hmac_sha256.cpp raw

   1  // Copyright (c) 2014-2018 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/hmac_sha256.h>
   6  
   7  #include <string.h>
   8  
   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  
  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