Stream_Cipher.cpp

//Stream_Cipher
//Naman Garg
//CS458 programming assignment 1

#import <iostream>
#include <stdlib.h>
#include <sstream>
#include <string>
#include <vector>
#include <fstream>

using namespace std;

const int Sr[16][16] = {{0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76},
                        {0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0},
                        {0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15},
                        {0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75},
                        {0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84},
                        {0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF},
                        {0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8},
                        {0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2},
                        {0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73},
                        {0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB},
                        {0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79},
                        {0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08},
                        {0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A},
                        {0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E},
                        {0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF},
                        {0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16}};

const int Sq[16][16] = {{0x25, 0x24, 0x73, 0x67, 0xD7, 0xAE, 0x5C, 0x30, 0xA4, 0xEE, 0x6E, 0xCB, 0x7D, 0xB5, 0x82, 0xDB},
                        {0xE4, 0x8E, 0x48, 0x49, 0x4F, 0x5D, 0x6A, 0x78, 0x70, 0x88, 0xE8, 0x5F, 0x5E, 0x84, 0x65, 0xE2},
                        {0xD8, 0xE9, 0xCC, 0xED, 0x40, 0x2F, 0x11, 0x28, 0x57, 0xD2, 0xAC, 0xE3, 0x4A, 0x15, 0x1B, 0xB9},
                        {0xB2, 0x80, 0x85, 0xA6, 0x2E, 0x02, 0x47, 0x29, 0x07, 0x4B, 0x0E, 0xC1, 0x51, 0xAA, 0x89, 0xD4},
                        {0xCA, 0x01, 0x46, 0xB3, 0xEF, 0xDD, 0x44, 0x7B, 0xC2, 0x7F, 0xBE, 0xC3, 0x9F, 0x20, 0x4C, 0x64},
                        {0x83, 0xA2, 0x68, 0x42, 0x13, 0xB4, 0x41, 0xCD, 0xBA, 0xC6, 0xBB, 0x6D, 0x4D, 0x71, 0x21, 0xF4},
                        {0x8D, 0xB0, 0xE5, 0x93, 0xFE, 0x8F, 0xE6, 0xCF, 0x43, 0x45, 0x31, 0x22, 0x37, 0x36, 0x96, 0xFA},
                        {0xBC, 0x0F, 0x08, 0x52, 0x1D, 0x55, 0x1A, 0xC5, 0x4E, 0x23, 0x69, 0x7A, 0x92, 0xFF, 0x5B, 0x5A},
                        {0xEB, 0x9A, 0x1C, 0xA9, 0xD1, 0x7E, 0x0D, 0xFC, 0x50, 0x8A, 0xB6, 0x62, 0xF5, 0x0A, 0xF8, 0xDC},
                        {0x03, 0x3C, 0x0C, 0x39, 0xF1, 0xB8, 0xF3, 0x3D, 0xF2, 0xD5, 0x97, 0x66, 0x81, 0x32, 0xA0, 0x00},
                        {0x06, 0xCE, 0xF6, 0xEA, 0xB7, 0x17, 0xF7, 0x8C, 0x79, 0xD6, 0xA7, 0xBF, 0x8B, 0x3F, 0x1F, 0x53},
                        {0x63, 0x75, 0x35, 0x2C, 0x60, 0xFD, 0x27, 0xD3, 0x94, 0xA5, 0x7C, 0xA1, 0x05, 0x58, 0x2D, 0xBD},
                        {0xD9, 0xC7, 0xAF, 0x6B, 0x54, 0x0B, 0xE0, 0x38, 0x04, 0xC8, 0x9D, 0xE7, 0x14, 0xB1, 0x87, 0x9C},
                        {0xDF, 0x6F, 0xF9, 0xDA, 0x2A, 0xC4, 0x59, 0x16, 0x74, 0x91, 0xAB, 0x26, 0x61, 0x76, 0x34, 0x2B},
                        {0xAD, 0x99, 0xFB, 0x72, 0xEC, 0x33, 0x12, 0xDE, 0x98, 0x3B, 0xC0, 0x9B, 0x3E, 0x18, 0x10, 0x3A},
                        {0x56, 0xE1, 0x77, 0xC9, 0x1E, 0x9E, 0x95, 0xA3, 0x90, 0x19, 0xA8, 0x6C, 0x09, 0xD0, 0xF0, 0x86}};

unsigned long s0, s1, s2, s3, s4, s5, s6, s7, s8, s9, s10, s11, s12, s13, s14, s15;
unsigned long R1, R2, R3;

unsigned char MULx(unsigned char V, unsigned char c){
    
    if((V & 0x80) == 0x80){
    
        V = (V << 1) & 0xFF;
        return V ^ c;
    }
        return (V << 1) & 0xFF;
    
    }

unsigned char MULy(unsigned char V, unsigned int i, unsigned char c){
    
    if(i == 0)
    {
        return V;
    }
    
        return MULx(MULy(V,i-1,c), c);
    
}

unsigned int MULa(unsigned char c){
    return (MULy(c, 23, 0xA9) << 24) | (MULy(c, 245, 0xA9)<< 16) | (MULy(c, 48, 0xA9) << 8) | (MULy(c, 239, 0xA9)) ;

}

unsigned int DIVa(unsigned char c){
    return (MULy(c, 16, 0xA9) << 24) | (MULy(c, 39, 0xA9) << 16) | (MULy(c, 6, 0xA9) << 8) | (MULy(c, 64, 0xA9));

}

unsigned char SR(unsigned int x){
    unsigned char x0, x1;
    x0 = (x & 0xF0) >> 4;
    x1 = (x & 0x0F);
    return Sr[x0][x1];
}

unsigned char SQ(unsigned int x){
    unsigned char x0, x1;
       x0 = (x & 0xF0) >> 4;
       x1 = (x & 0x0F);
       return Sq[x0][x1];
}

unsigned int S1box(unsigned int w){
    unsigned int w0, w1, w2, w3;
    w0 = (w & 0xFF000000) >> 24;
    w1 = (w & 0x00FF0000) >> 16;
    w2 = (w & 0x0000FF00) >> 8;
    w3 = (w & 0x000000FF);
    
    unsigned int r0, r1, r2, r3;
    r0 = (MULx(SR(w0), 0x1B) ^ SR(w1) ^ SR(w2) ^ MULx(SR(w3), 0x1B) ^ SR(w3)) << 24;
    r1 = (MULx(SR(w0), 0x1B) ^ SR(w0) ^ MULx(SR(w1), 0x1B) ^ SR(w2) ^ SR(w3)) << 16;
    r2 = (SR(w0) ^ MULx(SR(w1), 0x1B) ^ SR(w1) ^ MULx(SR(w2), 0x1B) ^ SR(w3)) << 8;
    r3 = (SR(w0) ^ SR(w1) ^ MULx(SR(w2), 0x1B) ^ SR(w2) ^ MULx(SR(w3), 0x1B));
    return (r0 | r1 | r2 | r3);
}

unsigned int S2box(unsigned int w){

    unsigned int w0, w1, w2, w3;
       w0 = (w & 0xFF000000) >> 24;
       w1 = (w & 0x00FF0000) >> 16;
       w2 = (w & 0x0000FF00) >> 8;
       w3 = (w & 0x000000FF);
       
       unsigned int r0, r1, r2, r3;
       r0 = (MULx(SQ(w0), 0x69) ^ SQ(w1) ^ SQ(w2) ^ (MULx(SQ(w3), 0x69) ^ SQ(w3))) << 24;
       r1 = ((MULx(SQ(w0), 0x69) ^ SQ(w0)) ^ MULx(SQ(w1), 0x69) ^ SQ(w2) ^ SQ(w3)) << 16;
       r2 = (SQ(w0) ^ (MULx(SQ(w1), 0x69) ^ SQ(w1)) ^ MULx(SQ(w2), 0x69) ^ SQ(w3)) << 8;
       r3 = (SQ(w0) ^ SQ(w1) ^ (MULx(SQ(w2), 0x69) ^ SQ(w2)) ^ MULx(SQ(w3), 0x69));
       return (r0 | r1 | r2 | r3);
       
}



void clockLFSR(unsigned int F, int mode){
    int v, s00, s01, s02, s03, s110, s111, s112, s113;
    s00 = (s0 & 0xFF000000) >> 24;
    s01 = (s0 & 0x00FF0000) << 8;
    s02 = (s0 & 0x0000FF00) << 8;
    s03 = (s0 & 0x000000FF) << 8;
    s110 = (s11 & 0xFF000000) >> 8;
    s111 = (s11 & 0x00FF0000) >> 8;
    s112 = (s11 & 0x0000FF00) >> 8;
    s113 = (s11 & 0x000000FF);
    
    if(mode == 1)
    {
        v = (s01 | s02 | s03| 0x00) ^ MULa(s00) ^ s2 ^ (0x00 |s110 | s111 | s112) ^ DIVa(s113) ^ F;
    }
    else
    {
        v = (s01 | s02 | s03|0x00) ^ MULa(s00) ^ s2 ^ (0x00 | s110 | s111 | s112) ^ DIVa(s113);
    }
    
    s0 = s1;
    s1 = s2;
    s2 = s3;
    s3 = s4;
    s4 = s5;
    s5 = s6;
    s6 = s7;
    s7 = s8;
    s8 = s9;
    s9 = s10;
    s10 = s11;
    s11 = s12;
    s12 = s13;
    s13 = s14;
    s14 = s15;
    s15 = v;
}

unsigned int clockFSM(){

    unsigned long F, r;
    F = ((s15 + R1)) ^ R2;
    r = (R2 + (R3 ^ s5)) ;
    R3 = S2box(R2);
    R2 = S1box(R1);
    R1 = r;
    return F;
}



void initialization(vector<string> K, vector<string> IV){
    unsigned int hex_data;
    std::vector<unsigned int> key_data, IV_data;
    
    for(auto s: K){
            stringstream parser(s);
            parser >> hex >> hex_data;
            key_data.push_back(hex_data);
    }
    
    for(auto s: IV){
            stringstream parser(s);
            parser >> hex >> hex_data;
            IV_data.push_back(hex_data);
    }
    
        s15 = key_data[3] ^ IV_data[0];
        s14= key_data[2];
        s13 = key_data[1];
        s12 = key_data[0] ^ IV_data[1];
        s11 = key_data[3] ^ 0xFFFFFFFF;
        s10= key_data[2] ^ 0xFFFFFFFF ^ IV_data[2];
        s9 = key_data[1] ^ 0xFFFFFFFF ^ IV_data[3];
        s8 = key_data[0] ^ 0xFFFFFFFF;
        s7 = key_data[3];
        s6= key_data[2];
        s5 = key_data[1];
        s4 = key_data[0];
        s3 = key_data[3] ^ 0xFFFFFFFF;
        s2= key_data[2]^ 0xFFFFFFFF;
        s1 = key_data[1] ^ 0xFFFFFFFF;
        s0 = key_data[0] ^ 0xFFFFFFFF;
    
    
   unsigned int F;
    R1 = R2 = R3 = 0;
    for(unsigned int i = 0; i < 32; i++)
    {
        F = clockFSM();
        clockLFSR(F, 1);
    }
}

vector<string> generate_keystream(int n, vector<string> KS){
    
   unsigned int F = clockFSM();
    clockLFSR(F, 0);

   vector<unsigned int> results;
    
    for(int i = 0; i < n; i++){
        F = clockFSM();
        unsigned int zt = (F ^ s0);
        results.push_back(zt);
        clockLFSR(F, 0);
    }
    
    for(auto i : results)
    {
        stringstream ss;
        ss << hex << i;
        string s;
        ss>>s;
        
        KS.push_back(s);
    }
    
    return KS;

}

int main(int argc, char **argv){
    vector<string> keys;
       vector<string> IV;
    if (argc != 3)
    {
        std::cout << "Usage: ./run input_file output_file" << std::endl;
        return 0;
    }

    std::ifstream file_input;
    file_input.open(argv[1]);
    if (!file_input.is_open())
    {
        std::cout << "Error opening file" << std::endl;
        return 1;
    }

    std::vector<std::string> lines;
    std::string line_str;
    while (getline(file_input, line_str))
    {
        lines.push_back(line_str);
    }

    file_input.close();

    std::string key = lines.at(0).substr(lines.at(0).find_first_of("KEY") + 4);
    std::string var = lines.at(1).substr(lines.at(1).find_first_of("VAR") + 4);
    std::string n = lines.at(2).substr(lines.at(2).find_first_of("NUM") + 4);
    
    
    istringstream iss(key);
    for(string key; iss >> key; ){
        keys.push_back(key);
    }

    istringstream ss(var);
       for(string var; ss >> var; )
           IV.push_back(var);
    
    int num = stoi(n);
    
        initialization(keys, IV);
        vector<string> KS;
       KS = generate_keystream(num, KS);

        ofstream fout(argv[2]);
        for( auto i:KS)
        {
            fout << i << endl;
            cout << i << endl;
        }
    
        
        fout.close();
        
        return 0;
                           
    
}