Charles M.C. Chan | 94f3737 | 2015-01-10 17:53:42 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2014-2015 Open Networking Laboratory |
| 3 | * |
| 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 |
| 7 | * |
| 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. |
| 15 | */ |
| 16 | |
| 17 | package org.onlab.packet.ipv6; |
| 18 | |
| 19 | import org.onlab.packet.BasePacket; |
| 20 | import org.onlab.packet.Data; |
| 21 | import org.onlab.packet.IPacket; |
| 22 | import org.onlab.packet.IPv6; |
| 23 | |
| 24 | import java.nio.ByteBuffer; |
| 25 | |
| 26 | /** |
| 27 | * Implements IPv6 fragment extension header format. (RFC 2460) |
| 28 | */ |
| 29 | public class Fragment extends BasePacket implements IExtensionHeader { |
| 30 | public static final byte HEADER_LENGTH = 8; // bytes |
| 31 | |
| 32 | protected byte nextHeader; |
| 33 | protected short fragmentOffset; |
| 34 | protected byte moreFragment; |
| 35 | protected int identification; |
| 36 | |
| 37 | @Override |
| 38 | public byte getNextHeader() { |
| 39 | return this.nextHeader; |
| 40 | } |
| 41 | |
| 42 | @Override |
| 43 | public Fragment setNextHeader(final byte nextHeader) { |
| 44 | this.nextHeader = nextHeader; |
| 45 | return this; |
| 46 | } |
| 47 | |
| 48 | /** |
| 49 | * Gets the fragment offset of this header. |
| 50 | * |
| 51 | * @return fragment offset |
| 52 | */ |
| 53 | public short getFragmentOffset() { |
| 54 | return this.fragmentOffset; |
| 55 | } |
| 56 | |
| 57 | /** |
| 58 | * Sets the fragment offset of this header. |
| 59 | * |
| 60 | * @param fragmentOffset the fragment offset to set |
| 61 | * @return this |
| 62 | */ |
| 63 | public Fragment setFragmentOffset(final short fragmentOffset) { |
| 64 | this.fragmentOffset = fragmentOffset; |
| 65 | return this; |
| 66 | } |
| 67 | |
| 68 | /** |
| 69 | * Gets the more fragment flag of this header. |
| 70 | * |
| 71 | * @return more fragment flag |
| 72 | */ |
| 73 | public byte getMoreFragment() { |
| 74 | return this.moreFragment; |
| 75 | } |
| 76 | |
| 77 | /** |
| 78 | * Sets the more fragment flag of this header. |
| 79 | * |
| 80 | * @param moreFragment the more fragment flag to set |
| 81 | * @return this |
| 82 | */ |
| 83 | public Fragment setMoreFragment(final byte moreFragment) { |
| 84 | this.moreFragment = moreFragment; |
| 85 | return this; |
| 86 | } |
| 87 | |
| 88 | /** |
| 89 | * Gets the identification of this header. |
| 90 | * |
| 91 | * @return identification |
| 92 | */ |
| 93 | public int getIdentification() { |
| 94 | return this.identification; |
| 95 | } |
| 96 | |
| 97 | /** |
| 98 | * Sets the identification of this header. |
| 99 | * |
| 100 | * @param identification the identification to set |
| 101 | * @return this |
| 102 | */ |
| 103 | public Fragment setIdentification(final int identification) { |
| 104 | this.identification = identification; |
| 105 | return this; |
| 106 | } |
| 107 | |
| 108 | @Override |
| 109 | public byte[] serialize() { |
| 110 | byte[] payloadData = null; |
| 111 | if (this.payload != null) { |
| 112 | this.payload.setParent(this); |
| 113 | payloadData = this.payload.serialize(); |
| 114 | } |
| 115 | |
| 116 | int payloadLength = 0; |
| 117 | if (payloadData != null) { |
| 118 | payloadLength = payloadData.length; |
| 119 | } |
| 120 | |
| 121 | final byte[] data = new byte[HEADER_LENGTH + payloadLength]; |
| 122 | final ByteBuffer bb = ByteBuffer.wrap(data); |
| 123 | |
| 124 | bb.put(this.nextHeader); |
| 125 | bb.put((byte) 0); |
| 126 | bb.putShort((short) ( |
| 127 | (this.fragmentOffset & 0x1fff) << 3 | |
| 128 | this.moreFragment & 0x1 |
| 129 | )); |
| 130 | bb.putInt(this.identification); |
| 131 | |
| 132 | if (payloadData != null) { |
| 133 | bb.put(payloadData); |
| 134 | } |
| 135 | |
| 136 | if (this.parent != null && this.parent instanceof IExtensionHeader) { |
| 137 | ((IExtensionHeader) this.parent).setNextHeader(IPv6.PROTOCOL_FRAG); |
| 138 | } |
| 139 | return data; |
| 140 | } |
| 141 | |
| 142 | @Override |
| 143 | public IPacket deserialize(byte[] data, int offset, int length) { |
| 144 | final ByteBuffer bb = ByteBuffer.wrap(data, offset, length); |
| 145 | this.nextHeader = bb.get(); |
| 146 | bb.get(); |
| 147 | short sscratch = bb.getShort(); |
| 148 | this.fragmentOffset = (short) (sscratch >> 3 & 0x1fff); |
| 149 | this.moreFragment = (byte) (sscratch & 0x1); |
| 150 | this.identification = bb.getInt(); |
| 151 | |
| 152 | IPacket payload; |
| 153 | if (IPv6.PROTOCOL_CLASS_MAP.containsKey(this.nextHeader)) { |
| 154 | final Class<? extends IPacket> clazz = IPv6.PROTOCOL_CLASS_MAP |
| 155 | .get(this.nextHeader); |
| 156 | try { |
| 157 | payload = clazz.newInstance(); |
| 158 | } catch (final Exception e) { |
| 159 | throw new RuntimeException( |
| 160 | "Error parsing payload for Fragment packet", e); |
| 161 | } |
| 162 | } else { |
| 163 | payload = new Data(); |
| 164 | } |
| 165 | this.payload = payload.deserialize(data, bb.position(), |
| 166 | bb.limit() - bb.position()); |
| 167 | this.payload.setParent(this); |
| 168 | |
| 169 | return this; |
| 170 | } |
| 171 | |
| 172 | /* |
| 173 | * (non-Javadoc) |
| 174 | * |
| 175 | * @see java.lang.Object#hashCode() |
| 176 | */ |
| 177 | @Override |
| 178 | public int hashCode() { |
| 179 | final int prime = 5807; |
| 180 | int result = super.hashCode(); |
| 181 | result = prime * result + this.nextHeader; |
| 182 | result = prime * result + this.fragmentOffset; |
| 183 | result = prime * result + this.moreFragment; |
| 184 | result = prime * result + this.identification; |
| 185 | return result; |
| 186 | } |
| 187 | |
| 188 | /* |
| 189 | * (non-Javadoc) |
| 190 | * |
| 191 | * @see java.lang.Object#equals(java.lang.Object) |
| 192 | */ |
| 193 | @Override |
| 194 | public boolean equals(final Object obj) { |
| 195 | if (this == obj) { |
| 196 | return true; |
| 197 | } |
| 198 | if (!super.equals(obj)) { |
| 199 | return false; |
| 200 | } |
| 201 | if (!(obj instanceof Fragment)) { |
| 202 | return false; |
| 203 | } |
| 204 | final Fragment other = (Fragment) obj; |
| 205 | if (this.nextHeader != other.nextHeader) { |
| 206 | return false; |
| 207 | } |
| 208 | if (this.fragmentOffset != other.fragmentOffset) { |
| 209 | return false; |
| 210 | } |
| 211 | if (this.moreFragment != other.moreFragment) { |
| 212 | return false; |
| 213 | } |
| 214 | if (this.identification != other.identification) { |
| 215 | return false; |
| 216 | } |
| 217 | return true; |
| 218 | } |
| 219 | } |