nistp521: add a comment to the P+P exceptional case in point_add.
authorAdam Langley <agl@google.com>
Tue, 26 Sep 2017 17:48:55 +0000 (10:48 -0700)
committerRich Salz <rsalz@openssl.org>
Mon, 2 Oct 2017 15:30:30 +0000 (11:30 -0400)
commit2dbfa8444bdf7669a54006c4a83d1e60ba374528
tree03ba37346c5bf1f7ca394ebc0741a1a059af6344
parentc55b786a8911cef41f890735ba5fde79e116e055
nistp521: add a comment to the P+P exceptional case in point_add.

This change adds a comment to the exceptional case in point_add that
handles the case of a doubling, which explains when this case may occur
during normal processing.

Thanks go to Antonio Sanso for noting this.

Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4424)
crypto/ec/ecp_nistp521.c