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: tdb $
 * @version $Id: ACL.java,v 1.5 2001/12/23 01:05:35 tdb Exp $
 */
public class ACL implements Serializable {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision: 1.5 $";
    
    /**
     * 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;
    }
    
    /**
     * Gives a String representation of this ACL.
     *
     * @return A String representation of this ACL.
     */
    public String toString() {
        StringBuffer acl = new StringBuffer();
        acl.append("{");
        for(int i=0; i < _acl.size(); i++) {
            acl.append((ACLRule) _acl.get(i));
            acl.append(",");
        }
        if(_defaultMode) {
            acl.append("DEFAULT=ALLOW");
        }
        else {
            acl.append("DEFAULT=DENY");
        }
        acl.append("}");
        return acl.toString();
    }

//---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;
        }
        
        /**
         * Returns a String representation of this rule.
         *
         * @return A String representation of this rule.
         */
        public String toString() {
            if(_allow) {
                return _expression + "=ALLOW";
            }
            else {
                return _expression + "=DENY";
            }
        }
        
        /**
         * Whether this is an ALLOW or DENY rule.
         */
        private boolean _allow;
        
        /**
         * What this rule matches.
         */
        private String _expression;
        
    }

}
Revision:	1.6
Committed:	Mon Dec 24 04:17:29 2001 UTC (22 years, 4 months ago) by tdb
Branch:	MAIN
Changes since 1.5:	+18 -10 lines
Log Message:	Creating a toString() for ACLRule, and modified the ACL toString() to make use of this. It's a bit neater I think.
#	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: tdb $
19	* @version $Id: ACL.java,v 1.5 2001/12/23 01:05:35 tdb Exp $
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: 1.5 $";
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	* Gives a String representation of this ACL.
125	*
126	* @return A String representation of this ACL.
127	*/
128	public String toString() {
129	StringBuffer acl = new StringBuffer();
130	acl.append("{");
131	for(int i=0; i < _acl.size(); i++) {
132	acl.append((ACLRule) _acl.get(i));
133	acl.append(",");
134	}
135	if(_defaultMode) {
136	acl.append("DEFAULT=ALLOW");
137	}
138	else {
139	acl.append("DEFAULT=DENY");
140	}
141	acl.append("}");
142	return acl.toString();
143	}
144
145	//---PRIVATE METHODS---
146
147	//---ACCESSOR/MUTATOR METHODS---
148
149	//---ATTRIBUTES---
150
151	/**
152	* This is the friendly identifier of the
153	* component this class is running in.
154	* eg, a Filter may be called "filter1",
155	* If this class does not have an owning
156	* component, a name from the configuration
157	* can be placed here. This name could also
158	* be changed to null for utility classes.
159	*/
160	private String _name = null;
161
162	/**
163	* The ACL is stored in this ArrayList.
164	*/
165	private ArrayList _acl = new ArrayList();
166
167	/**
168	* The default mode of this ACL.
169	*/
170	private boolean _defaultMode;
171
172	//---STATIC ATTRIBUTES---
173
174	//---INNER CLASSES---
175
176	/**
177	* Wrapper class for an ACL rule.
178	*/
179	private class ACLRule implements Serializable {
180
181	/**
182	* Construct an ACL rule.
183	*
184	* @param allow whether this is an ALLOW or DENY rule
185	* @param expression what this rule matches
186	*/
187	private ACLRule(boolean allow, String expression) {
188	_allow = allow;
189	_expression = expression;
190	}
191
192	/**
193	* Returns a String representation of this rule.
194	*
195	* @return A String representation of this rule.
196	*/
197	public String toString() {
198	if(_allow) {
199	return _expression + "=ALLOW";
200	}
201	else {
202	return _expression + "=DENY";
203	}
204	}
205
206	/**
207	* Whether this is an ALLOW or DENY rule.
208	*/
209	private boolean _allow;
210
211	/**
212	* What this rule matches.
213	*/
214	private String _expression;
215
216	}
217
218	}