#[derive(PartialEq)]
enum HTLCState {
/// Added by remote, to be included in next local commitment tx.
+ /// Implies HTLCOutput::outbound: false
RemoteAnnounced,
/// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but
/// the remote side hasn't yet revoked their previous state, which we need them to do before we
/// accept this HTLC. Implies AwaitingRemoteRevoke.
/// We also have not yet included this HTLC in a commitment_signed message, and are waiting on
/// a remote revoke_and_ack on a previous state before we can do so.
+ /// Implies HTLCOutput::outbound: false
AwaitingRemoteRevokeToAnnounce,
/// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but
/// the remote side hasn't yet revoked their previous state, which we need them to do before we
/// accept this HTLC. Implies AwaitingRemoteRevoke.
/// We have included this HTLC in our latest commitment_signed and are now just waiting on a
/// revoke_and_ack.
+ /// Implies HTLCOutput::outbound: true
AwaitingAnnouncedRemoteRevoke,
/// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
/// created it we would have put it in the holding cell instead). When they next revoke_and_ack
/// allowed to remove it, the "can only be removed once committed on both sides" requirement
/// doesn't matter to us and its up to them to enforce it, worst-case they jump ahead but
/// we'll never get out of sync).
+ /// Implies HTLCOutput::outbound: true
LocalAnnounced,
Committed,
/// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
/// the change (though they'll need to revoke before we fail the payment).
+ /// Implies HTLCOutput::outbound: true
RemoteRemoved,
/// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
/// the remote side hasn't yet revoked their previous state, which we need them to do before we
/// can do any backwards failing. Implies AwaitingRemoteRevoke.
/// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
/// remote revoke_and_ack on a previous state before we can do so.
+ /// Implies HTLCOutput::outbound: true
AwaitingRemoteRevokeToRemove,
/// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
/// the remote side hasn't yet revoked their previous state, which we need them to do before we
/// can do any backwards failing. Implies AwaitingRemoteRevoke.
/// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
/// revoke_and_ack to drop completely.
+ /// Implies HTLCOutput::outbound: true
AwaitingRemovedRemoteRevoke,
/// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
/// created it we would have put it in the holding cell instead). When they next revoke_and_ack
/// commitment transaction without it as otherwise we'll have to force-close the channel to
/// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
/// anyway).
+ /// Implies HTLCOutput::outbound: false
LocalRemoved,
/// Removed by us, sent a new commitment_signed and got a revoke_and_ack. Just waiting on an
/// updated local commitment transaction. Implies local_removed_fulfilled.
+ /// Implies HTLCOutput::outbound: false
LocalRemovedAwaitingCommitment,
}
for (idx, htlc) in self.pending_htlcs.iter().enumerate() {
if !htlc.outbound && htlc.payment_hash == payment_hash_calc {
if pending_idx != std::usize::MAX {
- panic!("Duplicate HTLC payment_hash, you probably re-used payment preimages, NEVER DO THIS!");
+ panic!("Duplicate HTLC payment_hash, ChannelManager should have prevented this!");
}
pending_idx = idx;
}
if htlc.state == HTLCState::Committed {
htlc.state = HTLCState::LocalRemoved;
htlc.local_removed_fulfilled = true;
- } else if htlc.state == HTLCState::RemoteAnnounced {
- panic!("Somehow forwarded HTLC prior to remote revocation!");
+ } else if htlc.state == HTLCState::RemoteAnnounced || htlc.state == HTLCState::AwaitingRemoteRevokeToAnnounce || htlc.state == HTLCState::AwaitingAnnouncedRemoteRevoke {
+ // Theoretically we can hit this if we get the preimage on an HTLC prior to us
+ // having forwarded it to anyone. This implies that the sender is busted as someone
+ // else knows the preimage, but handling this case and implementing the logic to
+ // take their money would be a lot of (never-tested) code to handle a case that
+ // hopefully never happens. Instead, we make sure we get the preimage into the
+ // channel_monitor and pretend we didn't just see the preimage.
+ return Ok((None, Some(self.channel_monitor.clone())));
} else if htlc.state == HTLCState::LocalRemoved || htlc.state == HTLCState::LocalRemovedAwaitingCommitment {
return Err(HandleError{err: "Unable to find a pending HTLC which matched the given payment preimage", action: None});
} else {
projects / rust-lightning / commitdiff