}
}
+ /// 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)))
let mut new_events = Vec::new();
let mut failed_forwards = Vec::new();
let mut phantom_receives: Vec<(u64, OutPoint, u128, Vec<(PendingHTLCInfo, u64)>)> = Vec::new();
- let mut handle_errors = Vec::new();
{
let mut forward_htlcs = HashMap::new();
mem::swap(&mut forward_htlcs, &mut self.forward_htlcs.lock().unwrap());
continue;
},
hash_map::Entry::Occupied(mut chan) => {
- let mut add_htlc_msgs = Vec::new();
- let mut fail_htlc_msgs = Vec::new();
for forward_info in pending_forwards.drain(..) {
match forward_info {
HTLCForwardInfo::AddHTLC(PendingAddHTLCInfo {
// Phantom payments are only PendingHTLCRouting::Receive.
phantom_shared_secret: None,
});
- match chan.get_mut().send_htlc(outgoing_amt_msat, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet, &self.logger) {
- Err(e) => {
- if let ChannelError::Ignore(msg) = e {
- log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
- } else {
- panic!("Stated return value requirements in send_htlc() were not met");
- }
- let (failure_code, data) = self.get_htlc_temp_fail_err_and_data(0x1000|7, short_chan_id, chan.get());
- failed_forwards.push((htlc_source, payment_hash,
- HTLCFailReason::reason(failure_code, data),
- HTLCDestination::NextHopChannel { node_id: Some(chan.get().get_counterparty_node_id()), channel_id: forward_chan_id }
- ));
- continue;
- },
- Ok(update_add) => {
- match update_add {
- Some(msg) => { add_htlc_msgs.push(msg); },
- None => {
- // Nothing to do here...we're waiting on a remote
- // revoke_and_ack before we can add anymore HTLCs. The Channel
- // will automatically handle building the update_add_htlc and
- // commitment_signed messages when we can.
- // TODO: Do some kind of timer to set the channel as !is_live()
- // as we don't really want others relying on us relaying through
- // this channel currently :/.
- }
- }
+ if let Err(e) = chan.get_mut().queue_add_htlc(outgoing_amt_msat,
+ payment_hash, outgoing_cltv_value, htlc_source.clone(),
+ onion_packet, &self.logger)
+ {
+ if let ChannelError::Ignore(msg) = e {
+ log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
+ } else {
+ panic!("Stated return value requirements in send_htlc() were not met");
}
+ let (failure_code, data) = self.get_htlc_temp_fail_err_and_data(0x1000|7, short_chan_id, chan.get());
+ failed_forwards.push((htlc_source, payment_hash,
+ HTLCFailReason::reason(failure_code, data),
+ HTLCDestination::NextHopChannel { node_id: Some(chan.get().get_counterparty_node_id()), channel_id: forward_chan_id }
+ ));
+ continue;
}
},
HTLCForwardInfo::AddHTLC { .. } => {
},
HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
log_trace!(self.logger, "Failing HTLC back to channel with short id {} (backward HTLC ID {}) after delay", short_chan_id, htlc_id);
- match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet, &self.logger) {
- Err(e) => {
- if let ChannelError::Ignore(msg) = e {
- log_trace!(self.logger, "Failed to fail HTLC with ID {} backwards to short_id {}: {}", htlc_id, short_chan_id, msg);
- } else {
- panic!("Stated return value requirements in get_update_fail_htlc() were not met");
- }
- // fail-backs are best-effort, we probably already have one
- // pending, and if not that's OK, if not, the channel is on
- // the chain and sending the HTLC-Timeout is their problem.
- continue;
- },
- Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
- Ok(None) => {
- // Nothing to do here...we're waiting on a remote
- // revoke_and_ack before we can update the commitment
- // transaction. The Channel will automatically handle
- // building the update_fail_htlc and commitment_signed
- // messages when we can.
- // We don't need any kind of timer here as they should fail
- // the channel onto the chain if they can't get our
- // update_fail_htlc in time, it's not our problem.
+ if let Err(e) = chan.get_mut().queue_fail_htlc(
+ htlc_id, err_packet, &self.logger
+ ) {
+ if let ChannelError::Ignore(msg) = e {
+ log_trace!(self.logger, "Failed to fail HTLC with ID {} backwards to short_id {}: {}", htlc_id, short_chan_id, msg);
+ } else {
+ panic!("Stated return value requirements in queue_fail_htlc() were not met");
}
+ // fail-backs are best-effort, we probably already have one
+ // pending, and if not that's OK, if not, the channel is on
+ // the chain and sending the HTLC-Timeout is their problem.
+ continue;
}
},
}
}
-
- if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
- let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment(&self.logger) {
- Ok(res) => res,
- Err(e) => {
- // We surely failed send_commitment due to bad keys, in that case
- // close channel and then send error message to peer.
- let counterparty_node_id = chan.get().get_counterparty_node_id();
- let err: Result<(), _> = match e {
- ChannelError::Ignore(_) | ChannelError::Warn(_) => {
- panic!("Stated return value requirements in send_commitment() were not met");
- }
- ChannelError::Close(msg) => {
- log_trace!(self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
- let mut channel = remove_channel!(self, chan);
- // ChannelClosed event is generated by handle_error for us.
- Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel.channel_id(), channel.get_user_id(), channel.force_shutdown(true), self.get_channel_update_for_broadcast(&channel).ok()))
- },
- };
- handle_errors.push((counterparty_node_id, err));
- continue;
- }
- };
- match self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
- ChannelMonitorUpdateStatus::Completed => {},
- e => {
- handle_errors.push((chan.get().get_counterparty_node_id(), handle_monitor_update_res!(self, e, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
- continue;
- }
- }
- log_debug!(self.logger, "Forwarding HTLCs resulted in a commitment update with {} HTLCs added and {} HTLCs failed for channel {}",
- add_htlc_msgs.len(), fail_htlc_msgs.len(), log_bytes!(chan.get().channel_id()));
- channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
- node_id: chan.get().get_counterparty_node_id(),
- updates: msgs::CommitmentUpdate {
- update_add_htlcs: add_htlc_msgs,
- update_fulfill_htlcs: Vec::new(),
- update_fail_htlcs: fail_htlc_msgs,
- update_fail_malformed_htlcs: Vec::new(),
- update_fee: None,
- commitment_signed: commitment_msg,
- },
- });
- }
}
}
} else {
}
self.forward_htlcs(&mut phantom_receives);
- for (counterparty_node_id, err) in handle_errors.drain(..) {
- let _ = handle_error!(self, err, counterparty_node_id);
- }
+ // Freeing the holding cell here is relatively redundant - in practice we'll do it when we
+ // next get a `get_and_clear_pending_msg_events` call, but some tests rely on it, and it's
+ // nice to do the work now if we can rather than while we're trying to get messages in the
+ // network stack.
+ self.check_free_holding_cells();
if new_events.is_empty() { return }
let mut events = self.pending_events.lock().unwrap();
/// Check the holding cell in each channel and free any pending HTLCs in them if possible.
/// Returns whether there were any updates such as if pending HTLCs were freed or a monitor
/// update was applied.
- ///
- /// This should only apply to HTLCs which were added to the holding cell because we were
- /// waiting on a monitor update to finish. In that case, we don't want to free the holding cell
- /// directly in `channel_monitor_updated` as it may introduce deadlocks calling back into user
- /// code to inform them of a channel monitor update.
fn check_free_holding_cells(&self) -> bool {
let mut has_monitor_update = false;
let mut failed_htlcs = Vec::new();
projects / rust-lightning / commitdiff