Create smart card emulation type firmware

[mithro]

https://github.com/thomastsai/STM32F2xx_StdPeriph_Lib_V1.1.0/tree/master/Project/STM32F2xx_StdPeriph_Examples/USART/SmartCard
http://www.keil.com/smartcards/
https://github.com/OpenSC/OpenSC/wiki

[aze00]

I am working on this here; https://github.com/aze00/gnuk

It is in early experimental stage, and I don't have hardware to debug it, but it shows that it is possible to have a, heavily stripped down, but working gnuk (one crypto suite only) on the tomu.

From the view count of the topic in this discussion; https://groups.google.com/forum/#!topic/tomu-discuss/vXPS6CeSsFw it seems there is some interest for this, so I am publishing the code so that others could maybe help with the porting and/or the testing.

[aze00]

PR #35 created as a for dev/discussions

[hevisko]

@aze00 I'd like to replace the PolarSSL's software AES with the EFM32HG309's AES128 module (can only do AES128), which should firstly gain some performance increases, but definitely should cut on some code size or RAM usage.

Questions:

1. is AES192 & AES256 "needed", or can we settle (for now) only on the AES128 modes?

2. I'm looking at modifying and "packaging" the SiLabs's ARM mbed code found at https://github.com/ARMmbed/mbed-os/blob/master/targets/TARGET_Silicon_Labs/TARGET_EFM32/TARGET_EFM32HG/device/efm32hg_aes.h and https://github.com/ARMmbed/mbed-os/blob/master/targets/TARGET_Silicon_Labs/TARGET_EFM32/emlib/src/em_aes.c as the basis, and just want to know if there are any glaring license issues I should be aware of?

3. Anything I should be aware of?

[ringerc]

Anyone here played with porting over OpenSC to a Tomu target?