/**
*
* Copyright 2003-2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.geronimo.security.realm.providers;
import java.io.Serializable;
import java.util.Map;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Iterator;
import javax.security.auth.Subject;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.callback.NameCallback;
import javax.security.auth.login.LoginException;
import javax.security.auth.login.FailedLoginException;
import javax.security.auth.spi.LoginModule;
/**
* Tracks the number of recent login failures for each user, and starts
* rejecting login attemps if the number of failures in a certain period for a
* particular user gets too high. The period, number of failures, and lockout
* duration are configurable, but default to 5 failures in 5 minutes cause all
* subsequent attemps to fail for 30 minutes.
*
* This module does not write any Principals into the Subject.
*
* To enable this login module, set your primary login module and any other
* login modules to REQUIRED or OPTIONAL, and list this module in last place,
* set to REQUISITE.
*
* The parameters used by this module are:
* <ul>
* <li><b>failureCount</b> - The number of failures to allow before subsequent
* login attempts automatically fail</li>
* <li><b>failurePeriodSecs</b> - The window of time the failures must occur
* in in order to cause the lockout</li>
* <li><b>lockoutDurationSecs</b> - The duration of a lockout caused by
* exceeding the failureCount in
* failurePeriodSecs.</li>
* </ul>
*
* @version $Rev$ $Date$
*/
public class RepeatedFailureLockoutLoginModule implements LoginModule {
public static final String FAILURE_COUNT_OPTION = "failureCount";
public static final String FAILURE_PERIOD_OPTION = "failurePeriodSecs";
public static final String LOCKOUT_DURATION_OPTION = "lockoutDurationSecs";
private static final HashMap userData = new HashMap();
private CallbackHandler handler;
private String username;
private int failureCount = 5;
private int failurePeriod = 5 * 60 * 1000;
private int lockoutDuration = 30 * 60 * 1000;
/**
* Reads the configuration settings for this module.
*/
public void initialize(Subject subject, CallbackHandler callbackHandler,
Map sharedState, Map options) {
String fcString = (String) options.get(FAILURE_COUNT_OPTION);
if(fcString != null) {
fcString = fcString.trim();
if(!fcString.equals("")) {
failureCount = Integer.parseInt(fcString);
}
}
String fpString = (String) options.get(FAILURE_PERIOD_OPTION);
if(fpString != null) {
fpString = fpString.trim();
if(!fpString.equals("")) {
failurePeriod = Integer.parseInt(fpString) * 1000;
}
}
String ldString = (String) options.get(LOCKOUT_DURATION_OPTION);
if(ldString != null) {
ldString = ldString.trim();
if(!ldString.equals("")) {
lockoutDuration = Integer.parseInt(ldString) * 1000;
}
}
handler = callbackHandler;
}
/**
* Checks whether the user should be or has been locked out.
*/
public boolean login() throws LoginException {
NameCallback user = new NameCallback("User name:");
Callback[] callbacks = new Callback[]{user};
try {
handler.handle(callbacks);
} catch (Exception e) {
throw new LoginException("Unable to process callback: "+e);
}
if(callbacks.length != 1) {
throw new IllegalStateException("Number of callbacks changed by server!");
}
user = (NameCallback) callbacks[0];
username = user.getName();
if(username != null) {
LoginHistory history;
synchronized (userData) {
history = (LoginHistory) userData.get(username);
}
if(history != null && !history.isLoginAllowed(lockoutDuration, failurePeriod, failureCount)) {
username = null;
throw new FailedLoginException("Maximum login failures exceeded; try again later");
}
} else {
return false; // it's a fake login, ignore this module
}
return true;
}
/**
* This module does nothing if a login succeeds.
*/
public boolean commit() throws LoginException {
return username != null;
}
/**
* Notes that (and when) a login failure occured, used to calculate
* whether the user should be locked out.
*/
public boolean abort() throws LoginException {
if(username != null) { //work around initial "fake" login
LoginHistory history;
synchronized (userData) {
history = (LoginHistory) userData.get(username);
if(history == null) {
history = new LoginHistory(username);
userData.put(username, history);
}
}
history.addFailure();
username = null;
return true;
} else {
return false;
}
}
/**
* This module does nothing on a logout.
*/
public boolean logout() throws LoginException {
username = null;
handler = null;
return true;
}
/**
* Tracks failure attempts for a user, and calculates lockout
* status and expiry, etc.
*/
private static class LoginHistory implements Serializable {
private String user;
private LinkedList data = new LinkedList();
private long lockExpires = -1;
public LoginHistory(String user) {
this.user = user;
}
public String getUser() {
return user;
}
/**
* Cleans up the failure history and then calculates whether this user
* is locked out or not.
*/
public synchronized boolean isLoginAllowed(int lockoutLengthMillis, int failureAgeMillis, int maxFailures) {
long now = System.currentTimeMillis();
cleanup(now - failureAgeMillis);
if(lockExpires > now) {
return false;
}
if(data.size() >= maxFailures) {
lockExpires = ((Long)data.getLast()).longValue() + lockoutLengthMillis;
if(lockExpires > now) {
return false;
}
}
return true;
}
/**
* Notes that a failure occured.
*/
public synchronized void addFailure() {
data.add(new Long(System.currentTimeMillis()));
}
/**
* Cleans up all failure records outside the window of time we care
* about.
*/
public synchronized void cleanup(long ignoreOlderThan) {
for (Iterator it = data.iterator(); it.hasNext();) {
Long time = (Long) it.next();
if(time.longValue() < ignoreOlderThan) {
it.remove();
} else {
break;
}
}
}
}
}