| /* OPENBSD ORIGINAL: lib/libc/string/explicit_bzero.c */ |
| /* $OpenBSD: explicit_bzero.c,v 1.1 2014/01/22 21:06:45 tedu Exp $ */ |
| /* |
| * Public domain. |
| * Written by Ted Unangst |
| */ |
| |
| #include "includes.h" |
| |
| #include <string.h> |
| |
| /* |
| * explicit_bzero - don't let the compiler optimize away bzero |
| */ |
| |
| #ifndef HAVE_EXPLICIT_BZERO |
| |
| #ifdef HAVE_MEMSET_S |
| |
| void |
| explicit_bzero(void *p, size_t n) |
| { |
| if (n == 0) |
| return; |
| (void)memset_s(p, n, 0, n); |
| } |
| |
| #else /* HAVE_MEMSET_S */ |
| |
| /* |
| * Indirect bzero through a volatile pointer to hopefully avoid |
| * dead-store optimisation eliminating the call. |
| */ |
| static void (* volatile ssh_bzero)(void *, size_t) = bzero; |
| |
| void |
| explicit_bzero(void *p, size_t n) |
| { |
| if (n == 0) |
| return; |
| /* |
| * clang -fsanitize=memory needs to intercept memset-like functions |
| * to correctly detect memory initialisation. Make sure one is called |
| * directly since our indirection trick above sucessfully confuses it. |
| */ |
| #if defined(__has_feature) |
| # if __has_feature(memory_sanitizer) |
| memset(p, 0, n); |
| # endif |
| #endif |
| |
| ssh_bzero(p, n); |
| } |
| |
| #endif /* HAVE_MEMSET_S */ |
| |
| #endif /* HAVE_EXPLICIT_BZERO */ |