The contents of this page should therefore be treated as merely an exercise, and readers wishing to use them must accept their own responsibility for doing so. They are inexpensive and readily available, and should be used for any serious encryption needs.

Readers are remainded that there are numerous professionally developed encryption products. Although I have done all I can to make sure the results are correct and reproducible, the algorithms presented on this page has not been extensively reviewed or tested, so that errors and omissions cannot be ruled out.

TEST_MSG = b'this is a short test message.I created this page during the Covid pandemic lockdown of 2021, partly to have something to do, partly to teach myself encryption, and partly to teach myself Python. Hashfromsignature = pow(signature, publickey.e, publickey.n) Msg_hash = int.from_bytes(sha512(clear_text).digest(), byteorder='big') Session_key = crypt(enc_session_key.encode().fromhex(enc_session_key))Īes_cipher = AES.new(session_key, AES.MODE_EAX, nonce=nonce.encode().fromhex(nonce))Ĭlear_text = aes_crypt(aes_cipher_text.encode().fromhex(aes_cipher_text))Īes_cipher.verify(tag.encode().fromhex(tag)) Hashes clear text and compares to signature Uses private key to decrypt the session keyĬipher is created with supplied key, and nonceĬlear text is returned and authenticity status is returned

'''encrypted session key is encoded and returned from hex Return aes_cipher_text.hex(), tag.hex(), nonce.hex(), enc_session_key.hex(), signatureĭef decrypt_msg(aes_cipher_text, tag, nonce, enc_session_key, privatekey, publickey, signature): Signature = pow(msg_hash, privatekey.d, privatekey.n) Msg_hash = int.from_bytes(sha512(msg_body).digest(), byteorder='big') Hashes clear text message and creates signature'''Īes_cipher = AES.new(session_key, AES.MODE_EAX)Īes_cipher_text, tag = aes_cipher.encrypt_and_digest(msg_body)Įnc_session_key = rsa_cipher.encrypt(session_key) Returns the cipher text, tag, nonce, and the encrypted session key in hex format '''Generates the session key, then creates the nonce and cipher. pem secured with a passphrase'''ĭef encrypt_msg(msg_body, publickey, privatekey): In actual usage private key is exported to. ''' Generates the rsa key pair and returns them. Requires the P圜ryptodome module but is imported as Crypto'''įrom Crypto.Random import get_random_bytes '''Hybrid AES/RSA encryption, integrity, and repudiation proof of concept. I wondering if anyone could give me feedback on whether or not this is a secure way to implement AES/RSA hybrid encryption and signatures in python 3 with the P圜ryptodome module.Īll of the encoding and to/from hex format is just there because that's the format I intend to transfer it in.

Crypto library python rsa decrypt