Fixed plaintext transmission - CW1173 / CW305

Hi to the community,

I wanted to know if there is a way of sending arbitrary number of fixed plaintexts to ChipWhisperer-Lite or ChipWhisperer-Artix. From what I understand, that is done by manually changing the plaintext value in the “Fixed Plaintext” option given by the Capture software. Am I right? Is this the only way?

Thank you in advance for your responses!

Kind regards,
Nassos

Hi,

I think you might have to start an modify/copy some code here:

For example the load input method
https://github.com/newaetech/chipwhisperer/blob/master/software/chipwhisperer/capture/targets/SimpleSerial.py#L252

You may want to write your own module, extending acq_patterns base class, and put in your chipwhisperer/software/chipwhisperer/capture/acq_patterns directory:

“What to tweak?
acq_patterns - Has the modules that generate the keys. If you want to generate custom key or plaintext sequences, or read it from a file, this is the place to go.”

wiki.newae.com/Adding_Modules/Parameters

1 Like

Thanks for the answers while I’m travelling, everyone :slight_smile:

I think Adriel’s idea is the way to go. There’s a good example of sending very specific plaintexts in the TVLA test acquisition pattern. The point here is that you can write any plaintext/key generation code in newPair(). In this case, the TVLA test pattern is to randomly interleave “pseudo-random” plaintexts and a single fixed plaintext while keeping the same key.

@gdeon, @aziesemer, @ExMachina

Thank you all for your clear instructions!