class Client:
__port = 5354
__key: str
def __init__(self, q, alpha):
self.__tcp = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.__s_des = SimpleDes()
self.__rc4 = RC4()
self.__encryption = None
self.__diffie_hellman = DiffieHellman(q, alpha)
def connect(self, host: str):
dest = (host, self.__port)
self.__tcp.connect(dest)
sockets_list = [sys.stdin, self.__tcp]
while True:
read_sockets, write_socket, error_socket = select.select(sockets_list, [], [])
for socks in read_sockets:
if socks == self.__tcp:
socks: socket.socket
messages: list = socks.recv(2048).decode().split("\x02")
controls = messages[1].split(" ")
if controls[0] == "\dh_end":
kp = controls[1]
self.__key = self.__diffie_hellman.calculate_sessionkey(int(kp))
print("Chave de diffie hellman trocadas!")
#self.__key = bin(self.__key)[2:].zfill(10)[-10:]
elif controls[0] == "\dh_begin":
kp = controls[1]
y = self.__diffie_hellman.calculate_pubkey()
self.__key = self.__diffie_hellman.calculate_sessionkey(int(kp))
print("Chave de diffie hellman trocadas!")
#self.__key = bin(self.__key)[2:].zfill(10)[-10:]
msg = "\dh_end " + str(y)
self.__tcp.send(bytes(msg.encode()))
else:
decrypted_message = self.__verify_encryption(messages[1])
print(messages[0] + decrypted_message)
else:
message: str = sys.stdin.readline()[:-1]
self.__erase_line()
if message[:5] == "\exit":
exit(1)
if message == "\dh_begin":
y = self.__diffie_hellman.calculate_pubkey()
msg = "\dh_begin " + str(y)
self.__tcp.send(bytes(msg.encode()))
else:
if self.__encryption:
encrypted_message: str = self.__encryption(message, True)
self.__tcp.send(bytes(encrypted_message.encode()))
else:
self.__tcp.send(bytes(message.encode()))
sys.stdout.write("<You> {}".format(self.__verify_start_encryption(message) + "\n"))
sys.stdout.flush()
def __use_s_des(self, message: str, encrypt: bool):
if encrypt:
execute = self.__s_des.encrypt
else:
execute = self.__s_des.decrypt
bin_message = list(format(ord(x), 'b') for x in message)
s_des_message = self.__execute_s_des(bin_message, execute)
return self.__binary_list_to_ascii(s_des_message)
def __execute_s_des(self, bin_message, execute: SimpleDes.encrypt) -> list:
s_des_message = list()
for byte in bin_message:
byte: str
s_des_message.append(execute(byte.zfill(8), self.__key))
return s_des_message
@staticmethod
def __binary_list_to_ascii(text: list) -> str:
return "".join([chr(int(i, 2)) for i in text])
def __verify_encryption(self, message: str):
if self.__encryption is None:
return self.__verify_start_encryption(message)
else:
decrypt_message = self.__encryption(message, False)
return self.__verify_start_encryption(decrypt_message)
def __use_rc4(self, message: str, encrypt: bool):
return self.__rc4.execute(message, self.__key)
def __start_encryption(self, message: str) -> bool:
commands = message.split(" ")
if commands[0] == "\crypt":
type_encryption = commands[1]
if type_encryption == "sdes":
self.__encryption = self.__use_s_des
self.__key = bin(int(self.__key))[2:].zfill(10)[-10:]
#self.__key = bin(self.__key)[2:].zfill(10)[-10:]
return True
'''if self.__have_quotes(commands[2]):
key = commands[2][1:-1]
self.__encryption = self.__use_s_des
if len(key) < 10:
self.__key = key.zfill(10)
else:
self.__key = key[:10]
return True
return False'''
elif type_encryption == "rc4":
self.__encryption = self.__use_rc4
self.__key = str(self.__key)
'''if self.__have_quotes(commands[2]):
self.__encryption = self.__use_rc4
#self.__key = commands[2][1:-1]
return True
return False'''
elif type_encryption == "none":
self.__encryption = None
return True
else:
return False
return False
def __check_type_encryption(self, message: str):
if self.__start_encryption(message):
if self.__encryption == self.__use_s_des:
return "Cifra Simple DES ativada"
elif self.__encryption == self.__use_rc4:
return "Cifra RC4 ativada"
else:
return "Comunicação sem cifra"
else:
return message
def __verify_start_encryption(self, message: str):
if self.__start_encryption(message):
return self.__check_type_encryption(message)
return message
def __erase_line(self):
CURSOR_UP_ONE = '\x1b[1A'
ERASE_LINE = '\x1b[2K'
sys.stdout.write(CURSOR_UP_ONE)
sys.stdout.write(ERASE_LINE)
@staticmethod
def __have_quotes(command: str) -> bool:
if command[0] == command[-1] == "\"":
return True
return False
def __del__(self):
print("saindo do chat...")
self.__tcp.close()
