Revert HDFS-3639. JspHelper#getUGI should always verify the token if security is enabled.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1362769 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -83,9 +83,6 @@ Release 1.2.0 - unreleased
 
     HADOOP-8587. HarFileSystem access of harMetaCache isn't threadsafe. (eli)
 
-    HDFS-3639. JspHelper#getUGI should always verify the token if
-    security is enabled. (eli)
-
     HADOOP-7836. TestSaslRPC#testDigestAuthMethodHostBasedToken fails
     with hostname localhost.localdomain. (daryn via eli)
  

src/hdfs/org/apache/hadoop/hdfs/server/namenode/JspHelper.java

@@ -486,9 +486,14 @@ public class JspHelper {
         DataInputStream in = new DataInputStream(buf);
         DelegationTokenIdentifier id = new DelegationTokenIdentifier();
         id.readFields(in);
-        NameNode nn = (NameNode) context.getAttribute("name.node");
-        nn.getNamesystem().getDelegationTokenSecretManager()
-          .verifyToken(id, token.getPassword());
+        if (context != null) {
+          NameNode nn = (NameNode) context.getAttribute("name.node");
+          if (nn != null) {
+            //Verify the token.
+            nn.getNamesystem().getDelegationTokenSecretManager()
+                .verifyToken(id, token.getPassword());
+          }
+        }
         ugi = id.getUser();
         if (ugi.getRealUser() == null) {
           //non-proxy case