From fea3943adadf6527d1e839a2953e9591896e628d Mon Sep 17 00:00:00 2001 From: "Maciej S. Szmigiero" Date: Tue, 5 Mar 2019 14:30:22 +0100 Subject: [PATCH] Use explicit_bzero() on recent glibc versions glibc 2.25+ has explicit_bzero(), so we can use it to securely wipe memory instead of hacking our own memset-based replacement, just like we already do on OpenBSD. --- src/core.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/src/core.c b/src/core.c index 8781852..8361175 100644 --- a/src/core.c +++ b/src/core.c @@ -25,6 +25,9 @@ #endif #define VC_GE_2005(version) (version >= 1400) +/* for explicit_bzero() on glibc */ +#define _DEFAULT_SOURCE + #include #include #include @@ -120,12 +123,20 @@ void free_memory(const argon2_context *context, uint8_t *memory, } } +#if defined(__OpenBSD__) +#define HAVE_EXPLICIT_BZERO 1 +#elif defined(__GLIBC__) && defined(__GLIBC_PREREQ) +#if __GLIBC_PREREQ(2,25) +#define HAVE_EXPLICIT_BZERO 1 +#endif +#endif + void NOT_OPTIMIZED secure_wipe_memory(void *v, size_t n) { #if defined(_MSC_VER) && VC_GE_2005(_MSC_VER) SecureZeroMemory(v, n); #elif defined memset_s memset_s(v, n, 0, n); -#elif defined(__OpenBSD__) +#elif defined(HAVE_EXPLICIT_BZERO) explicit_bzero(v, n); #else static void *(*const volatile memset_sec)(void *, int, size_t) = &memset; -- 2.20.1