8022582: Relax response flags checking in sun.security.krb5.KrbKdcRep.check.

Reviewed-by: mullan

src/share/classes/sun/security/krb5/KrbKdcRep.java

@@ -62,7 +62,8 @@ abstract class KrbKdcRep {
             throw new KrbApErrException(Krb5.KRB_AP_ERR_MODIFIED);
         }
 
-        for (int i = 1; i < 6; i++) {
+        // 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) {

src/share/classes/sun/security/krb5/KrbTgsReq.java

@@ -150,19 +150,11 @@ public class KrbTgsReq {
         ctime = KerberosTime.now();
 
         // check if they are valid arguments. The optional fields
-        // should be  consistent with settings in KDCOptions.
-
-        // TODO: Is this necessary? If the TGT is not FORWARDABLE,
-        // you can still request for a FORWARDABLE ticket, just the
-        // KDC will give you a non-FORWARDABLE one. Even if you
-        // cannot use the ticket expected, it still contains info.
-        // This means there will be problem later. We already have
-        // flags check in KrbTgsRep. Of course, sometimes the KDC
-        // will not issue the ticket at all.
+        // should be consistent with settings in KDCOptions.
 
         if (options.get(KDCOptions.FORWARDABLE) &&
                 (!(asCreds.flags.get(Krb5.TKT_OPTS_FORWARDABLE)))) {
-            throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);
+            options.set(KDCOptions.FORWARDABLE, false);
         }
         if (options.get(KDCOptions.FORWARDED)) {
             if (!(asCreds.flags.get(KDCOptions.FORWARDABLE)))

src/share/classes/sun/security/krb5/internal/CredentialsUtil.java

@@ -58,6 +58,9 @@ public class CredentialsUtil {
             // TODO: we do not support kerberos referral now
             throw new KrbException("Cross realm impersonation not supported");
         }
+        if (!ccreds.isForwardable()) {
+            throw new KrbException("S4U2self needs a FORWARDABLE ticket");
+        }
         KrbTgsReq req = new KrbTgsReq(
                 ccreds,
                 ccreds.getClient(),
@@ -68,6 +71,9 @@ public class CredentialsUtil {
         if (!creds.getClient().equals(client)) {
             throw new KrbException("S4U2self request not honored by KDC");
         }
+        if (!creds.isForwardable()) {
+            throw new KrbException("S4U2self ticket must be FORWARDABLE");
+        }
         return creds;
     }
 

test/sun/security/krb5/auto/Context.java

@@ -23,6 +23,7 @@
 
 import com.sun.security.auth.module.Krb5LoginModule;
 import java.security.Key;
+import java.lang.reflect.InvocationTargetException;
 import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
 import java.util.Arrays;
@@ -581,7 +582,12 @@ public class Context {
             out.name = name + " as " + out.cred.getName().toString();
             return out;
         } catch (PrivilegedActionException pae) {
-            throw pae.getException();
+            Exception e = pae.getException();
+            if (e instanceof InvocationTargetException) {
+                throw (Exception)((InvocationTargetException) e).getTargetException();
+            } else {
+                throw e;
+            }
         }
     }
 

test/sun/security/krb5/auto/ForwardableCheck.java

+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. 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.
+ *
+ * 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.
+ */
+
+/*
+ * @test
+ * @bug 8022582
+ * @summary Relax response flags checking in sun.security.krb5.KrbKdcRep.check.
+ * @compile -XDignore.symbol.file ForwardableCheck.java
+ * @run main/othervm ForwardableCheck
+ */
+
+import org.ietf.jgss.GSSException;
+import sun.security.jgss.GSSUtil;
+
+import java.util.Arrays;
+
+public class ForwardableCheck {
+
+    public static void main(String[] args) throws Exception {
+        OneKDC kdc = new OneKDC(null);
+        kdc.writeJAASConf();
+
+        // USER can impersonate someone else
+        kdc.setOption(KDC.Option.ALLOW_S4U2SELF,
+                Arrays.asList(OneKDC.USER + "@" + OneKDC.REALM));
+        // USER2 is sensitive
+        kdc.setOption(KDC.Option.SENSITIVE_ACCOUNTS,
+                Arrays.asList(OneKDC.USER2 + "@" + OneKDC.REALM));
+
+        Context c;
+
+        // USER2 is sensitive but it's still able to get a normal ticket
+        c = Context.fromUserPass(OneKDC.USER2, OneKDC.PASS2, false);
+
+        // ... and connect to another account
+        c.startAsClient(OneKDC.USER, GSSUtil.GSS_KRB5_MECH_OID);
+        c.x().requestCredDeleg(true);
+        c.x().requestMutualAuth(false);
+
+        c.take(new byte[0]);
+
+        if (!c.x().isEstablished()) {
+            throw new Exception("Context should have been established");
+        }
+
+        // ... but will not be able to delegate itself
+        if (c.x().getCredDelegState()) {
+            throw new Exception("Impossible");
+        }
+
+        // Although USER is allowed to impersonate other people,
+        // it cannot impersonate USER2 coz it's sensitive.
+        c = Context.fromUserPass(OneKDC.USER, OneKDC.PASS, false);
+        try {
+            c.impersonate(OneKDC.USER2);
+            throw new Exception("Should fail");
+        } catch (GSSException e) {
+            e.printStackTrace();
+        }
+    }
+}

test/sun/security/krb5/auto/KDC.java

@@ -194,6 +194,10 @@ public class KDC {
          * Krb5.KDC_ERR_POLICY will be send for S4U2proxy request.
          */
         ALLOW_S4U2PROXY,
+        /**
+         * Sensitive accounts can never be delegated.
+         */
+        SENSITIVE_ACCOUNTS,
     };
 
     static {
@@ -638,7 +642,7 @@ public class KDC {
         try {
             System.out.println(realm + "> " + tgsReq.reqBody.cname +
                     " sends TGS-REQ for " +
-                    service);
+                    service + ", " + tgsReq.reqBody.kdcOptions);
             KDCReqBody body = tgsReq.reqBody;
             int[] eTypes = KDCReqBodyDotEType(body);
             int e2 = eTypes[0];     // etype for outgoing session key
@@ -714,7 +718,13 @@ public class KDC {
             boolean[] bFlags = new boolean[Krb5.TKT_OPTS_MAX+1];
             if (body.kdcOptions.get(KDCOptions.FORWARDABLE)
                     && allowForwardable) {
-                bFlags[Krb5.TKT_OPTS_FORWARDABLE] = true;
+                List<String> sensitives = (List<String>)
+                        options.get(Option.SENSITIVE_ACCOUNTS);
+                if (sensitives != null && sensitives.contains(cname.toString())) {
+                    // Cannot make FORWARDABLE
+                } else {
+                    bFlags[Krb5.TKT_OPTS_FORWARDABLE] = true;
+                }
             }
             if (body.kdcOptions.get(KDCOptions.FORWARDED) ||
                     etp.flags.get(Krb5.TKT_OPTS_FORWARDED)) {
@@ -819,7 +829,8 @@ public class KDC {
                     t,
                     edata);
             System.out.println("     Return " + tgsRep.cname
-                    + " ticket for " + tgsRep.ticket.sname);
+                    + " ticket for " + tgsRep.ticket.sname + ", flags "
+                    + tFlags);
 
             DerOutputStream out = new DerOutputStream();
             out.write(DerValue.createTag(DerValue.TAG_APPLICATION,
@@ -865,7 +876,7 @@ public class KDC {
         try {
             System.out.println(realm + "> " + asReq.reqBody.cname +
                     " sends AS-REQ for " +
-                    service);
+                    service + ", " + asReq.reqBody.kdcOptions);
 
             KDCReqBody body = asReq.reqBody;
 
@@ -908,7 +919,13 @@ public class KDC {
             //body.from
             boolean[] bFlags = new boolean[Krb5.TKT_OPTS_MAX+1];
             if (body.kdcOptions.get(KDCOptions.FORWARDABLE)) {
-                bFlags[Krb5.TKT_OPTS_FORWARDABLE] = true;
+                List<String> sensitives = (List<String>)
+                        options.get(Option.SENSITIVE_ACCOUNTS);
+                if (sensitives != null && sensitives.contains(body.cname.toString())) {
+                    // Cannot make FORWARDABLE
+                } else {
+                    bFlags[Krb5.TKT_OPTS_FORWARDABLE] = true;
+                }
             }
             if (body.kdcOptions.get(KDCOptions.RENEWABLE)) {
                 bFlags[Krb5.TKT_OPTS_RENEWABLE] = true;
@@ -1084,7 +1101,8 @@ public class KDC {
                     edata);
 
             System.out.println("     Return " + asRep.cname
-                    + " ticket for " + asRep.ticket.sname);
+                    + " ticket for " + asRep.ticket.sname + ", flags "
+                    + tFlags);
 
             DerOutputStream out = new DerOutputStream();
             out.write(DerValue.createTag(DerValue.TAG_APPLICATION,