server/ACL/ACL.java

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

//---IMPORTS---
import uk.org.iscream.cms.server.util.*;
import java.util.ArrayList;
import java.net.InetAddress;
import java.io.Serializable;

/**
 * Access Control List for use primarily
 * with the ACLServerSocket. It could, however
 * have other uses as it has a fairly generic
 * behaviour. Rules are added using the add
 * method, and then checks can be made using
 * the relevant check method.
 *
 * @author  $Author$
 * @version $Id$
 */
public class ACL implements Serializable {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision$";
    
    /**
     * static to be used when adding an ALLOW rule to the ACL.
     */
    public static final boolean ALLOW = true;
    
    /**
     * static to be used when adding a DENY rule to the ACL.
     */
    public static final boolean DENY = false;

//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Construct a new Access Control List. The default
     * mode is to ALLOW anything that isn't explicitly
     * blocked by a rule.
     */
    public ACL() {
        // default to ACL.ALLOW
        this(ACL.ALLOW);
    }
    
    /**
     * Construct a new Access Control List with a given
     * default mode. This mode specifies what should
     * happen if a check does not match any rules.
     *
     * @param defaultMode the default mode for non-matched checks
     */
    public ACL(boolean defaultMode) {
        _defaultMode = defaultMode;
    }

//---PUBLIC METHODS---

    /**
     * Add a new rule to the ACL immediately after the
     * previous rule. The rule can either be an ACL.ALLOW
     * rule, or an ACL.DENY rule. The expression can
     * contain a wildcard (a * only). Rules can only be
     * added to the end of the list.
     *
     * param allow whether this is an ALLOW or DENY rule
     * param expression what this rule matches using wildcards
     */
    public void add(boolean allow, String expression) {
        _acl.add(new ACLRule(allow, expression));
    }
    
    /**
     * Check to see if a string is permitted by the
     * ACL. Useful for testing, and non-Socket uses
     * of this class.
     *
     * @param address the string to check
     * @return whether the address was permitted by the ACL
     */
    public boolean check(String address) {
        for(int i=0; i < _acl.size(); i++) {
            ACLRule rule = (ACLRule) _acl.get(i);
            if(StringUtils.wildcardCheck(address, rule._expression)) {
                return rule._allow;
            }
        }
        return _defaultMode;
    }
    
    /**
     * Check to see if an InetAddress is permitted
     * by the ACL. Perfect for Socket uses of this
     * class. It should be made clear that this will
     * check both the hostname AND IP address against
     * each rule in turn. The hostname will always be
     * checked BEFORE the IP address.
     *
     * @param address the InetAddress to check
     * @return whether the InetAddress was permitted by the ACL
     */
    public boolean check(InetAddress address) {
        for(int i=0; i < _acl.size(); i++) {
            ACLRule rule = (ACLRule) _acl.get(i);
            if(StringUtils.wildcardCheck(address.getHostName(), rule._expression)) {
                return rule._allow;
            }
            if(StringUtils.wildcardCheck(address.getHostAddress(), rule._expression)) {
                return rule._allow;
            }
        }
        return _defaultMode;
    }
    
    /**
     * Gets the ACL as a String for debugging.
     *
     * @return A String representation of this ACL.
     */
    public String getStringACL() {
        String acl = "";
        for(int i=0; i < _acl.size(); i++) {
            ACLRule rule = (ACLRule) _acl.get(i);
            if(rule._allow) {
                acl += "ALLOW:" + rule._expression + " ";
            }
            else {
                acl += "DENY:" + rule._expression + " ";
            }
        }
        if(_defaultMode) {
            acl += "DEFAULT:ALLOW";
        }
        else {
            acl += "DEFAULT:DENY";
        }
        return acl;
    }
    
    /**
     * 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.FormatName 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 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 = null;
    
    /**
     * The ACL is stored in this ArrayList.
     */
    private ArrayList _acl = new ArrayList();
    
    /**
     * The default mode of this ACL.
     */
    private boolean _defaultMode;

//---STATIC ATTRIBUTES---

//---INNER CLASSES---

    /**
     * Wrapper class for an ACL rule.
     */
    private class ACLRule implements Serializable {
        
        /**
         * Construct an ACL rule.
         *
         * @param allow whether this is an ALLOW or DENY rule
         * @param expression what this rule matches
         */
        private ACLRule(boolean allow, String expression) {
            _allow = allow;
            _expression = expression;
        }
        
        /**
         * Whether this is an ALLOW or DENY rule.
         */
        private boolean _allow;
        
        /**
         * What this rule matches.
         */
        private String _expression;
        
    }

}
Revision:	1.4
Committed:	Sun Dec 23 00:29:33 2001 UTC (23 years, 10 months ago) by tdb
Branch:	MAIN
Changes since 1.3:	+3 -2 lines
Log Message:	Added serialization support to the ACL class. Also added testing of this feature to the ACLTest class, which confirms it works nicely :-)
#	Content
1	//---PACKAGE DECLARATION---
2	//package uk.org.iscream.cms.server.util;
3
4	//---IMPORTS---
5	import uk.org.iscream.cms.server.util.*;
6	import java.util.ArrayList;
7	import java.net.InetAddress;
8	import java.io.Serializable;
9
10	/**
11	* Access Control List for use primarily
12	* with the ACLServerSocket. It could, however
13	* have other uses as it has a fairly generic
14	* behaviour. Rules are added using the add
15	* method, and then checks can be made using
16	* the relevant check method.
17	*
18	* @author $Author$
19	* @version $Id$
20	*/
21	public class ACL implements Serializable {
22
23	//---FINAL ATTRIBUTES---
24
25	/**
26	* The current CVS revision of this class
27	*/
28	public static final String REVISION = "$Revision$";
29
30	/**
31	* static to be used when adding an ALLOW rule to the ACL.
32	*/
33	public static final boolean ALLOW = true;
34
35	/**
36	* static to be used when adding a DENY rule to the ACL.
37	*/
38	public static final boolean DENY = false;
39
40	//---STATIC METHODS---
41
42	//---CONSTRUCTORS---
43
44	/**
45	* Construct a new Access Control List. The default
46	* mode is to ALLOW anything that isn't explicitly
47	* blocked by a rule.
48	*/
49	public ACL() {
50	// default to ACL.ALLOW
51	this(ACL.ALLOW);
52	}
53
54	/**
55	* Construct a new Access Control List with a given
56	* default mode. This mode specifies what should
57	* happen if a check does not match any rules.
58	*
59	* @param defaultMode the default mode for non-matched checks
60	*/
61	public ACL(boolean defaultMode) {
62	_defaultMode = defaultMode;
63	}
64
65	//---PUBLIC METHODS---
66
67	/**
68	* Add a new rule to the ACL immediately after the
69	* previous rule. The rule can either be an ACL.ALLOW
70	* rule, or an ACL.DENY rule. The expression can
71	* contain a wildcard (a * only). Rules can only be
72	* added to the end of the list.
73	*
74	* param allow whether this is an ALLOW or DENY rule
75	* param expression what this rule matches using wildcards
76	*/
77	public void add(boolean allow, String expression) {
78	_acl.add(new ACLRule(allow, expression));
79	}
80
81	/**
82	* Check to see if a string is permitted by the
83	* ACL. Useful for testing, and non-Socket uses
84	* of this class.
85	*
86	* @param address the string to check
87	* @return whether the address was permitted by the ACL
88	*/
89	public boolean check(String address) {
90	for(int i=0; i < _acl.size(); i++) {
91	ACLRule rule = (ACLRule) _acl.get(i);
92	if(StringUtils.wildcardCheck(address, rule._expression)) {
93	return rule._allow;
94	}
95	}
96	return _defaultMode;
97	}
98
99	/**
100	* Check to see if an InetAddress is permitted
101	* by the ACL. Perfect for Socket uses of this
102	* class. It should be made clear that this will
103	* check both the hostname AND IP address against
104	* each rule in turn. The hostname will always be
105	* checked BEFORE the IP address.
106	*
107	* @param address the InetAddress to check
108	* @return whether the InetAddress was permitted by the ACL
109	*/
110	public boolean check(InetAddress address) {
111	for(int i=0; i < _acl.size(); i++) {
112	ACLRule rule = (ACLRule) _acl.get(i);
113	if(StringUtils.wildcardCheck(address.getHostName(), rule._expression)) {
114	return rule._allow;
115	}
116	if(StringUtils.wildcardCheck(address.getHostAddress(), rule._expression)) {
117	return rule._allow;
118	}
119	}
120	return _defaultMode;
121	}
122
123	/**
124	* Gets the ACL as a String for debugging.
125	*
126	* @return A String representation of this ACL.
127	*/
128	public String getStringACL() {
129	String acl = "";
130	for(int i=0; i < _acl.size(); i++) {
131	ACLRule rule = (ACLRule) _acl.get(i);
132	if(rule._allow) {
133	acl += "ALLOW:" + rule._expression + " ";
134	}
135	else {
136	acl += "DENY:" + rule._expression + " ";
137	}
138	}
139	if(_defaultMode) {
140	acl += "DEFAULT:ALLOW";
141	}
142	else {
143	acl += "DEFAULT:DENY";
144	}
145	return acl;
146	}
147
148	/**
149	* Overrides the {@link java.lang.Object#toString() Object.toString()}
150	* method to provide clean logging (every class should have this).
151	*
152	* This uses the uk.org.iscream.cms.server.util.FormatName class
153	* to format the toString()
154	*
155	* @return the name of this class and its CVS revision
156	*/
157	public String toString() {
158	return FormatName.getName(
159	_name,
160	getClass().getName(),
161	REVISION);
162	}
163
164	//---PRIVATE METHODS---
165
166	//---ACCESSOR/MUTATOR METHODS---
167
168	//---ATTRIBUTES---
169
170	/**
171	* This is the friendly identifier of the
172	* component this class is running in.
173	* eg, a Filter may be called "filter1",
174	* If this class does not have an owning
175	* component, a name from the configuration
176	* can be placed here. This name could also
177	* be changed to null for utility classes.
178	*/
179	private String _name = null;
180
181	/**
182	* The ACL is stored in this ArrayList.
183	*/
184	private ArrayList _acl = new ArrayList();
185
186	/**
187	* The default mode of this ACL.
188	*/
189	private boolean _defaultMode;
190
191	//---STATIC ATTRIBUTES---
192
193	//---INNER CLASSES---
194
195	/**
196	* Wrapper class for an ACL rule.
197	*/
198	private class ACLRule implements Serializable {
199
200	/**
201	* Construct an ACL rule.
202	*
203	* @param allow whether this is an ALLOW or DENY rule
204	* @param expression what this rule matches
205	*/
206	private ACLRule(boolean allow, String expression) {
207	_allow = allow;
208	_expression = expression;
209	}
210
211	/**
212	* Whether this is an ALLOW or DENY rule.
213	*/
214	private boolean _allow;
215
216	/**
217	* What this rule matches.
218	*/
219	private String _expression;
220
221	}
222
223	}