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51 lines
1.6 KiB
C
51 lines
1.6 KiB
C
/* Erasure of sensitive data, generic implementation.
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Copyright (C) 2016-2020 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public
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License as published by the Free Software Foundation; either
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version 3 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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/* An assembler implementation of explicit_bzero can be created as an
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assembler alias of an optimized bzero implementation.
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Architecture-specific implementations also need to define
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__explicit_bzero_chk. */
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#if !_LIBC
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# include <config.h>
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#endif
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#include <string.h>
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#if _LIBC
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/* glibc-internal users use __explicit_bzero_chk, and explicit_bzero
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redirects to that. */
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# undef explicit_bzero
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#endif
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/* Set LEN bytes of S to 0. The compiler will not delete a call to
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this function, even if S is dead after the call. */
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void
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explicit_bzero (void *s, size_t len)
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{
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#ifdef HAVE_EXPLICIT_MEMSET
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explicit_memset (s, 0, len);
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#else
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memset (s, '\0', len);
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# if defined __GNUC__ && !defined __clang__
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/* Compiler barrier. */
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asm volatile ("" ::: "memory");
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# endif
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#endif
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}
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