Source Code Cross Referenced for JDBCRealm.java in  » Sevlet-Container » apache-tomcat-6.0.14 » org » apache » catalina » realm » Java Source Code / Java DocumentationJava Source Code and Java Documentation

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Java Source Code / Java Documentation » Sevlet Container » apache tomcat 6.0.14 » org.apache.catalina.realm 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         * Licensed to the Apache Software Foundation (ASF) under one or more
003:         * contributor license agreements.  See the NOTICE file distributed with
004:         * this work for additional information regarding copyright ownership.
005:         * The ASF licenses this file to You under the Apache License, Version 2.0
006:         * (the "License"); you may not use this file except in compliance with
007:         * the License.  You may obtain a copy of the License at
008:         * 
009:         *      http://www.apache.org/licenses/LICENSE-2.0
010:         * 
011:         * Unless required by applicable law or agreed to in writing, software
012:         * distributed under the License is distributed on an "AS IS" BASIS,
013:         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014:         * See the License for the specific language governing permissions and
015:         * limitations under the License.
016:         */
017:
018:        package org.apache.catalina.realm;
019:
020:        import java.security.Principal;
021:        import java.sql.Connection;
022:        import java.sql.Driver;
023:        import java.sql.PreparedStatement;
024:        import java.sql.ResultSet;
025:        import java.sql.SQLException;
026:        import java.util.ArrayList;
027:        import java.util.Properties;
028:
029:        import org.apache.catalina.LifecycleException;
030:        import org.apache.catalina.util.StringManager;
031:
032:        /**
033:         *
034:         * Implmentation of <b>Realm</b> that works with any JDBC supported database.
035:         * See the JDBCRealm.howto for more details on how to set up the database and
036:         * for configuration options.
037:         *
038:         * <p><strong>TODO</strong> - Support connection pooling (including message
039:         * format objects) so that <code>authenticate()</code>,
040:         * <code>getPassword()</code> and <code>authenticate()</code> do not have to be
041:         * synchronized and would fix the ugly connection logic. </p>
042:         *
043:         * @author Craig R. McClanahan
044:         * @author Carson McDonald
045:         * @author Ignacio Ortega
046:         * @version $Revision: 543691 $ $Date: 2007-06-02 03:37:08 +0200 (sam., 02 juin 2007) $
047:         */
048:
049:        public class JDBCRealm extends RealmBase {
050:
051:            // ----------------------------------------------------- Instance Variables
052:
053:            /**
054:             * The connection username to use when trying to connect to the database.
055:             */
056:            protected String connectionName = null;
057:
058:            /**
059:             * The connection URL to use when trying to connect to the database.
060:             */
061:            protected String connectionPassword = null;
062:
063:            /**
064:             * The connection URL to use when trying to connect to the database.
065:             */
066:            protected String connectionURL = null;
067:
068:            /**
069:             * The connection to the database.
070:             */
071:            protected Connection dbConnection = null;
072:
073:            /**
074:             * Instance of the JDBC Driver class we use as a connection factory.
075:             */
076:            protected Driver driver = null;
077:
078:            /**
079:             * The JDBC driver to use.
080:             */
081:            protected String driverName = null;
082:
083:            /**
084:             * Descriptive information about this Realm implementation.
085:             */
086:            protected static final String info = "org.apache.catalina.realm.JDBCRealm/1.0";
087:
088:            /**
089:             * Descriptive information about this Realm implementation.
090:             */
091:            protected static final String name = "JDBCRealm";
092:
093:            /**
094:             * The PreparedStatement to use for authenticating users.
095:             */
096:            protected PreparedStatement preparedCredentials = null;
097:
098:            /**
099:             * The PreparedStatement to use for identifying the roles for
100:             * a specified user.
101:             */
102:            protected PreparedStatement preparedRoles = null;
103:
104:            /**
105:             * The column in the user role table that names a role
106:             */
107:            protected String roleNameCol = null;
108:
109:            /**
110:             * The string manager for this package.
111:             */
112:            protected static final StringManager sm = StringManager
113:                    .getManager(Constants.Package);
114:
115:            /**
116:             * The column in the user table that holds the user's credintials
117:             */
118:            protected String userCredCol = null;
119:
120:            /**
121:             * The column in the user table that holds the user's name
122:             */
123:            protected String userNameCol = null;
124:
125:            /**
126:             * The table that holds the relation between user's and roles
127:             */
128:            protected String userRoleTable = null;
129:
130:            /**
131:             * The table that holds user data.
132:             */
133:            protected String userTable = null;
134:
135:            // ------------------------------------------------------------- Properties
136:
137:            /**
138:             * Return the username to use to connect to the database.
139:             *
140:             */
141:            public String getConnectionName() {
142:                return connectionName;
143:            }
144:
145:            /**
146:             * Set the username to use to connect to the database.
147:             *
148:             * @param connectionName Username
149:             */
150:            public void setConnectionName(String connectionName) {
151:                this .connectionName = connectionName;
152:            }
153:
154:            /**
155:             * Return the password to use to connect to the database.
156:             *
157:             */
158:            public String getConnectionPassword() {
159:                return connectionPassword;
160:            }
161:
162:            /**
163:             * Set the password to use to connect to the database.
164:             *
165:             * @param connectionPassword User password
166:             */
167:            public void setConnectionPassword(String connectionPassword) {
168:                this .connectionPassword = connectionPassword;
169:            }
170:
171:            /**
172:             * Return the URL to use to connect to the database.
173:             *
174:             */
175:            public String getConnectionURL() {
176:                return connectionURL;
177:            }
178:
179:            /**
180:             * Set the URL to use to connect to the database.
181:             *
182:             * @param connectionURL The new connection URL
183:             */
184:            public void setConnectionURL(String connectionURL) {
185:                this .connectionURL = connectionURL;
186:            }
187:
188:            /**
189:             * Return the JDBC driver that will be used.
190:             *
191:             */
192:            public String getDriverName() {
193:                return driverName;
194:            }
195:
196:            /**
197:             * Set the JDBC driver that will be used.
198:             *
199:             * @param driverName The driver name
200:             */
201:            public void setDriverName(String driverName) {
202:                this .driverName = driverName;
203:            }
204:
205:            /**
206:             * Return the column in the user role table that names a role.
207:             *
208:             */
209:            public String getRoleNameCol() {
210:                return roleNameCol;
211:            }
212:
213:            /**
214:             * Set the column in the user role table that names a role.
215:             *
216:             * @param roleNameCol The column name
217:             */
218:            public void setRoleNameCol(String roleNameCol) {
219:                this .roleNameCol = roleNameCol;
220:            }
221:
222:            /**
223:             * Return the column in the user table that holds the user's credentials.
224:             *
225:             */
226:            public String getUserCredCol() {
227:                return userCredCol;
228:            }
229:
230:            /**
231:             * Set the column in the user table that holds the user's credentials.
232:             *
233:             * @param userCredCol The column name
234:             */
235:            public void setUserCredCol(String userCredCol) {
236:                this .userCredCol = userCredCol;
237:            }
238:
239:            /**
240:             * Return the column in the user table that holds the user's name.
241:             *
242:             */
243:            public String getUserNameCol() {
244:                return userNameCol;
245:            }
246:
247:            /**
248:             * Set the column in the user table that holds the user's name.
249:             *
250:             * @param userNameCol The column name
251:             */
252:            public void setUserNameCol(String userNameCol) {
253:                this .userNameCol = userNameCol;
254:            }
255:
256:            /**
257:             * Return the table that holds the relation between user's and roles.
258:             *
259:             */
260:            public String getUserRoleTable() {
261:                return userRoleTable;
262:            }
263:
264:            /**
265:             * Set the table that holds the relation between user's and roles.
266:             *
267:             * @param userRoleTable The table name
268:             */
269:            public void setUserRoleTable(String userRoleTable) {
270:                this .userRoleTable = userRoleTable;
271:            }
272:
273:            /**
274:             * Return the table that holds user data..
275:             *
276:             */
277:            public String getUserTable() {
278:                return userTable;
279:            }
280:
281:            /**
282:             * Set the table that holds user data.
283:             *
284:             * @param userTable The table name
285:             */
286:            public void setUserTable(String userTable) {
287:                this .userTable = userTable;
288:            }
289:
290:            // --------------------------------------------------------- Public Methods
291:
292:            /**
293:             * Return the Principal associated with the specified username and
294:             * credentials, if there is one; otherwise return <code>null</code>.
295:             *
296:             * If there are any errors with the JDBC connection, executing
297:             * the query or anything we return null (don't authenticate). This
298:             * event is also logged, and the connection will be closed so that
299:             * a subsequent request will automatically re-open it.
300:             *
301:             *
302:             * @param username Username of the Principal to look up
303:             * @param credentials Password or other credentials to use in
304:             *  authenticating this username
305:             */
306:            public synchronized Principal authenticate(String username,
307:                    String credentials) {
308:
309:                // Number of tries is the numebr of attempts to connect to the database
310:                // during this login attempt (if we need to open the database)
311:                // This needs rewritten wuth better pooling support, the existing code
312:                // needs signature changes since the Prepared statements needs cached
313:                // with the connections.
314:                // The code below will try twice if there is a SQLException so the
315:                // connection may try to be opened again. On normal conditions (including
316:                // invalid login - the above is only used once.
317:                int numberOfTries = 2;
318:                while (numberOfTries > 0) {
319:                    try {
320:
321:                        // Ensure that we have an open database connection
322:                        open();
323:
324:                        // Acquire a Principal object for this user
325:                        Principal principal = authenticate(dbConnection,
326:                                username, credentials);
327:
328:                        // Return the Principal (if any)
329:                        return (principal);
330:
331:                    } catch (SQLException e) {
332:
333:                        // Log the problem for posterity
334:                        containerLog.error(sm.getString("jdbcRealm.exception"),
335:                                e);
336:
337:                        // Close the connection so that it gets reopened next time
338:                        if (dbConnection != null)
339:                            close(dbConnection);
340:
341:                    }
342:
343:                    numberOfTries--;
344:                }
345:
346:                // Worst case scenario
347:                return null;
348:
349:            }
350:
351:            // -------------------------------------------------------- Package Methods
352:
353:            // ------------------------------------------------------ Protected Methods
354:
355:            /**
356:             * Return the Principal associated with the specified username and
357:             * credentials, if there is one; otherwise return <code>null</code>.
358:             *
359:             * @param dbConnection The database connection to be used
360:             * @param username Username of the Principal to look up
361:             * @param credentials Password or other credentials to use in
362:             *  authenticating this username
363:             */
364:            public synchronized Principal authenticate(Connection dbConnection,
365:                    String username, String credentials) {
366:
367:                // No user - can't possibly authenticate
368:                if (username == null) {
369:                    return (null);
370:                }
371:
372:                // Look up the user's credentials
373:                String dbCredentials = getPassword(username);
374:
375:                // Validate the user's credentials
376:                boolean validated = false;
377:                if (hasMessageDigest()) {
378:                    // Hex hashes should be compared case-insensitive
379:                    validated = (digest(credentials)
380:                            .equalsIgnoreCase(dbCredentials));
381:                } else {
382:                    validated = (digest(credentials).equals(dbCredentials));
383:                }
384:
385:                if (validated) {
386:                    if (containerLog.isTraceEnabled())
387:                        containerLog.trace(sm.getString(
388:                                "jdbcRealm.authenticateSuccess", username));
389:                } else {
390:                    if (containerLog.isTraceEnabled())
391:                        containerLog.trace(sm.getString(
392:                                "jdbcRealm.authenticateFailure", username));
393:                    return (null);
394:                }
395:
396:                ArrayList<String> roles = getRoles(username);
397:
398:                // Create and return a suitable Principal for this user
399:                return (new GenericPrincipal(this , username, credentials, roles));
400:
401:            }
402:
403:            /**
404:             * Close the specified database connection.
405:             *
406:             * @param dbConnection The connection to be closed
407:             */
408:            protected void close(Connection dbConnection) {
409:
410:                // Do nothing if the database connection is already closed
411:                if (dbConnection == null)
412:                    return;
413:
414:                // Close our prepared statements (if any)
415:                try {
416:                    preparedCredentials.close();
417:                } catch (Throwable f) {
418:                    ;
419:                }
420:                this .preparedCredentials = null;
421:
422:                try {
423:                    preparedRoles.close();
424:                } catch (Throwable f) {
425:                    ;
426:                }
427:                this .preparedRoles = null;
428:
429:                // Close this database connection, and log any errors
430:                try {
431:                    dbConnection.close();
432:                } catch (SQLException e) {
433:                    containerLog.warn(sm.getString("jdbcRealm.close"), e); // Just log it here
434:                } finally {
435:                    this .dbConnection = null;
436:                }
437:
438:            }
439:
440:            /**
441:             * Return a PreparedStatement configured to perform the SELECT required
442:             * to retrieve user credentials for the specified username.
443:             *
444:             * @param dbConnection The database connection to be used
445:             * @param username Username for which credentials should be retrieved
446:             *
447:             * @exception SQLException if a database error occurs
448:             */
449:            protected PreparedStatement credentials(Connection dbConnection,
450:                    String username) throws SQLException {
451:
452:                if (preparedCredentials == null) {
453:                    StringBuffer sb = new StringBuffer("SELECT ");
454:                    sb.append(userCredCol);
455:                    sb.append(" FROM ");
456:                    sb.append(userTable);
457:                    sb.append(" WHERE ");
458:                    sb.append(userNameCol);
459:                    sb.append(" = ?");
460:
461:                    if (containerLog.isDebugEnabled()) {
462:                        containerLog.debug("credentials query: "
463:                                + sb.toString());
464:                    }
465:
466:                    preparedCredentials = dbConnection.prepareStatement(sb
467:                            .toString());
468:                }
469:
470:                if (username == null) {
471:                    preparedCredentials.setNull(1, java.sql.Types.VARCHAR);
472:                } else {
473:                    preparedCredentials.setString(1, username);
474:                }
475:
476:                return (preparedCredentials);
477:            }
478:
479:            /**
480:             * Return a short name for this Realm implementation.
481:             */
482:            protected String getName() {
483:
484:                return (name);
485:
486:            }
487:
488:            /**
489:             * Return the password associated with the given principal's user name.
490:             */
491:            protected synchronized String getPassword(String username) {
492:
493:                // Look up the user's credentials
494:                String dbCredentials = null;
495:                PreparedStatement stmt = null;
496:                ResultSet rs = null;
497:
498:                // Number of tries is the numebr of attempts to connect to the database
499:                // during this login attempt (if we need to open the database)
500:                // This needs rewritten wuth better pooling support, the existing code
501:                // needs signature changes since the Prepared statements needs cached
502:                // with the connections.
503:                // The code below will try twice if there is a SQLException so the
504:                // connection may try to be opened again. On normal conditions (including
505:                // invalid login - the above is only used once.
506:                int numberOfTries = 2;
507:                while (numberOfTries > 0) {
508:                    try {
509:
510:                        // Ensure that we have an open database connection
511:                        open();
512:
513:                        try {
514:                            stmt = credentials(dbConnection, username);
515:                            rs = stmt.executeQuery();
516:
517:                            if (rs.next()) {
518:                                dbCredentials = rs.getString(1);
519:                            }
520:                            rs.close();
521:                            rs = null;
522:                            if (dbCredentials == null) {
523:                                return (null);
524:                            }
525:
526:                            dbCredentials = dbCredentials.trim();
527:                            return dbCredentials;
528:
529:                        } finally {
530:                            if (rs != null) {
531:                                try {
532:                                    rs.close();
533:                                } catch (SQLException e) {
534:                                    containerLog
535:                                            .warn(sm
536:                                                    .getString("jdbcRealm.abnormalCloseResultSet"));
537:                                }
538:                            }
539:                            dbConnection.commit();
540:                        }
541:
542:                    } catch (SQLException e) {
543:
544:                        // Log the problem for posterity
545:                        containerLog.error(sm.getString("jdbcRealm.exception"),
546:                                e);
547:
548:                        // Close the connection so that it gets reopened next time
549:                        if (dbConnection != null)
550:                            close(dbConnection);
551:
552:                    }
553:
554:                    numberOfTries--;
555:                }
556:
557:                return (null);
558:            }
559:
560:            /**
561:             * Return the Principal associated with the given user name.
562:             */
563:            protected Principal getPrincipal(String username) {
564:
565:                return (new GenericPrincipal(this , username,
566:                        getPassword(username), getRoles(username)));
567:
568:            }
569:
570:            /**
571:             * Return the roles associated with the gven user name.
572:             */
573:            protected ArrayList<String> getRoles(String username) {
574:
575:                PreparedStatement stmt = null;
576:                ResultSet rs = null;
577:
578:                // Number of tries is the numebr of attempts to connect to the database
579:                // during this login attempt (if we need to open the database)
580:                // This needs rewritten wuth better pooling support, the existing code
581:                // needs signature changes since the Prepared statements needs cached
582:                // with the connections.
583:                // The code below will try twice if there is a SQLException so the
584:                // connection may try to be opened again. On normal conditions (including
585:                // invalid login - the above is only used once.
586:                int numberOfTries = 2;
587:                while (numberOfTries > 0) {
588:                    try {
589:
590:                        // Ensure that we have an open database connection
591:                        open();
592:
593:                        try {
594:                            // Accumulate the user's roles
595:                            ArrayList<String> roleList = new ArrayList<String>();
596:                            stmt = roles(dbConnection, username);
597:                            rs = stmt.executeQuery();
598:                            while (rs.next()) {
599:                                String role = rs.getString(1);
600:                                if (null != role) {
601:                                    roleList.add(role.trim());
602:                                }
603:                            }
604:                            rs.close();
605:                            rs = null;
606:
607:                            return (roleList);
608:
609:                        } finally {
610:                            if (rs != null) {
611:                                try {
612:                                    rs.close();
613:                                } catch (SQLException e) {
614:                                    containerLog
615:                                            .warn(sm
616:                                                    .getString("jdbcRealm.abnormalCloseResultSet"));
617:                                }
618:                            }
619:                            dbConnection.commit();
620:                        }
621:
622:                    } catch (SQLException e) {
623:
624:                        // Log the problem for posterity
625:                        containerLog.error(sm.getString("jdbcRealm.exception"),
626:                                e);
627:
628:                        // Close the connection so that it gets reopened next time
629:                        if (dbConnection != null)
630:                            close(dbConnection);
631:
632:                    }
633:
634:                    numberOfTries--;
635:                }
636:
637:                return (null);
638:
639:            }
640:
641:            /**
642:             * Open (if necessary) and return a database connection for use by
643:             * this Realm.
644:             *
645:             * @exception SQLException if a database error occurs
646:             */
647:            protected Connection open() throws SQLException {
648:
649:                // Do nothing if there is a database connection already open
650:                if (dbConnection != null)
651:                    return (dbConnection);
652:
653:                // Instantiate our database driver if necessary
654:                if (driver == null) {
655:                    try {
656:                        Class clazz = Class.forName(driverName);
657:                        driver = (Driver) clazz.newInstance();
658:                    } catch (Throwable e) {
659:                        throw new SQLException(e.getMessage());
660:                    }
661:                }
662:
663:                // Open a new connection
664:                Properties props = new Properties();
665:                if (connectionName != null)
666:                    props.put("user", connectionName);
667:                if (connectionPassword != null)
668:                    props.put("password", connectionPassword);
669:                dbConnection = driver.connect(connectionURL, props);
670:                dbConnection.setAutoCommit(false);
671:                return (dbConnection);
672:
673:            }
674:
675:            /**
676:             * Release our use of this connection so that it can be recycled.
677:             *
678:             * @param dbConnection The connection to be released
679:             */
680:            protected void release(Connection dbConnection) {
681:
682:                ; // NO-OP since we are not pooling anything
683:
684:            }
685:
686:            /**
687:             * Return a PreparedStatement configured to perform the SELECT required
688:             * to retrieve user roles for the specified username.
689:             *
690:             * @param dbConnection The database connection to be used
691:             * @param username Username for which roles should be retrieved
692:             *
693:             * @exception SQLException if a database error occurs
694:             */
695:            protected synchronized PreparedStatement roles(
696:                    Connection dbConnection, String username)
697:                    throws SQLException {
698:
699:                if (preparedRoles == null) {
700:                    StringBuffer sb = new StringBuffer("SELECT ");
701:                    sb.append(roleNameCol);
702:                    sb.append(" FROM ");
703:                    sb.append(userRoleTable);
704:                    sb.append(" WHERE ");
705:                    sb.append(userNameCol);
706:                    sb.append(" = ?");
707:                    preparedRoles = dbConnection
708:                            .prepareStatement(sb.toString());
709:                }
710:
711:                preparedRoles.setString(1, username);
712:                return (preparedRoles);
713:
714:            }
715:
716:            // ------------------------------------------------------ Lifecycle Methods
717:
718:            /**
719:             *
720:             * Prepare for active use of the public methods of this Component.
721:             *
722:             * @exception LifecycleException if this component detects a fatal error
723:             *  that prevents it from being started
724:             */
725:            public void start() throws LifecycleException {
726:
727:                // Perform normal superclass initialization
728:                super .start();
729:
730:                // Validate that we can open our connection - but let tomcat
731:                // startup in case the database is temporarily unavailable
732:                try {
733:                    open();
734:                } catch (SQLException e) {
735:                    containerLog.error(sm.getString("jdbcRealm.open"), e);
736:                }
737:
738:            }
739:
740:            /**
741:             * Gracefully shut down active use of the public methods of this Component.
742:             *
743:             * @exception LifecycleException if this component detects a fatal error
744:             *  that needs to be reported
745:             */
746:            public void stop() throws LifecycleException {
747:
748:                // Perform normal superclass finalization
749:                super .stop();
750:
751:                // Close any open DB connection
752:                close(this.dbConnection);
753:
754:            }
755:
756:        }
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