Coverage Report

Created: 2023-09-23 17:42

/libfido2/openbsd-compat/explicit_bzero.c
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/* OPENBSD ORIGINAL: lib/libc/string/explicit_bzero.c */
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/*      $OpenBSD: explicit_bzero.c,v 1.1 2014/01/22 21:06:45 tedu Exp $ */
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/*
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 * Public domain.
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 * Written by Ted Unangst
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 */
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#include "openbsd-compat.h"
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#if !defined(HAVE_EXPLICIT_BZERO) && !defined(_WIN32)
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#include <string.h>
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/*
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 * explicit_bzero - don't let the compiler optimize away bzero
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 */
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#ifdef HAVE_MEMSET_S
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void
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explicit_bzero(void *p, size_t n)
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{
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        if (n == 0)
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                return;
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        (void)memset_s(p, n, 0, n);
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}
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#else /* HAVE_MEMSET_S */
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/*
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 * Indirect bzero through a volatile pointer to hopefully avoid
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 * dead-store optimisation eliminating the call.
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 */
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static void (* volatile ssh_bzero)(void *, size_t) = bzero;
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void
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explicit_bzero(void *p, size_t n)
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2.91M
{
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2.91M
        if (n == 0)
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                return;
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        /*
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         * clang -fsanitize=memory needs to intercept memset-like functions
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         * to correctly detect memory initialisation. Make sure one is called
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         * directly since our indirection trick above successfully confuses it.
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         */
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2.91M
#if defined(__has_feature)
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# if __has_feature(memory_sanitizer)
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        memset(p, 0, n);
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# endif
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2.91M
#endif
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2.91M
        ssh_bzero(p, n);
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2.91M
}
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#endif /* HAVE_MEMSET_S */
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#endif /* !defined(HAVE_EXPLICIT_BZERO) && !defined(_WIN32) */