X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchannel.rs;h=577223c63826a0eecc3406e7a9f0f9de8276bf02;hb=10e213cf40c5b6797e7d1a8615616f79524dbbe9;hp=73683eec32680575e9a97bcc9db5b0f6f89f81a0;hpb=9dfe42cf8681afc9c3f84e0c85a4e2a30c1156a8;p=rust-lightning diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index 73683eec..577223c6 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -25,7 +25,7 @@ use bitcoin::secp256k1; use crate::ln::{PaymentPreimage, PaymentHash}; use crate::ln::features::{ChannelTypeFeatures, InitFeatures}; use crate::ln::msgs; -use crate::ln::msgs::{DecodeError, OptionalField, DataLossProtect}; +use crate::ln::msgs::DecodeError; use crate::ln::script::{self, ShutdownScript}; use crate::ln::channelmanager::{self, CounterpartyForwardingInfo, PendingHTLCStatus, HTLCSource, SentHTLCId, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT}; use crate::ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, htlc_success_tx_weight, htlc_timeout_tx_weight, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS, get_commitment_transaction_number_obscure_factor, ClosingTransaction}; @@ -35,7 +35,7 @@ use crate::chain::BestBlock; use crate::chain::chaininterface::{FeeEstimator, ConfirmationTarget, LowerBoundedFeeEstimator}; use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, LATENCY_GRACE_PERIOD_BLOCKS, CLOSED_CHANNEL_UPDATE_ID}; use crate::chain::transaction::{OutPoint, TransactionData}; -use crate::chain::keysinterface::{WriteableEcdsaChannelSigner, EntropySource, ChannelSigner, SignerProvider, NodeSigner, Recipient}; +use crate::sign::{WriteableEcdsaChannelSigner, EntropySource, ChannelSigner, SignerProvider, NodeSigner, Recipient}; use crate::events::ClosureReason; use crate::routing::gossip::NodeId; use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter}; @@ -73,6 +73,8 @@ pub struct AvailableBalances { pub outbound_capacity_msat: u64, /// The maximum value we can assign to the next outbound HTLC pub next_outbound_htlc_limit_msat: u64, + /// The minimum value we can assign to the next outbound HTLC + pub next_outbound_htlc_minimum_msat: u64, } #[derive(Debug, Clone, Copy, PartialEq)] @@ -1001,7 +1003,10 @@ impl Channel { secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes()); let shutdown_scriptpubkey = if config.channel_handshake_config.commit_upfront_shutdown_pubkey { - Some(signer_provider.get_shutdown_scriptpubkey()) + match signer_provider.get_shutdown_scriptpubkey() { + Ok(scriptpubkey) => Some(scriptpubkey), + Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get shutdown scriptpubkey".to_owned()}), + } } else { None }; if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey { @@ -1010,6 +1015,11 @@ impl Channel { } } + let destination_script = match signer_provider.get_destination_script() { + Ok(script) => script, + Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get destination script".to_owned()}), + }; + let temporary_channel_id = entropy_source.get_secure_random_bytes(); Ok(Channel { @@ -1036,7 +1046,7 @@ impl Channel { holder_signer, shutdown_scriptpubkey, - destination_script: signer_provider.get_destination_script(), + destination_script, cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER, cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER, @@ -1329,7 +1339,7 @@ impl Channel { let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() { match &msg.shutdown_scriptpubkey { - &OptionalField::Present(ref script) => { + &Some(ref script) => { // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything if script.len() == 0 { None @@ -1341,14 +1351,17 @@ impl Channel { } }, // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel - &OptionalField::Absent => { + &None => { return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned())); } } } else { None }; let shutdown_scriptpubkey = if config.channel_handshake_config.commit_upfront_shutdown_pubkey { - Some(signer_provider.get_shutdown_scriptpubkey()) + match signer_provider.get_shutdown_scriptpubkey() { + Ok(scriptpubkey) => Some(scriptpubkey), + Err(_) => return Err(ChannelError::Close("Failed to get upfront shutdown scriptpubkey".to_owned())), + } } else { None }; if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey { @@ -1357,6 +1370,11 @@ impl Channel { } } + let destination_script = match signer_provider.get_destination_script() { + Ok(script) => script, + Err(_) => return Err(ChannelError::Close("Failed to get destination script".to_owned())), + }; + let mut secp_ctx = Secp256k1::new(); secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes()); @@ -1383,7 +1401,7 @@ impl Channel { holder_signer, shutdown_scriptpubkey, - destination_script: signer_provider.get_destination_script(), + destination_script, cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER, cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER, @@ -2230,7 +2248,7 @@ impl Channel { let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() { match &msg.shutdown_scriptpubkey { - &OptionalField::Present(ref script) => { + &Some(ref script) => { // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything if script.len() == 0 { None @@ -2242,7 +2260,7 @@ impl Channel { } }, // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel - &OptionalField::Absent => { + &None => { return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned())); } } @@ -2660,6 +2678,7 @@ impl Channel { /// corner case properly. pub fn get_available_balances(&self) -> AvailableBalances { // Note that we have to handle overflow due to the above case. + let inbound_stats = self.get_inbound_pending_htlc_stats(None); let outbound_stats = self.get_outbound_pending_htlc_stats(None); let mut balance_msat = self.value_to_self_msat; @@ -2670,10 +2689,112 @@ impl Channel { } balance_msat -= outbound_stats.pending_htlcs_value_msat; - let outbound_capacity_msat = cmp::max(self.value_to_self_msat as i64 - - outbound_stats.pending_htlcs_value_msat as i64 - - self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) as i64 * 1000, - 0) as u64; + let outbound_capacity_msat = self.value_to_self_msat + .saturating_sub(outbound_stats.pending_htlcs_value_msat) + .saturating_sub( + self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) * 1000); + + let mut available_capacity_msat = outbound_capacity_msat; + + if self.is_outbound() { + // We should mind channel commit tx fee when computing how much of the available capacity + // can be used in the next htlc. Mirrors the logic in send_htlc. + // + // The fee depends on whether the amount we will be sending is above dust or not, + // and the answer will in turn change the amount itself — making it a circular + // dependency. + // This complicates the computation around dust-values, up to the one-htlc-value. + let mut real_dust_limit_timeout_sat = self.holder_dust_limit_satoshis; + if !self.opt_anchors() { + real_dust_limit_timeout_sat += self.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000; + } + + let htlc_above_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000, HTLCInitiator::LocalOffered); + let max_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_above_dust, Some(())); + let htlc_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000 - 1, HTLCInitiator::LocalOffered); + let min_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_dust, Some(())); + + // We will first subtract the fee as if we were above-dust. Then, if the resulting + // value ends up being below dust, we have this fee available again. In that case, + // match the value to right-below-dust. + let mut capacity_minus_commitment_fee_msat: i64 = (available_capacity_msat as i64) - (max_reserved_commit_tx_fee_msat as i64); + if capacity_minus_commitment_fee_msat < (real_dust_limit_timeout_sat as i64) * 1000 { + let one_htlc_difference_msat = max_reserved_commit_tx_fee_msat - min_reserved_commit_tx_fee_msat; + debug_assert!(one_htlc_difference_msat != 0); + capacity_minus_commitment_fee_msat += one_htlc_difference_msat as i64; + capacity_minus_commitment_fee_msat = cmp::min(real_dust_limit_timeout_sat as i64 * 1000 - 1, capacity_minus_commitment_fee_msat); + available_capacity_msat = cmp::max(0, cmp::min(capacity_minus_commitment_fee_msat, available_capacity_msat as i64)) as u64; + } else { + available_capacity_msat = capacity_minus_commitment_fee_msat as u64; + } + } else { + // If the channel is inbound (i.e. counterparty pays the fee), we need to make sure + // sending a new HTLC won't reduce their balance below our reserve threshold. + let mut real_dust_limit_success_sat = self.counterparty_dust_limit_satoshis; + if !self.opt_anchors() { + real_dust_limit_success_sat += self.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000; + } + + let htlc_above_dust = HTLCCandidate::new(real_dust_limit_success_sat * 1000, HTLCInitiator::LocalOffered); + let max_reserved_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_above_dust, None); + + let holder_selected_chan_reserve_msat = self.holder_selected_channel_reserve_satoshis * 1000; + let remote_balance_msat = (self.channel_value_satoshis * 1000 - self.value_to_self_msat) + .saturating_sub(inbound_stats.pending_htlcs_value_msat); + + if remote_balance_msat < max_reserved_commit_tx_fee_msat + holder_selected_chan_reserve_msat { + // If another HTLC's fee would reduce the remote's balance below the reserve limit + // we've selected for them, we can only send dust HTLCs. + available_capacity_msat = cmp::min(available_capacity_msat, real_dust_limit_success_sat * 1000 - 1); + } + } + + let mut next_outbound_htlc_minimum_msat = self.counterparty_htlc_minimum_msat; + + // If we get close to our maximum dust exposure, we end up in a situation where we can send + // between zero and the remaining dust exposure limit remaining OR above the dust limit. + // Because we cannot express this as a simple min/max, we prefer to tell the user they can + // send above the dust limit (as the router can always overpay to meet the dust limit). + let mut remaining_msat_below_dust_exposure_limit = None; + let mut dust_exposure_dust_limit_msat = 0; + + let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if self.opt_anchors() { + (self.counterparty_dust_limit_satoshis, self.holder_dust_limit_satoshis) + } else { + let dust_buffer_feerate = self.get_dust_buffer_feerate(None) as u64; + (self.counterparty_dust_limit_satoshis + dust_buffer_feerate * htlc_success_tx_weight(false) / 1000, + self.holder_dust_limit_satoshis + dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000) + }; + let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat; + if on_counterparty_dust_htlc_exposure_msat as i64 + htlc_success_dust_limit as i64 * 1000 - 1 > self.get_max_dust_htlc_exposure_msat() as i64 { + remaining_msat_below_dust_exposure_limit = + Some(self.get_max_dust_htlc_exposure_msat().saturating_sub(on_counterparty_dust_htlc_exposure_msat)); + dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_success_dust_limit * 1000); + } + + let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat; + if on_holder_dust_htlc_exposure_msat as i64 + htlc_timeout_dust_limit as i64 * 1000 - 1 > self.get_max_dust_htlc_exposure_msat() as i64 { + remaining_msat_below_dust_exposure_limit = Some(cmp::min( + remaining_msat_below_dust_exposure_limit.unwrap_or(u64::max_value()), + self.get_max_dust_htlc_exposure_msat().saturating_sub(on_holder_dust_htlc_exposure_msat))); + dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_timeout_dust_limit * 1000); + } + + if let Some(remaining_limit_msat) = remaining_msat_below_dust_exposure_limit { + if available_capacity_msat < dust_exposure_dust_limit_msat { + available_capacity_msat = cmp::min(available_capacity_msat, remaining_limit_msat); + } else { + next_outbound_htlc_minimum_msat = cmp::max(next_outbound_htlc_minimum_msat, dust_exposure_dust_limit_msat); + } + } + + available_capacity_msat = cmp::min(available_capacity_msat, + self.counterparty_max_htlc_value_in_flight_msat - outbound_stats.pending_htlcs_value_msat); + + if outbound_stats.pending_htlcs + 1 > self.counterparty_max_accepted_htlcs as u32 { + available_capacity_msat = 0; + } + AvailableBalances { inbound_capacity_msat: cmp::max(self.channel_value_satoshis as i64 * 1000 - self.value_to_self_msat as i64 @@ -2681,10 +2802,8 @@ impl Channel { - self.holder_selected_channel_reserve_satoshis as i64 * 1000, 0) as u64, outbound_capacity_msat, - next_outbound_htlc_limit_msat: cmp::max(cmp::min(outbound_capacity_msat as i64, - self.counterparty_max_htlc_value_in_flight_msat as i64 - - outbound_stats.pending_htlcs_value_msat as i64), - 0) as u64, + next_outbound_htlc_limit_msat: available_capacity_msat, + next_outbound_htlc_minimum_msat, balance_msat, } } @@ -4076,36 +4195,31 @@ impl Channel { if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_local_commitment_number == 0 { - return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned())); + return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned())); } if msg.next_remote_commitment_number > 0 { - match msg.data_loss_protect { - OptionalField::Present(ref data_loss) => { - let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx); - let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret) - .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?; - if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) { - return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned())); - } - if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number { - macro_rules! log_and_panic { - ($err_msg: expr) => { - log_error!(logger, $err_msg, log_bytes!(self.channel_id), log_pubkey!(self.counterparty_node_id)); - panic!($err_msg, log_bytes!(self.channel_id), log_pubkey!(self.counterparty_node_id)); - } - } - log_and_panic!("We have fallen behind - we have received proof that if we broadcast our counterparty is going to claim all our funds.\n\ - This implies you have restarted with lost ChannelMonitor and ChannelManager state, the first of which is a violation of the LDK chain::Watch requirements.\n\ - More specifically, this means you have a bug in your implementation that can cause loss of funds, or you are running with an old backup, which is unsafe.\n\ - If you have restored from an old backup and wish to force-close channels and return to operation, you should start up, call\n\ - ChannelManager::force_close_without_broadcasting_txn on channel {} with counterparty {} or\n\ - ChannelManager::force_close_all_channels_without_broadcasting_txn, then reconnect to peer(s).\n\ - Note that due to a long-standing bug in lnd you may have to reach out to peers running lnd-based nodes to ask them to manually force-close channels\n\ - See https://github.com/lightningdevkit/rust-lightning/issues/1565 for more info."); + let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx); + let given_secret = SecretKey::from_slice(&msg.your_last_per_commitment_secret) + .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?; + if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) { + return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned())); + } + if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number { + macro_rules! log_and_panic { + ($err_msg: expr) => { + log_error!(logger, $err_msg, log_bytes!(self.channel_id), log_pubkey!(self.counterparty_node_id)); + panic!($err_msg, log_bytes!(self.channel_id), log_pubkey!(self.counterparty_node_id)); } - }, - OptionalField::Absent => {} + } + log_and_panic!("We have fallen behind - we have received proof that if we broadcast our counterparty is going to claim all our funds.\n\ + This implies you have restarted with lost ChannelMonitor and ChannelManager state, the first of which is a violation of the LDK chain::Watch requirements.\n\ + More specifically, this means you have a bug in your implementation that can cause loss of funds, or you are running with an old backup, which is unsafe.\n\ + If you have restored from an old backup and wish to force-close channels and return to operation, you should start up, call\n\ + ChannelManager::force_close_without_broadcasting_txn on channel {} with counterparty {} or\n\ + ChannelManager::force_close_all_channels_without_broadcasting_txn, then reconnect to peer(s).\n\ + Note that due to a long-standing bug in lnd you may have to reach out to peers running lnd-based nodes to ask them to manually force-close channels\n\ + See https://github.com/lightningdevkit/rust-lightning/issues/1565 for more info."); } } @@ -4392,7 +4506,10 @@ impl Channel { Some(_) => false, None => { assert!(send_shutdown); - let shutdown_scriptpubkey = signer_provider.get_shutdown_scriptpubkey(); + let shutdown_scriptpubkey = match signer_provider.get_shutdown_scriptpubkey() { + Ok(scriptpubkey) => scriptpubkey, + Err(_) => return Err(ChannelError::Close("Failed to get shutdown scriptpubkey".to_owned())), + }; if !shutdown_scriptpubkey.is_compatible(their_features) { return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey))); } @@ -5402,7 +5519,7 @@ impl Channel { htlc_basepoint: keys.htlc_basepoint, first_per_commitment_point, channel_flags: if self.config.announced_channel {1} else {0}, - shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey { + shutdown_scriptpubkey: Some(match &self.shutdown_scriptpubkey { Some(script) => script.clone().into_inner(), None => Builder::new().into_script(), }), @@ -5468,7 +5585,7 @@ impl Channel { delayed_payment_basepoint: keys.delayed_payment_basepoint, htlc_basepoint: keys.htlc_basepoint, first_per_commitment_point, - shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey { + shutdown_scriptpubkey: Some(match &self.shutdown_scriptpubkey { Some(script) => script.clone().into_inner(), None => Builder::new().into_script(), }), @@ -5730,19 +5847,13 @@ impl Channel { // valid, and valid in fuzzing mode's arbitrary validity criteria: let mut pk = [2; 33]; pk[1] = 0xff; let dummy_pubkey = PublicKey::from_slice(&pk).unwrap(); - let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER { + let remote_last_secret = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER { let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap(); log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {} for channel {}", log_bytes!(remote_last_secret), log_bytes!(self.channel_id())); - OptionalField::Present(DataLossProtect { - your_last_per_commitment_secret: remote_last_secret, - my_current_per_commitment_point: dummy_pubkey - }) + remote_last_secret } else { log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.channel_id())); - OptionalField::Present(DataLossProtect { - your_last_per_commitment_secret: [0;32], - my_current_per_commitment_point: dummy_pubkey, - }) + [0;32] }; msgs::ChannelReestablish { channel_id: self.channel_id(), @@ -5764,7 +5875,12 @@ impl Channel { // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't // overflow here. next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1, - data_loss_protect, + your_last_per_commitment_secret: remote_last_secret, + my_current_per_commitment_point: dummy_pubkey, + // TODO(dual_funding): If we've sent `commtiment_signed` for an interactive transaction + // construction but have not received `tx_signatures` we MUST set `next_funding_txid` to the + // txid of that interactive transaction, else we MUST NOT set it. + next_funding_txid: None, } } @@ -5820,8 +5936,15 @@ impl Channel { return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned())); } - if amount_msat < self.counterparty_htlc_minimum_msat { - return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat))); + let available_balances = self.get_available_balances(); + if amount_msat < available_balances.next_outbound_htlc_minimum_msat { + return Err(ChannelError::Ignore(format!("Cannot send less than our next-HTLC minimum - {} msat", + available_balances.next_outbound_htlc_minimum_msat))); + } + + if amount_msat > available_balances.next_outbound_htlc_limit_msat { + return Err(ChannelError::Ignore(format!("Cannot send more than our next-HTLC maximum - {} msat", + available_balances.next_outbound_htlc_limit_msat))); } if (self.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 { @@ -5834,75 +5957,13 @@ impl Channel { return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned())); } - let inbound_stats = self.get_inbound_pending_htlc_stats(None); - let outbound_stats = self.get_outbound_pending_htlc_stats(None); - if outbound_stats.pending_htlcs + 1 > self.counterparty_max_accepted_htlcs as u32 { - return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs))); - } - // Check their_max_htlc_value_in_flight_msat - if outbound_stats.pending_htlcs_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat { - return Err(ChannelError::Ignore(format!("Cannot send value that would put us over the max HTLC value in flight our peer will accept ({})", self.counterparty_max_htlc_value_in_flight_msat))); - } - - let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number); - let commitment_stats = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, true, logger); - if !self.is_outbound() { - // Check that we won't violate the remote channel reserve by adding this HTLC. - let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered); - let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None); - let holder_selected_chan_reserve_msat = self.holder_selected_channel_reserve_satoshis * 1000; - if commitment_stats.remote_balance_msat < counterparty_commit_tx_fee_msat + holder_selected_chan_reserve_msat { - return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned())); - } - } - - let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if self.opt_anchors() { - (0, 0) - } else { - let dust_buffer_feerate = self.get_dust_buffer_feerate(None) as u64; - (dust_buffer_feerate * htlc_success_tx_weight(false) / 1000, - dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000) - }; - let exposure_dust_limit_success_sats = htlc_success_dust_limit + self.counterparty_dust_limit_satoshis; - if amount_msat / 1000 < exposure_dust_limit_success_sats { - let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + amount_msat; - if on_counterparty_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() { - return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx", - on_counterparty_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat()))); - } - } - - let exposure_dust_limit_timeout_sats = htlc_timeout_dust_limit + self.holder_dust_limit_satoshis; - if amount_msat / 1000 < exposure_dust_limit_timeout_sats { - let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + amount_msat; - if on_holder_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() { - return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx", - on_holder_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat()))); - } - } - - let holder_balance_msat = commitment_stats.local_balance_msat - outbound_stats.holding_cell_msat; - if holder_balance_msat < amount_msat { - return Err(ChannelError::Ignore(format!("Cannot send value that would overdraw remaining funds. Amount: {}, pending value to self {}", amount_msat, holder_balance_msat))); - } - - // `2 *` and extra HTLC are for the fee spike buffer. - let commit_tx_fee_msat = if self.is_outbound() { - let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered); - FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(())) - } else { 0 }; - if holder_balance_msat - amount_msat < commit_tx_fee_msat { - return Err(ChannelError::Ignore(format!("Cannot send value that would not leave enough to pay for fees. Pending value to self: {}. local_commit_tx_fee {}", holder_balance_msat, commit_tx_fee_msat))); - } + let need_holding_cell = (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0; + log_debug!(logger, "Pushing new outbound HTLC for {} msat {}", amount_msat, + if force_holding_cell { "into holding cell" } + else if need_holding_cell { "into holding cell as we're awaiting an RAA or monitor" } + else { "to peer" }); - // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as - // reserve for the remote to have something to claim if we misbehave) - let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000; - if holder_balance_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat { - return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat))); - } - - if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 { + if need_holding_cell { force_holding_cell = true; } @@ -6109,7 +6170,7 @@ impl Channel { /// May jump to the channel being fully shutdown (see [`Self::is_shutdown`]) in which case no /// [`ChannelMonitorUpdate`] will be returned). pub fn get_shutdown(&mut self, signer_provider: &SP, their_features: &InitFeatures, - target_feerate_sats_per_kw: Option) + target_feerate_sats_per_kw: Option, override_shutdown_script: Option) -> Result<(msgs::Shutdown, Option<&ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError> where SP::Target: SignerProvider { for htlc in self.pending_outbound_htlcs.iter() { @@ -6125,6 +6186,9 @@ impl Channel { return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()}); } } + if self.shutdown_scriptpubkey.is_some() && override_shutdown_script.is_some() { + return Err(APIError::APIMisuseError{err: "Cannot override shutdown script for a channel with one already set".to_owned()}); + } assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0); if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32) != 0 { return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?".to_owned()}); @@ -6140,7 +6204,17 @@ impl Channel { let update_shutdown_script = match self.shutdown_scriptpubkey { Some(_) => false, None if !chan_closed => { - let shutdown_scriptpubkey = signer_provider.get_shutdown_scriptpubkey(); + // use override shutdown script if provided + let shutdown_scriptpubkey = match override_shutdown_script { + Some(script) => script, + None => { + // otherwise, use the shutdown scriptpubkey provided by the signer + match signer_provider.get_shutdown_scriptpubkey() { + Ok(scriptpubkey) => scriptpubkey, + Err(_) => return Err(APIError::ChannelUnavailable{err: "Failed to get shutdown scriptpubkey".to_owned()}), + } + }, + }; if !shutdown_scriptpubkey.is_compatible(their_features) { return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() }); } @@ -7099,13 +7173,13 @@ mod tests { use crate::ln::channel::{Channel, InboundHTLCOutput, OutboundHTLCOutput, InboundHTLCState, OutboundHTLCState, HTLCCandidate, HTLCInitiator}; use crate::ln::channel::{MAX_FUNDING_SATOSHIS_NO_WUMBO, TOTAL_BITCOIN_SUPPLY_SATOSHIS, MIN_THEIR_CHAN_RESERVE_SATOSHIS}; use crate::ln::features::ChannelTypeFeatures; - use crate::ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate, MAX_VALUE_MSAT}; + use crate::ln::msgs::{ChannelUpdate, DecodeError, UnsignedChannelUpdate, MAX_VALUE_MSAT}; use crate::ln::script::ShutdownScript; use crate::ln::chan_utils; use crate::ln::chan_utils::{htlc_success_tx_weight, htlc_timeout_tx_weight}; use crate::chain::BestBlock; use crate::chain::chaininterface::{FeeEstimator, LowerBoundedFeeEstimator, ConfirmationTarget}; - use crate::chain::keysinterface::{ChannelSigner, InMemorySigner, EntropySource, SignerProvider}; + use crate::sign::{ChannelSigner, InMemorySigner, EntropySource, SignerProvider}; use crate::chain::transaction::OutPoint; use crate::routing::router::Path; use crate::util::config::UserConfig; @@ -7170,17 +7244,17 @@ mod tests { fn read_chan_signer(&self, _data: &[u8]) -> Result { panic!(); } - fn get_destination_script(&self) -> Script { + fn get_destination_script(&self) -> Result { let secp_ctx = Secp256k1::signing_only(); let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(); let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize()); - Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script() + Ok(Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()) } - fn get_shutdown_scriptpubkey(&self) -> ShutdownScript { + fn get_shutdown_scriptpubkey(&self) -> Result { let secp_ctx = Secp256k1::signing_only(); let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(); - ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key)) + Ok(ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key))) } } @@ -7400,12 +7474,7 @@ mod tests { let msg = node_b_chan.get_channel_reestablish(&&logger); assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number - match msg.data_loss_protect { - OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => { - assert_eq!(your_last_per_commitment_secret, [0; 32]); - }, - _ => panic!() - } + assert_eq!(msg.your_last_per_commitment_secret, [0; 32]); // Check that the commitment point in Node A's channel_reestablish message // is sane. @@ -7413,12 +7482,7 @@ mod tests { let msg = node_a_chan.get_channel_reestablish(&&logger); assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number - match msg.data_loss_protect { - OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => { - assert_eq!(your_last_per_commitment_secret, [0; 32]); - }, - _ => panic!() - } + assert_eq!(msg.your_last_per_commitment_secret, [0; 32]); } #[test] @@ -7609,7 +7673,7 @@ mod tests { use bitcoin::hashes::hex::FromHex; use bitcoin::hash_types::Txid; use bitcoin::secp256k1::Message; - use crate::chain::keysinterface::EcdsaChannelSigner; + use crate::sign::EcdsaChannelSigner; use crate::ln::PaymentPreimage; use crate::ln::channel::{HTLCOutputInCommitment ,TxCreationKeys}; use crate::ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};