examples/example_decrypt.cpp

   1 /******************************************************************************/
   2 /* SlunkCrypt, by LoRd_MuldeR <MuldeR2@GMX.de>                                */
   3 /* This work has been released under the CC0 1.0 Universal license!           */
   4 /******************************************************************************/
   5
   6 //SlunkCrypt API
   7 #include <slunkcrypt.hpp>
   8
   9 //CRT
  10 #include <cstdlib>
  11 #include <iostream>
  12 #include <fstream>
  13
  14 //Example password
  15 static std::string EXAMPLE_PASSWORD("cMRe5E5D)'!2?5]QDlCQ4tBb");
  16
  17 //Const
  18 #define BUFF_SIZE 4096U
  19
  20 static int decrypt_main(int argc, char *argv[])
  21 {
  22         std::cerr << "SlunkCrypt decrypt sample [" << __DATE__ << "]" << std::endl;
  23         std::cerr << "using libSlunkCrypt v" << SLUNKCRYPT_VERSION_MAJOR << '.' << SLUNKCRYPT_VERSION_MINOR << '.' << SLUNKCRYPT_VERSION_PATCH << '\n' << std::endl;
  24
  25         if (argc < 4)
  26         {
  27                 std::cerr << "Usage:\n  decrypt.exe <nonce> <ciphertext.enc> <plaintext.out>\n" << std::endl;
  28                 return -1;
  29         }
  30
  31         const uint64_t nonce = std::strtoull(argv[1], NULL, 16);
  32
  33         // -----------------------------------------------------------
  34         // Open input/output files
  35         // -----------------------------------------------------------
  36
  37         std::ifstream file_src(argv[2], std::ios::binary);
  38         if (!file_src.is_open())
  39         {
  40                 std::cerr << "Error: Failed to open input file for reading!" << std::endl;
  41                 return -1;
  42         }
  43
  44         std::ofstream file_dst(argv[3], std::ios::binary);
  45         if (!file_dst.is_open())
  46         {
  47                 std::cerr << "Error: Failed to open output file for writing!" << std::endl;
  48                 return -1;
  49         }
  50
  51         // -----------------------------------------------------------
  52         // Initialize the SlunkCryptDecr instance
  53         // -----------------------------------------------------------
  54
  55         std::cerr << "Initializing key, please wait... " << std::flush;
  56
  57         uint8_t buffer[BUFF_SIZE];
  58         slunkcrypt::Decryptor slunk_decrypt(nonce, EXAMPLE_PASSWORD);
  59
  60         std::cerr << "done.\nSlunk-decrypting the file contents, please wait... " << std::flush;
  61
  62         // -----------------------------------------------------------
  63         // Decryption loop
  64         // -----------------------------------------------------------
  65
  66         file_src.exceptions(std::ifstream::badbit);
  67         file_dst.exceptions(std::ifstream::failbit | std::ifstream::badbit);;
  68
  69         try
  70         {
  71                 while (file_src.good())
  72                 {
  73                         file_src.read(reinterpret_cast<char*>(buffer), BUFF_SIZE);
  74                         const std::streamsize count = file_src.gcount();
  75                         if (count > 0)
  76                         {
  77                                 if (!slunk_decrypt.inplace(buffer, (size_t)count))
  78                                 {
  79                                         std::cerr << "failed!\n\nError: SlunkCrypt decryption has failed!" << std::endl;
  80                                         return -1;
  81                                 }
  82                                 file_dst.write(reinterpret_cast<char*>(buffer), count);
  83                         }
  84                 }
  85         }
  86         catch (std::ios_base::failure e)
  87         {
  88                 std::cerr << "failed!\n\nI/O Error: \"" << e.code().message() << "\" [Code: " << e.code().value() << "]\n" << std::endl;
  89                 return -1;
  90         }
  91
  92         // -----------------------------------------------------------
  93         // Clean up
  94         // -----------------------------------------------------------
  95
  96         std::cerr << "done.\n\nCompleted.\n" << std::endl;
  97
  98         file_src.close();
  99         file_dst.close();
 100
 101         return 0;
 102 }
 103
 104 int main(int argc, char *argv[])
 105 {
 106         try
 107         {
 108                 return decrypt_main(argc, argv);
 109         }
 110         catch (std::exception e)
 111         {
 112                 std::cerr << "\n\nException: \"" << e.what() << "\"\n" << std::endl;
 113                 return -1;
 114         }
 115 }