment_point)))?; + self.channel_monitor.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret) + .map_err(|e| ChannelError::Close(e.0))?; // Update state now that we've passed all the can-fail calls... // (note that we may still fail to generate the new commitment_signed message, but that's @@ -2047,7 +2074,7 @@ impl Channel { }) } - pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64) -> Result, HandleError> { + pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64) -> Result, ChannelError> { match self.send_update_fee(feerate_per_kw) { Some(update_fee) => { let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?; @@ -2188,7 +2215,6 @@ impl Channel { return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish")); } Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw)?; - self.pending_update_fee = Some(msg.feerate_per_kw as u64); self.channel_update_count += 1; Ok(()) @@ -2353,15 +2379,8 @@ impl Channel { // have received some updates while we were disconnected. Free the holding cell // now! match self.free_holding_cell_htlcs() { - Err(e) => { - if let &Some(msgs::ErrorAction::DisconnectPeer{msg: Some(_)}) = &e.action { - return Err(ChannelError::Close(e.err)); - } else if let &Some(msgs::ErrorAction::SendErrorMessage{msg: _}) = &e.action { - return Err(ChannelError::Close(e.err)); - } else { - panic!("Got non-channel-failing result from free_holding_cell_htlcs"); - } - }, + Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)), + Err(ChannelError::Ignore(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"), Ok(Some((commitment_update, channel_monitor))) => return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(channel_monitor), order, shutdown_msg)), Ok(None) => return Ok((resend_funding_locked, required_revoke, None, None, order, shutdown_msg)), } @@ -2823,6 +2842,16 @@ impl Channel { self.channel_update_count += 1; return Err(HandleError{err: "funding tx had wrong script/value", action: Some(ErrorAction::DisconnectPeer{msg: None})}); } else { + if self.channel_outbound { + for input in tx.input.iter() { + if input.witness.is_empty() { + // We generated a malleable funding transaction, implying we've + // just exposed ourselves to funds loss to our counterparty. + #[cfg(not(feature = "fuzztarget"))] + panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!"); + } + } + } self.funding_tx_confirmations = 1; self.short_channel_id = Some(((height as u64) << (5*8)) | ((*index_in_block as u64) << (2*8)) | @@ -2924,7 +2953,7 @@ impl Channel { } } - fn get_outbound_funding_created_signature(&mut self) -> Result<(Signature, Transaction), HandleError> { + fn get_outbound_funding_created_signature(&mut self) -> Result<(Signature, Transaction), ChannelError> { let funding_script = self.get_funding_redeemscript(); let remote_keys = self.build_remote_transaction_keys()?; @@ -2941,7 +2970,7 @@ impl Channel { /// or if called on an inbound channel. /// Note that channel_id changes during this call! /// Do NOT broadcast the funding transaction until after a successful funding_signed call! - pub fn get_outbound_funding_created(&mut self, funding_txo: OutPoint) -> Result<(msgs::FundingCreated, ChannelMonitor), HandleError> { + pub fn get_outbound_funding_created(&mut self, funding_txo: OutPoint) -> Result<(msgs::FundingCreated, ChannelMonitor), ChannelError> { if !self.channel_outbound { panic!("Tried to create outbound funding_created message on an inbound channel!"); } @@ -2960,7 +2989,7 @@ impl Channel { let (our_signature, commitment_tx) = match self.get_outbound_funding_created_signature() { Ok(res) => res, Err(e) => { - log_error!(self, "Got bad signatures: {}!", e.err); + log_error!(self, "Got bad signatures: {:?}!", e); self.channel_monitor.unset_funding_info(); return Err(e); } @@ -2969,7 +2998,7 @@ impl Channel { let temporary_channel_id = self.channel_id; // Now that we're past error-generating stuff, update our local state: - self.channel_monitor.provide_latest_remote_commitment_tx_info(&commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number); + self.channel_monitor.provide_latest_remote_commitment_tx_info(&commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap()); self.channel_state = ChannelState::FundingCreated as u32; self.channel_id = funding_txo.to_channel_id(); self.cur_remote_commitment_transaction_number -= 1; @@ -3043,16 +3072,16 @@ impl Channel { /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed. /// You MUST call send_commitment prior to any other calls on this Channel - pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result, HandleError> { + pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result, ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) { - return Err(HandleError{err: "Cannot send HTLC until channel is fully established and we haven't started shutting down", action: None}); + return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down")); } if amount_msat > self.channel_value_satoshis * 1000 { - return Err(HandleError{err: "Cannot send more than the total value of the channel", action: None}); + return Err(ChannelError::Ignore("Cannot send more than the total value of the channel")); } if amount_msat < self.their_htlc_minimum_msat { - return Err(HandleError{err: "Cannot send less than their minimum HTLC value", action: None}); + return Err(ChannelError::Ignore("Cannot send less than their minimum HTLC value")); } if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 { @@ -3062,17 +3091,17 @@ impl Channel { // disconnected during the time the previous hop was doing the commitment dance we may // end up getting here after the forwarding delay. In any case, returning an // IgnoreError will get ChannelManager to do the right thing and fail backwards now. - return Err(HandleError{err: "Cannot send an HTLC while disconnected/frozen for channel monitor update", action: Some(ErrorAction::IgnoreError)}); + return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update")); } let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats(); if outbound_htlc_count + 1 > self.their_max_accepted_htlcs as u32 { - return Err(HandleError{err: "Cannot push more than their max accepted HTLCs", action: None}); + return Err(ChannelError::Ignore("Cannot push more than their max accepted HTLCs")); } //TODO: Spec is unclear if this is per-direction or in total (I assume per direction): // Check their_max_htlc_value_in_flight_msat if htlc_outbound_value_msat + amount_msat > self.their_max_htlc_value_in_flight_msat { - return Err(HandleError{err: "Cannot send value that would put us over our max HTLC value in flight", action: None}); + return Err(ChannelError::Ignore("Cannot send value that would put us over our max HTLC value in flight")); } let mut holding_cell_outbound_amount_msat = 0; @@ -3088,7 +3117,7 @@ impl Channel { // Check self.their_channel_reserve_satoshis (the amount we must keep as // reserve for them to have something to claim if we misbehave) if self.value_to_self_msat < self.their_channel_reserve_satoshis * 1000 + amount_msat + holding_cell_outbound_amount_msat + htlc_outbound_value_msat { - return Err(HandleError{err: "Cannot send value that would put us over our reserve value", action: None}); + return Err(ChannelError::Ignore("Cannot send value that would put us over our reserve value")); } //TODO: Check cltv_expiry? Do this in channel manager? @@ -3134,7 +3163,7 @@ impl Channel { /// Always returns a Channel-failing HandleError::action if an immediately-preceding (read: the /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err. /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc. - pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), HandleError> { + pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { panic!("Cannot create commitment tx until channel is fully established"); } @@ -3160,7 +3189,7 @@ impl Channel { self.send_commitment_no_status_check() } /// Only fails in case of bad keys - fn send_commitment_no_status_check(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), HandleError> { + fn send_commitment_no_status_check(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), ChannelError> { // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we // fail to generate this, we still are at least at a position where upgrading their status // is acceptable. @@ -3181,7 +3210,7 @@ impl Channel { match self.send_commitment_no_state_update() { Ok((res, remote_commitment_tx)) => { // Update state now that we've passed all the can-fail calls... - self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_commitment_tx.0, remote_commitment_tx.1, self.cur_remote_commitment_transaction_number); + self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_commitment_tx.0, remote_commitment_tx.1, self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap()); self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32; Ok((res, self.channel_monitor.clone())) }, @@ -3191,7 +3220,7 @@ impl Channel { /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation /// when we shouldn't change HTLC/channel state. - fn send_commitment_no_state_update(&self) -> Result<(msgs::CommitmentSigned, (Transaction, Vec)), HandleError> { + fn send_commitment_no_state_update(&self) -> Result<(msgs::CommitmentSigned, (Transaction, Vec)), ChannelError> { let funding_script = self.get_funding_redeemscript(); let mut feerate_per_kw = self.feerate_per_kw; @@ -3213,7 +3242,7 @@ impl Channel { let htlc_tx = self.build_htlc_transaction(&remote_commitment_txid, htlc, false, &remote_keys, feerate_per_kw); let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &remote_keys); let htlc_sighash = Message::from_slice(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap(); - let our_htlc_key = secp_derived_key!(chan_utils::derive_private_key(&self.secp_ctx, &remote_keys.per_commitment_point, &self.local_keys.htlc_base_key), self.channel_id()); + let our_htlc_key = secp_check!(chan_utils::derive_private_key(&self.secp_ctx, &remote_keys.per_commitment_point, &self.local_keys.htlc_base_key), "Derived invalid key, peer is maliciously selecting parameters"); htlc_sigs.push(self.secp_ctx.sign(&htlc_sighash, &our_htlc_key)); } @@ -3228,7 +3257,7 @@ impl Channel { /// to send to the remote peer in one go. /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for /// more info. - pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result, HandleError> { + pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result, ChannelError> { match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? { Some(update_add_htlc) => { let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?; @@ -3511,9 +3540,9 @@ impl Writeable for Channel { (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 RawEncoder::new(WriterWriteAdaptor(writer))) { + if let Err(e) = tx.consensus_encode(&mut WriterWriteAdaptor(writer)) { match e { - network::serialize::Error::Io(e) => return Err(e), + encode::Error::Io(e) => return Err(e), _ => panic!("last_local_commitment_txn must have been well-formed!"), } } @@ -3690,7 +3719,7 @@ impl ReadableArgs> for Channel { let last_local_commitment_txn_count: u64 = Readable::read(reader)?; let mut last_local_commitment_txn = Vec::with_capacity(cmp::min(last_local_commitment_txn_count as usize, OUR_MAX_HTLCS as usize*2 + 1)); for _ in 0..last_local_commitment_txn_count { - last_local_commitment_txn.push(match Transaction::consensus_decode(&mut RawDecoder::new(reader.by_ref())) { + last_local_commitment_txn.push(match Transaction::consensus_decode(reader.by_ref()) { Ok(tx) => tx, Err(_) => return Err(DecodeError::InvalidValue), }); @@ -3818,7 +3847,7 @@ impl ReadableArgs> for Channel { mod tests { use bitcoin::util::hash::{Sha256dHash, Hash160}; use bitcoin::util::bip143; - use bitcoin::network::serialize::serialize; + use bitcoin::consensus::encode::serialize; use bitcoin::blockdata::script::{Script, Builder}; use bitcoin::blockdata::transaction::Transaction; use bitcoin::blockdata::opcodes; @@ -3940,7 +3969,7 @@ mod tests { chan.sign_commitment_transaction(&mut unsigned_tx.0, &their_signature); - assert_eq!(serialize(&unsigned_tx.0).unwrap()[..], + assert_eq!(serialize(&unsigned_tx.0)[..], hex::decode($tx_hex).unwrap()[..]); }; } @@ -3973,7 +4002,7 @@ mod tests { } chan.sign_htlc_transaction(&mut htlc_tx, &remote_signature, &preimage, &htlc, &keys).unwrap(); - assert_eq!(serialize(&htlc_tx).unwrap()[..], + assert_eq!(serialize(&htlc_tx)[..], hex::decode($tx_hex).unwrap()[..]); }; }