1
0
Fork 0
mirror of https://github.com/vanitasvitae/Smack.git synced 2024-12-23 19:18:00 +01:00
Smack/source/org/jivesoftware/smack/sasl/SASLMechanism.java

199 lines
8 KiB
Java

/**
* $RCSfile$
* $Revision: $
* $Date: $
*
* Copyright 2003-2007 Jive Software.
*
* All rights reserved. Licensed 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.jivesoftware.smack.sasl;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.SASLAuthentication;
import org.jivesoftware.smack.util.Base64;
import java.io.IOException;
import java.util.Map;
import java.util.HashMap;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.callback.UnsupportedCallbackException;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.NameCallback;
import javax.security.auth.callback.PasswordCallback;
import javax.security.sasl.RealmCallback;
import javax.security.sasl.RealmChoiceCallback;
import javax.security.sasl.Sasl;
import javax.security.sasl.SaslClient;
import javax.security.sasl.SaslException;
/**
* Base class for SASL mechanisms. Subclasses must implement these methods:
* <ul>
* <li>{@link #getName()} -- returns the common name of the SASL mechanism.</li>
* </ul>
* Subclasses will likely want to implement their own versions of these mthods:
* <li>{@link #authenticate(String, String, String)} -- Initiate authentication stanza using the
* deprecated method.</li>
* <li>{@link #authenticate(String, String, CallbackHandler)} -- Initiate authentication stanza
* using the CallbackHandler method.</li>
* <li>{@link #challengeReceived(String)} -- Handle a challenge from the server.</li>
* </ul>
*
* @author Jay Kline
*/
public abstract class SASLMechanism implements CallbackHandler {
private SASLAuthentication saslAuthentication;
protected SaslClient sc;
protected String authenticationId;
protected String password;
protected String hostname;
public SASLMechanism(SASLAuthentication saslAuthentication) {
this.saslAuthentication = saslAuthentication;
}
/**
* Builds and sends the <tt>auth</tt> stanza to the server. Note that this method of
* authentication is not recommended, since it is very inflexable. Use
* {@link #authenticate(String, String, CallbackHandler)} whenever possible.
*
* @param username the username of the user being authenticated.
* @param host the hostname where the user account resides.
* @param password the password for this account.
* @throws IOException If a network error occurs while authenticating.
* @throws XMPPException If a protocol error occurs or the user is not authenticated.
*/
public void authenticate(String username, String host, String password) throws IOException, XMPPException {
//Since we were not provided with a CallbackHandler, we will use our own with the given
//information
//Set the authenticationID as the username, since they must be the same in this case.
this.authenticationId = username;
this.password = password;
this.hostname = host;
String[] mechanisms = { getName() };
Map<String,String> props = new HashMap<String,String>();
sc = Sasl.createSaslClient(mechanisms, username, "xmpp", host, props, this);
authenticate();
}
/**
* Builds and sends the <tt>auth</tt> stanza to the server. The callback handler will handle
* any additional information, such as the authentication ID or realm, if it is needed.
*
* @param username the username of the user being authenticated.
* @param host the hostname where the user account resides.
* @param cbh the CallbackHandler to obtain user information.
* @throws IOException If a network error occures while authenticating.
* @throws XMPPException If a protocol error occurs or the user is not authenticated.
*/
public void authenticate(String username, String host, CallbackHandler cbh) throws IOException, XMPPException {
String[] mechanisms = { getName() };
Map<String,String> props = new HashMap<String,String>();
sc = Sasl.createSaslClient(mechanisms, username, "xmpp", host, props, cbh);
authenticate();
}
protected void authenticate() throws IOException, XMPPException {
StringBuilder stanza = new StringBuilder();
stanza.append("<auth mechanism=\"").append(getName());
stanza.append("\" xmlns=\"urn:ietf:params:xml:ns:xmpp-sasl\">");
try {
if(sc.hasInitialResponse()) {
byte[] response = sc.evaluateChallenge(new byte[0]);
String authenticationText = Base64.encodeBytes(response,Base64.DONT_BREAK_LINES);
if(authenticationText != null && !authenticationText.equals("")) {
stanza.append(authenticationText);
}
}
} catch (SaslException e) {
throw new XMPPException("SASL authentication failed", e);
}
stanza.append("</auth>");
// Send the authentication to the server
getSASLAuthentication().send(stanza.toString());
}
/**
* The server is challenging the SASL mechanism for the stanza he just sent. Send a
* response to the server's challenge.
*
* @param challenge a base64 encoded string representing the challenge.
* @throws IOException if an exception sending the response occurs.
*/
public void challengeReceived(String challenge) throws IOException {
// Build the challenge response stanza encoding the response text
StringBuilder stanza = new StringBuilder();
byte response[];
if(challenge != null) {
response = sc.evaluateChallenge(Base64.decode(challenge));
} else {
response = sc.evaluateChallenge(null);
}
String authenticationText = Base64.encodeBytes(response,Base64.DONT_BREAK_LINES);
if(authenticationText.equals("")) {
authenticationText = "=";
}
stanza.append("<response xmlns=\"urn:ietf:params:xml:ns:xmpp-sasl\">");
stanza.append(authenticationText);
stanza.append("</response>");
// Send the authentication to the server
getSASLAuthentication().send(stanza.toString());
}
/**
* Returns the common name of the SASL mechanism. E.g.: PLAIN, DIGEST-MD5 or GSSAPI.
*
* @return the common name of the SASL mechanism.
*/
protected abstract String getName();
protected SASLAuthentication getSASLAuthentication() {
return saslAuthentication;
}
/**
*
*/
public void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException {
for (int i = 0; i < callbacks.length; i++) {
if (callbacks[i] instanceof NameCallback) {
NameCallback ncb = (NameCallback)callbacks[i];
ncb.setName(authenticationId);
} else if(callbacks[i] instanceof PasswordCallback) {
PasswordCallback pcb = (PasswordCallback)callbacks[i];
pcb.setPassword(password.toCharArray());
} else if(callbacks[i] instanceof RealmCallback) {
RealmCallback rcb = (RealmCallback)callbacks[i];
rcb.setText(hostname);
} else if(callbacks[i] instanceof RealmChoiceCallback){
//unused
//RealmChoiceCallback rccb = (RealmChoiceCallback)callbacks[i];
} else {
throw new UnsupportedCallbackException(callbacks[i]);
}
}
}
}