svn merge -c 1176729 from trunk for HDFS-2361.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1189440 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -1082,6 +1082,8 @@ Release 0.23.0 - Unreleased
     HDFS-2366. Initialize WebHdfsFileSystem.ugi in object construction.
     (szetszwo)
 
+    HDFS-2361. hftp is broken, fixed username checks in JspHelper. (jitendra)
+
   BREAKDOWN OF HDFS-1073 SUBTASKS
 
     HDFS-1521. Persist transaction ID on disk between NN restarts.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/JspHelper.java

@@ -60,6 +60,7 @@ import org.apache.hadoop.http.HtmlQuoting;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.AccessControlException;
+import org.apache.hadoop.security.authentication.util.KerberosName;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.UserGroupInformation.AuthenticationMethod;
 import org.apache.hadoop.security.token.Token;
@@ -552,7 +553,8 @@ public class JspHelper {
         DelegationTokenIdentifier id = new DelegationTokenIdentifier();
         id.readFields(in);
         ugi = id.getUser();
-        checkUsername(ugi.getUserName(), user);
+        checkUsername(ugi.getShortUserName(), usernameFromQuery);
+        checkUsername(ugi.getShortUserName(), user);
         ugi.addToken(token);
         ugi.setAuthenticationMethod(AuthenticationMethod.TOKEN);
       } else {
@@ -561,13 +563,11 @@ public class JspHelper {
                                 "authenticated by filter");
         }
         ugi = UserGroupInformation.createRemoteUser(user);
+        checkUsername(ugi.getShortUserName(), usernameFromQuery);
         // This is not necessarily true, could have been auth'ed by user-facing
         // filter
         ugi.setAuthenticationMethod(secureAuthMethod);
       }
-
-      checkUsername(user, usernameFromQuery);
-
     } else { // Security's not on, pull from url
       ugi = usernameFromQuery == null?
           getDefaultWebUser(conf) // not specified in request
@@ -580,10 +580,18 @@ public class JspHelper {
     return ugi;
   }
 
+  /**
+   * Expected user name should be a short name.
+   */
   private static void checkUsername(final String expected, final String name
       ) throws IOException {
-    if (name != null && !name.equals(expected)) {
-      throw new IOException("Usernames not matched: name=" + name
+    if (name == null) {
+      return;
+    }
+    KerberosName u = new KerberosName(name);
+    String shortName = u.getShortName();
+    if (!shortName.equals(expected)) {
+      throw new IOException("Usernames not matched: name=" + shortName
           + " != expected=" + expected);
     }
   }