243 lines
8.6 KiB
Python
243 lines
8.6 KiB
Python
# -*- coding: utf-8 -*-
|
|
"""
|
|
Created on Sun Mar 22 10:46:20 2020
|
|
|
|
@author: cpan
|
|
|
|
Simple client implementation with timeout feature to prevent hanging
|
|
|
|
"""
|
|
|
|
import sys
|
|
import socket
|
|
import json
|
|
import io
|
|
import struct
|
|
import hashlib
|
|
from Crypto import Random
|
|
from Crypto.PublicKey import RSA
|
|
from Crypto.Cipher import AES
|
|
|
|
HDRLEN = 2
|
|
PASSWORD = 'adminadmin'
|
|
|
|
class Message:
|
|
def __init__(self, sock, addr):
|
|
self._recv_buffer = bytearray(b"")
|
|
self.sock = sock
|
|
self.key = RSA.generate(2048, Random.new().read)
|
|
self.sessionkey = None
|
|
self.serverkey = None
|
|
self.addr = addr
|
|
self.handshake = False
|
|
|
|
def _json_encode(self,obj, encoding):
|
|
return json.dumps(obj, ensure_ascii=False).encode(encoding)
|
|
|
|
def _json_decode(self,json_bytes, encoding):
|
|
tiow = io.TextIOWrapper(
|
|
io.BytesIO(json_bytes), encoding=encoding, newline=""
|
|
)
|
|
obj = json.load(tiow)
|
|
tiow.close()
|
|
return obj
|
|
|
|
def _create_message(self, *, content_bytes, content_type, content_encoding):
|
|
if self.handshake:
|
|
# encrypt content_bytes
|
|
key = self.sessionkey + self.sessionkey[::-1]
|
|
iv = Random.new().read(AES.block_size)
|
|
cipher = AES.new(key, AES.MODE_CFB, iv)
|
|
data = iv + cipher.encrypt(content_bytes)
|
|
else:
|
|
data = content_bytes
|
|
|
|
jsonheader = {
|
|
"byteorder": sys.byteorder,
|
|
"content-type": content_type,
|
|
"content-encoding": content_encoding,
|
|
"content-length": len(data),
|
|
}
|
|
jsonheader_bytes = self._json_encode(jsonheader, "utf-8")
|
|
message_hdr = struct.pack(">H", len(jsonheader_bytes))
|
|
message = message_hdr + jsonheader_bytes + data
|
|
return message
|
|
|
|
def send_request(self, request):
|
|
content = request["content"]
|
|
content_type = request["type"]
|
|
content_encoding = request["encoding"]
|
|
if content_type == "text/json":
|
|
req = {
|
|
"content_bytes": self._json_encode(content, content_encoding),
|
|
"content_type": content_type,
|
|
"content_encoding": content_encoding,
|
|
}
|
|
else:
|
|
req = {
|
|
"content_bytes": content,
|
|
"content_type": content_type,
|
|
"content_encoding": content_encoding,
|
|
}
|
|
msg = self._create_message(**req)
|
|
print(f"sending request {repr(msg)} to {self.addr}")
|
|
self.sock.sendall(msg)
|
|
|
|
def read_to_buffer(self, length):
|
|
while len(self._recv_buffer) < length:
|
|
self._recv_buffer += self.sock.recv(4096)
|
|
|
|
def process_response(self):
|
|
# read and process protoheader (fixed length of 2 byte in network order)
|
|
self.read_to_buffer(HDRLEN)
|
|
_jsonheader_len = struct.unpack(">H", self._recv_buffer[:HDRLEN])[0]
|
|
self._recv_buffer = self._recv_buffer[HDRLEN:]
|
|
|
|
# read and process jsonheader
|
|
self.read_to_buffer(_jsonheader_len)
|
|
jsonheader = self._json_decode(self._recv_buffer[:_jsonheader_len], "utf-8")
|
|
self._recv_buffer = self._recv_buffer[_jsonheader_len:]
|
|
for reqhdr in ("byteorder", "content-length", "content-type",
|
|
"content-encoding",):
|
|
if reqhdr not in jsonheader:
|
|
raise ValueError(f'Missing required header "{reqhdr}".')
|
|
|
|
content_len = jsonheader["content-length"]
|
|
self.read_to_buffer(content_len)
|
|
data = self._recv_buffer[:content_len]
|
|
# decrypt data
|
|
iv = bytes(data[:AES.block_size])
|
|
encrypted = bytes(data[AES.block_size:])
|
|
key = self.sessionkey + self.sessionkey[::-1]
|
|
cipher = AES.new(key, AES.MODE_CFB, iv)
|
|
data = cipher.decrypt(encrypted)
|
|
self._recv_buffer = self._recv_buffer[content_len:]
|
|
if jsonheader["content-type"] == "text/json":
|
|
encoding = jsonheader["content-encoding"]
|
|
response = self._json_decode(data, encoding)
|
|
print("received response", repr(response), "from", self.addr)
|
|
content = response
|
|
result = content.get("result")
|
|
print(f"got result: {result}")
|
|
else:
|
|
# Binary or unknown content-type
|
|
response = data
|
|
print(
|
|
f'received {jsonheader["content-type"]} response from',
|
|
self.addr,
|
|
)
|
|
content = response
|
|
print(f"got response: {repr(content)}")
|
|
|
|
def _send_handshake(self, data):
|
|
response = {
|
|
"content_bytes": data,
|
|
"content_type": "binary/custom-server-binary-type",
|
|
"content_encoding": "binary",
|
|
}
|
|
message = self._create_message(**response)
|
|
self.sock.sendall(message)
|
|
|
|
def close(self):
|
|
self.sock.shutdown(socket.SHUT_RDWR)
|
|
self.sock.close()
|
|
self.sock = None
|
|
|
|
def _recv_handshake(self):
|
|
# read and process protoheader (fixed length of 2 byte in network order)
|
|
self.read_to_buffer(HDRLEN)
|
|
_jsonheader_len = struct.unpack(">H", self._recv_buffer[:HDRLEN])[0]
|
|
self._recv_buffer = self._recv_buffer[HDRLEN:]
|
|
|
|
# read and process jsonheader
|
|
self.read_to_buffer(_jsonheader_len)
|
|
jsonheader = self._json_decode(self._recv_buffer[:_jsonheader_len], "utf-8")
|
|
self._recv_buffer = self._recv_buffer[_jsonheader_len:]
|
|
for reqhdr in ("byteorder", "content-length", "content-type",
|
|
"content-encoding",):
|
|
if reqhdr not in jsonheader:
|
|
raise ValueError(f'Missing required header "{reqhdr}".')
|
|
|
|
content_len = jsonheader["content-length"]
|
|
self.read_to_buffer(content_len)
|
|
data = self._recv_buffer[:content_len]
|
|
self._recv_buffer = self._recv_buffer[content_len:]
|
|
sesskeyhash = data[-128:]
|
|
data = data[:-128]
|
|
encryptedsess = data[-256:]
|
|
halfsesskey = self.key.decrypt(bytes(encryptedsess))
|
|
data = data[:-256]
|
|
pubkeyhash = data[-128:]
|
|
pubkey = data[:-128]
|
|
if hashlib.sha3_512(pubkey).hexdigest().encode() != pubkeyhash:
|
|
self.close()
|
|
raise Exception('Server public key does not match hash')
|
|
if hashlib.sha3_512(halfsesskey).hexdigest().encode() != sesskeyhash:
|
|
self.close()
|
|
raise Exception('Server public key does not match hash')
|
|
self.sessionkey = halfsesskey
|
|
self.serverkey = RSA.importKey(pubkey)
|
|
print(f"Received server secrets correctly.")
|
|
|
|
def send_passphrase(self, passphrase):
|
|
passphrase = passphrase.encode()
|
|
passhash = hashlib.sha3_512(passphrase).hexdigest().encode()
|
|
sesshash = hashlib.sha3_512(self.sessionkey).hexdigest().encode()
|
|
data = self.serverkey.encrypt(passhash + sesshash, None)[0]
|
|
print(f'Sending passphrase + hash + sessionkey hash...')
|
|
self._send_handshake(data)
|
|
self.handshake = True
|
|
|
|
|
|
def create_request(action, value):
|
|
if action == "search":
|
|
return dict(
|
|
type="text/json",
|
|
encoding="utf-8",
|
|
content=dict(action=action, value=value),
|
|
)
|
|
else:
|
|
return dict(
|
|
type="binary/custom-client-binary-type",
|
|
encoding="binary",
|
|
content=bytes(action + value, encoding="utf-8"),
|
|
)
|
|
|
|
|
|
def main():
|
|
if len(sys.argv) != 5:
|
|
print("usage:", sys.argv[0], "<host> <port> <action> <value>")
|
|
sys.exit(1)
|
|
|
|
host, port = sys.argv[1], int(sys.argv[2])
|
|
addr = (host, port)
|
|
print("starting connection to", addr)
|
|
sock = socket.create_connection(addr)
|
|
sock.settimeout(None)
|
|
|
|
message = Message(sock, addr)
|
|
# security handshake
|
|
publickey = message.key.publickey().exportKey('PEM')
|
|
keyhash = hashlib.sha3_512(publickey).hexdigest().encode()
|
|
data = publickey + keyhash
|
|
print(f'Sending client public key and hash...')
|
|
message._send_handshake(data)
|
|
# receiving server secrets - public key and session key
|
|
message._recv_handshake()
|
|
message.send_passphrase(PASSWORD)
|
|
print('Handshake completed. Sever would close the sock if password wrong')
|
|
|
|
action, value = sys.argv[3], sys.argv[4]
|
|
request = create_request(action, value)
|
|
|
|
message.send_request(request)
|
|
|
|
# read and process response
|
|
message.process_response()
|
|
|
|
sock.shutdown(socket.SHUT_RDWR)
|
|
sock.close()
|
|
|
|
|
|
if __name__ == '__main__':
|
|
main() |