}
}
+ /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
+ /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
+ /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
+ /// before we fail backwards.
+ ///
+ /// If we do fail twice, we debug_assert!(false) and return Ok(()). Thus, will always return
+ /// Ok(()) if debug assertions are turned on or preconditions are met.
+ pub fn queue_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L)
+ -> Result<(), ChannelError> where L::Target: Logger {
+ self.fail_htlc(htlc_id_arg, err_packet, true, logger)
+ .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
+ }
+
/// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
/// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
/// however, fail more than once as we wait for an upstream failure to be irrevocably committed
/// before we fail backwards.
/// If we do fail twice, we debug_assert!(false) and return Ok(None). Thus, will always return
/// Ok(_) if debug assertions are turned on or preconditions are met.
- pub fn get_update_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
+ fn fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, mut force_holding_cell: bool, logger: &L)
+ -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
panic!("Was asked to fail an HTLC when channel was not in an operational state");
}
return Ok(None);
}
- // Now update local state:
if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+ debug_assert!(force_holding_cell, "We don't expect to need to use the holding cell if we weren't trying to");
+ force_holding_cell = true;
+ }
+
+ // Now update local state:
+ if force_holding_cell {
for pending_update in self.holding_cell_htlc_updates.iter() {
match pending_update {
&HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
} else { Ok((None, Vec::new())) }
}
- /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
- /// fulfilling or failing the last pending HTLC)
+ /// 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) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
assert_eq!(self.channel_state & ChannelState::MonitorUpdateInProgress as u32, 0);
if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
// 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(), logger) {
+ 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 {
monitor_update.updates.append(&mut additional_monitor_update.updates);
},
&HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
- match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
+ 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
- // `get_update_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.
+ // `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) => {
// Send stuff to our remote peers:
+ /// Queues up an outbound HTLC to send by placing it in the holding cell. You should call
+ /// [`Self::maybe_free_holding_cell_htlcs`] in order to actually generate and send the
+ /// commitment update.
+ ///
+ /// `Err`s will only be [`ChannelError::Ignore`].
+ pub fn queue_add_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource,
+ onion_routing_packet: msgs::OnionPacket, logger: &L)
+ -> Result<(), ChannelError> where L::Target: Logger {
+ self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, true, logger)
+ .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
+ }
+
/// Adds a pending outbound HTLC to this channel, note that you probably want
/// send_htlc_and_commit instead cause you'll want both messages at once.
///
/// we may not yet have sent the previous commitment update messages and will need to
/// regenerate them.
///
- /// You MUST call send_commitment prior to calling any other methods on this Channel!
+ /// You MUST call send_commitment prior to calling any other methods on this Channel if
+ /// `force_holding_cell` is false.
///
/// If an Err is returned, it's a ChannelError::Ignore!
- pub fn send_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> where L::Target: Logger {
+ fn send_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource,
+ onion_routing_packet: msgs::OnionPacket, mut force_holding_cell: bool, logger: &L)
+ -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> where L::Target: Logger {
if (self.channel_state & (ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelReady as u32) {
return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
}
return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
}
- // Now update local state:
if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+ force_holding_cell = true;
+ }
+
+ // Now update local state:
+ if force_holding_cell {
self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
amount_msat,
payment_hash,
/// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
/// more info.
pub fn send_htlc_and_commit<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
- match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, logger)? {
+ match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, false, logger)? {
Some(update_add_htlc) => {
let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
Ok(Some((update_add_htlc, commitment_signed, monitor_update)))