From 3ba985997d1dc37e5ba017dd0ab1d36083b5f77b Mon Sep 17 00:00:00 2001
From: Xiaoyu Yao <xyao@apache.org>
Date: Wed, 3 Jan 2018 14:54:20 -0800
Subject: [PATCH] HDFS-12931. Handle InvalidEncryptionKeyException during
 DistributedFileSystem#getFileChecksum. Contributed by Mukul Kumar Singh.

---
 .../hadoop/hdfs/FileChecksumHelper.java       | 15 +++++-
 .../hadoop/hdfs/TestEncryptedTransfer.java    | 52 +++++++++++++++++++
 2 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/FileChecksumHelper.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/FileChecksumHelper.java
index 689d46d822..72cf147a08 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/FileChecksumHelper.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/FileChecksumHelper.java
@@ -33,6 +33,7 @@
 import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Op;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
+import org.apache.hadoop.hdfs.protocol.datatransfer.InvalidEncryptionKeyException;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.BlockOpResponseProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpBlockChecksumResponseProto;
 import org.apache.hadoop.hdfs.protocolPB.PBHelperClient;
@@ -303,8 +304,7 @@ void checksumBlocks() throws IOException {
      * Return true when sounds good to continue or retry, false when severe
      * condition or totally failed.
      */
-    private boolean checksumBlock(
-        LocatedBlock locatedBlock) throws IOException {
+    private boolean checksumBlock(LocatedBlock locatedBlock) {
       ExtendedBlock block = locatedBlock.getBlock();
       if (getRemaining() < block.getNumBytes()) {
         block.setNumBytes(getRemaining());
@@ -334,6 +334,17 @@ private boolean checksumBlock(
             blockIdx--; // repeat at blockIdx-th block
             setRefetchBlocks(true);
           }
+        } catch (InvalidEncryptionKeyException iee) {
+          if (blockIdx > getLastRetriedIndex()) {
+            LOG.debug("Got invalid encryption key error in response to "
+                    + "OP_BLOCK_CHECKSUM for file {} for block {} from "
+                    + "datanode {}. Will retry " + "the block once.",
+                  getSrc(), block, datanodes[j]);
+            setLastRetriedIndex(blockIdx);
+            done = true; // actually it's not done; but we'll retry
+            blockIdx--; // repeat at i-th block
+            getClient().clearDataEncryptionKey();
+          }
         } catch (IOException ie) {
           LOG.warn("src={}" + ", datanodes[{}]={}",
               getSrc(), j, datanodes[j], ie);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptedTransfer.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptedTransfer.java
index cc90863729..27a5b77bcf 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptedTransfer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptedTransfer.java
@@ -59,6 +59,7 @@
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
+import org.junit.Assert;
 import org.junit.rules.Timeout;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
@@ -318,6 +319,57 @@ public void testLongLivedClient() throws IOException, InterruptedException {
     assertEquals(checksum, fs.getFileChecksum(TEST_PATH));
   }
 
+  @Test
+  public void testFileChecksumWithInvalidEncryptionKey()
+      throws IOException, InterruptedException, TimeoutException {
+    if (resolverClazz != null) {
+      // TestTrustedChannelResolver does not use encryption keys.
+      return;
+    }
+    setEncryptionConfigKeys();
+    cluster = new MiniDFSCluster.Builder(conf).build();
+
+    fs = getFileSystem(conf);
+    DFSClient client = DFSClientAdapter.getDFSClient((DistributedFileSystem)fs);
+    DFSClient spyClient = Mockito.spy(client);
+    DFSClientAdapter.setDFSClient((DistributedFileSystem) fs, spyClient);
+    writeTestDataToFile(fs);
+    FileChecksum checksum = fs.getFileChecksum(TEST_PATH);
+
+    BlockTokenSecretManager btsm = cluster.getNamesystem().getBlockManager()
+        .getBlockTokenSecretManager();
+    // Reduce key update interval and token life for testing.
+    btsm.setKeyUpdateIntervalForTesting(2 * 1000);
+    btsm.setTokenLifetime(2 * 1000);
+    btsm.clearAllKeysForTesting();
+
+    // Wait until the encryption key becomes invalid.
+    LOG.info("Wait until encryption keys become invalid...");
+
+    DataEncryptionKey encryptionKey = spyClient.getEncryptionKey();
+    List<DataNode> dataNodes = cluster.getDataNodes();
+    for (DataNode dn: dataNodes) {
+      GenericTestUtils.waitFor(
+          new Supplier<Boolean>() {
+            @Override
+            public Boolean get() {
+              return !dn.getBlockPoolTokenSecretManager().
+                  get(encryptionKey.blockPoolId)
+                  .hasKey(encryptionKey.keyId);
+            }
+          }, 100, 30*1000
+      );
+    }
+    LOG.info("The encryption key is invalid on all nodes now.");
+    fs.getFileChecksum(TEST_PATH);
+    // verify that InvalidEncryptionKeyException is handled properly
+    Assert.assertTrue(client.getEncryptionKey() == null);
+    Mockito.verify(spyClient, times(1)).clearDataEncryptionKey();
+    // Retry the operation after clearing the encryption key
+    FileChecksum verifyChecksum = fs.getFileChecksum(TEST_PATH);
+    Assert.assertEquals(checksum, verifyChecksum);
+  }
+
   @Test
   public void testLongLivedClientPipelineRecovery()
       throws IOException, InterruptedException, TimeoutException {