tree 070dd2775f02eebbb86d84d798b377729d698a79
parent c4e4757b636b1765a322b76406e6d472e60b5f01
author David Benjamin <davidben@google.com> 1520143100 -0500
committer Adam Langley <alangley@gmail.com> 1522439640 +0000

Make RSA_check_key constant-time and more meaningful.

Rather than recompute values the same as in key generation, where
possible, we check differently. In particular, most RSA values are
modular inverses of some value. Check each of them by multiplying and
using our naive constant-time division function.

Median of 29 RSA keygens: 0m0.218s -> 0m0.205s
(Accuracy beyond 0.1s is questionable.)

Bug: 238
Change-Id: Iaca19f12c045457013def844a17bf502ed09136e
Reviewed-on: https://boringssl-review.googlesource.com/26373
Reviewed-by: Adam Langley <alangley@gmail.com>