/**
 * 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;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.RandomAccessFile;
import java.io.StringReader;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.URI;
import java.net.URL;
import java.security.PrivilegedExceptionAction;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.EnumSet;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.crypto.CipherSuite;
import org.apache.hadoop.crypto.CryptoInputStream;
import org.apache.hadoop.crypto.CryptoProtocolVersion;
import org.apache.hadoop.crypto.key.JavaKeyStoreProvider;
import org.apache.hadoop.crypto.key.KeyProvider;
import org.apache.hadoop.crypto.key.KeyProviderFactory;
import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FSTestWrapper;
import org.apache.hadoop.fs.FileContext;
import org.apache.hadoop.fs.FileContextTestWrapper;
import org.apache.hadoop.fs.FileEncryptionInfo;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FileSystemTestHelper;
import org.apache.hadoop.fs.FileSystemTestWrapper;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.fs.FsServerDefaults;
import org.apache.hadoop.fs.FsShell;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RemoteIterator;
import org.apache.hadoop.fs.SafeModeAction;
import org.apache.hadoop.fs.permission.FsAction;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.client.CreateEncryptionZoneFlag;
import org.apache.hadoop.hdfs.client.HdfsAdmin;
import org.apache.hadoop.hdfs.protocol.ClientProtocol;
import org.apache.hadoop.hdfs.protocol.EncryptionZone;
import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport;
import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport.DiffReportEntry;
import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport.DiffType;
import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
import org.apache.hadoop.hdfs.server.namenode.EncryptionFaultInjector;
import org.apache.hadoop.hdfs.server.namenode.EncryptionZoneManager;
import org.apache.hadoop.hdfs.server.namenode.FSImageTestUtil;
import org.apache.hadoop.hdfs.server.namenode.NamenodeFsck;
import org.apache.hadoop.hdfs.tools.CryptoAdmin;
import org.apache.hadoop.hdfs.tools.DFSck;
import org.apache.hadoop.hdfs.tools.offlineImageViewer.PBImageXmlWriter;
import org.apache.hadoop.hdfs.web.WebHdfsConstants;
import org.apache.hadoop.hdfs.web.WebHdfsFileSystem;
import org.apache.hadoop.hdfs.web.WebHdfsTestUtil;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.security.AccessControlException;
import org.apache.hadoop.security.Credentials;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.authorize.AuthorizationException;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.security.token.DelegationTokenIssuer;
import org.apache.hadoop.thirdparty.com.google.common.collect.Lists;
import org.apache.hadoop.util.DataChecksum;
import org.apache.hadoop.util.ToolRunner;
import org.apache.hadoop.crypto.key.KeyProviderDelegationTokenExtension.DelegationTokenExtension;
import org.apache.hadoop.crypto.key.KeyProviderCryptoExtension.CryptoExtension;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.util.XMLUtils;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.Timeout;
import org.mockito.Mockito;

import static org.apache.hadoop.fs.CommonConfigurationKeys.DFS_CLIENT_IGNORE_NAMENODE_DEFAULT_KMS_URI;
import static org.junit.Assert.assertNotNull;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.anyBoolean;
import static org.mockito.ArgumentMatchers.anyLong;
import static org.mockito.ArgumentMatchers.anyShort;
import static org.mockito.Mockito.withSettings;
import static org.mockito.Mockito.anyString;
import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.FS_TRASH_INTERVAL_DEFAULT;
import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.FS_TRASH_INTERVAL_KEY;
import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.IO_FILE_BUFFER_SIZE_DEFAULT;
import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.IO_FILE_BUFFER_SIZE_KEY;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_DEFAULT;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_ENCRYPT_DATA_TRANSFER_DEFAULT;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_ENCRYPT_DATA_TRANSFER_KEY;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_REPLICATION_DEFAULT;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_REPLICATION_KEY;
import static org.apache.hadoop.hdfs.DFSTestUtil.verifyFilesEqual;
import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_BYTES_PER_CHECKSUM_DEFAULT;
import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY;
import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT;
import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_WRITE_PACKET_SIZE_KEY;
import static org.apache.hadoop.test.GenericTestUtils.assertExceptionContains;
import static org.apache.hadoop.test.MetricsAsserts.assertGauge;
import static org.apache.hadoop.test.MetricsAsserts.getMetrics;
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.xml.sax.InputSource;
import org.xml.sax.helpers.DefaultHandler;

import javax.xml.parsers.SAXParser;

public class TestEncryptionZones {
  static final Logger LOG = Logger.getLogger(TestEncryptionZones.class);

  protected Configuration conf;
  private FileSystemTestHelper fsHelper;

  protected MiniDFSCluster cluster;
  protected HdfsAdmin dfsAdmin;
  protected DistributedFileSystem fs;
  private File testRootDir;
  protected final String TEST_KEY = "test_key";
  private static final String NS_METRICS = "FSNamesystem";
  private static final String  AUTHORIZATION_EXCEPTION_MESSAGE =
      "User [root] is not authorized to perform [READ] on key " +
          "with ACL name [key2]!!";

  protected FileSystemTestWrapper fsWrapper;
  protected FileContextTestWrapper fcWrapper;

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

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

  @Rule
  public Timeout globalTimeout = new Timeout(120 * 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);
    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
    cluster.waitActive();
    Logger.getLogger(EncryptionZoneManager.class).setLevel(Level.TRACE);
    fs = cluster.getFileSystem();
    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);
  }
  
  protected 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();
  }

  public void assertNumZones(final int numZones) throws IOException {
    RemoteIterator<EncryptionZone> it = dfsAdmin.listEncryptionZones();
    int count = 0;
    while (it.hasNext()) {
      count++;
      it.next();
    }
    assertEquals("Unexpected number of encryption zones!", numZones, count);
  }

  /**
   * Checks that an encryption zone with the specified keyName and path (if not
   * null) is present.
   *
   * @throws IOException if a matching zone could not be found
   */
  public void assertZonePresent(String keyName, String path) throws IOException {
    final RemoteIterator<EncryptionZone> it = dfsAdmin.listEncryptionZones();
    boolean match = false;
    while (it.hasNext()) {
      EncryptionZone zone = it.next();
      boolean matchKey = (keyName == null);
      boolean matchPath = (path == null);
      if (keyName != null && zone.getKeyName().equals(keyName)) {
        matchKey = true;
      }
      if (path != null && zone.getPath().equals(path)) {
        matchPath = true;
      }
      if (matchKey && matchPath) {
        match = true;
        break;
      }
    }
    assertTrue("Did not find expected encryption zone with keyName " + keyName +
            " path " + path, match
    );
  }

  /**
   * Make sure hdfs crypto -createZone command creates a trash directory
   * with sticky bits.
   * @throws Exception
   */
  @Test
  public void testTrashStickyBit() throws Exception {
    // create an EZ /zones/zone1, make it world writable.
    final Path zoneParent = new Path("/zones");
    final Path zone1 = new Path(zoneParent, "zone1");
    CryptoAdmin cryptoAdmin = new CryptoAdmin(conf);
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    fsWrapper.setPermission(zone1,
        new FsPermission(FsAction.ALL, FsAction.ALL, FsAction.ALL));
    String[] cryptoArgv = new String[]{"-createZone", "-keyName", TEST_KEY,
        "-path", zone1.toUri().getPath()};
    cryptoAdmin.run(cryptoArgv);

    // create a file in EZ
    final Path ezfile1 = new Path(zone1, "file1");
    // Create the encrypted file in zone1
    final int len = 8192;
    DFSTestUtil.createFile(fs, ezfile1, len, (short) 1, 0xFEED);

    // enable trash, delete /zones/zone1/file1,
    // which moves the file to
    // /zones/zone1/.Trash/$SUPERUSER/Current/zones/zone1/file1
    Configuration clientConf = new Configuration(conf);
    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
    final FsShell shell = new FsShell(clientConf);
    String[] argv = new String[]{"-rm", ezfile1.toString()};
    int res = ToolRunner.run(shell, argv);
    assertEquals("Can't remove a file in EZ as superuser", 0, res);

    final Path trashDir = new Path(zone1, FileSystem.TRASH_PREFIX);
    assertTrue(fsWrapper.exists(trashDir));
    FileStatus trashFileStatus = fsWrapper.getFileStatus(trashDir);
    assertTrue(trashFileStatus.getPermission().getStickyBit());

    // create a non-privileged user
    final UserGroupInformation user = UserGroupInformation.
        createUserForTesting("user", new String[] { "mygroup" });

    user.doAs(new PrivilegedExceptionAction<Object>() {
      @Override
      public Object run() throws Exception {
        final Path ezfile2 = new Path(zone1, "file2");
        final int len = 8192;
        // create a file /zones/zone1/file2 in EZ
        // this file is owned by user:mygroup
        FileSystem fs2 = FileSystem.get(cluster.getConfiguration(0));
        DFSTestUtil.createFile(fs2, ezfile2, len, (short) 1, 0xFEED);
        // delete /zones/zone1/file2,
        // which moves the file to
        // /zones/zone1/.Trash/user/Current/zones/zone1/file2
        String[] argv = new String[]{"-rm", ezfile2.toString()};
        int res = ToolRunner.run(shell, argv);
        assertEquals("Can't remove a file in EZ as user:mygroup", 0, res);
        return null;
      }
    });
  }

  /**
   * Tests encrypted files with same original content placed in two different
   * EZ are not same in encrypted form.
   */
  @Test
  public void testEncryptionZonesDictCp() throws Exception {
    final String testkey1 = "testkey1";
    final String testkey2 = "testkey2";
    DFSTestUtil.createKey(testkey1, cluster, conf);
    DFSTestUtil.createKey(testkey2, cluster, conf);

    final int len = 8196;
    final Path zone1 = new Path("/zone1");
    final Path zone1File = new Path(zone1, "file");
    final Path raw1File = new Path("/.reserved/raw/zone1/file");

    final Path zone2 = new Path("/zone2");
    final Path zone2File = new Path(zone2, "file");
    final Path raw2File = new Path(zone2, "/.reserved/raw/zone2/file");

    // 1. Create two encrypted zones
    fs.mkdirs(zone1, new FsPermission(700));
    dfsAdmin.createEncryptionZone(zone1, testkey1, NO_TRASH);

    fs.mkdirs(zone2, new FsPermission(700));
    dfsAdmin.createEncryptionZone(zone2, testkey2, NO_TRASH);

    // 2. Create a file in one of the zones
    DFSTestUtil.createFile(fs, zone1File, len, (short) 1, 0xFEED);
    // 3. Copy it to the other zone through /.raw/reserved
    FileUtil.copy(fs, raw1File, fs, raw2File, false, conf);
    Map<String, byte[]> attrs = fs.getXAttrs(raw1File);
    if (attrs != null) {
      for (Map.Entry<String, byte[]> entry : attrs.entrySet()) {
        String xattrName = entry.getKey();

        try {
          fs.setXAttr(raw2File, xattrName, entry.getValue());
          fail("Exception should be thrown while setting: " +
                  xattrName + " on file:" + raw2File);
        } catch (RemoteException e) {
          Assert.assertEquals(e.getClassName(),
                  IllegalArgumentException.class.getCanonicalName());
          Assert.assertTrue(e.getMessage().
                  contains("does not belong to the key"));
        }
      }
    }

    assertEquals("File can be created on the root encryption zone " +
            "with correct length", len, fs.getFileStatus(zone1File).getLen());
    assertTrue("/zone1 dir is encrypted",
            fs.getFileStatus(zone1).isEncrypted());
    assertTrue("File is encrypted", fs.getFileStatus(zone1File).isEncrypted());

    assertTrue("/zone2 dir is encrypted",
            fs.getFileStatus(zone2).isEncrypted());
    assertTrue("File is encrypted", fs.getFileStatus(zone2File).isEncrypted());

    // 4. Now the decrypted contents of the files should be different.
    DFSTestUtil.verifyFilesNotEqual(fs, zone1File, zone2File, len);

    // 5. Encrypted contents of the files should be same.
    DFSTestUtil.verifyFilesEqual(fs, raw1File, raw2File, len);
  }

  /**
   * Make sure hdfs crypto -provisionTrash command creates a trash directory
   * with sticky bits.
   * @throws Exception
   */
  @Test
  public void testProvisionTrash() throws Exception {
    // create an EZ /zones/zone1
    final Path zoneParent = new Path("/zones");
    final Path zone1 = new Path(zoneParent, "zone1");
    CryptoAdmin cryptoAdmin = new CryptoAdmin(conf);
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    String[] cryptoArgv = new String[]{"-createZone", "-keyName", TEST_KEY,
        "-path", zone1.toUri().getPath()};
    cryptoAdmin.run(cryptoArgv);

    // remove the trash directory
    Configuration clientConf = new Configuration(conf);
    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
    final FsShell shell = new FsShell(clientConf);
    final Path trashDir = new Path(zone1, FileSystem.TRASH_PREFIX);
    String[] argv = new String[]{"-rmdir", trashDir.toUri().getPath()};
    int res = ToolRunner.run(shell, argv);
    assertEquals("Unable to delete trash directory.", 0, res);
    assertFalse(fsWrapper.exists(trashDir));

    // execute -provisionTrash command option and make sure the trash
    // directory has sticky bit.
    String[] provisionTrashArgv = new String[]{"-provisionTrash", "-path",
        zone1.toUri().getPath()};
    cryptoAdmin.run(provisionTrashArgv);

    assertTrue(fsWrapper.exists(trashDir));
    FileStatus trashFileStatus = fsWrapper.getFileStatus(trashDir);
    assertTrue(trashFileStatus.getPermission().getStickyBit());
  }

  // CHECKSTYLE:OFF:MethodLengthCheck
  @Test
  public void testBasicOperations() throws Exception {

    assertNotNull("key provider is not present", dfsAdmin.getKeyProvider());
    int numZones = 0;
    /* Number of EZs should be 0 if no EZ is created */
    assertEquals("Unexpected number of encryption zones!", numZones,
        cluster.getNamesystem().getNumEncryptionZones());
    /* Test failure of create EZ on a directory that doesn't exist. */
    final Path zoneParent = new Path("/zones");
    final Path zone1 = new Path(zoneParent, "zone1");

    try {
      dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
      fail("expected /test doesn't exist");
    } catch (IOException e) {
      assertExceptionContains("cannot find", e);
    }

    /* Normal creation of an EZ */
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
    assertNumZones(++numZones);
    assertZonePresent(null, zone1.toString());

    /* Test failure of create EZ on a directory which is already an EZ. */
    try {
      dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
    } catch (IOException e) {
      assertExceptionContains("is already an encryption zone", e);
    }

    /* create EZ on parent of an EZ should fail */
    try {
      dfsAdmin.createEncryptionZone(zoneParent, TEST_KEY, NO_TRASH);
      fail("EZ over an EZ");
    } catch (IOException e) {
      assertExceptionContains("encryption zone for a non-empty directory", e);
    }

    /* create EZ on a folder with a folder fails */
    final Path notEmpty = new Path("/notEmpty");
    final Path notEmptyChild = new Path(notEmpty, "child");
    fsWrapper.mkdir(notEmptyChild, FsPermission.getDirDefault(), true);
    try {
      dfsAdmin.createEncryptionZone(notEmpty, TEST_KEY, NO_TRASH);
      fail("Created EZ on an non-empty directory with folder");
    } catch (IOException e) {
      assertExceptionContains("create an encryption zone", e);
    }
    fsWrapper.delete(notEmptyChild, false);

    /* create EZ on a folder with a file fails */
    fsWrapper.createFile(notEmptyChild);
    try {
      dfsAdmin.createEncryptionZone(notEmpty, TEST_KEY, NO_TRASH);
      fail("Created EZ on an non-empty directory with file");
    } catch (IOException e) {
      assertExceptionContains("create an encryption zone", e);
    }

    /* Test failure of create EZ on a file. */
    try {
      dfsAdmin.createEncryptionZone(notEmptyChild, TEST_KEY, NO_TRASH);
      fail("Created EZ on a file");
    } catch (IOException e) {
      assertExceptionContains("create an encryption zone for a file.", e);
    }

    /* Test failure of creating an EZ passing a key that doesn't exist. */
    final Path zone2 = new Path("/zone2");
    fsWrapper.mkdir(zone2, FsPermission.getDirDefault(), false);
    final String myKeyName = "mykeyname";
    try {
      dfsAdmin.createEncryptionZone(zone2, myKeyName, NO_TRASH);
      fail("expected key doesn't exist");
    } catch (IOException e) {
      assertExceptionContains("doesn't exist.", e);
    }

    /* Test failure of empty and null key name */
    try {
      dfsAdmin.createEncryptionZone(zone2, "", NO_TRASH);
      fail("created a zone with empty key name");
    } catch (IOException e) {
      assertExceptionContains("Must specify a key name when creating", e);
    }
    try {
      dfsAdmin.createEncryptionZone(zone2, null, NO_TRASH);
      fail("created a zone with null key name");
    } catch (IOException e) {
      assertExceptionContains("Must specify a key name when creating", e);
    }

    assertNumZones(1);

    /* Test success of creating an EZ when they key exists. */
    DFSTestUtil.createKey(myKeyName, cluster, conf);
    dfsAdmin.createEncryptionZone(zone2, myKeyName, NO_TRASH);
    assertNumZones(++numZones);
    assertZonePresent(myKeyName, zone2.toString());
    /* Test failure of create encryption zones as a non super user. */
    final UserGroupInformation user = UserGroupInformation.
        createUserForTesting("user", new String[] { "mygroup" });
    final Path nonSuper = new Path("/nonSuper");
    fsWrapper.mkdir(nonSuper, FsPermission.getDirDefault(), false);

    user.doAs(new PrivilegedExceptionAction<Object>() {
      @Override
      public Object run() throws Exception {
        final HdfsAdmin userAdmin =
            new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
        try {
          userAdmin.createEncryptionZone(nonSuper, TEST_KEY, NO_TRASH);
          fail("createEncryptionZone is superuser-only operation");
        } catch (AccessControlException e) {
          assertExceptionContains("Superuser privilege is required", e);
        }
        return null;
      }
    });

    // Test success of creating an encryption zone a few levels down.
    Path deepZone = new Path("/d/e/e/p/zone");
    fsWrapper.mkdir(deepZone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(deepZone, TEST_KEY, NO_TRASH);
    assertNumZones(++numZones);
    assertZonePresent(null, deepZone.toString());

    // Create and list some zones to test batching of listEZ
    for (int i=1; i<6; i++) {
      final Path zonePath = new Path("/listZone" + i);
      fsWrapper.mkdir(zonePath, FsPermission.getDirDefault(), false);
      dfsAdmin.createEncryptionZone(zonePath, TEST_KEY, NO_TRASH);
      numZones++;
      assertNumZones(numZones);
      assertZonePresent(null, zonePath.toString());
    }

    fs.setSafeMode(SafeModeAction.ENTER);
    fs.saveNamespace();
    fs.setSafeMode(SafeModeAction.LEAVE);
    cluster.restartNameNode(true);
    assertNumZones(numZones);
    assertEquals("Unexpected number of encryption zones!", numZones, cluster
        .getNamesystem().getNumEncryptionZones());
    assertGauge("NumEncryptionZones", numZones, getMetrics(NS_METRICS));
    assertZonePresent(null, zone1.toString());

    // Verify newly added ez is present after restarting the NameNode
    // without persisting the namespace.
    Path nonpersistZone = new Path("/nonpersistZone");
    fsWrapper.mkdir(nonpersistZone, FsPermission.getDirDefault(), false);
    dfsAdmin.createEncryptionZone(nonpersistZone, TEST_KEY, NO_TRASH);
    numZones++;
    cluster.restartNameNode(true);
    assertNumZones(numZones);
    assertZonePresent(null, nonpersistZone.toString());
  }
  // CHECKSTYLE:ON:MethodLengthCheck

  @Test
  public void testBasicOperationsRootDir() throws Exception {
    int numZones = 0;
    final Path rootDir = new Path("/");
    final Path zone1 = new Path(rootDir, "zone1");

    /* Normal creation of an EZ on rootDir */
    dfsAdmin.createEncryptionZone(rootDir, TEST_KEY, NO_TRASH);
    assertNumZones(++numZones);
    assertZonePresent(null, rootDir.toString());

    // Verify rootDir ez is present after restarting the NameNode
    // and saving/loading from fsimage.
    fs.setSafeMode(SafeModeAction.ENTER);
    fs.saveNamespace();
    fs.setSafeMode(SafeModeAction.LEAVE);
    cluster.restartNameNode(true);
    assertNumZones(numZones);
    assertZonePresent(null, rootDir.toString());
  }

  @Test
  public void testEZwithFullyQualifiedPath() throws Exception {
    /* Test failure of create EZ on a directory that doesn't exist. */
    final Path zoneParent = new Path("/zones");
    final Path zone1 = new Path(zoneParent, "zone1");
    final Path zone1FQP = new Path(cluster.getURI().toString(), zone1);
    final Path zone2 = new Path(zoneParent, "zone2");
    final Path zone2FQP = new Path(cluster.getURI().toString(), zone2);

    int numZones = 0;
    EnumSet<CreateEncryptionZoneFlag> withTrash = EnumSet
        .of(CreateEncryptionZoneFlag.PROVISION_TRASH);

    // Create EZ with Trash using FQP
    fsWrapper.mkdir(zone1FQP, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone1FQP, TEST_KEY, withTrash);
    assertNumZones(++numZones);
    assertZonePresent(TEST_KEY, zone1.toString());
    // Check that zone1 contains a .Trash directory
    final Path zone1Trash = new Path(zone1, fs.TRASH_PREFIX);
    assertTrue("CreateEncryptionZone with trash enabled should create a " +
        ".Trash directory in the EZ", fs.exists(zone1Trash));

    // getEncryptionZoneForPath for FQP should return the path component
    EncryptionZone ezForZone1 = dfsAdmin.getEncryptionZoneForPath(zone1FQP);
    assertTrue("getEncryptionZoneForPath for fully qualified path should " +
        "return the path component",
        ezForZone1.getPath().equals(zone1.toString()));

    // Create EZ without Trash
    fsWrapper.mkdir(zone2FQP, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone2FQP, TEST_KEY, NO_TRASH);
    assertNumZones(++numZones);
    assertZonePresent(TEST_KEY, zone2.toString());

    // Provision Trash on zone2 using FQP
    dfsAdmin.provisionEncryptionZoneTrash(zone2FQP);
    EncryptionZone ezForZone2 = dfsAdmin.getEncryptionZoneForPath(zone2FQP);
    Path ezTrashForZone2 = new Path(ezForZone2.getPath(),
        FileSystem.TRASH_PREFIX);
    assertTrue("provisionEZTrash with fully qualified path should create " +
        "trash directory ", fsWrapper.exists(ezTrashForZone2));
  }

  /**
   * Test listing encryption zones as a non super user.
   */
  @Test
  public void testListEncryptionZonesAsNonSuperUser() throws Exception {

    final UserGroupInformation user = UserGroupInformation.
        createUserForTesting("user", new String[] { "mygroup" });

    final Path testRoot = new Path("/tmp/TestEncryptionZones");
    final Path superPath = new Path(testRoot, "superuseronly");
    final Path allPath = new Path(testRoot, "accessall");

    fsWrapper.mkdir(superPath, new FsPermission((short) 0700), true);
    dfsAdmin.createEncryptionZone(superPath, TEST_KEY, NO_TRASH);

    fsWrapper.mkdir(allPath, new FsPermission((short) 0707), true);
    dfsAdmin.createEncryptionZone(allPath, TEST_KEY, NO_TRASH);

    user.doAs(new PrivilegedExceptionAction<Object>() {
      @Override
      public Object run() throws Exception {
        final HdfsAdmin userAdmin =
            new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
        try {
          userAdmin.listEncryptionZones();
        } catch (AccessControlException e) {
          assertExceptionContains("Superuser privilege is required", e);
        }
        return null;
      }
    });
  }

  /**
   * Test getEncryptionZoneForPath as a non super user.
   */
  @Test
  public void testGetEZAsNonSuperUser() throws Exception {

    final UserGroupInformation user = UserGroupInformation.
            createUserForTesting("user", new String[] { "mygroup" });

    final Path testRoot = new Path("/tmp/TestEncryptionZones");
    final Path superPath = new Path(testRoot, "superuseronly");
    final Path superPathFile = new Path(superPath, "file1");
    final Path allPath = new Path(testRoot, "accessall");
    final Path allPathFile = new Path(allPath, "file1");
    final Path nonEZDir = new Path(testRoot, "nonEZDir");
    final Path nonEZFile = new Path(nonEZDir, "file1");
    final Path nonexistent = new Path("/nonexistent");
    final int len = 8192;

    fsWrapper.mkdir(testRoot, new FsPermission((short) 0777), true);
    fsWrapper.mkdir(superPath, new FsPermission((short) 0700), false);
    fsWrapper.mkdir(allPath, new FsPermission((short) 0777), false);
    fsWrapper.mkdir(nonEZDir, new FsPermission((short) 0777), false);
    dfsAdmin.createEncryptionZone(superPath, TEST_KEY, NO_TRASH);
    dfsAdmin.createEncryptionZone(allPath, TEST_KEY, NO_TRASH);
    dfsAdmin.allowSnapshot(new Path("/"));
    final Path newSnap = fs.createSnapshot(new Path("/"));
    DFSTestUtil.createFile(fs, superPathFile, len, (short) 1, 0xFEED);
    DFSTestUtil.createFile(fs, allPathFile, len, (short) 1, 0xFEED);
    DFSTestUtil.createFile(fs, nonEZFile, len, (short) 1, 0xFEED);

    user.doAs(new PrivilegedExceptionAction<Object>() {
      @Override
      public Object run() throws Exception {
        final HdfsAdmin userAdmin =
            new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);

        // Check null arg
        try {
          userAdmin.getEncryptionZoneForPath(null);
          fail("should have thrown NPE");
        } catch (NullPointerException e) {
          /*
           * IWBNI we could use assertExceptionContains, but the NPE that is
           * thrown has no message text.
           */
        }

        // Check operation with accessible paths
        assertEquals("expected ez path", allPath.toString(),
            userAdmin.getEncryptionZoneForPath(allPath).getPath().
            toString());
        assertEquals("expected ez path", allPath.toString(),
            userAdmin.getEncryptionZoneForPath(allPathFile).getPath().
            toString());

        // Check operation with inaccessible (lack of permissions) path
        try {
          userAdmin.getEncryptionZoneForPath(superPathFile);
          fail("expected AccessControlException");
        } catch (AccessControlException e) {
          assertExceptionContains("Permission denied:", e);
        }

        assertNull("expected null for nonexistent path",
            userAdmin.getEncryptionZoneForPath(nonexistent));

        // Check operation with non-ez paths
        assertNull("expected null for non-ez path",
            userAdmin.getEncryptionZoneForPath(nonEZDir));
        assertNull("expected null for non-ez path",
            userAdmin.getEncryptionZoneForPath(nonEZFile));

        // Check operation with snapshots
        String snapshottedAllPath = newSnap.toString() + allPath.toString();
        assertEquals("expected ez path", allPath.toString(),
            userAdmin.getEncryptionZoneForPath(
                new Path(snapshottedAllPath)).getPath().toString());

        /*
         * Delete the file from the non-snapshot and test that it is still ok
         * in the ez.
         */
        fs.delete(allPathFile, false);
        assertEquals("expected ez path", allPath.toString(),
            userAdmin.getEncryptionZoneForPath(
                new Path(snapshottedAllPath)).getPath().toString());

        // Delete the ez and make sure ss's ez is still ok.
        fs.delete(allPath, true);
        assertEquals("expected ez path", allPath.toString(),
            userAdmin.getEncryptionZoneForPath(
                new Path(snapshottedAllPath)).getPath().toString());
        assertNull("expected null for deleted file path",
            userAdmin.getEncryptionZoneForPath(allPathFile));
        assertNull("expected null for deleted directory path",
            userAdmin.getEncryptionZoneForPath(allPath));
        return null;
      }
    });
  }

  /**
   * Test success of Rename EZ on a directory which is already an EZ.
   */
  private void doRenameEncryptionZone(FSTestWrapper wrapper) throws Exception {
    final Path testRoot = new Path("/tmp/TestEncryptionZones");
    final Path pathFoo = new Path(testRoot, "foo");
    final Path pathFooBaz = new Path(pathFoo, "baz");
    final Path pathFooBazFile = new Path(pathFooBaz, "file");
    final Path pathFooBar = new Path(pathFoo, "bar");
    final Path pathFooBarFile = new Path(pathFooBar, "file");
    final int len = 8192;
    wrapper.mkdir(pathFoo, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(pathFoo, TEST_KEY, NO_TRASH);
    wrapper.mkdir(pathFooBaz, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, pathFooBazFile, len, (short) 1, 0xFEED);
    String contents = DFSTestUtil.readFile(fs, pathFooBazFile);
    try {
      wrapper.rename(pathFooBaz, testRoot);
    } catch (IOException e) {
      assertExceptionContains(pathFooBaz.toString() + " can't be moved from" +
              " an encryption zone.", e
      );
    }

    // Verify that we can rename dir and files within an encryption zone.
    assertTrue(fs.rename(pathFooBaz, pathFooBar));
    assertTrue("Rename of dir and file within ez failed",
        !wrapper.exists(pathFooBaz) && wrapper.exists(pathFooBar));
    assertEquals("Renamed file contents not the same",
        contents, DFSTestUtil.readFile(fs, pathFooBarFile));

    // Verify that we can rename an EZ root
    final Path newFoo = new Path(testRoot, "newfoo");
    assertTrue("Rename of EZ root", fs.rename(pathFoo, newFoo));
    assertTrue("Rename of EZ root failed",
        !wrapper.exists(pathFoo) && wrapper.exists(newFoo));

    // Verify that we can't rename an EZ root onto itself
    try {
      wrapper.rename(newFoo, newFoo);
    } catch (IOException e) {
      assertExceptionContains("are the same", e);
    }
  }

  @Test
  public void testRenameFileSystem() throws Exception {
    doRenameEncryptionZone(fsWrapper);
  }

  @Test
  public void testRenameFileContext() throws Exception {
    doRenameEncryptionZone(fcWrapper);
  }

  private FileEncryptionInfo getFileEncryptionInfo(Path path) throws Exception {
    LocatedBlocks blocks = fs.getClient().getLocatedBlocks(path.toString(), 0);
    return blocks.getFileEncryptionInfo();
  }

  @Test
  public void testReadWrite() throws Exception {
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    // Create a base file for comparison
    final Path baseFile = new Path("/base");
    final int len = 8192;
    DFSTestUtil.createFile(fs, baseFile, len, (short) 1, 0xFEED);
    // Create the first enc file
    final Path zone = new Path("/zone");
    fs.mkdirs(zone);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    final Path encFile1 = new Path(zone, "myfile");
    DFSTestUtil.createFile(fs, encFile1, len, (short) 1, 0xFEED);
    // Read them back in and compare byte-by-byte
    verifyFilesEqual(fs, baseFile, encFile1, len);
    // Roll the key of the encryption zone
    assertNumZones(1);
    String keyName = dfsAdmin.listEncryptionZones().next().getKeyName();
    cluster.getNamesystem().getProvider().rollNewVersion(keyName);
    cluster.getNamesystem().getProvider().invalidateCache(keyName);
    // Read them back in and compare byte-by-byte
    verifyFilesEqual(fs, baseFile, encFile1, len);
    // Write a new enc file and validate
    final Path encFile2 = new Path(zone, "myfile2");
    DFSTestUtil.createFile(fs, encFile2, len, (short) 1, 0xFEED);
    // FEInfos should be different
    FileEncryptionInfo feInfo1 = getFileEncryptionInfo(encFile1);
    FileEncryptionInfo feInfo2 = getFileEncryptionInfo(encFile2);
    assertFalse("EDEKs should be different", Arrays
        .equals(feInfo1.getEncryptedDataEncryptionKey(),
            feInfo2.getEncryptedDataEncryptionKey()));
    assertNotEquals("Key was rolled, versions should be different",
        feInfo1.getEzKeyVersionName(), feInfo2.getEzKeyVersionName());
    // Contents still equal
    verifyFilesEqual(fs, encFile1, encFile2, len);
  }

  @Test
  public void testReadWriteUsingWebHdfs() throws Exception {
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    final FileSystem webHdfsFs = WebHdfsTestUtil.getWebHdfsFileSystem(conf,
        WebHdfsConstants.WEBHDFS_SCHEME);

    final Path zone = new Path("/zone");
    fs.mkdirs(zone);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);

    /* Create an unencrypted file for comparison purposes. */
    final Path unencFile = new Path("/unenc");
    final int len = 8192;
    DFSTestUtil.createFile(webHdfsFs, unencFile, len, (short) 1, 0xFEED);

    /*
     * Create the same file via webhdfs, but this time encrypted. Compare it
     * using both webhdfs and DFS.
     */
    final Path encFile1 = new Path(zone, "myfile");
    DFSTestUtil.createFile(webHdfsFs, encFile1, len, (short) 1, 0xFEED);
    verifyFilesEqual(webHdfsFs, unencFile, encFile1, len);
    verifyFilesEqual(fs, unencFile, encFile1, len);

    /*
     * Same thing except this time create the encrypted file using DFS.
     */
    final Path encFile2 = new Path(zone, "myfile2");
    DFSTestUtil.createFile(fs, encFile2, len, (short) 1, 0xFEED);
    verifyFilesEqual(webHdfsFs, unencFile, encFile2, len);
    verifyFilesEqual(fs, unencFile, encFile2, len);

    /* Verify appending to files works correctly. */
    appendOneByte(fs, unencFile);
    appendOneByte(webHdfsFs, encFile1);
    appendOneByte(fs, encFile2);
    verifyFilesEqual(webHdfsFs, unencFile, encFile1, len);
    verifyFilesEqual(fs, unencFile, encFile1, len);
    verifyFilesEqual(webHdfsFs, unencFile, encFile2, len);
    verifyFilesEqual(fs, unencFile, encFile2, len);
  }

  private void appendOneByte(FileSystem fs, Path p) throws IOException {
    final FSDataOutputStream out = fs.append(p);
    out.write((byte) 0x123);
    out.close();
  }

  @Test
  public void testVersionAndSuiteNegotiation() throws Exception {
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    final Path zone = new Path("/zone");
    fs.mkdirs(zone);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    // Create a file in an EZ, which should succeed
    DFSTestUtil
        .createFile(fs, new Path(zone, "success1"), 0, (short) 1, 0xFEED);
    // Pass no supported versions, fail
    DFSOutputStream.SUPPORTED_CRYPTO_VERSIONS = new CryptoProtocolVersion[] {};
    try {
      DFSTestUtil.createFile(fs, new Path(zone, "fail"), 0, (short) 1, 0xFEED);
      fail("Created a file without specifying a crypto protocol version");
    } catch (UnknownCryptoProtocolVersionException e) {
      assertExceptionContains("No crypto protocol versions", e);
    }
    // Pass some unknown versions, fail
    DFSOutputStream.SUPPORTED_CRYPTO_VERSIONS = new CryptoProtocolVersion[]
        { CryptoProtocolVersion.UNKNOWN, CryptoProtocolVersion.UNKNOWN };
    try {
      DFSTestUtil.createFile(fs, new Path(zone, "fail"), 0, (short) 1, 0xFEED);
      fail("Created a file without specifying a known crypto protocol version");
    } catch (UnknownCryptoProtocolVersionException e) {
      assertExceptionContains("No crypto protocol versions", e);
    }
    // Pass some unknown and a good cipherSuites, success
    DFSOutputStream.SUPPORTED_CRYPTO_VERSIONS =
        new CryptoProtocolVersion[] {
            CryptoProtocolVersion.UNKNOWN,
            CryptoProtocolVersion.UNKNOWN,
            CryptoProtocolVersion.ENCRYPTION_ZONES };
    DFSTestUtil
        .createFile(fs, new Path(zone, "success2"), 0, (short) 1, 0xFEED);
    DFSOutputStream.SUPPORTED_CRYPTO_VERSIONS =
        new CryptoProtocolVersion[] {
            CryptoProtocolVersion.ENCRYPTION_ZONES,
            CryptoProtocolVersion.UNKNOWN,
            CryptoProtocolVersion.UNKNOWN} ;
    DFSTestUtil
        .createFile(fs, new Path(zone, "success3"), 4096, (short) 1, 0xFEED);
    // Check KeyProvider state
    // Flushing the KP on the NN, since it caches, and init a test one
    cluster.getNamesystem().getProvider().flush();
    KeyProvider provider = KeyProviderFactory.get(new URI(conf.getTrimmed(
        CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH)),
        conf);
    List<String> keys = provider.getKeys();
    assertEquals("Expected NN to have created one key per zone", 1,
        keys.size());
    List<KeyProvider.KeyVersion> allVersions = Lists.newArrayList();
    for (String key : keys) {
      List<KeyProvider.KeyVersion> versions = provider.getKeyVersions(key);
      assertEquals("Should only have one key version per key", 1,
          versions.size());
      allVersions.addAll(versions);
    }
    // Check that the specified CipherSuite was correctly saved on the NN
    for (int i = 2; i <= 3; i++) {
      FileEncryptionInfo feInfo =
          getFileEncryptionInfo(new Path(zone.toString() +
              "/success" + i));
      assertEquals(feInfo.getCipherSuite(), CipherSuite.AES_CTR_NOPADDING);
    }

    DFSClient old = fs.dfs;
    try {
      testCipherSuiteNegotiation(fs, conf);
    } finally {
      fs.dfs = old;
    }
  }

  @SuppressWarnings("unchecked")
  private static void mockCreate(ClientProtocol mcp,
      CipherSuite suite, CryptoProtocolVersion version) throws Exception {
    Mockito.doReturn(new HdfsFileStatus.Builder()
          .replication(1)
          .blocksize(1024)
          .perm(new FsPermission((short) 777))
          .owner("owner")
          .group("group")
          .symlink(new byte[0])
          .path(new byte[0])
          .fileId(1010)
          .feInfo(new FileEncryptionInfo(suite, version,
              new byte[suite.getAlgorithmBlockSize()],
              new byte[suite.getAlgorithmBlockSize()],
              "fakeKey", "fakeVersion"))
          .build())
        .when(mcp)
        .create(anyString(), any(), anyString(), any(), anyBoolean(),
            anyShort(), anyLong(), any(), any(), any());
  }

  // This test only uses mocks. Called from the end of an existing test to
  // avoid an extra mini cluster.
  private static void testCipherSuiteNegotiation(DistributedFileSystem fs,
      Configuration conf) throws Exception {
    // Set up mock ClientProtocol to test client-side CipherSuite negotiation
    final ClientProtocol mcp = Mockito.mock(ClientProtocol.class);

    // Try with an empty conf
    final Configuration noCodecConf = new Configuration(conf);
    final CipherSuite suite = CipherSuite.AES_CTR_NOPADDING;
    final String confKey = CommonConfigurationKeysPublic
        .HADOOP_SECURITY_CRYPTO_CODEC_CLASSES_KEY_PREFIX + suite
        .getConfigSuffix();
    noCodecConf.set(confKey, "");
    fs.dfs = new DFSClient(null, mcp, noCodecConf, null);
    mockCreate(mcp, suite, CryptoProtocolVersion.ENCRYPTION_ZONES);
    Mockito.when(mcp.complete(anyString(), anyString(), any(), anyLong()))
        .thenReturn(true);
    try {
      fs.create(new Path("/mock"));
      fail("Created with no configured codecs!");
    } catch (UnknownCipherSuiteException e) {
      assertExceptionContains("No configuration found for the cipher", e);
    }

    // Try create with an UNKNOWN CipherSuite
    fs.dfs = new DFSClient(null, mcp, conf, null);
    CipherSuite unknown = CipherSuite.UNKNOWN;
    unknown.setUnknownValue(989);
    mockCreate(mcp, unknown, CryptoProtocolVersion.ENCRYPTION_ZONES);
    try {
      fs.create(new Path("/mock"));
      fail("Created with unknown cipher!");
    } catch (IOException e) {
      assertExceptionContains("unknown CipherSuite with ID 989", e);
    }
  }

  @Test
  public void testCreateEZWithNoProvider() throws Exception {
    // Unset the key provider and make sure EZ ops don't work
    final Configuration clusterConf = cluster.getConfiguration(0);
    clusterConf
        .unset(CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH);
    cluster.restartNameNode(true);
    final Path zone1 = new Path("/zone1");
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    try {
      dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
      fail("expected exception");
    } catch (IOException e) {
      assertExceptionContains("since no key provider is available", e);
    }
    final Path jksPath = new Path(testRootDir.toString(), "test.jks");
    clusterConf
        .set(CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH,
            JavaKeyStoreProvider.SCHEME_NAME + "://file" + jksPath.toUri()
    );
    // Try listing EZs as well
    assertNumZones(0);
  }

  @Test
  public void testIsEncryptedMethod() throws Exception {
    doTestIsEncryptedMethod(new Path("/"));
    doTestIsEncryptedMethod(new Path("/.reserved/raw"));
  }

  private void doTestIsEncryptedMethod(Path prefix) throws Exception {
    try {
      dTIEM(prefix);
    } finally {
      for (FileStatus s : fsWrapper.listStatus(prefix)) {
        fsWrapper.delete(s.getPath(), true);
      }
    }
  }

  private void dTIEM(Path prefix) throws Exception {
    final HdfsAdmin dfsAdmin =
      new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    // Create an unencrypted file to check isEncrypted returns false
    final Path baseFile = new Path(prefix, "base");
    fsWrapper.createFile(baseFile);
    FileStatus stat = fsWrapper.getFileStatus(baseFile);
    assertFalse("Expected isEncrypted to return false for " + baseFile,
        stat.isEncrypted());

    // Create an encrypted file to check isEncrypted returns true
    final Path zone = new Path(prefix, "zone");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    final Path encFile = new Path(zone, "encfile");
    fsWrapper.createFile(encFile);
    stat = fsWrapper.getFileStatus(encFile);
    assertTrue("Expected isEncrypted to return true for enc file" + encFile,
        stat.isEncrypted());

    // check that it returns true for an ez root
    stat = fsWrapper.getFileStatus(zone);
    assertTrue("Expected isEncrypted to return true for ezroot",
        stat.isEncrypted());

    // check that it returns true for a dir in the ez
    final Path zoneSubdir = new Path(zone, "subdir");
    fsWrapper.mkdir(zoneSubdir, FsPermission.getDirDefault(), true);
    stat = fsWrapper.getFileStatus(zoneSubdir);
    assertTrue(
        "Expected isEncrypted to return true for ez subdir " + zoneSubdir,
        stat.isEncrypted());

    // check that it returns false for a non ez dir
    final Path nonEzDirPath = new Path(prefix, "nonzone");
    fsWrapper.mkdir(nonEzDirPath, FsPermission.getDirDefault(), true);
    stat = fsWrapper.getFileStatus(nonEzDirPath);
    assertFalse(
        "Expected isEncrypted to return false for directory " + nonEzDirPath,
        stat.isEncrypted());

    // check that it returns true for listings within an ez
    FileStatus[] statuses = fsWrapper.listStatus(zone);
    for (FileStatus s : statuses) {
      assertTrue("Expected isEncrypted to return true for ez stat " + zone,
          s.isEncrypted());
    }

    statuses = fsWrapper.listStatus(encFile);
    for (FileStatus s : statuses) {
      assertTrue(
          "Expected isEncrypted to return true for ez file stat " + encFile,
          s.isEncrypted());
    }

    // check that it returns false for listings outside an ez
    statuses = fsWrapper.listStatus(nonEzDirPath);
    for (FileStatus s : statuses) {
      assertFalse(
          "Expected isEncrypted to return false for nonez stat " + nonEzDirPath,
          s.isEncrypted());
    }

    statuses = fsWrapper.listStatus(baseFile);
    for (FileStatus s : statuses) {
      assertFalse(
          "Expected isEncrypted to return false for non ez stat " + baseFile,
          s.isEncrypted());
    }
  }

  @Test
  public void testEncryptionZonesWithSnapshots() throws Exception {
    final Path snapshottable = new Path("/zones");
    fsWrapper.mkdir(snapshottable, FsPermission.getDirDefault(),
        true);
    dfsAdmin.allowSnapshot(snapshottable);
    dfsAdmin.createEncryptionZone(snapshottable, TEST_KEY, NO_TRASH);
    fs.createSnapshot(snapshottable, "snap1");
    SnapshotDiffReport report =
        fs.getSnapshotDiffReport(snapshottable, "snap1", "");
    Assert.assertEquals(0, report.getDiffList().size());
    report =
        fs.getSnapshotDiffReport(snapshottable, "snap1", "");
    System.out.println(report);
    Assert.assertEquals(0, report.getDiffList().size());
    fs.setSafeMode(SafeModeAction.ENTER);
    fs.saveNamespace();
    fs.setSafeMode(SafeModeAction.LEAVE);
    cluster.restartNameNode(true);
    report =
        fs.getSnapshotDiffReport(snapshottable, "snap1", "");
    Assert.assertEquals(0, report.getDiffList().size());
  }

  private class AuthorizationExceptionInjector extends EncryptionFaultInjector {
    @Override
    public void ensureKeyIsInitialized() throws IOException {
      throw new AuthorizationException(AUTHORIZATION_EXCEPTION_MESSAGE);
    }
  }

  @Test
  public void testExceptionInformationReturn() {
    /* Test exception information can be returned when
    creating transparent encryption zone.*/
    final Path zone1 = new Path("/zone1");
    EncryptionFaultInjector.instance = new AuthorizationExceptionInjector();
    try {
      dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
      fail("exception information can be returned when creating " +
          "transparent encryption zone");
    } catch (IOException e) {
      assertTrue(e instanceof RemoteException);
      assertTrue(((RemoteException) e).unwrapRemoteException()
          instanceof AuthorizationException);
      assertExceptionContains(AUTHORIZATION_EXCEPTION_MESSAGE, e);
    }
  }

  private class MyInjector extends EncryptionFaultInjector {
    volatile int generateCount;
    CountDownLatch ready;
    CountDownLatch wait;

    public MyInjector() {
      this.ready = new CountDownLatch(1);
      this.wait = new CountDownLatch(1);
    }

    @Override
    public void startFileNoKey() throws IOException {
      generateCount = -1;
      syncWithLatches();
    }

    @Override
    public void startFileBeforeGenerateKey() throws IOException {
      syncWithLatches();
    }

    private void syncWithLatches() throws IOException {
      ready.countDown();
      try {
        wait.await();
      } catch (InterruptedException e) {
        throw new IOException(e);
      }
    }

    @Override
    public void startFileAfterGenerateKey() throws IOException {
      generateCount++;
    }
  }

  private class CreateFileTask implements Callable<Void> {
    private FileSystemTestWrapper fsWrapper;
    private Path name;

    CreateFileTask(FileSystemTestWrapper fsWrapper, Path name) {
      this.fsWrapper = fsWrapper;
      this.name = name;
    }

    @Override
    public Void call() throws Exception {
      fsWrapper.createFile(name);
      return null;
    }
  }

  private class InjectFaultTask implements Callable<Void> {
    final Path zone1 = new Path("/zone1");
    final Path file = new Path(zone1, "file1");
    final ExecutorService executor = Executors.newSingleThreadExecutor();

    MyInjector injector;

    @Override
    public Void call() throws Exception {
      // Set up the injector
      injector = new MyInjector();
      EncryptionFaultInjector.instance = injector;
      Future<Void> future =
          executor.submit(new CreateFileTask(fsWrapper, file));
      injector.ready.await();
      try {
        // Do the fault
        doFault();
        // Allow create to proceed
      } finally {
        // Always decrement latch to avoid hanging the tests on failure.
        injector.wait.countDown();
      }
      future.get();
      // Cleanup and postconditions
      doCleanup();
      return null;
    }

    public void doFault() throws Exception {}

    public void doCleanup() throws Exception {}
  }

  /**
   * Tests the retry logic in startFile. We release the lock while generating
   * an EDEK, so tricky things can happen in the intervening time.
   */
  @Test
  public void testStartFileRetry() throws Exception {
    final Path zone1 = new Path("/zone1");
    final Path file = new Path(zone1, "file1");
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    ExecutorService executor = Executors.newSingleThreadExecutor();

    // Test when the parent directory becomes an EZ.  With no initial EZ,
    // the fsn lock must not be yielded.
    executor.submit(new InjectFaultTask() {
      @Override
      public void doCleanup() throws Exception {
        assertEquals("Expected no startFile key generation",
            -1, injector.generateCount);
        fsWrapper.delete(file, false);
      }
    }).get();

    // Test when the parent directory unbecomes an EZ.  The generation of
    // the EDEK will yield the lock, then re-resolve the path and use the
    // previous EDEK.
    dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
    executor.submit(new InjectFaultTask() {
      @Override
      public void doFault() throws Exception {
        fsWrapper.delete(zone1, true);
      }
      @Override
      public void doCleanup() throws Exception {
        assertEquals("Expected no startFile retries", 1, injector.generateCount);
        fsWrapper.delete(file, false);
      }
    }).get();

    // Test when the parent directory becomes a different EZ.  The generation
    // of the EDEK will yield the lock, re-resolve will detect the EZ has
    // changed, and client will be asked to retry a 2nd time
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    final String otherKey = "other_key";
    DFSTestUtil.createKey(otherKey, cluster, conf);
    dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);

    executor.submit(new InjectFaultTask() {
      @Override
      public void doFault() throws Exception {
        fsWrapper.delete(zone1, true);
        fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
        dfsAdmin.createEncryptionZone(zone1, otherKey, NO_TRASH);
      }
      @Override
      public void doCleanup() throws Exception {
        assertEquals("Expected a startFile retry", 2, injector.generateCount);
        fsWrapper.delete(zone1, true);
      }
    }).get();

    // Test that the retry limit leads to an error
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    final String anotherKey = "another_key";
    DFSTestUtil.createKey(anotherKey, cluster, conf);
    dfsAdmin.createEncryptionZone(zone1, anotherKey, NO_TRASH);
    String keyToUse = otherKey;

    MyInjector injector = new MyInjector();
    EncryptionFaultInjector.instance = injector;
    Future<?> future = executor.submit(new CreateFileTask(fsWrapper, file));

    // Flip-flop between two EZs to repeatedly fail
    for (int i=0; i<DFSOutputStream.CREATE_RETRY_COUNT+1; i++) {
      injector.ready.await();
      fsWrapper.delete(zone1, true);
      fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
      dfsAdmin.createEncryptionZone(zone1, keyToUse, NO_TRASH);
      if (keyToUse == otherKey) {
        keyToUse = anotherKey;
      } else {
        keyToUse = otherKey;
      }
      injector.wait.countDown();
      injector = new MyInjector();
      EncryptionFaultInjector.instance = injector;
    }
    try {
      future.get();
      fail("Expected exception from too many retries");
    } catch (ExecutionException e) {
      assertExceptionContains(
          "Too many retries because of encryption zone operations",
          e.getCause());
    }
  }

  /**
   * Tests obtaining delegation token from stored key
   */
  @Test
  public void testDelegationToken() throws Exception {
    UserGroupInformation.createRemoteUser("JobTracker");
    DistributedFileSystem dfs = cluster.getFileSystem();
    KeyProvider keyProvider = Mockito.mock(KeyProvider.class,
        withSettings().extraInterfaces(
            DelegationTokenExtension.class,
            CryptoExtension.class));
    Mockito.when(keyProvider.getConf()).thenReturn(conf);
    byte[] testIdentifier = "Test identifier for delegation token".getBytes();

    @SuppressWarnings("rawtypes")
    Token testToken = new Token(testIdentifier, new byte[0],
        new Text(), new Text());
    Mockito.when(((DelegationTokenIssuer)keyProvider).
        getCanonicalServiceName()).thenReturn("service");
    Mockito.when(((DelegationTokenIssuer)keyProvider).
        getDelegationToken(anyString())).
        thenReturn(testToken);

    dfs.getClient().setKeyProvider(keyProvider);

    Credentials creds = new Credentials();
    final Token<?> tokens[] = dfs.addDelegationTokens("JobTracker", creds);
    DistributedFileSystem.LOG.debug("Delegation tokens: " +
        Arrays.asList(tokens));
    Assert.assertEquals(2, tokens.length);
    Assert.assertEquals(tokens[1], testToken);
    Assert.assertEquals(2, creds.numberOfTokens());
  }

  /**
   * Test running fsck on a system with encryption zones.
   */
  @Test
  public void testFsckOnEncryptionZones() throws Exception {
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone1 = new Path(zoneParent, "zone1");
    final Path zone1File = new Path(zone1, "file");
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, zone1File, len, (short) 1, 0xFEED);
    ByteArrayOutputStream bStream = new ByteArrayOutputStream();
    PrintStream out = new PrintStream(bStream, true);
    int errCode = ToolRunner.run(new DFSck(conf, out),
        new String[]{ "/" });
    assertEquals("Fsck ran with non-zero error code", 0, errCode);
    String result = bStream.toString();
    assertTrue("Fsck did not return HEALTHY status",
        result.contains(NamenodeFsck.HEALTHY_STATUS));

    // Run fsck directly on the encryption zone instead of root
    errCode = ToolRunner.run(new DFSck(conf, out),
        new String[]{ zoneParent.toString() });
    assertEquals("Fsck ran with non-zero error code", 0, errCode);
    result = bStream.toString();
    assertTrue("Fsck did not return HEALTHY status",
        result.contains(NamenodeFsck.HEALTHY_STATUS));
  }

  /**
   * Test correctness of successive snapshot creation and deletion
   * on a system with encryption zones.
   */
  @Test
  public void testSnapshotsOnEncryptionZones() throws Exception {
    final String TEST_KEY2 = "testkey2";
    DFSTestUtil.createKey(TEST_KEY2, cluster, conf);

    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    final Path zoneFile = new Path(zone, "zoneFile");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.allowSnapshot(zoneParent);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, zoneFile, len, (short) 1, 0xFEED);
    String contents = DFSTestUtil.readFile(fs, zoneFile);
    final Path snap1 = fs.createSnapshot(zoneParent, "snap1");
    final Path snap1Zone = new Path(snap1, zone.getName());
    assertEquals("Got unexpected ez path", zone.toString(),
        dfsAdmin.getEncryptionZoneForPath(snap1Zone).getPath().toString());

    // Now delete the encryption zone, recreate the dir, and take another
    // snapshot
    fsWrapper.delete(zone, true);
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    final Path snap2 = fs.createSnapshot(zoneParent, "snap2");
    final Path snap2Zone = new Path(snap2, zone.getName());
    assertEquals("Got unexpected ez path", zone.toString(),
        dfsAdmin.getEncryptionZoneForPath(snap1Zone).getPath().toString());
    assertNull("Expected null ez path",
        dfsAdmin.getEncryptionZoneForPath(snap2Zone));

    // Create the encryption zone again, and that shouldn't affect old snapshot
    dfsAdmin.createEncryptionZone(zone, TEST_KEY2, NO_TRASH);
    EncryptionZone ezSnap1 = dfsAdmin.getEncryptionZoneForPath(snap1Zone);
    assertEquals("Got unexpected ez path", zone.toString(),
        ezSnap1.getPath().toString());
    assertEquals("Unexpected ez key", TEST_KEY, ezSnap1.getKeyName());
    assertNull("Expected null ez path",
        dfsAdmin.getEncryptionZoneForPath(snap2Zone));

    final Path snap3 = fs.createSnapshot(zoneParent, "snap3");
    final Path snap3Zone = new Path(snap3, zone.getName());
    // Check that snap3's EZ has the correct settings
    EncryptionZone ezSnap3 = dfsAdmin.getEncryptionZoneForPath(snap3Zone);
    assertEquals("Got unexpected ez path", zone.toString(),
        ezSnap3.getPath().toString());
    assertEquals("Unexpected ez key", TEST_KEY2, ezSnap3.getKeyName());
    // Check that older snapshots still have the old EZ settings
    ezSnap1 = dfsAdmin.getEncryptionZoneForPath(snap1Zone);
    assertEquals("Got unexpected ez path", zone.toString(),
        ezSnap1.getPath().toString());
    assertEquals("Unexpected ez key", TEST_KEY, ezSnap1.getKeyName());
    assertNull("Expected null ez path",
        dfsAdmin.getEncryptionZoneForPath(snap2Zone));

    // Check that listEZs only shows the current filesystem state
    ArrayList<EncryptionZone> listZones = Lists.newArrayList();
    RemoteIterator<EncryptionZone> it = dfsAdmin.listEncryptionZones();
    while (it.hasNext()) {
      listZones.add(it.next());
    }
    for (EncryptionZone z: listZones) {
      System.out.println(z);
    }
    assertEquals("Did not expect additional encryption zones!", 1,
        listZones.size());
    EncryptionZone listZone = listZones.get(0);
    assertEquals("Got unexpected ez path", zone.toString(),
        listZone.getPath().toString());
    assertEquals("Unexpected ez key", TEST_KEY2, listZone.getKeyName());

    // Verify contents of the snapshotted file
    final Path snapshottedZoneFile = new Path(
        snap1.toString() + "/" + zone.getName() + "/" + zoneFile.getName());
    assertEquals("Contents of snapshotted file have changed unexpectedly",
        contents, DFSTestUtil.readFile(fs, snapshottedZoneFile));

    // Now delete the snapshots out of order and verify the zones are still
    // correct
    fs.deleteSnapshot(zoneParent, snap2.getName());
    assertEquals("Got unexpected ez path", zone.toString(),
        dfsAdmin.getEncryptionZoneForPath(snap1Zone).getPath().toString());
    assertEquals("Got unexpected ez path", zone.toString(),
        dfsAdmin.getEncryptionZoneForPath(snap3Zone).getPath().toString());
    fs.deleteSnapshot(zoneParent, snap1.getName());
    assertEquals("Got unexpected ez path", zone.toString(),
        dfsAdmin.getEncryptionZoneForPath(snap3Zone).getPath().toString());
  }

  /**
   * Test correctness of encryption zones on a existing snapshot path.
   * Specifically, test the file in encryption zones with no encryption info
   */
  @Test
  public void testSnapshotWithFile() throws Exception {
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone = new Path(zoneParent, "zone");
    final Path zoneFile = new Path(zone, "zoneFile");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    DFSTestUtil.createFile(fs, zoneFile, len, (short) 1, 0xFEED);
    String contents = DFSTestUtil.readFile(fs, zoneFile);

    // Create the snapshot which contains the file
    dfsAdmin.allowSnapshot(zoneParent);
    final Path snap1 = fs.createSnapshot(zoneParent, "snap1");

    // Now delete the file and create encryption zone
    fsWrapper.delete(zoneFile, false);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    assertEquals("Got unexpected ez path", zone.toString(),
        dfsAdmin.getEncryptionZoneForPath(zone).getPath());

    // The file in snapshot shouldn't have any encryption info
    final Path snapshottedZoneFile = new Path(
        snap1 + "/" + zone.getName() + "/" + zoneFile.getName());
    FileEncryptionInfo feInfo = getFileEncryptionInfo(snapshottedZoneFile);
    assertNull("Expected null ez info", feInfo);
    assertEquals("Contents of snapshotted file have changed unexpectedly",
        contents, DFSTestUtil.readFile(fs, snapshottedZoneFile));
  }

  /**
   * Check the correctness of the diff reports.
   */
  private void verifyDiffReport(Path dir, String from, String to,
      DiffReportEntry... entries) throws IOException {
    DFSTestUtil.verifySnapshotDiffReport(fs, dir, from, to, entries);
  }

  /**
   * Test correctness of snapshotDiff for encryption zone.
   * snapshtoDiff should work when the path parameter is prefixed with
   * /.reserved/raw for path that's both snapshottable and encryption zone.
   */
  @Test
  public void testSnapshotDiffOnEncryptionZones() throws Exception {
    final String TEST_KEY2 = "testkey2";
    DFSTestUtil.createKey(TEST_KEY2, cluster, conf);

    final int len = 8196;
    final Path zone = new Path("/zone");
    final Path rawZone = new Path("/.reserved/raw/zone");
    final Path zoneFile = new Path(zone, "zoneFile");
    fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
    dfsAdmin.allowSnapshot(zone);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, zoneFile, len, (short) 1, 0xFEED);
    fs.createSnapshot(zone, "snap1");
    fsWrapper.delete(zoneFile, true);
    fs.createSnapshot(zone, "snap2");
    verifyDiffReport(zone, "snap1", "snap2",
        new DiffReportEntry(DiffType.MODIFY, DFSUtil.string2Bytes("")),
        new DiffReportEntry(DiffType.DELETE, DFSUtil.string2Bytes("zoneFile")));

    verifyDiffReport(rawZone, "snap1", "snap2",
        new DiffReportEntry(DiffType.MODIFY, DFSUtil.string2Bytes("")),
        new DiffReportEntry(DiffType.DELETE, DFSUtil.string2Bytes("zoneFile")));
  }

  /**
   * Verify symlinks can be created in encryption zones and that
   * they function properly when the target is in the same
   * or different ez.
   */
  @Test
  public void testEncryptionZonesWithSymlinks() throws Exception {
    // Verify we can create an encryption zone over both link and target
    final int len = 8192;
    final Path parent = new Path("/parent");
    final Path linkParent = new Path(parent, "symdir1");
    final Path targetParent = new Path(parent, "symdir2");
    final Path link = new Path(linkParent, "link");
    final Path target = new Path(targetParent, "target");
    fs.mkdirs(parent);
    dfsAdmin.createEncryptionZone(parent, TEST_KEY, NO_TRASH);
    fs.mkdirs(linkParent);
    fs.mkdirs(targetParent);
    DFSTestUtil.createFile(fs, target, len, (short)1, 0xFEED);
    String content = DFSTestUtil.readFile(fs, target);
    fs.createSymlink(target, link, false);
    assertEquals("Contents read from link are not the same as target",
        content, DFSTestUtil.readFile(fs, link));
    fs.delete(parent, true);

    // Now let's test when the symlink and target are in different
    // encryption zones
    fs.mkdirs(linkParent);
    fs.mkdirs(targetParent);
    dfsAdmin.createEncryptionZone(linkParent, TEST_KEY, NO_TRASH);
    dfsAdmin.createEncryptionZone(targetParent, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, target, len, (short)1, 0xFEED);
    content = DFSTestUtil.readFile(fs, target);
    fs.createSymlink(target, link, false);
    assertEquals("Contents read from link are not the same as target",
        content, DFSTestUtil.readFile(fs, link));
    fs.delete(link, true);
    fs.delete(target, true);
  }

  @Test
  public void testConcatFailsInEncryptionZones() throws Exception {
    final int len = 8192;
    final Path ez = new Path("/ez");
    fs.mkdirs(ez);
    dfsAdmin.createEncryptionZone(ez, TEST_KEY, NO_TRASH);
    final Path src1 = new Path(ez, "src1");
    final Path src2 = new Path(ez, "src2");
    final Path target = new Path(ez, "target");
    DFSTestUtil.createFile(fs, src1, len, (short)1, 0xFEED);
    DFSTestUtil.createFile(fs, src2, len, (short)1, 0xFEED);
    DFSTestUtil.createFile(fs, target, len, (short)1, 0xFEED);
    try {
      fs.concat(target, new Path[] { src1, src2 });
      fail("expected concat to throw en exception for files in an ez");
    } catch (IOException e) {
      assertExceptionContains(
          "concat can not be called for files in an encryption zone", e);
    }
    fs.delete(ez, true);
  }

  /**
   * Test running the OfflineImageViewer on a system with encryption zones.
   */
  @Test
  public void testOfflineImageViewerOnEncryptionZones() throws Exception {
    final int len = 8196;
    final Path zoneParent = new Path("/zones");
    final Path zone1 = new Path(zoneParent, "zone1");
    final Path zone1File = new Path(zone1, "file");
    fsWrapper.mkdir(zone1, FsPermission.getDirDefault(), true);
    dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, zone1File, len, (short) 1, 0xFEED);
    fs.setSafeMode(SafeModeAction.ENTER, false);
    fs.saveNamespace();

    File originalFsimage = FSImageTestUtil.findLatestImageFile(FSImageTestUtil
        .getFSImage(cluster.getNameNode()).getStorage().getStorageDir(0));
    if (originalFsimage == null) {
      throw new RuntimeException("Didn't generate or can't find fsimage");
    }

    // Run the XML OIV processor
    ByteArrayOutputStream output = new ByteArrayOutputStream();
    PrintStream pw = new PrintStream(output);
    PBImageXmlWriter v = new PBImageXmlWriter(new Configuration(), pw);
    v.visit(new RandomAccessFile(originalFsimage, "r"));
    final String xml = output.toString();
    SAXParser parser = XMLUtils.newSecureSAXParserFactory().newSAXParser();
    parser.parse(new InputSource(new StringReader(xml)), new DefaultHandler());
  }

  /**
   * Test creating encryption zone on the root path
   */
  @Test
  public void testEncryptionZonesOnRootPath() throws Exception {
    final int len = 8196;
    final Path rootDir = new Path("/");
    final Path zoneFile = new Path(rootDir, "file");
    final Path rawFile = new Path("/.reserved/raw/file");
    dfsAdmin.createEncryptionZone(rootDir, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, zoneFile, len, (short) 1, 0xFEED);

    assertEquals("File can be created on the root encryption zone " +
            "with correct length",
        len, fs.getFileStatus(zoneFile).getLen());
    assertEquals("Root dir is encrypted",
        true, fs.getFileStatus(rootDir).isEncrypted());
    assertEquals("File is encrypted",
        true, fs.getFileStatus(zoneFile).isEncrypted());
  }

  @Test
  public void testEncryptionZonesOnRelativePath() throws Exception {
    final int len = 8196;
    final Path baseDir = new Path("/somewhere/base");
    final Path zoneDir = new Path("zone");
    final Path zoneFile = new Path("file");
    fs.setWorkingDirectory(baseDir);
    fs.mkdirs(zoneDir);
    dfsAdmin.createEncryptionZone(zoneDir, TEST_KEY, NO_TRASH);
    DFSTestUtil.createFile(fs, zoneFile, len, (short) 1, 0xFEED);

    assertNumZones(1);
    assertZonePresent(TEST_KEY, "/somewhere/base/zone");

    assertEquals("Got unexpected ez path", "/somewhere/base/zone", dfsAdmin
        .getEncryptionZoneForPath(zoneDir).getPath().toString());
  }

  @Test
  public void testGetEncryptionZoneOnANonExistentPaths() throws Exception {
    final Path ezPath = new Path("/ez");
    fs.mkdirs(ezPath);
    dfsAdmin.createEncryptionZone(ezPath, TEST_KEY, NO_TRASH);
    Path zoneFile = new Path(ezPath, "file");
    EncryptionZone ez = fs.getEZForPath(zoneFile);
    assertNotNull("Expected EZ for non-existent path in EZ", ez);
    ez = dfsAdmin.getEncryptionZoneForPath(zoneFile);
    assertNotNull("Expected EZ for non-existent path in EZ", ez);
    ez = dfsAdmin.getEncryptionZoneForPath(
        new Path("/does/not/exist"));
    assertNull("Expected null for non-existent path not in EZ", ez);
  }

  @Test
  public void testEncryptionZoneWithTrash() throws Exception {
    // Create the encryption zone1
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    final Path zone1 = new Path("/zone1");
    fs.mkdirs(zone1);
    dfsAdmin.createEncryptionZone(zone1, TEST_KEY, NO_TRASH);

    // Create the encrypted file in zone1
    final Path encFile1 = new Path(zone1, "encFile1");
    final int len = 8192;
    DFSTestUtil.createFile(fs, encFile1, len, (short) 1, 0xFEED);

    Configuration clientConf = new Configuration(conf);
    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
    FsShell shell = new FsShell(clientConf);

    // Delete encrypted file from the shell with trash enabled
    // Verify the file is moved to appropriate trash within the zone
    verifyShellDeleteWithTrash(shell, encFile1);

    // Delete encryption zone from the shell with trash enabled
    // Verify the zone is moved to appropriate trash location in user's home dir
    verifyShellDeleteWithTrash(shell, zone1);

    final Path topEZ = new Path("/topEZ");
    fs.mkdirs(topEZ);
    dfsAdmin.createEncryptionZone(topEZ, TEST_KEY, NO_TRASH);
    final String NESTED_EZ_TEST_KEY = "nested_ez_test_key";
    DFSTestUtil.createKey(NESTED_EZ_TEST_KEY, cluster, conf);
    final Path nestedEZ = new Path(topEZ, "nestedEZ");
    fs.mkdirs(nestedEZ);
    dfsAdmin.createEncryptionZone(nestedEZ, NESTED_EZ_TEST_KEY, NO_TRASH);
    final Path topEZFile = new Path(topEZ, "file");
    final Path nestedEZFile = new Path(nestedEZ, "file");
    DFSTestUtil.createFile(fs, topEZFile, len, (short) 1, 0xFEED);
    DFSTestUtil.createFile(fs, nestedEZFile, len, (short) 1, 0xFEED);
    verifyShellDeleteWithTrash(shell, topEZFile);
    verifyShellDeleteWithTrash(shell, nestedEZFile);

    //Test nested EZ with webHDFS
    final WebHdfsFileSystem webFS = WebHdfsTestUtil.getWebHdfsFileSystem(
        conf, WebHdfsConstants.WEBHDFS_SCHEME);
    final String currentUser =
        UserGroupInformation.getCurrentUser().getShortUserName();
    final Path expectedTopTrash = new Path(topEZ,
        new Path(FileSystem.TRASH_PREFIX, currentUser));
    final Path expectedNestedTrash = new Path(nestedEZ,
        new Path(FileSystem.TRASH_PREFIX, currentUser));

    final Path topTrash = webFS.getTrashRoot(topEZFile);
    final Path nestedTrash = webFS.getTrashRoot(nestedEZFile);

    assertEquals(expectedTopTrash.toUri().getPath(),
        topTrash.toUri().getPath());
    assertEquals(expectedNestedTrash.toUri().getPath(),
        nestedTrash.toUri().getPath());

    verifyShellDeleteWithTrash(shell, nestedEZ);
    verifyShellDeleteWithTrash(shell, topEZ);
  }

  @Test
  public void testRootDirEZTrash() throws Exception {
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    final String currentUser =
        UserGroupInformation.getCurrentUser().getShortUserName();
    final Path rootDir = new Path("/");
    dfsAdmin.createEncryptionZone(rootDir, TEST_KEY, NO_TRASH);
    final Path encFile = new Path("/encFile");
    final int len = 8192;
    DFSTestUtil.createFile(fs, encFile, len, (short) 1, 0xFEED);
    Configuration clientConf = new Configuration(conf);
    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
    FsShell shell = new FsShell(clientConf);
    verifyShellDeleteWithTrash(shell, encFile);

    // Trash path should be consistent
    // if root path is an encryption zone
    Path encFileCurrentTrash = shell.getCurrentTrashDir(encFile);
    Path rootDirCurrentTrash = shell.getCurrentTrashDir(rootDir);
    assertEquals("Root trash should be equal with ezFile trash",
        encFileCurrentTrash, rootDirCurrentTrash);

    // Use webHDFS client to test trash root path
    final WebHdfsFileSystem webFS = WebHdfsTestUtil.getWebHdfsFileSystem(
        conf, WebHdfsConstants.WEBHDFS_SCHEME);
    final Path expectedTrash = new Path(rootDir,
        new Path(FileSystem.TRASH_PREFIX, currentUser));

    Path webHDFSTrash = webFS.getTrashRoot(encFile);
    assertEquals(expectedTrash.toUri().getPath(),
        webHDFSTrash.toUri().getPath());
    assertEquals(encFileCurrentTrash.getParent().toUri().getPath(),
        webHDFSTrash.toUri().getPath());

  }

  @Test
  public void testGetTrashRoots() throws Exception {
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    Path ezRoot1 = new Path("/ez1");
    fs.mkdirs(ezRoot1);
    dfsAdmin.createEncryptionZone(ezRoot1, TEST_KEY, NO_TRASH);
    Path ezRoot2 = new Path("/ez2");
    fs.mkdirs(ezRoot2);
    dfsAdmin.createEncryptionZone(ezRoot2, TEST_KEY, NO_TRASH);
    Path ezRoot3 = new Path("/ez3");
    fs.mkdirs(ezRoot3);
    dfsAdmin.createEncryptionZone(ezRoot3, TEST_KEY, NO_TRASH);
    Collection<FileStatus> trashRootsBegin = fs.getTrashRoots(true);
    assertEquals("Unexpected getTrashRoots result", 0, trashRootsBegin.size());

    final Path encFile = new Path(ezRoot2, "encFile");
    final int len = 8192;
    DFSTestUtil.createFile(fs, encFile, len, (short) 1, 0xFEED);
    Configuration clientConf = new Configuration(conf);
    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
    FsShell shell = new FsShell(clientConf);
    verifyShellDeleteWithTrash(shell, encFile);

    Collection<FileStatus> trashRootsDelete1 = fs.getTrashRoots(true);
    assertEquals("Unexpected getTrashRoots result", 1,
        trashRootsDelete1.size());

    final Path nonEncFile = new Path("/nonEncFile");
    DFSTestUtil.createFile(fs, nonEncFile, len, (short) 1, 0xFEED);
    verifyShellDeleteWithTrash(shell, nonEncFile);

    Collection<FileStatus> trashRootsDelete2 = fs.getTrashRoots(true);
    assertEquals("Unexpected getTrashRoots result", 2,
        trashRootsDelete2.size());
  }

  private void verifyShellDeleteWithTrash(FsShell shell, Path path)
      throws Exception{
    try {
      Path trashDir = shell.getCurrentTrashDir(path);
      // Verify that trashDir has a path component named ".Trash"
      Path checkTrash = trashDir;
      while (!checkTrash.isRoot() && !checkTrash.getName().equals(".Trash")) {
        checkTrash = checkTrash.getParent();
      }
      assertEquals("No .Trash component found in trash dir " + trashDir,
          ".Trash", checkTrash.getName());
      final Path trashFile =
          new Path(shell.getCurrentTrashDir(path) + "/" + path);
      String[] argv = new String[]{"-rm", "-r", path.toString()};
      int res = ToolRunner.run(shell, argv);
      assertEquals("rm failed", 0, res);
      assertTrue("File not in trash : " + trashFile, fs.exists(trashFile));
    } catch (IOException ioe) {
      fail(ioe.getMessage());
    } finally {
      if (fs.exists(path)) {
        fs.delete(path, true);
      }
    }
  }

  /** This test tests that client will first lookup secrets map
   * for key provider uri from {@link Credentials} in
   * {@link UserGroupInformation}
   * @throws Exception
   */
  @Test
  public void testProviderUriInCredentials() throws Exception {
    String dummyKeyProvider = "dummy://foo:bar@test_provider1";
    DFSClient client = cluster.getFileSystem().getClient();
    Credentials credentials = new Credentials();
    // Key provider uri should be in the secret map of credentials object with
    // namenode uri as key
    Text lookUpKey = HdfsKMSUtil.getKeyProviderMapKey(
        cluster.getFileSystem().getUri());
    credentials.addSecretKey(lookUpKey,
        DFSUtilClient.string2Bytes(dummyKeyProvider));
    client.ugi.addCredentials(credentials);
    Assert.assertEquals("Client Key provider is different from provider in "
        + "credentials map", dummyKeyProvider,
        client.getKeyProviderUri().toString());
  }


 /**
  * Testing the fallback behavior of keyProviderUri.
  * This test tests first the key provider uri is used from conf
  * and then used from serverDefaults.
  * @throws IOException
  */
  @Test
  public void testKeyProviderFallBackBehavior() throws IOException {
    Configuration clusterConf = cluster.getConfiguration(0);
    String dummyKeyProviderUri1 = "dummy://foo:bar@test_provider1";
    // set the key provider uri in conf.
    clusterConf.set(
        CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH,
        dummyKeyProviderUri1);
    DFSClient mockClient = Mockito.spy(cluster.getFileSystem().getClient());
    // Namenode returning null as keyProviderUri in FSServerDefaults.
    FsServerDefaults serverDefaultsWithKeyProviderNull =
        getTestServerDefaults(null);
    Mockito.doReturn(serverDefaultsWithKeyProviderNull)
        .when(mockClient).getServerDefaults();
    Assert.assertEquals(
        "Key provider uri from client doesn't match with uri from conf",
        dummyKeyProviderUri1, mockClient.getKeyProviderUri().toString());
    Mockito.verify(mockClient, Mockito.times(1)).getServerDefaults();

    String dummyKeyProviderUri2 = "dummy://foo:bar@test_provider2";
    FsServerDefaults serverDefaultsWithDummyKeyProvider =
        getTestServerDefaults(dummyKeyProviderUri2);
    // Namenode returning dummyKeyProvider2 in serverDefaults.
    Mockito.doReturn(serverDefaultsWithDummyKeyProvider)
    .when(mockClient).getServerDefaults();
    Assert.assertEquals(
        "Key provider uri from client doesn't match with uri from namenode",
        dummyKeyProviderUri2, mockClient.getKeyProviderUri().toString());
    Mockito.verify(mockClient, Mockito.times(2)).getServerDefaults();
  }

  /**
   * This test makes sure the client gets the key provider uri from namenode
   * instead of its own conf.
   * This test assumes both the namenode and client are upgraded.
   * @throws Exception
   */
  @Test
  public void testDifferentKMSProviderOnUpgradedNamenode() throws Exception {
    Configuration clusterConf = cluster.getConfiguration(0);
    URI namenodeKeyProviderUri = URI.create(getKeyProviderURI());
    Assert.assertEquals("Key Provider for client and namenode are different",
        namenodeKeyProviderUri, cluster.getFileSystem().getClient()
        .getKeyProviderUri());

    // Unset the provider path in conf
    clusterConf.unset(
        CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH);
    // Even after unsetting the local conf, the client key provider should be
    // the same as namenode's provider.
    Assert.assertEquals("Key Provider for client and namenode are different",
        namenodeKeyProviderUri, cluster.getFileSystem().getClient()
        .getKeyProviderUri());

    // Set the provider path to some dummy scheme.
    clusterConf.set(
        CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH,
        "dummy://foo:bar@test_provider1");
    // Even after pointing the conf to some dummy provider, the client key
    // provider should be the same as namenode's provider.
    Assert.assertEquals("Key Provider for client and namenode are different",
        namenodeKeyProviderUri, cluster.getFileSystem().getClient()
        .getKeyProviderUri());

    // Ignore the key provider from NN.
    clusterConf.setBoolean(
        DFS_CLIENT_IGNORE_NAMENODE_DEFAULT_KMS_URI, true);
    Assert.assertEquals("Expecting Key Provider for client config",
        "dummy://foo:bar@test_provider1", cluster.getFileSystem().getClient()
            .getKeyProviderUri().toString());
    Assert.assertNotEquals("Key Provider for client and namenode is different",
        namenodeKeyProviderUri, cluster.getFileSystem().getClient()
            .getKeyProviderUri().toString());
  }

  /**
   * This test makes sure the client trusts its local conf
   * This test assumes the client is upgraded but the namenode is not.
   * @throws Exception
   */
  @Test
  public void testDifferentKMSProviderOnUnUpgradedNamenode()
      throws Exception {
    Configuration clusterConf = cluster.getConfiguration(0);
    URI namenodeKeyProviderUri = URI.create(getKeyProviderURI());
    URI clientKeyProviderUri =
        cluster.getFileSystem().getClient().getKeyProviderUri();
    Assert.assertNotNull(clientKeyProviderUri);
    // Since the client and the namenode share the same conf, they will have
    // identical key provider.
    Assert.assertEquals("Key Provider for client and namenode are different",
        namenodeKeyProviderUri, clientKeyProviderUri);

    String dummyKeyProviderUri = "dummy://foo:bar@test_provider";
    // Unset the provider path in conf.
    clusterConf.set(
        CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH,
        dummyKeyProviderUri);
    FsServerDefaults spyServerDefaults = getTestServerDefaults(null);
    // Creating a fake serverdefaults so that we can simulate namenode not
    // being upgraded.
    DFSClient spyClient = Mockito.spy(cluster.getFileSystem().getClient());
    Mockito.doReturn(spyServerDefaults).when(spyClient).getServerDefaults();

    // Since FsServerDefaults#keyProviderUri is null, the client
    // will fallback to local conf which is null.
    clientKeyProviderUri = spyClient.getKeyProviderUri();
    Assert.assertEquals("Client keyProvider should be " + dummyKeyProviderUri,
        dummyKeyProviderUri, clientKeyProviderUri.toString());
    Mockito.verify(spyClient, Mockito.times(1)).getServerDefaults();
  }

  // Given a provider uri return serverdefaults.
  // provider uri == null means the namenode does not support returning
  // provider uri in FSServerDefaults object.
  private FsServerDefaults getTestServerDefaults(String providerPath) {
    FsServerDefaults serverDefaults = new FsServerDefaults(
        conf.getLongBytes(DFS_BLOCK_SIZE_KEY, DFS_BLOCK_SIZE_DEFAULT),
        conf.getInt(DFS_BYTES_PER_CHECKSUM_KEY, DFS_BYTES_PER_CHECKSUM_DEFAULT),
        conf.getInt(DFS_CLIENT_WRITE_PACKET_SIZE_KEY,
        DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT),
        (short) conf.getInt(DFS_REPLICATION_KEY, DFS_REPLICATION_DEFAULT),
        conf.getInt(IO_FILE_BUFFER_SIZE_KEY, IO_FILE_BUFFER_SIZE_DEFAULT),
        conf.getBoolean(
        DFS_ENCRYPT_DATA_TRANSFER_KEY, DFS_ENCRYPT_DATA_TRANSFER_DEFAULT),
        conf.getLong(FS_TRASH_INTERVAL_KEY, FS_TRASH_INTERVAL_DEFAULT),
        DataChecksum.Type.valueOf(DFSConfigKeys.DFS_CHECKSUM_TYPE_DEFAULT),
        providerPath);
    return serverDefaults;
  }

  /**
   * This test performs encrypted read/write and picks up the key provider uri
   * from the credentials and not the conf.
   * @throws Exception
   */
  @Test
  public void testEncryptedReadWriteUsingDiffKeyProvider() throws Exception {
    final HdfsAdmin dfsAdmin =
        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
    Configuration clusterConf = cluster.getConfiguration(0);
    clusterConf.unset(
        CommonConfigurationKeysPublic.HADOOP_SECURITY_KEY_PROVIDER_PATH);
    DFSClient client = cluster.getFileSystem().getClient();
    Credentials credentials = new Credentials();
    Text lookUpKey = HdfsKMSUtil.
        getKeyProviderMapKey(cluster.getFileSystem().getUri());
    credentials.addSecretKey(lookUpKey,
        DFSUtilClient.string2Bytes(getKeyProviderURI()));
    client.ugi.addCredentials(credentials);
    // Create a base file for comparison
    final Path baseFile = new Path("/base");
    final int len = 8192;
    DFSTestUtil.createFile(fs, baseFile, len, (short) 1, 0xFEED);
    // Create the first enc file
    final Path zone = new Path("/zone");
    fs.mkdirs(zone);
    dfsAdmin.createEncryptionZone(zone, TEST_KEY, NO_TRASH);
    final Path encFile1 = new Path(zone, "myfile");
    DFSTestUtil.createFile(fs, encFile1, len, (short) 1, 0xFEED);
    // Read them back in and compare byte-by-byte
    verifyFilesEqual(fs, baseFile, encFile1, len);
  }

  /**
   * Test listing encryption zones after zones had been deleted,
   * but still exist under snapshots. This test first moves EZs
   * to trash folder, so that an inodereference is created for the EZ,
   * then it removes the EZ from trash folder to emulate condition where
   * the EZ inode will not be complete.
   */
  @Test
  public void testListEncryptionZonesWithSnapshots() throws Exception {
    final Path snapshottable = new Path("/zones");
    final Path zoneDirectChild = new Path(snapshottable, "zone1");
    final Path snapshottableChild = new Path(snapshottable, "child");
    final Path zoneSubChild = new Path(snapshottableChild, "zone2");
    fsWrapper.mkdir(zoneDirectChild, FsPermission.getDirDefault(),
        true);
    fsWrapper.mkdir(zoneSubChild, FsPermission.getDirDefault(),
        true);
    dfsAdmin.allowSnapshot(snapshottable);
    dfsAdmin.createEncryptionZone(zoneDirectChild, TEST_KEY, NO_TRASH);
    dfsAdmin.createEncryptionZone(zoneSubChild, TEST_KEY, NO_TRASH);
    final Path snap1 = fs.createSnapshot(snapshottable, "snap1");
    Configuration clientConf = new Configuration(conf);
    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
    FsShell shell = new FsShell(clientConf);
    //will "trash" the zone under subfolder of snapshottable directory
    verifyShellDeleteWithTrash(shell, snapshottableChild);
    //permanently remove zone under subfolder of snapshottable directory
    fsWrapper.delete(shell.getCurrentTrashDir(snapshottableChild),
        true);
    final RemoteIterator<EncryptionZone> it = dfsAdmin.listEncryptionZones();
    boolean match = false;
    while (it.hasNext()) {
      EncryptionZone ez = it.next();
      assertNotEquals("EncryptionZone " + zoneSubChild.toString() +
          " should not be listed.",
          ez.getPath(), zoneSubChild.toString());
    }
    //will "trash" the zone direct child of snapshottable directory
    verifyShellDeleteWithTrash(shell, zoneDirectChild);
    //permanently remove zone direct child of snapshottable directory
    fsWrapper.delete(shell.getCurrentTrashDir(zoneDirectChild), true);
    assertFalse("listEncryptionZones should not return anything, " +
            "since both EZs were deleted.",
        dfsAdmin.listEncryptionZones().hasNext());
  }

  /**
  * This test returns mocked kms token when
  * {@link WebHdfsFileSystem#addDelegationTokens(String, Credentials)} method
  * is called.
  * @throws Exception
  */
  @Test
  public void addMockKmsToken() throws Exception {
    UserGroupInformation.createRemoteUser("JobTracker");
    WebHdfsFileSystem webfs = WebHdfsTestUtil.getWebHdfsFileSystem(conf,
        WebHdfsConstants.WEBHDFS_SCHEME);
    KeyProvider keyProvider = Mockito.mock(KeyProvider.class, withSettings()
        .extraInterfaces(DelegationTokenExtension.class,
         CryptoExtension.class));
    Mockito.when(keyProvider.getConf()).thenReturn(conf);
    byte[] testIdentifier = "Test identifier for delegation token".getBytes();

    Token testToken = new Token(testIdentifier, new byte[0],
        new Text("kms-dt"), new Text());
    Mockito.when(((DelegationTokenIssuer)keyProvider).
        getCanonicalServiceName()).thenReturn("service");
    Mockito.when(((DelegationTokenIssuer)keyProvider).
        getDelegationToken(anyString())).
        thenReturn(testToken);

    webfs.setTestProvider(keyProvider);
    Credentials creds = new Credentials();
    final Token<?>[] tokens =
        webfs.addDelegationTokens("JobTracker", creds);

    Assert.assertEquals(2, tokens.length);
    Assert.assertEquals(tokens[1], testToken);
    Assert.assertEquals(2, creds.numberOfTokens());
  }

  /**
   * Creates a file with stable {@link DistributedFileSystem}.
   * Tests the following 2 scenarios.
   * 1. The decrypted data using {@link WebHdfsFileSystem} should be same as
   * input data.
   * 2. Gets the underlying raw encrypted stream and verifies that the
   * encrypted data is different than input data.
   * @throws Exception
   */
  @Test
  public void testWebhdfsRead() throws Exception {
    Path zonePath = new Path("/TestEncryptionZone");
    fsWrapper.mkdir(zonePath, FsPermission.getDirDefault(), false);
    dfsAdmin.createEncryptionZone(zonePath, TEST_KEY, NO_TRASH);
    final Path encryptedFilePath =
        new Path("/TestEncryptionZone/encryptedFile.txt");
    final Path rawPath = 
        new Path("/.reserved/raw/TestEncryptionZone/encryptedFile.txt");
    final String content = "hello world";

    // Create a file using DistributedFileSystem.
    DFSTestUtil.writeFile(fs, encryptedFilePath, content);
    final FileSystem webhdfs = WebHdfsTestUtil.getWebHdfsFileSystem(conf,
        WebHdfsConstants.WEBHDFS_SCHEME);
    // Verify whether decrypted input stream data is same as content.
    InputStream decryptedIputStream  = webhdfs.open(encryptedFilePath);
    verifyStreamsSame(content, decryptedIputStream);

    // Get the underlying stream from CryptoInputStream which should be
    // raw encrypted bytes.
    InputStream cryptoStream =
        webhdfs.open(encryptedFilePath).getWrappedStream();
    Assert.assertTrue("cryptoStream should be an instance of "
        + "CryptoInputStream", (cryptoStream instanceof CryptoInputStream));
    InputStream encryptedStream =
        ((CryptoInputStream)cryptoStream).getWrappedStream();
    // Verify that the data read from the raw input stream is different
    // from the original content. Also check it is identical to the raw
    // encrypted data from dfs.
    verifyRaw(content, encryptedStream, fs.open(rawPath));
  }

  private void verifyStreamsSame(String content, InputStream is)
      throws IOException {
    byte[] streamBytes;
    try (ByteArrayOutputStream os = new ByteArrayOutputStream()) {
      IOUtils.copyBytes(is, os, 1024, true);
      streamBytes = os.toByteArray();
    }
    Assert.assertArrayEquals(content.getBytes(), streamBytes);
  }

  private void verifyRaw(String content, InputStream is, InputStream rawIs)
      throws IOException {
    byte[] streamBytes, rawBytes;
    try (ByteArrayOutputStream os = new ByteArrayOutputStream()) {
      IOUtils.copyBytes(is, os, 1024, true);
      streamBytes = os.toByteArray();
    }
    Assert.assertFalse(Arrays.equals(content.getBytes(), streamBytes));

    // webhdfs raw bytes should match the raw bytes from dfs.
    try (ByteArrayOutputStream os = new ByteArrayOutputStream()) {
      IOUtils.copyBytes(rawIs, os, 1024, true);
      rawBytes = os.toByteArray();
    }
    Assert.assertArrayEquals(rawBytes, streamBytes);
  }

  /* Tests that if client is old and namenode is new then the
   * data will be decrypted by datanode.
   * @throws Exception
   */
  @Test
  public void testWebhdfsReadOldBehavior() throws Exception {
    Path zonePath = new Path("/TestEncryptionZone");
    fsWrapper.mkdir(zonePath, FsPermission.getDirDefault(), false);
    dfsAdmin.createEncryptionZone(zonePath, TEST_KEY, NO_TRASH);
    final Path encryptedFilePath = new Path("/TestEncryptionZone/foo");
    final String content = "hello world";
    // Create a file using DistributedFileSystem.
    DFSTestUtil.writeFile(fs, encryptedFilePath, content);

    InetSocketAddress addr = cluster.getNameNode().getHttpAddress();
    URL url = new URL("http", addr.getHostString(), addr.getPort(),
        WebHdfsFileSystem.PATH_PREFIX + encryptedFilePath.toString()
        + "?op=OPEN");
    // Return a connection with client not supporting EZ.
    HttpURLConnection namenodeConnection = returnConnection(url, "GET", false);
    String location = namenodeConnection.getHeaderField("Location");
    URL datanodeURL = new URL(location);
    String path = datanodeURL.getPath();
    Assert.assertEquals(
        WebHdfsFileSystem.PATH_PREFIX + encryptedFilePath.toString(), path);
    HttpURLConnection datanodeConnection = returnConnection(datanodeURL,
        "GET", false);
    InputStream in = datanodeConnection.getInputStream();
    // Comparing with the original contents
    // and making sure they are decrypted.
    verifyStreamsSame(content, in);
  }

  /* Tests namenode returns path starting with /.reserved/raw if client
   * supports EZ and not if otherwise
   * @throws Exception
   */
  @Test
  public void testWebhfsEZRedirectLocation()
      throws Exception {
    Path zonePath = new Path("/TestEncryptionZone");
    fsWrapper.mkdir(zonePath, FsPermission.getDirDefault(), false);
    dfsAdmin.createEncryptionZone(zonePath, TEST_KEY, NO_TRASH);
    final Path encryptedFilePath =
        new Path("/TestEncryptionZone/foo");
    final String content = "hello world";
    // Create a file using DistributedFileSystem.
    DFSTestUtil.writeFile(fs, encryptedFilePath, content);

    InetSocketAddress addr = cluster.getNameNode().getHttpAddress();
    URL url = new URL("http", addr.getHostString(), addr.getPort(),
        WebHdfsFileSystem.PATH_PREFIX + encryptedFilePath.toString()
        + "?op=OPEN");
    // Return a connection with client not supporting EZ.
    HttpURLConnection namenodeConnection =
        returnConnection(url, "GET", false);
    Assert.assertNotNull(namenodeConnection.getHeaderField("Location"));
    URL datanodeUrl = new URL(namenodeConnection.getHeaderField("Location"));
    Assert.assertNotNull(datanodeUrl);
    String path = datanodeUrl.getPath();
    Assert.assertEquals(
        WebHdfsFileSystem.PATH_PREFIX + encryptedFilePath.toString(), path);

    url = new URL("http", addr.getHostString(), addr.getPort(),
        WebHdfsFileSystem.PATH_PREFIX + encryptedFilePath.toString()
        + "?op=OPEN");
    // Return a connection with client supporting EZ.
    namenodeConnection = returnConnection(url, "GET", true);
    Assert.assertNotNull(namenodeConnection.getHeaderField("Location"));
    datanodeUrl = new URL(namenodeConnection.getHeaderField("Location"));
    Assert.assertNotNull(datanodeUrl);
    path = datanodeUrl.getPath();
    Assert.assertEquals(WebHdfsFileSystem.PATH_PREFIX
        + "/.reserved/raw" + encryptedFilePath.toString(), path);
  }

  private static HttpURLConnection returnConnection(URL url,
      String httpRequestType, boolean supportEZ) throws Exception {
    HttpURLConnection conn = null;
    conn = (HttpURLConnection) url.openConnection();
    conn.setRequestMethod(httpRequestType);
    conn.setDoOutput(true);
    conn.setInstanceFollowRedirects(false);
    if (supportEZ) {
      conn.setRequestProperty(WebHdfsFileSystem.EZ_HEADER, "true");
    }
    return conn;
  }

  /*
   * Test seek behavior of the webhdfs input stream which reads data from
   * encryption zone.
   */
  @Test
  public void testPread() throws Exception {
    Path zonePath = new Path("/TestEncryptionZone");
    fsWrapper.mkdir(zonePath, FsPermission.getDirDefault(), false);
    dfsAdmin.createEncryptionZone(zonePath, TEST_KEY, NO_TRASH);
    final Path encryptedFilePath =
        new Path("/TestEncryptionZone/foo");
    // Create a file using DistributedFileSystem.
    WebHdfsFileSystem webfs = WebHdfsTestUtil.getWebHdfsFileSystem(conf,
        WebHdfsConstants.WEBHDFS_SCHEME);
    DFSTestUtil.createFile(webfs, encryptedFilePath, 1024, (short)1, 0xFEED);
    byte[] data = DFSTestUtil.readFileAsBytes(fs, encryptedFilePath);
    FSDataInputStream in = webfs.open(encryptedFilePath);
    for (int i = 0; i < 1024; i++) {
      in.seek(i);
      Assert.assertEquals((data[i] & 0XFF), in.read());
    }
  }

  /**
   * Tests that namenode doesn't generate edek if we are writing to
   * /.reserved/raw directory.
   * @throws Exception
   */
  @Test
  public void testWriteToEZReservedRaw() throws Exception {
    String unEncryptedBytes = "hello world";
    // Create an Encryption Zone.
    final Path zonePath = new Path("/zone");
    fsWrapper.mkdir(zonePath, FsPermission.getDirDefault(), false);
    dfsAdmin.createEncryptionZone(zonePath, TEST_KEY, NO_TRASH);
    Path p1 = new Path(zonePath, "p1");
    Path reservedRawPath = new Path("/.reserved/raw/" + p1.toString());
    // Create an empty file with /.reserved/raw/ path.
    OutputStream os = fs.create(reservedRawPath);
    os.close();
    try {
      fs.getXAttr(reservedRawPath, HdfsServerConstants
          .CRYPTO_XATTR_FILE_ENCRYPTION_INFO);
      fail("getXAttr should have thrown an exception");
    } catch (IOException ioe) {
      assertExceptionContains("At least one of the attributes provided was " +
          "not found.", ioe);
    }
  }
}
