Java JCE and secure password storage

21 Sep 2023

In today’s digital era, secure password storage is of utmost importance to protect sensitive user information. Java Cryptography Extension (JCE) provides a robust set of cryptographic tools to ensure the confidentiality and integrity of passwords. In this blog post, we will explore the use of JCE in Java for secure password storage.

Why is Secure Password Storage Important?

Passwords are widely used for authentication in various systems, such as websites, mobile apps, and databases. Storing passwords securely is crucial to prevent unauthorized access and protect the privacy of users. Weak password storage practices can lead to devastating consequences, such as data breaches and compromised accounts.

Using Java JCE for Password Storage

Hashing with Salt

One common technique for secure password storage is to hash passwords using a salt. Salt is a random value that is appended to the password before hashing, making it harder for attackers to use precomputed tables, such as rainbow tables, for password cracking.

The following example demonstrates how to use JCE to hash passwords with salt in Java:

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Base64;

public class PasswordHashingExample {
    public static void main(String[] args) throws NoSuchAlgorithmException {
        String password = "myStrongPassword";
        
        // Generate random salt
        SecureRandom random = new SecureRandom();
        byte[] salt = new byte[16];
        random.nextBytes(salt);
        
        // Append salt to the password
        byte[] saltedPassword = new byte[password.getBytes().length + salt.length];
        System.arraycopy(password.getBytes(), 0, saltedPassword, 0, password.getBytes().length);
        System.arraycopy(salt, 0, saltedPassword, password.getBytes().length, salt.length);
        
        // Hash the salted password
        MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
        byte[] hashedPassword = messageDigest.digest(saltedPassword);
        
        // Convert to Base64 representation
        String storedPassword = Base64.getEncoder().encodeToString(hashedPassword);
        
        System.out.println("Stored Password: " + storedPassword);
    }
}

Password Verification

When verifying passwords, we need to compare the stored password with the newly provided password. Both passwords need to be hashed in the same way, using the same salt and hashing algorithm.

Here’s an example of how to verify a password using Java JCE:

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Base64;

public class PasswordVerificationExample {
    public static void main(String[] args) throws NoSuchAlgorithmException {
        String storedPassword = "bzMufkMCg3iFSzjCOaTpC3/q0MvIs2qcC+3raOrObDo=";
        String newPassword = "myStrongPassword";
        
        // Decode the stored password from Base64
        byte[] decodedPassword = Base64.getDecoder().decode(storedPassword);
        
        // Hash the new password using the same salt
        byte[] saltedPassword = new byte[newPassword.getBytes().length + salt.length];
        System.arraycopy(newPassword.getBytes(), 0, saltedPassword, 0, newPassword.getBytes().length);
        System.arraycopy(salt, 0, saltedPassword, newPassword.getBytes().length, salt.length);
        
        MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
        byte[] hashedPassword = messageDigest.digest(saltedPassword);
        
        // Compare the stored password with the newly hashed password
        if (MessageDigest.isEqual(decodedPassword, hashedPassword)) {
            System.out.println("Password is correct!");
        } else {
            System.out.println("Password is incorrect!");
        }
    }
}

Conclusion

Using the Java Cryptography Extension (JCE) for secure password storage is essential to protect user information. Hashing passwords with salt adds an extra layer of security, making it harder for attackers to obtain the original password. By following best practices for password storage, we can enhance the security of our systems and safeguard sensitive user data.

#TechBlog #Java #JCE #PasswordSecurity