/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.namenode;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import com.google.common.base.Supplier;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.crypto.key.JavaKeyStoreProvider;
import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
import org.apache.hadoop.fs.FileContext;
import org.apache.hadoop.fs.FileContextTestWrapper;
import org.apache.hadoop.fs.FileEncryptionInfo;
import org.apache.hadoop.fs.FileSystemTestHelper;
import org.apache.hadoop.fs.FileSystemTestWrapper;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RemoteIterator;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.client.CreateEncryptionZoneFlag;
import org.apache.hadoop.hdfs.client.HdfsAdmin;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.ReencryptAction;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
import org.apache.hadoop.hdfs.protocol.ReencryptionStatus;
import org.apache.hadoop.hdfs.protocol.SnapshotAccessControlException;
import org.apache.hadoop.hdfs.protocol.ZoneReencryptionStatus;
import org.apache.hadoop.hdfs.server.namenode.ReencryptionUpdater.ZoneSubmissionTracker;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.ipc.RetriableException;
import org.apache.hadoop.test.GenericTestUtils;
import org.junit.After;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;

import static org.apache.hadoop.test.GenericTestUtils.assertExceptionContains;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotEquals;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import org.junit.rules.Timeout;
import org.mockito.internal.util.reflection.Whitebox;
import org.slf4j.LoggerFactory;
import org.slf4j.event.Level;

/**
 * Test class for re-encryption.
 */
public class TestReencryption {

  protected static final org.slf4j.Logger LOG =
      LoggerFactory.getLogger(TestReencryption.class);

  private Configuration conf;
  private FileSystemTestHelper fsHelper;

  private MiniDFSCluster cluster;
  private HdfsAdmin dfsAdmin;
  private DistributedFileSystem fs;
  private FSNamesystem fsn;
  private File testRootDir;
  private static final String TEST_KEY = "test_key";

  private FileSystemTestWrapper fsWrapper;
  private FileContextTestWrapper fcWrapper;

  private static final EnumSet<CreateEncryptionZoneFlag> NO_TRASH =
      EnumSet.of(CreateEncryptionZoneFlag.NO_TRASH);

  private String getKeyProviderURI() {
    return JavaKeyStoreProvider.SCHEME_NAME + "://file" + new Path(
        testRootDir.toString(), "test.jks").toUri();
  }

  @Rule
  public Timeout globalTimeout = new Timeout(180 * 1000);

  @Before
  public void setup() throws Exception {
    conf = new HdfsConfiguration();
    fsHelper = new FileSystemTestHelper();
    // Set up java key store
    String testRoot = fsHelper.getTestRootDir();
    testRootDir = new File(testRoot).getAbsoluteFile();
    conf.set(CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH,
        getKeyProviderURI());
    conf.setBoolean(DFSConfigKeys.DFS_NAMENODE_DELEGATION_TOKEN_ALWAYS_USE_KEY,
        true);
    // Lower the batch size for testing
    conf.setInt(DFSConfigKeys.DFS_NAMENODE_LIST_ENCRYPTION_ZONES_NUM_RESPONSES,
        2);
    // Lower the listing limit for testing
    conf.setInt(DFSConfigKeys.DFS_LIST_LIMIT, 3);
    // Adjust configs for re-encrypt test cases
    conf.setInt(DFSConfigKeys.DFS_NAMENODE_REENCRYPT_BATCH_SIZE_KEY, 5);
    conf.setTimeDuration(
        DFSConfigKeys.DFS_NAMENODE_REENCRYPT_SLEEP_INTERVAL_KEY, 1,
        TimeUnit.SECONDS);
    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
    cluster.waitActive();
    fs = cluster.getFileSystem();
    fsn = cluster.getNamesystem();
    fsWrapper = new FileSystemTestWrapper(fs);
    fcWrapper = new FileContextTestWrapper(
        FileContext.getFileContext(cluster.getURI(), conf));
    dfsAdmin = new HdfsAdmin(cluster.getURI(), conf);
    setProvider();
    // Create a test key
    DFSTestUtil.createKey(TEST_KEY, cluster, conf);
    GenericTestUtils.setLogLevel(EncryptionZoneManager.LOG, Level.TRACE);
    GenericTestUtils.setLogLevel(ReencryptionHandler.LOG, Level.TRACE);
    GenericTestUtils.setLogLevel(ReencryptionStatus.LOG, Level.TRACE);
    GenericTestUtils.setLogLevel(ReencryptionUpdater.LOG, Level.TRACE);
  }

  private void setProvider() {
    // Need to set the client's KeyProvider to the NN's for JKS,
    // else the updates do not get flushed properly
    fs.getClient()
        .setKeyProvider(cluster.getNameNode().getNamesystem().getProvider());
  }

  @After
  public void teardown() {
    if (cluster != null) {
      cluster.shutdown();
      cluster = null;
    }
    EncryptionFaultInjector.instance = new EncryptionFaultInjector();
  }

  private FileEncryptionInfo getFileEncryptionInfo(Path path) throws Exception {
    return fsn.getFileInfo(path.toString(), false).getFileEncryptionInfo();
  }

  @Test
  public void testReencryptionBasic() throws Exception {
    /* Setup test dir:
     * /zones/zone/[0-9]
     * /dir/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path("/dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    // test re-encrypt without keyroll
    final Path encFile1 = new Path(zone, "0");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile1);
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);
    assertKeyVersionEquals(encFile1, fei0);
    // key not rolled, so no edeks need to be updated.
    verifyZoneStatus(zone, null, 0);

    // test re-encrypt after keyroll
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(2);
    FileEncryptionInfo fei1 = getFileEncryptionInfo(encFile1);
    assertKeyVersionChanged(encFile1, fei0);

    // test listReencryptionStatus
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    assertNotEquals(fei0.getEzKeyVersionName(), zs.getEzKeyVersionName());
    assertEquals(fei1.getEzKeyVersionName(), zs.getEzKeyVersionName());
    assertEquals(10, zs.getFilesReencrypted());

    // test re-encrypt on same zone again
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(3);
    assertKeyVersionEquals(encFile1, fei1);

    // test non-EZ submission
    try {
      dfsAdmin.reencryptEncryptionZone(subdir, ReencryptAction.START);
      fail("Re-encrypting non-EZ should fail");
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertExceptionContains("not the root of an encryption zone", expected);
    }

    // test non-existing dir
    try {
      dfsAdmin.reencryptEncryptionZone(new Path(zone, "notexist"),
          ReencryptAction.START);
      fail("Re-encrypting non-existing dir should fail");
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertTrue(
          expected.unwrapRemoteException() instanceof FileNotFoundException);
    }

    // test directly on a EZ file
    try {
      dfsAdmin.reencryptEncryptionZone(encFile1, ReencryptAction.START);
      fail("Re-encrypting on a file should fail");
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertExceptionContains("not the root of an encryption zone", expected);
    }

    // test same command resubmission
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);
    try {
      dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertExceptionContains("already submitted", expected);
    }
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedZones(4);

    // test empty EZ
    final Path emptyZone = new Path("/emptyZone");
    fsWrapper.mkdir(emptyZone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(emptyZone, TEST_KEY, NO_TRASH);

    dfsAdmin.reencryptEncryptionZone(emptyZone, ReencryptAction.START);
    waitForReencryptedZones(5);

    dfsAdmin.reencryptEncryptionZone(emptyZone, ReencryptAction.START);
    waitForReencryptedZones(6);

    // test rename ez and listReencryptionStatus
    final Path renamedZone = new Path("/renamedZone");
    fsWrapper.rename(zone, renamedZone);
    it = dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    zs = it.next();
    assertEquals(renamedZone.toString(), zs.getZoneName());
  }

  @Test
  public void testReencryptOrdering() throws Exception {
    /* Setup dir as follows:
     * /zones/zone/[0-3]
     * /zones/zone/dir/f
     * /zones/zone/f[0-4]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    Path subdir = new Path(zone, "dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);
    for (int i = 0; i < 4; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    for (int i = 0; i < 5; ++i) {
      DFSTestUtil.createFile(fs, new Path(zone, "f" + Integer.toString(i)), len,
          (short) 1, 0xFEED);
    }

    // /zones/zone/f[0-4] should be re-encrypted after /zones/zone/dir/f
    final Path lastReencryptedFile = new Path(subdir, "f");
    final Path notReencrypted = new Path(zone, "f0");
    final FileEncryptionInfo fei = getFileEncryptionInfo(lastReencryptedFile);
    final FileEncryptionInfo feiLast = getFileEncryptionInfo(notReencrypted);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthSubmission(1);
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedFiles(zone.toString(), 5);
    assertKeyVersionChanged(lastReencryptedFile, fei);
    assertKeyVersionEquals(notReencrypted, feiLast);
  }

  @Test
  public void testDeleteDuringReencrypt() throws Exception {
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    // test zone deleted during re-encrypt
    getEzManager().pauseReencryptForTesting();
    getEzManager().resetMetricsForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    fs.delete(zone, true);
    getEzManager().resumeReencryptForTesting();
    waitForTotalZones(0);
    assertNull(getZoneStatus(zone.toString()));
  }

  @Test
  public void testZoneDeleteDuringReencrypt() throws Exception {
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // test zone deleted during re-encrypt's checkpointing
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resetMetricsForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedFiles(zone.toString(), 5);

    fs.delete(zoneParent, true);
    getEzManager().resumeReencryptForTesting();
    waitForTotalZones(0);
    assertNull(getEzManager().getZoneStatus(zone.toString()));

    // verify zone is cleared
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertFalse(it.hasNext());
  }

  @Test
  public void testRestartAfterReencrypt() throws Exception {
    /* Setup dir as follows:
     * /zones
     * /zones/zone
     * /zones/zone/[0-9]
     * /zones/zone/dir
     * /zones/zone/dir/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path(zone, "dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    final Path encFile0 = new Path(zone, "0");
    final Path encFile9 = new Path(zone, "9");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9 = getFileEncryptionInfo(encFile9);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);

    assertKeyVersionChanged(encFile0, fei0);
    assertKeyVersionChanged(encFile9, fei9);

    final FileEncryptionInfo fei0new = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9new = getFileEncryptionInfo(encFile9);
    restartClusterDisableReencrypt();

    assertKeyVersionEquals(encFile0, fei0new);
    assertKeyVersionEquals(encFile9, fei9new);
    assertNull("Re-encrypt queue should be empty after restart",
        getReencryptionStatus().getNextUnprocessedZone());
  }

  @Test
  public void testRestartWithRenames() throws Exception {
    /* Setup dir as follows:
     * /zones
     * /zones/zone
     * /zones/zone/f --> renamed to f1
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, new Path(zone, "f"), len, (short) 1, 0xFEED);
    fsWrapper.rename(new Path(zone, "f"), new Path(zone, "f1"));

    // re-encrypt
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);

    // make sure NN can successfully restart (rename can load ok with
    // re-encrypt since they're in correct order)
    cluster.restartNameNodes();
    cluster.waitActive();

    waitForReencryptedZones(1);
  }

  @Test
  public void testRestartDuringReencrypt() throws Exception {
    /* Setup dir as follows:
     * /zones
     * /zones/zone
     * /zones/zone/dir_empty
     * /zones/zone/dir1/[0-9]
     * /zones/zone/dir1/dir_empty1
     * /zones/zone/dir2
     * /zones/zone/dir2/dir_empty2
     * /zones/zone/dir2/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    fsWrapper
        .mkdir(new Path(zone, "dir_empty"), FsPermission.getDirDefault(), true);
    Path subdir = new Path(zone, "dir2");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    fsWrapper
        .mkdir(new Path(subdir, "dir_empty2"), FsPermission.getDirDefault(),
            true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);
    subdir = new Path(zone, "dir1");
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    fsWrapper
        .mkdir(new Path(subdir, "dir_empty1"), FsPermission.getDirDefault(),
            true);

    final Path encFile0 = new Path(subdir, "0");
    final Path encFile9 = new Path(subdir, "9");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9 = getFileEncryptionInfo(encFile9);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthSubmission(1);
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedFiles(zone.toString(), 5);

    restartClusterDisableReencrypt();

    final Long zoneId = fsn.getFSDirectory().getINode(zone.toString()).getId();
    assertEquals("Re-encrypt should restore to the last checkpoint zone",
        zoneId, getReencryptionStatus().getNextUnprocessedZone());
    assertEquals("Re-encrypt should restore to the last checkpoint file",
        new Path(subdir, "4").toString(),
        getEzManager().getZoneStatus(zone.toString()).getLastCheckpointFile());

    getEzManager().resumeReencryptForTesting();
    waitForReencryptedZones(1);
    assertKeyVersionChanged(encFile0, fei0);
    assertKeyVersionChanged(encFile9, fei9);
    assertNull("Re-encrypt queue should be empty after restart",
        getReencryptionStatus().getNextUnprocessedZone());
    assertEquals(11, getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRestartAfterReencryptAndCheckpoint() throws Exception {
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path(zone, "dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    final Path encFile0 = new Path(zone, "0");
    final Path encFile9 = new Path(zone, "9");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9 = getFileEncryptionInfo(encFile9);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);

    assertKeyVersionChanged(encFile0, fei0);
    assertKeyVersionChanged(encFile9, fei9);

    final FileEncryptionInfo fei0new = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9new = getFileEncryptionInfo(encFile9);
    fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
    fs.saveNamespace();
    fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
    restartClusterDisableReencrypt();

    assertKeyVersionEquals(encFile0, fei0new);
    assertKeyVersionEquals(encFile9, fei9new);
    assertNull("Re-encrypt queue should be empty after restart",
        getReencryptionStatus().getNextUnprocessedZone());
  }

  @Test
  public void testReencryptLoadedFromEdits() throws Exception {
    /*
     * /zones/zone/[0-9]
     * /zones/zone/dir/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path(zone, "dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    final Path encFile0 = new Path(zone, "0");
    final Path encFile9 = new Path(zone, "9");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9 = getFileEncryptionInfo(encFile9);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // disable re-encrypt for testing, and issue a command
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);

    // verify after restart the command is loaded
    restartClusterDisableReencrypt();
    waitForQueuedZones(1);

    // Let the re-encrypt to start running.
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedZones(1);
    assertKeyVersionChanged(encFile0, fei0);
    assertKeyVersionChanged(encFile9, fei9);

    // verify status
    verifyZoneStatus(zone, fei0, 11);
  }

  private void verifyZoneStatus(final Path zone, final FileEncryptionInfo fei,
      final long expectedFiles) throws IOException {
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    final ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    if (fei != null) {
      assertNotEquals(fei.getEzKeyVersionName(), zs.getEzKeyVersionName());
    }
    assertEquals(expectedFiles, zs.getFilesReencrypted());
  }

  @Test
  public void testReencryptLoadedFromFsimage() throws Exception {
    /*
     * /zones/zone/[0-9]
     * /zones/zone/dir/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path(zone, "dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    final Path encFile0 = new Path(zone, "0");
    final Path encFile9 = new Path(zone, "9");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile0);
    final FileEncryptionInfo fei9 = getFileEncryptionInfo(encFile9);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // disable re-encrypt for testing, and issue a command
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
    fs.saveNamespace();
    fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);

    // verify after loading from fsimage the command is loaded
    restartClusterDisableReencrypt();
    waitForQueuedZones(1);

    // Let the re-encrypt to start running.
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedZones(1);
    assertKeyVersionChanged(encFile0, fei0);
    assertKeyVersionChanged(encFile9, fei9);

    // verify status
    verifyZoneStatus(zone, fei0, 11);
  }

  @Test
  public void testReencryptCommandsQueuedOrdering() throws Exception {
    final Path zoneParent = new Path("/zones");
    final String zoneBaseName = zoneParent.toString() + "/zone";
    final int numZones = 10;
    for (int i = 0; i < numZones; ++i) {
      final Path zone = new Path(zoneBaseName + i);
      fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
      dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    }

    // Disable re-encrypt for testing, and issue commands
    getEzManager().pauseReencryptForTesting();
    for (int i = 0; i < numZones; ++i) {
      dfsAdmin.reencryptEncryptionZone(new Path(zoneBaseName + i),
          ReencryptAction.START);
    }
    waitForQueuedZones(numZones);

    // Verify commands are queued in the same order submitted
    ReencryptionStatus rzs = new ReencryptionStatus(getReencryptionStatus());
    for (int i = 0; i < numZones; ++i) {
      Long zoneId = fsn.getFSDirectory().getINode(zoneBaseName + i).getId();
      assertEquals(zoneId, rzs.getNextUnprocessedZone());
      rzs.removeZone(zoneId);
    }

    // Cancel some zones
    Set<Integer> cancelled = new HashSet<>(Arrays.asList(0, 3, 4));
    for (int cancel : cancelled) {
      dfsAdmin.reencryptEncryptionZone(new Path(zoneBaseName + cancel),
          ReencryptAction.CANCEL);
    }

    restartClusterDisableReencrypt();
    waitForQueuedZones(numZones - cancelled.size());
    rzs = new ReencryptionStatus(getReencryptionStatus());
    for (int i = 0; i < numZones; ++i) {
      if (cancelled.contains(i)) {
        continue;
      }
      Long zoneId = fsn.getFSDirectory().getINode(zoneBaseName + i).getId();
      assertEquals(zoneId, rzs.getNextUnprocessedZone());
      rzs.removeZone(zoneId);
    }

    // Verify the same is true after loading from FSImage
    fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
    fs.saveNamespace();
    fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);

    restartClusterDisableReencrypt();
    waitForQueuedZones(numZones - cancelled.size());
    rzs = new ReencryptionStatus(getReencryptionStatus());
    for (int i = 0; i < 10; ++i) {
      if (cancelled.contains(i)) {
        continue;
      }
      Long zoneId = fsn.getFSDirectory().getINode(zoneBaseName + i).getId();
      assertEquals(zoneId, rzs.getNextUnprocessedZone());
      rzs.removeZone(zoneId);
    }
  }

  @Test
  public void testReencryptNestedZones() throws Exception {
    /* Setup dir as follows:
     * / <- EZ
     * /file
     * /dir/dfile
     * /level1  <- nested EZ
     * /level1/fileL1-[0~2]
     * /level1/level2/ <- nested EZ
     * /level1/level2/fileL2-[0~3]
     */
    final int len = 8196;
    final Path zoneRoot = new Path("/");
    final Path zoneL1 = new Path(zoneRoot, "level1");
    final Path zoneL2 = new Path(zoneL1, "level2");
    final Path nonzoneDir = new Path(zoneRoot, "dir");
    dfsAdmin.createEncryptionZone(zoneRoot, TEST_KEY, NO_TRASH);
    DFSTestUtil
        .createFile(fs, new Path(zoneRoot, "file"), len, (short) 1, 0xFEED);
    DFSTestUtil
        .createFile(fs, new Path(nonzoneDir, "dfile"), len, (short) 1, 0xFEED);
    fsWrapper.mkdir(zoneL1, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zoneL1, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 3; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zoneL1, "fileL1-" + i), len, (short) 1,
              0xFEED);
    }
    fsWrapper.mkdir(zoneL2, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zoneL2, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 4; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zoneL2, "fileL2-" + i), len, (short) 1,
              0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Disable re-encrypt, send re-encrypt on '/', verify queue
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zoneRoot, ReencryptAction.START);
    waitForQueuedZones(1);
    ReencryptionStatus rzs = getReencryptionStatus();
    assertEquals(
        (Long) fsn.getFSDirectory().getINode(zoneRoot.toString()).getId(),
        rzs.getNextUnprocessedZone());

    // Resume re-encrypt, verify files re-encrypted
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zoneRoot.toString());
    assertEquals(2, getZoneStatus(zoneRoot.toString()).getFilesReencrypted());

    // Same tests on a child EZ.
    getEzManager().resetMetricsForTesting();
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zoneL1, ReencryptAction.START);
    waitForQueuedZones(1);
    rzs = getReencryptionStatus();
    assertEquals(
        (Long) fsn.getFSDirectory().getINode(zoneL1.toString()).getId(),
        rzs.getNextUnprocessedZone());

    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zoneL1.toString());
    assertEquals(3, getZoneStatus(zoneL1.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceCreateHandler() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~9]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    int expected = 10;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthSubmission(1);
    // Resume the re-encrypt thread
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);

    /* creates the following:
     * /dir/file8[0~5]
     * /dir/dirsub/file[10-14]
     * /dir/sub/file[15-19]
     */
    for (int i = 0; i < 6; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file8" + i), len, (short) 1, 0xFEED);
    }
    // we don't care newly created files since they should already use new edek.
    // so naturally processes the listing from last checkpoint
    final Path subdir = new Path(zone, "dirsub");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    for (int i = 10; i < 15; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, "file" + i), len, (short) 1, 0xFEED);
    }
    // the above are created before checkpoint position, so not re-encrypted.
    final Path sub = new Path(zone, "sub");
    fsWrapper.mkdir(sub, FsPermission.getDirDefault(), true);
    for (int i = 15; i < 20; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(sub, "file" + i), len, (short) 1, 0xFEED);
    }

    // resume re-encrypt thread which was paused after first checkpoint
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceDeleteHandler() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~9]
     * /dir/subdir/file[10-14]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    int expected = 15;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }
    final Path subdir = new Path(zone, "subdir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    for (int i = 10; i < 15; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // proceed to first checkpoint (5 files), delete files/subdir, then resume
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);

    fsWrapper.delete(new Path(zone, "file5"), true);
    fsWrapper.delete(new Path(zone, "file8"), true);
    expected -= 2;
    fsWrapper.delete(subdir, true);
    expected -= 5;

    // resume re-encrypt thread which was paused after first checkpoint
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceDeleteUpdater() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~9]
     * /dir/subdir/file[10-14]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    int expected = 15;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }
    final Path subdir = new Path(zone, "subdir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    for (int i = 10; i < 15; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // proceed to first checkpoint (5 files), delete files/subdir, then resume
    getEzManager().pauseForTestingAfterNthCheckpoint(zone.toString(), 1);
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();

    waitForReencryptedFiles(zone.toString(), 5);
    getEzManager().resumeReencryptForTesting();

    // give handler thread some time to process the files before deletion.
    Thread.sleep(3000);
    fsWrapper.delete(new Path(zone, "file5"), true);
    fsWrapper.delete(new Path(zone, "file8"), true);
    expected -= 2;
    fsWrapper.delete(subdir, true);
    expected -= 5;

    // resume updater thread which was paused after first checkpoint, verify
    // deleted files are skipped.
    getEzManager().resumeReencryptUpdaterForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceDeleteCurrentDirHandler() throws Exception {
    /* Setup dir as follows:
     * /dir/subdir/file[0~9]
     * /dir/subdir2/file[10-14]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    final Path subdir = new Path(zone, "subdir");
    int expected = 15;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, "file" + i), len, (short) 1, 0xFEED);
    }
    final Path subdir2 = new Path(zone, "subdir2");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    for (int i = 10; i < 15; ++i) {
      DFSTestUtil.createFile(fs, new Path(subdir2, "file" + i), len, (short) 1,
          0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // proceed to first checkpoint (5 files), delete subdir, then resume
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);

    fsWrapper.delete(subdir, true);
    expected -= 5;

    // resume re-encrypt thread which was paused after first checkpoint
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceDeleteCurrentDirUpdater() throws Exception {
    /* Setup dir as follows:
     * /dir/subdir/file[0~9]
     * /dir/subdir2/file[10-14]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    final Path subdir = new Path(zone, "subdir");
    int expected = 15;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, "file" + i), len, (short) 1, 0xFEED);
    }
    final Path subdir2 = new Path(zone, "subdir2");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    for (int i = 10; i < 15; ++i) {
      DFSTestUtil.createFile(fs, new Path(subdir2, "file" + i), len, (short) 1,
          0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // proceed to first checkpoint (5 files), delete subdir, then resume
    getEzManager().pauseForTestingAfterNthCheckpoint(zone.toString(), 1);
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();

    waitForReencryptedFiles(zone.toString(), 5);
    getEzManager().resumeReencryptForTesting();

    // give handler thread some time to process the files before deletion.
    Thread.sleep(3000);
    fsWrapper.delete(subdir, true);
    expected -= 5;

    // resume updater thread which was paused after first checkpoint, verify
    // deleted files are skipped.
    getEzManager().resumeReencryptUpdaterForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceDeleteZoneHandler() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~10]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 11; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // let both handler and updater pause, then delete zone.
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().pauseForTestingAfterNthCheckpoint(zone.toString(), 1);
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();

    Thread.sleep(3000);
    EncryptionZoneManager ezm = getEzManager();
    ReencryptionHandler handler = (ReencryptionHandler) Whitebox
        .getInternalState(ezm, "reencryptionHandler");
    Map<Long, ZoneSubmissionTracker> tasks =
        (Map<Long, ZoneSubmissionTracker>) Whitebox
            .getInternalState(handler, "submissions");
    List<Future> futures = new LinkedList<>();
    for (ZoneSubmissionTracker zst : tasks.values()) {
      for (Future f : zst.getTasks()) {
        futures.add(f);
      }
    }
    fsWrapper.delete(zone, true);
    getEzManager().resumeReencryptForTesting();

    // verify no running tasks
    for (Future f : futures) {
      assertTrue(f.isDone());
    }

    waitForTotalZones(0);
  }

  @Test
  public void testRaceDeleteCreateHandler() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~9]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    int expected = 10;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthSubmission(1);
    // Resume the re-encrypt thread
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);

    final Path recreated = new Path(zone, "file9");
    fsWrapper.delete(recreated, true);
    DFSTestUtil.createFile(fs, recreated, len, (short) 2, 0xFEED);
    expected -= 1; // newly created files use new edek, no need to re-encrypt

    // resume re-encrypt thread which was paused after first checkpoint
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testRaceDeleteCreateUpdater() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~9]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    int expected = 10;
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthCheckpoint(zone.toString(), 1);
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);
    getEzManager().resumeReencryptForTesting();

    // give handler thread some time to process the files before deletion.
    Thread.sleep(3000);
    final Path recreated = new Path(zone, "file9");
    final FileEncryptionInfo feiOrig = getFileEncryptionInfo(recreated);
    final String contentOrig = DFSTestUtil.readFile(fs, recreated);
    fsWrapper.delete(recreated, true);
    DFSTestUtil.createFile(fs, recreated, len, (short) 2, 0xFEED);
    expected -= 1;

    // resume updater thread which was paused after first checkpoint
    getEzManager().resumeReencryptUpdaterForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(expected,
        getZoneStatus(zone.toString()).getFilesReencrypted());

    // verify new file is using it's own edeks, with new keyversions,
    // and can be decrypted correctly.
    assertKeyVersionChanged(recreated, feiOrig);
    final String content = DFSTestUtil.readFile(fs, recreated);
    assertEquals(contentOrig, content);
  }

  // TODO: update test once HDFS-11203 is implemented.
  @Test
  public void testReencryptRaceRename() throws Exception {
    /* Setup dir as follows:
     * /dir/file[0~9]
     * /dir/subdir/file[10-14]
     */
    final int len = 8196;
    final Path zone = new Path("/dir");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, "file" + i), len, (short) 1, 0xFEED);
    }
    final Path subdir = new Path(zone, "subdir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    for (int i = 10; i < 15; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(subdir, "file" + i), len, (short) 1, 0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // Issue the command re-encrypt and pause it
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthSubmission(1);
    // Resume the re-encrypt thread
    getEzManager().resumeReencryptForTesting();
    waitForReencryptedFiles(zone.toString(), 5);

    try {
      fsWrapper.rename(new Path(zone, "file8"), new Path(zone, "file08"));
      fail("rename a file in an EZ should be disabled");
    } catch (IOException e) {
      assertExceptionContains("under re-encryption", e);
    }

    // resume handler and pause updater, test again.
    getEzManager().pauseReencryptUpdaterForTesting();
    getEzManager().resumeReencryptForTesting();
    try {
      fsWrapper.rename(new Path(zone, "file8"), new Path(zone, "file08"));
      fail("rename a file in an EZ should be disabled");
    } catch (IOException e) {
      assertExceptionContains("under re-encryption", e);
    }
  }

  @Test
  public void testReencryptSnapshots() throws Exception {
    /* Setup test dir:
     * /zones/zone/[0-9]
     * /dir/f
     *
     * /zones/zone is snapshottable, and rename file 5 to 5new,
      * 6 to 6new then delete (so the file is only referred from a snapshot).
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.allowSnapshot(zone);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path("/dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);
    // create a snapshot and rename a file, so INodeReference is created.
    final Path zoneSnap = fs.createSnapshot(zone);
    fsWrapper.rename(new Path(zone, "5"), new Path(zone, "5new"));
    fsWrapper.rename(new Path(zone, "6"), new Path(zone, "6new"));
    fsWrapper.delete(new Path(zone, "6new"), true);

    // test re-encrypt on snapshot dir
    final Path encFile1 = new Path(zone, "0");
    final FileEncryptionInfo fei0 = getFileEncryptionInfo(encFile1);
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    try {
      dfsAdmin.reencryptEncryptionZone(zoneSnap, ReencryptAction.START);
      fail("Reencrypt command on snapshot path should fail.");
    } catch (RemoteException expected) {
      LOG.info("Expected exception", expected);
      assertTrue(expected
          .unwrapRemoteException() instanceof SnapshotAccessControlException);
    }
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);
    waitForReencryptedFiles(zone.toString(), 9);
    assertKeyVersionChanged(encFile1, fei0);
  }

  private void restartClusterDisableReencrypt() throws Exception {
    cluster.restartNameNode(false);
    fsn = cluster.getNamesystem();
    getEzManager().pauseReencryptForTesting();
    cluster.waitActive();
  }

  private void waitForReencryptedZones(final int expected)
      throws TimeoutException, InterruptedException {
    LOG.info("Waiting for re-encrypted zones to be {}", expected);
    try {
      GenericTestUtils.waitFor(new Supplier<Boolean>() {
        @Override
        public Boolean get() {
          return getReencryptionStatus().getNumZonesReencrypted() == expected;
        }
      }, 100, 10000);
    } finally {
      LOG.info("Re-encrypted zones = {} ",
          getReencryptionStatus().getNumZonesReencrypted());
    }
  }

  private void waitForQueuedZones(final int expected)
      throws TimeoutException, InterruptedException {
    LOG.info("Waiting for queued zones for re-encryption to be {}", expected);
    GenericTestUtils.waitFor(new Supplier<Boolean>() {
      @Override
      public Boolean get() {
        return getReencryptionStatus().zonesQueued() == expected;
      }
    }, 100, 10000);
  }

  private void waitForTotalZones(final int expected)
      throws TimeoutException, InterruptedException {
    LOG.info("Waiting for queued zones for re-encryption to be {}", expected);
    GenericTestUtils.waitFor(new Supplier<Boolean>() {
      @Override
      public Boolean get() {
        return getReencryptionStatus().zonesTotal() == expected;
      }
    }, 100, 10000);
  }

  private void waitForZoneCompletes(final String zone)
      throws TimeoutException, InterruptedException {
    LOG.info("Waiting for re-encryption zone {} to complete.", zone);
    GenericTestUtils.waitFor(new Supplier<Boolean>() {
      @Override
      public Boolean get() {
        try {
          return getZoneStatus(zone).getState()
              == ZoneReencryptionStatus.State.Completed;
        } catch (Exception ex) {
          LOG.error("Exception caught", ex);
          return false;
        }
      }
    }, 100, 10000);
  }

  private EncryptionZoneManager getEzManager() {
    return fsn.getFSDirectory().ezManager;
  }

  private ReencryptionStatus getReencryptionStatus() {
    return getEzManager().getReencryptionStatus();
  }

  private ZoneReencryptionStatus getZoneStatus(final String zone)
      throws IOException {
    return getEzManager().getZoneStatus(zone);
  }

  private void waitForReencryptedFiles(final String zone, final int expected)
      throws TimeoutException, InterruptedException {
    LOG.info("Waiting for total re-encrypted file count to be {}", expected);
    GenericTestUtils.waitFor(new Supplier<Boolean>() {
      @Override
      public Boolean get() {
        try {
          return getZoneStatus(zone).getFilesReencrypted() == expected;
        } catch (IOException e) {
          return false;
        }
      }
    }, 100, 10000);
  }

  private void assertKeyVersionChanged(final Path file,
      final FileEncryptionInfo original) throws Exception {
    final FileEncryptionInfo actual = getFileEncryptionInfo(file);
    assertNotEquals("KeyVersion should be different",
        original.getEzKeyVersionName(), actual.getEzKeyVersionName());
  }

  private void assertKeyVersionEquals(final Path file,
      final FileEncryptionInfo expected) throws Exception {
    final FileEncryptionInfo actual = getFileEncryptionInfo(file);
    assertEquals("KeyVersion should be the same",
        expected.getEzKeyVersionName(), actual.getEzKeyVersionName());
  }

  @Test
  public void testReencryptCancel() throws Exception {
    /* Setup test dir:
     * /zones/zone/[0-9]
     * /dir/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path("/dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // disable, test basic
    getEzManager().pauseReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForQueuedZones(1);

    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.CANCEL);
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(0, getZoneStatus(zone.toString()).getFilesReencrypted());

    // test same command resubmission
    try {
      dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.CANCEL);
    } catch (RemoteException expected) {
      assertExceptionContains("not under re-encryption", expected);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // test cancelling half-way
    getEzManager().pauseForTestingAfterNthSubmission(1);
    getEzManager().resumeReencryptForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedFiles(zone.toString(), 5);
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.CANCEL);
    getEzManager().resumeReencryptForTesting();
    waitForZoneCompletes(zone.toString());
    assertEquals(5, getZoneStatus(zone.toString()).getFilesReencrypted());
    assertNull(
        getEzManager().getZoneStatus(zone.toString()).getLastCheckpointFile());
    assertNull(getReencryptionStatus().getNextUnprocessedZone());

    // test cancelling non-EZ dir
    try {
      dfsAdmin.reencryptEncryptionZone(subdir, ReencryptAction.CANCEL);
      fail("Re-encrypting non-EZ should fail");
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertExceptionContains("not the root of an encryption zone", expected);
    }

    // test cancelling non-existing dir
    try {
      dfsAdmin.reencryptEncryptionZone(new Path(zone, "notexist"),
          ReencryptAction.CANCEL);
      fail("Re-encrypting non-existing dir should fail");
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertTrue(
          expected.unwrapRemoteException() instanceof FileNotFoundException);
    }

    // test cancelling directly on a EZ file
    final Path encFile = new Path(zone, "0");
    try {
      dfsAdmin.reencryptEncryptionZone(encFile, ReencryptAction.CANCEL);
      fail("Re-encrypting on a file should fail");
    } catch (RemoteException expected) {
      LOG.info("Expected exception caught.", expected);
      assertExceptionContains("not the root of an encryption zone", expected);
    }

    // final check - should only had 5 files re-encrypted overall.
    assertEquals(5, getZoneStatus(zone.toString()).getFilesReencrypted());
  }

  @Test
  public void testReencryptCancelForUpdater() throws Exception {
    /* Setup test dir:
     * /zones/zone/[0-9]
     * /dir/f
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }
    final Path subdir = new Path("/dir");
    fsWrapper.mkdir(subdir, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, new Path(subdir, "f"), len, (short) 1, 0xFEED);

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // disable, test basic
    getEzManager().pauseReencryptUpdaterForTesting();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    Thread.sleep(3000);

    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.CANCEL);
    getEzManager().resumeReencryptUpdaterForTesting();
    waitForZoneCompletes(zone.toString());
    Thread.sleep(3000);
    assertEquals(0, getZoneStatus(zone.toString()).getFilesReencrypted());

  }

  @Test
  public void testReencryptionWithoutProvider() throws Exception {
    /* Setup test dir:
     * /zones/zone/[0-9]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    // re-encrypt the zone
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);

    // start NN without providers
    cluster.getConfiguration(0)
        .unset(CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH);
    cluster.restartNameNodes();
    cluster.waitActive();

    // test re-encrypt should fail
    try {
      dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
      fail("should not be able to re-encrypt");
    } catch (RemoteException expected) {
      assertExceptionContains("rejected", expected.unwrapRemoteException());
    }
    try {
      dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.CANCEL);
      fail("should not be able to cancel re-encrypt");
    } catch (RemoteException expected) {
      assertExceptionContains("rejected", expected.unwrapRemoteException());
    }

    // test listReencryptionStatus should still work
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    assertEquals(10, zs.getFilesReencrypted());
  }

  @Test
  public void testReencryptionNNSafeMode() throws Exception {
    /* Setup test dir:
     * /zones/zone/[0-9]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();
    // mark pause after first checkpoint (5 files)
    getEzManager().pauseForTestingAfterNthSubmission(1);
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedFiles(zone.toString(), 5);

    fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
    getEzManager().resumeReencryptForTesting();
    for (int i = 0; i < 3; ++i) {
      Thread.sleep(1000);
      RemoteIterator<ZoneReencryptionStatus> it =
          dfsAdmin.listReencryptionStatus();
      assertTrue(it.hasNext());
      ZoneReencryptionStatus zs = it.next();
      assertEquals(zone.toString(), zs.getZoneName());
      assertEquals(0, zs.getCompletionTime());
      assertEquals(5, zs.getFilesReencrypted());
    }

    fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
    waitForReencryptedFiles(zone.toString(), 10);
  }

  @Test
  public void testReencryptionKMSDown() throws Exception {
    class MyInjector extends EncryptionFaultInjector {
      private volatile int exceptionCount = 0;

      MyInjector(int numFailures) {
        exceptionCount = numFailures;
      }

      @Override
      public void reencryptEncryptedKeys() throws IOException {
        if (exceptionCount > 0) {
          --exceptionCount;
          throw new IOException("Injected KMS failure");
        }
      }
    }
    final MyInjector injector = new MyInjector(1);
    EncryptionFaultInjector.instance = injector;
    /* Setup test dir:
     * /zones/zone/[0-9]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    // re-encrypt the zone
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();

    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);
    assertEquals(0, injector.exceptionCount);

    // test listReencryptionStatus should still work
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    assertEquals(5, zs.getFilesReencrypted());
    assertEquals(5, zs.getNumReencryptionFailures());
  }

  @Test
  public void testReencryptionUpdaterFaultOneTask() throws Exception {
    class MyInjector extends EncryptionFaultInjector {
      private volatile int exceptionCount = 0;

      MyInjector(int numFailures) {
        exceptionCount = numFailures;
      }

      @Override
      public void reencryptUpdaterProcessOneTask() throws IOException {
        if (exceptionCount > 0) {
          --exceptionCount;
          throw new IOException("Injected process task failure");
        }
      }
    }
    final MyInjector injector = new MyInjector(1);
    EncryptionFaultInjector.instance = injector;
    /* Setup test dir:
     * /zones/zone/[0-9]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    // re-encrypt the zone
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();

    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);
    assertEquals(0, injector.exceptionCount);

    // test listReencryptionStatus should still work
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    assertEquals(5, zs.getFilesReencrypted());
    assertEquals(1, zs.getNumReencryptionFailures());
  }


  @Test
  public void testReencryptionUpdaterFaultCkpt() throws Exception {
    class MyInjector extends EncryptionFaultInjector {
      private volatile int exceptionCount = 0;

      MyInjector(int numFailures) {
        exceptionCount = numFailures;
      }

      @Override
      public void reencryptUpdaterProcessCheckpoint() throws IOException {
        if (exceptionCount > 0) {
          --exceptionCount;
          throw new IOException("Injected process checkpoint failure");
        }
      }
    }
    final MyInjector injector = new MyInjector(1);
    EncryptionFaultInjector.instance = injector;
    /* Setup test dir:
     * /zones/zone/[0-9]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    // re-encrypt the zone
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();

    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);
    assertEquals(0, injector.exceptionCount);

    // test listReencryptionStatus should still work
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    assertEquals(10, zs.getFilesReencrypted());
    assertEquals(1, zs.getNumReencryptionFailures());
  }

  @Test
  public void testReencryptionUpdaterFaultRecover() throws Exception {
    class MyInjector extends EncryptionFaultInjector {
      private volatile int exceptionCount = 0;

      MyInjector(int oneTask) {
        exceptionCount = oneTask;
      }

      @Override
      public void reencryptUpdaterProcessOneTask() throws IOException {
        if (exceptionCount > 0) {
          --exceptionCount;
          throw new RetriableException("Injected process task failure");
        }
      }
    }
    final MyInjector injector = new MyInjector(10);
    EncryptionFaultInjector.instance = injector;
    /* Setup test dir:
     * /zones/zone/[0-9]
     */
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    for (int i = 0; i < 10; ++i) {
      DFSTestUtil
          .createFile(fs, new Path(zone, Integer.toString(i)), len, (short) 1,
              0xFEED);
    }

    // re-encrypt the zone
    fsn.getProvider().rollNewVersion(TEST_KEY);
    fsn.getProvider().flush();

    final EncryptionZoneManager ezm = getEzManager();
    final ReencryptionHandler handler = (ReencryptionHandler) Whitebox
        .getInternalState(ezm, "reencryptionHandler");
    final ReencryptionUpdater updater = (ReencryptionUpdater) Whitebox
        .getInternalState(handler, "reencryptionUpdater");
    Whitebox.setInternalState(updater, "faultRetryInterval", 50);
    dfsAdmin.reencryptEncryptionZone(zone, ReencryptAction.START);
    waitForReencryptedZones(1);
    assertEquals(0, injector.exceptionCount);

    // test listReencryptionStatus should still work
    RemoteIterator<ZoneReencryptionStatus> it =
        dfsAdmin.listReencryptionStatus();
    assertTrue(it.hasNext());
    ZoneReencryptionStatus zs = it.next();
    assertEquals(zone.toString(), zs.getZoneName());
    assertEquals(ZoneReencryptionStatus.State.Completed, zs.getState());
    assertTrue(zs.getCompletionTime() > 0);
    assertTrue(zs.getCompletionTime() > zs.getSubmissionTime());
    assertEquals(10, zs.getFilesReencrypted());
    assertEquals(0, zs.getNumReencryptionFailures());
  }
}