class TestCbc(unittest.TestCase):
"""
Tests AES-128 in CBC mode.
"""
def setUp(self):
self.aes = AES(b'\x00' * 16)
self.iv = b'\x01' * 16
self.message = b'my message'
def test_single_block(self):
""" Should be able to encrypt and decrypt single block messages. """
ciphertext = self.aes.encrypt_cbc(self.message, self.iv)
self.assertEqual(self.aes.decrypt_cbc(
ciphertext, self.iv), self.message)
# Since len(message) < block size, padding won't create a new block.
self.assertEqual(len(ciphertext), 16)
def test_wrong_iv(self):
""" CBC mode should verify the IVs are of correct length."""
with self.assertRaises(AssertionError):
self.aes.encrypt_cbc(self.message, b'short iv')
with self.assertRaises(AssertionError):
self.aes.encrypt_cbc(self.message, b'long iv' * 16)
with self.assertRaises(AssertionError):
self.aes.decrypt_cbc(self.message, b'short iv')
with self.assertRaises(AssertionError):
self.aes.decrypt_cbc(self.message, b'long iv' * 16)
def test_different_iv(self):
""" Different IVs should generate different ciphertexts. """
iv2 = b'\x02' * 16
ciphertext1 = self.aes.encrypt_cbc(self.message, self.iv)
ciphertext2 = self.aes.encrypt_cbc(self.message, iv2)
self.assertNotEqual(ciphertext1, ciphertext2)
plaintext1 = self.aes.decrypt_cbc(ciphertext1, self.iv)
plaintext2 = self.aes.decrypt_cbc(ciphertext2, iv2)
self.assertEqual(plaintext1, plaintext2)
self.assertEqual(plaintext1, self.message)
def test_whole_block_padding(self):
""" When len(message) == block size, padding will add a block. """
block_message = b'M' * 16
ciphertext = self.aes.encrypt_cbc(block_message, self.iv)
self.assertEqual(len(ciphertext), 32)
self.assertEqual(self.aes.decrypt_cbc(
ciphertext, self.iv), block_message)
def test_long_message(self):
""" CBC should allow for messages longer than a single block. """
long_message = b'M' * 100
ciphertext = self.aes.encrypt_cbc(long_message, self.iv)
self.assertEqual(self.aes.decrypt_cbc(
ciphertext, self.iv), long_message)
class TestCbc(unittest.TestCase):
"""
Tests AES-128 in CBC mode.
"""
def setUp(self):
self.aes = AES(b'\00' * 16)
self.iv = b'\01' * 16
self.message = b'my message'
def test_single_block(self):
""" Should be able to encrypt and decrypt single block messages. """
ciphertext = self.aes.encrypt_cbc(self.message, self.iv)
self.assertEqual(self.aes.decrypt_cbc(ciphertext, self.iv), self.message)
# Since len(message) < block size, padding won't create a new block.
self.assertEqual(len(ciphertext), 16)
def test_wrong_iv(self):
""" CBC mode should verify the IVs are of correct length."""
with self.assertRaises(AssertionError):
self.aes.encrypt_cbc(self.message, b'short iv')
with self.assertRaises(AssertionError):
self.aes.encrypt_cbc(self.message, b'long iv' * 16)
with self.assertRaises(AssertionError):
self.aes.decrypt_cbc(self.message, b'short iv')
with self.assertRaises(AssertionError):
self.aes.decrypt_cbc(self.message, b'long iv' * 16)
def test_different_iv(self):
""" Different IVs should generate different ciphertexts. """
iv2 = b'\02' * 16
ciphertext1 = self.aes.encrypt_cbc(self.message, self.iv)
ciphertext2 = self.aes.encrypt_cbc(self.message, iv2)
self.assertNotEqual(ciphertext1, ciphertext2)
plaintext1 = self.aes.decrypt_cbc(ciphertext1, self.iv)
plaintext2 = self.aes.decrypt_cbc(ciphertext2, iv2)
self.assertEqual(plaintext1, plaintext2)
self.assertEqual(plaintext1, self.message)
def test_whole_block_padding(self):
""" When len(message) == block size, padding will add a block. """
block_message = b'M' * 16
ciphertext = self.aes.encrypt_cbc(block_message, self.iv)
self.assertEqual(len(ciphertext), 32)
self.assertEqual(self.aes.decrypt_cbc(ciphertext, self.iv), block_message)
def test_long_message(self):
""" CBC should allow for messages longer than a single block. """
long_message = b'M' * 100
ciphertext = self.aes.encrypt_cbc(long_message, self.iv)
self.assertEqual(self.aes.decrypt_cbc(ciphertext, self.iv), long_message)
'''
Created on Apr 21, 2020
@author: KSHITIZ CHATURVEDI
'''
from aes import AES
from aes import unpad
if __name__ == '__main__':
text = "Two One Nine TwoTwo One Nine abcd" #input("Enter plain text")
key = "Thats My Kung Fu" #input("Enter key")
iv = "given initializa"
obj = AES(key)
cipher = obj.encrypt_cbc(text, iv)
print(cipher)
msg = obj.decrypt_cbc(cipher, iv)
print(msg)
msgstr = ""
for i in msg:
for j in i:
msgstr += chr(j)
print(unpad(msgstr))
"The length of the initialization vector needs to be 16, please enter 16 bytes long iv\n"
)
obj = AES(key)
cipher = [[
82, 214, 73, 255, 189, 148, 31, 109, 36, 213, 241, 19, 240, 128,
113, 142
],
[
248, 241, 148, 140, 143, 63, 222, 195, 202, 210, 244, 74,
102, 0, 190, 200
],
[
29, 45, 179, 186, 183, 88, 115, 91, 115, 240, 60, 133,
170, 156, 139, 215
]]
msg = obj.decrypt_cbc(cipher, iv)
msgstr = ""
for i in msg:
for j in i:
msgstr += chr(j)
print("Here is your decrypted message:", unpad(msgstr))
elif choice == 3:
text = input("Enter the text to be encrypted:\n")
key = input("Enter 16 bytes long encryption key:\n")
while (len(key) != 16):
key = input(
"The length of the key needs to be 16, please enter 16 bytes long key\n"
)
iv = input("Enter 16 bytes long initialization vector:\n")
while (len(iv) != 16):
