support for date_time

[gchiii]

If we have an RTC , or are syncing with some form of NTP, how can we hook in to the underlying mbedtls to provide date /time functions possibly through the MBEDTLS_PLATFORM_GMTIME_R_ALT?
will this allow me to properly handle accepting certificates that have not expired yet?

[bjoernQ]

I guess the C code needs to be compiled with

MBEDTLS_HAVE_TIME_DATE
MBEDTLS_HAVE_TIME
MBEDTLS_PLATFORM_GMTIME_R_ALT

And the user would need to provide an implementation for mbedtls_platform_gmtime_r - I can imagine having a feature for this which will opt-out of the pre-compiled libraries and builds mbedtls with the needed settings

[ivmarkov]

With #99 making on-the-fly compilation so much easier, I don't see why we should not support this (I mean, not necessarily with the pre-compiled libs, but with on-the-fly compilation initially).

@gchiii Are you still interested in this?