X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=src%2Fln%2Fchannel.rs;h=63d8754d903e9c79412b8b993fd3645b3fb68cb7;hb=b14baa03ab20911489bee50688785f2631f0d0f1;hp=33e09448f4170f2a6e4fa70ef0f9f5a568cb938c;hpb=1993ec0d12c7503131dbb4564d6dbce29fbf1ff0;p=rust-lightning diff --git a/src/ln/channel.rs b/src/ln/channel.rs index 33e09448..63d8754d 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}; @@ -1122,8 +1120,9 @@ impl Channel { Ok(our_sig) } - /// May return an IgnoreError, but should not, and will always return Ok(_) when - /// debug_assertions are turned on + /// 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), HandleError> { // 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 @@ -1175,7 +1174,9 @@ 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()))); } }, _ => {} @@ -1215,8 +1216,9 @@ impl Channel { } } - /// May return an IgnoreError, but should not, and will always return Ok(_) when - /// debug_assertions are turned on + /// 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, HandleError> { 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"); @@ -1553,6 +1555,12 @@ impl Channel { //TODO: Check msg.cltv_expiry further? Do this in channel manager? + if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 { + if let PendingHTLCStatus::Forward(_) = pending_forward_state { + panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing"); + } + } + // Now update local state: self.next_remote_htlc_id += 1; self.pending_inbound_htlcs.push(InboundHTLCOutput { @@ -1632,13 +1640,16 @@ impl Channel { self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason)) } - pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned) -> Result<(msgs::RevokeAndACK, Option, ChannelMonitor), HandleError> { + pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &FeeEstimator) -> Result<(msgs::RevokeAndACK, Option, Option, ChannelMonitor), HandleError> { 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}); } 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}})}); } + 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}})}); + } let funding_script = self.get_funding_redeemscript(); @@ -1730,19 +1741,21 @@ impl Channel { return Err(HandleError{err: "Previous monitor update failure prevented generation of RAA", action: Some(ErrorAction::IgnoreError)}); } - let (our_commitment_signed, monitor_update) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 { + let (our_commitment_signed, monitor_update, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 { // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok - // we'll send one right away when we get the revoke_and_ack when we // free_holding_cell_htlcs(). let (msg, monitor) = self.send_commitment_no_status_check()?; - (Some(msg), monitor) - } else { (None, self.channel_monitor.clone()) }; + (Some(msg), monitor, None) + } else if !need_our_commitment { + (None, self.channel_monitor.clone(), self.maybe_propose_first_closing_signed(fee_estimator)) + } else { (None, self.channel_monitor.clone(), None) }; Ok((msgs::RevokeAndACK { channel_id: self.channel_id, per_commitment_secret: per_commitment_secret, next_per_commitment_point: next_per_commitment_point, - }, our_commitment_signed, monitor_update)) + }, our_commitment_signed, closing_signed, monitor_update)) } /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them @@ -1843,13 +1856,16 @@ 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) -> Result<(Option, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, [u8; 32], HTLCFailReason)>, 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), HandleError> { 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}); } 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}})}); } + 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}})}); + } 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 { @@ -1971,7 +1987,7 @@ impl Channel { } self.monitor_pending_forwards.append(&mut to_forward_infos); self.monitor_pending_failures.append(&mut revoked_htlcs); - return Ok((None, Vec::new(), Vec::new(), self.channel_monitor.clone())); + return Ok((None, Vec::new(), Vec::new(), None, self.channel_monitor.clone())); } match self.free_holding_cell_htlcs()? { @@ -1984,7 +2000,7 @@ impl Channel { for fail_msg in update_fail_malformed_htlcs.drain(..) { commitment_update.0.update_fail_malformed_htlcs.push(fail_msg); } - Ok((Some(commitment_update.0), to_forward_infos, revoked_htlcs, commitment_update.1)) + Ok((Some(commitment_update.0), to_forward_infos, revoked_htlcs, None, commitment_update.1)) }, None => { if require_commitment { @@ -1996,9 +2012,9 @@ impl Channel { update_fail_malformed_htlcs, update_fee: None, commitment_signed - }), to_forward_infos, revoked_htlcs, monitor_update)) + }), to_forward_infos, revoked_htlcs, None, monitor_update)) } else { - Ok((None, to_forward_infos, revoked_htlcs, self.channel_monitor.clone())) + Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), self.channel_monitor.clone())) } } } @@ -2057,6 +2073,9 @@ impl Channel { self.channel_state = ChannelState::ShutdownComplete as u32; return outbound_drops; } + // Upon reconnect we have to start the closing_signed dance over, but shutdown messages + // will be retransmitted. + self.last_sent_closing_fee = None; let mut inbound_drop_count = 0; self.pending_inbound_htlcs.retain(|htlc| { @@ -2244,7 +2263,7 @@ impl Channel { /// May panic if some calls other than message-handling calls (which will all Err immediately) /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call. - pub fn channel_reestablish(&mut self, msg: &msgs::ChannelReestablish) -> Result<(Option, Option, Option, Option, RAACommitmentOrder), ChannelError> { + pub fn channel_reestablish(&mut self, msg: &msgs::ChannelReestablish) -> Result<(Option, Option, Option, Option, RAACommitmentOrder, Option), ChannelError> { if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 { // While BOLT 2 doesn't indicate explicitly we should error this channel here, it // almost certainly indicates we are going to end up out-of-sync in some way, so we @@ -2260,9 +2279,16 @@ impl Channel { // remaining cases either succeed or ErrorMessage-fail). self.channel_state &= !(ChannelState::PeerDisconnected as u32); + let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 { + Some(msgs::Shutdown { + channel_id: self.channel_id, + scriptpubkey: self.get_closing_scriptpubkey(), + }) + } else { None }; + if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) == ChannelState::FundingSent as u32 { // Short circuit the whole handler as there is nothing we can resend them - return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst)); + return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg)); } if msg.next_local_commitment_number == 0 || msg.next_remote_commitment_number == 0 { @@ -2275,7 +2301,7 @@ impl Channel { return Ok((Some(msgs::FundingLocked { channel_id: self.channel_id(), next_per_commitment_point: next_per_commitment_point, - }), None, None, None, RAACommitmentOrder::CommitmentFirst)); + }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg)); } let required_revoke = if msg.next_remote_commitment_number == INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number { @@ -2338,11 +2364,11 @@ impl Channel { 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)), - Ok(None) => return Ok((resend_funding_locked, required_revoke, None, None, order)), + 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)), } } else { - return Ok((resend_funding_locked, required_revoke, None, None, order)); + return Ok((resend_funding_locked, required_revoke, None, None, order, shutdown_msg)); } } else if msg.next_local_commitment_number == our_next_remote_commitment_number - 1 { if required_revoke.is_some() { @@ -2356,17 +2382,20 @@ impl Channel { if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 { self.monitor_pending_commitment_signed = true; - return Ok((resend_funding_locked, None, None, None, order)); + return Ok((resend_funding_locked, None, None, None, order, shutdown_msg)); } - return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update()), None, order)); + return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update()), None, order, shutdown_msg)); } else { return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction")); } } fn maybe_propose_first_closing_signed(&mut self, fee_estimator: &FeeEstimator) -> Option { - if !self.channel_outbound || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() { + if !self.channel_outbound || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() || + self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK || + self.last_sent_closing_fee.is_some() || + self.cur_remote_commitment_transaction_number != self.cur_local_commitment_transaction_number{ return None; } @@ -2404,9 +2433,6 @@ impl Channel { return Err(ChannelError::Close("Got shutdown with remote pending HTLCs")); } } - if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 { - return Err(ChannelError::Ignore("Remote peer sent duplicate shutdown message")); - } assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0); // BOLT 2 says we must only send a scriptpubkey of certain standard forms, which are up to @@ -2436,6 +2462,7 @@ impl Channel { // We can't send our shutdown until we've committed all of our pending HTLCs, but the // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding // cell HTLCs and return them to fail the payment. + self.holding_cell_update_fee = None; let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len()); self.holding_cell_htlc_updates.retain(|htlc_update| { match htlc_update { @@ -2798,6 +2825,16 @@ 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)) | @@ -3244,9 +3281,9 @@ impl Channel { } self.channel_update_count += 1; - // We can't send our shutdown until we've committed all of our pending HTLCs, but the - // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding - // cell HTLCs and return them to fail the payment. + // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send + // our shutdown until we've committed all of the pending changes. + self.holding_cell_update_fee = None; let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len()); self.holding_cell_htlc_updates.retain(|htlc_update| { match htlc_update { @@ -3486,9 +3523,9 @@ 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!"), } } @@ -3665,7 +3702,7 @@ 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), }); @@ -3793,7 +3830,7 @@ 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; @@ -3915,7 +3952,7 @@ 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($tx_hex).unwrap()[..]); }; } @@ -3948,7 +3985,7 @@ mod tests { } chan.sign_htlc_transaction(&mut htlc_tx, &remote_signature, &preimage, &htlc, &keys).unwrap(); - assert_eq!(serialize(&htlc_tx).unwrap()[..], + assert_eq!(serialize(&htlc_tx)[..], hex::decode($tx_hex).unwrap()[..]); }; }