MiNode/minode/message.py
2023-07-30 03:45:59 +03:00

264 lines
7.6 KiB
Python

# -*- coding: utf-8 -*-
"""Protocol message objects"""
import base64
import hashlib
import struct
import time
from . import shared, structure
class Header():
"""Common message header"""
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():
"""Common message structure"""
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():
"""The version message"""
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
( # unused: timestamp, net_addr_local
protocol_version, services, _, net_addr_remote, _, 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():
"""The inv message"""
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():
"""The getdata message"""
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():
"""The addr message"""
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)