MiNode/minode/message.py

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# -*- 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:
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raise ValueError('magic_bytes do not match')
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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:
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raise ValueError('wrong payload length, expected {}, got {}'.format(h.payload_length, payload_length))
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payload_checksum = hashlib.sha512(payload).digest()[:4]
if payload_checksum != h.payload_checksum:
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raise ValueError('wrong payload checksum, expected {}, got {}'.format(h.payload_checksum, payload_checksum))
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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')
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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')
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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')
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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)