/* 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 <string.h> /* * explicit_bzero - don't let the compiler optimize away bzero */ #ifndef HAVE_EXPLICIT_BZERO #include "util.h" #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 successfully 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 */ |