hmac: Add HMAC to 2lib library

This patch adds HMAC. HMAC will be used to sign/verify NVM structures.
Hash algorithms can be selected from those supported
by enum vb2_hash_algorithm (i.e. SHA1, SHA256, or SHA512).

BUG=chrome-os-partner:51907
BRANCH=tot
TEST=make runtests

Change-Id: I6d349bc807874fe2a5512aabcd7fbf67a4eaa40a
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/342880
Reviewed-by: Randall Spangler <rspangler@chromium.org>

1 files changed, 29 insertions, 0 deletions

diff --git a/firmware/2lib/include/2hmac.h b/firmware/2lib/include/2hmac.h
new file mode 100644
index 00000000..1df19397
--- /dev/null
+++ b/firmware/2lib/include/2hmac.h
@@ -0,0 +1,29 @@
+/* Copyright 2016 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.
+ */
+
+#ifndef VBOOT_REFERENCE_VBOOT_2HMAC_H_
+#define VBOOT_REFERENCE_VBOOT_2HMAC_H_
+
+#include <stdint.h>
+#include "2crypto.h"
+
+/**
+ * Compute HMAC
+ *
+ * @param alg		Hash algorithm ID
+ * @param key		HMAC key
+ * @param key_size	HMAC key size
+ * @param msg		Message to compute HMAC for
+ * @param msg_size	Message size
+ * @param mac		Computed message authentication code
+ * @param mac_size	Size of the buffer pointed by <mac>
+ * @return
+ */
+int hmac(enum vb2_hash_algorithm alg,
+	 const void *key, uint32_t key_size,
+	 const void *msg, uint32_t msg_size,
+	 uint8_t *mac, uint32_t mac_size);
+
+#endif