Crack6.c

#include <stdio.h>
#include <cs50.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <crypt.h>

// easy password for testing:

// aaaaa:50XcgR31jl/4M

// from problem set docs:

// anushree:50xcIMJ0y.RXo = YES
// brian:50mjprEcqC/ts = CA
// bjbrown:50GApilQSG3E2 = UPenn (takes a while)
// lloyd:50n0AAUD.pL8g = lloyd (takes a while)
// malan:50CcfIk1QrPr6 = maybe (takes a while)
// maria:509nVI8B9VfuA = TF
// natmelo:50JIIyhDORqMU = nope
// rob:50JGnXUgaafgc = ROFL
// stelios:51u8F0dkeDSbY = NO
// zamyla:50cI2vYkF0YU2 = LOL

bool crack(char *user_input, char *guess, char *salt);

int main(int argc, string *argv[])
{
    if (argc != 2)  // prevent the user from not entering the correct number of command line arguments
    {
        printf("Invalid Hash Needed!:\n ");
        return 1;
    }

    string *user_input = argv[1]; // declare a pointer called user input (which we have also stated is argv[1])
    char salt[3];

    for (int i = 0; i < 2; i++)
    {
        salt[i] = *user_input[i];
        salt[2] = '\0';
    }

    string alphabet = "ABC";
    char guess[1];

    for (int a1 = 0; a1 < strlen(alphabet); a1++)  // check onenote for how these forloops work
    {
        guess[0] = alphabet[a1];
        guess[1] = '\0';
        // The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed
        // that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found.
        if (crack(alphabet, guess, salt))
      {
        printf("Password is: %s\n", guess);
        return 0;
      }
    }
    printf("\n");
}

// derefrencing the pointers for user input, guess[i]th index & salt at [i]th index in our crack function so we can update these pointers declared in main within this function
// without having to fuck around with making copies of this data and passing it back etc
bool crack(char *user_input, char *guess, char *salt)
{
    char *encrypted_guess = crypt(guess, salt);

    if (strcmp(encrypted_guess, user_input) == 0)
    {
        return true;
    }
    else
    {
        return false;
    }
}