crack.c

crack.c

#define _XOPEN_SOURCE
#include <unistd.h>
#include <cs50.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h> 

int toasci(int c);
int main(int argc, string argv[])
{
  
  if (argc != 2)
  {
      printf("Usage: ./crack hash\n");
      return 1;
  }
  
  char passwd[5];
  string cracked; 
  int i;
  
  
      for (i = 0; i < 4; i++)
      {
            if (i == 0)
            {
              int j = 0;
              do
              {
                passwd[0] = toasci(j);
                passwd[1] = '\0';
                cracked = crypt(passwd,"50");
                j++;
                if(strcmp(cracked,argv[1]) == 0) 
                    {
                    printf("%s\n", passwd);
                    return 1; 
                    }
              } while (j < 52);
            }
            else if (i == 1)
           {
              int j = 0;
              do
              {
                passwd[0] = toasci(j);
                int k = 0;
                do{
                    passwd[1] = toasci(k);
                    passwd[2] = '\0';
                    cracked = crypt(passwd,"50");
                    k++;
                    if(strcmp(cracked,argv[1]) == 0) 
                    {
                    printf("%s\n", passwd);
                    return 1; 
                    }
                }while (k < 52);
                j++;
                
              } while (j < 52);
           }
            else if (i == 2)
           {
              int j = 0;
              do
              {
                passwd[0] = toasci(j);
                int k = 0;
                do{
                    passwd[1] = toasci(k);
                    int l = 0;
                    do
                    {
                    passwd[2] = toasci(l);
                    passwd[3] = '\0';
                    cracked = crypt(passwd,"50");
                    l++;
                    if(strcmp(cracked,argv[1]) == 0) 
                        {
                        printf("%s\n", passwd);
                        return 1; 
                        }
                    } while (l < 52);
                    k++;
                }while (k < 52);
                j++;
                
              } while (j < 52);
           }
           else if (i == 3)
           {
              int j = 0;
              do
              {
                passwd[0] = toasci(j);
                int k = 0;
                do{
                    passwd[1] = toasci(k);
                    int l = 0;
                    do
                    {
                    passwd[2] = toasci(l);
                    int m = 0;
                        do
                        {
                        passwd[3] = toasci(m);
                        passwd[4] = '\0';
                        cracked = crypt(passwd,"50");
                        m++;
                        if(strcmp(cracked,argv[1]) == 0) 
                        {
                        printf("%s\n", passwd);
                        return 1; 
                        }
                        }while (m < 52);
                        l++;
                    } while (l < 52);
                    k++;
                }while (k < 52);
                j++;
                
              } while (j < 52);
           }
           
      }
      printf("%s\n", passwd);
}

int toasci(int c)
{
    int ascii;
    if (c >= 0 && c <= 25)
    {
        ascii = 65;
        int upper = 0;
        while (upper < c)
        {
            ascii++;
            upper++;
        }
    }
    else
    {
        ascii = 97;
        int lower = 26;
        while (lower < c)
            {
                ascii++;
                lower++;
            }
    }
    
    return ascii;
}