| /** |
| * 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.IOException; |
| import java.net.URI; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.hdfs.protocol.HdfsConstants; |
| import org.apache.hadoop.io.Text; |
| import org.apache.hadoop.security.Credentials; |
| import org.apache.hadoop.security.UserGroupInformation; |
| import org.apache.hadoop.security.token.DtFetcher; |
| import org.apache.hadoop.security.token.Token; |
| |
| |
| /** |
| * DtFetcher is an interface which permits the abstraction and separation of |
| * delegation token fetch implementaions across different packages and |
| * compilation units. Resolution of fetcher impl will be done at runtime. |
| */ |
| public class HdfsDtFetcher implements DtFetcher { |
| private static final Log LOG = LogFactory.getLog(HdfsDtFetcher.class); |
| |
| private static final String SERVICE_NAME = HdfsConstants.HDFS_URI_SCHEME; |
| |
| private static final String FETCH_FAILED = "Fetch of delegation token failed"; |
| |
| /** |
| * Returns the service name for HDFS, which is also a valid URL prefix. |
| */ |
| public Text getServiceName() { |
| return new Text(SERVICE_NAME); |
| } |
| |
| public boolean isTokenRequired() { |
| return UserGroupInformation.isSecurityEnabled(); |
| } |
| |
| /** |
| * Returns Token object via FileSystem, null if bad argument. |
| * @param conf - a Configuration object used with FileSystem.get() |
| * @param creds - a Credentials object to which token(s) will be added |
| * @param renewer - the renewer to send with the token request |
| * @param url - the URL to which the request is sent |
| * @return a Token, or null if fetch fails. |
| */ |
| public Token<?> addDelegationTokens(Configuration conf, Credentials creds, |
| String renewer, String url) throws Exception { |
| if (!url.startsWith(getServiceName().toString())) { |
| url = getServiceName().toString() + "://" + url; |
| } |
| FileSystem fs = FileSystem.get(URI.create(url), conf); |
| Token<?> token = fs.getDelegationToken(renewer); |
| if (token == null) { |
| LOG.error(FETCH_FAILED); |
| throw new IOException(FETCH_FAILED); |
| } |
| creds.addToken(token.getService(), token); |
| return token; |
| } |
| } |