/*
* Copyright 2010 NCHOVY
*
* 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.krakenapps.pcap.decoder.icmp;
import java.util.HashSet;
import java.util.Set;
import org.krakenapps.pcap.decoder.ip.Ipv4Packet;
import org.krakenapps.pcap.decoder.ip.IpProcessor;
import org.krakenapps.pcap.util.Buffer;
/**
* Decodes ICMP packet
*
* @author xeraph
*/
public class IcmpDecoder implements IpProcessor {
private Set<IcmpProcessor> callbacks = new HashSet<IcmpProcessor>();
public void register(IcmpProcessor callback) {
callbacks.add(callback);
}
public void unregister(IcmpProcessor callback) {
callbacks.remove(callback);
}
@Override
public void process(Ipv4Packet packet) {
IcmpPacket p = new IcmpPacket();
Buffer b = packet.getData();
p.setIpPacket(packet);
p.setSource(packet.getSourceAddress());
p.setDestination(packet.getDestinationAddress());
p.setType(b.get() & 0xff);
p.setCode(b.get() & 0xff);
p.setChecksum(b.getUnsignedShort());
p.setId(b.getUnsignedShort());
p.setSeq(b.getUnsignedShort());
b.discardReadBytes();
p.setData(b);
/* manipulate icmp packet from outside */
for (IcmpProcessor callback : callbacks) {
try {
callback.process(new IcmpPacket(p));
} catch (Exception e) {
e.printStackTrace();
}
}
for (IcmpProcessor callback : callbacks) {
try {
callback.process(p);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}