m2crypto_rsa_keypair_generation_string_encryption_decryption.py

1from M2Crypto import RSA
2
3# 1. Generate a new RSA key pair (1024 or 2048 bits)
4# The 'callback' is used for providing a passphrase if needed
5rsa_key = RSA.gen_key(2048, 65537)
6
7# 2. Define a message to encrypt
8message = b"This is a secret message."
9
10# 3. Encrypt the message using the public key
11# Use PKCS1 padding (standard)
12ciphertext = rsa_key.public_encrypt(message, RSA.pkcs1_padding)
13print(f"Encrypted: {ciphertext.hex()}")
14
15# 4. Decrypt the message using the private key
16decrypted = rsa_key.private_decrypt(ciphertext, RSA.pkcs1_padding)
17print(f"Decrypted: {decrypted.decode('utf-8')}")
18
19# 5. Optional: Save the keys to a file
20# rsa_key.save_key('private.pem', cipher=None)
21# rsa_key.save_pub_key('public.pem')