Rough and ready port of axTLS

Revision:
0:5a29fd060ac8
diff -r 000000000000 -r 5a29fd060ac8 crypto/hmac.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/crypto/hmac.c	Mon May 13 18:15:18 2013 +0000
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2007, Cameron Rich
+ * 
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, 
+ *   this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice, 
+ *   this list of conditions and the following disclaimer in the documentation 
+ *   and/or other materials provided with the distribution.
+ * * Neither the name of the axTLS project nor the names of its contributors 
+ *   may be used to endorse or promote products derived from this software 
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * HMAC implementation - This code was originally taken from RFC2104
+ * See http://www.ietf.org/rfc/rfc2104.txt and
+ * http://www.faqs.org/rfcs/rfc2202.html
+ */
+
+#include <string.h>
+#include "os_port.h"
+#include "crypto.h"
+
+/**
+ * Perform HMAC-MD5
+ * NOTE: does not handle keys larger than the block size.
+ */
+void hmac_md5(const uint8_t *msg, int length, const uint8_t *key, 
+        int key_len, uint8_t *digest)
+{
+    MD5_CTX context;
+    uint8_t k_ipad[64];
+    uint8_t k_opad[64];
+    int i;
+
+    memset(k_ipad, 0, sizeof k_ipad);
+    memset(k_opad, 0, sizeof k_opad);
+    memcpy(k_ipad, key, key_len);
+    memcpy(k_opad, key, key_len);
+
+    for (i = 0; i < 64; i++) 
+    {
+        k_ipad[i] ^= 0x36;
+        k_opad[i] ^= 0x5c;
+    }
+
+    MD5_Init(&context);
+    MD5_Update(&context, k_ipad, 64);
+    MD5_Update(&context, msg, length);
+    MD5_Final(digest, &context);
+    MD5_Init(&context);
+    MD5_Update(&context, k_opad, 64);
+    MD5_Update(&context, digest, MD5_SIZE);
+    MD5_Final(digest, &context);
+}
+
+/**
+ * Perform HMAC-SHA1
+ * NOTE: does not handle keys larger than the block size.
+ */
+void hmac_sha1(const uint8_t *msg, int length, const uint8_t *key, 
+        int key_len, uint8_t *digest)
+{
+    SHA1_CTX context;
+    uint8_t k_ipad[64];
+    uint8_t k_opad[64];
+    int i;
+
+    memset(k_ipad, 0, sizeof k_ipad);
+    memset(k_opad, 0, sizeof k_opad);
+    memcpy(k_ipad, key, key_len);
+    memcpy(k_opad, key, key_len);
+
+    for (i = 0; i < 64; i++) 
+    {
+        k_ipad[i] ^= 0x36;
+        k_opad[i] ^= 0x5c;
+    }
+
+    SHA1_Init(&context);
+    SHA1_Update(&context, k_ipad, 64);
+    SHA1_Update(&context, msg, length);
+    SHA1_Final(digest, &context);
+    SHA1_Init(&context);
+    SHA1_Update(&context, k_opad, 64);
+    SHA1_Update(&context, digest, SHA1_SIZE);
+    SHA1_Final(digest, &context);
+}