org.onlab.packet.UDP Maven / Gradle / Ivy
/*
* Copyright 2014-present Open Networking Foundation
*
* 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.onlab.packet;
import java.nio.ByteBuffer;
import java.util.Map;
import com.google.common.collect.ImmutableMap;
import static com.google.common.base.MoreObjects.toStringHelper;
import static org.onlab.packet.PacketUtils.*;
/**
* Representation of a UDP packet.
*/
public class UDP extends BasePacket {
public static final Map> PORT_DESERIALIZER_MAP =
ImmutableMap.>builder()
.put(UDP.DHCP_SERVER_PORT, DHCP.deserializer())
.put(UDP.DHCP_CLIENT_PORT, DHCP.deserializer())
.put(UDP.DHCP_V6_SERVER_PORT, DHCP6.deserializer())
.put(UDP.DHCP_V6_CLIENT_PORT, DHCP6.deserializer())
.put(UDP.VXLAN_UDP_PORT, VXLAN.deserializer())
.put(UDP.RIP_PORT, RIP.deserializer())
.put(UDP.RIPNG_PORT, RIPng.deserializer())
.build();
public static final int DHCP_SERVER_PORT = 67;
public static final int DHCP_CLIENT_PORT = 68;
public static final int DHCP_V6_SERVER_PORT = 547;
public static final int DHCP_V6_CLIENT_PORT = 546;
public static final int VXLAN_UDP_PORT = 4789;
public static final int RIP_PORT = 520;
public static final int RIPNG_PORT = 521;
private static final short UDP_HEADER_LENGTH = 8;
protected int sourcePort;
protected int destinationPort;
protected short length;
protected short checksum;
/**
* @return the sourcePort
*/
public int getSourcePort() {
return this.sourcePort;
}
/**
* @param sourcePort
* the sourcePort to set (16 bits unsigned integer)
* @return this
*/
public UDP setSourcePort(final int sourcePort) {
this.sourcePort = sourcePort;
return this;
}
/**
* @return the destinationPort
*/
public int getDestinationPort() {
return this.destinationPort;
}
/**
* @param destinationPort
* the destinationPort to set (16 bits unsigned integer)
* @return this
*/
public UDP setDestinationPort(final int destinationPort) {
this.destinationPort = destinationPort;
return this;
}
/**
* @return the length
*/
public short getLength() {
return this.length;
}
/**
* @return the checksum
*/
public short getChecksum() {
return this.checksum;
}
/**
* @param checksum
* the checksum to set
* @return this
*/
public UDP setChecksum(final short checksum) {
this.checksum = checksum;
return this;
}
@Override
public void resetChecksum() {
this.checksum = 0;
super.resetChecksum();
}
/**
* Serializes the packet. Will compute and set the following fields if they
* are set to specific values at the time serialize is called: -checksum : 0
* -length : 0
*/
@Override
public byte[] serialize() {
byte[] payloadData = null;
if (this.payload != null) {
this.payload.setParent(this);
payloadData = this.payload.serialize();
}
this.length = (short) (8 + (payloadData == null ? 0
: payloadData.length));
final byte[] data = new byte[this.length];
final ByteBuffer bb = ByteBuffer.wrap(data);
bb.putShort((short) (this.sourcePort & 0xffff));
bb.putShort((short) (this.destinationPort & 0xffff));
bb.putShort(this.length);
bb.putShort(this.checksum);
if (payloadData != null) {
bb.put(payloadData);
}
if (this.parent != null && this.parent instanceof IPv4) {
((IPv4) this.parent).setProtocol(IPv4.PROTOCOL_UDP);
}
// compute checksum if needed
if (this.checksum == 0) {
bb.rewind();
int accumulation = 0;
// compute pseudo header mac
if (this.parent != null) {
if (this.parent instanceof IPv4) {
final IPv4 ipv4 = (IPv4) this.parent;
accumulation += (ipv4.getSourceAddress() >> 16 & 0xffff)
+ (ipv4.getSourceAddress() & 0xffff);
accumulation += (ipv4.getDestinationAddress() >> 16 & 0xffff)
+ (ipv4.getDestinationAddress() & 0xffff);
accumulation += ipv4.getProtocol() & 0xff;
accumulation += length & 0xffff;
} else if (this.parent instanceof IPv6) {
final IPv6 ipv6 = (IPv6) this.parent;
final int bbLength =
Ip6Address.BYTE_LENGTH * 2 // IPv6 src, dst
+ 2 // nextHeader (with padding)
+ 4; // length
final ByteBuffer bbChecksum = ByteBuffer.allocate(bbLength);
bbChecksum.put(ipv6.getSourceAddress());
bbChecksum.put(ipv6.getDestinationAddress());
bbChecksum.put((byte) 0); // padding
bbChecksum.put(ipv6.getNextHeader());
bbChecksum.putInt(length);
bbChecksum.rewind();
for (int i = 0; i < bbLength / 2; ++i) {
accumulation += 0xffff & bbChecksum.getShort();
}
}
}
for (int i = 0; i < this.length / 2; ++i) {
accumulation += 0xffff & bb.getShort();
}
// pad to an even number of shorts
if (this.length % 2 > 0) {
accumulation += (bb.get() & 0xff) << 8;
}
accumulation = (accumulation >> 16 & 0xffff)
+ (accumulation & 0xffff);
this.checksum = (short) (~accumulation & 0xffff);
bb.putShort(6, this.checksum);
}
return data;
}
/*
* (non-Javadoc)
*
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
final int prime = 5807;
int result = super.hashCode();
result = prime * result + this.checksum;
result = prime * result + this.destinationPort;
result = prime * result + this.length;
result = prime * result + this.sourcePort;
return result;
}
/*
* (non-Javadoc)
*
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (!super.equals(obj)) {
return false;
}
if (!(obj instanceof UDP)) {
return false;
}
final UDP other = (UDP) obj;
if (this.checksum != other.checksum) {
return false;
}
if (this.destinationPort != other.destinationPort) {
return false;
}
if (this.length != other.length) {
return false;
}
if (this.sourcePort != other.sourcePort) {
return false;
}
return true;
}
/**
* Deserializer function for UDP packets.
*
* @return deserializer function
*/
public static Deserializer deserializer() {
return (data, offset, length) -> {
checkInput(data, offset, length, UDP_HEADER_LENGTH);
UDP udp = new UDP();
ByteBuffer bb = ByteBuffer.wrap(data, offset, length);
udp.sourcePort = (bb.getShort() & 0xffff);
udp.destinationPort = (bb.getShort() & 0xffff);
udp.length = bb.getShort();
udp.checksum = bb.getShort();
Deserializer deserializer;
if (UDP.PORT_DESERIALIZER_MAP.containsKey(udp.destinationPort)) {
deserializer = UDP.PORT_DESERIALIZER_MAP.get(udp.destinationPort);
} else if (UDP.PORT_DESERIALIZER_MAP.containsKey(udp.sourcePort)) {
deserializer = UDP.PORT_DESERIALIZER_MAP.get(udp.sourcePort);
} else {
deserializer = Data.deserializer();
}
udp.payload = deserializer.deserialize(data, bb.position(),
bb.limit() - bb.position());
udp.payload.setParent(udp);
return udp;
};
}
@Override
public String toString() {
return toStringHelper(getClass())
.add("sourcePort", Integer.toString(sourcePort))
.add("destinationPort", Integer.toString(destinationPort))
.add("length", Short.toString(length))
.add("checksum", Short.toString(checksum))
.toString();
}
}