1 /*
2 * cchmac_final.c
3 * corecrypto
4 *
5 * Created on 12/07/2010
6 *
7 * Copyright (c) 2010,2011,2015 Apple Inc. All rights reserved.
8 *
9 *
10 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
11 *
12 * This file contains Original Code and/or Modifications of Original Code
13 * as defined in and that are subject to the Apple Public Source License
14 * Version 2.0 (the 'License'). You may not use this file except in
15 * compliance with the License. The rights granted to you under the License
16 * may not be used to create, or enable the creation or redistribution of,
17 * unlawful or unlicensed copies of an Apple operating system, or to
18 * circumvent, violate, or enable the circumvention or violation of, any
19 * terms of an Apple operating system software license agreement.
20 *
21 * Please obtain a copy of the License at
22 * http://www.opensource.apple.com/apsl/ and read it before using this file.
23 *
24 * The Original Code and all software distributed under the License are
25 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
26 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
27 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
28 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
29 * Please see the License for the specific language governing rights and
30 * limitations under the License.
31 *
32 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
33 */
34
35 #include <corecrypto/ccdigest_priv.h>
36 #include <corecrypto/cchmac.h>
37 #include <corecrypto/ccn.h>
38 #include <corecrypto/cc_priv.h>
39
40 void
cchmac_final(const struct ccdigest_info * di,cchmac_ctx_t hc,unsigned char * mac)41 cchmac_final(const struct ccdigest_info *di, cchmac_ctx_t hc,
42 unsigned char *mac)
43 {
44 // Finalize the inner state of the data being HMAC'd, i.e., H((key \oplus ipad) || m)
45 ccdigest_final(di, cchmac_digest_ctx(di, hc), cchmac_data(di, hc));
46
47 // Set the HMAC output size based on the digest algorithm
48 cchmac_num(di, hc) = (unsigned int)di->output_size; /* typecast: output size will alwys fit in an unsigned int */
49 cchmac_nbits(di, hc) = di->block_size * 8;
50
51 // Copy the pre-computed compress(key \oplus opad) back to digest state,
52 // and then run through the digest once more to finish the HMAC
53 ccdigest_copy_state(di, cchmac_istate32(di, hc), cchmac_ostate32(di, hc));
54 ccdigest_final(di, cchmac_digest_ctx(di, hc), mac);
55 }
56