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1020 lines
41 KiB
1020 lines
41 KiB
#!/usr/bin/env python3
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"""
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Lightning network interface for Electrum
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Derived from https://gist.github.com/AdamISZ/046d05c156aaeb56cc897f85eecb3eb8
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"""
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from ecdsa.util import sigdecode_der, sigencode_string_canonize
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from ecdsa import VerifyingKey
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from ecdsa.curves import SECP256k1
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import subprocess
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import queue
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import traceback
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import itertools
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import json
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from collections import OrderedDict, defaultdict
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import asyncio
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import sys
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import os
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import time
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import binascii
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import hashlib
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import hmac
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import cryptography.hazmat.primitives.ciphers.aead as AEAD
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from .bitcoin import (public_key_from_private_key, ser_to_point, point_to_ser,
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string_to_number, deserialize_privkey, EC_KEY, rev_hex, int_to_hex,
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push_script, script_num_to_hex, add_data_to_script,
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add_number_to_script, var_int, witness_push)
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from . import bitcoin
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from . import constants
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from . import transaction
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from .util import PrintError, bh2u, print_error, bfh, profiler
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from .transaction import opcodes, Transaction
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# hardcoded nodes
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node_list = [
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('ecdsa.net', '9735', '038370f0e7a03eded3e1d41dc081084a87f0afa1c5b22090b4f3abb391eb15d8ff'),
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('77.58.162.148', '9735', '022bb78ab9df617aeaaf37f6644609abb7295fad0c20327bccd41f8d69173ccb49')
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]
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class LightningError(Exception):
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pass
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message_types = {}
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def handlesingle(x, ma):
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"""
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Evaluate a term of the simple language used
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to specify lightning message field lengths.
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If `x` is an integer, it is returned as is,
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otherwise it is treated as a variable and
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looked up in `ma`.
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It the value in `ma` was no integer, it is
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assumed big-endian bytes and decoded.
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Returns int
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"""
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try:
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x = int(x)
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except ValueError:
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x = ma[x]
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try:
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x = int(x)
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except ValueError:
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x = int.from_bytes(x, byteorder="big")
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return x
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def calcexp(exp, ma):
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"""
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Evaluate simple mathematical expression given
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in `exp` with variables assigned in the dict `ma`
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Returns int
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"""
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exp = str(exp)
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assert "*" not in exp
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return sum(handlesingle(x, ma) for x in exp.split("+"))
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def make_handler(k, v):
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"""
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Generate a message handler function (taking bytes)
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for message type `k` with specification `v`
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Check lib/lightning.json, `k` could be 'init',
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and `v` could be
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{ type: 16, payload: { 'gflen': ..., ... }, ... }
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Returns function taking bytes
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"""
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def handler(data):
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nonlocal k, v
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ma = {}
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pos = 0
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for fieldname in v["payload"]:
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poslenMap = v["payload"][fieldname]
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if "feature" in poslenMap: continue
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#print(poslenMap["position"], ma)
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assert pos == calcexp(poslenMap["position"], ma)
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length = poslenMap["length"]
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length = calcexp(length, ma)
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ma[fieldname] = data[pos:pos+length]
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pos += length
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assert pos == len(data), (k, pos, len(data))
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return k, ma
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return handler
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path = os.path.join(os.path.dirname(__file__), 'lightning.json')
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with open(path) as f:
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structured = json.loads(f.read(), object_pairs_hook=OrderedDict)
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for k in structured:
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v = structured[k]
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# these message types are skipped since their types collide
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# (for example with pong, which also uses type=19)
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# we don't need them yet
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if k in ["final_incorrect_cltv_expiry", "final_incorrect_htlc_amount"]:
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continue
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if len(v["payload"]) == 0:
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continue
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try:
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num = int(v["type"])
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except ValueError:
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#print("skipping", k)
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continue
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byts = num.to_bytes(byteorder="big",length=2)
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assert byts not in message_types, (byts, message_types[byts].__name__, k)
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names = [x.__name__ for x in message_types.values()]
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assert k + "_handler" not in names, (k, names)
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message_types[byts] = make_handler(k, v)
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message_types[byts].__name__ = k + "_handler"
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assert message_types[b"\x00\x10"].__name__ == "init_handler"
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def decode_msg(data):
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"""
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Decode Lightning message by reading the first
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two bytes to determine message type.
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Returns message type string and parsed message contents dict
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"""
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typ = data[:2]
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k, parsed = message_types[typ](data[2:])
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return k, parsed
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def gen_msg(msg_type, **kwargs):
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"""
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Encode kwargs into a Lightning message (bytes)
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of the type given in the msg_type string
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"""
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typ = structured[msg_type]
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data = int(typ["type"]).to_bytes(byteorder="big", length=2)
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lengths = {}
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for k in typ["payload"]:
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poslenMap = typ["payload"][k]
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if "feature" in poslenMap: continue
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leng = calcexp(poslenMap["length"], lengths)
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try:
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clone = dict(lengths)
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clone.update(kwargs)
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leng = calcexp(poslenMap["length"], clone)
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except KeyError:
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pass
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try:
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param = kwargs[k]
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except KeyError:
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param = 0
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try:
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if not isinstance(param, bytes):
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assert isinstance(param, int), "field {} is neither bytes or int".format(k)
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param = param.to_bytes(length=leng, byteorder="big")
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except ValueError:
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raise Exception("{} does not fit in {} bytes".format(k, leng))
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lengths[k] = len(param)
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if lengths[k] != leng:
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raise Exception("field {} is {} bytes long, should be {} bytes long".format(k, lengths[k], leng))
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data += param
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return data
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def encode(n, s):
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"""Return a bytestring version of the integer
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value n, with a string length of s
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"""
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return n.to_bytes(length=s, byteorder="big")
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def H256(data):
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return hashlib.sha256(data).digest()
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class HandshakeState(object):
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prologue = b"lightning"
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protocol_name = b"Noise_XK_secp256k1_ChaChaPoly_SHA256"
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handshake_version = b"\x00"
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def __init__(self, responder_pub):
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self.responder_pub = responder_pub
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self.h = H256(self.protocol_name)
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self.ck = self.h
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self.update(self.prologue)
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self.update(self.responder_pub)
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def update(self, data):
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self.h = H256(self.h + data)
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return self.h
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def get_nonce_bytes(n):
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"""BOLT 8 requires the nonce to be 12 bytes, 4 bytes leading
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zeroes and 8 bytes little endian encoded 64 bit integer.
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"""
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nb = b"\x00"*4
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#Encode the integer as an 8 byte byte-string
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nb2 = encode(n, 8)
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nb2 = bytearray(nb2)
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#Little-endian is required here
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nb2.reverse()
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return nb + nb2
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def aead_encrypt(k, nonce, associated_data, data):
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nonce_bytes = get_nonce_bytes(nonce)
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a = AEAD.ChaCha20Poly1305(k)
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return a.encrypt(nonce_bytes, data, associated_data)
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def aead_decrypt(k, nonce, associated_data, data):
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nonce_bytes = get_nonce_bytes(nonce)
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a = AEAD.ChaCha20Poly1305(k)
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#raises InvalidTag exception if it's not valid
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return a.decrypt(nonce_bytes, data, associated_data)
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def get_bolt8_hkdf(salt, ikm):
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"""RFC5869 HKDF instantiated in the specific form
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used in Lightning BOLT 8:
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Extract and expand to 64 bytes using HMAC-SHA256,
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with info field set to a zero length string as per BOLT8
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Return as two 32 byte fields.
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"""
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#Extract
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prk = hmac.new(salt, msg=ikm, digestmod=hashlib.sha256).digest()
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assert len(prk) == 32
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#Expand
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info = b""
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T0 = b""
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T1 = hmac.new(prk, T0 + info + b"\x01", digestmod=hashlib.sha256).digest()
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T2 = hmac.new(prk, T1 + info + b"\x02", digestmod=hashlib.sha256).digest()
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assert len(T1 + T2) == 64
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return T1, T2
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def get_ecdh(priv, pub):
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s = string_to_number(priv)
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pk = ser_to_point(pub)
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pt = point_to_ser(pk * s)
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return H256(pt)
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def act1_initiator_message(hs, my_privkey):
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#Get a new ephemeral key
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epriv, epub = create_ephemeral_key(my_privkey)
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hs.update(epub)
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ss = get_ecdh(epriv, hs.responder_pub)
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ck2, temp_k1 = get_bolt8_hkdf(hs.ck, ss)
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hs.ck = ck2
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c = aead_encrypt(temp_k1, 0, hs.h, b"")
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#for next step if we do it
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hs.update(c)
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msg = hs.handshake_version + epub + c
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assert len(msg) == 50
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return msg
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def privkey_to_pubkey(priv):
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pub = public_key_from_private_key(priv[:32], True)
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return bytes.fromhex(pub)
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def create_ephemeral_key(privkey):
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pub = privkey_to_pubkey(privkey)
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return (privkey[:32], pub)
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def get_unused_keys():
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xprv, xpub = bitcoin.bip32_root(b"testseed", "p2wpkh")
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for i in itertools.count():
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childxprv, childxpub = bitcoin.bip32_private_derivation(xprv, "m/", "m/42/"+str(i))
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_, _, _, _, child_c, child_cK = bitcoin.deserialize_xpub(childxpub)
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_, _, _, _, _, k = bitcoin.deserialize_xprv(childxprv)
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assert len(k) == 32
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yield child_cK, k
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def aiosafe(f):
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async def f2(*args, **kwargs):
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try:
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return await f(*args, **kwargs)
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except:
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# if the loop isn't stopped
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# run_forever in network.py would not return,
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# the asyncioThread would not die,
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# and we would block on shutdown
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asyncio.get_event_loop().stop()
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traceback.print_exc()
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return f2
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def get_obscured_ctn(ctn, local, remote):
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mask = int.from_bytes(H256(local + remote)[-6:], byteorder="big")
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return ctn ^ mask
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def secret_to_pubkey(secret):
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return point_to_ser(SECP256k1.generator * secret)
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def derive_pubkey(basepoint, per_commitment_point):
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p = ser_to_point(basepoint) + SECP256k1.generator * bitcoin.string_to_number(bitcoin.sha256(per_commitment_point + basepoint))
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return point_to_ser(p)
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def derive_privkey(secret, per_commitment_point):
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basepoint = point_to_ser(SECP256k1.generator * secret)
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return secret + bitcoin.string_to_number(bitcoin.sha256(per_commitment_point + basepoint))
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def derive_blinded_pubkey(basepoint, per_commitment_point):
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k1 = ser_to_point(basepoint) * bitcoin.string_to_number(bitcoin.sha256(basepoint + per_commitment_point))
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k2 = ser_to_point(per_commitment_point) * bitcoin.string_to_number(bitcoin.sha256(per_commitment_point + basepoint))
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return point_to_ser(k1 + k2)
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def get_per_commitment_secret_from_seed(seed: bytes, i: int, bits: int = 47) -> bytes:
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"""Generate per commitment secret."""
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per_commitment_secret = bytearray(seed)
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for bitindex in range(bits, -1, -1):
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mask = 1 << bitindex
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if i & mask:
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per_commitment_secret[bitindex // 8] ^= 1 << (bitindex % 8)
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per_commitment_secret = bytearray(bitcoin.sha256(per_commitment_secret))
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return bytes(per_commitment_secret)
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def overall_weight(num_htlc):
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return 500 + 172 * num_htlc + 224
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HTLC_TIMEOUT_WEIGHT = 663
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HTLC_SUCCESS_WEIGHT = 703
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def make_htlc_tx_output(amount_msat, local_feerate, revocationpubkey, local_delayedpubkey, success):
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assert type(amount_msat) is int
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assert type(local_feerate) is int
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assert type(revocationpubkey) is bytes
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assert type(local_delayedpubkey) is bytes
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script = bytes([opcodes.OP_IF]) \
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+ bfh(push_script(bh2u(revocationpubkey))) \
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+ bytes([opcodes.OP_ELSE]) \
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+ bitcoin.add_number_to_script(144) \
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+ bytes([opcodes.OP_CSV, opcodes.OP_DROP]) \
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+ bfh(push_script(bh2u(local_delayedpubkey))) \
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+ bytes([opcodes.OP_ENDIF, opcodes.OP_CHECKSIG])
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p2wsh = bitcoin.redeem_script_to_address('p2wsh', bh2u(script))
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weight = HTLC_SUCCESS_WEIGHT if success else HTLC_TIMEOUT_WEIGHT
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fee = local_feerate * weight
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output = (bitcoin.TYPE_ADDRESS, p2wsh, amount_msat // 1000 - fee)
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return output
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def make_htlc_tx_witness(remotehtlcsig, localhtlcsig, payment_preimage, witness_script):
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assert type(remotehtlcsig) is bytes
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assert type(localhtlcsig) is bytes
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assert type(payment_preimage) is bytes
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assert type(witness_script) is bytes
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return bfh(var_int(5) + '00' + ''.join([witness_push(x) for x in [bh2u(remotehtlcsig), bh2u(localhtlcsig), bh2u(payment_preimage), bh2u(witness_script)]]))
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def make_htlc_tx_inputs(htlc_output_txid, htlc_output_index, revocationpubkey, local_delayedpubkey, amount_msat, witness, pubkeys, sigs):
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assert type(htlc_output_txid) is str
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assert type(htlc_output_index) is int
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assert type(revocationpubkey) is bytes
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assert type(local_delayedpubkey) is bytes
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assert type(amount_msat) is int
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assert type(witness) is bytes
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c_inputs = [{
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'scriptSig': '',
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'type': 'p2wsh',
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'x_pubkeys': [bh2u(x) for x in pubkeys],
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'signatures': sigs,
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'num_sig': 2,
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'prevout_n': htlc_output_index,
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'prevout_hash': htlc_output_txid,
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'value': amount_msat // 1000,
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'coinbase': False,
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'sequence': 0x0,
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'witness': bh2u(witness)
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}]
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return c_inputs
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def make_htlc_tx(cltv_timeout, inputs, output):
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assert type(cltv_timeout) is int
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c_outputs = [output]
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tx = Transaction.from_io(inputs, c_outputs, locktime=cltv_timeout, version=2)
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tx.BIP_LI01_sort()
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return tx
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def make_offered_htlc(revocation_pubkey, remote_htlcpubkey, local_htlcpubkey, payment_preimage):
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assert type(revocation_pubkey) is bytes
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assert type(remote_htlcpubkey) is bytes
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assert type(local_htlcpubkey) is bytes
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assert type(payment_preimage) is bytes
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payment_hash = bitcoin.sha256(payment_preimage)
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return bytes([opcodes.OP_DUP, opcodes.OP_HASH160]) + bfh(push_script(bh2u(bitcoin.hash_160(revocation_pubkey))))\
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+ bytes([opcodes.OP_EQUAL, opcodes.OP_IF, opcodes.OP_CHECKSIG, opcodes.OP_ELSE]) \
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+ bfh(push_script(bh2u(remote_htlcpubkey)))\
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+ bytes([opcodes.OP_SWAP, opcodes.OP_SIZE]) + bitcoin.add_number_to_script(32) + bytes([opcodes.OP_EQUAL, opcodes.OP_NOTIF, opcodes.OP_DROP])\
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+ bitcoin.add_number_to_script(2) + bytes([opcodes.OP_SWAP]) + bfh(push_script(bh2u(local_htlcpubkey))) + bitcoin.add_number_to_script(2)\
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+ bytes([opcodes.OP_CHECKMULTISIG, opcodes.OP_ELSE, opcodes.OP_HASH160])\
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+ bfh(push_script(bh2u(bitcoin.ripemd(payment_hash)))) + bytes([opcodes.OP_EQUALVERIFY, opcodes.OP_CHECKSIG, opcodes.OP_ENDIF, opcodes.OP_ENDIF])
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|
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def make_received_htlc(revocation_pubkey, remote_htlcpubkey, local_htlcpubkey, payment_preimage, cltv_expiry):
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for i in [revocation_pubkey, remote_htlcpubkey, local_htlcpubkey, payment_preimage]:
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assert type(i) is bytes
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assert type(cltv_expiry) is int
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payment_hash = bitcoin.sha256(payment_preimage)
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return bytes([opcodes.OP_DUP, opcodes.OP_HASH160]) \
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+ bfh(push_script(bh2u(bitcoin.hash_160(revocation_pubkey)))) \
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+ bytes([opcodes.OP_EQUAL, opcodes.OP_IF, opcodes.OP_CHECKSIG, opcodes.OP_ELSE]) \
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+ bfh(push_script(bh2u(remote_htlcpubkey))) \
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+ bytes([opcodes.OP_SWAP, opcodes.OP_SIZE]) \
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+ bitcoin.add_number_to_script(32) \
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+ bytes([opcodes.OP_EQUAL, opcodes.OP_IF, opcodes.OP_HASH160]) \
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+ bfh(push_script(bh2u(bitcoin.ripemd(payment_hash)))) \
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+ bytes([opcodes.OP_EQUALVERIFY]) \
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+ bitcoin.add_number_to_script(2) \
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+ bytes([opcodes.OP_SWAP]) \
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+ bfh(push_script(bh2u(local_htlcpubkey))) \
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+ bitcoin.add_number_to_script(2) \
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+ bytes([opcodes.OP_CHECKMULTISIG, opcodes.OP_ELSE, opcodes.OP_DROP]) \
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+ bitcoin.add_number_to_script(cltv_expiry) \
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+ bytes([opcodes.OP_CLTV, opcodes.OP_DROP, opcodes.OP_CHECKSIG, opcodes.OP_ENDIF, opcodes.OP_ENDIF])
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def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remotepubkey,
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payment_basepoint, remote_payment_basepoint,
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revocation_pubkey, delayed_pubkey, to_self_delay,
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funding_txid, funding_pos, funding_satoshis,
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local_amount, remote_amount, dust_limit_satoshis, htlcs=[]):
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pubkeys = sorted([bh2u(local_funding_pubkey), bh2u(remote_funding_pubkey)])
|
|
obs = get_obscured_ctn(ctn, payment_basepoint, remote_payment_basepoint)
|
|
locktime = (0x20 << 24) + (obs & 0xffffff)
|
|
sequence = (0x80 << 24) + (obs >> 24)
|
|
print_error('locktime', locktime, hex(locktime))
|
|
# commitment tx input
|
|
c_inputs = [{
|
|
'type': 'p2wsh',
|
|
'x_pubkeys': pubkeys,
|
|
'signatures':[None, None],
|
|
'num_sig': 2,
|
|
'prevout_n': funding_pos,
|
|
'prevout_hash': funding_txid,
|
|
'value': funding_satoshis,
|
|
'coinbase': False,
|
|
'sequence':sequence
|
|
}]
|
|
# commitment tx outputs
|
|
local_script = bytes([opcodes.OP_IF]) + bfh(push_script(bh2u(revocation_pubkey))) + bytes([opcodes.OP_ELSE]) + add_number_to_script(to_self_delay) \
|
|
+ bytes([opcodes.OP_CSV, opcodes.OP_DROP]) + bfh(push_script(bh2u(delayed_pubkey))) + bytes([opcodes.OP_ENDIF, opcodes.OP_CHECKSIG])
|
|
local_address = bitcoin.redeem_script_to_address('p2wsh', bh2u(local_script))
|
|
remote_address = bitcoin.pubkey_to_address('p2wpkh', bh2u(remotepubkey))
|
|
to_local = (bitcoin.TYPE_ADDRESS, local_address, local_amount)
|
|
to_remote = (bitcoin.TYPE_ADDRESS, remote_address, remote_amount)
|
|
c_outputs = [to_local, to_remote]
|
|
for script, msat_amount in htlcs:
|
|
c_outputs += [(bitcoin.TYPE_ADDRESS, bitcoin.redeem_script_to_address('p2wsh', bh2u(script)), msat_amount // 1000)]
|
|
# trim outputs
|
|
c_outputs = list(filter(lambda x:x[2]>= dust_limit_satoshis, c_outputs))
|
|
# create commitment tx
|
|
tx = Transaction.from_io(c_inputs, c_outputs, locktime=locktime, version=2)
|
|
tx.BIP_LI01_sort()
|
|
return tx
|
|
|
|
class Peer(PrintError):
|
|
|
|
def __init__(self, host, port, pubkey, request_initial_sync=False, network=None):
|
|
self.host = host
|
|
self.port = port
|
|
self.privkey = os.urandom(32) + b"\x01"
|
|
self.pubkey = pubkey
|
|
self.network = network
|
|
self.read_buffer = b''
|
|
self.ping_time = 0
|
|
self.channel_accepted = {}
|
|
self.funding_signed = {}
|
|
self.local_funding_locked = {}
|
|
self.remote_funding_locked = {}
|
|
self.initialized = asyncio.Future()
|
|
self.localfeatures = (0x08 if request_initial_sync else 0)
|
|
# view of the network
|
|
self.nodes = {} # received node announcements
|
|
self.channel_db = ChannelDB()
|
|
self.path_finder = LNPathFinder(self.channel_db)
|
|
|
|
def diagnostic_name(self):
|
|
return self.host
|
|
|
|
def ping_if_required(self):
|
|
if time.time() - self.ping_time > 120:
|
|
self.send_message(gen_msg('ping', num_pong_bytes=4, byteslen=4))
|
|
self.ping_time = time.time()
|
|
|
|
def send_message(self, msg):
|
|
message_type, payload = decode_msg(msg)
|
|
self.print_error("Sending '%s'"%message_type.upper(), payload)
|
|
l = encode(len(msg), 2)
|
|
lc = aead_encrypt(self.sk, self.sn(), b'', l)
|
|
c = aead_encrypt(self.sk, self.sn(), b'', msg)
|
|
assert len(lc) == 18
|
|
assert len(c) == len(msg) + 16
|
|
self.writer.write(lc+c)
|
|
|
|
async def read_message(self):
|
|
rn_l, rk_l = self.rn()
|
|
rn_m, rk_m = self.rn()
|
|
while True:
|
|
s = await self.reader.read(2**10)
|
|
if not s:
|
|
raise Exception('connection closed')
|
|
self.read_buffer += s
|
|
if len(self.read_buffer) < 18:
|
|
continue
|
|
lc = self.read_buffer[:18]
|
|
l = aead_decrypt(rk_l, rn_l, b'', lc)
|
|
length = int.from_bytes(l, byteorder="big")
|
|
offset = 18 + length + 16
|
|
if len(self.read_buffer) < offset:
|
|
continue
|
|
c = self.read_buffer[18:offset]
|
|
self.read_buffer = self.read_buffer[offset:]
|
|
msg = aead_decrypt(rk_m, rn_m, b'', c)
|
|
return msg
|
|
|
|
async def handshake(self):
|
|
hs = HandshakeState(self.pubkey)
|
|
msg = act1_initiator_message(hs, self.privkey)
|
|
# act 1
|
|
self.writer.write(msg)
|
|
rspns = await self.reader.read(2**10)
|
|
assert len(rspns) == 50
|
|
hver, alice_epub, tag = rspns[0], rspns[1:34], rspns[34:]
|
|
assert bytes([hver]) == hs.handshake_version
|
|
# act 2
|
|
hs.update(alice_epub)
|
|
myepriv, myepub = create_ephemeral_key(self.privkey)
|
|
ss = get_ecdh(myepriv, alice_epub)
|
|
ck, temp_k2 = get_bolt8_hkdf(hs.ck, ss)
|
|
hs.ck = ck
|
|
p = aead_decrypt(temp_k2, 0, hs.h, tag)
|
|
hs.update(tag)
|
|
# act 3
|
|
my_pubkey = privkey_to_pubkey(self.privkey)
|
|
c = aead_encrypt(temp_k2, 1, hs.h, my_pubkey)
|
|
hs.update(c)
|
|
ss = get_ecdh(self.privkey[:32], alice_epub)
|
|
ck, temp_k3 = get_bolt8_hkdf(hs.ck, ss)
|
|
hs.ck = ck
|
|
t = aead_encrypt(temp_k3, 0, hs.h, b'')
|
|
self.sk, self.rk = get_bolt8_hkdf(hs.ck, b'')
|
|
msg = hs.handshake_version + c + t
|
|
self.writer.write(msg)
|
|
# init counters
|
|
self._sn = 0
|
|
self._rn = 0
|
|
self.r_ck = ck
|
|
self.s_ck = ck
|
|
|
|
def rn(self):
|
|
o = self._rn, self.rk
|
|
self._rn += 1
|
|
if self._rn == 1000:
|
|
self.r_ck, self.rk = get_bolt8_hkdf(self.r_ck, self.rk)
|
|
self._rn = 0
|
|
return o
|
|
|
|
def sn(self):
|
|
o = self._sn
|
|
self._sn += 1
|
|
if self._sn == 1000:
|
|
self.s_ck, self.sk = get_bolt8_hkdf(self.s_ck, self.sk)
|
|
self._sn = 0
|
|
return o
|
|
|
|
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
|
|
f(payload)
|
|
|
|
def on_error(self, payload):
|
|
if payload["channel_id"] in self.channel_accepted:
|
|
self.channel_accepted[payload["channel_id"]].set_exception(LightningError(payload["data"]))
|
|
if payload["channel_id"] in self.funding_signed:
|
|
self.funding_signed[payload["channel_id"]].set_exception(LightningError(payload["data"]))
|
|
|
|
def on_ping(self, payload):
|
|
l = int.from_bytes(payload['num_pong_bytes'], byteorder="big")
|
|
self.send_message(gen_msg('pong', byteslen=l))
|
|
|
|
def on_accept_channel(self, payload):
|
|
self.channel_accepted[payload["temporary_channel_id"]].set_result(payload)
|
|
|
|
def on_funding_signed(self, payload):
|
|
channel_id = int.from_bytes(payload['channel_id'], byteorder="big")
|
|
self.funding_signed[channel_id].set_result(payload)
|
|
|
|
def on_funding_locked(self, payload):
|
|
channel_id = int.from_bytes(payload['channel_id'], byteorder="big")
|
|
self.remote_funding_locked[channel_id].set_result(payload)
|
|
|
|
def on_node_announcement(self, payload):
|
|
pubkey = payload['node_id']
|
|
signature = payload['signature']
|
|
h = bitcoin.Hash(payload['raw'][66:])
|
|
if not bitcoin.verify_signature(pubkey, signature, h):
|
|
return False
|
|
self.s = payload['addresses']
|
|
def read(n):
|
|
data, self.s = self.s[0:n], self.s[n:]
|
|
return data
|
|
addresses = []
|
|
while self.s:
|
|
atype = ord(read(1))
|
|
if atype == 0:
|
|
pass
|
|
elif atype == 1:
|
|
ipv4_addr = '.'.join(map(lambda x: '%d'%x, read(4)))
|
|
port = int.from_bytes(read(2), byteorder="big")
|
|
x = ipv4_addr, port, binascii.hexlify(pubkey)
|
|
addresses.append((ipv4_addr, port))
|
|
elif atype == 2:
|
|
ipv6_addr = b':'.join([binascii.hexlify(read(2)) for i in range(4)])
|
|
port = int.from_bytes(read(2), byteorder="big")
|
|
addresses.append((ipv6_addr, port))
|
|
else:
|
|
pass
|
|
continue
|
|
alias = payload['alias'].rstrip(b'\x00')
|
|
self.nodes[pubkey] = {
|
|
'alias': alias,
|
|
'addresses': addresses
|
|
}
|
|
self.print_error('node announcement', binascii.hexlify(pubkey), alias, addresses)
|
|
|
|
def on_init(self, payload):
|
|
pass
|
|
|
|
def on_channel_update(self, payload):
|
|
self.channel_db.on_channel_update(payload)
|
|
|
|
def on_channel_announcement(self, payload):
|
|
self.channel_db.on_channel_announcement(payload)
|
|
|
|
#def open_channel(self, funding_sat, push_msat):
|
|
# self.send_message(gen_msg('open_channel', funding_satoshis=funding_sat, push_msat=push_msat))
|
|
|
|
@aiosafe
|
|
async def main_loop(self):
|
|
self.reader, self.writer = await asyncio.open_connection(self.host, self.port)
|
|
await self.handshake()
|
|
# send init
|
|
self.send_message(gen_msg("init", gflen=0, lflen=1, localfeatures=self.localfeatures))
|
|
# read init
|
|
msg = await self.read_message()
|
|
self.process_message(msg)
|
|
# initialized
|
|
self.initialized.set_result(msg)
|
|
# loop
|
|
while True:
|
|
self.ping_if_required()
|
|
msg = await self.read_message()
|
|
self.process_message(msg)
|
|
# close socket
|
|
self.print_error('closing lnbase')
|
|
self.writer.close()
|
|
|
|
@aiosafe
|
|
async def channel_establishment_flow(self, wallet, config):
|
|
await self.initialized
|
|
temp_channel_id = os.urandom(32)
|
|
keys = get_unused_keys()
|
|
funding_pubkey, funding_privkey = next(keys)
|
|
revocation_basepoint, revocation_privkey = next(keys)
|
|
htlc_basepoint, htlc_privkey = next(keys)
|
|
delayed_payment_basepoint, delayed_privkey = next(keys)
|
|
base_secret = 0x000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f
|
|
per_commitment_secret_seed = 0x1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100.to_bytes(length=32, byteorder="big")
|
|
per_commitment_secret_index = 2**48 - 1
|
|
# amounts
|
|
funding_satoshis = 200000
|
|
push_msat = 0
|
|
local_feerate = 20000
|
|
dust_limit_satoshis = 10
|
|
to_self_delay = 144
|
|
ctn = 0
|
|
#
|
|
base_point = secret_to_pubkey(base_secret)
|
|
per_commitment_point_first = secret_to_pubkey(int.from_bytes(
|
|
get_per_commitment_secret_from_seed(per_commitment_secret_seed, per_commitment_secret_index),
|
|
byteorder="big"))
|
|
msg = gen_msg(
|
|
"open_channel",
|
|
temporary_channel_id=temp_channel_id,
|
|
chain_hash=bytes.fromhex(rev_hex(constants.net.GENESIS)),
|
|
funding_satoshis=funding_satoshis,
|
|
push_msat=push_msat,
|
|
dust_limit_satoshis=dust_limit_satoshis,
|
|
feerate_per_kw=local_feerate,
|
|
max_accepted_htlcs=5,
|
|
funding_pubkey=funding_pubkey,
|
|
revocation_basepoint=revocation_basepoint,
|
|
htlc_basepoint=htlc_basepoint,
|
|
payment_basepoint=base_point,
|
|
delayed_payment_basepoint=delayed_payment_basepoint,
|
|
first_per_commitment_point=per_commitment_point_first,
|
|
to_self_delay=to_self_delay
|
|
)
|
|
self.channel_accepted[temp_channel_id] = asyncio.Future()
|
|
self.send_message(msg)
|
|
try:
|
|
payload = await self.channel_accepted[temp_channel_id]
|
|
finally:
|
|
del self.channel_accepted[temp_channel_id]
|
|
remote_per_commitment_point = payload['first_per_commitment_point']
|
|
remote_funding_pubkey = payload["funding_pubkey"]
|
|
remote_delay = int.from_bytes(payload['to_self_delay'], byteorder="big")
|
|
remote_dust_limit_satoshis = int.from_bytes(payload['dust_limit_satoshis'], byteorder="big")
|
|
remote_revocation_basepoint = payload['revocation_basepoint']
|
|
remote_payment_basepoint = payload['payment_basepoint']
|
|
remote_delayed_payment_basepoint = payload['delayed_payment_basepoint']
|
|
funding_txn_minimum_depth = int.from_bytes(payload['minimum_depth'], byteorder="big")
|
|
self.print_error('remote dust limit', remote_dust_limit_satoshis)
|
|
self.print_error('remote delay', remote_delay)
|
|
self.print_error('funding_txn_minimum_depth', funding_txn_minimum_depth)
|
|
# create funding tx
|
|
pubkeys = sorted([bh2u(funding_pubkey), bh2u(remote_funding_pubkey)])
|
|
redeem_script = transaction.multisig_script(pubkeys, 2)
|
|
funding_address = bitcoin.redeem_script_to_address('p2wsh', redeem_script)
|
|
funding_output = (bitcoin.TYPE_ADDRESS, funding_address, funding_satoshis)
|
|
funding_tx = wallet.mktx([funding_output], None, config, 1000)
|
|
funding_txid = funding_tx.txid()
|
|
funding_index = funding_tx.outputs().index(funding_output)
|
|
# derive keys
|
|
localpubkey = derive_pubkey(base_point, remote_per_commitment_point)
|
|
localprivkey = derive_privkey(base_secret, remote_per_commitment_point)
|
|
remotepubkey = derive_pubkey(remote_payment_basepoint, per_commitment_point_first)
|
|
revocation_pubkey = derive_blinded_pubkey(revocation_basepoint, remote_per_commitment_point)
|
|
remote_revocation_pubkey = derive_blinded_pubkey(remote_revocation_basepoint, per_commitment_point_first)
|
|
local_delayedpubkey = derive_pubkey(delayed_payment_basepoint, per_commitment_point_first)
|
|
remote_delayedpubkey = derive_pubkey(remote_delayed_payment_basepoint, remote_per_commitment_point)
|
|
# compute amounts
|
|
htlcs = []
|
|
fee = local_feerate * overall_weight(len(htlcs)) // 1000
|
|
to_local_msat = funding_satoshis*1000 - push_msat
|
|
to_remote_msat = push_msat
|
|
local_amount = to_local_msat // 1000 - fee
|
|
remote_amount = to_remote_msat // 1000
|
|
# remote commitment transaction
|
|
remote_ctx = make_commitment(
|
|
ctn,
|
|
remote_funding_pubkey, funding_pubkey, localpubkey,
|
|
base_point, remote_payment_basepoint,
|
|
revocation_pubkey, remote_delayedpubkey, remote_delay,
|
|
funding_txid, funding_index, funding_satoshis,
|
|
remote_amount, local_amount, remote_dust_limit_satoshis)
|
|
remote_ctx.sign({bh2u(funding_pubkey): (funding_privkey, True)})
|
|
sig_index = pubkeys.index(bh2u(funding_pubkey))
|
|
sig = bytes.fromhex(remote_ctx.inputs()[0]["signatures"][sig_index])
|
|
r, s = sigdecode_der(sig[:-1], SECP256k1.generator.order())
|
|
sig_64 = sigencode_string_canonize(r, s, SECP256k1.generator.order())
|
|
funding_txid_bytes = bytes.fromhex(funding_txid)[::-1]
|
|
channel_id = int.from_bytes(funding_txid_bytes, byteorder="big") ^ funding_index
|
|
self.send_message(gen_msg("funding_created", temporary_channel_id=temp_channel_id, funding_txid=funding_txid_bytes, funding_output_index=funding_index, signature=sig_64))
|
|
self.funding_signed[channel_id] = asyncio.Future()
|
|
try:
|
|
payload = await self.funding_signed[channel_id]
|
|
finally:
|
|
del self.funding_signed[channel_id]
|
|
self.print_error('received funding_signed')
|
|
remote_sig = payload['signature']
|
|
# verify remote signature
|
|
local_ctx = make_commitment(
|
|
ctn,
|
|
funding_pubkey, remote_funding_pubkey, remotepubkey,
|
|
base_point, remote_payment_basepoint,
|
|
remote_revocation_pubkey, local_delayedpubkey, to_self_delay,
|
|
funding_txid, funding_index, funding_satoshis,
|
|
local_amount, remote_amount, dust_limit_satoshis)
|
|
pre_hash = bitcoin.Hash(bfh(local_ctx.serialize_preimage(0)))
|
|
if not bitcoin.verify_signature(remote_funding_pubkey, remote_sig, pre_hash):
|
|
raise Exception('verifying remote signature failed.')
|
|
# broadcast funding tx
|
|
self.local_funding_locked[channel_id] = asyncio.Future()
|
|
self.remote_funding_locked[channel_id] = asyncio.Future()
|
|
success, _txid = self.network.broadcast(funding_tx)
|
|
assert success
|
|
# wait until we see confirmations
|
|
def on_network_update(event, *args):
|
|
if event == 'updated':
|
|
conf = wallet.get_tx_height(funding_txid)[1]
|
|
if conf >= funding_txn_minimum_depth:
|
|
async def set_local_funding_locked_result():
|
|
try:
|
|
self.local_funding_locked[channel_id].set_result(1)
|
|
except (asyncio.InvalidStateError, KeyError) as e:
|
|
# FIXME race condition if updates come in quickly, set_result might be called multiple times
|
|
# or self.local_funding_locked[channel_id] might be deleted already
|
|
self.print_error('local_funding_locked.set_result error for channel {}: {}'.format(channel_id, e))
|
|
asyncio.run_coroutine_threadsafe(set_local_funding_locked_result(), asyncio.get_event_loop())
|
|
self.network.unregister_callback(on_network_update)
|
|
else:
|
|
self.print_error("unexpected network message:", event, args)
|
|
self.network.register_callback(on_network_update, ['updated']) # thread safe
|
|
|
|
try:
|
|
await self.local_funding_locked[channel_id]
|
|
finally:
|
|
del self.local_funding_locked[channel_id]
|
|
per_commitment_secret_index -= 1
|
|
per_commitment_point_second = secret_to_pubkey(int.from_bytes(
|
|
get_per_commitment_secret_from_seed(per_commitment_secret_seed, per_commitment_secret_index),
|
|
byteorder="big"))
|
|
self.send_message(gen_msg("funding_locked", channel_id=channel_id, next_per_commitment_point=per_commitment_point_second))
|
|
# wait until we receive funding_locked
|
|
try:
|
|
payload = await self.remote_funding_locked[channel_id]
|
|
finally:
|
|
del self.remote_funding_locked[channel_id]
|
|
self.print_error('Done waiting for remote_funding_locked', payload)
|
|
|
|
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_htlc')
|
|
|
|
|
|
|
|
# replacement for lightningCall
|
|
class LNWorker:
|
|
|
|
def __init__(self, wallet, network):
|
|
self.wallet = wallet
|
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self.network = network
|
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host, port, pubkey = network.config.get('lightning_peer', node_list[0])
|
|
pubkey = binascii.unhexlify(pubkey)
|
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port = int(port)
|
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self.peer = Peer(host, port, pubkey)
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self.network.futures.append(asyncio.run_coroutine_threadsafe(self.peer.main_loop(), asyncio.get_event_loop()))
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|
|
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def openchannel(self):
|
|
# todo: get utxo from wallet
|
|
# submit coro to asyncio main loop
|
|
self.peer.open_channel()
|
|
|
|
|
|
class ChannelInfo(PrintError):
|
|
|
|
def __init__(self, channel_announcement_payload):
|
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self.channel_id = channel_announcement_payload['short_channel_id']
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self.node_id_1 = channel_announcement_payload['node_id_1']
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|
self.node_id_2 = channel_announcement_payload['node_id_2']
|
|
|
|
self.capacity_sat = None
|
|
self.policy_node1 = None
|
|
self.policy_node2 = None
|
|
|
|
def set_capacity(self, capacity):
|
|
# TODO call this after looking up UTXO for funding txn on chain
|
|
self.capacity_sat = capacity
|
|
|
|
def on_channel_update(self, msg_payload):
|
|
assert self.channel_id == msg_payload['short_channel_id']
|
|
flags = int.from_bytes(msg_payload['flags'], byteorder="big")
|
|
direction = bool(flags & 1)
|
|
if direction == 0:
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|
self.policy_node1 = ChannelInfoDirectedPolicy(msg_payload)
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|
else:
|
|
self.policy_node2 = ChannelInfoDirectedPolicy(msg_payload)
|
|
self.print_error('channel update', binascii.hexlify(self.channel_id), flags)
|
|
|
|
def get_policy_for_node(self, node_id):
|
|
if node_id == self.node_id_1:
|
|
return self.policy_node1
|
|
elif node_id == self.node_id_2:
|
|
return self.policy_node2
|
|
else:
|
|
raise Exception('node_id {} not in channel {}'.format(node_id, self.channel_id))
|
|
|
|
|
|
class ChannelInfoDirectedPolicy:
|
|
|
|
def __init__(self, channel_update_payload):
|
|
self.cltv_expiry_delta = channel_update_payload['cltv_expiry_delta']
|
|
self.htlc_minimum_msat = channel_update_payload['htlc_minimum_msat']
|
|
self.fee_base_msat = channel_update_payload['fee_base_msat']
|
|
self.fee_proportional_millionths = channel_update_payload['fee_proportional_millionths']
|
|
|
|
|
|
class ChannelDB(PrintError):
|
|
|
|
def __init__(self):
|
|
self._id_to_channel_info = {}
|
|
self._channels_for_node = defaultdict(set) # node -> set(short_channel_id)
|
|
|
|
def get_channel_info(self, channel_id):
|
|
return self._id_to_channel_info.get(channel_id, None)
|
|
|
|
def get_channels_for_node(self, node_id):
|
|
"""Returns the set of channels that have node_id as one of the endpoints."""
|
|
return self._channels_for_node[node_id]
|
|
|
|
def on_channel_announcement(self, msg_payload):
|
|
short_channel_id = msg_payload['short_channel_id']
|
|
self.print_error('channel announcement', binascii.hexlify(short_channel_id))
|
|
channel_info = ChannelInfo(msg_payload)
|
|
self._id_to_channel_info[short_channel_id] = channel_info
|
|
self._channels_for_node[channel_info.node_id_1].add(short_channel_id)
|
|
self._channels_for_node[channel_info.node_id_2].add(short_channel_id)
|
|
|
|
def on_channel_update(self, msg_payload):
|
|
short_channel_id = msg_payload['short_channel_id']
|
|
try:
|
|
channel_info = self._id_to_channel_info[short_channel_id]
|
|
except KeyError:
|
|
pass # ignore channel update
|
|
else:
|
|
channel_info.on_channel_update(msg_payload)
|
|
|
|
def remove_channel(self, short_channel_id):
|
|
try:
|
|
channel_info = self._id_to_channel_info[short_channel_id]
|
|
except KeyError:
|
|
self.print_error('cannot find channel {}'.format(short_channel_id))
|
|
return
|
|
self._id_to_channel_info.pop(short_channel_id, None)
|
|
for node in (channel_info.node_id_1, channel_info.node_id_2):
|
|
try:
|
|
self._channels_for_node[node].remove(short_channel_id)
|
|
except KeyError:
|
|
pass
|
|
|
|
|
|
class LNPathFinder(PrintError):
|
|
|
|
def __init__(self, channel_db):
|
|
self.channel_db = channel_db
|
|
|
|
def _edge_cost(self, short_channel_id, start_node, payment_amt_msat):
|
|
"""Heuristic cost of going through a channel.
|
|
direction: 0 or 1. --- 0 means node_id_1 -> node_id_2
|
|
"""
|
|
channel_info = self.channel_db.get_channel_info(short_channel_id)
|
|
if channel_info is None:
|
|
return float('inf')
|
|
|
|
channel_policy = channel_info.get_policy_for_node(start_node)
|
|
cltv_expiry_delta = channel_policy.cltv_expiry_delta
|
|
htlc_minimum_msat = channel_policy.htlc_minimum_msat
|
|
fee_base_msat = channel_policy.fee_base_msat
|
|
fee_proportional_millionths = channel_policy.fee_proportional_millionths
|
|
if payment_amt_msat is not None:
|
|
if payment_amt_msat < htlc_minimum_msat:
|
|
return float('inf') # payment amount too little
|
|
if channel_info.capacity_sat is not None and \
|
|
payment_amt_msat // 1000 > channel_info.capacity_sat:
|
|
return float('inf') # payment amount too large
|
|
amt = payment_amt_msat or 50000 * 1000 # guess for typical payment amount
|
|
fee_msat = fee_base_msat + amt * fee_proportional_millionths / 1000000
|
|
# TODO revise
|
|
# paying 10 more satoshis ~ waiting one more block
|
|
fee_cost = fee_msat / 1000 / 10
|
|
cltv_cost = cltv_expiry_delta
|
|
return cltv_cost + fee_cost + 1
|
|
|
|
@profiler
|
|
def find_path_for_payment(self, from_node_id, to_node_id, amount_msat=None):
|
|
"""Return a path between from_node_id and to_node_id.
|
|
|
|
Returns a list of (node_id, short_channel_id) representing a path.
|
|
To get from node ret[n][0] to ret[n+1][0], use channel ret[n][1]
|
|
"""
|
|
# TODO find multiple paths??
|
|
|
|
# run Dijkstra
|
|
distance_from_start = defaultdict(lambda: float('inf'))
|
|
distance_from_start[from_node_id] = 0
|
|
prev_node = {}
|
|
nodes_to_explore = queue.PriorityQueue()
|
|
nodes_to_explore.put((0, from_node_id))
|
|
|
|
while nodes_to_explore.qsize() > 0:
|
|
dist_to_cur_node, cur_node = nodes_to_explore.get()
|
|
if cur_node == to_node_id:
|
|
break
|
|
if dist_to_cur_node != distance_from_start[cur_node]:
|
|
# queue.PriorityQueue does not implement decrease_priority,
|
|
# so instead of decreasing priorities, we add items again into the queue.
|
|
# so there are duplicates in the queue, that we discard now:
|
|
continue
|
|
for edge_channel_id in self.channel_db.get_channels_for_node(cur_node):
|
|
channel_info = self.channel_db.get_channel_info(edge_channel_id)
|
|
node1, node2 = channel_info.node_id_1, channel_info.node_id_2
|
|
neighbour = node2 if node1 == cur_node else node1
|
|
alt_dist_to_neighbour = distance_from_start[cur_node] \
|
|
+ self._edge_cost(edge_channel_id, cur_node, amount_msat)
|
|
if alt_dist_to_neighbour < distance_from_start[neighbour]:
|
|
distance_from_start[neighbour] = alt_dist_to_neighbour
|
|
prev_node[neighbour] = cur_node, edge_channel_id
|
|
nodes_to_explore.put((alt_dist_to_neighbour, neighbour))
|
|
else:
|
|
return None # no path found
|
|
|
|
# backtrack from end to start
|
|
cur_node = to_node_id
|
|
path = [(cur_node, None)]
|
|
while cur_node != from_node_id:
|
|
cur_node, edge_taken = prev_node[cur_node]
|
|
path += [(cur_node, edge_taken)]
|
|
path.reverse()
|
|
return path
|
|
|