8048073: Cannot read ccache entry with a realm-less service name

Reviewed-by: xuelei

jdk/src/share/classes/sun/security/krb5/internal/ccache/CCacheInputStream.java

@@ -334,15 +334,29 @@ public class CCacheInputStream extends KrbDataInputStream implements FileCCacheC
      * returns null.
      */
     Credentials readCred(int version) throws IOException,RealmException, KrbApErrException, Asn1Exception {
-        PrincipalName cpname = readPrincipal(version);
-        if (DEBUG)
+        PrincipalName cpname = null;
+        try {
+            cpname = readPrincipal(version);
+        } catch (Exception e) {
+            // Do not return here. All data for this cred should be fully
+            // consumed so that we can read the next one.
+        }
+        if (DEBUG) {
             System.out.println(">>>DEBUG <CCacheInputStream>  client principal is " + cpname);
-        PrincipalName spname = readPrincipal(version);
-        if (DEBUG)
+        }
+        PrincipalName spname = null;
+        try {
+            spname = readPrincipal(version);
+        } catch (Exception e) {
+            // same as above
+        }
+        if (DEBUG) {
             System.out.println(">>>DEBUG <CCacheInputStream> server principal is " + spname);
+        }
         EncryptionKey key = readKey(version);
-        if (DEBUG)
+        if (DEBUG) {
             System.out.println(">>>DEBUG <CCacheInputStream> key type: " + key.getEType());
+        }
         long times[] = readTimes();
         KerberosTime authtime = new KerberosTime(times[0]);
         KerberosTime starttime =
@@ -375,6 +389,11 @@ public class CCacheInputStream extends KrbDataInputStream implements FileCCacheC
         byte[] ticketData = readData();
         byte[] ticketData2 = readData();
 
+        // Skip this cred if either cpname or spname isn't created.
+        if (cpname == null || spname == null) {
+            return null;
+        }
+
         try {
             return new Credentials(cpname, spname, key, authtime, starttime,
                 endtime, renewTill, skey, tFlags,

jdk/test/sun/security/krb5/ccache/EmptyRealmCC.java

@@ -0,0 +1,68 @@
+/*
+ * 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 8048073
+ * @summary Cannot read ccache entry with a realm-less service name
+ * @compile -XDignore.symbol.file EmptyRealmCC.java
+ * @run main EmptyRealmCC
+ */
+import java.nio.file.Files;
+import java.nio.file.Paths;
+
+import sun.security.krb5.internal.ccache.CredentialsCache;
+
+public class EmptyRealmCC {
+    public static void main(String[] args) throws Exception {
+        byte[] ccache = TimeInCCache.ccache;
+
+        // The service name starts at 0x52:
+        //
+        //    0050:    00 00 00 02 00 00 00 0A 4D 41 58 49 2E 4C
+        //             ----------- -----------
+        //    0060: 4F 43 41 4C 00 00 00 06 6B 72 62 74 67 74 00 00
+        //                      -----------                   -----
+        //    0070: 00 0A 4D 41 58 49 2E 4C 4F 43 41 4C
+        //          -----
+        //
+        // which contains 2 (the length of names), a 10-byte realm, a 6-byte
+        // name[0], and a 10-byte name[1].
+
+        // We will empty the realm, and pack the realm string to another
+        // name (6-byte ".LOCAL"). Finally "krbtgt/MAXI.LOCAL@MAXI.LOCAL"
+        // becomes ".LOCAL/krbtgt/MAXI.LOCAL@".
+
+        // length of names is now 3
+        ccache[0x55] = 3;
+        // The empty realm
+        System.arraycopy(new byte[4], 0, ccache, 0x56, 4);
+        // Length of inserted name is 6
+        System.arraycopy(new byte[]{0,0,0,6}, 0, ccache, 0x5A, 4);
+
+        Files.write(Paths.get("tmpcc"), TimeInCCache.ccache);
+        if (CredentialsCache.getInstance("tmpcc").getCredsList() != null) {
+            throw new Exception("Nothing should be there");
+        }
+    }
+}

jdk/test/sun/security/krb5/ccache/TimeInCCache.java

@@ -28,16 +28,14 @@
  */
 
 import java.io.ByteArrayInputStream;
-import java.lang.reflect.Field;
 import java.lang.reflect.Method;
-import java.nio.file.Files;
-import java.nio.file.Paths;
 
 import sun.security.krb5.internal.ccache.CCacheInputStream;
 import sun.security.krb5.internal.ccache.Credentials;
 
 public class TimeInCCache {
-    // Attention: this field is also used by CorruptedCC.java test
+    // Attention: this field is also used by 2 other tests:
+    // CorruptedCC.java and EmptyRealmCC.java
     public static byte[] ccache;
 
     static {