Is it possible to generate a secure permutation F over 32-bit integers even if F(0) … F(n) is public knowledge?
I'm currently interested in the problem of generating random-looking URLs from sequential database IDs, like how they do it in link shorteners. One way to do this is to encrypt the sequential database ...
In the FFX spec, there is a note about using CMAC as the round function. Security notes. The round function F is constructed in such a way that the set of inputs on which the CBC-MAC is ...
Few block cipher modes has additional parameter , tweaks , especially the ones that are format preserving . Now the comments section of this blog entry says such tweaks can be used for BIN numbers, ...
Can you create a strong blockcipher with small blocksize, given a strong blockcipher of conventional blocksize?
Suppose I want a strong 20-bit blockcipher. In other words, I want a function that takes a key (suppose the key is 128 bits), and implements a permutation from 20 bits to 20 bits. The set of ...