def check_cbc_padding_random(ciphertext, iv):
ciphertext = bytes(ciphertext)
iv = bytes(iv)
try:
plaintext = aes_cbc_decrypt(ciphertext, random_key, iv)
return True
except ValueError:
return False
def authenticate(ciphertext):
plaintext = aes_cbc_decrypt(ciphertext, random_key, random_iv)
plaintext = strip_pkcs7padding(plaintext)
info_dict = {}
for pair in plaintext.split(b';'):
k, v = pair.split(b'=')
info_dict[bytes(unquote(k.decode(errors='ignore')), encoding='utf-8')] = \
bytes(unquote(v.decode(errors='ignore')), encoding='utf-8')
if b'admin' in info_dict and info_dict[b'admin'] == b'true':
print('Logged in as admin. ')
return True, plaintext
else:
print('Logged in as regular user')
return False, plaintext
def admin_exists(self, ct):
"""
Detects if the admin parameter has been set to true in an input
encrypted CT.
@param ct [str]: Encrypted param string.
@returns [bool]: True if, when decrypted, the string contains
';admin=true;', False otherwise.
"""
pt = aes_cbc_decrypt(self.__key, ct, self.__iv)
vals = [
tup for tup in [param.split('=') for param in pt.split(';')]
if len(tup) == 2 and tup[0] == 'admin' and tup[1] == 'true'
]
return len(vals) > 0
def f2(enc, k, iv):
pt = aes_cbc_decrypt(enc, k, iv)
return TARGET in pt
def decrypt(self, ct):
return aes_cbc_decrypt(self.__key, ct, self.__iv)