/*
* TLS Handshake Hash
* (C) 2004-2006,2011 Jack Lloyd
*
* Released under the terms of the Botan license
*/

#include <botan/internal/tls_handshake_hash.h>
#include <botan/tls_exceptn.h>
#include <botan/md5.h>
#include <botan/sha160.h>
#include <botan/sha2_32.h>
#include <memory>

namespace Botan {

namespace TLS {

void Handshake_Hash::update(Handshake_Type handshake_type,
                                const MemoryRegion<byte>& handshake_msg)
   {
   update(static_cast<byte>(handshake_type));

   const size_t record_length = handshake_msg.size();
   for(size_t i = 0; i != 3; i++)
      update(get_byte<u32bit>(i+1, record_length));

   update(handshake_msg);
   }

/**
* Return a TLS Handshake Hash
*/
SecureVector<byte> Handshake_Hash::final(Protocol_Version version)
   {
   SecureVector<byte> output;

   if(version == Protocol_Version::TLS_V10 || version == Protocol_Version::TLS_V11)
      {
      MD5 md5;
      SHA_160 sha1;

      md5.update(data);
      sha1.update(data);

      output += md5.final();
      output += sha1.final();
      }
   else if(version == Protocol_Version::TLS_V12)
      {
      // This might depend on the ciphersuite
      SHA_256 sha256;
      sha256.update(data);
      output += sha256.final();
      }
   else
      throw TLS_Exception(PROTOCOL_VERSION,
                          "Unknown version for handshake hashes");

   return output;
   }

/**
* Return a SSLv3 Handshake Hash
*/
SecureVector<byte> Handshake_Hash::final_ssl3(const MemoryRegion<byte>& secret)
   {
   const byte PAD_INNER = 0x36, PAD_OUTER = 0x5C;

   MD5 md5;
   SHA_160 sha1;

   md5.update(data);
   sha1.update(data);

   md5.update(secret);
   sha1.update(secret);

   for(size_t i = 0; i != 48; ++i)
      md5.update(PAD_INNER);
   for(size_t i = 0; i != 40; ++i)
      sha1.update(PAD_INNER);

   SecureVector<byte> inner_md5 = md5.final(), inner_sha1 = sha1.final();

   md5.update(secret);
   sha1.update(secret);
   for(size_t i = 0; i != 48; ++i)
      md5.update(PAD_OUTER);
   for(size_t i = 0; i != 40; ++i)
      sha1.update(PAD_OUTER);
   md5.update(inner_md5);
   sha1.update(inner_sha1);

   SecureVector<byte> output;
   output += md5.final();
   output += sha1.final();
   return output;
   }

}

}