weblogic.security.spi

Interface PasswordDigest

public interface PasswordDigest

The getPasswordDigest interface allows an authentication provider to return a digest for a specified user's password.

Method Summary

Modifier and Type	Method and Description
byte[]	getPasswordDigest(String username, byte[] seed, int numBytes) Returns the digest value for the password for the specified username.

Method Detail

getPasswordDigest

byte[] getPasswordDigest(String username,
                         byte[] seed,
                         int numBytes)
                  throws DigestNotAvailableException

Returns the digest value for the password for the specified username. The seed and password are used to calculate a digest. This digest can then be used as a shared secret in cryptographic operations. A provider must implement the HMAC_SHA-1 algorithm for calculating the digest value. The HMAC_SHA-1 algorithm is described in section 5 of RFC 2246. The algorithm is as follows:

   P_SHA-1(secret, seed) = HMAC_SHA-1(secret, A(1) + seed) +
                           HMAC_SHA-1(secret, A(2) + seed) + 
                           HMAC_SHA-1(secret, A(3) + seed) + ...
 

Where:

     + indicates concatenation and
     A() is defined as: A(0) = seed and A(i) = HMAC_SHA-1 (secret, A(I-1)).
 

This digest functionality is currently used by the web services container.

Parameters:

username - String containing the user

seed - byte array of random value

numBytes - int number of bytes to return in password digest

Returns:

the digest value specific to the password and seed

Throws:

DigestNotAvailableException