001/**
002 *
003 * Copyright 2014-2015 Florian Schmaus
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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 */
017package org.jivesoftware.smack.sasl.core;
018
019import javax.security.auth.callback.CallbackHandler;
020
021import org.jivesoftware.smack.SmackException;
022import org.jivesoftware.smack.sasl.SASLMechanism;
023import org.jivesoftware.smack.util.stringencoder.Base64;
024
025/**
026 * The SASL X-OAUTH2 mechanism as described in <a
027 * href="https://developers.google.com/talk/jep_extensions/oauth">https://developers.google
028 * .com/talk/jep_extensions/oauth</a>
029 * <p>
030 * The given password will be used as OAUTH token.
031 * </p>
032 * <p>
033 * Note that X-OAUTH2 is experimental in Smack. This is because Google defined, besides being a bad practice (XEP-134),
034 * custom attributes to the 'auth' stanza, as can be seen here
035 * </p>
036 * 
037 * <pre>
038 * {@code
039 * <auth xmlns="urn:ietf:params:xml:ns:xmpp-sasl" mechanism="X-OAUTH2"
040 *    auth:service="chromiumsync" auth:allow-generated-jid="true"
041 *    auth:client-uses-full-bind-result="true" xmlns:auth="http://www.google.com/talk/protocol/auth">
042 * }
043 * </pre>
044 * 
045 * from https://developers.google.com/cloud-print/docs/rawxmpp and here
046 * 
047 * <pre>
048 * {@code
049 * <auth xmlns="urn:ietf:params:xml:ns:xmpp-sasl"
050 *   mechanism="X-OAUTH2"
051 *   auth:service="oauth2"
052 *   xmlns:auth="http://www.google.com/talk/protocol/auth">
053 * base64("\0" + user_name + "\0" + oauth_token)
054 * </auth>
055 * }
056 * </pre>
057 * 
058 * from https://developers.google.com/talk/jep_extensions/oauth
059 * <p>
060 * Those attribute extensions are currently not supported by Smack, and it's unclear how it affects authorization and
061 * how widely they are used.
062 * </p>
063 */
064public class SASLXOauth2Mechanism extends SASLMechanism {
065
066    public static final String NAME = "X-OAUTH2";
067
068    @Override
069    protected void authenticateInternal(CallbackHandler cbh) throws SmackException {
070        throw new UnsupportedOperationException("CallbackHandler not (yet) supported");
071    }
072
073    @Override
074    protected byte[] getAuthenticationText() throws SmackException {
075        // base64("\0" + user_name + "\0" + oauth_token)
076        return Base64.encode(toBytes('\u0000' + authenticationId + '\u0000' + password));
077    }
078
079    @Override
080    public String getName() {
081        return NAME;
082    }
083
084    @Override
085    public int getPriority() {
086        // Same priority as SASL PLAIN
087        return 410;
088    }
089
090    @Override
091    public SASLXOauth2Mechanism newInstance() {
092        return new SASLXOauth2Mechanism();
093    }
094
095    @Override
096    public void checkIfSuccessfulOrThrow() throws SmackException {
097        // No check performed
098    }
099}