pub cltv_expiry_delta: u16,
}
+/// A return value enum for get_update_fulfill_htlc. See UpdateFulfillCommitFetch variants for
+/// description
+enum UpdateFulfillFetch {
+ NewClaim {
+ monitor_update: ChannelMonitorUpdate,
+ msg: Option<msgs::UpdateFulfillHTLC>,
+ },
+ DuplicateClaim {},
+}
+
+/// The return type of get_update_fulfill_htlc_and_commit.
+pub enum UpdateFulfillCommitFetch {
+ /// Indicates the HTLC fulfill is new, and either generated an update_fulfill message, placed
+ /// it in the holding cell, or re-generated the update_fulfill message after the same claim was
+ /// previously placed in the holding cell (and has since been removed).
+ NewClaim {
+ /// The ChannelMonitorUpdate which places the new payment preimage in the channel monitor
+ monitor_update: ChannelMonitorUpdate,
+ /// The update_fulfill message and commitment_signed message (if the claim was not placed
+ /// in the holding cell).
+ msgs: Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>,
+ },
+ /// Indicates the HTLC fulfill is duplicative and already existed either in the holding cell
+ /// or has been forgotten (presumably previously claimed).
+ DuplicateClaim {},
+}
+
// TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
// has been completed, and then turn into a Channel to get compiler-time enforcement of things like
// calling channel_id() before we're set up or things like get_outbound_funding_signed on an
make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
}
- /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
- /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
- /// return Ok(_) if debug assertions are turned on or preconditions are met.
- ///
- /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
- /// but then have a reorg which settles on an HTLC-failure on chain.
- fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitorUpdate>), ChannelError> where L::Target: Logger {
+ fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
// Either ChannelFunded got set (which means it won't be unset) or there is no way any
// caller thought we could have something claimed (cause we wouldn't have accepted in an
// incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
log_warn!(logger, "Have preimage and want to fulfill HTLC with payment hash {} we already failed against channel {}", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id()));
debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
}
- return Ok((None, None));
+ return UpdateFulfillFetch::DuplicateClaim {};
},
_ => {
debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
// If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
// this is simply a duplicate claim, not previously failed and we lost funds.
debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
- return Ok((None, None));
+ return UpdateFulfillFetch::DuplicateClaim {};
}
// Now update local state:
self.latest_monitor_update_id -= 1;
#[cfg(any(test, feature = "fuzztarget"))]
debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
- return Ok((None, None));
+ return UpdateFulfillFetch::DuplicateClaim {};
}
},
&HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
// TODO: We may actually be able to switch to a fulfill here, though its
// rare enough it may not be worth the complexity burden.
debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
- return Ok((None, Some(monitor_update)));
+ return UpdateFulfillFetch::NewClaim { monitor_update, msg: None };
}
},
_ => {}
});
#[cfg(any(test, feature = "fuzztarget"))]
self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
- return Ok((None, Some(monitor_update)));
+ return UpdateFulfillFetch::NewClaim { monitor_update, msg: None };
}
#[cfg(any(test, feature = "fuzztarget"))]
self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
if let InboundHTLCState::Committed = htlc.state {
} else {
debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
- return Ok((None, Some(monitor_update)));
+ return UpdateFulfillFetch::NewClaim { monitor_update, msg: None };
}
log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
}
- Ok((Some(msgs::UpdateFulfillHTLC {
- channel_id: self.channel_id(),
- htlc_id: htlc_id_arg,
- payment_preimage: payment_preimage_arg,
- }), Some(monitor_update)))
+ UpdateFulfillFetch::NewClaim {
+ monitor_update,
+ msg: Some(msgs::UpdateFulfillHTLC {
+ channel_id: self.channel_id(),
+ htlc_id: htlc_id_arg,
+ payment_preimage: payment_preimage_arg,
+ }),
+ }
}
- pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitorUpdate>), ChannelError> where L::Target: Logger {
- match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger)? {
- (Some(update_fulfill_htlc), Some(mut monitor_update)) => {
+ pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<UpdateFulfillCommitFetch, ChannelError> where L::Target: Logger {
+ match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
+ UpdateFulfillFetch::NewClaim { mut monitor_update, msg: Some(update_fulfill_htlc) } => {
let (commitment, mut additional_update) = self.send_commitment_no_status_check(logger)?;
// send_commitment_no_status_check may bump latest_monitor_id but we want them to be
// strictly increasing by one, so decrement it here.
self.latest_monitor_update_id = monitor_update.update_id;
monitor_update.updates.append(&mut additional_update.updates);
- Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
- },
- (Some(update_fulfill_htlc), None) => {
- let (commitment, monitor_update) = self.send_commitment_no_status_check(logger)?;
- Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
+ Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, msgs: Some((update_fulfill_htlc, commitment)) })
},
- (None, Some(monitor_update)) => Ok((None, Some(monitor_update))),
- (None, None) => Ok((None, None))
+ UpdateFulfillFetch::NewClaim { monitor_update, msg: None } => Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, msgs: None }),
+ UpdateFulfillFetch::DuplicateClaim {} => Ok(UpdateFulfillCommitFetch::DuplicateClaim {}),
}
}
- /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
- /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
- /// return Ok(_) if debug assertions are turned on or preconditions are met.
- ///
- /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
- /// but then have a reorg which settles on an HTLC-failure on chain.
+ /// 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 {
if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
panic!("Was asked to fail an HTLC when channel was not in an operational state");
}
},
&HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
- match self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
- Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => {
- update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
- if let Some(mut additional_monitor_update) = additional_monitor_update_opt {
- monitor_update.updates.append(&mut additional_monitor_update.updates);
- }
- },
- Err(e) => {
- if let ChannelError::Ignore(_) = e {}
- else {
- panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC");
- }
- }
- }
+ // 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.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
// construct one themselves.
use ln::{PaymentHash, PaymentPreimage, PaymentSecret};
pub use ln::channel::CounterpartyForwardingInfo;
-use ln::channel::{Channel, ChannelError, ChannelUpdateStatus};
+use ln::channel::{Channel, ChannelError, ChannelUpdateStatus, UpdateFulfillCommitFetch};
use ln::features::{InitFeatures, NodeFeatures};
use routing::router::{Route, RouteHop};
use ln::msgs;
if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
- Ok((msgs, monitor_option)) => {
- if let Some(monitor_update) = monitor_option {
+ Ok(msgs_monitor_option) => {
+ if let UpdateFulfillCommitFetch::NewClaim { msgs, monitor_update } = msgs_monitor_option {
if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
if was_frozen_for_monitor {
assert!(msgs.is_none());
return Err(Some((chan.get().get_counterparty_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err())));
}
}
- }
- if let Some((msg, commitment_signed)) = msgs {
- log_debug!(self.logger, "Claiming funds for HTLC with preimage {} resulted in a commitment_signed for channel {}",
- log_bytes!(payment_preimage.0), 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: Vec::new(),
- update_fulfill_htlcs: vec![msg],
- update_fail_htlcs: Vec::new(),
- update_fail_malformed_htlcs: Vec::new(),
- update_fee: None,
- commitment_signed,
- }
- });
+ if let Some((msg, commitment_signed)) = msgs {
+ log_debug!(self.logger, "Claiming funds for HTLC with preimage {} resulted in a commitment_signed for channel {}",
+ log_bytes!(payment_preimage.0), 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: Vec::new(),
+ update_fulfill_htlcs: vec![msg],
+ update_fail_htlcs: Vec::new(),
+ update_fail_malformed_htlcs: Vec::new(),
+ update_fee: None,
+ commitment_signed,
+ }
+ });
+ }
}
return Ok(())
},
projects / rust-lightning / commitdiff