server/filter/KeyManager.java

/* 
 * i-scream central monitoring system
 * 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;

//---IMPORTS---
import uk.org.iscream.cms.server.util.*;
import uk.org.iscream.cms.server.core.*;
import uk.org.iscream.cms.server.componentmanager.*;
import java.util.Random;
import java.util.HashMap;

/**
 * Acts as a store and checking mechanism for host keys.
 *
 * @author  $Author: tdb $
 * @version $Id: KeyManager.java,v 1.2 2002/03/22 14:22:58 tdb Exp $
 */
public class KeyManager {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.2 $";
    
    /**
     * The set of characters to be used for our keys
     */
    private final char[] KEYSET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray();
    
    /**
     * Default key length
     */
    public static final int DEFKEYLEN = 15;
    
//---STATIC METHODS---

    /**
     * Return a reference to the single class.
     * Construct it if it does not already exist, otherwise just return the reference.
     */
    public synchronized static KeyManager getInstance() {
        if (_instance == null){
            _instance = new KeyManager();
        }
        return _instance;
    }

//---CONSTRUCTORS---
    
    /**
     * Private constructor to avoid external construction.
     */
    private KeyManager() {
        try {
            String keylen = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.KeyLength");
            _keylen = Integer.parseInt(keylen);
        }
        catch (PropertyNotFoundException e) {
            _keylen = DEFKEYLEN;
            _logger.write(toString(), Logger.WARNING, "No key length found, using default of " +_keylen+ " : " + e);
        }
        catch (NumberFormatException e) {
            _keylen = DEFKEYLEN;
            _logger.write(toString(), Logger.WARNING, "Malformed key length found, using default of " +_keylen+ " : " + e);
        }
    }

//---PUBLIC METHODS---
    
    /**
     * Add or replace a key.
     *
     * @param host the hostname to add a key for
     * @param key the key to add
     */
    public synchronized void addKey(String host, String key) {
        _keys.put(host, key);
    }
    
    /**
     * Check if a given key is currently valid.
     * Will respond negatively if the key doesn't match,
     * or if no key is found (and EnforceHostAuth is on).
     *
     * @param host the hostname to check the key for
     * @param key the key to check
     * @return whether the check was successful
     */
    public synchronized boolean checkKey(String host, String key) {
        Object o = _keys.get(host);
        if(o != null) {
            // if our key isn't null, we want to make
            // sure it matches that given
            String ourKey = (String) o;
            return ourKey.equals(key);
        }
        else {
            // default to enforcing host auth
            boolean enforceHostAuth = true;
            try {
                // try to get see what's in the config
                String enforce = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.EnforceHostAuth");
                enforceHostAuth = (Integer.parseInt(enforce) == 1);
            }
            catch(PropertyNotFoundException e) {
                // if it's not set, not enforced
                _logger.write(toString(), Logger.WARNING, "EnforceHostAuth property not found: " + e);
                enforceHostAuth = false;
            }
            catch(NumberFormatException e) {
                // if it's not a number, not enforced
                _logger.write(toString(), Logger.WARNING, "EnforceHostAuth property malformed: " + e);
                enforceHostAuth = false;
            }
            // if enforceHostAuth is true we want to fail the check
            // and vice-versa
            return !enforceHostAuth;
        }
    }
    
    /**
     * Generate a random key with length KEYLEN.
     *
     * @return a random key as a String
     */
    public String genKey() {
        Random r = new Random();
        StringBuffer s = new StringBuffer();
        for(int i=0; i < _keylen; i++) {
            s.append(KEYSET[r.nextInt(KEYSET.length)]);
        }
        return s.toString();
    }
    
    /**
     * 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.server.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);
    }

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

//---ATTRIBUTES---
    
    /**
     * This holds the current keys for
     * the hosts we're authenticating
     */
    private HashMap _keys = new HashMap();

    /**
     * The length of our keys
     */
    private int _keylen;
    
    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    private Logger _logger = ReferenceManager.getInstance().getLogger();
    
    /**
     * 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;

//---STATIC ATTRIBUTES---

    /**
     * A reference to the single instance of this class
     */
    private static KeyManager _instance;

}
Revision:	1.3
Committed:	Sat May 18 18:16:02 2002 UTC (22 years ago) by tdb
Branch:	MAIN
Changes since 1.2:	+21 -2 lines
Log Message:	i-scream is now licensed under the GPL. I've added the GPL headers to every source file, and put a full copy of the license in the appropriate places. I think I've covered everything. This is going to be a mad commit ;)
#	Content
1	/*
2	* i-scream central monitoring system
3	* Copyright (C) 2000-2002 i-scream
4	*
5	* This program is free software; you can redistribute it and/or
6	* modify it under the terms of the GNU General Public License
7	* as published by the Free Software Foundation; either version 2
8	* of the License, or (at your option) any later version.
9	*
10	* This program is distributed in the hope that it will be useful,
11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13	* GNU General Public License for more details.
14	*
15	* You should have received a copy of the GNU General Public License
16	* along with this program; if not, write to the Free Software
17	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18	*/
19
20	//---PACKAGE DECLARATION---
21	package uk.org.iscream.cms.server.filter;
22
23	//---IMPORTS---
24	import uk.org.iscream.cms.server.util.*;
25	import uk.org.iscream.cms.server.core.*;
26	import uk.org.iscream.cms.server.componentmanager.*;
27	import java.util.Random;
28	import java.util.HashMap;
29
30	/**
31	* Acts as a store and checking mechanism for host keys.
32	*
33	* @author $Author: tdb $
34	* @version $Id: KeyManager.java,v 1.2 2002/03/22 14:22:58 tdb Exp $
35	*/
36	public class KeyManager {
37
38	//---FINAL ATTRIBUTES---
39
40	/**
41	* The current CVS revision of this class
42	*/
43	public final String REVISION = "$Revision: 1.2 $";
44
45	/**
46	* The set of characters to be used for our keys
47	*/
48	private final char[] KEYSET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray();
49
50	/**
51	* Default key length
52	*/
53	public static final int DEFKEYLEN = 15;
54
55	//---STATIC METHODS---
56
57	/**
58	* Return a reference to the single class.
59	* Construct it if it does not already exist, otherwise just return the reference.
60	*/
61	public synchronized static KeyManager getInstance() {
62	if (_instance == null){
63	_instance = new KeyManager();
64	}
65	return _instance;
66	}
67
68	//---CONSTRUCTORS---
69
70	/**
71	* Private constructor to avoid external construction.
72	*/
73	private KeyManager() {
74	try {
75	String keylen = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.KeyLength");
76	_keylen = Integer.parseInt(keylen);
77	}
78	catch (PropertyNotFoundException e) {
79	_keylen = DEFKEYLEN;
80	_logger.write(toString(), Logger.WARNING, "No key length found, using default of " +_keylen+ " : " + e);
81	}
82	catch (NumberFormatException e) {
83	_keylen = DEFKEYLEN;
84	_logger.write(toString(), Logger.WARNING, "Malformed key length found, using default of " +_keylen+ " : " + e);
85	}
86	}
87
88	//---PUBLIC METHODS---
89
90	/**
91	* Add or replace a key.
92	*
93	* @param host the hostname to add a key for
94	* @param key the key to add
95	*/
96	public synchronized void addKey(String host, String key) {
97	_keys.put(host, key);
98	}
99
100	/**
101	* Check if a given key is currently valid.
102	* Will respond negatively if the key doesn't match,
103	* or if no key is found (and EnforceHostAuth is on).
104	*
105	* @param host the hostname to check the key for
106	* @param key the key to check
107	* @return whether the check was successful
108	*/
109	public synchronized boolean checkKey(String host, String key) {
110	Object o = _keys.get(host);
111	if(o != null) {
112	// if our key isn't null, we want to make
113	// sure it matches that given
114	String ourKey = (String) o;
115	return ourKey.equals(key);
116	}
117	else {
118	// default to enforcing host auth
119	boolean enforceHostAuth = true;
120	try {
121	// try to get see what's in the config
122	String enforce = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.EnforceHostAuth");
123	enforceHostAuth = (Integer.parseInt(enforce) == 1);
124	}
125	catch(PropertyNotFoundException e) {
126	// if it's not set, not enforced
127	_logger.write(toString(), Logger.WARNING, "EnforceHostAuth property not found: " + e);
128	enforceHostAuth = false;
129	}
130	catch(NumberFormatException e) {
131	// if it's not a number, not enforced
132	_logger.write(toString(), Logger.WARNING, "EnforceHostAuth property malformed: " + e);
133	enforceHostAuth = false;
134	}
135	// if enforceHostAuth is true we want to fail the check
136	// and vice-versa
137	return !enforceHostAuth;
138	}
139	}
140
141	/**
142	* Generate a random key with length KEYLEN.
143	*
144	* @return a random key as a String
145	*/
146	public String genKey() {
147	Random r = new Random();
148	StringBuffer s = new StringBuffer();
149	for(int i=0; i < _keylen; i++) {
150	s.append(KEYSET[r.nextInt(KEYSET.length)]);
151	}
152	return s.toString();
153	}
154
155	/**
156	* Overrides the {@link java.lang.Object#toString() Object.toString()}
157	* method to provide clean logging (every class should have this).
158	*
159	* This uses the uk.org.iscream.cms.server.util.NameFormat class
160	* to format the toString()
161	*
162	* @return the name of this class and its CVS revision
163	*/
164	public String toString() {
165	return FormatName.getName(
166	_name,
167	getClass().getName(),
168	REVISION);
169	}
170
171	//---PRIVATE METHODS---
172
173	//---ACCESSOR/MUTATOR METHODS---
174
175	//---ATTRIBUTES---
176
177	/**
178	* This holds the current keys for
179	* the hosts we're authenticating
180	*/
181	private HashMap _keys = new HashMap();
182
183	/**
184	* The length of our keys
185	*/
186	private int _keylen;
187
188	/**
189	* This holds a reference to the
190	* system logger that is being used.
191	*/
192	private Logger _logger = ReferenceManager.getInstance().getLogger();
193
194	/**
195	* This is the friendly identifier of the
196	* component this class is running in.
197	* eg, a Filter may be called "filter1",
198	* If this class does not have an owning
199	* component, a name from the configuration
200	* can be placed here. This name could also
201	* be changed to null for utility classes.
202	*/
203	private String _name = FilterMain.NAME;
204
205	//---STATIC ATTRIBUTES---
206
207	/**
208	* A reference to the single instance of this class
209	*/
210	private static KeyManager _instance;
211
212	}