/*
* 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.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;
import sun.security.krb5.internal.*;
import sun.security.krb5.internal.crypto.KeyUsage;
import sun.security.util.DerInputStream;
abstract class KrbKdcRep {
static void check(
boolean isAsReq,
KDCReq req,
KDCRep rep,
EncryptionKey replyKey
) throws KrbApErrException {
// cname change in AS-REP is allowed only if the client
// sent CANONICALIZE or an NT-ENTERPRISE cname in the request, and the
// server supports RFC 6806 - Section 11 FAST scheme (ENC-PA-REP flag).
if (isAsReq && !req.reqBody.cname.equals(rep.cname) &&
((!req.reqBody.kdcOptions.get(KDCOptions.CANONICALIZE) &&
req.reqBody.cname.getNameType() !=
PrincipalName.KRB_NT_ENTERPRISE) ||
!rep.encKDCRepPart.flags.get(Krb5.TKT_OPTS_ENC_PA_REP))) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
// sname change in TGS-REP is allowed only if client
// sent CANONICALIZE and new sname is a referral of
// the form krbtgt/TO-REALM.COM@FROM-REALM.COM.
if (!req.reqBody.sname.equals(rep.encKDCRepPart.sname)) {
String[] snameStrings = rep.encKDCRepPart.sname.getNameStrings();
if (isAsReq || !req.reqBody.kdcOptions.get(KDCOptions.CANONICALIZE) ||
snameStrings == null || snameStrings.length != 2 ||
!snameStrings[0].equals(PrincipalName.TGS_DEFAULT_SRV_NAME) ||
!rep.encKDCRepPart.sname.getRealmString().equals(
req.reqBody.sname.getRealmString())) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
}
if (req.reqBody.getNonce() != rep.encKDCRepPart.nonce) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
if (
((req.reqBody.addresses != null && rep.encKDCRepPart.caddr != null) &&
!req.reqBody.addresses.equals(rep.encKDCRepPart.caddr))) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
// We allow KDC to return a non-forwardable ticket if request has -f
for (int i = 2; i < 6; i++) {
if (req.reqBody.kdcOptions.get(i) !=
rep.encKDCRepPart.flags.get(i)) {
if (Krb5.DEBUG) {
System.out.println("> KrbKdcRep.check: at #" + i
+ ". request for " + req.reqBody.kdcOptions.get(i)
+ ", received " + rep.encKDCRepPart.flags.get(i));
}
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
}
// Reply to a renewable request should be renewable, but if request does
// not contain renewable, KDC is free to issue a renewable ticket (for
// example, if ticket_lifetime is too big).
if (req.reqBody.kdcOptions.get(KDCOptions.RENEWABLE) &&
!rep.encKDCRepPart.flags.get(KDCOptions.RENEWABLE)) {
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
if ((req.reqBody.from == null) || req.reqBody.from.isZero()) {
// verify this is allowed
if ((rep.encKDCRepPart.starttime != null) &&
!rep.encKDCRepPart.starttime.inClockSkew()) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_SKEW);
}
}
if ((req.reqBody.from != null) && !req.reqBody.from.isZero()) {
// verify this is allowed
if ((rep.encKDCRepPart.starttime != null) &&
!req.reqBody.from.equals(rep.encKDCRepPart.starttime)) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
}
if (!req.reqBody.till.isZero() &&
rep.encKDCRepPart.endtime.greaterThan(req.reqBody.till)) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
// RFC 6806 - Section 11 mechanism check
// The availability of the ENC-PA-REP flag in the KDC response is
// mandatory on some cases (see Krb5.TKT_OPTS_ENC_PA_REP check above).
if (rep.encKDCRepPart.flags.get(Krb5.TKT_OPTS_ENC_PA_REP)) {
boolean reqPaReqEncPaRep = false;
boolean repPaReqEncPaRepValid = false;
if (req.pAData != null) {
for (PAData pa : req.pAData) {
if (pa.getType() == Krb5.PA_REQ_ENC_PA_REP) {
// The KDC supports RFC 6806 and ENC-PA-REP was sent in
// the request (AS-REQ). A valid checksum is now required.
reqPaReqEncPaRep = true;
break;
}
}
}
if (rep.encKDCRepPart.pAData != null) {
for (PAData pa : rep.encKDCRepPart.pAData) {
if (pa.getType() == Krb5.PA_REQ_ENC_PA_REP) {
try {
Checksum repCksum = new Checksum(
new DerInputStream(
pa.getValue()).getDerValue());
// The checksum is inside encKDCRepPart so we don't
// care if it's keyed or not.
repPaReqEncPaRepValid =
repCksum.verifyAnyChecksum(
req.asn1Encode(), replyKey,
KeyUsage.KU_AS_REQ);
} catch (Exception e) {
if (Krb5.DEBUG) {
e.printStackTrace();
}
}
break;
}
}
}
if (reqPaReqEncPaRep && !repPaReqEncPaRepValid) {
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
}
if (req.reqBody.kdcOptions.get(KDCOptions.RENEWABLE)) {
if (req.reqBody.rtime != null && !req.reqBody.rtime.isZero()) {
// verify this is required
if ((rep.encKDCRepPart.renewTill == null) ||
rep.encKDCRepPart.renewTill.greaterThan(req.reqBody.rtime)
) {
rep.encKDCRepPart.key.destroy();
throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
}
}
}
}
}