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package org.glassfish.admingui.common.security;

import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.ClientResponse;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.api.client.filter.HTTPBasicAuthFilter;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import javax.security.auth.Subject;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.message.AuthException;
import javax.security.auth.message.AuthStatus;
import javax.security.auth.message.MessageInfo;
import javax.security.auth.message.MessagePolicy;
import javax.security.auth.message.callback.CallerPrincipalCallback;
import javax.security.auth.message.module.ServerAuthModule;
import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.glassfish.admingui.common.util.RestResponse;
import org.jvnet.hk2.component.Habitat;
import com.sun.enterprise.config.serverbeans.Domain;
import com.sun.enterprise.security.SecurityServicesUtil;
import org.glassfish.admingui.common.util.RestUtil;

/**
 *  <p>	This class is responsible for providing the Authentication support
 *	needed by the admin console to both access the admin console pages
 *	as well as invoke REST requests.</p>
 */
public class AdminConsoleAuthModule implements ServerAuthModule {
    public static final String TOKEN_ADMIN_LISTENER_PORT = "${ADMIN_LISTENER_PORT}";
    private CallbackHandler handler = null;
    private String restURL = null;
    private String loginPage = null;
    private String loginErrorPage = null;
    private static final Class [] SUPPORTED_MESSAGE_TYPES = new Class[] { HttpServletRequest.class, HttpServletResponse.class };
    private static final String SAVED_SUBJECT = "Saved_Subject";
    private static final String USER_NAME = "userName";
    private static final String RESPONSE_TYPE = "application/json";

    /**
     *	The Session key for the REST Server Name.
     */
    public static final String REST_SERVER_NAME = "serverName";

    /**
     *	The Session key for the REST Server Port.
     */
    public static final String REST_SERVER_PORT = "serverPort";

    /**
     *	The Session key for the REST authentication token.
     */
    public static final String REST_TOKEN = "__rTkn__";
    

    /**
     *	<p> This method configures this AuthModule and makes sure all the
     *	    information needed to continue is present.</p>
     */
    public void initialize(MessagePolicy requestPolicy, MessagePolicy responsePolicy, CallbackHandler handler, Map options) throws AuthException {
	this.handler = handler;
	if (options != null) {
	    // Save the REST URL we need to authenticate the user.
	    this.restURL = (String) options.get("restAuthURL");
	    if (restURL == null) {
		throw new AuthException("'restAuthURL' "
		    + "must be supplied as a property in the provider-config "
		    + "in the domain.xml file!");
	    }
	    this.loginPage = (String) options.get("loginPage"); 
	    if (loginPage == null) {
		throw new AuthException("'loginPage' "
		    + "must be supplied as a property in the provider-config "
		    + "in the domain.xml file!");
	    }
	    this.loginErrorPage = (String) options.get("loginErrorPage"); 
	    if (loginErrorPage == null) {
		throw new AuthException("'loginErrorPage' "
		    + "must be supplied as a property in the provider-config "
		    + "in the domain.xml file!");
	    }
            if (restURL.contains(TOKEN_ADMIN_LISTENER_PORT)) {
                Habitat habitat = SecurityServicesUtil.getInstance().getHabitat();
                Domain domain = habitat.getComponent(Domain.class);
                String port = domain.getServerNamed("server").getConfig().getNetworkConfig().getNetworkListener("admin-listener").getPort();
                restURL = restURL.replace(TOKEN_ADMIN_LISTENER_PORT, port);
            }
	}
    }

    /**
     *
     */
    public Class[] getSupportedMessageTypes() {
	return SUPPORTED_MESSAGE_TYPES;
    }

    /**
     *	<p> This is where the validation happens...</p>
     */
    public AuthStatus validateRequest(MessageInfo messageInfo, Subject clientSubject, Subject serviceSubject) throws AuthException {
	// Make sure we need to check...
	HttpServletRequest request =
	    (HttpServletRequest) messageInfo.getRequestMessage();
	HttpServletResponse response =
	    (HttpServletResponse) messageInfo.getResponseMessage();
	if (!isMandatory(messageInfo) &&
		!request.getRequestURI().endsWith("/j_security_check")) {
	    return AuthStatus.SUCCESS;
	}

	// See if we've already checked...
	HttpSession session = request.getSession(true);
	if (session != null) {
	    Subject savedClientSubject = (Subject) session.getValue(SAVED_SUBJECT);
	    if (savedClientSubject != null) {
		// Copy all principals...
		clientSubject.getPrincipals().addAll(
			savedClientSubject.getPrincipals());
		clientSubject.getPublicCredentials().addAll(savedClientSubject.getPublicCredentials());
		clientSubject.getPrivateCredentials().addAll(savedClientSubject.getPrivateCredentials());
		return AuthStatus.SUCCESS;
	    }
	}

	// See if we've already calculated the serverName / serverPort
	if (session.getValue(REST_SERVER_NAME) == null) {
	    // Save this for use later...
	    URL url = null;
	    try {
		url = new URL(restURL);
	    } catch (MalformedURLException ex) {
		throw new IllegalArgumentException(
			"Unable to parse REST URL: (" + restURL + ")", ex);
	    }
	    session.putValue(REST_SERVER_NAME, url.getHost());
	    session.putValue(REST_SERVER_PORT, url.getPort());
	}

	// See if the username / password has been passed in...
	String username = request.getParameter("j_username");
	String password = request.getParameter("j_password");
	if ((username == null) || (password == null) || !request.getMethod().equalsIgnoreCase("post")) {
	    // Not passed in, show the login page...
	    RequestDispatcher rd = request.getRequestDispatcher(loginPage);
	    try {
		rd.forward(request, response);
	    } catch (Exception ex) {
		AuthException ae = new AuthException();
		ae.initCause(ex);
		throw ae;
	    }
	    return AuthStatus.SEND_CONTINUE;
	}

// Don't use the PasswordValidationCallback... use REST authorization instead.
//	char[] pwd = new char[password.length()];
//	password.getChars(0, password.length(), pwd, 0);
//	PasswordValidationCallback pwdCallback =
//	    new PasswordValidationCallback(clientSubject, username, pwd);

	// Make REST Request

        Client client2 = Client.create();
        System.out.println("================ call RestUtil.initialize()");
        RestUtil.initialize(client2, (String)session.getValue(REST_SERVER_NAME));
	WebResource webResource = client2.resource(restURL);
	webResource.addFilter(new HTTPBasicAuthFilter(username, password));
	ClientResponse resp = webResource.accept(RESPONSE_TYPE).post(ClientResponse.class);
	RestResponse restResp = RestResponse.getRestResponse(resp);

	// Check to see if successful..
	if (restResp.isSuccess()) {
	    // Username and Password sent in... validate them!
	    CallerPrincipalCallback cpCallback =
		new CallerPrincipalCallback(clientSubject, username);
	    try {
		handler.handle(new Callback[] { /*pwdCallback,*/ cpCallback });
	    } catch (Exception ex) {
		AuthException ae = new AuthException();
		ae.initCause(ex);
		throw ae;
	    }

            // recreate the session
            Map<String, Object> map = new HashMap<String, Object>();
            Enumeration<String> names = session.getAttributeNames();
            while (names.hasMoreElements()) {
                String key = names.nextElement();
                map.put(key, session.getAttribute(key));
            }
            session.invalidate();
            session = request.getSession(true);
            for (String key : map.keySet()) {
                session.setAttribute(key, map.get(key));
            }

	    if (session != null) {
		// Get the "extraProperties" section of the response...
		Object obj = restResp.getResponse().get("data");
		Map extraProperties = null;
		if ((obj != null) && (obj instanceof Map)) {
		    obj = ((Map) obj).get("extraProperties");
		    if ((obj != null) && (obj instanceof Map)) {
			extraProperties = (Map) obj;
		    }
		}

		// Save the Rest Token...
		if (extraProperties != null) {
		    session.putValue(REST_TOKEN, extraProperties.get("token"));
		}

		// Save the Subject...
		session.putValue(SAVED_SUBJECT, clientSubject);

		// Save the userName
		session.putValue(USER_NAME, username);
	    }
            System.out.println("================ call RestUtil.initialize() in line# 269");
            RestUtil.initialize(null, (String) session.getValue(REST_SERVER_NAME));
	    try {
		// Redirect...
		response.sendRedirect(response.encodeRedirectURL("/index.jsf"));
	    } catch (Exception ex) {
		AuthException ae = new AuthException();
		ae.initCause(ex);
		throw ae;
	    }

	    // Continue...
	    return AuthStatus.SEND_CONTINUE;
	} else {
	    RequestDispatcher rd = request.getRequestDispatcher(this.loginErrorPage);
	    try {
		rd.forward(request, response);
	    } catch (Exception ex) {
		AuthException ae = new AuthException();
		ae.initCause(ex);
		throw ae;
	    }
	    return AuthStatus.SEND_FAILURE;
	}
    }

    /**
     *
     */
    public AuthStatus secureResponse(MessageInfo messageInfo, Subject serviceSubject) throws AuthException {
	return AuthStatus.SUCCESS;
    }

    /**
     *
     */
    public void cleanSubject(MessageInfo messageInfo, Subject subject) throws AuthException {
	// FIXME: Cleanup...
    }

    /**
     *
     */
    private boolean isMandatory(MessageInfo messageInfo) {
	return Boolean.valueOf((String)messageInfo.getMap().get(
	    "javax.security.auth.message.MessagePolicy.isMandatory"));
    }
}