filter/plugins/SourceChecker__Plugin.java

/* 
 * i-scream central monitoring system
 * http://www.i-scream.org.uk
 * Copyright (C) 2000-2002 i-scream
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

//---PACKAGE DECLARATION---
package uk.org.iscream.cms.server.filter.plugins;

//---IMPORTS---
import uk.org.iscream.cms.server.filter.PluginFilter;
import uk.org.iscream.cms.server.filter.*;
import uk.org.iscream.cms.server.core.*;
import uk.org.iscream.cms.util.*;
import uk.org.iscream.cms.server.componentmanager.*;

/**
 * This plugin is designed to check the source of incoming
 * packets, and ensure the source machine is permitted to
 * send packets through the system.
 *
 * @author  $Author: tdb $
 * @version $Id: SourceChecker__Plugin.java,v 1.4 2002/05/21 16:47:18 tdb Exp $
 */
public class SourceChecker__Plugin implements PluginFilter {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.4 $";
    
    public final String DESC = "Checks the machine_name attribute in the packet attributes. This must machine must be permitted by the ACL to allow the packet through.";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    public SourceChecker__Plugin() {
        // setup an empty ACL defaulting to ALLOW
        _acl = new ACL(ACL.ALLOW);
    }

//---PUBLIC METHODS---

    // apply the filter and return true if successful.
    public boolean runFilter(XMLPacket packet){
        String newStringACL;
        // get hold of the ACL in the configuration
        try {
            newStringACL = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.SourceCheckerPluginACL");
        }
        catch(PropertyNotFoundException e) {
            // if we can't find it, we'll just use a null ACL
            newStringACL = "";
            _logger.write(toString(), Logger.WARNING, "No ACL found for SourceChecker__Plugin, using empty ACL instead : " + e);
        }
        // check to see if the ACL has changed
        if(!newStringACL.equals(_stringACL)) {
            _logger.write(toString(), Logger.SYSMSG, "Reloading Access Control List");
            // clear the ACL
            _acl.clear();
            // set the default to something sane
            _acl.setDefaultMode(ACL.ALLOW);
            // add the new ACL (this may change the default)
            _acl.add(newStringACL);
            _stringACL = newStringACL;
        }
        
        // only want to check data or heartbeat packets
        // any others will probably get filtered out further up the filter chain
        if(packet.getParam("packet.attributes.type").equals("data") ||
           packet.getParam("packet.attributes.type").equals("heartbeat")) {
            // check the machine name against the ACL
            // we could check the IP too... but it's a lot of work for _every_ packet... maybe...
            return _acl.check(packet.getParam("packet.attributes.machine_name"));
        }
        
        // a good catchall, I guess
        // it's not a data or heartbeat packet, in which case it should go through
        return true;
    }

    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * This uses the uk.org.iscream.cms.util.NameFormat class
     * to format the toString()
     *
     * @return the name of this class and its CVS revision
     */
    public String toString() {
        return FormatName.getName(
            _name,
            getClass().getName(),
            REVISION);
    }

    /**
     * return the String representation of what the filter does
     */
    public String getDescription(){
        return DESC;
    }

//---PRIVATE METHODS---

//---ACCESSOR/MUTATOR METHODS---

//---ATTRIBUTES---

    /**
     * This is the friendly identifier of the
     * component this class is running in.
     * eg, a Filter may be called "filter1",
     * If this class does not have an owning
     * component,  a name from the configuration
     * can be placed here.  This name could also
     * be changed to null for utility classes.
     */
    private String _name = FilterMain.NAME;

    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    private Logger _logger = ReferenceManager.getInstance().getLogger();

    /**
     * This holds the ACL for the plugin.
     */
    private ACL _acl;
    
    /**
     * The current String representation of our ACL.
     */
    private String _stringACL = "";

//---STATIC ATTRIBUTES---

}
Revision:	1.5
Committed:	Wed Feb 5 16:43:47 2003 UTC (21 years, 4 months ago) by tdb
Branch:	MAIN
Changes since 1.4:	+4 -4 lines
Log Message:	Changed the server to use the external util package. Quite a minor change, but does affect a lot of files.
#	User	Rev	Content
1	tdb	1.3	/*
2			* i-scream central monitoring system
3	tdb	1.4	* http://www.i-scream.org.uk
4	tdb	1.3	* Copyright (C) 2000-2002 i-scream
5			*
6			* This program is free software; you can redistribute it and/or
7			* modify it under the terms of the GNU General Public License
8			* as published by the Free Software Foundation; either version 2
9			* of the License, or (at your option) any later version.
10			*
11			* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with this program; if not, write to the Free Software
18			* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19			*/
20
21	tdb	1.1	//---PACKAGE DECLARATION---
22			package uk.org.iscream.cms.server.filter.plugins;
23
24			//---IMPORTS---
25			import uk.org.iscream.cms.server.filter.PluginFilter;
26			import uk.org.iscream.cms.server.filter.*;
27			import uk.org.iscream.cms.server.core.*;
28	tdb	1.5	import uk.org.iscream.cms.util.*;
29	tdb	1.1	import uk.org.iscream.cms.server.componentmanager.*;
30
31			/**
32			* This plugin is designed to check the source of incoming
33			* packets, and ensure the source machine is permitted to
34			* send packets through the system.
35			*
36	tdb	1.2	* @author $Author: tdb $
37	tdb	1.5	* @version $Id: SourceChecker__Plugin.java,v 1.4 2002/05/21 16:47:18 tdb Exp $
38	tdb	1.1	*/
39			public class SourceChecker__Plugin implements PluginFilter {
40
41			//---FINAL ATTRIBUTES---
42
43			/**
44			* The current CVS revision of this class
45			*/
46	tdb	1.5	public final String REVISION = "$Revision: 1.4 $";
47	tdb	1.1
48			public final String DESC = "Checks the machine_name attribute in the packet attributes. This must machine must be permitted by the ACL to allow the packet through.";
49
50			//---STATIC METHODS---
51
52			//---CONSTRUCTORS---
53
54			public SourceChecker__Plugin() {
55	tdb	1.2	// setup an empty ACL defaulting to ALLOW
56			_acl = new ACL(ACL.ALLOW);
57	tdb	1.1	}
58
59			//---PUBLIC METHODS---
60
61			// apply the filter and return true if successful.
62			public boolean runFilter(XMLPacket packet){
63	tdb	1.2	String newStringACL;
64			// get hold of the ACL in the configuration
65			try {
66			newStringACL = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.SourceCheckerPluginACL");
67			}
68			catch(PropertyNotFoundException e) {
69			// if we can't find it, we'll just use a null ACL
70			newStringACL = "";
71			_logger.write(toString(), Logger.WARNING, "No ACL found for SourceChecker__Plugin, using empty ACL instead : " + e);
72			}
73			// check to see if the ACL has changed
74			if(!newStringACL.equals(_stringACL)) {
75			_logger.write(toString(), Logger.SYSMSG, "Reloading Access Control List");
76			// clear the ACL
77			_acl.clear();
78			// set the default to something sane
79			_acl.setDefaultMode(ACL.ALLOW);
80			// add the new ACL (this may change the default)
81			_acl.add(newStringACL);
82			_stringACL = newStringACL;
83			}
84	tdb	1.1
85			// only want to check data or heartbeat packets
86			// any others will probably get filtered out further up the filter chain
87	tdb	1.2	if(packet.getParam("packet.attributes.type").equals("data") \|\|
88			packet.getParam("packet.attributes.type").equals("heartbeat")) {
89	tdb	1.1	// check the machine name against the ACL
90			// we could check the IP too... but it's a lot of work for _every_ packet... maybe...
91			return _acl.check(packet.getParam("packet.attributes.machine_name"));
92			}
93
94			// a good catchall, I guess
95	tdb	1.2	// it's not a data or heartbeat packet, in which case it should go through
96	tdb	1.1	return true;
97			}
98
99			/**
100			* Overrides the {@link java.lang.Object#toString() Object.toString()}
101			* method to provide clean logging (every class should have this).
102			*
103	tdb	1.5	* This uses the uk.org.iscream.cms.util.NameFormat class
104	tdb	1.1	* to format the toString()
105			*
106			* @return the name of this class and its CVS revision
107			*/
108			public String toString() {
109			return FormatName.getName(
110			_name,
111			getClass().getName(),
112			REVISION);
113			}
114
115			/**
116			* return the String representation of what the filter does
117			*/
118			public String getDescription(){
119			return DESC;
120			}
121
122			//---PRIVATE METHODS---
123
124			//---ACCESSOR/MUTATOR METHODS---
125
126			//---ATTRIBUTES---
127
128			/**
129			* This is the friendly identifier of the
130			* component this class is running in.
131			* eg, a Filter may be called "filter1",
132			* If this class does not have an owning
133			* component, a name from the configuration
134			* can be placed here. This name could also
135			* be changed to null for utility classes.
136			*/
137			private String _name = FilterMain.NAME;
138
139			/**
140			* This holds a reference to the
141			* system logger that is being used.
142			*/
143			private Logger _logger = ReferenceManager.getInstance().getLogger();
144
145			/**
146			* This holds the ACL for the plugin.
147			*/
148			private ACL _acl;
149	tdb	1.2
150			/**
151			* The current String representation of our ACL.
152			*/
153			private String _stringACL = "";
154	tdb	1.1
155			//---STATIC ATTRIBUTES---
156
157			}