1 /*
2 * Copyright (c) 2016, The OpenThread Authors.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. Neither the name of the copyright holder nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /**
30 * @file
31 * This file implements HMAC SHA-256.
32 */
33
34 #include "hmac_sha256.hpp"
35
36 #include "common/message.hpp"
37
38 namespace ot {
39 namespace Crypto {
40
HmacSha256(void)41 HmacSha256::HmacSha256(void)
42 {
43 const mbedtls_md_info_t *mdInfo = nullptr;
44 mbedtls_md_init(&mContext);
45 mdInfo = mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
46 mbedtls_md_setup(&mContext, mdInfo, 1);
47 }
48
~HmacSha256(void)49 HmacSha256::~HmacSha256(void)
50 {
51 mbedtls_md_free(&mContext);
52 }
53
Start(const uint8_t * aKey,uint16_t aKeyLength)54 void HmacSha256::Start(const uint8_t *aKey, uint16_t aKeyLength)
55 {
56 mbedtls_md_hmac_starts(&mContext, aKey, aKeyLength);
57 }
58
Update(const void * aBuf,uint16_t aBufLength)59 void HmacSha256::Update(const void *aBuf, uint16_t aBufLength)
60 {
61 mbedtls_md_hmac_update(&mContext, reinterpret_cast<const uint8_t *>(aBuf), aBufLength);
62 }
63
Update(const Message & aMessage,uint16_t aOffset,uint16_t aLength)64 void HmacSha256::Update(const Message &aMessage, uint16_t aOffset, uint16_t aLength)
65 {
66 Message::Chunk chunk;
67
68 aMessage.GetFirstChunk(aOffset, aLength, chunk);
69
70 while (chunk.GetLength() > 0)
71 {
72 Update(chunk.GetData(), chunk.GetLength());
73 aMessage.GetNextChunk(aLength, chunk);
74 }
75 }
76
Finish(Hash & aHash)77 void HmacSha256::Finish(Hash &aHash)
78 {
79 mbedtls_md_hmac_finish(&mContext, aHash.m8);
80 }
81
82 } // namespace Crypto
83 } // namespace ot
84
