/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache License, Version 2.0 (the

  * "License"); you may not use this file except in compliance

  * with the License.  You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an

  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

  * KIND, either express or implied.  See the License for the

  * specific language governing permissions and limitations

  * under the License.

  */

 package org.apache.shiro.authc;

 import org.apache.shiro.util.ByteSource;

 /**

  * Interface representing account information that may use a salt when hashing credentials.  This interface

  * exists primarily to support environments that hash user credentials (e.g. passwords).

  * <p/>

  * Salts should typically be generated from a secure pseudo-random number generator so they are effectively

  * impossible to guess.  The salt value should be safely stored along side the account information to ensure

  * it is maintained along with the account's credentials.

  * <p/>

  * This interface exists as a way for Shiro to acquire that salt so it can correctly perform

  * {@link org.apache.shiro.authc.credential.CredentialsMatcher credentials matching} during login attempts.

  * See the {@link org.apache.shiro.authc.credential.HashedCredentialsMatcher HashedCredentialsMatcher} JavaDoc for

  * more information on hashing credentials with salts.

  *

  * @see org.apache.shiro.authc.credential.HashedCredentialsMatcher

  *

  * @since 1.1

  */

 public interface SaltedAuthenticationInfo extends AuthenticationInfo {

     /**

      * Returns the salt used to salt the account's credentials or {@code null} if no salt was used.

      *

      * @return the salt used to salt the account's credentials or {@code null} if no salt was used.

      */

     ByteSource getCredentialsSalt();

 }