I'd like to know whether the following modified CBC-MAC is secure (given a fixed IV). Source: an old course on Network Security Are there some obvious attacks I can't see?
Suppose that we want to develop a MAC scheme which is as secure as Triple-DES CBC-MAC and at the same time as efficient as Single-DES CBC-MAC. We come up with the following idea: Except the last ...
What block cipher is used for CBC-MAC? DES, AES, 3DES? Or it doesn't matter?
CBC-MAC, with fixed length message. Is it safe to return all ciphered blocks instead of the last? My intuition says it is less secure, since is gives an attacker more information. But how could one ...
I'm preparing myself to exam, but I have a lot of troubles with rigorous proofs. This post is very long, but this is because I remind here 2 long definitions. At the beginning I want to remind the ...