When encryption is done using the AES-CBC algorithm, the encryption can be thought of as chaining the cipher texts with the previous ones and an IV. However, if its on CBC mode, we give our cipher text forward diffusive properties (i.e. if we change but i in our cipher, plaintext is change for all blocks after that). To make malleability attacks harder, one can chain the cipher texts during encryption on both directions (or implement something similar as in the bitLocker paper).
Does anyone know if there a implementation of pyCrypto that provides a chaining of the cipher texts using both direction?
One way that I thought of solving this was getting the original cipher text, reversing it using python and then feed it to pyCrypto. However, this seemed a little brute force because the whole point of pyCrypto is to take advantage of their C level implementation (while reversing a string would introduce a obvious unfortunate performance hit).