Line data    Source code

       1             : /*************************************************************************
       2             :  *
       3             :  *  Project
       4             :  *                         _____ _____  __  __ _____
       5             :  *                        / ____|  __ \|  \/  |  __ \
       6             :  *  ___  _ __   ___ _ __ | |  __| |__) | \  / | |__) |
       7             :  * / _ \| '_ \ / _ \ '_ \| | |_ |  ___/| |\/| |  ___/
       8             :  *| (_) | |_) |  __/ | | | |__| | |    | |  | | |
       9             :  * \___/| .__/ \___|_| |_|\_____|_|    |_|  |_|_|
      10             :  *      | |
      11             :  *      |_|
      12             :  *
      13             :  * Copyright (C) Akiel Aries, <akiel@akiel.org>, et al.
      14             :  *
      15             :  * This software is licensed as described in the file LICENSE, which
      16             :  * you should have received as part of this distribution. The terms
      17             :  * among other details are referenced in the official documentation
      18             :  * seen here : https://akielaries.github.io/openGPMP/ along with
      19             :  * important files seen in this project.
      20             :  *
      21             :  * You may opt to use, copy, modify, merge, publish, distribute
      22             :  * and/or sell copies of the Software, and permit persons to whom
      23             :  * the Software is furnished to do so, under the terms of the
      24             :  * LICENSE file. As this is an Open Source effort, all implementations
      25             :  * must be of the same methodology.
      26             :  *
      27             :  *
      28             :  *
      29             :  * This software is distributed on an AS IS basis, WITHOUT
      30             :  * WARRANTY OF ANY KIND, either express or implied.
      31             :  *
      32             :  ************************************************************************/
      33             : 
      34             : /*
      35             :  * This file shows the implementation of some basic stream cipher
      36             :  * algorithms
      37             :  */
      38             : #include <cmath>
      39             : #include <cstdlib>
      40             : #include <iostream>
      41             : #include <openGPMP/nt/cipher.hpp>
      42             : #include <sstream>
      43             : #include <stdio.h>
      44             : #include <string>
      45             : 
      46           3 : std::string gpmp::Cipher::caesar(std::string plaintext, int64_t key) {
      47           3 :     std::string hashtext = "";
      48             : 
      49          36 :     for (int64_t i = 0; uint64_t(i) < plaintext.length(); i++) {
      50             :         // inject transformation
      51          33 :         if (isupper(plaintext[i])) {
      52             :             // upper case
      53          20 :             hashtext += char(int64_t(plaintext[i] + key - 65) % 26 + 65);
      54             :         } else {
      55             :             // lower case
      56          13 :             hashtext += char(int64_t(plaintext[i] + key - 97) % 26 + 97);
      57             :         }
      58             :     }
      59             : 
      60           3 :     return hashtext;
      61           0 : }
      62             : 
      63           3 : std::string gpmp::Cipher::keyword_encode(std::string key) {
      64           3 :     std::string encoded = "";
      65             :     // This array represents the 26 letters of alphabets
      66           3 :     bool arr[26] = {0};
      67             : 
      68             :     // This loop inserts the keyword at the start of the encoded
      69             :     // string
      70          25 :     for (int64_t i = 0; uint64_t(i) < key.size(); i++) {
      71          22 :         if (key[i] >= 'A' && key[i] <= 'Z') {
      72             :             /*
      73             :              * To check whether the character is inserted earlier
      74             :              * in the encoded string or not
      75             :              */
      76           5 :             if (arr[key[i] - 65] == 0) {
      77           5 :                 encoded += key[i];
      78           5 :                 arr[key[i] - 65] = 1;
      79             :             }
      80          17 :         } else if (key[i] >= 'a' && key[i] <= 'z') {
      81          15 :             if (arr[key[i] - 97] == 0) {
      82          14 :                 encoded += key[i] - 32;
      83          14 :                 arr[key[i] - 97] = 1;
      84             :             }
      85             :         }
      86             :     }
      87             : 
      88             :     // This loop inserts the remaining characters in the encoded
      89             :     // string.
      90          81 :     for (int64_t i = 0; i < 26; i++) {
      91          78 :         if (arr[i] == 0) {
      92          59 :             arr[i] = 1;
      93          59 :             encoded += char(i + 65);
      94             :         }
      95             :     }
      96           6 :     return encoded;
      97           0 : }
      98             : 
      99           3 : std::string gpmp::Cipher::keyword(std::string plaintext,
     100             :                                   std::string encoded_text) {
     101           3 :     std::string cipher = "";
     102             : 
     103             :     /*
     104             :      * This loop ciphered the message. Spaces, special characters
     105             :      * and numbers remain same.
     106             :      */
     107          27 :     for (int64_t i = 0; uint64_t(i) < plaintext.size(); i++) {
     108          24 :         if (plaintext[i] >= 'a' && plaintext[i] <= 'z') {
     109          14 :             int64_t pos = plaintext[i] - 97;
     110          14 :             cipher += encoded_text[pos];
     111             :         }
     112             : 
     113          10 :         else if (plaintext[i] >= 'A' && plaintext[i] <= 'Z') {
     114           6 :             int64_t pos = plaintext[i] - 65;
     115           6 :             cipher += encoded_text[pos];
     116             :         }
     117             : 
     118             :         else {
     119           4 :             cipher += plaintext[i];
     120             :         }
     121             :     }
     122           3 :     return cipher;
     123           0 : }