This module was created to easily implement a secure communication tunnel using Python 3.

The CryptoTCP class provides a simple way to set-up a TCP server/client with hybrid encryption, handling cryptographic and network operations such as: socket management, data transmission, key generation, encryption/decryption, encapsulation etc.

# This function is called each time nw data is received
def my_process_func(data):
    print("\n* * * * CALLING FUNC * * * *")
    print(str(data), "\n")

my_tcp_server = CryptoTCP()
my_tcp_server.listen_auto(8978, my_process_func, block=True)

The server will listen on port 8978 and automatically set-up a secure communication with the client. Every incoming message is then deciphered and passed to our processing function. The last instruction will block until handler is closed.

my_tcp_client = CryptoTCP()
my_tcp_client.connect_auto("127.0.0.1", 8978)

my_tcp_client.send_secure("(1) Hello, world!")
my_tcp_client.send_secure("(2) This exchange is secure.")

my_tcp_client.stop_remote_handler()

The client will connect to the server, set-up encryption and send two encrypted messages. After that, it will notify the server to stop waiting for data.

All private methods and attributes - those which start with a single underscore, e.g. _sig_post() - are generally not supposed to be called, they are meant for internal use only.

All cryptographic operations are handled by the CryptoEngine class, from which CryptoTCP inherits.

CryptoEngine can be used on it's own but does not provide generic encryption methods, it was designed to be used in conjonction with CryptoTCP.

Arguments (all optional):

• aes_byte_strenght (defaults to 16) : size in byte of the AES session key.
• rsa_bit_strenght (default to 2048) : size in bits of the RSA keychain.

To be continued...