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-rw-r--r--lib/util/memset_s.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/lib/util/memset_s.c b/lib/util/memset_s.c
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+/*
+ * Copyright (c) 2013-2014 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * This is an open source non-commercial project. Dear PVS-Studio, please check it.
+ * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <errno.h>
+#include <limits.h>
+#if defined(HAVE_STDINT_H)
+# include <stdint.h>
+#elif defined(HAVE_INTTYPES_H)
+# include <inttypes.h>
+#endif
+
+#include "sudo_compat.h"
+
+#ifndef RSIZE_MAX
+# if defined(SIZE_MAX)
+# define RSIZE_MAX (SIZE_MAX >> 1)
+# elif defined(__LP64__)
+# define RSIZE_MAX 0x7fffffffffffffffUL
+# else
+# define RSIZE_MAX 0x7fffffffU
+# endif
+#endif
+
+/*
+ * Simple implementation of C11 memset_s() function.
+ * We use a volatile pointer when updating the byte string.
+ * Most compilers will avoid optimizing away access to a
+ * volatile pointer, even if the pointer appears to be unused
+ * after the call.
+ *
+ * Note that C11 does not specify the return value on error, only
+ * that it be non-zero. We use EINVAL for all errors.
+ */
+errno_t
+sudo_memset_s(void *v, rsize_t smax, int c, rsize_t n)
+{
+ errno_t ret = 0;
+ volatile unsigned char *s = v;
+
+ /* Fatal runtime-constraint violations. */
+ if (s == NULL || smax > RSIZE_MAX) {
+ ret = errno = EINVAL;
+ goto done;
+ }
+ /* Non-fatal runtime-constraint violation, n must not exceed smax. */
+ if (n > smax) {
+ n = smax;
+ ret = errno = EINVAL;
+ }
+ /* Updating through a volatile pointer should not be optimized away. */
+ while (n--)
+ *s++ = (unsigned char)c;
+done:
+ return ret;
+}