Applied_Python_Cryptography/_3.4.1_DES_CBC.py at main · AnasZaatreh/Applied_Python_Cryptography · GitHub

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from Crypto.Cipher import DES
from Crypto.Util.Padding import pad, unpad
from Crypto.Random import get_random_bytes

def DES_CBC_encrypt(plaintext, DES_key, initialization_vector):

    DES_CBC_cipher = DES.new(DES_key, DES.MODE_CBC, iv=initialization_vector)

    ciphertext = DES_CBC_cipher.encrypt(pad(plaintext, DES.block_size))

    return ciphertext


def DES_CBC_decrypt(ciphertext, DES_key, initialization_vector):

    DES_CBC_cipher = DES.new(DES_key, DES.MODE_CBC, iv=initialization_vector)

    decrypted_plaintext = unpad(DES_CBC_cipher.decrypt(ciphertext),DES.block_size)

    return decrypted_plaintext


plaintext = input("Enter plaintext: ").encode("utf-8")

DES_key = get_random_bytes(8)
initialization_vector = get_random_bytes(8)

anas = str(DES_key)

ciphertext = DES_CBC_encrypt(plaintext, DES_key, initialization_vector)
decrypted_plaintext = DES_CBC_decrypt(ciphertext,DES_key, initialization_vector)

print("Encode PT:", plaintext)

print("Secret_Key: ", str(DES_key.hex()))
print("IV        : ", initialization_vector.hex())

print("Ciphertext: ", ciphertext.hex())
print("Decrypted : ", decrypted_plaintext.decode())