pycryptodomex

from Cryptodome.Cipher import AES from Cryptodome.Random import get_random_bytes from Cryptodome.Util.Padding import pad, unpad # --- Encryption --- # Generate a random 16-byte key for AES-128 key = get_random_bytes(16) # Generate a random 16-byte IV for CBC mode iv = get_random_bytes(16) # The data to encrypt must be bytes data_to_encrypt = b"My secret message that needs to be encrypted." # Create an AES cipher object in CBC mode cipher = AES.new(key, AES.MODE_CBC, iv) # Pad the data to be a multiple of the block size (16 bytes for AES) padded_data = pad(data_to_encrypt, AES.block_size) # Encrypt the padded data ciphertext = cipher.encrypt(padded_data) print(f"Original data: {data_to_encrypt}") print(f"Key (hex): {key.hex()}") print(f"IV (hex): {iv.hex()}") print(f"Ciphertext (hex): {ciphertext.hex()}") # --- Decryption --- # In a real scenario, key, iv, and ciphertext would be transmitted # to the receiver. For this example, we reuse them. # Create a new AES cipher object for decryption (same key and IV) decipher = AES.new(key, AES.MODE_CBC, iv) # Decrypt the ciphertext decrypted_padded_data = decipher.decrypt(ciphertext) # Unpad the decrypted data to get the original plaintext decrypted_data = unpad(decrypted_padded_data, AES.block_size) print(f"Decrypted data: {decrypted_data}") assert decrypted_data == data_to_encrypt print("Encryption and decryption successful!")