1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.shiro.web.filter.authc;
20
21 import org.apache.shiro.web.filter.PathMatchingFilter;
22
23 import javax.servlet.ServletRequest;
24 import javax.servlet.ServletResponse;
25
26 /**
27 * Filter that allows access to a path immeidately without performing security checks of any kind.
28 * <p/>
29 * This filter is useful primarily in exclusionary policies, where you have defined a url pattern
30 * to require a certain security level, but maybe only subset of urls in that pattern should allow any access.
31 * <p/>
32 * For example, if you had a user-only section of a website, you might want to require that access to
33 * any url in that section must be from an authenticated user.
34 * <p/>
35 * Here is how that would look in the IniShiroFilter configuration:
36 * <p/>
37 * <code>[urls]<br/>
38 * /user/** = authc</code>
39 * <p/>
40 * But if you wanted <code>/user/signup/**</code> to be available to anyone, you have to exclude that path since
41 * it is a subset of the first. This is where the AnonymousFilter ('anon') is useful:
42 * <p/>
43 * <code>[urls]<br/>
44 * /user/signup/** = anon<br/>
45 * /user/** = authc</code>>
46 * <p/>
47 * Since the url pattern definitions follow a 'first match wins' paradigm, the <code>anon</code> filter will
48 * match the <code>/user/signup/**</code> paths and the <code>/user/**</code> path chain will not be evaluated.
49 *
50 * @since 0.9
51 */
52 public class AnonymousFilter extends PathMatchingFilter {
53
54 /**
55 * Always returns <code>true</code> allowing unchecked access to the underlying path or resource.
56 *
57 * @return <code>true</code> always, allowing unchecked access to the underlying path or resource.
58 */
59 @Override
60 protected boolean onPreHandle(ServletRequest request, ServletResponse response, Object mappedValue) {
61 // Always return true since we allow access to anyone
62 return true;
63 }
64
65 }