| /* |
| * 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.HashMap; |
| import java.util.Map; |
| |
| 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<Integer, Deserializer<? extends IPacket>> PORT_DESERIALIZER_MAP = |
| new HashMap<>(); |
| public static final int DHCP_SERVER_PORT = 67; |
| public static final int DHCP_CLIENT_PORT = 68; |
| |
| private static final short UDP_HEADER_LENGTH = 8; |
| |
| static { |
| /* |
| * Disable DHCP until the deserialize code is hardened to deal with |
| * garbage input |
| */ |
| UDP.PORT_DESERIALIZER_MAP.put(UDP.DHCP_SERVER_PORT, DHCP.deserializer()); |
| UDP.PORT_DESERIALIZER_MAP.put(UDP.DHCP_CLIENT_PORT, DHCP.deserializer()); |
| |
| } |
| |
| 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; |
| } |
| |
| @Override |
| public IPacket deserialize(final byte[] data, final int offset, |
| final int length) { |
| final ByteBuffer bb = ByteBuffer.wrap(data, offset, length); |
| this.sourcePort = (bb.getShort() & 0xffff); |
| this.destinationPort = (bb.getShort() & 0xffff); |
| this.length = bb.getShort(); |
| this.checksum = bb.getShort(); |
| |
| Deserializer<? extends IPacket> deserializer; |
| if (UDP.PORT_DESERIALIZER_MAP.containsKey(this.destinationPort)) { |
| deserializer = UDP.PORT_DESERIALIZER_MAP.get(this.destinationPort); |
| } else if (UDP.PORT_DESERIALIZER_MAP.containsKey(this.sourcePort)) { |
| deserializer = UDP.PORT_DESERIALIZER_MAP.get(this.sourcePort); |
| } else { |
| deserializer = Data.deserializer(); |
| } |
| |
| try { |
| this.payload = deserializer.deserialize(data, bb.position(), |
| bb.limit() - bb.position()); |
| this.payload.setParent(this); |
| } catch (DeserializationException e) { |
| return this; |
| } |
| return this; |
| } |
| |
| /* |
| * (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<UDP> 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<? extends IPacket> 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(); |
| } |
| } |