ペイロードとはメッセージを送受信するデータ本体
Protocol version: 4bytes, little-endian
Network services of sender: 8bytes, little-endian
Timestamp, 8bytes, little-endian
Network service of receiver: 8bytes, little-endian
Network address of receiver, 16bytes, IPv4
Network port of receiver: 2bytes
Network services of sender: 8bytes, little-endian
Network address of sender: 16bytes, IPv4
Network port of sender: 2bytes
Nonce: 8bytes, used for communicating response
User agent
Optional flag of relay, based on BIP37(ブルームフィルターで使用)
VersionMessageクラス
class VersionMessage:
command = b'version'
def __init__(self, version=70015, services=0, timestamp=None,
receiver_services=0,
receiver_ip=b'\x00\x00\x00\x00', receiver_port=8333,
sender_services=0,
sender_ip=b'\x00\x00\x00\x00', sender_port=8333,
nonce=None, user_agent=b'/programmingbitcoin:0.1/',
latest_block=0, relay=False):
self.version = version
self.service = service
if timestamp is None:
self.timestamp = int(time.time())
else:
self.timestamp = timestamp
self.receiver_services = receiver_services
self.receiver_ip = receiver_ip
self.receiver_port = receiver_port
self.sender_services = sender_services
self.sender_ip = sender_ip
self.sender_port = sender_port
if nonce is None:
self.nonce = int_to_little_endian(randint(0, 2**64), 8)
else:
self.nonce = nonce
self.user_agent = user_agent
self.latest_block = latest_block
self.relay
serialize
def serialize(self):
result = int_to_little_endian(self.version, 4)
result += int_to_little_endian(self.services, 8)
result += int_to_little_endian(self.timestamp, 8)
result += int_to_little_endian(self.receiver_services, 8)
result += b'\x00' * 10 + b'\xff\xff' + self.receiver_ip
result += self.receiver_port.to_bytes(2, 'big')
result += int_to_little_endian(self.sender_services, 8)
result += b'\x00' * 10 + b'\xff\xff' + self.sender_ip
result += self.sender_port.to_bytes(2, 'big')
result += self.nonce
result += encode_varint(len(self.user_agent))
result += self.user_agent
result += int_to_little_endian(self.latest_block, 4)
if self.relay:
result += b'\x01'
else:
result += b'\x00'
return result
