def test_break_rng_stream_cipher(self):
"""Challenge 24"""
seed_str = Crypto.gen_random_key(2)
seed = ord(seed_str[0]) << 8 | ord(seed_str[1])
mt_cipher = MT19937Cipher(seed)
prefix = Crypto.gen_random_key(23)
text = 'A'*14
cipher = mt_cipher.encrypt(prefix + text)
self.assertEquals(seed, Crypto.break_rng_stream_cipher(cipher, text))
def test_break_rng_stream_cipher(self):
"""Challenge 24"""
seed_str = Crypto.gen_random_key(2)
seed = ord(seed_str[0]) << 8 | ord(seed_str[1])
mt_cipher = MT19937Cipher(seed)
prefix = Crypto.gen_random_key(23)
text = 'A' * 14
cipher = mt_cipher.encrypt(prefix + text)
self.assertEquals(seed, Crypto.break_rng_stream_cipher(cipher, text))
def test_break_if_iv_is_same_as_key(self):
"""Challenge 27"""
key = Crypto.gen_random_key(16)
iv = key
oracle = lambda c: Crypto.decrypt_aes(c, key, AES.MODE_CBC, iv)
cipher = Crypto.encrypt_aes("X" * 48, key, AES.MODE_CBC, iv)
self.assertEquals(
key, Crypto.extract_key_if_key_is_same_as_key(cipher, oracle))
def test_break_if_iv_is_same_as_key(self):
"""Challenge 27"""
key = Crypto.gen_random_key(16)
iv = key
oracle = lambda c: Crypto.decrypt_aes(c, key, AES.MODE_CBC, iv)
cipher = Crypto.encrypt_aes("X"*48, key, AES.MODE_CBC, iv)
self.assertEquals(key,
Crypto.extract_key_if_key_is_same_as_key(cipher, oracle))
def test_md4_length_extension(self):
"""Challenge 30"""
orig_message = 'comment1=cooking%20MCs;userdata=foo;comment2=%20like' \
'%20a%20pound%20of%20bacon'
# this is not known to attacker.
key = Crypto.gen_random_key(43)
suffix = ';admin=true;'
orig_hash = md4(key + orig_message)
forged_message = MD4Hash.pad(key + orig_message) + suffix
forged_hash = md4(forged_message)
validate = lambda h: h == forged_hash
self.assertTrue(extend_md4(orig_hash, orig_message, suffix, validate))
def test_sha_length_extension(self):
"""Challenge 29"""
orig_message = 'comment1=cooking%20MCs;userdata=foo;comment2=%20like' \
'%20a%20pound%20of%20bacon'
# this is not known to attacker.
key = Crypto.gen_random_key(100)
suffix = ';admin=true;'
orig_sha = sha1(key + orig_message)
forged_message = Sha1Hash.pad(key + orig_message) + suffix
forged_sha = sha1(forged_message)
validate = lambda sha: sha == forged_sha
self.assertTrue(extend_sha1(orig_sha, orig_message, suffix, validate))
def test_sha_length_extension(self):
"""Challenge 29"""
orig_message = 'comment1=cooking%20MCs;userdata=foo;comment2=%20like' \
'%20a%20pound%20of%20bacon'
# this is not known to attacker.
key = Crypto.gen_random_key(100)
suffix = ';admin=true;'
orig_sha = sha1(key + orig_message)
forged_message = Sha1Hash.pad(key + orig_message) + suffix
forged_sha = sha1(forged_message)
validate = lambda sha: sha == forged_sha
self.assertTrue(extend_sha1(orig_sha, orig_message, suffix, validate))
def test_md4_length_extension(self):
"""Challenge 30"""
orig_message = 'comment1=cooking%20MCs;userdata=foo;comment2=%20like' \
'%20a%20pound%20of%20bacon'
# this is not known to attacker.
key = Crypto.gen_random_key(43)
suffix = ';admin=true;'
orig_hash = md4(key + orig_message)
forged_message = MD4Hash.pad(key + orig_message) + suffix
forged_hash = md4(forged_message)
validate = lambda h: h == forged_hash
self.assertTrue(extend_md4(orig_hash, orig_message, suffix, validate))
def test_prefix_aes_ecb_decryption(self):
"""Challenge 14"""
prefix = Crypto.gen_random_key(18)
target = "This is the target"
quote = lambda text: text
oracle, _, _ = Crypto.generate_aes_oracle(prefix, target, AES.MODE_ECB,
quote)
self.assertEqual(target, Crypto.decrypts_aes_ecb_byte_wise(oracle))
target = "A" * 16
oracle, _, _ = Crypto.generate_aes_oracle(prefix, target, AES.MODE_ECB,
quote)
self.assertEqual(target, Crypto.decrypts_aes_ecb_byte_wise(oracle))
def test_aes_ctr_encryption(self):
"""Challenge 18"""
counter = Crypto.gen_aes_stream_counter_simple()
key = "YELLOW SUBMARINE"
cipher = base64.b64decode("L77na/nrFsKvynd6HzOoG7GHTLXsTVu9qvY/2syLX" +\
"zhPweyyMTJULu/6/kXX0KSvoOLSFQ==")
text = "Yo, VIP Let's kick it Ice, Ice, baby Ice, Ice, baby "
self.assertEqual(text, Crypto.decrypt_aes(
cipher, key, AES.MODE_CTR, counter=counter))
# another test
key = Crypto.gen_random_key(16)
text = "Let there be light!"
counter = Crypto.gen_aes_stream_counter_simple()
cipher = Crypto.encrypt_aes(text, key, AES.MODE_CTR, counter=counter)
counter = Crypto.gen_aes_stream_counter_simple()
self.assertEqual(text, Crypto.decrypt_aes(
cipher, key, AES.MODE_CTR, counter=counter))
def test_aes_ctr_encryption(self):
"""Challenge 18"""
counter = Crypto.gen_aes_stream_counter_simple()
key = "YELLOW SUBMARINE"
cipher = base64.b64decode("L77na/nrFsKvynd6HzOoG7GHTLXsTVu9qvY/2syLX" +\
"zhPweyyMTJULu/6/kXX0KSvoOLSFQ==")
text = "Yo, VIP Let's kick it Ice, Ice, baby Ice, Ice, baby "
self.assertEqual(
text, Crypto.decrypt_aes(cipher,
key,
AES.MODE_CTR,
counter=counter))
# another test
key = Crypto.gen_random_key(16)
text = "Let there be light!"
counter = Crypto.gen_aes_stream_counter_simple()
cipher = Crypto.encrypt_aes(text, key, AES.MODE_CTR, counter=counter)
counter = Crypto.gen_aes_stream_counter_simple()
self.assertEqual(
text, Crypto.decrypt_aes(cipher,
key,
AES.MODE_CTR,
counter=counter))