/libfido2/openbsd-compat/explicit_bzero.c
| Line | Count | Source | 
| 1 |  | /* OPENBSD ORIGINAL: lib/libc/string/explicit_bzero.c */ | 
| 2 |  | /*      $OpenBSD: explicit_bzero.c,v 1.1 2014/01/22 21:06:45 tedu Exp $ */ | 
| 3 |  | /* | 
| 4 |  |  * Public domain. | 
| 5 |  |  * Written by Ted Unangst | 
| 6 |  |  */ | 
| 7 |  |  | 
| 8 |  | #include "openbsd-compat.h" | 
| 9 |  |  | 
| 10 |  | #if !defined(HAVE_EXPLICIT_BZERO) && !defined(_WIN32) | 
| 11 |  |  | 
| 12 |  | #include <string.h> | 
| 13 |  |  | 
| 14 |  | /* | 
| 15 |  |  * explicit_bzero - don't let the compiler optimize away bzero | 
| 16 |  |  */ | 
| 17 |  |  | 
| 18 |  | #ifdef HAVE_MEMSET_S | 
| 19 |  |  | 
| 20 |  | void | 
| 21 |  | explicit_bzero(void *p, size_t n) | 
| 22 |  | { | 
| 23 |  |         if (n == 0) | 
| 24 |  |                 return; | 
| 25 |  |         (void)memset_s(p, n, 0, n); | 
| 26 |  | } | 
| 27 |  |  | 
| 28 |  | #else /* HAVE_MEMSET_S */ | 
| 29 |  |  | 
| 30 |  | /* | 
| 31 |  |  * Indirect bzero through a volatile pointer to hopefully avoid | 
| 32 |  |  * dead-store optimisation eliminating the call. | 
| 33 |  |  */ | 
| 34 |  | static void (* volatile ssh_bzero)(void *, size_t) = bzero; | 
| 35 |  |  | 
| 36 |  | void | 
| 37 |  | explicit_bzero(void *p, size_t n) | 
| 38 | 15.0M | { | 
| 39 | 15.0M |         if (n == 0) | 
| 40 | 1.01k |                 return; | 
| 41 |  |         /* | 
| 42 |  |          * clang -fsanitize=memory needs to intercept memset-like functions | 
| 43 |  |          * to correctly detect memory initialisation. Make sure one is called | 
| 44 |  |          * directly since our indirection trick above successfully confuses it. | 
| 45 |  |          */ | 
| 46 | 15.0M | #if defined(__has_feature) | 
| 47 |  | # if __has_feature(memory_sanitizer) | 
| 48 |  |         memset(p, 0, n); | 
| 49 |  | # endif | 
| 50 | 15.0M | #endif | 
| 51 |  |  | 
| 52 | 15.0M |         ssh_bzero(p, n); | 
| 53 | 15.0M | } | 
| 54 |  |  | 
| 55 |  | #endif /* HAVE_MEMSET_S */ | 
| 56 |  |  | 
| 57 |  | #endif /* !defined(HAVE_EXPLICIT_BZERO) && !defined(_WIN32) */ |