tree f52ba72c8ac02501cb35db7eb33c83c32098fa55
parent fd68d7552badb62bcb0c7e06201589ebd7ee2054
author David Benjamin <davidben@google.com> 1612134247 -0500
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> 1614293033 +0000

Add ECDSA nonce-testing functions.

There are a few places where it is useful to run ECDSA with a specified
nonce:

- An ECDSA KAT in the module self-check

- Unit tests for particular test vectors

- Fuzzing the implementation (requested by the cryptofuzz project)

This replaces the fixed_k machinery with a separate function. Although
they are effectively the same, I've used two different functions.
One is internal and only used in the module self-check. The other is
exported for unit tests and cryptofuzz but marked with a for_testing.
(Chromium's presubmits flag uses of "for_testing" functions outside of
unit tests. The KAT version isn't in a test per se, so it's a separate
function.)

Bug: 391
Change-Id: I0f764d89bf0ac2081307e1079623d508fb0f2df7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/45867
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>