How to change number of rounds?

Embedded Security ChipWhisperer Software
1

Is there any way to change the number of rounds? For example the AES code seems to have 12 rounds, what if I wanted it to have 4 rounds only? Is it possible, if yes then kindly guide me.

2

AES128 has 10 rounds. You could modify the crypto code to change the number of rounds, but this is something you’ll have to figure out for yourself.

If you’re curious, changing the number of rounds isn’t really something that affects side channel attacks. This is because we typically target either the very start or the very end of the encryption operation using the plaintext or ciphertext, respectively.

3

@Alex_Dewar it means i need to change .c file in crypto folder? In which AES is implemented.

4

Yeah, that’s correct.

1 Like
5

Thanks @Alex_Dewar for very helpful guide