source

#include "hash_function.h"

uint32_t sourceSize = 0;

///@brief Функция для считывания имени файла
///
std::string GetFileName( std::string purposeName )
{
     std::string fileName;
     std::cout << "Enter filename to " << purposeName << ": ";
     std::cin >> fileName;
     std::cin.ignore(32767, '\n');
     return fileName;
}

///@brief Функция для считывания ключа КС
///
uint32_t GetFeistelKey()
{
     std::ifstream fileStream( GetFileName("read key"), std::ios::binary | std::ios::in );
     uint32_t tempKey = 0;
     if ( fileStream.is_open() )
     {
          // Ключ 4 байта - проверим размер файла
          std::streampos fileSize;
          fileSize = fileStream.tellg();
          fileStream.seekg( 0, std::ios::end );
          fileSize = fileStream.tellg() - fileSize;
          fileStream.seekg( 0, std::ios::beg );

          fileStream >> std::noskipws;

          if ( static_cast<uint32_t>(fileSize) != 4 )
          {
               std::cout << "File length cannot be less than 4 bytes" << std::endl;
               return 0;
          }
          else
          {
               for ( size_t i = 0; i < 4; ++i )
               {
                    tempKey += static_cast<uint8_t>( fileStream.get() );
                    if (i != 3)
                         tempKey <<= 8;
               }
          }
     }
     std::cout << "Key: " <<
          ((tempKey >> 24) & 0xFF) << " " << ((tempKey >> 16) & 0xFF) << " " <<
          ((tempKey >> 8) & 0xFF) << " " << (tempKey & 0xFF) << std::endl;
     fileStream.close();

     return tempKey;
}

///@brief Функция для считывания открытого текста
///
std::vector<uint8_t> ReadData( std::string fileName )
{
     std::ifstream fileStream( fileName, std::ios::binary | std::ios::in);
     std::vector<uint8_t> data;

     if ( fileStream )
     {
          fileStream.seekg(0, std::ios::end);
          data.reserve(static_cast<size_t>(fileStream.tellg()));
          sourceSize = fileStream.tellg();
          fileStream.seekg(0, std::ios::beg);
     }
     fileStream >> std::noskipws;

     if ( fileStream.is_open() )
     {
          for ( size_t i = 0; i < data.capacity(); ++i )
          {
               uint8_t tempSym;
               fileStream >> tempSym;
               data.push_back( tempSym );
          }
     }
     fileStream.close();
     return data;
}

///@brief Функция для записи шифртекста
///
void WriteData( std::string fileName, std::vector<uint8_t> result )
{
     std::ofstream fileStream(fileName, std::ios::binary | std::ios::out);
     if (fileStream.is_open())
     {
          for ( const uint8_t& sym : result )
          {
               fileStream << sym;
          }
     }
     fileStream.close();
}


int main()
{
     // Данные КС
     const std::vector<uint8_t> S{ 14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7 };
     uint32_t feistelKey = GetFeistelKey();
     // Объект КС
     CryptoSystem cs( S, feistelKey );

     // Считываем открытый текст
     std::vector<uint8_t> data = ReadData( GetFileName("for source text") );
     uint32_t hash;
     hash = cs.EncryptText( data );

     printf("Size file (L): %d ", sourceSize);
     printf("( %.2X %.2X %.2X %.2X )\n", (uint8_t)(sourceSize >> 24), (uint8_t)(sourceSize >> 16), (uint8_t)(sourceSize >> 8), (uint8_t)(sourceSize));
     printf("Hash: %u ", hash);
     printf("( %.2X %.2X %.2X %.2X )\n", (uint8_t)(hash >> 24), (uint8_t)(hash >> 16), (uint8_t)(hash >> 8), (uint8_t)(hash));


     return 0;
}