1263635Sdes/* OPENBSD ORIGINAL: lib/libc/string/explicit_bzero.c */
2263635Sdes/*	$OpenBSD: explicit_bzero.c,v 1.1 2014/01/22 21:06:45 tedu Exp $ */
3263635Sdes/*
4263635Sdes * Public domain.
5263635Sdes * Written by Ted Unangst
6263635Sdes */
7263635Sdes
8263635Sdes#include "includes.h"
9263635Sdes
10295367Sdes/*
11295367Sdes * explicit_bzero - don't let the compiler optimize away bzero
12295367Sdes */
13295367Sdes
14263635Sdes#ifndef HAVE_EXPLICIT_BZERO
15263635Sdes
16295367Sdes#ifdef HAVE_MEMSET_S
17295367Sdes
18295367Sdesvoid
19295367Sdesexplicit_bzero(void *p, size_t n)
20295367Sdes{
21295367Sdes	(void)memset_s(p, n, 0, n);
22295367Sdes}
23295367Sdes
24295367Sdes#else /* HAVE_MEMSET_S */
25295367Sdes
26263635Sdes/*
27295367Sdes * Indirect bzero through a volatile pointer to hopefully avoid
28295367Sdes * dead-store optimisation eliminating the call.
29263635Sdes */
30295367Sdesstatic void (* volatile ssh_bzero)(void *, size_t) = bzero;
31295367Sdes
32263635Sdesvoid
33263635Sdesexplicit_bzero(void *p, size_t n)
34263635Sdes{
35295367Sdes	ssh_bzero(p, n);
36263635Sdes}
37295367Sdes
38295367Sdes#endif /* HAVE_MEMSET_S */
39295367Sdes
40295367Sdes#endif /* HAVE_EXPLICIT_BZERO */
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