HDFS-6281. Provide option to use the NFS Gateway without having to use the Hadoop portmapper. Contributed by Aaron T. Myers.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1589914 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-nfs/src/main/java/org/apache/hadoop/oncrpc/RpcProgram.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.oncrpc;
 
 import java.io.IOException;
+import java.net.DatagramSocket;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -45,6 +46,12 @@ public abstract class RpcProgram extends SimpleChannelUpstreamHandler {
   private final int lowProgVersion;
   private final int highProgVersion;
   
+  /**
+   * If not null, this will be used as the socket to use to connect to the
+   * system portmap daemon when registering this RPC server program.
+   */
+  private final DatagramSocket registrationSocket;
+  
   /**
    * Constructor
    * 
@@ -56,13 +63,15 @@ public abstract class RpcProgram extends SimpleChannelUpstreamHandler {
    * @param highProgVersion highest version of the specification supported
    */
   protected RpcProgram(String program, String host, int port, int progNumber,
-      int lowProgVersion, int highProgVersion) {
+      int lowProgVersion, int highProgVersion,
+      DatagramSocket registrationSocket) {
     this.program = program;
     this.host = host;
     this.port = port;
     this.progNumber = progNumber;
     this.lowProgVersion = lowProgVersion;
     this.highProgVersion = highProgVersion;
+    this.registrationSocket = registrationSocket;
   }
 
   /**
@@ -105,14 +114,14 @@ public void unregister(int transport, int boundPort) {
   protected void register(PortmapMapping mapEntry, boolean set) {
     XDR mappingRequest = PortmapRequest.create(mapEntry, set);
     SimpleUdpClient registrationClient = new SimpleUdpClient(host, RPCB_PORT,
-        mappingRequest);
+        mappingRequest, registrationSocket);
     try {
       registrationClient.run();
     } catch (IOException e) {
       String request = set ? "Registration" : "Unregistration";
       LOG.error(request + " failure with " + host + ":" + port
-          + ", portmap entry: " + mapEntry);
-      throw new RuntimeException(request + " failure");
+          + ", portmap entry: " + mapEntry, e);
+      throw new RuntimeException(request + " failure", e);
     }
   }
 

hadoop-common-project/hadoop-nfs/src/main/java/org/apache/hadoop/oncrpc/SimpleUdpClient.java

@@ -27,34 +27,42 @@
  * A simple UDP based RPC client which just sends one request to a server.
  */
 public class SimpleUdpClient {
+  
   protected final String host;
   protected final int port;
   protected final XDR request;
   protected final boolean oneShot;
+  protected final DatagramSocket clientSocket;
 
-  public SimpleUdpClient(String host, int port, XDR request) {
-    this(host, port, request, true);
+  public SimpleUdpClient(String host, int port, XDR request,
+      DatagramSocket clientSocket) {
+    this(host, port, request, true, clientSocket);
   }
 
-  public SimpleUdpClient(String host, int port, XDR request, Boolean oneShot) {
+  public SimpleUdpClient(String host, int port, XDR request, Boolean oneShot,
+      DatagramSocket clientSocket) {
     this.host = host;
     this.port = port;
     this.request = request;
     this.oneShot = oneShot;
+    this.clientSocket = clientSocket;
   }
 
   public void run() throws IOException {
-    DatagramSocket clientSocket = new DatagramSocket();
     InetAddress IPAddress = InetAddress.getByName(host);
     byte[] sendData = request.getBytes();
     byte[] receiveData = new byte[65535];
+    // Use the provided socket if there is one, else just make a new one.
+    DatagramSocket socket = this.clientSocket == null ?
+        new DatagramSocket() : this.clientSocket;
 
+    try {
       DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length,
           IPAddress, port);
-    clientSocket.send(sendPacket);
+      socket.send(sendPacket);
       DatagramPacket receivePacket = new DatagramPacket(receiveData,
           receiveData.length);
-    clientSocket.receive(receivePacket);
+      socket.receive(receivePacket);
   
       // Check reply status
       XDR xdr = new XDR(Arrays.copyOfRange(receiveData, 0,
@@ -63,7 +71,12 @@ public void run() throws IOException {
       if (reply.getState() != RpcReply.ReplyState.MSG_ACCEPTED) {
         throw new IOException("Request failed: " + reply.getState());
       }
-
-    clientSocket.close();
+    } finally {
+      // If the client socket was passed in to this UDP client, it's on the
+      // caller of this UDP client to close that socket.
+      if (this.clientSocket == null) {
+        socket.close();
+      }
+    }
   }
 }

hadoop-common-project/hadoop-nfs/src/test/java/org/apache/hadoop/oncrpc/TestFrameDecoder.java

@@ -51,7 +51,8 @@ static class TestRpcProgram extends RpcProgram {
 
     protected TestRpcProgram(String program, String host, int port,
         int progNumber, int lowProgVersion, int highProgVersion) {
-      super(program, host, port, progNumber, lowProgVersion, highProgVersion);
+      super(program, host, port, progNumber, lowProgVersion, highProgVersion,
+          null);
     }
 
     @Override

hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/mount/Mountd.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hdfs.nfs.mount;
 
 import java.io.IOException;
+import java.net.DatagramSocket;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.mount.MountdBase;
@@ -31,13 +32,14 @@
  */
 public class Mountd extends MountdBase {
 
-  public Mountd(Configuration config) throws IOException {
-    super(new RpcProgramMountd(config));
+  public Mountd(Configuration config, DatagramSocket registrationSocket)
+      throws IOException {
+    super(new RpcProgramMountd(config, registrationSocket));
   }
   
   public static void main(String[] args) throws IOException {
     Configuration config = new Configuration();
-    Mountd mountd = new Mountd(config);
+    Mountd mountd = new Mountd(config, null);
     mountd.start(true);
   }
 }

hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/mount/RpcProgramMountd.java

@@ -20,6 +20,7 @@
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NFS_KERBEROS_PRINCIPAL_KEY;
 
 import java.io.IOException;
+import java.net.DatagramSocket;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.util.ArrayList;
@@ -78,10 +79,11 @@ public class RpcProgramMountd extends RpcProgram implements MountInterface {
   
   private final NfsExports hostsMatcher;
 
-  public RpcProgramMountd(Configuration config) throws IOException {
+  public RpcProgramMountd(Configuration config,
+      DatagramSocket registrationSocket) throws IOException {
     // Note that RPC cache is not enabled
     super("mountd", "localhost", config.getInt("nfs3.mountd.port", PORT),
-        PROGRAM, VERSION_1, VERSION_3);
+        PROGRAM, VERSION_1, VERSION_3, registrationSocket);
     exports = new ArrayList<String>();
     exports.add(config.get(Nfs3Constant.EXPORT_POINT,
         Nfs3Constant.EXPORT_POINT_DEFAULT));

hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/Nfs3.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hdfs.nfs.nfs3;
 
 import java.io.IOException;
+import java.net.DatagramSocket;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.nfs.mount.Mountd;
@@ -40,8 +41,12 @@ public class Nfs3 extends Nfs3Base {
   }
   
   public Nfs3(Configuration conf) throws IOException {
-    super(new RpcProgramNfs3(conf), conf);
-    mountd = new Mountd(conf);
+    this(conf, null);
+  }
+  
+  public Nfs3(Configuration conf, DatagramSocket registrationSocket) throws IOException {
+    super(new RpcProgramNfs3(conf, registrationSocket), conf);
+    mountd = new Mountd(conf, registrationSocket);
   }
 
   public Mountd getMountd() {
@@ -54,9 +59,14 @@ public void startServiceInternal(boolean register) throws IOException {
     start(register);
   }
   
-  public static void main(String[] args) throws IOException {
+  static void startService(String[] args,
+      DatagramSocket registrationSocket) throws IOException {
     StringUtils.startupShutdownMessage(Nfs3.class, args, LOG);    
-    final Nfs3 nfsServer = new Nfs3(new Configuration());
+    final Nfs3 nfsServer = new Nfs3(new Configuration(), registrationSocket);
     nfsServer.startServiceInternal(true);
   }
+  
+  public static void main(String[] args) throws IOException {
+    startService(args, null);
+  }
 }

hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/PrivilegedNfsGatewayStarter.java

@@ -0,0 +1,76 @@
+/**
+ * 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.nfs.nfs3;
+
+import java.net.DatagramSocket;
+import java.net.InetSocketAddress;
+
+import org.apache.commons.daemon.Daemon;
+import org.apache.commons.daemon.DaemonContext;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
+import org.apache.hadoop.hdfs.HdfsConfiguration;
+
+/**
+ * This class is used to allow the initial registration of the NFS gateway with
+ * the system portmap daemon to come from a privileged (< 1024) port. This is
+ * necessary on certain operating systems to work around this bug in rpcbind:
+ * 
+ * Red Hat: https://bugzilla.redhat.com/show_bug.cgi?id=731542
+ * SLES: https://bugzilla.novell.com/show_bug.cgi?id=823364
+ * Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=594880
+ */
+public class PrivilegedNfsGatewayStarter implements Daemon {
+	
+  private String[] args = null;
+  private DatagramSocket registrationSocket = null;
+
+  @Override
+  public void init(DaemonContext context) throws Exception {
+    System.err.println("Initializing privileged NFS client socket...");
+    Configuration conf = new HdfsConfiguration();
+    int clientPort = conf.getInt(DFSConfigKeys.DFS_NFS_REGISTRATION_PORT_KEY,
+        DFSConfigKeys.DFS_NFS_REGISTRATION_PORT_DEFAULT);
+    if (clientPort < 1 || clientPort > 1023) {
+      throw new RuntimeException("Must start privileged NFS server with '" +
+          DFSConfigKeys.DFS_NFS_REGISTRATION_PORT_KEY + "' configured to a " +
+          "privileged port.");
+    }
+    registrationSocket = new DatagramSocket(
+        new InetSocketAddress("localhost", clientPort));
+    registrationSocket.setReuseAddress(true);
+    args = context.getArguments();
+  }
+
+  @Override
+  public void start() throws Exception {
+    Nfs3.startService(args, registrationSocket);
+  }
+
+  @Override
+  public void stop() throws Exception {
+    // Nothing to do.
+  }
+
+  @Override
+  public void destroy() {
+    if (registrationSocket != null && !registrationSocket.isClosed()) {
+      registrationSocket.close();
+    }
+  }
+
+}

hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/RpcProgramNfs3.java

@@ -20,6 +20,7 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.net.DatagramSocket;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.nio.ByteBuffer;
@@ -165,10 +166,11 @@ public class RpcProgramNfs3 extends RpcProgram implements Nfs3Interface {
   
   private final RpcCallCache rpcCallCache;
 
-  public RpcProgramNfs3(Configuration config) throws IOException {
+  public RpcProgramNfs3(Configuration config, DatagramSocket registrationSocket)
+      throws IOException {
     super("NFS3", "localhost", config.getInt(Nfs3Constant.NFS3_SERVER_PORT,
         Nfs3Constant.NFS3_SERVER_PORT_DEFAULT), Nfs3Constant.PROGRAM,
-        Nfs3Constant.VERSION, Nfs3Constant.VERSION);
+        Nfs3Constant.VERSION, Nfs3Constant.VERSION, registrationSocket);
    
     config.set(FsPermission.UMASK_LABEL, "000");
     iug = new IdUserGroup();

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

@@ -260,6 +260,9 @@ Release 2.5.0 - UNRELEASED
 
   NEW FEATURES
 
+    HDFS-6281. Provide option to use the NFS Gateway without having to use the
+    Hadoop portmapper. (atm)
+
   IMPROVEMENTS
 
     HDFS-6007. Update documentation about short-circuit local reads (iwasakims

hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs

@@ -101,6 +101,27 @@ if [ "$COMMAND" == "datanode" ] && [ "$EUID" -eq 0 ] && [ -n "$HADOOP_SECURE_DN_
   fi
 fi
 
+# Determine if we're starting a privileged NFS daemon, and if so, redefine appropriate variables
+if [ "$COMMAND" == "nfs3" ] && [ "$EUID" -eq 0 ] && [ -n "$HADOOP_PRIVILEGED_NFS_USER" ]; then
+  if [ -n "$JSVC_HOME" ]; then
+    if [ -n "$HADOOP_PRIVILEGED_NFS_PID_DIR" ]; then
+      HADOOP_PID_DIR=$HADOOP_PRIVILEGED_NFS_PID_DIR
+    fi
+  
+    if [ -n "$HADOOP_PRIVILEGED_NFS_LOG_DIR" ]; then
+      HADOOP_LOG_DIR=$HADOOP_PRIVILEGED_NFS_LOG_DIR
+      HADOOP_OPTS="$HADOOP_OPTS -Dhadoop.log.dir=$HADOOP_LOG_DIR"
+    fi
+   
+    HADOOP_IDENT_STRING=$HADOOP_PRIVILEGED_NFS_USER
+    HADOOP_OPTS="$HADOOP_OPTS -Dhadoop.id.str=$HADOOP_IDENT_STRING"
+    starting_privileged_nfs="true"
+  else
+    echo "It looks like you're trying to start a privileged NFS server, but"\
+      "\$JSVC_HOME isn't set. Falling back to starting unprivileged NFS server."
+  fi
+fi
+
 if [ "$COMMAND" = "namenode" ] ; then
   CLASS='org.apache.hadoop.hdfs.server.namenode.NameNode'
   HADOOP_OPTS="$HADOOP_OPTS $HADOOP_NAMENODE_OPTS"
@@ -178,7 +199,7 @@ if [ "$starting_secure_dn" = "true" ]; then
 
   JSVC=$JSVC_HOME/jsvc
   if [ ! -f $JSVC ]; then
-    echo "JSVC_HOME is not set correctly so jsvc cannot be found. Jsvc is required to run secure datanodes. "
+    echo "JSVC_HOME is not set correctly so jsvc cannot be found. jsvc is required to run secure datanodes. "
     echo "Please download and install jsvc from http://archive.apache.org/dist/commons/daemon/binaries/ "\
       "and set JSVC_HOME to the directory containing the jsvc binary."
     exit
@@ -201,6 +222,38 @@ if [ "$starting_secure_dn" = "true" ]; then
             -cp "$CLASSPATH" \
            $JAVA_HEAP_MAX $HADOOP_OPTS \
            org.apache.hadoop.hdfs.server.datanode.SecureDataNodeStarter "$@"
+elif [ "$starting_privileged_nfs" = "true" ] ; then
+  if [ "$HADOOP_PID_DIR" = "" ]; then
+    HADOOP_PRIVILEGED_NFS_PID="/tmp/hadoop_privileged_nfs3.pid"
+  else
+    HADOOP_PRIVILEGED_NFS_PID="$HADOOP_PID_DIR/hadoop_privileged_nfs3.pid"
+  fi
+
+  JSVC=$JSVC_HOME/jsvc
+  if [ ! -f $JSVC ]; then
+    echo "JSVC_HOME is not set correctly so jsvc cannot be found. jsvc is required to run privileged NFS gateways. "
+    echo "Please download and install jsvc from http://archive.apache.org/dist/commons/daemon/binaries/ "\
+      "and set JSVC_HOME to the directory containing the jsvc binary."
+    exit
+  fi
+
+  if [[ ! $JSVC_OUTFILE ]]; then
+    JSVC_OUTFILE="$HADOOP_LOG_DIR/nfs3_jsvc.out"
+  fi
+
+  if [[ ! $JSVC_ERRFILE ]]; then
+    JSVC_ERRFILE="$HADOOP_LOG_DIR/nfs3_jsvc.err"
+  fi
+
+  exec "$JSVC" \
+           -Dproc_$COMMAND -outfile "$JSVC_OUTFILE" \
+           -errfile "$JSVC_ERRFILE" \
+           -pidfile "$HADOOP_PRIVILEGED_NFS_PID" \
+           -nodetach \
+           -user "$HADOOP_PRIVILEGED_NFS_USER" \
+           -cp "$CLASSPATH" \
+           $JAVA_HEAP_MAX $HADOOP_OPTS \
+           org.apache.hadoop.hdfs.nfs.nfs3.PrivilegedNfsGatewayStarter "$@"
 else
   # run it
   exec "$JAVA" -Dproc_$COMMAND $JAVA_HEAP_MAX $HADOOP_OPTS $CLASS "$@"

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

@@ -631,4 +631,6 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
   public static final int    DEFAULT_DFSCLIENT_HEDGED_READ_THREADPOOL_SIZE = 0;
   public static final String DFS_NFS_KEYTAB_FILE_KEY = "dfs.nfs.keytab.file";
   public static final String DFS_NFS_KERBEROS_PRINCIPAL_KEY = "dfs.nfs.kerberos.principal";
+  public static final String DFS_NFS_REGISTRATION_PORT_KEY = "dfs.nfs.registration.port";
+  public static final int    DFS_NFS_REGISTRATION_PORT_DEFAULT = 40; // Currently unassigned.
 }

hadoop-hdfs-project/hadoop-hdfs/src/site/apt/HdfsNfsGateway.apt.vm

@@ -243,6 +243,19 @@ HDFS NFS Gateway
       hadoop-daemon.sh stop portmap
 -------------------------
 
+  Optionally, you can forgo running the Hadoop-provided portmap daemon and
+  instead use the system portmap daemon on all operating systems if you start the
+  NFS Gateway as root. This will allow the HDFS NFS Gateway to work around the
+  aforementioned bug and still register using the system portmap daemon. To do
+  so, just start the NFS gateway daemon as you normally would, but make sure to
+  do so as the "root" user, and also set the "HADOOP_PRIVILEGED_NFS_USER"
+  environment variable to an unprivileged user. In this mode the NFS Gateway will
+  start as root to perform its initial registration with the system portmap, and
+  then will drop privileges back to the user specified by the
+  HADOOP_PRIVILEGED_NFS_USER afterward and for the rest of the duration of the
+  lifetime of the NFS Gateway process. Note that if you choose this route, you
+  should skip steps 1 and 2 above.
+
 
 * {Verify validity of NFS related services}