Key Expansion included AES encrypt

aesEncrypt.cpp

#include <iostream>
#include "AESConstants.h"
#include <fstream>
#include <string>
using namespace std;

// Input the plaintext and the key
void inputData(char* plainText, char* key)
{
    // Variable to contain user's file name
    string fileName, keyFileName;
    
    // Variable to contain file length
    int fileLength;
    
    // Variable to access file content
    ifstream plainTextFile;
    ifstream keyFile;
    
    // User is prompted to input file name
    cout << "Enter the plaintext file: ";
    getline(cin, fileName);
    cout << "Enter the key file: ";
    getline(cin, keyFileName);
    
    // File given by user is open
    plainTextFile.open(fileName);
    keyFile.open(keyFileName);
    
    // Checks if failure occurred during opening of file
    if (plainTextFile.fail() || keyFile.fail())
    {
        cout << "Failed to open file." << endl;
        return ;
    }
    
    // Length of file is obtained
    plainTextFile.seekg(0, plainTextFile.end);
    fileLength = plainTextFile.tellg();
    plainTextFile.seekg(0, plainTextFile.beg);
    
    keyFile.seekg(0, keyFile.end);
    fileLength = keyFile.tellg();
    keyFile.seekg(0, keyFile.beg);
    
    // Content of file is being stored in a character
    // array
    int counter = 0;
    while (!plainTextFile.eof())
    {
        plainTextFile.get(plainText[counter]);
        counter++;
    }
    
    counter = 0;
    while (!keyFile.eof())
    {
        keyFile.get(key[counter]);
        counter++;
    }
    
    // Closes file being read
    plainTextFile.close();
    keyFile.close();
}

// Implementing the key expansion algorithm
void keyExpansionCore(char * input, int rConIteration)
{
    //Rotate
    char t = input[0];
    input[0] = input[1];
    input[1] = input[2];
    input[2] = input[3];
    input[3] = t;
    
    //SBox replace
    input[0] = SBOX[input[0]];
    input[1] = SBOX[input[1]];
    input[2] = SBOX[input[2]];
    input[3] = SBOX[input[3]];
    
    //XOR first byte with RCON
    input[0] = input[0]^RCON[rConIteration];
}

void keyExpansion(char* key, char* expandedKey)
{
    for (int i=0;i<16;i++)
        expandedKey[i] = key[i];
    
    int bytesGenerated = 16;
    char tmp[4];
    int rconIteration = 1;
    
    while(bytesGenerated < 176)
    {
        for (int i=0;i<4;i++)
            tmp[i] = expandedKey[i+bytesGenerated-4];
        
        if (bytesGenerated%16 == 0)
            keyExpansionCore(tmp, rconIteration++);
        
        for (int j=0;j<4;j++)
        {
            expandedKey[bytesGenerated] = expandedKey[bytesGenerated-16] ^ tmp[j];
            bytesGenerated++;
        }
    }
}

// TODO: XOR the given state with a round key
//       from the key expansion algorithm.
char* addRoundKey() { return NULL; }

// TODO: Substitute bytes of the given state using S-Box
void substituteBytes(char* state)
{
    for (int i=0; i<16;i++)
    {
        state[i] = SBOX[state[i]];
    }
}

// TODO: Implementing shift left on the given state
void shiftRows() {}

// TODO: Matrix multiplication with the provided matrix.
void multiplyColumns() {}

// Encrypts 16 bytes of data at a time
char* encryptData(char* Plaintext, char* expandedKey)
{
    char state[16];
    
    // Making a copy of the message as the initial state.
    for(int j=0;j<16;j++)
    {
        state[j] = Plaintext[j];
    }
    
    char* ciphertext;
    addRoundKey();
    int nr_Rounds = 10; // for 128bit encryption
    
    for(int i=0;i<nr_Rounds;i++)
    {
        substituteBytes(state);
        shiftRows();
        multiplyColumns();
        addRoundKey();
    }
    
    //Final Round
    substituteBytes(state);
    shiftRows();
    ciphertext = addRoundKey();
    
    return ciphertext;
}

int main()
{
    char key[16];
    char plainText[100];
    
    inputData(plainText, key);
    
    char expandedKey[176];
    keyExpansion(key, expandedKey);
    
    // In the last phase of the project, we need to loop for
    // every 16 bytes of the message since the message can
    // be more than 16 bytes long.
//    char* cipherText = encryptData(plainText, key);
    //cout << &cipherText;
    
    // I include this since I'm running it on Microsoft Visual Studios
    // to be able to see the output in the console
    // feel free to remove it when you test it on your computer
    system("pause");
    
    cout << plainText <<endl;
    cout<< key <<endl;
    
    return 0;
}