(Imported from upstream's 64333004a41a9f4aa587b8e5401420fb70d00687.)
RT#4284.
This case should be impossible to hit because |EC_POINT_add| doesn't use
this function and trying to add equal inputs should never occur during a
multiplication. Support for this exists because the pattern has been
copied from the first 64-bit P-224 and P-256 work that Emilia, Bodo and
I did. There it seemed like a reasonable defense-in-depth in case the
code changed in the future.
Change-Id: I7ff138669c5468b7d7a5153429bec728cb67e338
Reviewed-on: https://boringssl-review.googlesource.com/7246
Reviewed-by: David Benjamin <davidben@google.com>
This change incorporates Intel's P-256 implementation. The record of
Intel's submission under CLA is in internal bug number 25330687.
Before:
Did 3582 ECDH P-256 operations in 1049114us (3414.3 ops/sec)
Did 8525 ECDSA P-256 signing operations in 1028778us (8286.5 ops/sec)
Did 3487 ECDSA P-256 verify operations in 1008996us (3455.9 ops/sec)
build/tool/bssl is 1434704 bytes after strip -s
After:
Did 8618 ECDH P-256 operations in 1027884us (8384.2 ops/sec)
Did 21000 ECDSA P-256 signing operations in 1049490us (20009.7 ops/sec)
Did 8268 ECDSA P-256 verify operations in 1079481us (7659.2 ops/sec)
build/tool/bssl is 1567216 bytes after strip -s
Change-Id: I147971a8e19849779c8ed7e20310d41bd4962299
Reviewed-on: https://boringssl-review.googlesource.com/6371
Reviewed-by: Adam Langley <agl@google.com>