org.apache.tez.common.security.TokenCache.java Source code

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Here is the source code for org.apache.tez.common.security.TokenCache.java

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/**
 * 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.tez.common.security;

import java.io.IOException;
import java.util.HashSet;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.security.Credentials;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.security.token.TokenIdentifier;

/**
 * This class provides user facing APIs for transferring secrets from
 * the job client to the tasks.
 * The secrets can be stored just before submission of jobs and read during
 * the task execution.  
 */
@InterfaceAudience.Private
@InterfaceStability.Unstable
public class TokenCache {

    private static final Log LOG = LogFactory.getLog(TokenCache.class);

    /**
     * auxiliary method to get user's secret keys..
     * @param alias
     * @return secret key from the storage
     */
    public static byte[] getSecretKey(Credentials credentials, Text alias) {
        if (credentials == null)
            return null;
        return credentials.getSecretKey(alias);
    }

    /**
     * Convenience method to obtain delegation tokens from namenodes 
     * corresponding to the paths passed.
     * @param credentials
     * @param ps array of paths
     * @param conf configuration
     * @throws IOException
     */
    public static void obtainTokensForFileSystems(Credentials credentials, Path[] ps, Configuration conf)
            throws IOException {
        if (!UserGroupInformation.isSecurityEnabled()) {
            return;
        }
        obtainTokensForFileSystemsInternal(credentials, ps, conf);
    }

    static void obtainTokensForFileSystemsInternal(Credentials credentials, Path[] ps, Configuration conf)
            throws IOException {
        Set<FileSystem> fsSet = new HashSet<FileSystem>();
        for (Path p : ps) {
            fsSet.add(p.getFileSystem(conf));
        }
        for (FileSystem fs : fsSet) {
            obtainTokensForFileSystemsInternal(fs, credentials, conf);
        }
    }

    /**
     * get delegation token for a specific FS
     * @param fs
     * @param credentials
     * @param p
     * @param conf
     * @throws IOException
     */
    static void obtainTokensForFileSystemsInternal(FileSystem fs, Credentials credentials, Configuration conf)
            throws IOException {
        // TODO Change this to use YARN utilities once YARN-1664 is fixed.
        String delegTokenRenewer = Master.getMasterPrincipal(conf);
        if (delegTokenRenewer == null || delegTokenRenewer.length() == 0) {
            throw new IOException("Can't get Master Kerberos principal for use as renewer");
        }

        final Token<?> tokens[] = fs.addDelegationTokens(delegTokenRenewer, credentials);
        if (tokens != null) {
            for (Token<?> token : tokens) {
                LOG.info("Got dt for " + fs.getUri() + "; " + token);
            }
        }
    }

    private static final Text SESSION_TOKEN = new Text("SessionToken");

    /**
     * store session specific token
     * @param t
     */
    @InterfaceAudience.Private
    public static void setSessionToken(Token<? extends TokenIdentifier> t, Credentials credentials) {
        credentials.addToken(SESSION_TOKEN, t);
    }

    /**
     * 
     * @return session token
     */
    @SuppressWarnings("unchecked")
    @InterfaceAudience.Private
    public static Token<JobTokenIdentifier> getSessionToken(Credentials credentials) {
        Token<?> token = credentials.getToken(SESSION_TOKEN);
        if (token == null) {
            return null;
        }
        return (Token<JobTokenIdentifier>) token;
    }

    /**
     * Merge tokens from a configured binary file into provided Credentials object
     * @param creds Credentials object to add new tokens to
     * @param tokenFilePath Location of tokens' binary file
     */
    @InterfaceAudience.Private
    public static void mergeBinaryTokens(Credentials creds, Configuration conf, String tokenFilePath)
            throws IOException {
        if (tokenFilePath == null || tokenFilePath.isEmpty()) {
            throw new RuntimeException("Invalid file path provided" + ", tokenFilePath=" + tokenFilePath);
        }
        LOG.info("Merging additional tokens from binary file" + ", binaryFileName=" + tokenFilePath);
        Credentials binary = Credentials.readTokenStorageFile(new Path("file:///" + tokenFilePath), conf);

        // supplement existing tokens with the tokens in the binary file
        creds.mergeAll(binary);
    }

}