1 // Copyright (c) 2014-2018 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5 #include <crypto/hmac_sha256.h>
6
7 #include <string.h>
8
CHMAC_SHA256(const unsigned char * key,size_t keylen)9 CHMAC_SHA256::CHMAC_SHA256(const unsigned char* key, size_t keylen)
10 {
11 unsigned char rkey[64];
12 if (keylen <= 64) {
13 memcpy(rkey, key, keylen);
14 memset(rkey + keylen, 0, 64 - keylen);
15 } else {
16 CSHA256().Write(key, keylen).Finalize(rkey);
17 memset(rkey + 32, 0, 32);
18 }
19
20 for (int n = 0; n < 64; n++)
21 rkey[n] ^= 0x5c;
22 outer.Write(rkey, 64);
23
24 for (int n = 0; n < 64; n++)
25 rkey[n] ^= 0x5c ^ 0x36;
26 inner.Write(rkey, 64);
27 }
28
Finalize(unsigned char hash[OUTPUT_SIZE])29 void CHMAC_SHA256::Finalize(unsigned char hash[OUTPUT_SIZE])
30 {
31 unsigned char temp[32];
32 inner.Finalize(temp);
33 outer.Write(temp, 32).Finalize(hash);
34 }
35