X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchannel.rs;h=9a5fd0422228e1e46f4bdd3d27c6cb1c246575a8;hb=b3d0a8dd4e16b7ea89a53096d22a631959aa622f;hp=4795a2524baff9dfc6e26d4481eb90d5d9d71740;hpb=9d49c5c1a174bf807ed04421f0f08578b569448c;p=rust-lightning diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index 4795a252..9a5fd042 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -63,6 +63,21 @@ pub struct ChannelValueStat { pub counterparty_dust_limit_msat: u64, } +#[derive(Clone, Copy, PartialEq)] +enum FeeUpdateState { + // Inbound states mirroring InboundHTLCState + RemoteAnnounced, + AwaitingRemoteRevokeToAnnounce, + // Note that we do not have a AwaitingAnnouncedRemoteRevoke variant here as it is universally + // handled the same as `Committed`, with the only exception in `InboundHTLCState` being the + // distinction of when we allow ourselves to forward the HTLC. Because we aren't "forwarding" + // the fee update anywhere, we can simply consider the fee update `Committed` immediately + // instead of setting it to AwaitingAnnouncedRemoteRevoke. + + // Outbound state can only be `LocalAnnounced` or `Committed` + Outbound, +} + enum InboundHTLCRemovalReason { FailRelay(msgs::OnionErrorPacket), FailMalformed(([u8; 32], u16)), @@ -420,7 +435,7 @@ pub(super) struct Channel { // revoke_and_ack is received and new commitment_signed is generated to be // sent to the funder. Otherwise, the pending value is removed when receiving // commitment_signed. - pending_update_fee: Option, + pending_update_fee: Option<(u32, FeeUpdateState)>, // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack // is received. holding_cell_update_fee is updated when there are additional @@ -1003,10 +1018,10 @@ impl Channel { /// which peer generated this transaction and "to whom" this transaction flows. /// Returns (the transaction info, the number of HTLC outputs which were present in the /// transaction, the list of HTLCs which were not ignored when building the transaction). - /// Note that below-dust HTLCs are included in the third return value, but not the second, and - /// sources are provided only for outbound HTLCs in the third return value. + /// Note that below-dust HTLCs are included in the fourth return value, but not the third, and + /// sources are provided only for outbound HTLCs in the fourth return value. #[inline] - fn build_commitment_transaction(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, feerate_per_kw: u32, logger: &L) -> (CommitmentTransaction, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger { + fn build_commitment_transaction(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, logger: &L) -> (CommitmentTransaction, u32, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger { let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new(); let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len(); let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs); @@ -1016,6 +1031,19 @@ impl Channel { let mut local_htlc_total_msat = 0; let mut value_to_self_msat_offset = 0; + let mut feerate_per_kw = self.feerate_per_kw; + if let Some((feerate, update_state)) = self.pending_update_fee { + if match update_state { + // Note that these match the inclusion criteria when scanning + // pending_inbound_htlcs below. + FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local }, + FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local }, + FeeUpdateState::Outbound => { assert!(self.is_outbound()); generated_by_local }, + } { + feerate_per_kw = feerate; + } + } + log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...", commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number), get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()), @@ -1176,7 +1204,7 @@ impl Channel { htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap()); htlcs_included.append(&mut included_dust_htlcs); - (tx, num_nondust_htlcs, htlcs_included) + (tx, feerate_per_kw, num_nondust_htlcs, htlcs_included) } #[inline] @@ -1229,6 +1257,7 @@ impl Channel { assert!(self.pending_inbound_htlcs.is_empty()); assert!(self.pending_outbound_htlcs.is_empty()); + assert!(self.pending_update_fee.is_none()); let mut txouts: Vec<(TxOut, ())> = Vec::new(); let mut total_fee_satoshis = proposed_total_fee_satoshis; @@ -1654,7 +1683,7 @@ impl Channel { let funding_script = self.get_funding_redeemscript(); let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?; - let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, self.feerate_per_kw, logger).0; + let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger).0; { let trusted_tx = initial_commitment_tx.trust(); let initial_commitment_bitcoin_tx = trusted_tx.built_transaction(); @@ -1668,7 +1697,7 @@ impl Channel { } let counterparty_keys = self.build_remote_transaction_keys()?; - let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0; + let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0; let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust(); let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction(); @@ -1776,7 +1805,7 @@ impl Channel { let funding_script = self.get_funding_redeemscript(); let counterparty_keys = self.build_remote_transaction_keys()?; - let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0; + let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0; let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust(); let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction(); @@ -1784,7 +1813,7 @@ impl Channel { log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction)); let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?; - let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, self.feerate_per_kw, logger).0; + let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).0; { let trusted_tx = initial_commitment_tx.trust(); let initial_commitment_bitcoin_tx = trusted_tx.built_transaction(); @@ -2355,16 +2384,8 @@ impl Channel { let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?; - let mut update_fee = false; - let feerate_per_kw = if !self.is_outbound() && self.pending_update_fee.is_some() { - update_fee = true; - self.pending_update_fee.unwrap() - } else { - self.feerate_per_kw - }; - - let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid) = { - let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, feerate_per_kw, logger); + let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid, feerate_per_kw) = { + let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger); let commitment_txid = { let trusted_tx = commitment_tx.0.trust(); let bitcoin_tx = trusted_tx.built_transaction(); @@ -2379,12 +2400,17 @@ impl Channel { } bitcoin_tx.txid }; - let htlcs_cloned: Vec<_> = commitment_tx.2.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect(); - (commitment_tx.1, htlcs_cloned, commitment_tx.0, commitment_txid) + let htlcs_cloned: Vec<_> = commitment_tx.3.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect(); + (commitment_tx.2, htlcs_cloned, commitment_tx.0, commitment_txid, commitment_tx.1) }; + // If our counterparty updated the channel fee in this commitment transaction, check that + // they can actually afford the new fee now. + let update_fee = if let Some((_, update_state)) = self.pending_update_fee { + update_state == FeeUpdateState::RemoteAnnounced + } else { false }; + if update_fee { debug_assert!(!self.is_outbound()); } let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000; - //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 counterparty_reserve_we_require = Channel::::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis); if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require { @@ -2448,16 +2474,10 @@ impl Channel { // Update state now that we've passed all the can-fail calls... let mut need_commitment = false; - if !self.is_outbound() { - if let Some(fee_update) = self.pending_update_fee { - self.feerate_per_kw = fee_update; - // We later use the presence of pending_update_fee to indicate we should generate a - // commitment_signed upon receipt of revoke_and_ack, so we can only set it to None - // if we're not awaiting a revoke (ie will send a commitment_signed now). - if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) == 0 { - need_commitment = true; - self.pending_update_fee = None; - } + if let &mut Some((_, ref mut update_state)) = &mut self.pending_update_fee { + if *update_state == FeeUpdateState::RemoteAnnounced { + *update_state = FeeUpdateState::AwaitingRemoteRevokeToAnnounce; + need_commitment = true; } } @@ -2638,8 +2658,9 @@ impl Channel { if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() { return Ok((None, htlcs_to_fail)); } - let update_fee = if let Some(feerate) = self.holding_cell_update_fee { - self.pending_update_fee = self.holding_cell_update_fee.take(); + let update_fee = if let Some(feerate) = self.holding_cell_update_fee.take() { + assert!(self.is_outbound()); + self.pending_update_fee = Some((feerate, FeeUpdateState::Outbound)); Some(msgs::UpdateFee { channel_id: self.channel_id, feerate_per_kw: feerate as u32, @@ -2823,21 +2844,22 @@ impl Channel { } self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64; - if self.is_outbound() { - if let Some(feerate) = self.pending_update_fee.take() { - self.feerate_per_kw = feerate; - } - } else { - if let Some(feerate) = self.pending_update_fee { - // Because a node cannot send two commitment_signeds in a row without getting a - // revoke_and_ack from us (as it would otherwise not know the per_commitment_point - // it should use to create keys with) and because a node can't send a - // commitment_signed without changes, checking if the feerate is equal to the - // pending feerate update is sufficient to detect require_commitment. - if feerate == self.feerate_per_kw { + if let Some((feerate, update_state)) = self.pending_update_fee { + match update_state { + FeeUpdateState::Outbound => { + debug_assert!(self.is_outbound()); + log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate); + self.feerate_per_kw = feerate; + self.pending_update_fee = None; + }, + FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); }, + FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { + debug_assert!(!self.is_outbound()); + log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate); require_commitment = true; + self.feerate_per_kw = feerate; self.pending_update_fee = None; - } + }, } } @@ -2927,7 +2949,7 @@ impl Channel { } debug_assert!(self.pending_update_fee.is_none()); - self.pending_update_fee = Some(feerate_per_kw); + self.pending_update_fee = Some((feerate_per_kw, FeeUpdateState::Outbound)); Some(msgs::UpdateFee { channel_id: self.channel_id, @@ -2988,6 +3010,13 @@ impl Channel { }); self.next_counterparty_htlc_id -= inbound_drop_count; + if let Some((_, update_state)) = self.pending_update_fee { + if update_state == FeeUpdateState::RemoteAnnounced { + debug_assert!(!self.is_outbound()); + self.pending_update_fee = None; + } + } + for htlc in self.pending_outbound_htlcs.iter_mut() { if let OutboundHTLCState::RemoteRemoved(_) = htlc.state { // They sent us an update to remove this but haven't yet sent the corresponding @@ -3082,7 +3111,7 @@ impl Channel { return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned())); } Channel::::check_remote_fee(fee_estimator, msg.feerate_per_kw)?; - self.pending_update_fee = Some(msg.feerate_per_kw); + self.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced)); self.update_time_counter += 1; Ok(()) } @@ -3148,7 +3177,7 @@ impl Channel { let update_fee = if self.is_outbound() && self.pending_update_fee.is_some() { Some(msgs::UpdateFee { channel_id: self.channel_id(), - feerate_per_kw: self.pending_update_fee.unwrap(), + feerate_per_kw: self.pending_update_fee.unwrap().0, }) } else { None }; @@ -4056,7 +4085,7 @@ impl Channel { /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created) fn get_outbound_funding_created_signature(&mut self, logger: &L) -> Result where L::Target: Logger { let counterparty_keys = self.build_remote_transaction_keys()?; - let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0; + let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0; Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx) .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0) } @@ -4413,7 +4442,7 @@ impl Channel { if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) { panic!("Cannot create commitment tx while awaiting monitor update unfreeze, as send_htlc will have returned an Err so a send_commitment precondition has been violated"); } - let mut have_updates = self.pending_update_fee.is_some(); + let mut have_updates = self.is_outbound() && self.pending_update_fee.is_some(); for htlc in self.pending_outbound_htlcs.iter() { if let OutboundHTLCState::LocalAnnounced(_) = htlc.state { have_updates = true; @@ -4451,6 +4480,13 @@ impl Channel { htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason); } } + if let Some((feerate, update_state)) = self.pending_update_fee { + if update_state == FeeUpdateState::AwaitingRemoteRevokeToAnnounce { + debug_assert!(!self.is_outbound()); + self.feerate_per_kw = feerate; + self.pending_update_fee = None; + } + } self.resend_order = RAACommitmentOrder::RevokeAndACKFirst; let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) { @@ -4480,15 +4516,9 @@ 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, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger { - let mut feerate_per_kw = self.feerate_per_kw; - if let Some(feerate) = self.pending_update_fee { - if self.is_outbound() { - feerate_per_kw = feerate; - } - } - let counterparty_keys = self.build_remote_transaction_keys()?; - let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, feerate_per_kw, logger); + let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger); + let feerate_per_kw = counterparty_commitment_tx.1; let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid(); let (signature, htlc_signatures); @@ -4503,7 +4533,7 @@ impl Channel { && info.next_holder_htlc_id == self.next_holder_htlc_id && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id && info.feerate == self.feerate_per_kw { - let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.1); + let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.2); assert_eq!(actual_fee, info.fee); } } @@ -4511,8 +4541,8 @@ impl Channel { } { - let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.2.len()); - for &(ref htlc, _) in counterparty_commitment_tx.2.iter() { + let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.3.len()); + for &(ref htlc, _) in counterparty_commitment_tx.3.iter() { htlcs.push(htlc); } @@ -4539,7 +4569,7 @@ impl Channel { channel_id: self.channel_id, signature, htlc_signatures, - }, (counterparty_commitment_txid, counterparty_commitment_tx.2))) + }, (counterparty_commitment_txid, counterparty_commitment_tx.3))) } /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction @@ -4880,7 +4910,14 @@ impl Writeable for Channel { fail_reason.write(writer)?; } - self.pending_update_fee.write(writer)?; + if self.is_outbound() { + self.pending_update_fee.map(|(a, _)| a).write(writer)?; + } else if let Some((feerate, FeeUpdateState::AwaitingRemoteRevokeToAnnounce)) = self.pending_update_fee { + // As for inbound HTLCs, if the update was only announced and never committed, drop it. + Some(feerate).write(writer)?; + } else { + None::.write(writer)?; + } self.holding_cell_update_fee.write(writer)?; self.next_holder_htlc_id.write(writer)?; @@ -5095,7 +5132,8 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?)); } - let pending_update_fee = Readable::read(reader)?; + let pending_update_fee_value: Option = Readable::read(reader)?; + let holding_cell_update_fee = Readable::read(reader)?; let next_holder_htlc_id = Readable::read(reader)?; @@ -5147,7 +5185,7 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel _ => return Err(DecodeError::InvalidValue), }; - let channel_parameters = Readable::read(reader)?; + let channel_parameters: ChannelTransactionParameters = Readable::read(reader)?; let funding_transaction = Readable::read(reader)?; let counterparty_cur_commitment_point = Readable::read(reader)?; @@ -5170,6 +5208,16 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel } } + let pending_update_fee = if let Some(feerate) = pending_update_fee_value { + Some((feerate, if channel_parameters.is_outbound_from_holder { + FeeUpdateState::Outbound + } else { + FeeUpdateState::AwaitingRemoteRevokeToAnnounce + })) + } else { + None + }; + let mut announcement_sigs = None; read_tlv_fields!(reader, { (0, announcement_sigs, option), @@ -5708,9 +5756,9 @@ mod tests { $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), * } ) => { { let (commitment_tx, htlcs): (_, Vec) = { - let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, chan.feerate_per_kw, &logger); + let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger); - let htlcs = res.2.drain(..) + let htlcs = res.3.drain(..) .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None }) .collect(); (res.0, htlcs)