2 * Copyright (C) 2001, 2002 The Mir-coders group
4 * This file is part of Mir.
6 * Mir is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * Mir 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.
16 * You should have received a copy of the GNU General Public License
17 * along with Mir; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * In addition, as a special exception, The Mir-coders gives permission to link
21 * the code of this program with any library licensed under the Apache Software License,
22 * The Sun (tm) Java Advanced Imaging library (JAI), The Sun JIMI library
23 * (or with modified versions of the above that use the same license as the above),
24 * and distribute linked combinations including the two. You must obey the
25 * GNU General Public License in all respects for all of the code used other than
26 * the above mentioned libraries. If you modify this file, you may extend this
27 * exception to your version of the file, but you are not obligated to do so.
28 * If you do not wish to do so, delete this exception statement from your version.
30 package mircoders.abuse;
32 import java.util.ArrayList;
33 import java.util.Iterator;
34 import java.util.List;
36 import mir.entity.Entity;
37 import mir.session.Request;
38 import mir.util.StringRoutines;
41 * A ip-based throttling filter.
44 * Expressions have the form <time in minutes>:<posting limit>
46 public class ThrottleFilter extends AbstractFilterType {
48 public ThrottleFilter(String aName) {
52 public FilterInstance constructFilterInstance(String anExpression) throws AbuseExc {
53 List parts = StringRoutines.splitString(anExpression.trim(), ":");
55 if (parts.size()==2) {
57 final int interval = Integer.parseInt((String) parts.get(0));
58 final int limit = Integer.parseInt((String) parts.get(1));
61 throw new AbuseExc("Interval should be larger than 0");
64 throw new AbuseExc("Limit should be larger than 0");
66 final ThrottleManager manager = new ThrottleManager(interval*1000*60);
68 return new FilterInstance() {
69 public boolean test(Entity anEntity, Request aRequest) {
70 manager.addMessage(aRequest.getHeader("ip"));
71 if (manager.count(aRequest.getHeader("ip")) > limit) {
78 public String status() {
79 return Integer.toString(manager.messages.size()) + " messages";
87 throw new AbuseExc("Invalid expression: <interval>:<limit> expected");
90 throw new AbuseExc("Invalid expression: <interval>:<limit> expected");
93 private class ThrottleManager {
95 private List messages;
97 public ThrottleManager(long aHorizon) {
100 messages = new ArrayList();
103 public void flush() {
104 long limit = System.currentTimeMillis() - horizon;
106 while (messages.size()>0 && ((Message) messages.get(0)).getTime()<=limit) {
111 public void addMessage(String anIp) {
112 Message newMessage = new Message(anIp, System.currentTimeMillis());
113 messages.add(newMessage);
116 public int count(String anIp) {
120 Iterator i = messages.iterator();
121 while (i.hasNext()) {
122 Message message = (Message) i.next();
123 if (message.getIp().equals(anIp)) {
131 private class Message {
135 public Message(String anIp, long aTime) {
140 public String getIp() {
144 public long getTime() {