content: /*
   *
   * 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.bookkeeper.sasl;
  
  import java.io.IOException;
  import java.net.InetAddress;
  import java.net.InetSocketAddress;
  import java.net.SocketAddress;
  import javax.security.auth.Subject;
  import javax.security.sasl.SaslException;
  import org.apache.bookkeeper.auth.AuthCallbacks;
  import org.apache.bookkeeper.auth.AuthToken;
  import org.apache.bookkeeper.auth.ClientAuthProvider;
  import org.apache.bookkeeper.client.BKException;
  import org.apache.bookkeeper.proto.ClientConnectionPeer;
  import org.slf4j.LoggerFactory;
  
  /**
   * SASL Client Authentication Provider.
   */
  public class SASLClientAuthProvider implements ClientAuthProvider {
  
      private static final org.slf4j.Logger LOG = LoggerFactory.getLogger(SASLClientAuthProvider.class);
  
      private SaslClientState client;
      private final AuthCallbacks.GenericCallback<Void> completeCb;
  
      SASLClientAuthProvider(ClientConnectionPeer addr, AuthCallbacks.GenericCallback<Void> completeCb,
          Subject subject) {
          this.completeCb = completeCb;
          try {
              SocketAddress remoteAddr = addr.getRemoteAddr();
              String hostname;
              if (remoteAddr instanceof InetSocketAddress) {
                  InetSocketAddress inetSocketAddress = (InetSocketAddress) remoteAddr;
                  hostname = inetSocketAddress.getHostName();
              } else {
                  hostname = InetAddress.getLocalHost().getHostName();
              }
              client = new SaslClientState(hostname, subject);
              if (LOG.isDebugEnabled()) {
                  LOG.debug("SASLClientAuthProvider Boot " + client + " for " + hostname);
              }
          } catch (IOException error) {
              LOG.error("Error while booting SASL client", error);
              completeCb.operationComplete(BKException.Code.UnauthorizedAccessException, null);
          }
      }
  
      @Override
      public void init(AuthCallbacks.GenericCallback<AuthToken> cb) {
          try {
              if (client.hasInitialResponse()) {
                  byte[] response = client.evaluateChallenge(new byte[0]);
                  cb.operationComplete(BKException.Code.OK, AuthToken.wrap(response));
              } else {
                  cb.operationComplete(BKException.Code.OK, AuthToken.wrap(new byte[0]));
              }
          } catch (SaslException err) {
              LOG.error("Error on SASL client", err);
              completeCb.operationComplete(BKException.Code.UnauthorizedAccessException, null);
          }
      }
  
      @Override
      public void process(AuthToken m, AuthCallbacks.GenericCallback<AuthToken> cb) {
          if (client.isComplete()) {
              completeCb.operationComplete(BKException.Code.OK, null);
              return;
          }
          try {
              byte[] responseToken = m.getData();
              byte[] response = client.evaluateChallenge(responseToken);
              if (response == null) {
                  response = new byte[0];
              }
              cb.operationComplete(BKException.Code.OK, AuthToken.wrap(response));
              if (client.isComplete()) {
                  completeCb.operationComplete(BKException.Code.OK, null);
              }
          } catch (SaslException err) {
              LOG.error("Error on SASL client", err);
              completeCb.operationComplete(BKException.Code.UnauthorizedAccessException, null);
          }
  
      }
  
  }
  