Hi,

As part of an effort to enable automatic builds of TF-M in Zephyr, I've been trying to get the TF-M + Zephyr S/NS images building and passing on Zephyr's CI system.

The only missing requirements for building TF-M in a clean Zephyr SDK 0.10.1 based environment is the pycrypto module, which is used in the imgtool.py utility, specifically:

https://git.trustedfirmware.org/trusted-firmware-m.git/tree/bl2/ext/mcuboot/...

My concern is that this module is no longer actively maintained (last release was 2013!), and it seems like a poor decision to rely on something that isn't actively maintained when more recent alternative are available.

Is there a specific reason to keep this module in the script in favour of something more modern?

Best regards, Kevin