/*
 * Copyright (c) 2000, 2017 Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2021 Contributors to the Eclipse Foundation
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

/*
 * @(#)UserRepositoryImpl.java	1.11 06/28/07
 */

package com.sun.messaging.jmq.jmsserver.auth.jaas;

import java.util.*;
import javax.security.auth.Subject;
import javax.security.auth.Refreshable;
import javax.security.auth.Destroyable;
import javax.security.auth.login.LoginContext;
import javax.security.auth.login.LoginException;
import com.sun.messaging.jmq.util.log.Logger;
import com.sun.messaging.jmq.util.StringUtil;
import com.sun.messaging.jmq.jmsserver.Globals;
import com.sun.messaging.jmq.jmsserver.Broker;
import com.sun.messaging.jmq.jmsserver.auth.AccessController;
import com.sun.messaging.jmq.jmsserver.resources.BrokerResources;
import com.sun.messaging.jmq.auth.api.server.model.*;

/**
 * MQ JAAS user repository plugin
 */
public class UserRepositoryImpl implements UserRepository {
    private static boolean DEBUG = false;

    public static final String TYPE = "jaas";

    public static final String PROP_NAME_SUFFIX = ".name";
    public static final String SUBJECT_HELPER_SUFFIX = ".subjectHelperClass";
    public static final String SUBJECT_HELPER_PROPS_SUFFIX = ".subjectHelperClass.props";
    public static final String SUBJECT_HELPER_EMBEDDED_PROP = Globals.IMQ + ".embedded";
    public static final String SUBJECT_HELPER_JMSRA_MANAGED_PROP = Globals.JMSRA_MANAGED_PROPERTY;

    private Logger logger = Globals.getLogger();

    private String authType = null;
    private Properties authProps = null;
    private String name = null;
    private SubjectHelper subjectHelper = null;

    private LoginContext lc = null;

    private Object lock = new Object();
    private boolean login = false;
    private boolean logout = false;

    @Override
    public String getType() {
        return TYPE;
    }

    @Override
    public void open(String authType, Properties authProperties, Refreshable cacheData) throws LoginException {
        this.authType = authType;
        this.authProps = authProperties;

        String rep = authProps.getProperty(AccessController.PROP_AUTHENTICATION_PREFIX + authType + AccessController.PROP_USER_REPOSITORY_SUFFIX);
        if (rep == null) {
            throw new LoginException(Globals.getBrokerResources().getKString(BrokerResources.X_USER_REPOSITORY_NOT_DEFINED, authType));
        }
        if (!rep.equals(TYPE)) {
            String[] args = { rep, TYPE, this.getClass().getName() };
            throw new LoginException(Globals.getBrokerResources().getKString(BrokerResources.X_REPOSITORY_TYPE_MISMATCH, args));
        }
        String prefix = AccessController.PROP_USER_REPOSITORY_PREFIX + rep;
        name = authProps.getProperty(prefix + PROP_NAME_SUFFIX);
        if (name == null) {
            throw new LoginException(Globals.getBrokerResources().getKString(BrokerResources.X_JAAS_NAME_INDEX_NOT_DEFINED));
        }
        String subjectHelperc = authProps.getProperty(prefix + SUBJECT_HELPER_SUFFIX);
        if (subjectHelperc != null) {
            try {
                subjectHelper = (SubjectHelper) Class.forName(subjectHelperc).newInstance();
                String pstr = authProps.getProperty(prefix + SUBJECT_HELPER_PROPS_SUFFIX);
                Properties props = new Properties();
                props = StringUtil.toProperties(pstr, props);
                if (Broker.isInProcess()) {
                    props.setProperty(SUBJECT_HELPER_EMBEDDED_PROP, "true");
                }
                if (Globals.isJMSRAManagedBroker()) {
                    props.setProperty(SUBJECT_HELPER_JMSRA_MANAGED_PROP, "true");
                }
                subjectHelper.init(name, props, null);
            } catch (Exception e) {
                logger.logStack(logger.ERROR, "Unable to instantiate class " + subjectHelperc, e);
                throw new LoginException(e.getMessage());
            }
        }
        if (DEBUG) {
            logger.log(logger.INFO, "Using JAAS authentication " + name + (subjectHelperc == null ? "" : " with subject helper class " + subjectHelperc));
        }
    }

    /**
     * Find the user in the repository and compare the credential with the user's credential
     *
     * @param user the user name
     * @param credential password (String type) for "basic" is the password
     * @param extra null for basic, nonce if digest
     * @param matchType must be "basic"
     *
     * @return the authenticated Subject <BR>
     * null if no match found <BR>
     *
     * @exception LoginException
     */
    @Override
    public Subject findMatch(String user, Object credential, Object extra, String matchType) throws LoginException {
        if (matchType != null && matchType.equals(AccessController.AUTHTYPE_BASIC)) {
            return basicFindMatch(user, (String) credential);
        }
        String matchtyp = (matchType == null) ? "null" : matchType;
        String[] args = { matchtyp, authType, getType(), AccessController.AUTHTYPE_BASIC };
        throw new LoginException(Globals.getBrokerResources().getKString(BrokerResources.X_UNSUPPORTED_USER_REPOSITORY_MATCHTYPE, args));
    }

    private Subject basicFindMatch(String user, String userpwd) throws LoginException {
        if (DEBUG) {
            logger.log(Logger.DEBUG, "Authentication type " + AccessController.AUTHTYPE_BASIC + " - " + user + ":" + userpwd);
        }
        CallbackHandlerImpl cbh = new CallbackHandlerImpl(authProps, user, userpwd);
        Subject sub = null;
        if (subjectHelper != null) {
            try {
                sub = subjectHelper.makeSubject(user, userpwd);
            } catch (Exception e) {
                String emsg = "Failed to make subject of user " + user;
                logger.logStack(Logger.ERROR, emsg, e);
                LoginException ex = new LoginException(emsg);
                ex.initCause(e);
                throw ex;
            }
        }
        if (sub != null) {
            lc = new LoginContext(name, sub, cbh);
        } else {
            lc = new LoginContext(name, cbh);
        }
        synchronized (lock) {
            if (logout) {
                throw new LoginException(Globals.getBrokerResources().getKString(BrokerResources.X_CONNECTION_LOGGEDOUT));
            }
            lc.login();
            login = true;
            cbh.destroy();
            Subject subject = lc.getSubject();
            // XXX ?
            Set creds = subject.getPrivateCredentials();
            Iterator itr = creds.iterator();
            Object cred = null;
            while (itr.hasNext()) {
                try {
                    cred = itr.next();
                    if (cred == null) {
                        continue;
                    }
                    if (cred instanceof Destroyable && !((Destroyable) cred).isDestroyed()) {
                        ((Destroyable) cred).destroy();
                    }
                } catch (Exception e) {
                    logger.log(logger.WARNING, "XXX Unable to destroy private credential:" + cred.getClass().getName() + " for " + user);
                }
            }
            return subject;
        }
    }

    @Override
    public Refreshable getCacheData() {
        if (subjectHelper == null) {
            return null;
        }
        return subjectHelper.getCacheData();
    }

    @Override
    public void close() throws LoginException {
        synchronized (lock) {
            if (!logout) {
                if (login) {
                    lc.logout();
                    logout = true;
                }
            }
        }
    }

}
