gistfile1.txt

import struct
import socket
import time
import hashlib
import random
from p2p.encoding import ser_string

magic = bytes.fromhex("f9beb4d9")

class CAddress(object):
    def __init__(self):
        self.nTime = int(time.time())
        self.nServices = 1
        self.pchReserved = b"\x00" * 10 + b"\xff" * 2
        self.ip = "0.0.0.0"
        self.port = 0

    def deserialize(self, f):
        self.nTime = struct.unpack(b"<I", f.read(4))[0]
        self.nServices = struct.unpack(b"<Q", f.read(8))[0]
        self.pchReserved = f.read(12)
        self.ip = socket.inet_ntoa(f.read(4))
        self.port = struct.unpack(b">H", f.read(2))[0]

    def serialize(self):
        r = b""
        r += struct.pack(b"<I", self.nTime)
        r += struct.pack(b"<Q", self.nServices)
        r += self.pchReserved
        r += socket.inet_aton(self.ip)
        r += struct.pack(b">H", self.port)
        return r

    def __repr__(self):
        return "CAddress(nTime=%d nServices=%i ip=%s port=%i)" % (self.nTime, self.nServices, self.ip, self.port)


class VersionMessage(object):
    def __init__(self):
        self.magic = magic
        self.nVersion = 60002
        self.nServices = 9
        self.nTime = int(time.time())
        self.addrTo = CAddress()
        self.addrFrom = CAddress()
        self.nNonce = random.getrandbits(64)
        self.strSubVer = b'/python-bitcoin-0.0.1/'
        self.nStartingHeight = -1

    @property
    def command(self) -> bytes:
        return b"version"

    def serialize(self):
        r = b""
        r += struct.pack(b"<i", self.nVersion)
        r += struct.pack(b"<Q", self.nServices)
        r += struct.pack(b"<q", self.nTime)
        r += self.addrTo.serialize()
        r += self.addrFrom.serialize()
        r += struct.pack(b"<Q", self.nNonce)
        r += ser_string(self.strSubVer)
        r += struct.pack(b"<i", self.nStartingHeight)
        return r

    def finalize(self):
        payload = self.serialize()
        checksum = hashlib.sha256(hashlib.sha256(payload).digest()).digest()
        result = b""
        result += self.magic
        result += struct.pack('12s', self.command)
        result += struct.pack("<I", len(payload))
        result += checksum[:4]
        result += payload
        return result



ip = socket.gethostbyname("127.0.0.1")
port = 8333
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print("connected to node...")
sock.connect((ip, port))

print("sending version packet")
sock.send(VersionMessage().finalize())

while 1:
    msg = sock.recv(2 ** 10)
    if not msg:
        print("done")
        exit()
    else:
        print(msg)