tree 5a8e72a59f2ef44eb01c66c2e0c55d81d72d2f31
parent 86c2b854b0442ebbe4b28682c15cf3a8beddeec4
author David Benjamin <davidben@google.com> 1510617496 +0800
committer Adam Langley <agl@google.com> 1511391124 +0000

Use some of the word-based functions for ECDSA verification.

This is only a hair faster than the signing change, but still something.
I kept the call to BN_mod_inverse_odd as that appears to be faster
(constant time is not a concern for verification).

Before:
Did 22855 ECDSA P-224 verify operations in 3015099us (7580.2 ops/sec)
Did 21276 ECDSA P-256 verify operations in 3083284us (6900.4 ops/sec)
Did 2635 ECDSA P-384 verify operations in 3032582us (868.9 ops/sec)
Did 1240 ECDSA P-521 verify operations in 3068631us (404.1 ops/sec)

After:
Did 23310 ECDSA P-224 verify operations in 3056226us (7627.1 ops/sec)
Did 21210 ECDSA P-256 verify operations in 3035765us (6986.7 ops/sec)
Did 2666 ECDSA P-384 verify operations in 3023592us (881.7 ops/sec)
Did 1209 ECDSA P-521 verify operations in 3054040us (395.9 ops/sec)

Change-Id: Iec995b1a959dbc83049d0f05bdc525c14a95c28e
Reviewed-on: https://boringssl-review.googlesource.com/23077
Reviewed-by: Adam Langley <agl@google.com>