jdbcrealm.java

业界著名的tomcat服务器的最新6.0的源代码。

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.catalina.realm;


import java.security.Principal;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Properties;

import org.apache.catalina.LifecycleException;
import org.apache.catalina.util.StringManager;


/**
*
* Implmentation of <b>Realm</b> that works with any JDBC supported database.
* See the JDBCRealm.howto for more details on how to set up the database and
* for configuration options.
*
* <p><strong>TODO</strong> - Support connection pooling (including message
* format objects) so that <code>authenticate()</code>,
* <code>getPassword()</code> and <code>authenticate()</code> do not have to be
* synchronized and would fix the ugly connection logic. </p>
*
* @author Craig R. McClanahan
* @author Carson McDonald
* @author Ignacio Ortega
* @version $Revision: 476979 $ $Date: 2006-11-20 00:52:52 +0100 (lun., 20 nov. 2006) $
*/

public class JDBCRealm
    extends RealmBase {


    // ----------------------------------------------------- Instance Variables


    /**
     * The connection username to use when trying to connect to the database.
     */
    protected String connectionName = null;


    /**
     * The connection URL to use when trying to connect to the database.
     */
    protected String connectionPassword = null;


    /**
     * The connection URL to use when trying to connect to the database.
     */
    protected String connectionURL = null;


    /**
     * The connection to the database.
     */
    protected Connection dbConnection = null;


    /**
     * Instance of the JDBC Driver class we use as a connection factory.
     */
    protected Driver driver = null;


    /**
     * The JDBC driver to use.
     */
    protected String driverName = null;


    /**
     * Descriptive information about this Realm implementation.
     */
    protected static final String info =
        "org.apache.catalina.realm.JDBCRealm/1.0";


    /**
     * Descriptive information about this Realm implementation.
     */
    protected static final String name = "JDBCRealm";


    /**
     * The PreparedStatement to use for authenticating users.
     */
    protected PreparedStatement preparedCredentials = null;


    /**
     * The PreparedStatement to use for identifying the roles for
     * a specified user.
     */
    protected PreparedStatement preparedRoles = null;


    /**
     * The column in the user role table that names a role
     */
    protected String roleNameCol = null;


    /**
     * The string manager for this package.
     */
    protected static final StringManager sm =
        StringManager.getManager(Constants.Package);


    /**
     * The column in the user table that holds the user's credintials
     */
    protected String userCredCol = null;


    /**
     * The column in the user table that holds the user's name
     */
    protected String userNameCol = null;


    /**
     * The table that holds the relation between user's and roles
     */
    protected String userRoleTable = null;


    /**
     * The table that holds user data.
     */
    protected String userTable = null;


    // ------------------------------------------------------------- Properties

    /**
     * Return the username to use to connect to the database.
     *
     */
    public String getConnectionName() {
        return connectionName;
    }

    /**
     * Set the username to use to connect to the database.
     *
     * @param connectionName Username
     */
    public void setConnectionName(String connectionName) {
        this.connectionName = connectionName;
    }

    /**
     * Return the password to use to connect to the database.
     *
     */
    public String getConnectionPassword() {
        return connectionPassword;
    }

    /**
     * Set the password to use to connect to the database.
     *
     * @param connectionPassword User password
     */
    public void setConnectionPassword(String connectionPassword) {
        this.connectionPassword = connectionPassword;
    }

    /**
     * Return the URL to use to connect to the database.
     *
     */
    public String getConnectionURL() {
        return connectionURL;
    }

    /**
     * Set the URL to use to connect to the database.
     *
     * @param connectionURL The new connection URL
     */
    public void setConnectionURL( String connectionURL ) {
      this.connectionURL = connectionURL;
    }

    /**
     * Return the JDBC driver that will be used.
     *
     */
    public String getDriverName() {
        return driverName;
    }

    /**
     * Set the JDBC driver that will be used.
     *
     * @param driverName The driver name
     */
    public void setDriverName( String driverName ) {
      this.driverName = driverName;
    }

    /**
     * Return the column in the user role table that names a role.
     *
     */
    public String getRoleNameCol() {
        return roleNameCol;
    }

    /**
     * Set the column in the user role table that names a role.
     *
     * @param roleNameCol The column name
     */
    public void setRoleNameCol( String roleNameCol ) {
        this.roleNameCol = roleNameCol;
    }

    /**
     * Return the column in the user table that holds the user's credentials.
     *
     */
    public String getUserCredCol() {
        return userCredCol;
    }

    /**
     * Set the column in the user table that holds the user's credentials.
     *
     * @param userCredCol The column name
     */
    public void setUserCredCol( String userCredCol ) {
       this.userCredCol = userCredCol;
    }

    /**
     * Return the column in the user table that holds the user's name.
     *
     */
    public String getUserNameCol() {
        return userNameCol;
    }

    /**
     * Set the column in the user table that holds the user's name.
     *
     * @param userNameCol The column name
     */
    public void setUserNameCol( String userNameCol ) {
       this.userNameCol = userNameCol;
    }

    /**
     * Return the table that holds the relation between user's and roles.
     *
     */
    public String getUserRoleTable() {
        return userRoleTable;
    }

    /**
     * Set the table that holds the relation between user's and roles.
     *
     * @param userRoleTable The table name
     */
    public void setUserRoleTable( String userRoleTable ) {
        this.userRoleTable = userRoleTable;
    }

    /**
     * Return the table that holds user data..
     *
     */
    public String getUserTable() {
        return userTable;
    }

    /**
     * Set the table that holds user data.
     *
     * @param userTable The table name
     */
    public void setUserTable( String userTable ) {
      this.userTable = userTable;
    }


    // --------------------------------------------------------- Public Methods


    /**
     * Return the Principal associated with the specified username and
     * credentials, if there is one; otherwise return <code>null</code>.
     *
     * If there are any errors with the JDBC connection, executing
     * the query or anything we return null (don't authenticate). This
     * event is also logged, and the connection will be closed so that
     * a subsequent request will automatically re-open it.
     *
     *
     * @param username Username of the Principal to look up
     * @param credentials Password or other credentials to use in
     *  authenticating this username
     */
    public synchronized Principal authenticate(String username, String credentials) {

        // Number of tries is the numebr of attempts to connect to the database
        // during this login attempt (if we need to open the database)
        // This needs rewritten wuth better pooling support, the existing code
        // needs signature changes since the Prepared statements needs cached
        // with the connections.
        // The code below will try twice if there is a SQLException so the
        // connection may try to be opened again. On normal conditions (including
        // invalid login - the above is only used once.
        int numberOfTries = 2;
        while (numberOfTries>0) {
            try {

                // Ensure that we have an open database connection
                open();

                // Acquire a Principal object for this user
                Principal principal = authenticate(dbConnection,
                                                   username, credentials);


                // Return the Principal (if any)
                return (principal);

            } catch (SQLException e) {

                // Log the problem for posterity
                containerLog.error(sm.getString("jdbcRealm.exception"), e);

                // Close the connection so that it gets reopened next time
                if (dbConnection != null)
                    close(dbConnection);

            }

            numberOfTries--;
        }

        // Worst case scenario
        return null;

    }


    // -------------------------------------------------------- Package Methods


    // ------------------------------------------------------ Protected Methods


    /**
     * Return the Principal associated with the specified username and
     * credentials, if there is one; otherwise return <code>null</code>.
     *
     * @param dbConnection The database connection to be used
     * @param username Username of the Principal to look up
     * @param credentials Password or other credentials to use in
     *  authenticating this username
     */
    public synchronized Principal authenticate(Connection dbConnection,
                                               String username,
                                               String credentials) {

        // No user - can't possibly authenticate
        if (username == null) {
            return (null);
        }