io.trino.hdfs.authentication.CachingKerberosHadoopAuthentication Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of trino-hdfs Show documentation

Trino - Legacy HDFS file system support

There is a newer version: 465

/*
 * Licensed 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 io.trino.hdfs.authentication;

import com.google.errorprone.annotations.concurrent.GuardedBy;
import org.apache.hadoop.security.UserGroupInformation;

import javax.security.auth.Subject;
import javax.security.auth.kerberos.KerberosTicket;

import java.util.Set;

import static com.google.common.base.Preconditions.checkArgument;
import static io.trino.plugin.base.authentication.KerberosTicketUtils.getRefreshTime;
import static io.trino.plugin.base.authentication.KerberosTicketUtils.getTicketGrantingTicket;
import static java.util.Objects.requireNonNull;

public class CachingKerberosHadoopAuthentication
        implements HadoopAuthentication
{
    private final KerberosHadoopAuthentication delegate;

    private final UserGroupInformation userGroupInformation;
    @GuardedBy("this")
    private long nextRefreshTime;

    public CachingKerberosHadoopAuthentication(KerberosHadoopAuthentication delegate)
    {
        this.delegate = requireNonNull(delegate, "delegate is null");
        this.userGroupInformation = requireNonNull(delegate.getUserGroupInformation(), "delegate.getUserGroupInformation() is null");
        nextRefreshTime = calculateNextRefreshTime(userGroupInformation);
    }

    @Override
    public synchronized UserGroupInformation getUserGroupInformation()
    {
        if (nextRefreshTime < System.currentTimeMillis()) {
            Subject existingSubject = userGroupInformation.getSubject();
            UserGroupInformation newUserGroupInformation = requireNonNull(delegate.getUserGroupInformation(), "delegate.getUserGroupInformation() is null");
            Subject newSubject = newUserGroupInformation.getSubject();

            // We modify the existing UGI's credentials in-place instead of returning new UGI because some parts of Hadoop code reuse UGI (e.g. DFSClient)
            // We also need to clear the old credentials because JDK assumes that the first credential is the TGT which is not always true
            existingSubject.getPrincipals().addAll(newSubject.getPrincipals());
            Set