Add prev_channel_outpoint to previous hop data
authorValentine Wallace <vwallace@protonmail.com>
Thu, 22 Oct 2020 17:32:50 +0000 (13:32 -0400)
committerValentine Wallace <vwallace@protonmail.com>
Thu, 12 Nov 2020 23:52:06 +0000 (18:52 -0500)
This will be used in upcoming commits to allow us to update a channel
monitor with a preimage after its channel has closed.

lightning/src/ln/channelmanager.rs

index b43c98c840392c7b983de276e0867ba5e3baf795..f3f13d3fb91f9f223651b396cd1acf5010b81163 100644 (file)
@@ -118,9 +118,15 @@ pub(super) enum PendingHTLCStatus {
 
 pub(super) enum HTLCForwardInfo {
        AddHTLC {
+               forward_info: PendingHTLCInfo,
+
+               // These fields are produced in `forward_htlcs()` and consumed in
+               // `process_pending_htlc_forwards()` for constructing the
+               // `HTLCSource::PreviousHopData` for failed and forwarded
+               // HTLCs.
                prev_short_channel_id: u64,
                prev_htlc_id: u64,
-               forward_info: PendingHTLCInfo,
+               prev_funding_outpoint: OutPoint,
        },
        FailHTLC {
                htlc_id: u64,
@@ -134,6 +140,10 @@ pub(crate) struct HTLCPreviousHopData {
        short_channel_id: u64,
        htlc_id: u64,
        incoming_packet_shared_secret: [u8; 32],
+
+       // This field is consumed by `claim_funds_from_hop()` when updating a force-closed backwards
+       // channel with a preimage provided by the forward channel.
+       outpoint: OutPoint,
 }
 
 struct ClaimableHTLC {
@@ -1554,9 +1564,11 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                                        failed_forwards.reserve(pending_forwards.len());
                                                        for forward_info in pending_forwards.drain(..) {
                                                                match forward_info {
-                                                                       HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
+                                                                       HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info,
+                                                                                                  prev_funding_outpoint } => {
                                                                                let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
                                                                                        short_channel_id: prev_short_channel_id,
+                                                                                       outpoint: prev_funding_outpoint,
                                                                                        htlc_id: prev_htlc_id,
                                                                                        incoming_packet_shared_secret: forward_info.incoming_shared_secret,
                                                                                });
@@ -1583,10 +1595,12 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                                                HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
                                                                                routing: PendingHTLCRouting::Forward {
                                                                                        onion_packet, ..
-                                                                               }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value }, } => {
+                                                                               }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value },
+                                                                               prev_funding_outpoint } => {
                                                                        log_trace!(self.logger, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", log_bytes!(payment_hash.0), prev_short_channel_id, short_chan_id);
                                                                        let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
                                                                                short_channel_id: prev_short_channel_id,
+                                                                               outpoint: prev_funding_outpoint,
                                                                                htlc_id: prev_htlc_id,
                                                                                incoming_packet_shared_secret: incoming_shared_secret,
                                                                        });
@@ -1701,9 +1715,11 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                                match forward_info {
                                                        HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
                                                                        routing: PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry },
-                                                                       incoming_shared_secret, payment_hash, amt_to_forward, .. }, } => {
+                                                                       incoming_shared_secret, payment_hash, amt_to_forward, .. },
+                                                                       prev_funding_outpoint } => {
                                                                let prev_hop = HTLCPreviousHopData {
                                                                        short_channel_id: prev_short_channel_id,
+                                                                       outpoint: prev_funding_outpoint,
                                                                        htlc_id: prev_htlc_id,
                                                                        incoming_packet_shared_secret: incoming_shared_secret,
                                                                };
@@ -1738,6 +1754,7 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                                                                        );
                                                                                        failed_forwards.push((HTLCSource::PreviousHopData(HTLCPreviousHopData {
                                                                                                        short_channel_id: htlc.prev_hop.short_channel_id,
+                                                                                                       outpoint: prev_funding_outpoint,
                                                                                                        htlc_id: htlc.prev_hop.htlc_id,
                                                                                                        incoming_packet_shared_secret: htlc.prev_hop.incoming_packet_shared_secret,
                                                                                                }), payment_hash,
@@ -1940,7 +1957,7 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                        }
                                }
                        },
-                       HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
+                       HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret, .. }) => {
                                let err_packet = match onion_error {
                                        HTLCFailReason::Reason { failure_code, data } => {
                                                log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
@@ -2201,7 +2218,7 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
 
                        let (raa, commitment_update, order, pending_forwards, mut pending_failures, needs_broadcast_safe, funding_locked) = channel.monitor_updating_restored(&self.logger);
                        if !pending_forwards.is_empty() {
-                               htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
+                               htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), funding_txo.clone(), pending_forwards));
                        }
                        htlc_failures.append(&mut pending_failures);
 
@@ -2685,8 +2702,8 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
        }
 
        #[inline]
-       fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingHTLCInfo, u64)>)]) {
-               for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
+       fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, OutPoint, Vec<(PendingHTLCInfo, u64)>)]) {
+               for &mut (prev_short_channel_id, prev_funding_outpoint, ref mut pending_forwards) in per_source_pending_forwards {
                        let mut forward_event = None;
                        if !pending_forwards.is_empty() {
                                let mut channel_state = self.channel_state.lock().unwrap();
@@ -2699,10 +2716,12 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                                        PendingHTLCRouting::Receive { .. } => 0,
                                        }) {
                                                hash_map::Entry::Occupied(mut entry) => {
-                                                       entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
+                                                       entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_funding_outpoint,
+                                                                                                       prev_htlc_id, forward_info });
                                                },
                                                hash_map::Entry::Vacant(entry) => {
-                                                       entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
+                                                       entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_funding_outpoint,
+                                                                                                    prev_htlc_id, forward_info }));
                                                }
                                        }
                                }
@@ -2755,18 +2774,18 @@ impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                                        msg,
                                                });
                                        }
-                                       break Ok((pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel")))
+                                       break Ok((pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"), chan.get().get_funding_txo().unwrap()))
                                },
                                hash_map::Entry::Vacant(_) => break Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
                        }
                };
                self.fail_holding_cell_htlcs(htlcs_to_fail, msg.channel_id);
                match res {
-                       Ok((pending_forwards, mut pending_failures, short_channel_id)) => {
+                       Ok((pending_forwards, mut pending_failures, short_channel_id, channel_outpoint)) => {
                                for failure in pending_failures.drain(..) {
                                        self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
                                }
-                               self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
+                               self.forward_htlcs(&mut [(short_channel_id, channel_outpoint, pending_forwards)]);
                                Ok(())
                        },
                        Err(e) => Err(e)
@@ -3543,6 +3562,7 @@ impl Readable for PendingHTLCStatus {
 
 impl_writeable!(HTLCPreviousHopData, 0, {
        short_channel_id,
+       outpoint,
        htlc_id,
        incoming_packet_shared_secret
 });
@@ -3619,9 +3639,10 @@ impl Readable for HTLCFailReason {
 impl Writeable for HTLCForwardInfo {
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
                match self {
-                       &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
+                       &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_funding_outpoint, ref prev_htlc_id, ref forward_info } => {
                                0u8.write(writer)?;
                                prev_short_channel_id.write(writer)?;
+                               prev_funding_outpoint.write(writer)?;
                                prev_htlc_id.write(writer)?;
                                forward_info.write(writer)?;
                        },
@@ -3640,6 +3661,7 @@ impl Readable for HTLCForwardInfo {
                match <u8 as Readable>::read(reader)? {
                        0 => Ok(HTLCForwardInfo::AddHTLC {
                                prev_short_channel_id: Readable::read(reader)?,
+                               prev_funding_outpoint: Readable::read(reader)?,
                                prev_htlc_id: Readable::read(reader)?,
                                forward_info: Readable::read(reader)?,
                        }),