Previously we used `gettimeofday()` for Mbed TLS timing, but its
implementation provided by Mbed OS is only precise to seconds. The
microsecond component of the output `struct timeval` is always set
to zero. But Mbed TLS requires millisecond precision.
To provide required timing precision, switch to use `LowPowerTicker`
or (microsecond) `Ticker`. `LowPowerTicker` is preferred as it saves
power and Mbed TLS does not require microsecond precision.
We get a linker warning with the recently added timing module
implementation for Mbed. This is because there is Mbed TLS also ships a
file called timing.c, which we are including in Mbed OS also. With CLI
1, we get an error about unique object files because of the similarly
named implementation files.
Object file timing.o is not unique! It could be made from: mbed-os/connectivity/mbedtls/source/timing.c mbed-os/connectivity/mbedtls/platform/src/timing.cpp
Rename the Mbed timing module implementation to timing_mbed.cpp to avoid
this naming conflict.
Fixes: b8781e527b ("mbedtls: Add an alt implementation of timing")
Fixes#14759
Don't attempt to use default_random_seed unless both PSA and Experimental API
support are enabled. This prevents errors when the Mbed TLS NV Seed feature is
being used on platforms that have PSA enabled by default, but not Experimental
API support by default.
[DEBUG] Output: compilation terminated.
[ERROR] In file included from ./mbed-os/connectivity/mbedtls/include/mbedtls/config.h:31,
from ./mbed-os/connectivity/mbedtls/include/mbedtls/entropy.h:28,
./mbed-os/connectivity/mbedtls/platform/inc/platform_mbed.h:26:10: fatal error: default_random_seed.h: No such file or directory
26 | #include "default_random_seed.h"
Add license identifier to files which Arm owns the copyright to,
and contain either BSD-3 or Apache-2.0 licenses. This is to address
license errors raised by scancode analysis.
Lingkai Dong
Jaeden Amero
Harrison Mutai
George Psimenos