I followed the tutorial (PA_HW_CW305_1-Attacking_AES_on_an_FPGA) to implement the CPA attack, but I can not get all correct key when I use CPA to attack 32-bit AES. Not being able to just use CPA on non-128-bit AES may have something to do with how the cpa algorithm decides points of interest.
attack = cwa.cpa(project, cwa.leakage_models.last_round_state_diff)
I am confused about this line of code how to determine which point in the power trace is the point of interest required by the CPA algorithm.
I searched for some information in /software/chipwhisperer/analyzer/attacks.
In AES128_8bit.py, the leakage model gives us hammering distance.I don’t think it has anything to do with points of interest, but maybe I’m wrong.
In progressive.py, it uses different traces to get output stats, but I don’t understand how it figures out points of interest in power trace.
Any suggestions would be appreciated.