HDFS-12895. RBF: Add ACL support for mount table. Contributed by Yiqun Lin.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterAdminServer.java

@@ -17,6 +17,9 @@
  */
 package org.apache.hadoop.hdfs.server.federation.router;
 
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_PERMISSIONS_ENABLED_DEFAULT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_PERMISSIONS_ENABLED_KEY;
+
 import java.io.IOException;
 import java.net.InetSocketAddress;
 
@@ -35,9 +38,12 @@ import org.apache.hadoop.hdfs.server.federation.store.protocol.RemoveMountTableE
 import org.apache.hadoop.hdfs.server.federation.store.protocol.RemoveMountTableEntryResponse;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.UpdateMountTableEntryRequest;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.UpdateMountTableEntryResponse;
+import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.ipc.ProtobufRpcEngine;
 import org.apache.hadoop.ipc.RPC;
 import org.apache.hadoop.ipc.RPC.Server;
+import org.apache.hadoop.security.AccessControlException;
+import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.service.AbstractService;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -65,6 +71,14 @@ public class RouterAdminServer extends AbstractService
   private final Server adminServer;
   private final InetSocketAddress adminAddress;
 
+  /**
+   * Permission related info used for constructing new router permission
+   * checker instance.
+   */
+  private static String routerOwner;
+  private static String superGroup;
+  private static boolean isPermissionEnabled;
+
   public RouterAdminServer(Configuration conf, Router router)
       throws IOException {
     super(RouterAdminServer.class.getName());
@@ -96,6 +110,7 @@ public class RouterAdminServer extends AbstractService
     LOG.info("Admin server binding to {}:{}",
         bindHost, confRpcAddress.getPort());
 
+    initializePermissionSettings(this.conf);
     this.adminServer = new RPC.Builder(this.conf)
         .setProtocol(RouterAdminProtocolPB.class)
         .setInstance(clientNNPbService)
@@ -112,6 +127,22 @@ public class RouterAdminServer extends AbstractService
     router.setAdminServerAddress(this.adminAddress);
   }
 
+  /**
+   * Initialize permission related settings.
+   *
+   * @param routerConf
+   * @throws IOException
+   */
+  private static void initializePermissionSettings(Configuration routerConf)
+      throws IOException {
+    routerOwner = UserGroupInformation.getCurrentUser().getShortUserName();
+    superGroup = routerConf.get(
+        DFSConfigKeys.DFS_PERMISSIONS_SUPERUSERGROUP_KEY,
+        DFSConfigKeys.DFS_PERMISSIONS_SUPERUSERGROUP_DEFAULT);
+    isPermissionEnabled = routerConf.getBoolean(DFS_PERMISSIONS_ENABLED_KEY,
+        DFS_PERMISSIONS_ENABLED_DEFAULT);
+  }
+
   /** Allow access to the client RPC server for testing. */
   @VisibleForTesting
   Server getAdminServer() {
@@ -180,4 +211,44 @@ public class RouterAdminServer extends AbstractService
       GetMountTableEntriesRequest request) throws IOException {
     return getMountTableStore().getMountTableEntries(request);
   }
+
+  /**
+   * Get a new permission checker used for making mount table access
+   * control. This method will be invoked during each RPC call in router
+   * admin server.
+   *
+   * @return Router permission checker
+   * @throws AccessControlException
+   */
+  public static RouterPermissionChecker getPermissionChecker()
+      throws AccessControlException {
+    if (!isPermissionEnabled) {
+      return null;
+    }
+
+    try {
+      return new RouterPermissionChecker(routerOwner, superGroup,
+          NameNode.getRemoteUser());
+    } catch (IOException e) {
+      throw new AccessControlException(e);
+    }
+  }
+
+  /**
+   * Get super user name.
+   *
+   * @return String super user name.
+   */
+  public static String getSuperUser() {
+    return routerOwner;
+  }
+
+  /**
+   * Get super group name.
+   *
+   * @return String super group name.
+   */
+  public static String getSuperGroup(){
+    return superGroup;
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterPermissionChecker.java

@@ -0,0 +1,82 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hdfs.server.federation.router;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.fs.permission.FsAction;
+import org.apache.hadoop.fs.permission.FsPermission;
+import org.apache.hadoop.hdfs.server.federation.store.records.MountTable;
+import org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker;
+import org.apache.hadoop.security.AccessControlException;
+import org.apache.hadoop.security.UserGroupInformation;
+
+/**
+ * Class that helps in checking permissions in Router-based federation.
+ */
+public class RouterPermissionChecker extends FSPermissionChecker {
+  static final Log LOG = LogFactory.getLog(RouterPermissionChecker.class);
+
+  /** Mount table default permission. */
+  public static final short MOUNT_TABLE_PERMISSION_DEFAULT = 00755;
+
+  public RouterPermissionChecker(String routerOwner, String supergroup,
+      UserGroupInformation callerUgi) {
+    super(routerOwner, supergroup, callerUgi, null);
+  }
+
+  /**
+   * Whether a mount table entry can be accessed by the current context.
+   *
+   * @param mountTable
+   *          MountTable being accessed
+   * @param access
+   *          type of action being performed on the cache pool
+   * @throws AccessControlException
+   *           if mount table cannot be accessed
+   */
+  public void checkPermission(MountTable mountTable, FsAction access)
+      throws AccessControlException {
+    if (isSuperUser()) {
+      return;
+    }
+
+    FsPermission mode = mountTable.getMode();
+    if (getUser().equals(mountTable.getOwnerName())
+        && mode.getUserAction().implies(access)) {
+      return;
+    }
+
+    if (isMemberOfGroup(mountTable.getGroupName())
+        && mode.getGroupAction().implies(access)) {
+      return;
+    }
+
+    if (!getUser().equals(mountTable.getOwnerName())
+        && !isMemberOfGroup(mountTable.getGroupName())
+        && mode.getOtherAction().implies(access)) {
+      return;
+    }
+
+    throw new AccessControlException(
+        "Permission denied while accessing mount table "
+            + mountTable.getSourcePath()
+            + ": user " + getUser() + " does not have " + access.toString()
+            + " permissions.");
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/federation/store/impl/MountTableStoreImpl.java

@@ -24,6 +24,9 @@ import java.util.List;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
+import org.apache.hadoop.fs.permission.FsAction;
+import org.apache.hadoop.hdfs.server.federation.router.RouterAdminServer;
+import org.apache.hadoop.hdfs.server.federation.router.RouterPermissionChecker;
 import org.apache.hadoop.hdfs.server.federation.store.MountTableStore;
 import org.apache.hadoop.hdfs.server.federation.store.driver.StateStoreDriver;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.AddMountTableEntryRequest;
@@ -36,6 +39,7 @@ import org.apache.hadoop.hdfs.server.federation.store.protocol.UpdateMountTableE
 import org.apache.hadoop.hdfs.server.federation.store.protocol.UpdateMountTableEntryResponse;
 import org.apache.hadoop.hdfs.server.federation.store.records.MountTable;
 import org.apache.hadoop.hdfs.server.federation.store.records.Query;
+import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.util.Time;
 
 /**
@@ -52,7 +56,15 @@ public class MountTableStoreImpl extends MountTableStore {
   @Override
   public AddMountTableEntryResponse addMountTableEntry(
       AddMountTableEntryRequest request) throws IOException {
-    boolean status = getDriver().put(request.getEntry(), false, true);
+    MountTable mountTable = request.getEntry();
+    if (mountTable != null) {
+      RouterPermissionChecker pc = RouterAdminServer.getPermissionChecker();
+      if (pc != null) {
+        pc.checkPermission(mountTable, FsAction.WRITE);
+      }
+    }
+
+    boolean status = getDriver().put(mountTable, false, true);
     AddMountTableEntryResponse response =
         AddMountTableEntryResponse.newInstance();
     response.setStatus(status);
@@ -62,8 +74,15 @@ public class MountTableStoreImpl extends MountTableStore {
   @Override
   public UpdateMountTableEntryResponse updateMountTableEntry(
       UpdateMountTableEntryRequest request) throws IOException {
-    MountTable entry = request.getEntry();
+    MountTable mountTable = request.getEntry();
-    boolean status = getDriver().put(entry, true, true);
+    if (mountTable != null) {
+      RouterPermissionChecker pc = RouterAdminServer.getPermissionChecker();
+      if (pc != null) {
+        pc.checkPermission(mountTable, FsAction.WRITE);
+      }
+    }
+
+    boolean status = getDriver().put(mountTable, true, true);
     UpdateMountTableEntryResponse response =
         UpdateMountTableEntryResponse.newInstance();
     response.setStatus(status);
@@ -77,8 +96,17 @@ public class MountTableStoreImpl extends MountTableStore {
     final MountTable partial = MountTable.newInstance();
     partial.setSourcePath(srcPath);
     final Query<MountTable> query = new Query<>(partial);
-    int removedRecords = getDriver().remove(getRecordClass(), query);
+    final MountTable deleteEntry = getDriver().get(getRecordClass(), query);
-    boolean status = (removedRecords == 1);
+
+    boolean status = false;
+    if (deleteEntry != null) {
+      RouterPermissionChecker pc = RouterAdminServer.getPermissionChecker();
+      if (pc != null) {
+        pc.checkPermission(deleteEntry, FsAction.WRITE);
+      }
+      status = getDriver().remove(deleteEntry);
+    }
+
     RemoveMountTableEntryResponse response =
         RemoveMountTableEntryResponse.newInstance();
     response.setStatus(status);
@@ -88,12 +116,13 @@ public class MountTableStoreImpl extends MountTableStore {
   @Override
   public GetMountTableEntriesResponse getMountTableEntries(
       GetMountTableEntriesRequest request) throws IOException {
-
+    RouterPermissionChecker pc =
+        RouterAdminServer.getPermissionChecker();
     // Get all values from the cache
     List<MountTable> records = getCachedRecords();
 
     // Sort and filter
-    Collections.sort(records);
+    Collections.sort(records, MountTable.SOURCE_COMPARATOR);
     String reqSrcPath = request.getSrcPath();
     if (reqSrcPath != null && !reqSrcPath.isEmpty()) {
       // Return only entries beneath this path
@@ -103,6 +132,15 @@ public class MountTableStoreImpl extends MountTableStore {
         String srcPath = record.getSourcePath();
         if (!srcPath.startsWith(reqSrcPath)) {
           it.remove();
+        } else if (pc != null) {
+          // do the READ permission check
+          try {
+            pc.checkPermission(record, FsAction.READ);
+          } catch (AccessControlException ignored) {
+            // Remove this mount table entry if it cannot
+            // be accessed by current user.
+            it.remove();
+          }
         }
       }
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/federation/store/records/MountTable.java

@@ -28,9 +28,13 @@ import java.util.TreeMap;
 
 import org.apache.commons.lang.builder.HashCodeBuilder;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.server.federation.resolver.RemoteLocation;
 import org.apache.hadoop.hdfs.server.federation.resolver.order.DestinationOrder;
+import org.apache.hadoop.hdfs.server.federation.router.RouterPermissionChecker;
 import org.apache.hadoop.hdfs.server.federation.store.driver.StateStoreSerializer;
+import org.apache.hadoop.hdfs.server.namenode.NameNode;
+import org.apache.hadoop.security.UserGroupInformation;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -127,6 +131,15 @@ public abstract class MountTable extends BaseRecord {
     // Set the serialized dest string
     record.setDestinations(locations);
 
+    // Set permission fields
+    UserGroupInformation ugi = NameNode.getRemoteUser();
+    record.setOwnerName(ugi.getShortUserName());
+    String group = ugi.getGroups().isEmpty() ? ugi.getShortUserName()
+        : ugi.getPrimaryGroupName();
+    record.setGroupName(group);
+    record.setMode(new FsPermission(
+        RouterPermissionChecker.MOUNT_TABLE_PERMISSION_DEFAULT));
+
     // Validate
     record.validate();
     return record;
@@ -193,6 +206,48 @@ public abstract class MountTable extends BaseRecord {
    */
   public abstract void setDestOrder(DestinationOrder order);
 
+  /**
+   * Get owner name of this mount table entry.
+   *
+   * @return Owner name
+   */
+  public abstract String getOwnerName();
+
+  /**
+   * Set owner name of this mount table entry.
+   *
+   * @param owner Owner name for mount table entry
+   */
+  public abstract void setOwnerName(String owner);
+
+  /**
+   * Get group name of this mount table entry.
+   *
+   * @return Group name
+   */
+  public abstract String getGroupName();
+
+  /**
+   * Set group name of this mount table entry.
+   *
+   * @param group Group name for mount table entry
+   */
+  public abstract void setGroupName(String group);
+
+  /**
+   * Get permission of this mount table entry.
+   *
+   * @return FsPermission permission mode
+   */
+  public abstract FsPermission getMode();
+
+  /**
+   * Set permission for this mount table entry.
+   *
+   * @param mode Permission for mount table entry
+   */
+  public abstract void setMode(FsPermission mode);
+
   /**
    * Get the default location.
    * @return The default location.
@@ -235,6 +290,19 @@ public abstract class MountTable extends BaseRecord {
     if (this.isReadOnly()) {
       sb.append("[RO]");
     }
+
+    if (this.getOwnerName() != null) {
+      sb.append("[owner:").append(this.getOwnerName()).append("]");
+    }
+
+    if (this.getGroupName() != null) {
+      sb.append("[group:").append(this.getGroupName()).append("]");
+    }
+
+    if (this.getMode() != null) {
+      sb.append("[mode:").append(this.getMode()).append("]");
+    }
+
     return sb.toString();
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/federation/store/records/impl/pb/MountTablePBImpl.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.util.LinkedList;
 import java.util.List;
 
+import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.federation.protocol.proto.HdfsServerFederationProtos.MountTableRecordProto;
 import org.apache.hadoop.hdfs.federation.protocol.proto.HdfsServerFederationProtos.MountTableRecordProto.Builder;
 import org.apache.hadoop.hdfs.federation.protocol.proto.HdfsServerFederationProtos.MountTableRecordProto.DestOrder;
@@ -28,6 +29,8 @@ import org.apache.hadoop.hdfs.federation.protocol.proto.HdfsServerFederationProt
 import org.apache.hadoop.hdfs.federation.protocol.proto.HdfsServerFederationProtos.RemoteLocationProto;
 import org.apache.hadoop.hdfs.server.federation.resolver.RemoteLocation;
 import org.apache.hadoop.hdfs.server.federation.resolver.order.DestinationOrder;
+import org.apache.hadoop.hdfs.server.federation.router.RouterAdminServer;
+import org.apache.hadoop.hdfs.server.federation.router.RouterPermissionChecker;
 import org.apache.hadoop.hdfs.server.federation.store.protocol.impl.pb.FederationProtocolPBTranslator;
 import org.apache.hadoop.hdfs.server.federation.store.records.MountTable;
 
@@ -189,6 +192,64 @@ public class MountTablePBImpl extends MountTable implements PBRecord {
     }
   }
 
+  @Override
+  public String getOwnerName() {
+    MountTableRecordProtoOrBuilder proto = this.translator.getProtoOrBuilder();
+    if (!proto.hasOwnerName()) {
+      return RouterAdminServer.getSuperUser();
+    }
+    return proto.getOwnerName();
+  }
+
+  @Override
+  public void setOwnerName(String owner) {
+    Builder builder = this.translator.getBuilder();
+    if (owner == null) {
+      builder.clearOwnerName();
+    } else {
+      builder.setOwnerName(owner);
+    }
+  }
+
+  @Override
+  public String getGroupName() {
+    MountTableRecordProtoOrBuilder proto = this.translator.getProtoOrBuilder();
+    if (!proto.hasGroupName()) {
+      return RouterAdminServer.getSuperGroup();
+    }
+    return proto.getGroupName();
+  }
+
+  @Override
+  public void setGroupName(String group) {
+    Builder builder = this.translator.getBuilder();
+    if (group == null) {
+      builder.clearGroupName();
+    } else {
+      builder.setGroupName(group);
+    }
+  }
+
+  @Override
+  public FsPermission getMode() {
+    MountTableRecordProtoOrBuilder proto = this.translator.getProtoOrBuilder();
+    short mode = RouterPermissionChecker.MOUNT_TABLE_PERMISSION_DEFAULT;
+    if (proto.hasMode()) {
+      mode = (short) proto.getMode();
+    }
+    return new FsPermission(mode);
+  }
+
+  @Override
+  public void setMode(FsPermission mode) {
+    Builder builder = this.translator.getBuilder();
+    if (mode == null) {
+      builder.clearMode();
+    } else {
+      builder.setMode(mode.toShort());
+    }
+  }
+
   private DestinationOrder convert(DestOrder order) {
     switch (order) {
     case LOCAL:

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSPermissionChecker.java

@@ -46,7 +46,7 @@ import org.apache.hadoop.security.UserGroupInformation;
  * 
  * Some of the helper methods are gaurded by {@link FSNamesystem#readLock()}.
  */
-class FSPermissionChecker implements AccessControlEnforcer {
+public class FSPermissionChecker implements AccessControlEnforcer {
   static final Log LOG = LogFactory.getLog(UserGroupInformation.class);
 
   private static String getPath(byte[][] components, int start, int end) {
@@ -86,7 +86,7 @@ class FSPermissionChecker implements AccessControlEnforcer {
   private final INodeAttributeProvider attributeProvider;
 
 
-  FSPermissionChecker(String fsOwner, String supergroup,
+  protected FSPermissionChecker(String fsOwner, String supergroup,
       UserGroupInformation callerUgi,
       INodeAttributeProvider attributeProvider) {
     this.fsOwner = fsOwner;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/federation/RouterAdmin.java

@@ -26,6 +26,7 @@ import java.util.Map;
 import org.apache.hadoop.classification.InterfaceAudience.Private;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.conf.Configured;
+import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.server.federation.resolver.MountTableManager;
@@ -77,7 +78,7 @@ public class RouterAdmin extends Configured implements Tool {
   public void printUsage() {
     String usage = "Federation Admin Tools:\n"
         + "\t[-add <source> <nameservice> <destination> "
-        + "[-readonly]\n"
+        + "[-readonly] -owner <owner> -group <group> -mode <mode>]\n"
         + "\t[-rm <source>]\n"
         + "\t[-ls <path>]\n";
     System.out.println(usage);
@@ -193,6 +194,9 @@ public class RouterAdmin extends Configured implements Tool {
 
     // Optional parameters
     boolean readOnly = false;
+    String owner = null;
+    String group = null;
+    FsPermission mode = null;
     DestinationOrder order = DestinationOrder.HASH;
     while (i < parameters.length) {
       if (parameters[i].equals("-readonly")) {
@@ -204,11 +208,23 @@ public class RouterAdmin extends Configured implements Tool {
         } catch(Exception e) {
           System.err.println("Cannot parse order: " + parameters[i]);
         }
+      } else if (parameters[i].equals("-owner")) {
+        i++;
+        owner = parameters[i];
+      } else if (parameters[i].equals("-group")) {
+        i++;
+        group = parameters[i];
+      } else if (parameters[i].equals("-mode")) {
+        i++;
+        short modeValue = Short.parseShort(parameters[i], 8);
+        mode = new FsPermission(modeValue);
       }
+
       i++;
     }
 
-    return addMount(mount, nss, dest, readOnly, order);
+    return addMount(mount, nss, dest, readOnly, order,
+        new ACLEntity(owner, group, mode));
   }
 
   /**
@@ -219,11 +235,13 @@ public class RouterAdmin extends Configured implements Tool {
    * @param dest Destination path.
    * @param readonly If the mount point is read only.
    * @param order Order of the destination locations.
+   * @param aclInfo the ACL info for mount point.
    * @return If the mount point was added.
    * @throws IOException Error adding the mount point.
    */
   public boolean addMount(String mount, String[] nss, String dest,
-      boolean readonly, DestinationOrder order) throws IOException {
+      boolean readonly, DestinationOrder order, ACLEntity aclInfo)
+      throws IOException {
     // Get the existing entry
     MountTableManager mountTable = client.getMountTableManager();
     GetMountTableEntriesRequest getRequest =
@@ -251,6 +269,20 @@ public class RouterAdmin extends Configured implements Tool {
       if (order != null) {
         newEntry.setDestOrder(order);
       }
+
+      // Set ACL info for mount table entry
+      if (aclInfo.getOwner() != null) {
+        newEntry.setOwnerName(aclInfo.getOwner());
+      }
+
+      if (aclInfo.getGroup() != null) {
+        newEntry.setGroupName(aclInfo.getGroup());
+      }
+
+      if (aclInfo.getMode() != null) {
+        newEntry.setMode(aclInfo.getMode());
+      }
+
       AddMountTableEntryRequest request =
           AddMountTableEntryRequest.newInstance(newEntry);
       AddMountTableEntryResponse addResponse =
@@ -273,6 +305,20 @@ public class RouterAdmin extends Configured implements Tool {
       if (order != null) {
         existingEntry.setDestOrder(order);
       }
+
+      // Update ACL info of mount table entry
+      if (aclInfo.getOwner() != null) {
+        existingEntry.setOwnerName(aclInfo.getOwner());
+      }
+
+      if (aclInfo.getGroup() != null) {
+        existingEntry.setGroupName(aclInfo.getGroup());
+      }
+
+      if (aclInfo.getMode() != null) {
+        existingEntry.setMode(aclInfo.getMode());
+      }
+
       UpdateMountTableEntryRequest updateRequest =
           UpdateMountTableEntryRequest.newInstance(existingEntry);
       UpdateMountTableEntryResponse updateResponse =
@@ -323,8 +369,8 @@ public class RouterAdmin extends Configured implements Tool {
   private static void printMounts(List<MountTable> entries) {
     System.out.println("Mount Table Entries:");
     System.out.println(String.format(
-        "%-25s %-25s",
+        "%-25s %-25s %-25s %-25s %-25s",
-        "Source", "Destinations"));
+        "Source", "Destinations", "Owner", "Group", "Mode"));
     for (MountTable entry : entries) {
       StringBuilder destBuilder = new StringBuilder();
       for (RemoteLocation location : entry.getDestinations()) {
@@ -334,8 +380,38 @@ public class RouterAdmin extends Configured implements Tool {
         destBuilder.append(String.format("%s->%s", location.getNameserviceId(),
             location.getDest()));
       }
-      System.out.println(String.format("%-25s %-25s", entry.getSourcePath(),
+      System.out.print(String.format("%-25s %-25s", entry.getSourcePath(),
           destBuilder.toString()));
+
+      System.out.println(String.format(" %-25s %-25s %-25s",
+          entry.getOwnerName(), entry.getGroupName(), entry.getMode()));
+    }
+  }
+
+  /**
+   * Inner class that stores ACL info of mount table.
+   */
+  static class ACLEntity {
+    private final String owner;
+    private final String group;
+    private final FsPermission mode;
+
+    ACLEntity(String owner, String group, FsPermission mode) {
+      this.owner = owner;
+      this.group = group;
+      this.mode = mode;
+    }
+
+    public String getOwner() {
+      return owner;
+    }
+
+    public String getGroup() {
+      return group;
+    }
+
+    public FsPermission getMode() {
+      return mode;
     }
   }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/proto/FederationProtocol.proto

@@ -129,6 +129,10 @@ message MountTableRecordProto {
     RANDOM = 2;
   }
   optional DestOrder destOrder = 6 [default = HASH];
+
+  optional string ownerName = 10;
+  optional string groupName = 11;
+  optional int32 mode = 12;
 }
 
 message AddMountTableEntryRequestProto {

hadoop-hdfs-project/hadoop-hdfs/src/main/webapps/router/federationhealth.html

@@ -335,6 +335,9 @@
       <th>Target path</th>
       <th>Order</th>
       <th>Read only</th>
+      <th>Owner</th>
+      <th>Group</th>
+      <th>Permission</th>
       <th>Date Modified</th>
       <th>Date Created</th>
     </tr>
@@ -347,6 +350,9 @@
       <td>{path}</td>
       <td>{order}</td>
       <td class="dfshealth-node-icon dfshealth-mount-read-only-{readonly}"/>
+      <td>{ownerName}</td>
+      <td>{groupName}</td>
+      <td>{mode}</td>
       <td>{dateModified}</td>
       <td>{dateCreated}</td>
     </tr>

hadoop-hdfs-project/hadoop-hdfs/src/site/markdown/HDFSCommands.md

@@ -425,7 +425,7 @@ Runs the DFS router. See [Router](./HDFSRouterFederation.html#Router) for more i
 Usage:
 
       hdfs dfsrouteradmin
-          [-add <source> <nameservice> <destination> [-readonly]]
+          [-add <source> <nameservice> <destination> [-readonly] -owner <owner> -group <group> -mode <mode>]
           [-rm <source>]
           [-ls <path>]
 

hadoop-hdfs-project/hadoop-hdfs/src/site/markdown/HDFSRouterFederation.md

@@ -190,6 +190,14 @@ It also supports mount points that disallow writes:
 
 If a mount point is not set, the Router will map it to the default namespace `dfs.federation.router.default.nameserviceId`.
 
+Mount table have UNIX-like *permissions*, which restrict which users and groups have access to the mount point. Write permissions allow users to add
+, update or remove mount point. Read permissions allow users to list mount point. Execute permissions are unused.
+
+Mount table permission can be set by following command:
+
+    [hdfs]$ $HADOOP_HOME/bin/hdfs dfsrouteradmin -add /tmp ns1 /tmp -owner root -group supergroup -mode 0755
+
+The option mode is UNIX-style permissions for the mount table. Permissions are specified in octal, e.g. 0755. By default, this is set to 0755.
 
 Client configuration
 --------------------

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/federation/metrics/TestFederationMetrics.java

@@ -84,6 +84,9 @@ public class TestFederationMetrics extends TestMetricsBase {
               json.getString("nameserviceId"));
           assertEquals(entry.getDefaultLocation().getDest(),
               json.getString("path"));
+          assertEquals(entry.getOwnerName(), json.getString("ownerName"));
+          assertEquals(entry.getGroupName(), json.getString("groupName"));
+          assertEquals(entry.getMode().toString(), json.getString("mode"));
           assertNotNullAndNotEmpty(json.getString("dateCreated"));
           assertNotNullAndNotEmpty(json.getString("dateModified"));
           match++;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/federation/router/TestRouterAdminCLI.java

@@ -0,0 +1,182 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hdfs.server.federation.router;
+
+import static org.junit.Assert.assertEquals;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import java.net.InetSocketAddress;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
+import org.apache.hadoop.hdfs.server.federation.RouterConfigBuilder;
+import org.apache.hadoop.hdfs.server.federation.RouterDFSCluster.RouterContext;
+import org.apache.hadoop.hdfs.server.federation.StateStoreDFSCluster;
+import org.apache.hadoop.hdfs.server.federation.store.StateStoreService;
+import org.apache.hadoop.hdfs.server.federation.store.impl.MountTableStoreImpl;
+import org.apache.hadoop.hdfs.server.federation.store.protocol.GetMountTableEntriesRequest;
+import org.apache.hadoop.hdfs.server.federation.store.protocol.GetMountTableEntriesResponse;
+import org.apache.hadoop.hdfs.server.federation.store.records.MountTable;
+import org.apache.hadoop.hdfs.tools.federation.RouterAdmin;
+import org.apache.hadoop.security.UserGroupInformation;
+import org.apache.hadoop.util.ToolRunner;
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+/**
+ * Tests Router admin commands.
+ */
+public class TestRouterAdminCLI {
+  private static StateStoreDFSCluster cluster;
+  private static RouterContext routerContext;
+  private static StateStoreService stateStore;
+
+  private static RouterAdmin admin;
+  private static RouterClient client;
+
+  private static final String TEST_USER = "test-user";
+
+  private final ByteArrayOutputStream out = new ByteArrayOutputStream();
+  private static final PrintStream OLD_OUT = System.out;
+
+  @BeforeClass
+  public static void globalSetUp() throws Exception {
+    cluster = new StateStoreDFSCluster(false, 1);
+    // Build and start a router with State Store + admin + RPC
+    Configuration conf = new RouterConfigBuilder()
+        .stateStore()
+        .admin()
+        .rpc()
+        .build();
+    cluster.addRouterOverrides(conf);
+
+    // Start routers
+    cluster.startRouters();
+
+    routerContext = cluster.getRandomRouter();
+    Router router = routerContext.getRouter();
+    stateStore = router.getStateStore();
+
+    Configuration routerConf = new Configuration();
+    InetSocketAddress routerSocket = router.getAdminServerAddress();
+    routerConf.setSocketAddr(DFSConfigKeys.DFS_ROUTER_ADMIN_ADDRESS_KEY,
+        routerSocket);
+    admin = new RouterAdmin(routerConf);
+    client = routerContext.getAdminClient();
+  }
+
+  @AfterClass
+  public static void tearDown() {
+    cluster.stopRouter(routerContext);
+    cluster.shutdown();
+    cluster = null;
+  }
+
+  @Test
+  public void testMountTableDefaultACL() throws Exception {
+    String[] argv = new String[] {"-add", "/testpath0", "ns0", "/testdir0"};
+    Assert.assertEquals(0, ToolRunner.run(admin, argv));
+
+    stateStore.loadCache(MountTableStoreImpl.class, true);
+    GetMountTableEntriesRequest getRequest = GetMountTableEntriesRequest
+        .newInstance("/testpath0");
+    GetMountTableEntriesResponse getResponse = client.getMountTableManager()
+        .getMountTableEntries(getRequest);
+    MountTable mountTable = getResponse.getEntries().get(0);
+
+    UserGroupInformation ugi = UserGroupInformation.getCurrentUser();
+    String group = ugi.getGroups().isEmpty() ? ugi.getShortUserName()
+        : ugi.getPrimaryGroupName();
+    assertEquals(ugi.getShortUserName(), mountTable.getOwnerName());
+    assertEquals(group, mountTable.getGroupName());
+    assertEquals((short) 0755, mountTable.getMode().toShort());
+  }
+
+  @Test
+  public void testMountTablePermissions() throws Exception {
+    // re-set system out for testing
+    System.setOut(new PrintStream(out));
+    // use superuser to add new mount table with only read permission
+    String[] argv = new String[] {"-add", "/testpath2-1", "ns0", "/testdir2-1",
+        "-owner", TEST_USER, "-group", TEST_USER, "-mode", "0455"};
+    assertEquals(0, ToolRunner.run(admin, argv));
+
+    String superUser = UserGroupInformation.
+        getCurrentUser().getShortUserName();
+    // use normal user as current user to test
+    UserGroupInformation remoteUser = UserGroupInformation
+        .createRemoteUser(TEST_USER);
+    UserGroupInformation.setLoginUser(remoteUser);
+
+    // verify read permission by executing other commands
+    verifyExecutionResult("/testpath2-1", true, -1, -1);
+
+    // add new mount table with only write permission
+    argv = new String[] {"-add", "/testpath2-2", "ns0", "/testdir2-2",
+        "-owner", TEST_USER, "-group", TEST_USER, "-mode", "0255"};
+    assertEquals(0, ToolRunner.run(admin, argv));
+    verifyExecutionResult("/testpath2-2", false, 0, 0);
+
+    // set mount table entry with read and write permission
+    argv = new String[] {"-add", "/testpath2-3", "ns0", "/testdir2-3",
+        "-owner", TEST_USER, "-group", TEST_USER, "-mode", "0755"};
+    assertEquals(0, ToolRunner.run(admin, argv));
+    verifyExecutionResult("/testpath2-3", true, 0, 0);
+
+    // set back system out and login user
+    System.setOut(OLD_OUT);
+    remoteUser = UserGroupInformation.createRemoteUser(superUser);
+    UserGroupInformation.setLoginUser(remoteUser);
+  }
+
+  /**
+   * Verify router admin commands execution result.
+   *
+   * @param mount
+   *          target mount table
+   * @param canRead
+   *          whether can list mount tables under specified mount
+   * @param addCommandCode
+   *          expected return code of add command executed for specified mount
+   * @param rmCommandCode
+   *          expected return code of rm command executed for specified mount
+   * @throws Exception
+   */
+  private void verifyExecutionResult(String mount, boolean canRead,
+      int addCommandCode, int rmCommandCode) throws Exception {
+    String[] argv = null;
+    stateStore.loadCache(MountTableStoreImpl.class, true);
+
+    out.reset();
+    // execute ls command
+    argv = new String[] {"-ls", mount};
+    assertEquals(0, ToolRunner.run(admin, argv));
+    assertEquals(canRead, out.toString().contains(mount));
+
+    // execute add/update command
+    argv = new String[] {"-add", mount, "ns0", mount + "newdir"};
+    assertEquals(addCommandCode, ToolRunner.run(admin, argv));
+
+    stateStore.loadCache(MountTableStoreImpl.class, true);
+    // execute remove command
+    argv = new String[] {"-rm", mount};
+    assertEquals(rmCommandCode, ToolRunner.run(admin, argv));
+  }
+}