RemoteOffered,
}
-/// An enum gathering stats on pending HTLCs, either inbound or outbound side.
+/// Current counts of various HTLCs, useful for calculating current balances available exactly.
struct HTLCStats {
- pending_htlcs: u32,
- pending_htlcs_value_msat: u64,
+ pending_inbound_htlcs: usize,
+ pending_outbound_htlcs: usize,
+ pending_inbound_htlcs_value_msat: u64,
+ pending_outbound_htlcs_value_msat: u64,
on_counterparty_tx_dust_exposure_msat: u64,
on_holder_tx_dust_exposure_msat: u64,
- holding_cell_msat: u64,
- on_holder_tx_holding_cell_htlcs_count: u32, // dust HTLCs *non*-included
+ outbound_holding_cell_msat: u64,
+ on_holder_tx_outbound_holding_cell_htlcs_count: u32, // dust HTLCs *non*-included
}
/// An enum gathering stats on commitment transaction, either local or remote.
self.counterparty_forwarding_info.clone()
}
- /// Returns a HTLCStats about inbound pending htlcs
- fn get_inbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
+ /// Returns a HTLCStats about pending htlcs
+ fn get_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
let context = self;
- let mut stats = HTLCStats {
- pending_htlcs: context.pending_inbound_htlcs.len() as u32,
- pending_htlcs_value_msat: 0,
- on_counterparty_tx_dust_exposure_msat: 0,
- on_holder_tx_dust_exposure_msat: 0,
- holding_cell_msat: 0,
- on_holder_tx_holding_cell_htlcs_count: 0,
- };
+ let uses_0_htlc_fee_anchors = self.get_channel_type().supports_anchors_zero_fee_htlc_tx();
- let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+ let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if uses_0_htlc_fee_anchors {
(0, 0)
} else {
let dust_buffer_feerate = context.get_dust_buffer_feerate(outbound_feerate_update) as u64;
(dust_buffer_feerate * htlc_timeout_tx_weight(context.get_channel_type()) / 1000,
dust_buffer_feerate * htlc_success_tx_weight(context.get_channel_type()) / 1000)
};
+
+ let mut on_holder_tx_dust_exposure_msat = 0;
+ let mut on_counterparty_tx_dust_exposure_msat = 0;
+
+ let mut pending_inbound_htlcs_value_msat = 0;
+ {
let counterparty_dust_limit_timeout_sat = htlc_timeout_dust_limit + context.counterparty_dust_limit_satoshis;
let holder_dust_limit_success_sat = htlc_success_dust_limit + context.holder_dust_limit_satoshis;
for ref htlc in context.pending_inbound_htlcs.iter() {
- stats.pending_htlcs_value_msat += htlc.amount_msat;
+ pending_inbound_htlcs_value_msat += htlc.amount_msat;
if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
- stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
+ on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
}
if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
- stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
+ on_holder_tx_dust_exposure_msat += htlc.amount_msat;
}
}
- stats
- }
-
- /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
- fn get_outbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
- let context = self;
- let mut stats = HTLCStats {
- pending_htlcs: context.pending_outbound_htlcs.len() as u32,
- pending_htlcs_value_msat: 0,
- on_counterparty_tx_dust_exposure_msat: 0,
- on_holder_tx_dust_exposure_msat: 0,
- holding_cell_msat: 0,
- on_holder_tx_holding_cell_htlcs_count: 0,
- };
+ }
- let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
- (0, 0)
- } else {
- let dust_buffer_feerate = context.get_dust_buffer_feerate(outbound_feerate_update) as u64;
- (dust_buffer_feerate * htlc_timeout_tx_weight(context.get_channel_type()) / 1000,
- dust_buffer_feerate * htlc_success_tx_weight(context.get_channel_type()) / 1000)
- };
+ let mut pending_outbound_htlcs_value_msat = 0;
+ let mut outbound_holding_cell_msat = 0;
+ let mut on_holder_tx_outbound_holding_cell_htlcs_count = 0;
+ let mut pending_outbound_htlcs = self.pending_outbound_htlcs.len();
+ {
let counterparty_dust_limit_success_sat = htlc_success_dust_limit + context.counterparty_dust_limit_satoshis;
let holder_dust_limit_timeout_sat = htlc_timeout_dust_limit + context.holder_dust_limit_satoshis;
for ref htlc in context.pending_outbound_htlcs.iter() {
- stats.pending_htlcs_value_msat += htlc.amount_msat;
+ pending_outbound_htlcs_value_msat += htlc.amount_msat;
if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
- stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
+ on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
}
if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
- stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
+ on_holder_tx_dust_exposure_msat += htlc.amount_msat;
}
}
for update in context.holding_cell_htlc_updates.iter() {
if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
- stats.pending_htlcs += 1;
- stats.pending_htlcs_value_msat += amount_msat;
- stats.holding_cell_msat += amount_msat;
+ pending_outbound_htlcs += 1;
+ pending_outbound_htlcs_value_msat += amount_msat;
+ outbound_holding_cell_msat += amount_msat;
if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
- stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
+ on_counterparty_tx_dust_exposure_msat += amount_msat;
}
if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
- stats.on_holder_tx_dust_exposure_msat += amount_msat;
+ on_holder_tx_dust_exposure_msat += amount_msat;
} else {
- stats.on_holder_tx_holding_cell_htlcs_count += 1;
+ on_holder_tx_outbound_holding_cell_htlcs_count += 1;
}
}
}
- stats
+ }
+
+ HTLCStats {
+ pending_inbound_htlcs: self.pending_inbound_htlcs.len(),
+ pending_outbound_htlcs,
+ pending_inbound_htlcs_value_msat,
+ pending_outbound_htlcs_value_msat,
+ on_counterparty_tx_dust_exposure_msat,
+ on_holder_tx_dust_exposure_msat,
+ outbound_holding_cell_msat,
+ on_holder_tx_outbound_holding_cell_htlcs_count,
+ }
}
/// Returns information on all pending inbound HTLCs.
{
let context = &self;
// Note that we have to handle overflow due to the above case.
- let inbound_stats = context.get_inbound_pending_htlc_stats(None);
- let outbound_stats = context.get_outbound_pending_htlc_stats(None);
+ let htlc_stats = context.get_pending_htlc_stats(None);
let mut balance_msat = context.value_to_self_msat;
for ref htlc in context.pending_inbound_htlcs.iter() {
balance_msat += htlc.amount_msat;
}
}
- balance_msat -= outbound_stats.pending_htlcs_value_msat;
+ balance_msat -= htlc_stats.pending_outbound_htlcs_value_msat;
let outbound_capacity_msat = context.value_to_self_msat
- .saturating_sub(outbound_stats.pending_htlcs_value_msat)
+ .saturating_sub(htlc_stats.pending_outbound_htlcs_value_msat)
.saturating_sub(
context.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) * 1000);
let holder_selected_chan_reserve_msat = context.holder_selected_channel_reserve_satoshis * 1000;
let remote_balance_msat = (context.channel_value_satoshis * 1000 - context.value_to_self_msat)
- .saturating_sub(inbound_stats.pending_htlcs_value_msat);
+ .saturating_sub(htlc_stats.pending_inbound_htlcs_value_msat);
if remote_balance_msat < max_reserved_commit_tx_fee_msat + holder_selected_chan_reserve_msat + anchor_outputs_value_msat {
// If another HTLC's fee would reduce the remote's balance below the reserve limit
(context.counterparty_dust_limit_satoshis + dust_buffer_feerate * htlc_success_tx_weight(context.get_channel_type()) / 1000,
context.holder_dust_limit_satoshis + dust_buffer_feerate * htlc_timeout_tx_weight(context.get_channel_type()) / 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 > max_dust_htlc_exposure_msat.try_into().unwrap_or(i64::max_value()) {
+ if htlc_stats.on_counterparty_tx_dust_exposure_msat as i64 + htlc_success_dust_limit as i64 * 1000 - 1 > max_dust_htlc_exposure_msat.try_into().unwrap_or(i64::max_value()) {
remaining_msat_below_dust_exposure_limit =
- Some(max_dust_htlc_exposure_msat.saturating_sub(on_counterparty_dust_htlc_exposure_msat));
+ Some(max_dust_htlc_exposure_msat.saturating_sub(htlc_stats.on_counterparty_tx_dust_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 > max_dust_htlc_exposure_msat.try_into().unwrap_or(i64::max_value()) {
+ if htlc_stats.on_holder_tx_dust_exposure_msat as i64 + htlc_timeout_dust_limit as i64 * 1000 - 1 > max_dust_htlc_exposure_msat.try_into().unwrap_or(i64::max_value()) {
remaining_msat_below_dust_exposure_limit = Some(cmp::min(
remaining_msat_below_dust_exposure_limit.unwrap_or(u64::max_value()),
- max_dust_htlc_exposure_msat.saturating_sub(on_holder_dust_htlc_exposure_msat)));
+ max_dust_htlc_exposure_msat.saturating_sub(htlc_stats.on_holder_tx_dust_exposure_msat)));
dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_timeout_dust_limit * 1000);
}
}
available_capacity_msat = cmp::min(available_capacity_msat,
- context.counterparty_max_htlc_value_in_flight_msat - outbound_stats.pending_htlcs_value_msat);
+ context.counterparty_max_htlc_value_in_flight_msat - htlc_stats.pending_outbound_htlcs_value_msat);
- if outbound_stats.pending_htlcs + 1 > context.counterparty_max_accepted_htlcs as u32 {
+ if htlc_stats.pending_outbound_htlcs + 1 > context.counterparty_max_accepted_htlcs as usize {
available_capacity_msat = 0;
}
AvailableBalances {
inbound_capacity_msat: cmp::max(context.channel_value_satoshis as i64 * 1000
- context.value_to_self_msat as i64
- - context.get_inbound_pending_htlc_stats(None).pending_htlcs_value_msat as i64
+ - htlc_stats.pending_inbound_htlcs_value_msat as i64
- context.holder_selected_channel_reserve_satoshis as i64 * 1000,
0) as u64,
outbound_capacity_msat,
return Err(ChannelError::Close(format!("Remote side tried to send less than our minimum HTLC value. Lower limit: ({}). Actual: ({})", self.context.holder_htlc_minimum_msat, msg.amount_msat)));
}
- let inbound_stats = self.context.get_inbound_pending_htlc_stats(None);
- if inbound_stats.pending_htlcs + 1 > self.context.holder_max_accepted_htlcs as u32 {
+ let htlc_stats = self.context.get_pending_htlc_stats(None);
+ if htlc_stats.pending_inbound_htlcs + 1 > self.context.holder_max_accepted_htlcs as usize {
return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", self.context.holder_max_accepted_htlcs)));
}
- if inbound_stats.pending_htlcs_value_msat + msg.amount_msat > self.context.holder_max_htlc_value_in_flight_msat {
+ if htlc_stats.pending_inbound_htlcs_value_msat + msg.amount_msat > self.context.holder_max_htlc_value_in_flight_msat {
return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", self.context.holder_max_htlc_value_in_flight_msat)));
}
}
let pending_value_to_self_msat =
- self.context.value_to_self_msat + inbound_stats.pending_htlcs_value_msat - removed_outbound_total_msat;
+ self.context.value_to_self_msat + htlc_stats.pending_inbound_htlcs_value_msat - removed_outbound_total_msat;
let pending_remote_value_msat =
self.context.channel_value_satoshis * 1000 - pending_value_to_self_msat;
if pending_remote_value_msat < msg.amount_msat {
}
// Before proposing a feerate update, check that we can actually afford the new fee.
- let inbound_stats = self.context.get_inbound_pending_htlc_stats(Some(feerate_per_kw));
- let outbound_stats = self.context.get_outbound_pending_htlc_stats(Some(feerate_per_kw));
+ let htlc_stats = self.context.get_pending_htlc_stats(Some(feerate_per_kw));
let keys = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
let commitment_stats = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, true, logger);
- let buffer_fee_msat = commit_tx_fee_sat(feerate_per_kw, commitment_stats.num_nondust_htlcs + outbound_stats.on_holder_tx_holding_cell_htlcs_count as usize + CONCURRENT_INBOUND_HTLC_FEE_BUFFER as usize, self.context.get_channel_type()) * 1000;
- let holder_balance_msat = commitment_stats.local_balance_msat - outbound_stats.holding_cell_msat;
+ let buffer_fee_msat = commit_tx_fee_sat(feerate_per_kw, commitment_stats.num_nondust_htlcs + htlc_stats.on_holder_tx_outbound_holding_cell_htlcs_count as usize + CONCURRENT_INBOUND_HTLC_FEE_BUFFER as usize, self.context.get_channel_type()) * 1000;
+ let holder_balance_msat = commitment_stats.local_balance_msat - htlc_stats.outbound_holding_cell_msat;
if holder_balance_msat < buffer_fee_msat + self.context.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 {
//TODO: auto-close after a number of failures?
log_debug!(logger, "Cannot afford to send new feerate at {}", feerate_per_kw);
}
// Note, we evaluate pending htlc "preemptive" trimmed-to-dust threshold at the proposed `feerate_per_kw`.
- let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
- let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
let max_dust_htlc_exposure_msat = self.context.get_max_dust_htlc_exposure_msat(fee_estimator);
- if holder_tx_dust_exposure > max_dust_htlc_exposure_msat {
+ if htlc_stats.on_holder_tx_dust_exposure_msat > max_dust_htlc_exposure_msat {
log_debug!(logger, "Cannot afford to send new feerate at {} without infringing max dust htlc exposure", feerate_per_kw);
return None;
}
- if counterparty_tx_dust_exposure > max_dust_htlc_exposure_msat {
+ if htlc_stats.on_counterparty_tx_dust_exposure_msat > max_dust_htlc_exposure_msat {
log_debug!(logger, "Cannot afford to send new feerate at {} without infringing max dust htlc exposure", feerate_per_kw);
return None;
}
self.context.update_time_counter += 1;
// Check that we won't be pushed over our dust exposure limit by the feerate increase.
if !self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
- let inbound_stats = self.context.get_inbound_pending_htlc_stats(None);
- let outbound_stats = self.context.get_outbound_pending_htlc_stats(None);
- let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
- let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
+ let htlc_stats = self.context.get_pending_htlc_stats(None);
let max_dust_htlc_exposure_msat = self.context.get_max_dust_htlc_exposure_msat(fee_estimator);
- if holder_tx_dust_exposure > max_dust_htlc_exposure_msat {
+ if htlc_stats.on_holder_tx_dust_exposure_msat > max_dust_htlc_exposure_msat {
return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our own transactions (totaling {} msat)",
- msg.feerate_per_kw, holder_tx_dust_exposure)));
+ msg.feerate_per_kw, htlc_stats.on_holder_tx_dust_exposure_msat)));
}
- if counterparty_tx_dust_exposure > max_dust_htlc_exposure_msat {
+ if htlc_stats.on_counterparty_tx_dust_exposure_msat > max_dust_htlc_exposure_msat {
return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our counterparty's transactions (totaling {} msat)",
- msg.feerate_per_kw, counterparty_tx_dust_exposure)));
+ msg.feerate_per_kw, htlc_stats.on_counterparty_tx_dust_exposure_msat)));
}
}
Ok(())
return Err(("Shutdown was already sent", 0x4000|8))
}
- let inbound_stats = self.context.get_inbound_pending_htlc_stats(None);
- let outbound_stats = self.context.get_outbound_pending_htlc_stats(None);
+ let htlc_stats = self.context.get_pending_htlc_stats(None);
let max_dust_htlc_exposure_msat = self.context.get_max_dust_htlc_exposure_msat(fee_estimator);
let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if self.context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
(0, 0)
};
let exposure_dust_limit_timeout_sats = htlc_timeout_dust_limit + self.context.counterparty_dust_limit_satoshis;
if msg.amount_msat / 1000 < exposure_dust_limit_timeout_sats {
- let on_counterparty_tx_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + msg.amount_msat;
+ let on_counterparty_tx_dust_htlc_exposure_msat = htlc_stats.on_counterparty_tx_dust_exposure_msat + msg.amount_msat;
if on_counterparty_tx_dust_htlc_exposure_msat > max_dust_htlc_exposure_msat {
log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
on_counterparty_tx_dust_htlc_exposure_msat, max_dust_htlc_exposure_msat);
let exposure_dust_limit_success_sats = htlc_success_dust_limit + self.context.holder_dust_limit_satoshis;
if msg.amount_msat / 1000 < exposure_dust_limit_success_sats {
- let on_holder_tx_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + msg.amount_msat;
+ let on_holder_tx_dust_htlc_exposure_msat = htlc_stats.on_holder_tx_dust_exposure_msat + msg.amount_msat;
if on_holder_tx_dust_htlc_exposure_msat > max_dust_htlc_exposure_msat {
log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
on_holder_tx_dust_htlc_exposure_msat, max_dust_htlc_exposure_msat);
}
let pending_value_to_self_msat =
- self.context.value_to_self_msat + inbound_stats.pending_htlcs_value_msat - removed_outbound_total_msat;
+ self.context.value_to_self_msat + htlc_stats.pending_inbound_htlcs_value_msat - removed_outbound_total_msat;
let pending_remote_value_msat =
self.context.channel_value_satoshis * 1000 - pending_value_to_self_msat;