cr50: drop cryptoc for p256 implementationstabilize-14151.B-cr50_stab

To implement FIPS module we need to bring many crypto functions in the
module boundary. Unfortunately, cryptoc is a third-party library used
by dcrypto code in cr50. Cryptoc is also not well-maintained and shared
with other projects. While just making local copy of cryptoc would
solve an issue, it's suboptimal as prevents from many optimizations and
improvements.

Removed redundant functions (dcrypto_p256_pick and dcrypto_p256_rand).

Another improvement is separation of platform independent code in p256.c
to support better host-side unit tests. For this purpose added fast
random number generator using LFSR to replace use of TRNG for blinding
and wiping secrets where security strength is not required.

BUG=b:138578318
TEST=make BOARD=cr50 CRYPTO_TEST=1; test/tpm_test/tpmtest.py
in console: dcrypto_ecdsa

Signed-off-by: Vadim Sukhomlinov <sukhomlinov@google.com>
Change-Id: I9bfd13b8006ddca55508635962be4502a56532b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3087833
Reviewed-by: Vadim Sukhomlinov <sukhomlinov@chromium.org>
Reviewed-by: Andrey Pronin <apronin@chromium.org>
Tested-by: Vadim Sukhomlinov <sukhomlinov@chromium.org>
Commit-Queue: Vadim Sukhomlinov <sukhomlinov@chromium.org>

0 files changed, 0 insertions, 0 deletions