Java-Lab-009 - Password Cracking a REAL Linux Shadow File

PART 1 - Create User Class

• Create a Class called User that has 2 String instance variables:

private String username;
private String passHash;

• Create a User constructor that has 2 parameters username and passHash and assigns these parameters to its instance variables.
• Create 2 methods getUsername and getPassHash that return the instance variables respectively.

PART 2 - Implement method parseShadow

• Analyze the method signature parseShadow and note what it's return type is below:
  • Return Type?
• A Unix/Linux Shadow file contains username and password hashes for each user seperated by a delimiter :
• In this section, follow the steps below to parse each username and password hash out of the provided Shadow file and store it in a user array.
• Complete the body of the parseShadow method utilizing:
  • the pre-complete method getLineCount to create a user array called Users
  • imported class FileInputStream
  • imported class Scanner
  • a while loop that uses the above 2 imported classes to read the resources/shadow file line by line.
  • the split method and the delimiter : to split each line into a string array (i.e. String[])
  • use the first 2 elements of the split string array to create a new User(element1, element2)
  • and finally store each new User into a User array (i.e. User[] users), and return the array.

PART 3 - Implement method crack

• Finish implementing the method crack to do the following:
  • Similar to your parseShadow method, use the FileInputStream and Scanner class to read the resources/englishSmall.dic file line by line.
    • Note: the file path should be passed in a parameter.
  • For each word read from your englishSmall.dic dictionary iterate over your User[] array and use the Crypt library to build a password hash of the dictionary word.

    String hash = Crypt.crypt(word, user.getPassHash());

  • Add a conditional to compare the generated hash with each user's password hash.
    • Note: only compare users with $ in their password hashes, otherwise you'll get an error.
  • If the user's password hash matches the generated hash, print out:

    Found password X for user Y.
    

PART 4 - Turn In

• Make sure to use the Git tab at the bottom of IntelliJ to create a Feature1 feature branch
• Commit and Push your running code back to your GitHub account
• Issue a Pull request back to my Java-Lab-009 repo
• Cut and Paste the Pull request URL into your Canvas assignment to turn it in.