/**
* 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.wss4j.dom.validate;
import java.security.Key;
import java.security.Principal;
import java.security.PrivilegedActionException;
import java.util.Set;
import javax.security.auth.Subject;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.login.LoginContext;
import javax.security.auth.login.LoginException;
import org.apache.wss4j.common.ext.WSSecurityException;
import org.apache.wss4j.common.ext.WSSecurityException.ErrorCode;
import org.apache.wss4j.common.kerberos.KerberosServiceContext;
import org.apache.wss4j.common.kerberos.KerberosServiceExceptionAction;
import org.apache.wss4j.common.kerberos.KerberosTokenDecoder;
import org.apache.wss4j.common.kerberos.KerberosTokenDecoderException;
import org.apache.wss4j.common.kerberos.KerberosTokenDecoderImpl;
import org.apache.wss4j.dom.handler.RequestData;
import org.apache.wss4j.dom.message.token.BinarySecurity;
import org.apache.wss4j.dom.message.token.KerberosSecurity;
/**
*/
public class KerberosTokenValidator implements Validator {
private static final org.slf4j.Logger LOG =
org.slf4j.LoggerFactory.getLogger(KerberosTokenValidator.class);
private String serviceName;
private CallbackHandler callbackHandler;
private String contextName;
private KerberosTokenDecoder kerberosTokenDecoder;
private boolean isUsernameServiceNameForm;
/**
* Get the JAAS Login context name to use.
* @return the JAAS Login context name to use
*/
public String getContextName() {
return contextName;
}
/**
* Set the JAAS Login context name to use.
* @param contextName the JAAS Login context name to use
*/
public void setContextName(String contextName) {
this.contextName = contextName;
}
/**
* Get the CallbackHandler to use with the LoginContext
* @return the CallbackHandler to use with the LoginContext
*/
public CallbackHandler getCallbackHandler() {
return callbackHandler;
}
/**
* Set the CallbackHandler to use with the LoginContext. It can be null.
* @param callbackHandler the CallbackHandler to use with the LoginContext
*/
public void setCallbackHandler(CallbackHandler callbackHandler) {
this.callbackHandler = callbackHandler;
}
/**
* The name of the service to use when contacting the KDC. This value can be null, in which
* case it defaults to the current principal name.
* @param serviceName the name of the service to use when contacting the KDC
*/
public void setServiceName(String serviceName) {
this.serviceName = serviceName;
}
/**
* Get the name of the service to use when contacting the KDC. This value can be null, in which
* case it defaults to the current principal name.
* @return the name of the service to use when contacting the KDC
*/
public String getServiceName() {
return serviceName;
}
/**
* Get the KerberosTokenDecoder instance used to extract a session key from the received Kerberos
* token.
* @return the KerberosTokenDecoder instance used to extract a session key
*/
public KerberosTokenDecoder getKerberosTokenDecoder() {
return kerberosTokenDecoder;
}
/**
* Set the KerberosTokenDecoder instance used to extract a session key from the received Kerberos
* token.
* @param kerberosTokenDecoder the KerberosTokenDecoder instance used to extract a session key
*/
public void setKerberosTokenDecoder(KerberosTokenDecoder kerberosTokenDecoder) {
this.kerberosTokenDecoder = kerberosTokenDecoder;
}
/**
* Validate the credential argument. It must contain a non-null BinarySecurityToken.
*
* @param credential the Credential to be validated
* @param data the RequestData associated with the request
* @throws WSSecurityException on a failed validation
*/
public Credential validate(Credential credential, RequestData data) throws WSSecurityException {
if (credential == null || credential.getBinarySecurityToken() == null) {
throw new WSSecurityException(WSSecurityException.ErrorCode.FAILURE, "noCredential");
}
BinarySecurity binarySecurity = credential.getBinarySecurityToken();
if (!(binarySecurity instanceof KerberosSecurity)) {
return credential;
}
if (LOG.isDebugEnabled()) {
try {
String jaasAuth = System.getProperty("java.security.auth.login.config");
String krbConf = System.getProperty("java.security.krb5.conf");
LOG.debug("KerberosTokenValidator - Using JAAS auth login file: " + jaasAuth);
LOG.debug("KerberosTokenValidator - Using KRB conf file: " + krbConf);
} catch (SecurityException ex) {
LOG.debug(ex.getMessage(), ex);
}
}
// Get a TGT from the KDC using JAAS
LoginContext loginContext = null;
try {
if (callbackHandler != null) {
loginContext = new LoginContext(getContextName(), callbackHandler);
} else if (data.getCallbackHandler() != null) {
loginContext = new LoginContext(getContextName(), data.getCallbackHandler());
} else {
loginContext = new LoginContext(getContextName());
}
loginContext.login();
} catch (LoginException ex) {
if (LOG.isDebugEnabled()) {
LOG.debug(ex.getMessage(), ex);
}
throw new WSSecurityException(
WSSecurityException.ErrorCode.FAILURE,
"kerberosLoginError",
ex,
ex.getMessage()
);
}
if (LOG.isDebugEnabled()) {
LOG.debug("Successfully authenticated to the TGT");
}
byte[] token = binarySecurity.getToken();
// Get the service name to use - fall back on the principal
Subject subject = loginContext.getSubject();
String service = serviceName;
if (service == null) {
Set<Principal> principals = subject.getPrincipals();
if (principals.isEmpty()) {
throw new WSSecurityException(
WSSecurityException.ErrorCode.FAILURE,
"kerberosLoginError",
"No Client principals found after login");
}
service = principals.iterator().next().getName();
}
// Validate the ticket
KerberosServiceExceptionAction action = new KerberosServiceExceptionAction(token, service, isUsernameServiceNameForm());
KerberosServiceContext krbServiceCtx = null;
try {
krbServiceCtx = Subject.doAs(subject, action);
} catch (PrivilegedActionException e) {
Throwable cause = e.getCause();
if (cause instanceof WSSecurityException) {
throw (WSSecurityException) cause;
} else {
throw new WSSecurityException(
ErrorCode.FAILURE, "kerberosTicketValidationError", new Object[] {}, cause
);
}
}
credential.setPrincipal(krbServiceCtx.getPrincipal());
credential.setDelegationCredential(krbServiceCtx.getDelegationCredential());
// Check to see if the session key is available in KerberosServiceContext
LOG.debug("Trying to obtain the Session Key from the KerberosServiceContext.");
Key sessionKey = krbServiceCtx.getSessionKey();
if (null != sessionKey) {
LOG.debug("Found session key in the KerberosServiceContext.");
credential.setSecretKey(sessionKey.getEncoded());
} else {
LOG.debug("Session key is not found in the KerberosServiceContext.");
}
// Otherwise, try to extract the session key from the token if a KerberosTokenDecoder implementation is
// available
if (null == credential.getSecretKey()) {
KerberosTokenDecoder kerberosTokenDecoder = this.kerberosTokenDecoder;
if (kerberosTokenDecoder == null) {
kerberosTokenDecoder = new KerberosTokenDecoderImpl();
}
LOG.debug("KerberosTokenDecoder is set.Trying to obtain the session key from it.");
kerberosTokenDecoder.clear();
kerberosTokenDecoder.setToken(token);
kerberosTokenDecoder.setSubject(subject);
try {
byte[] key = kerberosTokenDecoder.getSessionKey();
if (null != key) {
LOG.debug("Session key obtained from the KerberosTokenDecoder.");
credential.setSecretKey(key);
} else {
LOG.debug("Session key could not be obtained from the KerberosTokenDecoder.");
}
} catch (KerberosTokenDecoderException e) {
// TODO
throw new WSSecurityException(ErrorCode.FAILURE, "Error retrieving session key.", e);
}
} else {
LOG.debug("KerberosTokenDecoder is not set.");
}
if (LOG.isDebugEnabled()) {
LOG.debug("Successfully validated a ticket");
}
return credential;
}
/**
* SPN can be configured to be in either <b>"hostbased"</b> or <b>"username"</b> form.<br/>
* - <b>"hostbased"</b> - specifies that the service principal name should be interpreted as a "host-based" name as specified in GSS API Rfc, section "4.1: Host-Based Service Name Form" - The service name, as it is specified in LDAP/AD, as it is listed in the KDC.<br/>
* - <b>"username"</b> - specifies that the service principal name should be interpreted as a "username" name as specified in GSS API Rfc, section "4.2: User Name Form" � This is usually the client username in LDAP/AD used for authentication to the KDC.
*
* <br/><br/>Default is <b>"hostbased"</b>.
*
* @return the isUsernameServiceNameForm
*/
public boolean isUsernameServiceNameForm() {
return isUsernameServiceNameForm;
}
/**
* If true - sets the SPN form to "username"
* <br/>If false<b>(default)</b> - the SPN form is "hostbased"
*
* @see KerberosSecurity#retrieveServiceTicket(String, CallbackHandler, String, boolean)
*
* @param isUsernameServiceNameForm the isUsernameServiceNameForm to set
*/
public void setUsernameServiceNameForm(boolean isUsernameServiceNameForm) {
this.isUsernameServiceNameForm = isUsernameServiceNameForm;
}
}