Priyanka B | 9aaa311 | 2015-10-09 17:19:33 +0530 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 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 | package org.onosproject.bgpio.protocol.ver4; |
| 17 | |
| 18 | import org.jboss.netty.buffer.ChannelBuffer; |
| 19 | import org.onosproject.bgpio.exceptions.BGPParseException; |
| 20 | import org.onosproject.bgpio.protocol.BGPMessageReader; |
| 21 | import org.onosproject.bgpio.protocol.BGPMessageWriter; |
| 22 | import org.onosproject.bgpio.protocol.BGPNotificationMsg; |
| 23 | import org.onosproject.bgpio.protocol.BGPType; |
| 24 | import org.onosproject.bgpio.protocol.BGPVersion; |
| 25 | import org.onosproject.bgpio.types.BGPErrorType; |
| 26 | import org.onosproject.bgpio.types.BGPHeader; |
| 27 | import org.slf4j.Logger; |
| 28 | import org.slf4j.LoggerFactory; |
| 29 | |
| 30 | import com.google.common.base.MoreObjects; |
| 31 | |
| 32 | /** |
| 33 | * A NOTIFICATION message is sent when an error condition is detected. The BGP connection is closed immediately after it |
| 34 | * is sent. |
| 35 | */ |
| 36 | class BGPNotificationMsgVer4 implements BGPNotificationMsg { |
| 37 | |
| 38 | /* |
| 39 | 0 1 2 3 |
| 40 | 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 41 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 42 | | Error code | Error subcode | Data (variable) | |
| 43 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 44 | REFERENCE : RFC 4271 |
| 45 | */ |
| 46 | |
| 47 | protected static final Logger log = LoggerFactory.getLogger(BGPNotificationMsgVer4.class); |
| 48 | |
| 49 | static final byte PACKET_VERSION = 4; |
| 50 | //BGPHeader(19) + Error code(1) + Error subcode(1) |
| 51 | static final int TOTAL_MESSAGE_MIN_LENGTH = 21; |
| 52 | static final int PACKET_MINIMUM_LENGTH = 2; |
| 53 | static final BGPType MSG_TYPE = BGPType.NOTIFICATION; |
| 54 | static final byte DEFAULT_ERRORSUBCODE = 0; |
| 55 | static final byte[] MARKER = {0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, |
| 56 | 0x01, 0x01}; |
| 57 | static final byte MESSAGE_TYPE = 3; |
| 58 | static final BGPHeader DEFAULT_MESSAGE_HEADER = new BGPHeader(MARKER, BGPHeader.DEFAULT_HEADER_LENGTH, |
| 59 | MESSAGE_TYPE); |
| 60 | |
| 61 | private byte errorCode; |
| 62 | private byte errorSubCode; |
| 63 | private byte[] data; |
| 64 | private BGPHeader bgpHeader; |
| 65 | public static final BGPNotificationMsgVer4.Reader READER = new Reader(); |
| 66 | |
| 67 | /** |
| 68 | * Resets fields. |
| 69 | */ |
| 70 | public BGPNotificationMsgVer4() { |
| 71 | this.bgpHeader = null; |
| 72 | this.data = null; |
| 73 | this.errorCode = 0; |
| 74 | this.errorSubCode = 0; |
| 75 | } |
| 76 | |
| 77 | /** |
| 78 | * Constructor to initialize parameters. |
| 79 | * |
| 80 | * @param bgpHeader BGP Header in notification message |
| 81 | * @param errorCode error code |
| 82 | * @param errorSubCode error subcode |
| 83 | * @param data field |
| 84 | */ |
| 85 | public BGPNotificationMsgVer4(BGPHeader bgpHeader, byte errorCode, byte errorSubCode, byte[] data) { |
| 86 | this.bgpHeader = bgpHeader; |
| 87 | this.data = data; |
| 88 | this.errorCode = errorCode; |
| 89 | this.errorSubCode = errorSubCode; |
| 90 | } |
| 91 | |
| 92 | /** |
| 93 | * Reader reads BGP Notification Message from the channel buffer. |
| 94 | */ |
| 95 | static class Reader implements BGPMessageReader<BGPNotificationMsg> { |
| 96 | @Override |
| 97 | public BGPNotificationMsg readFrom(ChannelBuffer cb, BGPHeader bgpHeader) throws BGPParseException { |
| 98 | byte errorCode; |
| 99 | byte errorSubCode; |
| 100 | if (cb.readableBytes() < PACKET_MINIMUM_LENGTH) { |
| 101 | throw new BGPParseException("Not enough readable bytes"); |
| 102 | } |
| 103 | errorCode = cb.readByte(); |
| 104 | errorSubCode = cb.readByte(); |
| 105 | //Message Length = 21 + Data Length |
| 106 | int dataLength = bgpHeader.getLength() - TOTAL_MESSAGE_MIN_LENGTH; |
| 107 | byte[] data = new byte[dataLength]; |
| 108 | cb.readBytes(data, 0, dataLength); |
| 109 | return new BGPNotificationMsgVer4(bgpHeader, errorCode, errorSubCode, data); |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | /** |
| 114 | * Builder class for BGP notification message. |
| 115 | */ |
| 116 | static class Builder implements BGPNotificationMsg.Builder { |
| 117 | private byte errorCode; |
| 118 | private byte errorSubCode; |
| 119 | private byte[] data; |
| 120 | private BGPHeader bgpHeader; |
| 121 | private boolean isErrorCodeSet = false; |
| 122 | private boolean isErrorSubCodeSet = false; |
| 123 | private boolean isBGPHeaderSet = false; |
| 124 | |
| 125 | @Override |
Priyanka B | 9aaa311 | 2015-10-09 17:19:33 +0530 | [diff] [blame] | 126 | public BGPNotificationMsg build() throws BGPParseException { |
| 127 | BGPHeader bgpHeader = this.isBGPHeaderSet ? this.bgpHeader : DEFAULT_MESSAGE_HEADER; |
| 128 | if (!this.isErrorCodeSet) { |
| 129 | throw new BGPParseException("Error code must be present"); |
| 130 | } |
| 131 | |
| 132 | byte errorSubCode = this.isErrorSubCodeSet ? this.errorSubCode : DEFAULT_ERRORSUBCODE; |
| 133 | return new BGPNotificationMsgVer4(bgpHeader, this.errorCode, errorSubCode, this.data); |
| 134 | } |
| 135 | |
| 136 | @Override |
| 137 | public Builder setErrorCode(byte errorCode) { |
| 138 | this.errorCode = errorCode; |
| 139 | this.isErrorCodeSet = true; |
| 140 | return this; |
| 141 | } |
| 142 | |
| 143 | @Override |
| 144 | public Builder setErrorSubCode(byte errorSubCode) { |
| 145 | this.errorSubCode = errorSubCode; |
| 146 | this.isErrorSubCodeSet = true; |
| 147 | return this; |
| 148 | } |
| 149 | |
| 150 | @Override |
| 151 | public Builder setData(byte[] data) { |
| 152 | this.data = data; |
| 153 | return this; |
| 154 | } |
| 155 | |
| 156 | @Override |
| 157 | public Builder setNotificationMsgHeader(BGPHeader header) { |
| 158 | this.bgpHeader = header; |
| 159 | this.isBGPHeaderSet = true; |
| 160 | return this; |
| 161 | } |
| 162 | |
| 163 | @Override |
Priyanka B | 9aaa311 | 2015-10-09 17:19:33 +0530 | [diff] [blame] | 164 | public Builder setHeader(BGPHeader bgpMsgHeader) { |
| 165 | this.bgpHeader = bgpMsgHeader; |
| 166 | return this; |
| 167 | } |
| 168 | } |
| 169 | |
| 170 | @Override |
| 171 | public BGPVersion getVersion() { |
| 172 | return BGPVersion.BGP_4; |
| 173 | } |
| 174 | |
| 175 | @Override |
| 176 | public BGPType getType() { |
| 177 | return BGPType.NOTIFICATION; |
| 178 | } |
| 179 | |
| 180 | @Override |
| 181 | public void writeTo(ChannelBuffer cb) throws BGPParseException { |
| 182 | WRITER.write(cb, this); |
| 183 | } |
| 184 | |
| 185 | static final Writer WRITER = new Writer(); |
| 186 | |
| 187 | /** |
| 188 | * Writer writes BGP notification message to channel buffer. |
| 189 | */ |
| 190 | static class Writer implements BGPMessageWriter<BGPNotificationMsgVer4> { |
| 191 | @Override |
| 192 | public void write(ChannelBuffer cb, BGPNotificationMsgVer4 message) throws BGPParseException { |
| 193 | int msgStartIndex = cb.writerIndex(); |
| 194 | int headerLenIndex = message.bgpHeader.write(cb); |
| 195 | if (headerLenIndex <= 0) { |
| 196 | throw new BGPParseException(BGPErrorType.MESSAGE_HEADER_ERROR, (byte) 0, null); |
| 197 | } |
| 198 | cb.writeByte(message.errorCode); |
| 199 | cb.writeByte(message.errorSubCode); |
| 200 | cb.writeBytes(message.data); |
| 201 | |
| 202 | //Update message length field in notification message |
| 203 | int length = cb.writerIndex() - msgStartIndex; |
| 204 | cb.setShort(headerLenIndex, (short) length); |
| 205 | message.bgpHeader.setLength((short) length); |
| 206 | } |
| 207 | } |
| 208 | |
| 209 | @Override |
| 210 | public byte getErrorCode() { |
| 211 | return this.errorCode; |
| 212 | } |
| 213 | |
| 214 | /** |
| 215 | * Sets errorcode with specified errorcode. |
| 216 | * |
| 217 | * @param errorCode field |
| 218 | */ |
| 219 | public void setErrorCode(byte errorCode) { |
| 220 | this.errorCode = errorCode; |
| 221 | } |
| 222 | |
| 223 | @Override |
| 224 | public byte getErrorSubCode() { |
| 225 | return this.errorSubCode; |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * Sets error subcode with specified errorSubCode. |
| 230 | * |
| 231 | * @param errorSubCode field |
| 232 | */ |
| 233 | public void setErrorSubCode(byte errorSubCode) { |
| 234 | this.errorSubCode = errorSubCode; |
| 235 | } |
| 236 | |
| 237 | @Override |
| 238 | public byte[] getData() { |
| 239 | return this.data; |
| 240 | } |
| 241 | |
| 242 | /** |
| 243 | * Sets error data with specified data. |
| 244 | * |
| 245 | * @param data field |
| 246 | */ |
| 247 | public void setData(byte[] data) { |
| 248 | this.data = data; |
| 249 | } |
| 250 | |
| 251 | @Override |
| 252 | public BGPHeader getHeader() { |
| 253 | return this.bgpHeader; |
| 254 | } |
| 255 | |
| 256 | @Override |
| 257 | public String toString() { |
| 258 | return MoreObjects.toStringHelper(getClass()) |
| 259 | .omitNullValues() |
| 260 | .add("bgpHeader", bgpHeader) |
| 261 | .add("data", data) |
| 262 | .add("errorCode", errorCode) |
| 263 | .add("errorSubCode", errorSubCode) |
| 264 | .toString(); |
| 265 | } |
| 266 | } |