org.nightcode.milter.command.ConnectCommandProcessor Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jmilter Show documentation
Java implementation of the Sendmail Milter protocol.
There is a newer version: 0.8
/*
 * 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 org.nightcode.milter.command;

import org.nightcode.common.util.logging.LogManager;
import org.nightcode.common.util.logging.Logger;
import org.nightcode.milter.MilterContext;
import org.nightcode.milter.MilterException;
import org.nightcode.milter.MilterHandler;
import org.nightcode.milter.MilterState;
import org.nightcode.milter.net.MilterPacket;
import org.nightcode.milter.util.MilterPacketUtil;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.nio.charset.StandardCharsets;

class ConnectCommandProcessor extends AbstractCommandHandler {

  private static final Logger LOGGER = LogManager.getLogger(ConnectCommandProcessor.class);

  public static final int SMFIA_UNKNOWN = 'U'; // Unknown (NOTE: Omits "port" and "host" fields entirely)
  public static final int SMFIA_UNIX = 'L'; // Unix (AF_UNIX/AF_LOCAL) socket ("port" is 0)
  public static final int SMFIA_INET = '4'; // TCPv4 connection
  public static final int SMFIA_INET6 = '6'; // TCPv6 connection

  private static final int LAST_ZERO_TERM_LENGTH = 1;
  private static final int PORT_OFFSET = 2;

  ConnectCommandProcessor(MilterHandler handler) {
    super(handler);
  }

  @Override public int command() {
    return SMFIC_CONNECT;
  }

  @Override public void submit(MilterContext context, MilterPacket packet) throws MilterException {
    context.setSessionState(MilterState.CONNECT);
    if (!MilterPacketUtil.isLastZeroTerm(packet.payload())) {
      LOGGER.info("[%s] received invalid packet: %s", context.id(), packet);
      handler.abortSession(context, packet);
      return;
    }

    final int payloadLength = packet.payload().length;
    int i = MilterPacketUtil.indexOfZeroTerm(packet.payload());

    if ((i + LAST_ZERO_TERM_LENGTH) >= payloadLength) {
      LOGGER.info("[%s] wrong packet length: %s", context.id(), payloadLength);
      handler.abortSession(context, packet);
      return;
    }

    int offset = 0;
    String hostname = new String(packet.payload(), offset, i, StandardCharsets.UTF_8);
    i++;

    InetAddress address = null;
    int family = packet.payload()[i++];
    if (family == SMFIA_INET) {
      if (i + PORT_OFFSET >= payloadLength) {
        LOGGER.info("[%s] wrong packet length: %s", context.id(), payloadLength);
        handler.abortSession(context, packet);
        return;
      }
      i += PORT_OFFSET;
      offset = i;
      String stringAddress = new String(packet.payload(), offset, payloadLength - offset - LAST_ZERO_TERM_LENGTH
          , StandardCharsets.UTF_8);
      try {
        address = InetAddress.getByName(stringAddress);
      } catch (UnknownHostException ex) {
        LOGGER.info("[%s] invalid address value: %s", context.id(), stringAddress);
        handler.abortSession(context, packet);
        return;
      }
    }

    handler.connect(context, hostname, address);
  }
}