/*
* Portions Copyright 2001-2004 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
/*
*
* (C) Copyright IBM Corp. 1999 All Rights Reserved.
* Copyright 1997 The Open Group Research Institute. All rights reserved.
*/
package sun.security.krb5.internal;
import sun.security.krb5.*;
import sun.security.krb5.internal.ccache.CredentialsCache;
import java.util.StringTokenizer;
import sun.security.krb5.internal.ktab.*;
import java.io.File;
import java.io.IOException;
import java.util.Date;
import java.util.Vector;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.InetAddress;
/**
* This class is a utility that contains much of the TGS-Exchange
* protocol. It is used by ../Credentials.java for service ticket
* acquisition in both the normal and the x-realm case.
*/
public class CredentialsUtil {
private static boolean DEBUG = sun.security.krb5.internal.Krb5.DEBUG;
/**
* Acquires credentials for a specified service using initial credential. Wh
en the service has a different realm
* from the initial credential, we do cross-realm authentication - first, we
use the current credential to get
* a cross-realm credential from the local KDC, then use that cross-realm cr
edential to request service credential
* from the foreigh KDC.
*
* @param service the name of service principal using format components@real
m
* @param ccreds client's initial credential.
* @exception Exception general exception will be thrown when any error occu
rs.
* @return a <code>Credentials</code> object.
*/
public static Credentials acquireServiceCreds(
String service, Credentials ccreds)
throws KrbException, IOException {
ServiceName sname = new ServiceName(service);
String serviceRealm = sname.getRealmString();
String localRealm = ccreds.getClient().getRealmString();
String defaultRealm = Config.getInstance().getDefaultRealm();
if (localRealm == null) {
PrincipalName temp = null;
if ((temp = ccreds.getServer()) != null)
localRealm = temp.getRealmString();
}
if (localRealm == null) {
localRealm = defaultRealm;
}
if (serviceRealm == null) {
serviceRealm = localRealm;
sname.setRealm(serviceRealm);
}
/*
if (!localRealm.equalsIgnoreCase(serviceRealm)) { //do cross-realm auth entication
if (DEBUG) {
System.out.println(">>>DEBUG: Credentails request cross realm ticket for " + "krbtgt/" + serviceRealm + "@" + localRealm);
}
Credentials crossCreds = serviceCreds(new ServiceName("krbtgt/" + serviceRealm + "@" + localRealm), ccreds);
if (DEBUG) {
printDebug(crossCreds);
}
Credentials result = serviceCreds(sname, crossCreds);
if (DEBUG) {
printDebug(result);
}
return result;
}
else return serviceCreds(sname, ccreds);
*/
if (localRealm.equals(serviceRealm))
{
if (DEBUG)
System.out.println(">>> Credentials acquireServiceCreds: same realm");
return serviceCreds(sname, ccreds);
}
// Get a list of realms to traverse
String[] realms = Realm.getRealmsList(localRealm, serviceRealm);
if (realms == null || realms.length == 0)
{
if (DEBUG)
System.out.println(">>> Credentials acquireServiceCreds: no realms list");
return null;
}
int i = 0, k = 0;
Credentials cTgt = null, newTgt = null, theTgt = null;
ServiceName tempService = null;
String realm = null, newTgtRealm = null, theTgtRealm = null;
for (cTgt = ccreds, i = 0; i < realms.length;)
{
tempService = new ServiceName(PrincipalName.TGS_DEFAULT_SRV_NAME,
serviceRealm, realms[i]);
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: main loop: [" + i +"] tempService=" + tempService);
}
try {
newTgt = serviceCreds(tempService, cTgt);
} catch (Exception exc) {
newTgt = null;
}
if (newTgt == null)
{
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: no tgt; searching backwards");
}
/*
* No tgt found. Try to get one for a
* realm as close to the target as possible.
* That means traversing the realms list backwards.
*/
for (newTgt = null, k = realms.length - 1;
newTgt == null && k > i; k--)
{
tempService = new ServiceName(
PrincipalName.TGS_DEFAULT_SRV_NAME,
realms[k], realms[i]);
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: inner loop: [" + k +"] tempService=" + tempService);
}
try {
newTgt = serviceCreds(tempService, cTgt);
} catch (Exception exc) {
newTgt = null;
}
}
} // Ends 'if (newTgt == null)'
if (newTgt == null)
{
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: no tgt; cannot get creds");
}
break;
}
/*
* We have a tgt. It may or may not be for the target.
* If it's for the target realm, we're done looking for a tgt.
*/
newTgtRealm = newTgt.getServer().getInstanceComponent();
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: got tgt");
//printDebug(newTgt);
}
if (newTgtRealm.equals(serviceRealm))
{
/* We got the right tgt */
theTgt = newTgt;
theTgtRealm = newTgtRealm;
break;
}
/*
* The new tgt is not for the target realm.
* See if the realm of the new tgt is in the list of realms
* and continue looking from there.
*/
for (k = i+1; k < realms.length; k++)
{
if (newTgtRealm.equals(realms[k]))
{
break;
}
}
if (k < realms.length)
{
/*
* (re)set the counter so we start looking
* from the realm we just obtained a tgt for.
*/
i = k;
cTgt = newTgt;
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: continuing with main loop counter reset to " + i);
}
continue;
}
else
{
/*
* The new tgt's realm is not in the heirarchy of realms.
* It's probably not safe to get a tgt from
* a tgs that is outside the known list of realms.
* Give up now.
*/
break;
}
} // Ends outermost/main 'for' loop
Credentials theCreds = null;
if (theTgt != null)
{
/* We have the right tgt. Let's get the service creds */
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: got right tgt");
//printDebug(theTgt);
System.out.println(">>> Credentials acquireServiceCreds: obtaining service creds for " + sname);
}
try {
theCreds = serviceCreds(sname, theTgt);
} catch (Exception exc) {
if (DEBUG)
System.out.println(exc);
theCreds = null;
}
}
if (theCreds != null)
{
if (DEBUG)
{
System.out.println(">>> Credentials acquireServiceCreds: returning creds:");
Credentials.printDebug(theCreds);
}
return theCreds;
}
throw new KrbApErrException(Krb5.KRB_AP_ERR_GEN_CRED,
"No service creds");
}
/*
* This method does the real job to request the service credential.
*/
private static Credentials serviceCreds(
ServiceName service, Credentials ccreds)
throws KrbException, IOException {
return new KrbTgsReq(ccreds, service).sendAndGetCreds();
}
}