com.goldencode.util

Class PasswordHelper

java.lang.Object

com.goldencode.util.PasswordHelper

public final class PasswordHelper
extends java.lang.Object

Helper class to generate salt, encrypt a password with the PBKDF2WithHmacSHA1 algorithm, and to authenticate passwords by encrypting them with the same algorithm and comparing results.

Based on an example published by Jerry Orr at http://blog.jerryorr.com/2012/05/secure-password-storage-lots-of-donts.html

Constructor Summary

Constructors

Constructor and Description
PasswordHelper()

Method Summary

Modifier and Type	Method and Description
boolean	authenticate(java.lang.String clearPassword, byte[] encryptedPassword, byte[] salt) Encrypt a clear text password candidate and compare it with the given encrypted password to determine if they match.
byte[]	encryptPassword(java.lang.String password, byte[] salt) Encrypt a password using the "PBKDF2WithHmacSHA1" algorithm.
byte[]	salt() Generate a random, 8-byte salt value for use when encrypting a password.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PasswordHelper

public PasswordHelper()

Method Detail

authenticate

public boolean authenticate(java.lang.String clearPassword,
                            byte[] encryptedPassword,
                            byte[] salt)
                     throws java.security.NoSuchAlgorithmException,
                            java.security.spec.InvalidKeySpecException

Encrypt a clear text password candidate and compare it with the given encrypted password to determine if they match.

Parameters:

clearPassword - Clear text password candidate.

encryptedPassword - Previously encrypted password.

salt - Salt to use with encryption algorithm.

Returns:

True if the candidate represents the correct password, else false.

Throws:

java.security.NoSuchAlgorithmException - if the requested encryption algorithm is not available in the current environment.

java.security.spec.InvalidKeySpecException - if the specifications for the cryptographic key are invalid.

encryptPassword

public byte[] encryptPassword(java.lang.String password,
                              byte[] salt)
                       throws java.security.NoSuchAlgorithmException,
                              java.security.spec.InvalidKeySpecException

Encrypt a password using the "PBKDF2WithHmacSHA1" algorithm.

Parameters:

password - Clear text password to encrypt.

salt - Salt to use with encryption algorithm.

Returns:

Encrypted password as a byte array.

Throws:

java.security.NoSuchAlgorithmException - if the requested encryption algorithm is not available in the current environment.

java.security.spec.InvalidKeySpecException - if the specifications for the cryptographic key are invalid.

salt

public byte[] salt()
            throws java.security.NoSuchAlgorithmException

Generate a random, 8-byte salt value for use when encrypting a password.

Returns:

Salt value as a byte array.

Throws:

java.security.NoSuchAlgorithmException - if the requested encryption algorithm is not available in the current environment.