KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > turbine > modules > actions > sessionvalidator > TemplateSecureSessionValidator


1 package org.apache.turbine.modules.actions.sessionvalidator;
2
3 /*
4  * Copyright 2001-2004 The Apache Software Foundation.
5  *
6  * Licensed under the Apache License, Version 2.0 (the "License")
7  * you may not use this file except in compliance with the License.
8  * 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, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  */
18
19 import org.apache.commons.configuration.Configuration;
20
21 import org.apache.commons.lang.StringUtils;
22
23 import org.apache.commons.logging.Log;
24 import org.apache.commons.logging.LogFactory;
25
26 import org.apache.turbine.Turbine;
27 import org.apache.turbine.TurbineConstants;
28
29 import org.apache.turbine.services.security.TurbineSecurity;
30
31 import org.apache.turbine.util.RunData;
32 import org.apache.turbine.util.TurbineException;
33
34 /**
35  * SessionValidator that requires login for use with Template Services
36  * like Velocity or WebMacro.
37  *
38  * <br>
39  *
40  * Templating services requires a different Session Validator
41  * because of the way it handles screens. If you use the WebMacro or
42  * Velocity Service with the DefaultSessionValidator, users will be able to
43  * bypass login by directly addressing the template using
44  * template/index.wm. This is because the Page class looks for the
45  * keyword "template" in the Path information and if it finds it will
46  * reset the screen using it's lookup mechanism and thereby bypass
47  * Login.
48  *
49  * Note that you will need to set the template.login property to the
50  * login template.
51  *
52  * @author <a HREF="mailto:john.mcnally@clearink.com">John D. McNally</a>
53  * @author <a HREF="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
54  * @author <a HREF="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
55  * @version $Id: TemplateSecureSessionValidator.java,v 1.11.2.3 2004/05/20 03:03:53 seade Exp $
56  */
57 public class TemplateSecureSessionValidator
58     extends SessionValidator
59 {
60     /** Logging */
61     private static Log log = LogFactory.getLog(
62             TemplateSecureSessionValidator.class);
63
64     /**
65      * doPerform is virtually identical to DefaultSessionValidator
66      * except that it calls template methods instead of bare screen
67      * methods. For example, it uses <code>setScreenTemplate</code> to
68      * load the tr.props TEMPLATE_LOGIN instead of the default's
69      * setScreen to TurbineConstants.SCREEN_LOGIN.
70      *
71      * @see DefaultSessionValidator
72      * @param data Turbine information.
73      * @throws TurbineException The anonymous user could not be obtained
74      * from the security service
75      */
76     public void doPerform(RunData data)
77             throws TurbineException
78     {
79         Configuration conf = Turbine.getConfiguration();
80
81         // Pull user from session.
82 data.populate();
83
84         // The user may have not logged in, so create a "guest/anonymous" user.
85 if (data.getUser() == null)
86         {
87             log.debug("Fixing up empty User Object!");
88             data.setUser(TurbineSecurity.getAnonymousUser());
89             data.save();
90         }
91
92         // This is the secure sessionvalidator, so user must be logged in.
93 if (!data.getUser().hasLoggedIn())
94         {
95             log.debug("User is not logged in!");
96
97             // only set the message if nothing else has already set it
98 // (e.g. the LogoutUser action).
99 if (StringUtils.isEmpty(data.getMessage()))
100             {
101                 data.setMessage(conf.getString(TurbineConstants.LOGIN_MESSAGE));
102             }
103
104             // Set the screen template to the login page.
105 String JavaDoc loginTemplate =
106                 conf.getString(TurbineConstants.TEMPLATE_LOGIN);
107
108             log.debug("Sending User to the Login Screen ("
109                     + loginTemplate + ")");
110             data.getTemplateInfo().setScreenTemplate(loginTemplate);
111
112             // We're not doing any actions buddy! (except action.login which
113 // will have been performed already)
114 data.setAction(null);
115         }
116
117         log.debug("Login Check finished!");
118
119         // Make sure we have some way to return a response.
120 if (!data.hasScreen() && StringUtils.isEmpty(
121                 data.getTemplateInfo().getScreenTemplate()))
122         {
123             String JavaDoc template = conf.getString(
124                     TurbineConstants.TEMPLATE_HOMEPAGE);
125
126             if (StringUtils.isNotEmpty(template))
127             {
128                 data.getTemplateInfo().setScreenTemplate(template);
129             }
130             else
131             {
132                 data.setScreen(conf.getString(
133                         TurbineConstants.SCREEN_HOMEPAGE));
134             }
135         }
136
137         // The session_access_counter can be placed as a hidden field in
138 // forms. This can be used to prevent a user from using the
139 // browsers back button and submitting stale data.
140 // FIXME!! a template needs to be written to use this with templates.
141
142         if (data.getParameters().containsKey("_session_access_counter")
143                 && !TurbineSecurity.isAnonymousUser(data.getUser()))
144         {
145             // See comments in screens.error.InvalidState.
146 if (data.getParameters().getInt("_session_access_counter")
147                     < (((Integer JavaDoc) data.getUser().getTemp(
148                     "_session_access_counter")).intValue() - 1))
149             {
150                 if (data.getTemplateInfo().getScreenTemplate() != null)
151                 {
152                     data.getUser().setTemp("prev_template",
153                             data.getTemplateInfo().getScreenTemplate()
154                             .replace('/', ','));
155                     data.getTemplateInfo().setScreenTemplate(conf.getString(
156                             TurbineConstants.TEMPLATE_INVALID_STATE));
157                 }
158                 else
159                 {
160                     data.getUser().setTemp("prev_screen",
161                                            data.getScreen().replace('/', ','));
162                     data.setScreen(conf.getString(
163                             TurbineConstants.SCREEN_INVALID_STATE));
164                 }
165                 data.getUser().setTemp("prev_parameters", data.getParameters());
166                 data.setAction("");
167             }
168         }
169
170         // We do not want to allow both a screen and template parameter.
171 // The template parameter is dominant.
172 if (data.getTemplateInfo().getScreenTemplate() != null)
173         {
174             data.setScreen(null);
175         }
176     }
177 }
178
Popular Tags