def decrypt(self, data):
"""Decrypt the data using AES-CBC algorithm
The salt is automatically detected by looking for the SALTED_PREFIX
at the beginning of the string.
"""
if self.__is_salted(data):
(key, iv) = self.__openssl_key(self.__decrypted_key,
data[len(self.SALTED_PREFIX):16])
data = data[16:]
else:
iv = self.ZERO_IV
h = hashlib.md5()
h.update(self.__decrypted_key)
key = h.digest()
# Todo add exception raise
cipher = AES.new(key, AES.MODE_CBC, iv)
decrypted_data = cipher.decrypt(data)
return remove_padding(decrypted_data, AES.block_size)
def decrypt(self, data):
"""Decrypt the data using AES-CBC algorithm
The salt is automatically detected by looking for the SALTED_PREFIX
at the beginning of the string.
"""
if self.__is_salted(data):
(key, iv) = self.__openssl_key(
self.__decrypted_key, data[len(self.SALTED_PREFIX):16])
data = data[16:]
else:
iv = self.ZERO_IV
h = hashlib.md5()
h.update(self.__decrypted_key)
key = h.digest()
# Todo add exception raise
cipher = AES.new(key, AES.MODE_CBC, iv)
decrypted_data = cipher.decrypt(data)
return remove_padding(decrypted_data, AES.block_size)
def decrypt_key(self, password):
"""Decript the key using password
The password is first derived using the PBKF2 algorithm then
it decrypted using the AES-CBC algorithm
"""
pbkdf2 = PBKDF2(password, self.salt, self.ITERATIONS)
derived_key = pbkdf2.read(32)
key = derived_key[:16]
iv = derived_key[16:]
cipher = AES.new(key, AES.MODE_CBC, iv)
try:
self.__decrypted_key = remove_padding(cipher.decrypt(self.data),
AES.block_size)
except PaddingProtocolError:
raise DecryptionFailure, 'decryption failed for key %s' % \
self.identifier
self.__update_size(len(self.__decrypted_key) / 8)
if not self.__validate_decripted_key():
raise DecryptionFailure, 'decryption failed for key %s' % \
self.identifier
def decrypt_key(self, password):
"""Decript the key using password
The password is first derived using the PBKF2 algorithm then
it decrypted using the AES-CBC algorithm
"""
pbkdf2 = PBKDF2(password, self.salt, self.ITERATIONS)
derived_key = pbkdf2.read(32)
key = derived_key[:16]
iv = derived_key[16:]
cipher = AES.new(key, AES.MODE_CBC, iv)
try:
self.__decrypted_key = remove_padding(cipher.decrypt(self.data),
AES.block_size)
except PaddingProtocolError:
raise DecryptionFailure, 'decryption failed for key %s' % \
self.identifier
self.__update_size(len(self.__decrypted_key) / 8)
if not self.__validate_decripted_key():
raise DecryptionFailure, 'decryption failed for key %s' % \
self.identifier