1 files changed, 65 insertions, 0 deletions
diff --git a/librecrypt_wipe.c b/librecrypt_wipe.c
new file mode 100644
index 0000000..a704ef0
--- /dev/null
+++ b/librecrypt_wipe.c
@@ -0,0 +1,65 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+#if defined(__GNUC__)
+# pragma GCC diagnostic ignored "-Wsuggest-attribute=const"
+# pragma GCC diagnostic ignored "-Wsuggest-attribute=pure"
+#endif
+
+
+void *(*volatile librecrypt_explicit_memset_____)(void *, int, size_t) = &memset;
+
+
+#if defined(__clang__) /* before __GNUC__ because that is also set in clang */
+# if __has_attribute(optnone)
+__attribute__((optnone))
+# endif
+#elif defined(__GNUC__)
+# if __GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__ >= 40400
+__attribute__((optimize("-O0")))
+# endif
+#endif
+void
+librecrypt_wipe(void *buffer, size_t size)
+{
+	if (buffer && size) {
+		buffer = (*librecrypt_explicit_memset_____)(buffer, 0, size);
+#if defined(__GNUC__)
+		__asm__ volatile ("" :: "g" (buffer) : "memory");
+#else
+		(void) buffer;
+#endif
+	}
+}
+
+
+#else
+
+
+int
+main(void)
+{
+	char *buf;
+
+	SET_UP_ALARM();
+
+#if defined(__GNUC__)
+# pragma GCC diagnostic ignored "-Wnonnull"
+#endif
+
+	librecrypt_wipe(NULL, 0u);
+	librecrypt_wipe(NULL, 4094u);
+	librecrypt_wipe((void *)(intptr_t)-1, 0u);
+
+	buf = malloc(256u);
+	memset(buf, 99, 256u);
+	librecrypt_wipe(buf, 256u);
+	free(buf); /* TODO should test memory is wiped */
+
+	return 0;
+}
+
+
+#endif