tForward HTLCs - electrum - Electrum Bitcoin wallet
HTML git clone https://git.parazyd.org/electrum
DIR Log
DIR Files
DIR Refs
DIR Submodules
---
DIR commit 43e6e08840e92207ab5eb14bfb4d418074e8a148
DIR parent a975ac1571e1ec6375cd5cd5284f0fdd5fb0dc83
HTML Author: ThomasV <thomasv@electrum.org>
Date: Sun, 3 Feb 2019 08:00:44 +0100
Forward HTLCs
Diffstat:
M electrum/lnbase.py | 34 +++++++++++++++++++++++++++----
1 file changed, 30 insertions(+), 4 deletions(-)
---
DIR diff --git a/electrum/lnbase.py b/electrum/lnbase.py
t@@ -1066,11 +1066,37 @@ class Peer(PrintError):
htlc = {'amount_msat': amount_msat_htlc, 'payment_hash':payment_hash, 'cltv_expiry':cltv_expiry}
htlc_id = chan.receive_htlc(htlc)
await self.receive_and_revoke(chan)
- # maybe fail htlc
+ # Forward HTLC
+ # FIXME: this is not robust to us going offline before payment is fulfilled
if not processed_onion.are_we_final:
- # no forwarding for now
- reason = OnionRoutingFailureMessage(code=OnionFailureCode.PERMANENT_CHANNEL_FAILURE, data=b'')
- await self.fail_htlc(chan, htlc_id, onion_packet, reason)
+ dph = processed_onion.hop_data.per_hop
+ next_chan = self.lnworker.get_channel_by_short_id(dph.short_channel_id)
+ next_peer = self.lnworker.peers[next_chan.node_id]
+ if next_chan is None or next_chan.get_state() != 'OPEN':
+ self.print_error("cannot forward htlc", next_chan.get_state() if next_chan else None)
+ reason = OnionRoutingFailureMessage(code=OnionFailureCode.PERMANENT_CHANNEL_FAILURE, data=b'')
+ await self.fail_htlc(chan, htlc_id, onion_packet, reason)
+ return
+ self.print_error('forwarding htlc to', next_chan.node_id)
+ next_cltv_expiry = int.from_bytes(dph.outgoing_cltv_value, 'big')
+ next_amount_msat_htlc = int.from_bytes(dph.amt_to_forward, 'big')
+ next_htlc = {'amount_msat':next_amount_msat_htlc, 'payment_hash':payment_hash, 'cltv_expiry':next_cltv_expiry}
+ next_htlc_id = next_chan.add_htlc(next_htlc)
+ next_peer.send_message(
+ "update_add_htlc",
+ channel_id=next_chan.channel_id,
+ id=next_htlc_id,
+ cltv_expiry=dph.outgoing_cltv_value,
+ amount_msat=dph.amt_to_forward,
+ payment_hash=payment_hash,
+ onion_routing_packet=processed_onion.next_packet.to_bytes()
+ )
+ await next_peer.send_and_revoke(next_chan)
+ # wait until we get paid
+ preimage = await next_peer.payment_preimages[payment_hash].get()
+ # fulfill the original htlc
+ await self.fulfill_htlc(chan, htlc_id, preimage)
+ self.print_error("htlc forwarded successfully")
return
try:
preimage, invoice = self.lnworker.get_invoice(payment_hash)