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fix multi-hop payments

regtest_lnd
SomberNight 6 years ago
parent
commit
241339971a
No known key found for this signature in database GPG Key ID: B33B5F232C6271E9
  1. 42
      electrum/lnbase.py
  2. 5
      electrum/lnrouter.py

42
electrum/lnbase.py

@ -880,6 +880,7 @@ class Peer(PrintError):
code = OnionFailureCode(failure_msg.code)
data = failure_msg.data
self.print_error("UPDATE_FAIL_HTLC", repr(code), data)
self.print_error(f"error reported by {bh2u(route[sender_idx].node_id)}")
# handle some specific error codes
failure_codes = {
OnionFailureCode.TEMPORARY_CHANNEL_FAILURE: 2,
@ -894,9 +895,12 @@ class Peer(PrintError):
channel_update = (258).to_bytes(length=2, byteorder="big") + data[offset:]
message_type, payload = decode_msg(channel_update)
try:
self.print_error("trying to apply channel update on our db", payload)
self.channel_db.on_channel_update(payload)
self.print_error("successfully applied channel update on our db")
except NotFoundChanAnnouncementForUpdate:
# maybe it is a private channel (and data in invoice was outdated)
self.print_error("maybe channel update is for private channel?")
start_node_id = route[sender_idx].node_id
self.channel_db.add_channel_update_for_private_channel(payload, start_node_id)
else:
@ -923,29 +927,41 @@ class Peer(PrintError):
await self.receive_commitment(chan)
self.revoke(chan)
def calc_hops_data_for_payment(self, route: List[RouteEdge], amount_msat: int, min_final_cltv_expiry: int):
"""Returns the hops_data to be used for constructing an onion packet,
and the amount_msat and cltv to be used on our immediate channel.
"""
amt = amount_msat
height = self.network.get_local_height()
cltv = height + min_final_cltv_expiry
hops_data = [OnionHopsDataSingle(OnionPerHop(b"\x00" * 8,
amt.to_bytes(8, "big"),
cltv.to_bytes(4, "big")))]
for route_edge in reversed(route[1:]):
hops_data += [OnionHopsDataSingle(OnionPerHop(route_edge.short_channel_id,
amt.to_bytes(8, "big"),
cltv.to_bytes(4, "big")))]
amt += route_edge.fee_for_edge(amt)
cltv += route_edge.cltv_expiry_delta
hops_data.reverse()
return hops_data, amt, cltv
async def pay(self, route: List[RouteEdge], chan, amount_msat, payment_hash, min_final_cltv_expiry):
assert chan.get_state() == "OPEN", chan.get_state()
assert amount_msat > 0, "amount_msat is not greater zero"
height = self.network.get_local_height()
hops_data = []
sum_of_deltas = sum(route_edge.cltv_expiry_delta for route_edge in route[1:])
total_fee = 0
final_cltv_expiry_without_deltas = (height + min_final_cltv_expiry)
final_cltv_expiry_with_deltas = final_cltv_expiry_without_deltas + sum_of_deltas
for idx, route_edge in enumerate(route[1:]):
hops_data += [OnionHopsDataSingle(OnionPerHop(route_edge.short_channel_id, amount_msat.to_bytes(8, "big"), final_cltv_expiry_without_deltas.to_bytes(4, "big")))]
total_fee += route_edge.fee_base_msat + ( amount_msat * route_edge.fee_proportional_millionths // 1000000 )
# create onion packet
hops_data, amount_msat, cltv = self.calc_hops_data_for_payment(route, amount_msat, min_final_cltv_expiry)
associated_data = payment_hash
secret_key = os.urandom(32)
hops_data += [OnionHopsDataSingle(OnionPerHop(b"\x00"*8, amount_msat.to_bytes(8, "big"), (final_cltv_expiry_without_deltas).to_bytes(4, "big")))]
onion = new_onion_packet([x.node_id for x in route], secret_key, hops_data, associated_data)
amount_msat += total_fee
chan.check_can_pay(amount_msat)
htlc = {'amount_msat':amount_msat, 'payment_hash':payment_hash, 'cltv_expiry':final_cltv_expiry_with_deltas}
# create htlc
htlc = {'amount_msat':amount_msat, 'payment_hash':payment_hash, 'cltv_expiry':cltv}
htlc_id = chan.add_htlc(htlc)
chan.onion_keys[htlc_id] = secret_key
self.attempted_route[(chan.channel_id, htlc_id)] = route
await self.update_channel(chan, "update_add_htlc", channel_id=chan.channel_id, id=htlc_id, cltv_expiry=final_cltv_expiry_with_deltas, amount_msat=amount_msat, payment_hash=payment_hash, onion_routing_packet=onion.to_bytes())
self.print_error(f"starting payment. route: {route}")
await self.update_channel(chan, "update_add_htlc", channel_id=chan.channel_id, id=htlc_id, cltv_expiry=cltv, amount_msat=amount_msat, payment_hash=payment_hash, onion_routing_packet=onion.to_bytes())
async def receive_revoke(self, m):
revoke_and_ack_msg = await self.revoke_and_ack[m.channel_id].get()

5
electrum/lnrouter.py

@ -501,7 +501,10 @@ class RouteEdge(NamedTuple("RouteEdge", [('node_id', bytes),
('fee_proportional_millionths', int),
('cltv_expiry_delta', int)])):
"""if you travel through short_channel_id, you will reach node_id"""
pass
def fee_for_edge(self, amount_msat):
return self.fee_base_msat \
+ (amount_msat * self.fee_proportional_millionths // 1_000_000)
class LNPathFinder(PrintError):

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