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
///
/// See-also <https://github.com/lightningnetwork/lnd/issues/4006>
pub workaround_lnd_bug_4006: Option<msgs::FundingLocked>,
+
+ #[cfg(any(test, feature = "fuzztarget"))]
+ // When we receive an HTLC fulfill on an outbound path, we may immediately fulfill the
+ // corresponding HTLC on the inbound path. If, then, the outbound path channel is
+ // disconnected and reconnected (before we've exchange commitment_signed and revoke_and_ack
+ // messages), they may re-broadcast their update_fulfill_htlc, causing a duplicate claim. This
+ // is fine, but as a sanity check in our failure to generate the second claim, we check here
+ // that the original was a claim, and that we aren't now trying to fulfill a failed HTLC.
+ historical_inbound_htlc_fulfills: HashSet<u64>,
}
#[cfg(any(test, feature = "fuzztarget"))]
next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
workaround_lnd_bug_4006: None,
+
+ #[cfg(any(test, feature = "fuzztarget"))]
+ historical_inbound_htlc_fulfills: HashSet::new(),
})
}
next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
workaround_lnd_bug_4006: None,
+
+ #[cfg(any(test, feature = "fuzztarget"))]
+ historical_inbound_htlc_fulfills: HashSet::new(),
};
Ok(chan)
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,
if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
} else {
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");
}
- debug_assert!(false, "Tried to fulfill an HTLC that was already fail/fulfilled");
- 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 pending_idx == core::usize::MAX {
- return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
+ #[cfg(any(test, feature = "fuzztarget"))]
+ // 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 UpdateFulfillFetch::DuplicateClaim {};
}
// Now update local state:
if htlc_id_arg == htlc_id {
// Make sure we don't leave latest_monitor_update_id incremented here:
self.latest_monitor_update_id -= 1;
- debug_assert!(false, "Tried to fulfill an HTLC that was already fulfilled");
- return Ok((None, None));
+ #[cfg(any(test, feature = "fuzztarget"))]
+ debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ 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 };
}
},
_ => {}
self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
});
- return Ok((None, Some(monitor_update)));
+ #[cfg(any(test, feature = "fuzztarget"))]
+ self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
+ return UpdateFulfillFetch::NewClaim { monitor_update, msg: None };
}
+ #[cfg(any(test, feature = "fuzztarget"))]
+ self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
{
let htlc = &mut self.pending_inbound_htlcs[pending_idx];
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)) => {
- let (commitment, mut additional_update) = self.send_commitment_no_status_check(logger)?;
+ pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<UpdateFulfillCommitFetch, (ChannelError, ChannelMonitorUpdate)> 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) = match self.send_commitment_no_status_check(logger) {
+ Err(e) => return Err((e, monitor_update)),
+ Ok(res) => res
+ };
// 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");
if htlc.htlc_id == htlc_id_arg {
match htlc.state {
InboundHTLCState::Committed => {},
- InboundHTLCState::LocalRemoved(_) => {
- debug_assert!(false, "Tried to fail an HTLC that was already fail/fulfilled");
+ InboundHTLCState::LocalRemoved(ref reason) => {
+ if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
+ } else {
+ debug_assert!(false, "Tried to fail an HTLC that was already failed");
+ }
return Ok(None);
},
_ => {
}
}
if pending_idx == core::usize::MAX {
- return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
+ #[cfg(any(test, feature = "fuzztarget"))]
+ // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
+ // is simply a duplicate fail, not previously failed and we failed-back too early.
+ debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ return Ok(None);
}
// Now update local state:
match pending_update {
&HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
if htlc_id_arg == htlc_id {
- debug_assert!(false, "Tried to fail an HTLC that was already fulfilled");
- return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
+ #[cfg(any(test, feature = "fuzztarget"))]
+ debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ return Ok(None);
}
},
&HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
}
},
&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) {
- Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
+ 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.
+ update_fail_htlcs.push(update_fail_msg_option.unwrap())
+ },
Err(e) => {
if let ChannelError::Ignore(_) = e {}
else {
self.channel_update_status.write(writer)?;
+ #[cfg(any(test, feature = "fuzztarget"))]
+ (self.historical_inbound_htlc_fulfills.len() as u64).write(writer)?;
+ #[cfg(any(test, feature = "fuzztarget"))]
+ for htlc in self.historical_inbound_htlc_fulfills.iter() {
+ htlc.write(writer)?;
+ }
+
write_tlv_fields!(writer, {
(0, self.announcement_sigs, option),
// minimum_depth and counterparty_selected_channel_reserve_satoshis used to have a
let channel_update_status = Readable::read(reader)?;
+ #[cfg(any(test, feature = "fuzztarget"))]
+ let mut historical_inbound_htlc_fulfills = HashSet::new();
+ #[cfg(any(test, feature = "fuzztarget"))]
+ {
+ let htlc_fulfills_len: u64 = Readable::read(reader)?;
+ for _ in 0..htlc_fulfills_len {
+ assert!(historical_inbound_htlc_fulfills.insert(Readable::read(reader)?));
+ }
+ }
+
let mut announcement_sigs = None;
read_tlv_fields!(reader, {
(0, announcement_sigs, option),
next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
workaround_lnd_bug_4006: None,
+
+ #[cfg(any(test, feature = "fuzztarget"))]
+ historical_inbound_htlc_fulfills,
})
}
}
projects / rust-lightning / blobdiff