+ let need_commitment_signed = if need_commitment && (self.context.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 mut additional_update = self.build_commitment_no_status_check(logger);
+ // build_commitment_no_status_check may bump latest_monitor_id but we want them to be
+ // strictly increasing by one, so decrement it here.
+ self.context.latest_monitor_update_id = monitor_update.update_id;
+ monitor_update.updates.append(&mut additional_update.updates);
+ true
+ } else { false };
+
+ log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updating HTLC state and responding with{} a revoke_and_ack.",
+ log_bytes!(self.context.channel_id()), if need_commitment_signed { " our own commitment_signed and" } else { "" });
+ self.monitor_updating_paused(true, need_commitment_signed, false, Vec::new(), Vec::new(), Vec::new());
+ return Ok(self.push_ret_blockable_mon_update(monitor_update));
+ }
+
+ /// Public version of the below, checking relevant preconditions first.
+ /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
+ /// returns `(None, Vec::new())`.
+ pub fn maybe_free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> (Option<&ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>) where L::Target: Logger {
+ if self.context.channel_state >= ChannelState::ChannelReady as u32 &&
+ (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) == 0 {
+ self.free_holding_cell_htlcs(logger)
+ } else { (None, Vec::new()) }
+ }
+
+ /// Frees any pending commitment updates in the holding cell, generating the relevant messages
+ /// for our counterparty.
+ fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> (Option<&ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>) where L::Target: Logger {
+ assert_eq!(self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32, 0);
+ if self.context.holding_cell_htlc_updates.len() != 0 || self.context.holding_cell_update_fee.is_some() {
+ log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.context.holding_cell_htlc_updates.len(),
+ if self.context.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.context.channel_id()));
+
+ let mut monitor_update = ChannelMonitorUpdate {
+ update_id: self.context.latest_monitor_update_id + 1, // We don't increment this yet!
+ updates: Vec::new(),
+ };
+
+ let mut htlc_updates = Vec::new();
+ mem::swap(&mut htlc_updates, &mut self.context.holding_cell_htlc_updates);
+ let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
+ let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
+ let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
+ let mut htlcs_to_fail = Vec::new();
+ for htlc_update in htlc_updates.drain(..) {
+ // Note that this *can* fail, though it should be due to rather-rare conditions on
+ // fee races with adding too many outputs which push our total payments just over
+ // the limit. In case it's less rare than I anticipate, we may want to revisit
+ // handling this case better and maybe fulfilling some of the HTLCs while attempting
+ // to rebalance channels.
+ match &htlc_update {
+ &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
+ match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone(), false, logger) {
+ Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
+ Err(e) => {
+ match e {
+ ChannelError::Ignore(ref msg) => {
+ log_info!(logger, "Failed to send HTLC with payment_hash {} due to {} in channel {}",
+ log_bytes!(payment_hash.0), msg, log_bytes!(self.context.channel_id()));
+ // If we fail to send here, then this HTLC should
+ // be failed backwards. Failing to send here
+ // indicates that this HTLC may keep being put back
+ // into the holding cell without ever being
+ // successfully forwarded/failed/fulfilled, causing
+ // our counterparty to eventually close on us.
+ htlcs_to_fail.push((source.clone(), *payment_hash));
+ },
+ _ => {
+ panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
+ },
+ }
+ }
+ }
+ },
+ &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
+ // If an HTLC claim was previously added to the holding cell (via
+ // `get_update_fulfill_htlc`, then generating the claim message itself must
+ // not fail - any in between attempts to claim the HTLC will have resulted
+ // in it hitting the holding cell again and we cannot change the state of a
+ // holding cell HTLC from fulfill to anything else.
+ let (update_fulfill_msg_option, mut additional_monitor_update) =
+ if let UpdateFulfillFetch::NewClaim { msg, monitor_update, .. } = self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
+ (msg, monitor_update)
+ } else { unreachable!() };
+ update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
+ monitor_update.updates.append(&mut additional_monitor_update.updates);
+ },
+ &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
+ match self.fail_htlc(htlc_id, err_packet.clone(), false, logger) {
+ Ok(update_fail_msg_option) => {
+ // If an HTLC failure was previously added to the holding cell (via
+ // `queue_fail_htlc`) then generating the fail message itself must
+ // not fail - we should never end up in a state where we double-fail
+ // an HTLC or fail-then-claim an HTLC as it indicates we didn't wait
+ // for a full revocation before failing.
+ update_fail_htlcs.push(update_fail_msg_option.unwrap())
+ },
+ Err(e) => {
+ if let ChannelError::Ignore(_) = e {}
+ else {
+ panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
+ }
+ }
+ }
+ },