# -*- coding: utf-8 -*- import base64 import hashlib import struct import time import shared import structure class Header(object): def __init__(self, command, payload_length, payload_checksum): self.command = command self.payload_length = payload_length self.payload_checksum = payload_checksum def __repr__(self): return 'type: header, command: "{}", payload_length: {}, payload_checksum: {}'\ .format(self.command.decode(), self.payload_length, base64.b16encode(self.payload_checksum).decode()) def to_bytes(self): b = b'' b += shared.magic_bytes b += self.command.ljust(12, b'\x00') b += struct.pack('>L', self.payload_length) b += self.payload_checksum return b @classmethod def from_bytes(cls, b): magic_bytes, command, payload_length, payload_checksum = struct.unpack('>4s12sL4s', b) if magic_bytes != shared.magic_bytes: raise ValueError('magic_bytes do not match') command = command.rstrip(b'\x00') return cls(command, payload_length, payload_checksum) class Message(object): def __init__(self, command, payload): self.command = command self.payload = payload self.payload_length = len(payload) self.payload_checksum = hashlib.sha512(payload).digest()[:4] def __repr__(self): return '{}, payload_length: {}, payload_checksum: {}'\ .format(self.command.decode(), self.payload_length, base64.b16encode(self.payload_checksum).decode()) def to_bytes(self): b = Header(self.command, self.payload_length, self.payload_checksum).to_bytes() b += self.payload return b @classmethod def from_bytes(cls, b): h = Header.from_bytes(b[:24]) payload = b[24:] payload_length = len(payload) if payload_length != h.payload_length: raise ValueError('wrong payload length, expected {}, got {}'.format(h.payload_length, payload_length)) payload_checksum = hashlib.sha512(payload).digest()[:4] if payload_checksum != h.payload_checksum: raise ValueError('wrong payload checksum, expected {}, got {}'.format(h.payload_checksum, payload_checksum)) return cls(h.command, payload) class Version(object): def __init__(self, host, port, protocol_version=shared.protocol_version, services=shared.services, nonce=shared.nonce, user_agent=shared.user_agent): self.host = host self.port = port self.protocol_version = protocol_version self.services = services self.nonce = nonce self.user_agent = user_agent def __repr__(self): return 'version, protocol_version: {}, services: {}, host: {}, port: {}, nonce: {}, user_agent: {}'\ .format(self.protocol_version, self.services, self.host, self.port, base64.b16encode(self.nonce).decode(), self.user_agent) def to_bytes(self): payload = b'' payload += struct.pack('>I', self.protocol_version) payload += struct.pack('>Q', self.services) payload += struct.pack('>Q', int(time.time())) payload += structure.NetAddrNoPrefix(shared.services, self.host, self.port).to_bytes() payload += structure.NetAddrNoPrefix(shared.services, '127.0.0.1', 8444).to_bytes() payload += self.nonce payload += structure.VarInt(len(shared.user_agent)).to_bytes() payload += shared.user_agent payload += 2 * structure.VarInt(1).to_bytes() return Message(b'version', payload).to_bytes() @classmethod def from_bytes(cls, b): m = Message.from_bytes(b) payload = m.payload protocol_version, services, t, net_addr_remote, net_addr_local, nonce = \ struct.unpack('>IQQ26s26s8s', payload[:80]) net_addr_remote = structure.NetAddrNoPrefix.from_bytes(net_addr_remote) host = net_addr_remote.host port = net_addr_remote.port payload = payload[80:] user_agent_varint_length = structure.VarInt.length(payload[0]) user_agent_length = structure.VarInt.from_bytes(payload[:user_agent_varint_length]).n payload = payload[user_agent_varint_length:] user_agent = payload[:user_agent_length] payload = payload[user_agent_length:] if payload != b'\x01\x01': raise ValueError('message not for stream 1') return cls(host, port, protocol_version, services, nonce, user_agent) class Inv(object): def __init__(self, vectors): self.vectors = set(vectors) def __repr__(self): return 'inv, count: {}'.format(len(self.vectors)) def to_bytes(self): return Message(b'inv', structure.VarInt(len(self.vectors)).to_bytes() + b''.join(self.vectors)).to_bytes() @classmethod def from_message(cls, m): payload = m.payload vector_count_varint_length = structure.VarInt.length(payload[0]) vector_count = structure.VarInt.from_bytes(payload[:vector_count_varint_length]).n payload = payload[vector_count_varint_length:] vectors = set() while payload: vectors.add(payload[:32]) payload = payload[32:] if vector_count != len(vectors): raise ValueError('malformed Inv message, wrong vector_count') return cls(vectors) class GetData(object): def __init__(self, vectors): self.vectors = set(vectors) def __repr__(self): return 'getdata, count: {}'.format(len(self.vectors)) def to_bytes(self): return Message(b'getdata', structure.VarInt(len(self.vectors)).to_bytes() + b''.join(self.vectors)).to_bytes() @classmethod def from_message(cls, m): payload = m.payload vector_count_varint_length = structure.VarInt.length(payload[0]) vector_count = structure.VarInt.from_bytes(payload[:vector_count_varint_length]).n payload = payload[vector_count_varint_length:] vectors = set() while payload: vectors.add(payload[:32]) payload = payload[32:] if vector_count != len(vectors): raise ValueError('malformed GetData message, wrong vector_count') return cls(vectors) class Addr(object): def __init__(self, addresses): self.addresses = addresses def __repr__(self): return 'addr, count: {}'.format(len(self.addresses)) def to_bytes(self): return Message(b'addr', structure.VarInt(len(self.addresses)).to_bytes() + b''.join({addr.to_bytes() for addr in self.addresses})).to_bytes() @classmethod def from_message(cls, m): payload = m.payload addr_count_varint_length = structure.VarInt.length(payload[0]) addr_count = structure.VarInt.from_bytes(payload[:addr_count_varint_length]).n payload = payload[addr_count_varint_length:] addresses = set() while payload: addresses.add(structure.NetAddr.from_bytes(payload[:38])) payload = payload[38:] return cls(addresses)