hkdf_sha256_32.cpp raw
1 // Copyright (c) 2018-2019 The Limenka 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/hkdf_sha256_32.h>
6
7 #include <assert.h>
8 #include <string.h>
9
10 CHKDF_HMAC_SHA256_L32::CHKDF_HMAC_SHA256_L32(const unsigned char* ikm, size_t ikmlen, const std::string& salt)
11 {
12 CHMAC_SHA256((const unsigned char*)salt.data(), salt.size()).Write(ikm, ikmlen).Finalize(m_prk);
13 }
14
15 void CHKDF_HMAC_SHA256_L32::Expand32(const std::string& info, unsigned char hash[OUTPUT_SIZE])
16 {
17 // expand a 32byte key (single round)
18 assert(info.size() <= 128);
19 static const unsigned char one[1] = {1};
20 CHMAC_SHA256(m_prk, 32).Write((const unsigned char*)info.data(), info.size()).Write(one, 1).Finalize(hash);
21 }
22