lukechilds
/
electrum
mirror of https://github.com/lukechilds/electrum.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
10991 Commits
21 Branches
132 Tags
52 MiB
 
 
 
 
Tree: 256dab53ad
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from '256dab53ad'
${ noResults }
electrum/electrum/lnpeer.py

1169 lines
61 KiB
Raw Blame History

#!/usr/bin/env python3
#
# Copyright (C) 2018 The Electrum developers
# Distributed under the MIT software license, see the accompanying
# file LICENCE or http://www.opensource.org/licenses/mit-license.php
import zlib
from collections import OrderedDict, defaultdict
import json
import asyncio
import os
import time
from functools import partial
from typing import List, Tuple, Dict, TYPE_CHECKING, Optional, Callable
import traceback
import sys
import aiorpcx
from .simple_config import get_config
from .crypto import sha256, sha256d
from . import bitcoin
from . import ecc
from .ecc import sig_string_from_r_and_s, get_r_and_s_from_sig_string, der_sig_from_sig_string
from . import constants
from .util import PrintError, bh2u, print_error, bfh, log_exceptions, list_enabled_bits, ignore_exceptions
from .transaction import Transaction, TxOutput
from .lnonion import (new_onion_packet, decode_onion_error, OnionFailureCode, calc_hops_data_for_payment,
process_onion_packet, OnionPacket, construct_onion_error, OnionRoutingFailureMessage,
ProcessedOnionPacket)
from .lnchannel import Channel, RevokeAndAck, htlcsum
from .lnutil import (Outpoint, LocalConfig, RECEIVED, UpdateAddHtlc,
RemoteConfig, OnlyPubkeyKeypair, ChannelConstraints, RevocationStore,
funding_output_script, get_per_commitment_secret_from_seed,
secret_to_pubkey, PaymentFailure, LnLocalFeatures,
LOCAL, REMOTE, HTLCOwner, generate_keypair, LnKeyFamily,
get_ln_flag_pair_of_bit, privkey_to_pubkey, UnknownPaymentHash, MIN_FINAL_CLTV_EXPIRY_ACCEPTED,
LightningPeerConnectionClosed, HandshakeFailed, NotFoundChanAnnouncementForUpdate,
MINIMUM_MAX_HTLC_VALUE_IN_FLIGHT_ACCEPTED, MAXIMUM_HTLC_MINIMUM_MSAT_ACCEPTED,
MAXIMUM_REMOTE_TO_SELF_DELAY_ACCEPTED, RemoteMisbehaving)
from .lntransport import LNTransport, LNTransportBase
from .lnmsg import encode_msg, decode_msg
if TYPE_CHECKING:
from .lnworker import LNWorker
from .lnrouter import RouteEdge
def channel_id_from_funding_tx(funding_txid: str, funding_index: int) -> Tuple[bytes, bytes]:
funding_txid_bytes = bytes.fromhex(funding_txid)[::-1]
i = int.from_bytes(funding_txid_bytes, 'big') ^ funding_index
return i.to_bytes(32, 'big'), funding_txid_bytes
class Peer(PrintError):
def __init__(self, lnworker: 'LNWorker', pubkey:bytes, transport: LNTransportBase,
request_initial_sync=False):
self.initialized = asyncio.Event()
self.node_anns = []
self.chan_anns = []
self.chan_upds = []
self.transport = transport
self.pubkey = pubkey
self.lnworker = lnworker
self.privkey = lnworker.node_keypair.privkey
self.node_ids = [self.pubkey, privkey_to_pubkey(self.privkey)]
self.network = lnworker.network
self.lnwatcher = lnworker.network.lnwatcher
self.channel_db = lnworker.network.channel_db
self.ping_time = 0
self.shutdown_received = defaultdict(asyncio.Future)
self.channel_accepted = defaultdict(asyncio.Queue)
self.channel_reestablished = defaultdict(asyncio.Future)
self.funding_signed = defaultdict(asyncio.Queue)
self.funding_created = defaultdict(asyncio.Queue)
self.announcement_signatures = defaultdict(asyncio.Queue)
self.closing_signed = defaultdict(asyncio.Queue)
self.payment_preimages = defaultdict(asyncio.Queue)
self.localfeatures = LnLocalFeatures(0)
if request_initial_sync:
self.localfeatures |= LnLocalFeatures.INITIAL_ROUTING_SYNC
self.localfeatures |= LnLocalFeatures.OPTION_DATA_LOSS_PROTECT_REQ
self.attempted_route = {}
self.orphan_channel_updates = OrderedDict()
self.sent_commitment_for_ctn_last = defaultdict(lambda: None) # type: Dict[Channel, Optional[int]]
self.recv_commitment_for_ctn_last = defaultdict(lambda: None) # type: Dict[Channel, Optional[int]]
self._local_changed_events = defaultdict(asyncio.Event)
self._remote_changed_events = defaultdict(asyncio.Event)
self.receiving_channels = False
def send_message(self, message_name: str, **kwargs):
assert type(message_name) is str
self.print_error("Sending '%s'"%message_name.upper())
self.transport.send_bytes(encode_msg(message_name, **kwargs))
async def initialize(self):
if isinstance(self.transport, LNTransport):
await self.transport.handshake()
self.channel_db.add_recent_peer(self.transport.peer_addr)
self.send_message("init", gflen=0, lflen=1, localfeatures=self.localfeatures)
@property
def channels(self) -> Dict[bytes, Channel]:
return self.lnworker.channels_for_peer(self.pubkey)
def diagnostic_name(self):
return self.transport.name()
def ping_if_required(self):
if time.time() - self.ping_time > 120:
self.send_message('ping', num_pong_bytes=4, byteslen=4)
self.ping_time = time.time()
def process_message(self, message):
message_type, payload = decode_msg(message)
try:
f = getattr(self, 'on_' + message_type)
except AttributeError:
#self.print_error("Received '%s'" % message_type.upper(), payload)
return
# raw message is needed to check signature
if message_type=='node_announcement':
payload['raw'] = message
execution_result = f(payload)
if asyncio.iscoroutinefunction(f):
asyncio.ensure_future(execution_result)
def on_error(self, payload):
# todo: self.channel_reestablished is not a queue
self.print_error("error", payload["data"].decode("ascii"))
chan_id = payload.get("channel_id")
for d in [ self.channel_accepted, self.funding_signed,
self.funding_created,
self.announcement_signatures, self.closing_signed ]:
if chan_id in d:
d[chan_id].put_nowait({'error':payload['data']})
def on_ping(self, payload):
l = int.from_bytes(payload['num_pong_bytes'], 'big')
self.send_message('pong', byteslen=l)
def on_pong(self, payload):
pass
def on_accept_channel(self, payload):
temp_chan_id = payload["temporary_channel_id"]
if temp_chan_id not in self.channel_accepted: raise Exception("Got unknown accept_channel")
self.channel_accepted[temp_chan_id].put_nowait(payload)
def on_funding_signed(self, payload):
channel_id = payload['channel_id']
if channel_id not in self.funding_signed: raise Exception("Got unknown funding_signed")
self.funding_signed[channel_id].put_nowait(payload)
def on_funding_created(self, payload):
channel_id = payload['temporary_channel_id']
if channel_id not in self.funding_created: raise Exception("Got unknown funding_created")
self.funding_created[channel_id].put_nowait(payload)
def on_init(self, payload):
if self.initialized.is_set():
self.print_error("ALREADY INITIALIZED BUT RECEIVED INIT")
return
# if they required some even flag we don't have, they will close themselves
# but if we require an even flag they don't have, we close
our_flags = set(list_enabled_bits(self.localfeatures))
their_flags = set(list_enabled_bits(int.from_bytes(payload['localfeatures'], byteorder="big")))
for flag in our_flags:
if flag not in their_flags and get_ln_flag_pair_of_bit(flag) not in their_flags:
# they don't have this feature we wanted :(
if flag % 2 == 0: # even flags are compulsory
raise LightningPeerConnectionClosed("remote does not have even flag {}"
.format(str(LnLocalFeatures(1 << flag))))
self.localfeatures ^= 1 << flag # disable flag
first_timestamp = self.lnworker.get_first_timestamp()
self.send_message('gossip_timestamp_filter', chain_hash=constants.net.rev_genesis_bytes(), first_timestamp=first_timestamp, timestamp_range=b"\xff"*4)
self.initialized.set()
def on_node_announcement(self, payload):
self.node_anns.append(payload)
def on_channel_update(self, payload):
self.chan_upds.append(payload)
def on_channel_announcement(self, payload):
self.chan_anns.append(payload)
def on_announcement_signatures(self, payload):
channel_id = payload['channel_id']
chan = self.channels[payload['channel_id']]
if chan.config[LOCAL].was_announced:
h, local_node_sig, local_bitcoin_sig = self.send_announcement_signatures(chan)
else:
self.announcement_signatures[channel_id].put_nowait(payload)
def handle_disconnect(func):
async def wrapper_func(self, *args, **kwargs):
try:
return await func(self, *args, **kwargs)
except LightningPeerConnectionClosed as e:
self.print_error("disconnecting gracefully. {}".format(e))
finally:
self.close_and_cleanup()
self.lnworker.peers.pop(self.pubkey)
return wrapper_func
@ignore_exceptions # do not kill main_taskgroup
@log_exceptions
@handle_disconnect
async def main_loop(self):
async with aiorpcx.TaskGroup() as group:
await group.spawn(self._gossip_loop())
await group.spawn(self._message_loop())
async def _gossip_loop(self):
await self.initialized.wait()
while True:
await asyncio.sleep(5)
if self.node_anns:
self.channel_db.on_node_announcement(self.node_anns)
self.node_anns = []
if self.chan_anns:
self.channel_db.on_channel_announcement(self.chan_anns)
self.chan_anns = []
if self.chan_upds:
self.channel_db.on_channel_update(self.chan_upds)
self.chan_upds = []
need_to_get = self.channel_db.missing_short_chan_ids() #type: Set[int]
if need_to_get and not self.receiving_channels:
self.print_error('QUERYING SHORT CHANNEL IDS; missing', len(need_to_get), 'channels')
zlibencoded = zlib.compress(bfh(''.join(need_to_get)))
self.send_message('query_short_channel_ids', chain_hash=bytes.fromhex(bitcoin.rev_hex(constants.net.GENESIS)), len=1+len(zlibencoded), encoded_short_ids=b'\x01' + zlibencoded)
self.receiving_channels = True
async def _message_loop(self):
try:
await asyncio.wait_for(self.initialize(), 10)
except (OSError, asyncio.TimeoutError, HandshakeFailed) as e:
self.print_error('initialize failed, disconnecting: {}'.format(repr(e)))
return
# loop
async for msg in self.transport.read_messages():
self.process_message(msg)
await asyncio.sleep(.01)
self.ping_if_required()
def on_reply_short_channel_ids_end(self, payload):
self.receiving_channels = False
def close_and_cleanup(self):
try:
if self.transport:
self.transport.close()
except:
pass
for chan in self.channels.values():
if chan.get_state() != 'FORCE_CLOSING':
chan.set_state('DISCONNECTED')
self.network.trigger_callback('channel', chan)
def make_local_config(self, funding_sat: int, push_msat: int, initiator: HTLCOwner) -> LocalConfig:
# key derivation
channel_counter = self.lnworker.get_and_inc_counter_for_channel_keys()
keypair_generator = lambda family: generate_keypair(self.lnworker.ln_keystore, family, channel_counter)
if initiator == LOCAL:
initial_msat = funding_sat * 1000 - push_msat
else:
initial_msat = push_msat
local_config=LocalConfig(
payment_basepoint=keypair_generator(LnKeyFamily.PAYMENT_BASE),
multisig_key=keypair_generator(LnKeyFamily.MULTISIG),
htlc_basepoint=keypair_generator(LnKeyFamily.HTLC_BASE),
delayed_basepoint=keypair_generator(LnKeyFamily.DELAY_BASE),
revocation_basepoint=keypair_generator(LnKeyFamily.REVOCATION_BASE),
to_self_delay=9,
dust_limit_sat=546,
max_htlc_value_in_flight_msat=funding_sat * 1000,
max_accepted_htlcs=5,
initial_msat=initial_msat,
ctn=-1,
next_htlc_id=0,
reserve_sat=546,
per_commitment_secret_seed=keypair_generator(LnKeyFamily.REVOCATION_ROOT).privkey,
funding_locked_received=False,
was_announced=False,
current_commitment_signature=None,
current_htlc_signatures=[],
got_sig_for_next=False,
)
return local_config
@log_exceptions
async def channel_establishment_flow(self, password: Optional[str], funding_sat: int,
push_msat: int, temp_channel_id: bytes) -> Channel:
wallet = self.lnworker.wallet
# dry run creating funding tx to see if we even have enough funds
funding_tx_test = wallet.mktx([TxOutput(bitcoin.TYPE_ADDRESS, wallet.dummy_address(), funding_sat)],
password, self.lnworker.config, nonlocal_only=True)
await asyncio.wait_for(self.initialized.wait(), 1)
feerate = self.lnworker.current_feerate_per_kw()
local_config = self.make_local_config(funding_sat, push_msat, LOCAL)
# for the first commitment transaction
per_commitment_secret_first = get_per_commitment_secret_from_seed(local_config.per_commitment_secret_seed,
RevocationStore.START_INDEX)
per_commitment_point_first = secret_to_pubkey(int.from_bytes(per_commitment_secret_first, 'big'))
self.send_message(
"open_channel",
temporary_channel_id=temp_channel_id,
chain_hash=constants.net.rev_genesis_bytes(),
funding_satoshis=funding_sat,
push_msat=push_msat,
dust_limit_satoshis=local_config.dust_limit_sat,
feerate_per_kw=feerate,
max_accepted_htlcs=local_config.max_accepted_htlcs,
funding_pubkey=local_config.multisig_key.pubkey,
revocation_basepoint=local_config.revocation_basepoint.pubkey,
htlc_basepoint=local_config.htlc_basepoint.pubkey,
payment_basepoint=local_config.payment_basepoint.pubkey,
delayed_payment_basepoint=local_config.delayed_basepoint.pubkey,
first_per_commitment_point=per_commitment_point_first,
to_self_delay=local_config.to_self_delay,
max_htlc_value_in_flight_msat=local_config.max_htlc_value_in_flight_msat,
channel_flags=0x00, # not willing to announce channel
channel_reserve_satoshis=local_config.reserve_sat,
htlc_minimum_msat=1,
)
payload = await asyncio.wait_for(self.channel_accepted[temp_channel_id].get(), 1)
if payload.get('error'):
raise Exception('Remote Lightning peer reported error: ' + repr(payload.get('error')))
remote_per_commitment_point = payload['first_per_commitment_point']
funding_txn_minimum_depth = int.from_bytes(payload['minimum_depth'], 'big')
assert funding_txn_minimum_depth > 0, funding_txn_minimum_depth
remote_dust_limit_sat = int.from_bytes(payload['dust_limit_satoshis'], byteorder='big')
remote_reserve_sat = self.validate_remote_reserve(payload["channel_reserve_satoshis"], remote_dust_limit_sat, funding_sat)
if remote_dust_limit_sat > remote_reserve_sat:
raise Exception(f"Remote Lightning peer reports dust_limit_sat > reserve_sat which is a BOLT-02 protocol violation.")
htlc_min = int.from_bytes(payload['htlc_minimum_msat'], 'big')
if htlc_min > MAXIMUM_HTLC_MINIMUM_MSAT_ACCEPTED:
raise Exception(f"Remote Lightning peer reports htlc_minimum_msat={htlc_min} mSAT," +
f" which is above Electrums required maximum limit of that parameter ({MAXIMUM_HTLC_MINIMUM_MSAT_ACCEPTED} mSAT).")
remote_max = int.from_bytes(payload['max_htlc_value_in_flight_msat'], 'big')
if remote_max < MINIMUM_MAX_HTLC_VALUE_IN_FLIGHT_ACCEPTED:
raise Exception(f"Remote Lightning peer reports max_htlc_value_in_flight_msat at only {remote_max} mSAT" +
f" which is below Electrums required minimum ({MINIMUM_MAX_HTLC_VALUE_IN_FLIGHT_ACCEPTED} mSAT).")
max_accepted_htlcs = int.from_bytes(payload["max_accepted_htlcs"], 'big')
if max_accepted_htlcs > 483:
raise Exception("Remote Lightning peer reports max_accepted_htlcs > 483, which is a BOLT-02 protocol violation.")
remote_to_self_delay = int.from_bytes(payload['to_self_delay'], byteorder='big')
if remote_to_self_delay > MAXIMUM_REMOTE_TO_SELF_DELAY_ACCEPTED:
raise Exception(f"Remote Lightning peer reports to_self_delay={remote_to_self_delay}," +
f" which is above Electrums required maximum ({MAXIMUM_REMOTE_TO_SELF_DELAY_ACCEPTED})")
their_revocation_store = RevocationStore()
remote_config = RemoteConfig(
payment_basepoint=OnlyPubkeyKeypair(payload['payment_basepoint']),
multisig_key=OnlyPubkeyKeypair(payload["funding_pubkey"]),
htlc_basepoint=OnlyPubkeyKeypair(payload['htlc_basepoint']),
delayed_basepoint=OnlyPubkeyKeypair(payload['delayed_payment_basepoint']),
revocation_basepoint=OnlyPubkeyKeypair(payload['revocation_basepoint']),
to_self_delay=remote_to_self_delay,
dust_limit_sat=remote_dust_limit_sat,
max_htlc_value_in_flight_msat=remote_max,
max_accepted_htlcs=max_accepted_htlcs,
initial_msat=push_msat,
ctn = -1,
next_htlc_id = 0,
reserve_sat = remote_reserve_sat,
htlc_minimum_msat = htlc_min,
next_per_commitment_point=remote_per_commitment_point,
current_per_commitment_point=None,
revocation_store=their_revocation_store,
)
# create funding tx
redeem_script = funding_output_script(local_config, remote_config)
funding_address = bitcoin.redeem_script_to_address('p2wsh', redeem_script)
funding_output = TxOutput(bitcoin.TYPE_ADDRESS, funding_address, funding_sat)
funding_tx = wallet.mktx([funding_output], password, self.lnworker.config, nonlocal_only=True)
funding_txid = funding_tx.txid()
funding_index = funding_tx.outputs().index(funding_output)
# remote commitment transaction
channel_id, funding_txid_bytes = channel_id_from_funding_tx(funding_txid, funding_index)
chan_dict = {
"node_id": self.pubkey,
"channel_id": channel_id,
"short_channel_id": None,
"funding_outpoint": Outpoint(funding_txid, funding_index),
"remote_config": remote_config,
"local_config": local_config,
"constraints": ChannelConstraints(capacity=funding_sat, is_initiator=True, funding_txn_minimum_depth=funding_txn_minimum_depth, feerate=feerate),
"remote_commitment_to_be_revoked": None,
}
chan = Channel(chan_dict,
sweep_address=self.lnworker.sweep_address,
lnworker=self.lnworker)
chan.lnwatcher = self.lnwatcher
sig_64, _ = chan.sign_next_commitment()
self.send_message("funding_created",
temporary_channel_id=temp_channel_id,
funding_txid=funding_txid_bytes,
funding_output_index=funding_index,
signature=sig_64)
payload = await asyncio.wait_for(self.funding_signed[channel_id].get(), 1)
self.print_error('received funding_signed')
remote_sig = payload['signature']
chan.receive_new_commitment(remote_sig, [])
# broadcast funding tx
await asyncio.wait_for(self.network.broadcast_transaction(funding_tx), 1)
chan.remote_commitment_to_be_revoked = chan.pending_commitment(REMOTE)
chan.config[REMOTE] = chan.config[REMOTE]._replace(ctn=0, current_per_commitment_point=remote_per_commitment_point, next_per_commitment_point=None)
chan.config[LOCAL] = chan.config[LOCAL]._replace(ctn=0, current_commitment_signature=remote_sig, got_sig_for_next=False)
chan.set_state('OPENING')
chan.set_remote_commitment()
chan.set_local_commitment(chan.current_commitment(LOCAL))
return chan
async def on_open_channel(self, payload):
# payload['channel_flags']
if payload['chain_hash'] != constants.net.rev_genesis_bytes():
raise Exception('wrong chain_hash')
funding_sat = int.from_bytes(payload['funding_satoshis'], 'big')
push_msat = int.from_bytes(payload['push_msat'], 'big')
feerate = int.from_bytes(payload['feerate_per_kw'], 'big')
temp_chan_id = payload['temporary_channel_id']
local_config = self.make_local_config(funding_sat, push_msat, REMOTE)
# for the first commitment transaction
per_commitment_secret_first = get_per_commitment_secret_from_seed(local_config.per_commitment_secret_seed,
RevocationStore.START_INDEX)
per_commitment_point_first = secret_to_pubkey(int.from_bytes(per_commitment_secret_first, 'big'))
min_depth = 3
self.send_message('accept_channel',
temporary_channel_id=temp_chan_id,
dust_limit_satoshis=local_config.dust_limit_sat,
max_htlc_value_in_flight_msat=local_config.max_htlc_value_in_flight_msat,
channel_reserve_satoshis=local_config.reserve_sat,
htlc_minimum_msat=1000,
minimum_depth=min_depth,
to_self_delay=local_config.to_self_delay,
max_accepted_htlcs=local_config.max_accepted_htlcs,
funding_pubkey=local_config.multisig_key.pubkey,
revocation_basepoint=local_config.revocation_basepoint.pubkey,
payment_basepoint=local_config.payment_basepoint.pubkey,
delayed_payment_basepoint=local_config.delayed_basepoint.pubkey,
htlc_basepoint=local_config.htlc_basepoint.pubkey,
first_per_commitment_point=per_commitment_point_first,
)
funding_created = await self.funding_created[temp_chan_id].get()
funding_idx = int.from_bytes(funding_created['funding_output_index'], 'big')
funding_txid = bh2u(funding_created['funding_txid'][::-1])
channel_id, funding_txid_bytes = channel_id_from_funding_tx(funding_txid, funding_idx)
their_revocation_store = RevocationStore()
remote_balance_sat = funding_sat * 1000 - push_msat
remote_dust_limit_sat = int.from_bytes(payload['dust_limit_satoshis'], byteorder='big') # TODO validate
remote_reserve_sat = self.validate_remote_reserve(payload['channel_reserve_satoshis'], remote_dust_limit_sat, funding_sat)
chan_dict = {
"node_id": self.pubkey,
"channel_id": channel_id,
"short_channel_id": None,
"funding_outpoint": Outpoint(funding_txid, funding_idx),
"remote_config": RemoteConfig(
payment_basepoint=OnlyPubkeyKeypair(payload['payment_basepoint']),
multisig_key=OnlyPubkeyKeypair(payload['funding_pubkey']),
htlc_basepoint=OnlyPubkeyKeypair(payload['htlc_basepoint']),
delayed_basepoint=OnlyPubkeyKeypair(payload['delayed_payment_basepoint']),
revocation_basepoint=OnlyPubkeyKeypair(payload['revocation_basepoint']),
to_self_delay=int.from_bytes(payload['to_self_delay'], 'big'),
dust_limit_sat=remote_dust_limit_sat,
max_htlc_value_in_flight_msat=int.from_bytes(payload['max_htlc_value_in_flight_msat'], 'big'), # TODO validate
max_accepted_htlcs=int.from_bytes(payload['max_accepted_htlcs'], 'big'), # TODO validate
initial_msat=remote_balance_sat,
ctn = -1,
next_htlc_id = 0,
reserve_sat = remote_reserve_sat,
htlc_minimum_msat=int.from_bytes(payload['htlc_minimum_msat'], 'big'), # TODO validate
next_per_commitment_point=payload['first_per_commitment_point'],
current_per_commitment_point=None,
revocation_store=their_revocation_store,
),
"local_config": local_config,
"constraints": ChannelConstraints(capacity=funding_sat, is_initiator=False, funding_txn_minimum_depth=min_depth, feerate=feerate),
"remote_commitment_to_be_revoked": None,
}
chan = Channel(chan_dict,
sweep_address=self.lnworker.sweep_address,
lnworker=self.lnworker)
chan.lnwatcher = self.lnwatcher
remote_sig = funding_created['signature']
chan.receive_new_commitment(remote_sig, [])
sig_64, _ = chan.sign_next_commitment()
self.send_message('funding_signed',
channel_id=channel_id,
signature=sig_64,
)
chan.set_state('OPENING')
chan.remote_commitment_to_be_revoked = chan.pending_commitment(REMOTE)
chan.config[REMOTE] = chan.config[REMOTE]._replace(ctn=0, current_per_commitment_point=payload['first_per_commitment_point'], next_per_commitment_point=None)
chan.config[LOCAL] = chan.config[LOCAL]._replace(ctn=0, current_commitment_signature=remote_sig)
self.lnworker.save_channel(chan)
self.lnwatcher.watch_channel(chan.get_funding_address(), chan.funding_outpoint.to_str())
self.lnworker.on_channels_updated()
while True:
try:
funding_tx = Transaction(await self.network.get_transaction(funding_txid))
except aiorpcx.jsonrpc.RPCError as e:
print("sleeping", str(e))
await asyncio.sleep(1)
else:
break
outp = funding_tx.outputs()[funding_idx]
redeem_script = funding_output_script(chan.config[REMOTE], chan.config[LOCAL])
funding_address = bitcoin.redeem_script_to_address('p2wsh', redeem_script)
if outp != TxOutput(bitcoin.TYPE_ADDRESS, funding_address, funding_sat):
chan.set_state('DISCONNECTED')
raise Exception('funding outpoint mismatch')
def validate_remote_reserve(self, payload_field: bytes, dust_limit: int, funding_sat: int) -> int:
remote_reserve_sat = int.from_bytes(payload_field, 'big')
if remote_reserve_sat < dust_limit:
raise Exception('protocol violation: reserve < dust_limit')
if remote_reserve_sat > funding_sat/100:
raise Exception(f'reserve too high: {remote_reserve_sat}, funding_sat: {funding_sat}')
return remote_reserve_sat
def on_channel_reestablish(self, payload):
chan_id = payload["channel_id"]
self.print_error("Received channel_reestablish", bh2u(chan_id))
chan = self.channels.get(chan_id)
if not chan:
self.print_error("Warning: received unknown channel_reestablish", bh2u(chan_id))
return
self.channel_reestablished[chan_id].set_result(payload)
@log_exceptions
async def reestablish_channel(self, chan: Channel):
await self.initialized.wait()
chan_id = chan.channel_id
if chan.get_state() != 'DISCONNECTED':
self.print_error('reestablish_channel was called but channel {} already in state {}'
.format(chan_id, chan.get_state()))
return
chan.set_state('REESTABLISHING')
self.network.trigger_callback('channel', chan)
self.send_message("channel_reestablish",
channel_id=chan_id,
next_local_commitment_number=chan.config[LOCAL].ctn+1,
next_remote_revocation_number=chan.config[REMOTE].ctn
)
channel_reestablish_msg = await self.channel_reestablished[chan_id]
chan.set_state('OPENING')
def try_to_get_remote_to_force_close_with_their_latest():
self.print_error("trying to get remote to force close", bh2u(chan_id))
self.send_message("channel_reestablish",
channel_id=chan_id,
next_local_commitment_number=0,
next_remote_revocation_number=0
)
# compare remote ctns
remote_ctn = int.from_bytes(channel_reestablish_msg["next_local_commitment_number"], 'big')
if remote_ctn != chan.config[REMOTE].ctn + 1:
self.print_error("expected remote ctn {}, got {}".format(chan.config[REMOTE].ctn + 1, remote_ctn))
# TODO iff their ctn is lower than ours, we should force close instead
try_to_get_remote_to_force_close_with_their_latest()
return
# compare local ctns
local_ctn = int.from_bytes(channel_reestablish_msg["next_remote_revocation_number"], 'big')
if local_ctn != chan.config[LOCAL].ctn:
if remote_ctn == chan.config[LOCAL].ctn + 1:
# A node:
# if next_remote_revocation_number is equal to the
# commitment number of the last revoke_and_ack
# the receiving node sent, AND the receiving node
# hasn't already received a closing_signed:
# MUST re-send the revoke_and_ack.
chan.config[LOCAL]=chan.config[LOCAL]._replace(
ctn=remote_ctn,
)
self.send_revoke_and_ack(chan)
else:
self.print_error("expected local ctn {}, got {}".format(chan.config[LOCAL].ctn, local_ctn))
# TODO iff their ctn is lower than ours, we should force close instead
try_to_get_remote_to_force_close_with_their_latest()
return
# compare per commitment points (needs data_protect option)
their_pcp = channel_reestablish_msg.get("my_current_per_commitment_point", None)
if their_pcp is not None:
our_pcp = chan.config[REMOTE].current_per_commitment_point
if our_pcp is None:
our_pcp = chan.config[REMOTE].next_per_commitment_point
if our_pcp != their_pcp:
self.print_error("Remote PCP mismatch: {} {}".format(bh2u(our_pcp), bh2u(their_pcp)))
# FIXME ...what now?
try_to_get_remote_to_force_close_with_their_latest()
return
if remote_ctn == chan.config[LOCAL].ctn+1 == 1 and chan.short_channel_id:
self.send_funding_locked(chan)
# checks done
if chan.config[LOCAL].funding_locked_received and chan.short_channel_id:
self.mark_open(chan)
self.network.trigger_callback('channel', chan)
def send_funding_locked(self, chan: Channel):
channel_id = chan.channel_id
per_commitment_secret_index = RevocationStore.START_INDEX - 1
per_commitment_point_second = secret_to_pubkey(int.from_bytes(
get_per_commitment_secret_from_seed(chan.config[LOCAL].per_commitment_secret_seed, per_commitment_secret_index), 'big'))
# note: if funding_locked was not yet received, we might send it multiple times
self.send_message("funding_locked", channel_id=channel_id, next_per_commitment_point=per_commitment_point_second)
if chan.config[LOCAL].funding_locked_received and chan.short_channel_id:
self.mark_open(chan)
def on_funding_locked(self, payload):
channel_id = payload['channel_id']
chan = self.channels.get(channel_id)
if not chan:
print(self.channels)
raise Exception("Got unknown funding_locked", channel_id)
if not chan.config[LOCAL].funding_locked_received:
our_next_point = chan.config[REMOTE].next_per_commitment_point
their_next_point = payload["next_per_commitment_point"]
new_remote_state = chan.config[REMOTE]._replace(next_per_commitment_point=their_next_point)
new_local_state = chan.config[LOCAL]._replace(funding_locked_received = True)
chan.config[REMOTE]=new_remote_state
chan.config[LOCAL]=new_local_state
self.lnworker.save_channel(chan)
if chan.short_channel_id:
self.mark_open(chan)
def on_network_update(self, chan: Channel, funding_tx_depth: int):
"""
Only called when the channel is OPEN.
Runs on the Network thread.
"""
if not chan.config[LOCAL].was_announced and funding_tx_depth >= 6:
# don't announce our channels
# FIXME should this be a field in chan.local_state maybe?
return
chan.config[LOCAL]=chan.config[LOCAL]._replace(was_announced=True)
coro = self.handle_announcements(chan)
self.lnworker.save_channel(chan)
asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop)
@log_exceptions
async def handle_announcements(self, chan):
h, local_node_sig, local_bitcoin_sig = self.send_announcement_signatures(chan)
announcement_signatures_msg = await self.announcement_signatures[chan.channel_id].get()
remote_node_sig = announcement_signatures_msg["node_signature"]
remote_bitcoin_sig = announcement_signatures_msg["bitcoin_signature"]
if not ecc.verify_signature(chan.config[REMOTE].multisig_key.pubkey, remote_bitcoin_sig, h):
raise Exception("bitcoin_sig invalid in announcement_signatures")
if not ecc.verify_signature(self.pubkey, remote_node_sig, h):
raise Exception("node_sig invalid in announcement_signatures")
node_sigs = [remote_node_sig, local_node_sig]
bitcoin_sigs = [remote_bitcoin_sig, local_bitcoin_sig]
bitcoin_keys = [chan.config[REMOTE].multisig_key.pubkey, chan.config[LOCAL].multisig_key.pubkey]
if self.node_ids[0] > self.node_ids[1]:
node_sigs.reverse()
bitcoin_sigs.reverse()
node_ids = list(reversed(self.node_ids))
bitcoin_keys.reverse()
else:
node_ids = self.node_ids
self.send_message("channel_announcement",
node_signatures_1=node_sigs[0],
node_signatures_2=node_sigs[1],
bitcoin_signature_1=bitcoin_sigs[0],
bitcoin_signature_2=bitcoin_sigs[1],
len=0,
#features not set (defaults to zeros)
chain_hash=constants.net.rev_genesis_bytes(),
short_channel_id=chan.short_channel_id,
node_id_1=node_ids[0],
node_id_2=node_ids[1],
bitcoin_key_1=bitcoin_keys[0],
bitcoin_key_2=bitcoin_keys[1]
)
print("SENT CHANNEL ANNOUNCEMENT")
def mark_open(self, chan: Channel):
assert chan.short_channel_id is not None
if chan.get_state() == "OPEN":
return
# NOTE: even closed channels will be temporarily marked "OPEN"
assert chan.config[LOCAL].funding_locked_received
chan.set_state("OPEN")
self.network.trigger_callback('channel', chan)
# add channel to database
bitcoin_keys = [chan.config[LOCAL].multisig_key.pubkey, chan.config[REMOTE].multisig_key.pubkey]
sorted_node_ids = list(sorted(self.node_ids))
if sorted_node_ids != self.node_ids:
node_ids = sorted_node_ids
bitcoin_keys.reverse()
else:
node_ids = self.node_ids
# note: we inject a channel announcement, and a channel update (for outgoing direction)
# This is atm needed for
# - finding routes
# - the ChanAnn is needed so that we can anchor to it a future ChanUpd
# that the remote sends, even if the channel was not announced
# (from BOLT-07: "MAY create a channel_update to communicate the channel
# parameters to the final node, even though the channel has not yet been announced")
self.channel_db.on_channel_announcement({"short_channel_id": chan.short_channel_id, "node_id_1": node_ids[0], "node_id_2": node_ids[1],
'chain_hash': constants.net.rev_genesis_bytes(), 'len': b'\x00\x00', 'features': b'',
'bitcoin_key_1': bitcoin_keys[0], 'bitcoin_key_2': bitcoin_keys[1]},
trusted=True)
# only inject outgoing direction:
if node_ids[0] == privkey_to_pubkey(self.privkey):
channel_flags = b'\x00'
else:
channel_flags = b'\x01'
now = int(time.time()).to_bytes(4, byteorder="big")
self.channel_db.on_channel_update({"short_channel_id": chan.short_channel_id, 'channel_flags': channel_flags, 'cltv_expiry_delta': b'\x90',
'htlc_minimum_msat': b'\x03\xe8', 'fee_base_msat': b'\x03\xe8', 'fee_proportional_millionths': b'\x01',
'chain_hash': constants.net.rev_genesis_bytes(), 'timestamp': now},
trusted=True)
# peer may have sent us a channel update for the incoming direction previously
# note: if we were offline when the 3rd conf happened, lnd will never send us this channel_update
# see https://github.com/lightningnetwork/lnd/issues/1347
#self.send_message("query_short_channel_ids", chain_hash=constants.net.rev_genesis_bytes(),
# len=9, encoded_short_ids=b'\x00'+chan.short_channel_id)
pending_channel_update = self.orphan_channel_updates.get(chan.short_channel_id)
if pending_channel_update:
self.channel_db.on_channel_update(pending_channel_update)
self.print_error("CHANNEL OPENING COMPLETED")
def send_announcement_signatures(self, chan: Channel):
bitcoin_keys = [chan.config[REMOTE].multisig_key.pubkey,
chan.config[LOCAL].multisig_key.pubkey]
sorted_node_ids = list(sorted(self.node_ids))
if sorted_node_ids != self.node_ids:
node_ids = sorted_node_ids
bitcoin_keys.reverse()
else:
node_ids = self.node_ids
chan_ann = encode_msg("channel_announcement",
len=0,
#features not set (defaults to zeros)
chain_hash=constants.net.rev_genesis_bytes(),
short_channel_id=chan.short_channel_id,
node_id_1=node_ids[0],
node_id_2=node_ids[1],
bitcoin_key_1=bitcoin_keys[0],
bitcoin_key_2=bitcoin_keys[1]
)
to_hash = chan_ann[256+2:]
h = sha256d(to_hash)
bitcoin_signature = ecc.ECPrivkey(chan.config[LOCAL].multisig_key.privkey).sign(h, sig_string_from_r_and_s, get_r_and_s_from_sig_string)
node_signature = ecc.ECPrivkey(self.privkey).sign(h, sig_string_from_r_and_s, get_r_and_s_from_sig_string)
self.send_message("announcement_signatures",
channel_id=chan.channel_id,
short_channel_id=chan.short_channel_id,
node_signature=node_signature,
bitcoin_signature=bitcoin_signature
)
return h, node_signature, bitcoin_signature
def on_update_fail_htlc(self, payload):
channel_id = payload["channel_id"]
htlc_id = int.from_bytes(payload["id"], "big")
key = (channel_id, htlc_id)
try:
route = self.attempted_route[key]
except KeyError:
# the remote might try to fail an htlc after we restarted...
# attempted_route is not persisted, so we will get here then
self.print_error("UPDATE_FAIL_HTLC. cannot decode! attempted route is MISSING. {}".format(key))
else:
try:
self._handle_error_code_from_failed_htlc(payload["reason"], route, channel_id, htlc_id)
except Exception:
# exceptions are suppressed as failing to handle an error code
# should not block us from removing the htlc
traceback.print_exc(file=sys.stderr)
# process update_fail_htlc on channel
chan = self.channels[channel_id]
chan.receive_fail_htlc(htlc_id)
local_ctn = chan.get_current_ctn(LOCAL)
asyncio.ensure_future(self._on_update_fail_htlc(chan, htlc_id, local_ctn))
@log_exceptions
async def _on_update_fail_htlc(self, chan, htlc_id, local_ctn):
await self.await_local(chan, local_ctn)
self.network.trigger_callback('ln_message', self.lnworker, 'Payment failed', htlc_id)
def _handle_error_code_from_failed_htlc(self, error_reason, route: List['RouteEdge'], channel_id, htlc_id):
chan = self.channels[channel_id]
failure_msg, sender_idx = decode_onion_error(error_reason,
[x.node_id for x in route],
chan.onion_keys[htlc_id])
code, data = failure_msg.code, 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,
OnionFailureCode.AMOUNT_BELOW_MINIMUM: 10,
OnionFailureCode.FEE_INSUFFICIENT: 10,
OnionFailureCode.INCORRECT_CLTV_EXPIRY: 6,
OnionFailureCode.EXPIRY_TOO_SOON: 2,
OnionFailureCode.CHANNEL_DISABLED: 4,
}
offset = failure_codes.get(code)
if offset:
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:
# blacklist channel after reporter node
# TODO this should depend on the error (even more granularity)
# also, we need finer blacklisting (directed edges; nodes)
try:
short_chan_id = route[sender_idx + 1].short_channel_id
except IndexError:
self.print_error("payment destination reported error")
else:
self.network.path_finder.blacklist.add(short_chan_id)
def maybe_send_commitment(self, chan: Channel):
ctn_to_sign = chan.get_current_ctn(REMOTE) + 1
# if there are no changes, we will not (and must not) send a new commitment
pending, current = chan.hm.pending_htlcs(REMOTE), chan.hm.current_htlcs(REMOTE)
if (pending == current
and chan.pending_feerate(REMOTE) == chan.constraints.feerate) \
or ctn_to_sign == self.sent_commitment_for_ctn_last[chan]:
return
self.print_error(f'send_commitment. old number htlcs: {len(current)}, new number htlcs: {len(pending)}')
sig_64, htlc_sigs = chan.sign_next_commitment()
self.send_message("commitment_signed", channel_id=chan.channel_id, signature=sig_64, num_htlcs=len(htlc_sigs), htlc_signature=b"".join(htlc_sigs))
self.sent_commitment_for_ctn_last[chan] = ctn_to_sign
async def await_remote(self, chan: Channel, ctn: int):
self.maybe_send_commitment(chan)
while chan.get_current_ctn(REMOTE) <= ctn:
await self._remote_changed_events[chan.channel_id].wait()
async def await_local(self, chan: Channel, ctn: int):
self.maybe_send_commitment(chan)
while chan.get_current_ctn(LOCAL) <= ctn:
await self._local_changed_events[chan.channel_id].wait()
async def pay(self, route: List['RouteEdge'], chan: Channel, amount_msat: int,
payment_hash: bytes, min_final_cltv_expiry: int) -> UpdateAddHtlc:
assert chan.get_state() == "OPEN", chan.get_state()
assert amount_msat > 0, "amount_msat is not greater zero"
# create onion packet
final_cltv = self.network.get_local_height() + min_final_cltv_expiry
hops_data, amount_msat, cltv = calc_hops_data_for_payment(route, amount_msat, final_cltv)
assert final_cltv <= cltv, (final_cltv, cltv)
secret_key = os.urandom(32)
onion = new_onion_packet([x.node_id for x in route], secret_key, hops_data, associated_data=payment_hash)
# create htlc
htlc = UpdateAddHtlc(amount_msat=amount_msat, payment_hash=payment_hash, cltv_expiry=cltv)
htlc = chan.add_htlc(htlc)
remote_ctn = chan.get_current_ctn(REMOTE)
chan.onion_keys[htlc.htlc_id] = secret_key
self.attempted_route[(chan.channel_id, htlc.htlc_id)] = route
self.print_error(f"starting payment. route: {route}")
self.send_message("update_add_htlc",
channel_id=chan.channel_id,
id=htlc.htlc_id,
cltv_expiry=htlc.cltv_expiry,
amount_msat=htlc.amount_msat,
payment_hash=htlc.payment_hash,
onion_routing_packet=onion.to_bytes())
await self.await_remote(chan, remote_ctn)
return htlc
def send_revoke_and_ack(self, chan: Channel):
rev, _ = chan.revoke_current_commitment()
self.lnworker.save_channel(chan)
self._local_changed_events[chan.channel_id].set()
self._local_changed_events[chan.channel_id].clear()
self.send_message("revoke_and_ack",
channel_id=chan.channel_id,
per_commitment_secret=rev.per_commitment_secret,
next_per_commitment_point=rev.next_per_commitment_point)
self.maybe_send_commitment(chan)
def on_commitment_signed(self, payload):
self.print_error("on_commitment_signed")
channel_id = payload['channel_id']
chan = self.channels[channel_id]
ctn_to_recv = chan.get_current_ctn(LOCAL) + 1
# make sure there were changes to the ctx, otherwise the remote peer is misbehaving
if (chan.hm.pending_htlcs(LOCAL) == chan.hm.current_htlcs(LOCAL)
and chan.pending_feerate(LOCAL) == chan.constraints.feerate) \
or ctn_to_recv == self.recv_commitment_for_ctn_last[chan]:
raise RemoteMisbehaving('received commitment_signed without any change')
self.recv_commitment_for_ctn_last[chan] = ctn_to_recv
data = payload["htlc_signature"]
htlc_sigs = [data[i:i+64] for i in range(0, len(data), 64)]
chan.receive_new_commitment(payload["signature"], htlc_sigs)
self.send_revoke_and_ack(chan)
def on_update_fulfill_htlc(self, update_fulfill_htlc_msg):
self.print_error("update_fulfill")
chan = self.channels[update_fulfill_htlc_msg["channel_id"]]
preimage = update_fulfill_htlc_msg["payment_preimage"]
htlc_id = int.from_bytes(update_fulfill_htlc_msg["id"], "big")
chan.receive_htlc_settle(preimage, htlc_id)
local_ctn = chan.get_current_ctn(LOCAL)
asyncio.ensure_future(self._on_update_fulfill_htlc(chan, htlc_id, preimage, local_ctn))
@log_exceptions
async def _on_update_fulfill_htlc(self, chan, htlc_id, preimage, local_ctn):
await self.await_local(chan, local_ctn)
self.network.trigger_callback('ln_message', self.lnworker, 'Payment sent', htlc_id)
self.payment_preimages[sha256(preimage)].put_nowait(preimage)
def on_update_fail_malformed_htlc(self, payload):
self.print_error("error", payload["data"].decode("ascii"))
def on_update_add_htlc(self, payload):
# no onion routing for the moment: we assume we are the end node
self.print_error('on_update_add_htlc')
# check if this in our list of requests
payment_hash = payload["payment_hash"]
channel_id = payload['channel_id']
htlc_id = int.from_bytes(payload["id"], 'big')
cltv_expiry = int.from_bytes(payload["cltv_expiry"], 'big')
amount_msat_htlc = int.from_bytes(payload["amount_msat"], 'big')
onion_packet = OnionPacket.from_bytes(payload["onion_routing_packet"])
processed_onion = process_onion_packet(onion_packet, associated_data=payment_hash, our_onion_private_key=self.privkey)
chan = self.channels[channel_id]
assert chan.get_state() == "OPEN"
assert htlc_id == chan.config[REMOTE].next_htlc_id, (htlc_id, chan.config[REMOTE].next_htlc_id) # TODO fail channel instead
if cltv_expiry >= 500_000_000:
pass # TODO fail the channel
# add htlc
htlc = UpdateAddHtlc(amount_msat=amount_msat_htlc, payment_hash=payment_hash, cltv_expiry=cltv_expiry)
htlc = chan.receive_htlc(htlc)
local_ctn = chan.get_current_ctn(LOCAL)
remote_ctn = chan.get_current_ctn(REMOTE)
if processed_onion.are_we_final:
asyncio.ensure_future(self._maybe_fulfill_htlc(chan=chan,
htlc=htlc,
local_ctn=local_ctn,
remote_ctn=remote_ctn,
onion_packet=onion_packet,
processed_onion=processed_onion))
else:
asyncio.ensure_future(self._maybe_forward_htlc(chan=chan,
htlc=htlc,
local_ctn=local_ctn,
remote_ctn=remote_ctn,
onion_packet=onion_packet,
processed_onion=processed_onion))
@log_exceptions
async def _maybe_forward_htlc(self, chan: Channel, htlc: UpdateAddHtlc, *, local_ctn: int, remote_ctn: int,
onion_packet: OnionPacket, processed_onion: ProcessedOnionPacket):
await self.await_local(chan, local_ctn)
await self.await_remote(chan, remote_ctn)
# Forward HTLC
# FIXME: this is not robust to us going offline before payment is fulfilled
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.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 = UpdateAddHtlc(amount_msat=next_amount_msat_htlc, payment_hash=htlc.payment_hash, cltv_expiry=next_cltv_expiry)
next_htlc = next_chan.add_htlc(next_htlc)
next_remote_ctn = next_chan.get_current_ctn(REMOTE)
next_peer.send_message(
"update_add_htlc",
channel_id=next_chan.channel_id,
id=next_htlc.htlc_id,
cltv_expiry=dph.outgoing_cltv_value,
amount_msat=dph.amt_to_forward,
payment_hash=next_htlc.payment_hash,
onion_routing_packet=processed_onion.next_packet.to_bytes()
)
await next_peer.await_remote(next_chan, next_remote_ctn)
# wait until we get paid
preimage = await next_peer.payment_preimages[next_htlc.payment_hash].get()
# fulfill the original htlc
await self._fulfill_htlc(chan, htlc.htlc_id, preimage)
self.print_error("htlc forwarded successfully")
@log_exceptions
async def _maybe_fulfill_htlc(self, chan: Channel, htlc: UpdateAddHtlc, *, local_ctn: int, remote_ctn: int,
onion_packet: OnionPacket, processed_onion: ProcessedOnionPacket):
await self.await_local(chan, local_ctn)
await self.await_remote(chan, remote_ctn)
try:
invoice = self.lnworker.get_invoice(htlc.payment_hash)
preimage = self.lnworker.get_preimage(htlc.payment_hash)
except UnknownPaymentHash:
reason = OnionRoutingFailureMessage(code=OnionFailureCode.UNKNOWN_PAYMENT_HASH, data=b'')
await self.fail_htlc(chan, htlc.htlc_id, onion_packet, reason)
return
expected_received_msat = int(invoice.amount * bitcoin.COIN * 1000) if invoice.amount is not None else None
if expected_received_msat is not None and \
(htlc.amount_msat < expected_received_msat or htlc.amount_msat > 2 * expected_received_msat):
reason = OnionRoutingFailureMessage(code=OnionFailureCode.INCORRECT_PAYMENT_AMOUNT, data=b'')
await self.fail_htlc(chan, htlc.htlc_id, onion_packet, reason)
return
local_height = self.network.get_local_height()
if local_height + MIN_FINAL_CLTV_EXPIRY_ACCEPTED > htlc.cltv_expiry:
reason = OnionRoutingFailureMessage(code=OnionFailureCode.FINAL_EXPIRY_TOO_SOON, data=b'')
await self.fail_htlc(chan, htlc.htlc_id, onion_packet, reason)
return
cltv_from_onion = int.from_bytes(processed_onion.hop_data.per_hop.outgoing_cltv_value, byteorder="big")
if cltv_from_onion != htlc.cltv_expiry:
reason = OnionRoutingFailureMessage(code=OnionFailureCode.FINAL_INCORRECT_CLTV_EXPIRY,
data=htlc.cltv_expiry.to_bytes(4, byteorder="big"))
await self.fail_htlc(chan, htlc.htlc_id, onion_packet, reason)
return
amount_from_onion = int.from_bytes(processed_onion.hop_data.per_hop.amt_to_forward, byteorder="big")
if amount_from_onion > htlc.amount_msat:
reason = OnionRoutingFailureMessage(code=OnionFailureCode.FINAL_INCORRECT_HTLC_AMOUNT,
data=htlc.amount_msat.to_bytes(8, byteorder="big"))
await self.fail_htlc(chan, htlc.htlc_id, onion_packet, reason)
return
self.network.trigger_callback('htlc_added', htlc, invoice, RECEIVED)
if self.network.config.debug_lightning_do_not_settle:
return
await self._fulfill_htlc(chan, htlc.htlc_id, preimage)
async def _fulfill_htlc(self, chan: Channel, htlc_id: int, preimage: bytes):
chan.settle_htlc(preimage, htlc_id)
remote_ctn = chan.get_current_ctn(REMOTE)
self.send_message("update_fulfill_htlc",
channel_id=chan.channel_id,
id=htlc_id,
payment_preimage=preimage)
await self.await_remote(chan, remote_ctn)
self.network.trigger_callback('ln_message', self.lnworker, 'Payment received', htlc_id)
async def fail_htlc(self, chan: Channel, htlc_id: int, onion_packet: OnionPacket,
reason: OnionRoutingFailureMessage):
self.print_error(f"failing received htlc {(bh2u(chan.channel_id), htlc_id)}. reason: {reason}")
chan.fail_htlc(htlc_id)
remote_ctn = chan.get_current_ctn(REMOTE)
error_packet = construct_onion_error(reason, onion_packet, our_onion_private_key=self.privkey)
self.send_message("update_fail_htlc",
channel_id=chan.channel_id,
id=htlc_id,
len=len(error_packet),
reason=error_packet)
await self.await_remote(chan, remote_ctn)
def on_revoke_and_ack(self, payload):
self.print_error("on_revoke_and_ack")
channel_id = payload["channel_id"]
chan = self.channels[channel_id]
chan.receive_revocation(RevokeAndAck(payload["per_commitment_secret"], payload["next_per_commitment_point"]))
self._remote_changed_events[chan.channel_id].set()
self._remote_changed_events[chan.channel_id].clear()
self.lnworker.save_channel(chan)
def on_update_fee(self, payload):
channel_id = payload["channel_id"]
feerate =int.from_bytes(payload["feerate_per_kw"], "big")
chan = self.channels[channel_id]
chan.update_fee(feerate, False)
async def bitcoin_fee_update(self, chan: Channel):
"""
called when our fee estimates change
"""
if not chan.constraints.is_initiator:
# TODO force close if initiator does not update_fee enough
return
feerate_per_kw = self.lnworker.current_feerate_per_kw()
chan_fee = chan.pending_feerate(REMOTE)
self.print_error("current pending feerate", chan_fee)
self.print_error("new feerate", feerate_per_kw)
if feerate_per_kw < chan_fee / 2:
self.print_error("FEES HAVE FALLEN")
elif feerate_per_kw > chan_fee * 2:
self.print_error("FEES HAVE RISEN")
else:
return
chan.update_fee(feerate_per_kw, True)
remote_ctn = chan.get_current_ctn(REMOTE)
self.send_message("update_fee",
channel_id=chan.channel_id,
feerate_per_kw=feerate_per_kw)
await self.await_remote(chan, remote_ctn)
def on_closing_signed(self, payload):
chan_id = payload["channel_id"]
if chan_id not in self.closing_signed: raise Exception("Got unknown closing_signed")
self.closing_signed[chan_id].put_nowait(payload)
@log_exceptions
async def close_channel(self, chan_id: bytes):
chan = self.channels[chan_id]
self.shutdown_received[chan_id] = asyncio.Future()
self.send_shutdown(chan)
payload = await self.shutdown_received[chan_id]
txid = await self._shutdown(chan, payload, True)
self.print_error('Channel closed', txid)
return txid
@log_exceptions
async def on_shutdown(self, payload):
# length of scripts allowed in BOLT-02
if int.from_bytes(payload['len'], 'big') not in (3+20+2, 2+20+1, 2+20, 2+32):
raise Exception('scriptpubkey length in received shutdown message invalid: ' + str(payload['len']))
chan_id = payload['channel_id']
if chan_id in self.shutdown_received:
self.shutdown_received[chan_id].set_result(payload)
else:
chan = self.channels[chan_id]
self.send_shutdown(chan)
txid = await self._shutdown(chan, payload, False)
self.print_error('Channel closed by remote peer', txid)
def send_shutdown(self, chan: Channel):
scriptpubkey = bfh(bitcoin.address_to_script(chan.sweep_address))
self.send_message('shutdown', channel_id=chan.channel_id, len=len(scriptpubkey), scriptpubkey=scriptpubkey)
@log_exceptions
async def _shutdown(self, chan: Channel, payload, is_local):
# set state so that we stop accepting HTLCs
chan.set_state('CLOSING')
while len(chan.hm.htlcs_by_direction(LOCAL, RECEIVED)) > 0:
self.print_error('waiting for htlcs to settle...')
await asyncio.sleep(1)
our_fee = chan.pending_local_fee()
scriptpubkey = bfh(bitcoin.address_to_script(chan.sweep_address))
# negociate fee
while True:
our_sig, closing_tx = chan.make_closing_tx(scriptpubkey, payload['scriptpubkey'], fee_sat=our_fee)
self.send_message('closing_signed', channel_id=chan.channel_id, fee_satoshis=our_fee, signature=our_sig)
cs_payload = await asyncio.wait_for(self.closing_signed[chan.channel_id].get(), 1)
their_fee = int.from_bytes(cs_payload['fee_satoshis'], 'big')
their_sig = cs_payload['signature']
if our_fee == their_fee:
break
# TODO: negociate better
our_fee = their_fee
# index of our_sig
i = bool(chan.get_local_index())
if not is_local: i = not i
# add signatures
closing_tx.add_signature_to_txin(0, int(i), bh2u(der_sig_from_sig_string(our_sig) + b'\x01'))
closing_tx.add_signature_to_txin(0, int(not i), bh2u(der_sig_from_sig_string(their_sig) + b'\x01'))
# broadcast
await self.network.broadcast_transaction(closing_tx)
return closing_tx.txid()