org.springframework.security.authentication.encoding
Interface PasswordEncoder

All Known Implementing Classes:

BaseDigestPasswordEncoder, BasePasswordEncoder, LdapShaPasswordEncoder, Md4PasswordEncoder, Md5PasswordEncoder, MessageDigestPasswordEncoder, PlaintextPasswordEncoder, ShaPasswordEncoder

public interface PasswordEncoder

Interface for performing authentication operations on a password.

Version:

$Id: PasswordEncoder.java 3550 2009-04-13 13:43:23Z ltaylor $

Author:

colin sampaleanu

Method Summary

String	encodePassword(String rawPass, Object salt) Encodes the specified raw password with an implementation specific algorithm.
boolean	isPasswordValid(String encPass, String rawPass, Object salt) Validates a specified "raw" password against an encoded password.

Method Detail

encodePassword

String encodePassword(String rawPass,
                      Object salt)
                      throws DataAccessException

Encodes the specified raw password with an implementation specific algorithm.

This will generally be a one-way message digest such as MD5 or SHA, but may also be a plaintext variant which does no encoding at all, but rather returns the same password it was fed. The latter is useful to plug in when the original password must be stored as-is.

The specified salt will potentially be used by the implementation to "salt" the initial value before encoding. A salt is usually a user-specific value which is added to the password before the digest is computed. This means that computation of digests for common dictionary words will be different than those in the backend store, because the dictionary word digests will not reflect the addition of the salt. If a per-user salt is used (rather than a system-wide salt), it also means users with the same password will have different digest encoded passwords in the backend store.

If a salt value is provided, the same salt value must be use when calling the isPasswordValid(String, String, Object) method. Note that a specific implementation may choose to ignore the salt value (via null), or provide its own.

Parameters:

rawPass - the password to encode

salt - optionally used by the implementation to "salt" the raw password before encoding. A null value is legal.

Returns:

encoded password

Throws:

DataAccessException - DOCUMENT ME!

isPasswordValid

boolean isPasswordValid(String encPass,
                        String rawPass,
                        Object salt)
                        throws DataAccessException

Validates a specified "raw" password against an encoded password.

The encoded password should have previously been generated by encodePassword(String, Object). This method will encode the rawPass (using the optional salt), and then compared it with the presented encPass.

For a discussion of salts, please refer to encodePassword(String, Object).

Parameters:

encPass - a pre-encoded password

rawPass - a raw password to encode and compare against the pre-encoded password

salt - optionally used by the implementation to "salt" the raw password before encoding. A null value is legal.

Returns:

true if the password is valid , false otherwise

Throws:

DataAccessException - DOCUMENT ME!