RSA signature verification and SHA-1/256/512 reference implementation for verified boot.

Also contains some preliminary tests for these primitives.

Review URL: http://codereview.chromium.org/553023

include/utility.h

@@ -0,0 +1,32 @@
+/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* Helper functions/wrappers for memory allocations, manipulation and
+ * comparison.
+ */
+
+#ifndef VBOOT_REFERENCE_UTILITY_H_
+#define VBOOT_REFERENCE_UTILITY_H_
+
+#include <string.h>
+
+/* Allocate [size] bytes and return a pointer to the allocated memory. Abort
+ * on error.
+ */
+void* Malloc(size_t size);
+
+/* Free memory pointed by [ptr] previously allocated by Malloc(). */
+void Free(void* ptr);
+
+/* Copy [n] bytes from [src] to [dest]. */
+void* Memcpy(void* dest, const void* src, size_t n);
+
+/* Compare [n] bytes starting at [s1] with [s2] and return 1 if they match,
+ * 0 if they don't. Time taken to perform the comparison is only dependent on
+ * [n] and not on the relationship of the match between [s1] and [s2].
+ */
+int SafeMemcmp(const void* s1, const void* s2, size_t n);
+
+#endif  /* VBOOT_REFERENCE_UTILITY_H_ */