def send_message(self, to, content):
"""Method for forming a text message to be sent to a target user."""
req = self.form_text_message(to, content)
with socket_lock:
send_message(req, self._socket, CLIENT_LOG)
self.process_server_answer(
receive_message(self._socket, CLIENT_LOG))
CLIENT_LOG.info(f'Sent a message to the user {to}')
def connection_init(self, port, ip):
"""Method for starting a server connection.
Opens socket, connects to the server over network, performs handshake and authorization."""
self._socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self._socket.settimeout(5)
connected = False
for i in range(5):
CLIENT_LOG.info(f'Connecting - try #{i + 1}')
try:
self._socket.connect((ip, port))
except (OSError, ConnectionRefusedError):
pass
else:
connected = True
break
time.sleep(1)
if not connected:
CLIENT_LOG.critical(
f"Couldn't connect to the server ({ip}:{port}).")
raise ServerError("Couldn't connect to the server!")
CLIENT_LOG.debug(
f'Connection with server {ip}:{port} established, starting AUTH process.'
)
passwd_bytes = self.password.encode('utf-8')
salt = self.username.lower().encode('utf-8')
passwd_hash = hashlib.pbkdf2_hmac('sha512', passwd_bytes, salt, 10000)
passwd_hash_string = binascii.hexlify(passwd_hash)
CLIENT_LOG.debug(f'Passwd hash ready: {passwd_hash_string}')
self.pubkey = self.keys.publickey().export_key().decode('ascii')
try:
with socket_lock:
send_message(self.form_presence_message(), self._socket,
CLIENT_LOG)
ans = receive_message(self._socket, CLIENT_LOG)
if JIM.RESPONSE in ans:
if ans[JIM.RESPONSE] == 400:
raise ServerError(ans[JIM.ERROR])
elif ans[JIM.RESPONSE] == ResCodes.AUTH_PROCESS:
ans_data = ans[JIM.DATA]
hash = hmac.new(passwd_hash_string,
ans_data.encode('utf-8'), 'MD5')
digest = hash.digest()
to_send = form_response(ResCodes.AUTH_PROCESS)
to_send[JIM.DATA] = binascii.b2a_base64(digest).decode(
'ascii')
send_message(to_send, self._socket, CLIENT_LOG)
self.process_server_answer(
receive_message(self._socket, CLIENT_LOG))
# self.process_server_answer(
# receive_message(self._socket, CLIENT_LOG))
except (OSError, json.JSONDecodeError) as err:
CLIENT_LOG.critical('Connection lost.', exc_info=err)
raise ServerError('Server connection lost!')
CLIENT_LOG.info('Server received our presence message.')
if __name__ == '__main__':
address, port, username, password = arg_parser()
app = QApplication(sys.argv)
init_dialog = UserNameDialog()
if not username or not password:
app.exec_()
if init_dialog.ok_pressed:
username = init_dialog.client_name.text()
password = init_dialog.client_passwd.text()
CLIENT_LOG.debug(f'Using name = {username}, pw = {password}')
else:
exit(0)
CLIENT_LOG.info(
f'Started a client, params: {address}:{port} (@{username})')
dir_path = os.path.dirname(os.path.realpath(__file__))
key_file = os.path.join(dir_path, f'{username}.key')
if not os.path.exists(key_file):
keys = RSA.generate(2048, os.urandom)
with open(key_file, 'wb') as key_f:
key_f.write(keys.export_key())
else:
with open(key_file, 'rb') as key_f:
keys = RSA.import_key(key_f.read())
CLIENT_LOG.debug('Keys loaded')
db = ClientBase(username)