package org.jboss.security.srp;

import java.io.IOException;
import java.io.Serializable;
import java.security.KeyException;

public interface SRPVerifierStore
{
    public static class VerifierInfo implements Serializable
    {
        /**
         * The username the information applies to. Perhaps redundant
         * but it makes the object self contained.
         */
        public String username;

        /** The SRP password verifier hash */
        public byte[] verifier;
        /** The random password salt originally used to verify the password */
        public byte[] salt;
        /** The SRP algorithm primitive generator */
        public byte[] g;
        /** The algorithm safe-prime modulus */
        public byte[] N;
    }
    
    /**
     *  Get the indicated user's password verifier information.
     */
    public VerifierInfo getUserVerifier(String username)
        throws KeyException, IOException;
    /** 
     *  Set the indicated users' password verifier information. This
     *  is equivalent to changing a user's password and should
     *  generally invalidate any existing SRP sessions and caches.
     */
    public void setUserVerifier(String username, VerifierInfo info)
        throws IOException;

    /** 
     * Verify an optional auxiliary challenge sent from the client to
     * the server.  The auxChallenge object will have been decrypted
     * if it was sent encrypted from the client. An example of a
     * auxiliary challenge would be the validation of a hardware token
     * (SafeWord, SecureID, iButton) that the server validates to
     * further strengthen the SRP password exchange.
     */
     public void verifyUserChallenge(String username, Object auxChallenge)
         throws SecurityException;
}