C++ (Cpp) secure_vector::insertの例

コード例 #1

ファイル: ccm.cpp プロジェクト: Andrew-He/botan

void CCM_Decryption::finish(secure_vector<byte>& buffer, size_t offset)
   {
   BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");

   buffer.insert(buffer.begin() + offset, msg_buf().begin(), msg_buf().end());

   const size_t sz = buffer.size() - offset;
   byte* buf = buffer.data() + offset;

   BOTAN_ASSERT(sz >= tag_size(), "We have the tag");

   const secure_vector<byte>& ad = ad_buf();
   BOTAN_ASSERT(ad.size() % BS == 0, "AD is block size multiple");

   const BlockCipher& E = cipher();

   secure_vector<byte> T(BS);
   E.encrypt(format_b0(sz - tag_size()), T);

   for(size_t i = 0; i != ad.size(); i += BS)
      {
      xor_buf(T.data(), &ad[i], BS);
      E.encrypt(T);
      }

   secure_vector<byte> C = format_c0();

   secure_vector<byte> S0(BS);
   E.encrypt(C, S0);
   inc(C);

   secure_vector<byte> X(BS);

   const byte* buf_end = &buf[sz - tag_size()];

   while(buf != buf_end)
      {
      const size_t to_proc = std::min<size_t>(BS, buf_end - buf);

      E.encrypt(C, X);
      xor_buf(buf, X.data(), to_proc);
      inc(C);

      xor_buf(T.data(), buf, to_proc);
      E.encrypt(T);

      buf += to_proc;
      }

   T ^= S0;

   if(!same_mem(T.data(), buf_end, tag_size()))
      throw Integrity_Failure("CCM tag check failed");

   buffer.resize(buffer.size() - tag_size());
   }

コード例 #2

ファイル: ccm.cpp プロジェクト: Andrew-He/botan

void CCM_Encryption::finish(secure_vector<byte>& buffer, size_t offset)
   {
   BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");

   buffer.insert(buffer.begin() + offset, msg_buf().begin(), msg_buf().end());

   const size_t sz = buffer.size() - offset;
   byte* buf = buffer.data() + offset;

   const secure_vector<byte>& ad = ad_buf();
   BOTAN_ASSERT(ad.size() % BS == 0, "AD is block size multiple");

   const BlockCipher& E = cipher();

   secure_vector<byte> T(BS);
   E.encrypt(format_b0(sz), T);

   for(size_t i = 0; i != ad.size(); i += BS)
      {
      xor_buf(T.data(), &ad[i], BS);
      E.encrypt(T);
      }

   secure_vector<byte> C = format_c0();
   secure_vector<byte> S0(BS);
   E.encrypt(C, S0);
   inc(C);

   secure_vector<byte> X(BS);

   const byte* buf_end = &buf[sz];

   while(buf != buf_end)
      {
      const size_t to_proc = std::min<size_t>(BS, buf_end - buf);

      xor_buf(T.data(), buf, to_proc);
      E.encrypt(T);

      E.encrypt(C, X);
      xor_buf(buf, X.data(), to_proc);
      inc(C);

      buf += to_proc;
      }

   T ^= S0;

   buffer += std::make_pair(T.data(), tag_size());
   }