HADOOP-7346. Send back nicer error message to clients using outdated IPC version. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.22@1132528 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -251,6 +251,9 @@ Release 0.22.0 - Unreleased
     HADOOP-7355  Add audience and stability annotations to HttpServer class
     (stack)
 
+    HADOOP-7346. Send back nicer error message to clients using outdated IPC
+    version. (todd)
+
     HADOOP-7335. Force entropy to come from non-true random for tests.
     (todd via eli)
 

ivy.xml

@@ -301,5 +301,9 @@
       rev="${jsch.version}"
       conf="common->default">
     </dependency>
+    <dependency org="com.google.guava"
+      name="guava"
+      rev="${guava.version}"
+      conf="common->default"/>
     </dependencies>
 </ivy-module>

ivy/libraries.properties

@@ -39,6 +39,8 @@ ftplet-api.version=1.0.0
 ftpserver-core.version=1.0.0
 ftpserver-deprecated.version=1.0.0-M2
 
+guava.version=r09
+
 hsqldb.version=1.8.0.10
 
 ivy.version=2.1.0

src/java/org/apache/hadoop/ipc/Server.java

@@ -67,6 +67,7 @@ import org.apache.hadoop.io.BytesWritable;
 import org.apache.hadoop.io.IntWritable;
 import org.apache.hadoop.io.Writable;
 import org.apache.hadoop.io.WritableUtils;
+import org.apache.hadoop.ipc.RPC.VersionMismatch;
 import org.apache.hadoop.ipc.metrics.RpcDetailedMetrics;
 import org.apache.hadoop.ipc.metrics.RpcMetrics;
 import org.apache.hadoop.security.AccessControlException;
@@ -1159,6 +1160,7 @@ public abstract class Server {
                      hostAddress + ":" + remotePort +
                      " got version " + version + 
                      " expected version " + CURRENT_VERSION);
+            setupBadVersionResponse(version);
             return -1;
           }
           dataLengthBuffer.clear();
@@ -1233,6 +1235,40 @@ public abstract class Server {
       }
     }
 
+    /**
+     * Try to set up the response to indicate that the client version
+     * is incompatible with the server. This can contain special-case
+     * code to speak enough of past IPC protocols to pass back
+     * an exception to the caller.
+     * @param clientVersion the version the caller is using 
+     * @throws IOException
+     */
+    private void setupBadVersionResponse(int clientVersion) throws IOException {
+      String errMsg = "Server IPC version " + CURRENT_VERSION +
+      " cannot communicate with client version " + clientVersion;
+      ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+      
+      if (clientVersion >= 3) {
+        Call fakeCall =  new Call(-1, null, this);
+        // Versions 3 and greater can interpret this exception
+        // response in the same manner
+        setupResponse(buffer, fakeCall, Status.FATAL,
+            null, VersionMismatch.class.getName(), errMsg);
+
+        responder.doRespond(fakeCall);
+      } else if (clientVersion == 2) { // Hadoop 0.18.3
+        Call fakeCall =  new Call(0, null, this);
+        DataOutputStream out = new DataOutputStream(buffer);
+        out.writeInt(0); // call ID
+        out.writeBoolean(true); // error
+        WritableUtils.writeString(out, VersionMismatch.class.getName());
+        WritableUtils.writeString(out, errMsg);
+        fakeCall.setResponse(ByteBuffer.wrap(buffer.toByteArray()));
+        
+        responder.doRespond(fakeCall);
+      }
+    }
+
     /// Reads the connection header following version
     private void processHeader(byte[] buf) throws IOException {
       DataInputStream in =

src/test/core/org/apache/hadoop/ipc/TestIPC.java

@@ -20,17 +20,22 @@ package org.apache.hadoop.ipc;
 
 import org.apache.commons.logging.*;
 
+import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.Writable;
 import org.apache.hadoop.io.LongWritable;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.net.NetUtils;
 
 import java.util.Random;
+import java.io.ByteArrayOutputStream;
 import java.io.DataInput;
 import java.io.File;
 import java.io.DataOutput;
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 import java.net.InetSocketAddress;
+import java.net.Socket;
 import java.net.SocketTimeoutException;
 import javax.net.SocketFactory;
 
@@ -41,6 +46,9 @@ import static org.mockito.Mockito.*;
 import org.apache.hadoop.conf.Configuration;
 import org.junit.Assume;
 
+import com.google.common.primitives.Bytes;
+import com.google.common.primitives.Ints;
+
 /** Unit tests for IPC. */
 public class TestIPC {
   public static final Log LOG =
@@ -507,6 +515,183 @@ public class TestIPC {
     return FD_DIR.list().length;
   }
 
+  @Test
+  public void testIpcFromHadoop_0_18_13() throws Exception {
+    doIpcVersionTest(NetworkTraces.HADOOP_0_18_3_RPC_DUMP,
+        NetworkTraces.RESPONSE_TO_HADOOP_0_18_3_RPC);
+  }
+  
+  @Test
+  public void testIpcFromHadoop0_20_3() throws Exception {
+    doIpcVersionTest(NetworkTraces.HADOOP_0_20_3_RPC_DUMP,
+        NetworkTraces.RESPONSE_TO_HADOOP_0_20_3_RPC);
+  }
+  
+  @Test
+  public void testIpcFromHadoop0_21_0() throws Exception {
+    doIpcVersionTest(NetworkTraces.HADOOP_0_21_0_RPC_DUMP,
+        NetworkTraces.RESPONSE_TO_HADOOP_0_21_0_RPC);
+  }
+  
+  private void doIpcVersionTest(
+      byte[] requestData,
+      byte[] expectedResponse) throws Exception {
+    Server server = new TestServer(1, true);
+    InetSocketAddress addr = NetUtils.getConnectAddress(server);
+    server.start();
+    Socket socket = new Socket();
+
+    try {
+      NetUtils.connect(socket, addr, 5000);
+      
+      OutputStream out = socket.getOutputStream();
+      InputStream in = socket.getInputStream();
+      out.write(requestData, 0, requestData.length);
+      out.flush();
+      ByteArrayOutputStream baos = new ByteArrayOutputStream();
+      IOUtils.copyBytes(in, baos, 256);
+      
+      byte[] responseData = baos.toByteArray();
+      
+      assertEquals(
+          StringUtils.byteToHexString(expectedResponse),
+          StringUtils.byteToHexString(responseData));
+    } finally {
+      IOUtils.closeSocket(socket);
+      server.stop();
+    }
+  }
+  
+  /**
+   * Convert a string of lines that look like:
+   *   "68 72 70 63 02 00 00 00  82 00 1d 6f 72 67 2e 61 hrpc.... ...org.a"
+   * .. into an array of bytes.
+   */
+  private static byte[] hexDumpToBytes(String hexdump) {
+    final int LAST_HEX_COL = 3 * 16;
+    
+    StringBuilder hexString = new StringBuilder();
+    
+    for (String line : hexdump.toUpperCase().split("\n")) {
+      hexString.append(line.substring(0, LAST_HEX_COL).replace(" ", ""));
+    }
+    return StringUtils.hexStringToByte(hexString.toString());
+  }
+  
+  /**
+   * Wireshark traces collected from various client versions. These enable
+   * us to test that old versions of the IPC stack will receive the correct
+   * responses so that they will throw a meaningful error message back
+   * to the user.
+   */
+  private static abstract class NetworkTraces {
+    /**
+     * Wireshark dump of an RPC request from Hadoop 0.18.3
+     */
+    final static byte[] HADOOP_0_18_3_RPC_DUMP =
+      hexDumpToBytes(
+      "68 72 70 63 02 00 00 00  82 00 1d 6f 72 67 2e 61 hrpc.... ...org.a\n" +
+      "70 61 63 68 65 2e 68 61  64 6f 6f 70 2e 69 6f 2e pache.ha doop.io.\n" +
+      "57 72 69 74 61 62 6c 65  00 30 6f 72 67 2e 61 70 Writable .0org.ap\n" +
+      "61 63 68 65 2e 68 61 64  6f 6f 70 2e 69 6f 2e 4f ache.had oop.io.O\n" +
+      "62 6a 65 63 74 57 72 69  74 61 62 6c 65 24 4e 75 bjectWri table$Nu\n" +
+      "6c 6c 49 6e 73 74 61 6e  63 65 00 2f 6f 72 67 2e llInstan ce./org.\n" +
+      "61 70 61 63 68 65 2e 68  61 64 6f 6f 70 2e 73 65 apache.h adoop.se\n" +
+      "63 75 72 69 74 79 2e 55  73 65 72 47 72 6f 75 70 curity.U serGroup\n" +
+      "49 6e 66 6f 72 6d 61 74  69 6f 6e 00 00 00 6c 00 Informat ion...l.\n" +
+      "00 00 00 00 12 67 65 74  50 72 6f 74 6f 63 6f 6c .....get Protocol\n" +
+      "56 65 72 73 69 6f 6e 00  00 00 02 00 10 6a 61 76 Version. .....jav\n" +
+      "61 2e 6c 61 6e 67 2e 53  74 72 69 6e 67 00 2e 6f a.lang.S tring..o\n" +
+      "72 67 2e 61 70 61 63 68  65 2e 68 61 64 6f 6f 70 rg.apach e.hadoop\n" +
+      "2e 6d 61 70 72 65 64 2e  4a 6f 62 53 75 62 6d 69 .mapred. JobSubmi\n" +
+      "73 73 69 6f 6e 50 72 6f  74 6f 63 6f 6c 00 04 6c ssionPro tocol..l\n" +
+      "6f 6e 67 00 00 00 00 00  00 00 0a                ong..... ...     \n");
+
+    final static String HADOOP0_18_ERROR_MSG =
+      "Server IPC version " + Server.CURRENT_VERSION +
+      " cannot communicate with client version 2";
+    
+    /**
+     * Wireshark dump of the correct response that triggers an error message
+     * on an 0.18.3 client.
+     */
+    final static byte[] RESPONSE_TO_HADOOP_0_18_3_RPC =
+      Bytes.concat(hexDumpToBytes(
+      "00 00 00 00 01 00 00 00  29 6f 72 67 2e 61 70 61 ........ )org.apa\n" +
+      "63 68 65 2e 68 61 64 6f  6f 70 2e 69 70 63 2e 52 che.hado op.ipc.R\n" +
+      "50 43 24 56 65 72 73 69  6f 6e 4d 69 73 6d 61 74 PC$Versi onMismat\n" +
+      "63 68                                            ch               \n"),
+       Ints.toByteArray(HADOOP0_18_ERROR_MSG.length()),
+       HADOOP0_18_ERROR_MSG.getBytes());
+    
+    /**
+     * Wireshark dump of an RPC request from Hadoop 0.20.3
+     */
+    final static byte[] HADOOP_0_20_3_RPC_DUMP =
+      hexDumpToBytes(
+      "68 72 70 63 03 00 00 00  79 27 6f 72 67 2e 61 70 hrpc.... y'org.ap\n" +
+      "61 63 68 65 2e 68 61 64  6f 6f 70 2e 69 70 63 2e ache.had oop.ipc.\n" +
+      "56 65 72 73 69 6f 6e 65  64 50 72 6f 74 6f 63 6f Versione dProtoco\n" +
+      "6c 01 0a 53 54 52 49 4e  47 5f 55 47 49 04 74 6f l..STRIN G_UGI.to\n" +
+      "64 64 09 04 74 6f 64 64  03 61 64 6d 07 64 69 61 dd..todd .adm.dia\n" +
+      "6c 6f 75 74 05 63 64 72  6f 6d 07 70 6c 75 67 64 lout.cdr om.plugd\n" +
+      "65 76 07 6c 70 61 64 6d  69 6e 05 61 64 6d 69 6e ev.lpadm in.admin\n" +
+      "0a 73 61 6d 62 61 73 68  61 72 65 06 6d 72 74 65 .sambash are.mrte\n" +
+      "73 74 00 00 00 6c 00 00  00 00 00 12 67 65 74 50 st...l.. ....getP\n" +
+      "72 6f 74 6f 63 6f 6c 56  65 72 73 69 6f 6e 00 00 rotocolV ersion..\n" +
+      "00 02 00 10 6a 61 76 61  2e 6c 61 6e 67 2e 53 74 ....java .lang.St\n" +
+      "72 69 6e 67 00 2e 6f 72  67 2e 61 70 61 63 68 65 ring..or g.apache\n" +
+      "2e 68 61 64 6f 6f 70 2e  6d 61 70 72 65 64 2e 4a .hadoop. mapred.J\n" +
+      "6f 62 53 75 62 6d 69 73  73 69 6f 6e 50 72 6f 74 obSubmis sionProt\n" +
+      "6f 63 6f 6c 00 04 6c 6f  6e 67 00 00 00 00 00 00 ocol..lo ng......\n" +
+      "00 14                                            ..               \n");
+
+    final static String HADOOP0_20_ERROR_MSG =
+      "Server IPC version " + Server.CURRENT_VERSION +
+      " cannot communicate with client version 3";
+    
+
+    final static byte[] RESPONSE_TO_HADOOP_0_20_3_RPC =
+      Bytes.concat(hexDumpToBytes(
+      "ff ff ff ff ff ff ff ff  00 00 00 29 6f 72 67 2e ........ ...)org.\n" +
+      "61 70 61 63 68 65 2e 68  61 64 6f 6f 70 2e 69 70 apache.h adoop.ip\n" +
+      "63 2e 52 50 43 24 56 65  72 73 69 6f 6e 4d 69 73 c.RPC$Ve rsionMis\n" +
+      "6d 61 74 63 68                                   match            \n"),
+      Ints.toByteArray(HADOOP0_20_ERROR_MSG.length()),
+      HADOOP0_20_ERROR_MSG.getBytes());
+    
+    
+    final static String HADOOP0_21_ERROR_MSG =
+      "Server IPC version " + Server.CURRENT_VERSION +
+      " cannot communicate with client version 4";
+
+    final static byte[] HADOOP_0_21_0_RPC_DUMP =
+      hexDumpToBytes(
+      "68 72 70 63 04 50                                hrpc.P" +
+      // in 0.21 it comes in two separate TCP packets
+      "00 00 00 3c 33 6f 72 67  2e 61 70 61 63 68 65 2e ...<3org .apache.\n" +
+      "68 61 64 6f 6f 70 2e 6d  61 70 72 65 64 75 63 65 hadoop.m apreduce\n" +
+      "2e 70 72 6f 74 6f 63 6f  6c 2e 43 6c 69 65 6e 74 .protoco l.Client\n" +
+      "50 72 6f 74 6f 63 6f 6c  01 00 04 74 6f 64 64 00 Protocol ...todd.\n" +
+      "00 00 00 71 00 00 00 00  00 12 67 65 74 50 72 6f ...q.... ..getPro\n" +
+      "74 6f 63 6f 6c 56 65 72  73 69 6f 6e 00 00 00 02 tocolVer sion....\n" +
+      "00 10 6a 61 76 61 2e 6c  61 6e 67 2e 53 74 72 69 ..java.l ang.Stri\n" +
+      "6e 67 00 33 6f 72 67 2e  61 70 61 63 68 65 2e 68 ng.3org. apache.h\n" +
+      "61 64 6f 6f 70 2e 6d 61  70 72 65 64 75 63 65 2e adoop.ma preduce.\n" +
+      "70 72 6f 74 6f 63 6f 6c  2e 43 6c 69 65 6e 74 50 protocol .ClientP\n" +
+      "72 6f 74 6f 63 6f 6c 00  04 6c 6f 6e 67 00 00 00 rotocol. .long...\n" +
+      "00 00 00 00 21                                   ....!            \n");
+    
+    final static byte[] RESPONSE_TO_HADOOP_0_21_0_RPC =
+      Bytes.concat(hexDumpToBytes(
+      "ff ff ff ff ff ff ff ff  00 00 00 29 6f 72 67 2e ........ ...)org.\n" +
+      "61 70 61 63 68 65 2e 68  61 64 6f 6f 70 2e 69 70 apache.h adoop.ip\n" +
+      "63 2e 52 50 43 24 56 65  72 73 69 6f 6e 4d 69 73 c.RPC$Ve rsionMis\n" +
+      "6d 61 74 63 68                                   match            \n"),
+      Ints.toByteArray(HADOOP0_21_ERROR_MSG.length()),
+      HADOOP0_21_ERROR_MSG.getBytes());
+  }
+
   public static void main(String[] args) throws Exception {
 
     //new TestIPC().testSerial(5, false, 2, 10, 1000);