Thomas Vachuska | 24c849c | 2014-10-27 09:53:05 -0700 | [diff] [blame] | 1 | /* |
Thomas Vachuska | 4f1a60c | 2014-10-28 13:39:07 -0700 | [diff] [blame] | 2 | * Copyright 2014 Open Networking Laboratory |
alshabib | c4901cd | 2014-09-05 16:50:40 -0700 | [diff] [blame] | 3 | * |
Thomas Vachuska | 4f1a60c | 2014-10-28 13:39:07 -0700 | [diff] [blame] | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
alshabib | c4901cd | 2014-09-05 16:50:40 -0700 | [diff] [blame] | 7 | * |
Thomas Vachuska | 4f1a60c | 2014-10-28 13:39:07 -0700 | [diff] [blame] | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
Thomas Vachuska | 24c849c | 2014-10-27 09:53:05 -0700 | [diff] [blame] | 15 | */ |
| 16 | |
| 17 | |
alshabib | c4901cd | 2014-09-05 16:50:40 -0700 | [diff] [blame] | 18 | |
| 19 | package org.onlab.packet; |
| 20 | |
| 21 | import java.nio.ByteBuffer; |
| 22 | import java.util.HashMap; |
| 23 | import java.util.Map; |
| 24 | |
| 25 | /** |
| 26 | * |
alshabib | c4901cd | 2014-09-05 16:50:40 -0700 | [diff] [blame] | 27 | */ |
| 28 | |
| 29 | public class UDP extends BasePacket { |
| 30 | public static Map<Short, Class<? extends IPacket>> decodeMap; |
| 31 | public static final short DHCP_SERVER_PORT = (short) 67; |
| 32 | public static final short DHCP_CLIENT_PORT = (short) 68; |
| 33 | |
| 34 | static { |
| 35 | UDP.decodeMap = new HashMap<Short, Class<? extends IPacket>>(); |
| 36 | /* |
| 37 | * Disable DHCP until the deserialize code is hardened to deal with |
| 38 | * garbage input |
| 39 | */ |
| 40 | UDP.decodeMap.put(UDP.DHCP_SERVER_PORT, DHCP.class); |
| 41 | UDP.decodeMap.put(UDP.DHCP_CLIENT_PORT, DHCP.class); |
| 42 | |
| 43 | } |
| 44 | |
| 45 | protected short sourcePort; |
| 46 | protected short destinationPort; |
| 47 | protected short length; |
| 48 | protected short checksum; |
| 49 | |
| 50 | /** |
| 51 | * @return the sourcePort |
| 52 | */ |
| 53 | public short getSourcePort() { |
| 54 | return this.sourcePort; |
| 55 | } |
| 56 | |
| 57 | /** |
| 58 | * @param sourcePort |
| 59 | * the sourcePort to set |
| 60 | */ |
| 61 | public UDP setSourcePort(final short sourcePort) { |
| 62 | this.sourcePort = sourcePort; |
| 63 | return this; |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * @return the destinationPort |
| 68 | */ |
| 69 | public short getDestinationPort() { |
| 70 | return this.destinationPort; |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * @param destinationPort |
| 75 | * the destinationPort to set |
| 76 | */ |
| 77 | public UDP setDestinationPort(final short destinationPort) { |
| 78 | this.destinationPort = destinationPort; |
| 79 | return this; |
| 80 | } |
| 81 | |
| 82 | /** |
| 83 | * @return the length |
| 84 | */ |
| 85 | public short getLength() { |
| 86 | return this.length; |
| 87 | } |
| 88 | |
| 89 | /** |
| 90 | * @return the checksum |
| 91 | */ |
| 92 | public short getChecksum() { |
| 93 | return this.checksum; |
| 94 | } |
| 95 | |
| 96 | /** |
| 97 | * @param checksum |
| 98 | * the checksum to set |
| 99 | */ |
| 100 | public UDP setChecksum(final short checksum) { |
| 101 | this.checksum = checksum; |
| 102 | return this; |
| 103 | } |
| 104 | |
| 105 | @Override |
| 106 | public void resetChecksum() { |
| 107 | this.checksum = 0; |
| 108 | super.resetChecksum(); |
| 109 | } |
| 110 | |
| 111 | /** |
| 112 | * Serializes the packet. Will compute and set the following fields if they |
| 113 | * are set to specific values at the time serialize is called: -checksum : 0 |
| 114 | * -length : 0 |
| 115 | */ |
| 116 | @Override |
| 117 | public byte[] serialize() { |
| 118 | byte[] payloadData = null; |
| 119 | if (this.payload != null) { |
| 120 | this.payload.setParent(this); |
| 121 | payloadData = this.payload.serialize(); |
| 122 | } |
| 123 | |
| 124 | this.length = (short) (8 + (payloadData == null ? 0 |
| 125 | : payloadData.length)); |
| 126 | |
| 127 | final byte[] data = new byte[this.length]; |
| 128 | final ByteBuffer bb = ByteBuffer.wrap(data); |
| 129 | |
| 130 | bb.putShort(this.sourcePort); |
| 131 | bb.putShort(this.destinationPort); |
| 132 | bb.putShort(this.length); |
| 133 | bb.putShort(this.checksum); |
| 134 | if (payloadData != null) { |
| 135 | bb.put(payloadData); |
| 136 | } |
| 137 | |
| 138 | if (this.parent != null && this.parent instanceof IPv4) { |
| 139 | ((IPv4) this.parent).setProtocol(IPv4.PROTOCOL_UDP); |
| 140 | } |
| 141 | |
| 142 | // compute checksum if needed |
| 143 | if (this.checksum == 0) { |
| 144 | bb.rewind(); |
| 145 | int accumulation = 0; |
| 146 | |
| 147 | // compute pseudo header mac |
| 148 | if (this.parent != null && this.parent instanceof IPv4) { |
| 149 | final IPv4 ipv4 = (IPv4) this.parent; |
| 150 | accumulation += (ipv4.getSourceAddress() >> 16 & 0xffff) |
| 151 | + (ipv4.getSourceAddress() & 0xffff); |
| 152 | accumulation += (ipv4.getDestinationAddress() >> 16 & 0xffff) |
| 153 | + (ipv4.getDestinationAddress() & 0xffff); |
| 154 | accumulation += ipv4.getProtocol() & 0xff; |
| 155 | accumulation += this.length & 0xffff; |
| 156 | } |
| 157 | |
| 158 | for (int i = 0; i < this.length / 2; ++i) { |
| 159 | accumulation += 0xffff & bb.getShort(); |
| 160 | } |
| 161 | // pad to an even number of shorts |
| 162 | if (this.length % 2 > 0) { |
| 163 | accumulation += (bb.get() & 0xff) << 8; |
| 164 | } |
| 165 | |
| 166 | accumulation = (accumulation >> 16 & 0xffff) |
| 167 | + (accumulation & 0xffff); |
| 168 | this.checksum = (short) (~accumulation & 0xffff); |
| 169 | bb.putShort(6, this.checksum); |
| 170 | } |
| 171 | return data; |
| 172 | } |
| 173 | |
| 174 | /* |
| 175 | * (non-Javadoc) |
| 176 | * |
| 177 | * @see java.lang.Object#hashCode() |
| 178 | */ |
| 179 | @Override |
| 180 | public int hashCode() { |
| 181 | final int prime = 5807; |
| 182 | int result = super.hashCode(); |
| 183 | result = prime * result + this.checksum; |
| 184 | result = prime * result + this.destinationPort; |
| 185 | result = prime * result + this.length; |
| 186 | result = prime * result + this.sourcePort; |
| 187 | return result; |
| 188 | } |
| 189 | |
| 190 | /* |
| 191 | * (non-Javadoc) |
| 192 | * |
| 193 | * @see java.lang.Object#equals(java.lang.Object) |
| 194 | */ |
| 195 | @Override |
| 196 | public boolean equals(final Object obj) { |
| 197 | if (this == obj) { |
| 198 | return true; |
| 199 | } |
| 200 | if (!super.equals(obj)) { |
| 201 | return false; |
| 202 | } |
| 203 | if (!(obj instanceof UDP)) { |
| 204 | return false; |
| 205 | } |
| 206 | final UDP other = (UDP) obj; |
| 207 | if (this.checksum != other.checksum) { |
| 208 | return false; |
| 209 | } |
| 210 | if (this.destinationPort != other.destinationPort) { |
| 211 | return false; |
| 212 | } |
| 213 | if (this.length != other.length) { |
| 214 | return false; |
| 215 | } |
| 216 | if (this.sourcePort != other.sourcePort) { |
| 217 | return false; |
| 218 | } |
| 219 | return true; |
| 220 | } |
| 221 | |
| 222 | @Override |
| 223 | public IPacket deserialize(final byte[] data, final int offset, |
| 224 | final int length) { |
| 225 | final ByteBuffer bb = ByteBuffer.wrap(data, offset, length); |
| 226 | this.sourcePort = bb.getShort(); |
| 227 | this.destinationPort = bb.getShort(); |
| 228 | this.length = bb.getShort(); |
| 229 | this.checksum = bb.getShort(); |
| 230 | |
| 231 | if (UDP.decodeMap.containsKey(this.destinationPort)) { |
| 232 | try { |
| 233 | this.payload = UDP.decodeMap.get(this.destinationPort) |
| 234 | .getConstructor().newInstance(); |
| 235 | } catch (final Exception e) { |
| 236 | throw new RuntimeException("Failure instantiating class", e); |
| 237 | } |
| 238 | } else if (UDP.decodeMap.containsKey(this.sourcePort)) { |
| 239 | try { |
| 240 | this.payload = UDP.decodeMap.get(this.sourcePort) |
| 241 | .getConstructor().newInstance(); |
| 242 | } catch (final Exception e) { |
| 243 | throw new RuntimeException("Failure instantiating class", e); |
| 244 | } |
| 245 | } else { |
| 246 | this.payload = new Data(); |
| 247 | } |
| 248 | this.payload = this.payload.deserialize(data, bb.position(), bb.limit() |
| 249 | - bb.position()); |
| 250 | this.payload.setParent(this); |
| 251 | return this; |
| 252 | } |
| 253 | } |