use freezero() instead of memset/explicit_bzero + free. Substantially

reduces conditional logic (-218, +82).

MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH cache alignment calculation bn/bn_exp.c
wasn'tt quite right.  Two other tricky bits with ASN1_STRING_FLAG_NDEF and
BN_FLG_STATIC_DATA where the condition cannot be collapsed completely.

Passes regress.  ok beck

1 files changed, 2 insertions, 5 deletions

diff --git a/src/lib/libcrypto/ecdsa/ecs_vrf.c b/src/lib/libcrypto/ecdsa/ecs_vrf.c
index a4b627ace6..270af94c0d 100644
--- a/src/lib/libcrypto/ecdsa/ecs_vrf.c
+++ b/src/lib/libcrypto/ecdsa/ecs_vrf.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ecs_vrf.c,v 1.5 2015/02/08 13:35:07 jsing Exp $ */
+/* $OpenBSD: ecs_vrf.c,v 1.6 2017/05/02 03:59:44 deraadt Exp $ */
 /*
  * Written by Nils Larsch for the OpenSSL project
  */
@@ -107,10 +107,7 @@ ECDSA_verify(int type, const unsigned char *dgst, int dgst_len,
         ret = ECDSA_do_verify(dgst, dgst_len, s, eckey);
 
 err:
-        if (derlen > 0) {
-                explicit_bzero(der, derlen);
-                free(der);
-        }
+        freezero(der, derlen);
         ECDSA_SIG_free(s);
         return (ret);
 }