Question about firmware in Part 1, Topic 2

1

Hello,

I am challenging the chipwhisperer tutorial of fault injection
Part1, Topic2:Clock Glitching to Dump Memory (MAIN)

I could run all the commands, but I have a question.

In this tutorial, we are attacking glitch_loop which is target firmware, but when is this glitch_loop start running?( I could not find it in IN[17])

Do I have to write the program to the microcompuer?(If so, I’d like to know how to do it.)

Sorry for the rudimentary question, but please let me know.

I am using chipwhisperer XMEGA,
windows 10

Thank you.

2

Hi,

I’m a little confused as to what you mean: glitch_loop() is in the first lab (Intro to clock glitching) and the memory dump is the third lab.

glitch_loop() gets called when the target receives a 'g' command with no data bytes, which corresponds to "g\n" for SimpleSerial V1. The firmware setup for this command can be found at: https://github.com/newaetech/chipwhisperer/blob/develop/hardware/victims/firmware/simpleserial-glitch/simpleserial-glitch.c#L169. This firmware gets built at the beginning of the lab with the make bash command and uploaded to the target with cw.program_target().

Hope that helps,

Alex

3

Hello,

Thank you for your reply, and I understand the firmware upload system !
By the way, when does the simpleserial-glitch.c executed in the code IN[17]?
Is it correct that simpleserial-glitch.c is always running and glitch_loop is executed when 'g' wad inserted by target_write?

(glitch_loop is in the first llab, but it seems that the name of the first lab is “Part 1, Topic 2: Clock Glitching to Dump Memory (MAIN)”)

Thank you.

4

Yup, that’s correct.

Thanks for the heads up there - this is a typo in the solution version of the lab. I’ll get that fixed up.

Alex

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