Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2014 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.sdnip.bgp; |
| 17 | |
| 18 | import java.util.ArrayList; |
| 19 | import java.util.Collection; |
| 20 | import java.util.HashMap; |
| 21 | import java.util.Map; |
| 22 | |
| 23 | import org.apache.commons.lang3.tuple.Pair; |
| 24 | import org.jboss.netty.buffer.ChannelBuffer; |
| 25 | import org.jboss.netty.buffer.ChannelBuffers; |
| 26 | import org.jboss.netty.channel.ChannelHandlerContext; |
| 27 | import org.onlab.packet.Ip4Address; |
| 28 | import org.onlab.packet.Ip4Prefix; |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 29 | import org.onlab.packet.Ip6Address; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 30 | import org.onlab.packet.Ip6Prefix; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 31 | import org.onosproject.sdnip.bgp.BgpConstants.Notifications.UpdateMessageError; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 32 | import org.onosproject.sdnip.bgp.BgpConstants.Open.Capabilities.MultiprotocolExtensions; |
| 33 | import org.onosproject.sdnip.bgp.BgpConstants.Update; |
| 34 | import org.onosproject.sdnip.bgp.BgpConstants.Update.AsPath; |
Pavlin Radoslavov | 278cdde | 2014-12-16 14:09:31 -0800 | [diff] [blame] | 35 | import org.onosproject.sdnip.bgp.BgpMessage.BgpParseException; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 36 | import org.slf4j.Logger; |
| 37 | import org.slf4j.LoggerFactory; |
| 38 | |
| 39 | /** |
| 40 | * A class for handling BGP UPDATE messages. |
| 41 | */ |
| 42 | final class BgpUpdate { |
| 43 | private static final Logger log = LoggerFactory.getLogger(BgpUpdate.class); |
| 44 | |
| 45 | /** |
| 46 | * Default constructor. |
| 47 | * <p> |
| 48 | * The constructor is private to prevent creating an instance of |
| 49 | * this utility class. |
| 50 | */ |
| 51 | private BgpUpdate() { |
| 52 | } |
| 53 | |
| 54 | /** |
| 55 | * Processes BGP UPDATE message. |
| 56 | * |
| 57 | * @param bgpSession the BGP Session to use |
| 58 | * @param ctx the Channel Handler Context |
| 59 | * @param message the message to process |
| 60 | */ |
| 61 | static void processBgpUpdate(BgpSession bgpSession, |
| 62 | ChannelHandlerContext ctx, |
| 63 | ChannelBuffer message) { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 64 | DecodedBgpRoutes decodedBgpRoutes = new DecodedBgpRoutes(); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 65 | |
| 66 | int minLength = |
| 67 | BgpConstants.BGP_UPDATE_MIN_LENGTH - BgpConstants.BGP_HEADER_LENGTH; |
| 68 | if (message.readableBytes() < minLength) { |
| 69 | log.debug("BGP RX UPDATE Error from {}: " + |
| 70 | "Message length {} too short. Must be at least {}", |
| 71 | bgpSession.getRemoteAddress(), message.readableBytes(), |
| 72 | minLength); |
| 73 | // |
| 74 | // ERROR: Bad Message Length |
| 75 | // |
| 76 | // Send NOTIFICATION and close the connection |
| 77 | ChannelBuffer txMessage = |
| 78 | BgpNotification.prepareBgpNotificationBadMessageLength( |
| 79 | message.readableBytes() + BgpConstants.BGP_HEADER_LENGTH); |
| 80 | ctx.getChannel().write(txMessage); |
| 81 | bgpSession.closeSession(ctx); |
| 82 | return; |
| 83 | } |
| 84 | |
| 85 | log.debug("BGP RX UPDATE message from {}", |
| 86 | bgpSession.getRemoteAddress()); |
| 87 | |
| 88 | // |
| 89 | // Parse the UPDATE message |
| 90 | // |
| 91 | |
| 92 | // |
| 93 | // Parse the Withdrawn Routes |
| 94 | // |
| 95 | int withdrawnRoutesLength = message.readUnsignedShort(); |
| 96 | if (withdrawnRoutesLength > message.readableBytes()) { |
| 97 | // ERROR: Malformed Attribute List |
| 98 | actionsBgpUpdateMalformedAttributeList(bgpSession, ctx); |
| 99 | return; |
| 100 | } |
| 101 | Collection<Ip4Prefix> withdrawnPrefixes = null; |
| 102 | try { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 103 | withdrawnPrefixes = parsePackedIp4Prefixes(withdrawnRoutesLength, |
| 104 | message); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 105 | } catch (BgpParseException e) { |
| 106 | // ERROR: Invalid Network Field |
| 107 | log.debug("Exception parsing Withdrawn Prefixes from BGP peer {}: ", |
| 108 | bgpSession.getRemoteBgpId(), e); |
| 109 | actionsBgpUpdateInvalidNetworkField(bgpSession, ctx); |
| 110 | return; |
| 111 | } |
| 112 | for (Ip4Prefix prefix : withdrawnPrefixes) { |
| 113 | log.debug("BGP RX UPDATE message WITHDRAWN from {}: {}", |
| 114 | bgpSession.getRemoteAddress(), prefix); |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 115 | BgpRouteEntry bgpRouteEntry = bgpSession.findBgpRoute(prefix); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 116 | if (bgpRouteEntry != null) { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 117 | decodedBgpRoutes.deletedUnicastRoutes4.put(prefix, |
| 118 | bgpRouteEntry); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 119 | } |
| 120 | } |
| 121 | |
| 122 | // |
| 123 | // Parse the Path Attributes |
| 124 | // |
| 125 | try { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 126 | parsePathAttributes(bgpSession, ctx, message, decodedBgpRoutes); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 127 | } catch (BgpParseException e) { |
| 128 | log.debug("Exception parsing Path Attributes from BGP peer {}: ", |
| 129 | bgpSession.getRemoteBgpId(), e); |
| 130 | // NOTE: The session was already closed, so nothing else to do |
| 131 | return; |
| 132 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 133 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 134 | // |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 135 | // Update the BGP RIB-IN |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 136 | // |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 137 | for (Ip4Prefix ip4Prefix : |
| 138 | decodedBgpRoutes.deletedUnicastRoutes4.keySet()) { |
| 139 | bgpSession.removeBgpRoute(ip4Prefix); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 140 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 141 | // |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 142 | for (BgpRouteEntry bgpRouteEntry : |
| 143 | decodedBgpRoutes.addedUnicastRoutes4.values()) { |
| 144 | bgpSession.addBgpRoute(bgpRouteEntry); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 145 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 146 | // |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 147 | for (Ip6Prefix ip6Prefix : |
| 148 | decodedBgpRoutes.deletedUnicastRoutes6.keySet()) { |
| 149 | bgpSession.removeBgpRoute(ip6Prefix); |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 150 | } |
| 151 | // |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 152 | for (BgpRouteEntry bgpRouteEntry : |
| 153 | decodedBgpRoutes.addedUnicastRoutes6.values()) { |
| 154 | bgpSession.addBgpRoute(bgpRouteEntry); |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 155 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 156 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 157 | // |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 158 | // Push the updates to the BGP Merged RIB |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 159 | // |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 160 | BgpRouteSelector bgpRouteSelector = |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 161 | bgpSession.getBgpSessionManager().getBgpRouteSelector(); |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 162 | bgpRouteSelector.routeUpdates(bgpSession, |
| 163 | decodedBgpRoutes.addedUnicastRoutes4.values(), |
| 164 | decodedBgpRoutes.deletedUnicastRoutes4.values()); |
| 165 | bgpRouteSelector.routeUpdates(bgpSession, |
| 166 | decodedBgpRoutes.addedUnicastRoutes6.values(), |
| 167 | decodedBgpRoutes.deletedUnicastRoutes6.values()); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 168 | |
| 169 | // Start the Session Timeout timer |
| 170 | bgpSession.restartSessionTimeoutTimer(ctx); |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * Parse BGP Path Attributes from the BGP UPDATE message. |
| 175 | * |
| 176 | * @param bgpSession the BGP Session to use |
| 177 | * @param ctx the Channel Handler Context |
| 178 | * @param message the message to parse |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 179 | * @param decodedBgpRoutes the container to store the decoded BGP Route |
| 180 | * Entries. It might already contain some route entries such as withdrawn |
| 181 | * IPv4 prefixes |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 182 | * @throws BgpParseException |
| 183 | */ |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 184 | // CHECKSTYLE IGNORE MethodLength FOR NEXT 300 LINES |
| 185 | private static void parsePathAttributes( |
| 186 | BgpSession bgpSession, |
| 187 | ChannelHandlerContext ctx, |
| 188 | ChannelBuffer message, |
| 189 | DecodedBgpRoutes decodedBgpRoutes) |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 190 | throws BgpParseException { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 191 | |
| 192 | // |
| 193 | // Parsed values |
| 194 | // |
| 195 | Short origin = -1; // Mandatory |
| 196 | BgpRouteEntry.AsPath asPath = null; // Mandatory |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 197 | // Legacy NLRI (RFC 4271). Mandatory NEXT_HOP if legacy NLRI is used |
| 198 | MpNlri legacyNlri = new MpNlri(MultiprotocolExtensions.AFI_IPV4, |
| 199 | MultiprotocolExtensions.SAFI_UNICAST); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 200 | long multiExitDisc = // Optional |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 201 | Update.MultiExitDisc.LOWEST_MULTI_EXIT_DISC; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 202 | Long localPref = null; // Mandatory |
| 203 | Long aggregatorAsNumber = null; // Optional: unused |
| 204 | Ip4Address aggregatorIpAddress = null; // Optional: unused |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 205 | Collection<MpNlri> mpNlriReachList = new ArrayList<>(); // Optional |
| 206 | Collection<MpNlri> mpNlriUnreachList = new ArrayList<>(); // Optional |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 207 | |
| 208 | // |
| 209 | // Get and verify the Path Attributes Length |
| 210 | // |
| 211 | int pathAttributeLength = message.readUnsignedShort(); |
| 212 | if (pathAttributeLength > message.readableBytes()) { |
| 213 | // ERROR: Malformed Attribute List |
| 214 | actionsBgpUpdateMalformedAttributeList(bgpSession, ctx); |
| 215 | String errorMsg = "Malformed Attribute List"; |
| 216 | throw new BgpParseException(errorMsg); |
| 217 | } |
| 218 | if (pathAttributeLength == 0) { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 219 | return; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 220 | } |
| 221 | |
| 222 | // |
| 223 | // Parse the Path Attributes |
| 224 | // |
| 225 | int pathAttributeEnd = message.readerIndex() + pathAttributeLength; |
| 226 | while (message.readerIndex() < pathAttributeEnd) { |
| 227 | int attrFlags = message.readUnsignedByte(); |
| 228 | if (message.readerIndex() >= pathAttributeEnd) { |
| 229 | // ERROR: Malformed Attribute List |
| 230 | actionsBgpUpdateMalformedAttributeList(bgpSession, ctx); |
| 231 | String errorMsg = "Malformed Attribute List"; |
| 232 | throw new BgpParseException(errorMsg); |
| 233 | } |
| 234 | int attrTypeCode = message.readUnsignedByte(); |
| 235 | |
| 236 | // The Attribute Flags |
| 237 | boolean optionalBit = ((0x80 & attrFlags) != 0); |
| 238 | boolean transitiveBit = ((0x40 & attrFlags) != 0); |
| 239 | boolean partialBit = ((0x20 & attrFlags) != 0); |
| 240 | boolean extendedLengthBit = ((0x10 & attrFlags) != 0); |
| 241 | |
| 242 | // The Attribute Length |
| 243 | int attrLen = 0; |
| 244 | int attrLenOctets = 1; |
| 245 | if (extendedLengthBit) { |
| 246 | attrLenOctets = 2; |
| 247 | } |
| 248 | if (message.readerIndex() + attrLenOctets > pathAttributeEnd) { |
| 249 | // ERROR: Malformed Attribute List |
| 250 | actionsBgpUpdateMalformedAttributeList(bgpSession, ctx); |
| 251 | String errorMsg = "Malformed Attribute List"; |
| 252 | throw new BgpParseException(errorMsg); |
| 253 | } |
| 254 | if (extendedLengthBit) { |
| 255 | attrLen = message.readUnsignedShort(); |
| 256 | } else { |
| 257 | attrLen = message.readUnsignedByte(); |
| 258 | } |
| 259 | if (message.readerIndex() + attrLen > pathAttributeEnd) { |
| 260 | // ERROR: Malformed Attribute List |
| 261 | actionsBgpUpdateMalformedAttributeList(bgpSession, ctx); |
| 262 | String errorMsg = "Malformed Attribute List"; |
| 263 | throw new BgpParseException(errorMsg); |
| 264 | } |
| 265 | |
| 266 | // Verify the Attribute Flags |
| 267 | verifyBgpUpdateAttributeFlags(bgpSession, ctx, attrTypeCode, |
| 268 | attrLen, attrFlags, message); |
| 269 | |
| 270 | // |
| 271 | // Extract the Attribute Value based on the Attribute Type Code |
| 272 | // |
| 273 | switch (attrTypeCode) { |
| 274 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 275 | case Update.Origin.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 276 | // Attribute Type Code ORIGIN |
| 277 | origin = parseAttributeTypeOrigin(bgpSession, ctx, |
| 278 | attrTypeCode, attrLen, |
| 279 | attrFlags, message); |
| 280 | break; |
| 281 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 282 | case Update.AsPath.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 283 | // Attribute Type Code AS_PATH |
| 284 | asPath = parseAttributeTypeAsPath(bgpSession, ctx, |
| 285 | attrTypeCode, attrLen, |
| 286 | attrFlags, message); |
| 287 | break; |
| 288 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 289 | case Update.NextHop.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 290 | // Attribute Type Code NEXT_HOP |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 291 | legacyNlri.nextHop4 = |
| 292 | parseAttributeTypeNextHop(bgpSession, ctx, |
| 293 | attrTypeCode, attrLen, |
| 294 | attrFlags, message); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 295 | break; |
| 296 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 297 | case Update.MultiExitDisc.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 298 | // Attribute Type Code MULTI_EXIT_DISC |
| 299 | multiExitDisc = |
| 300 | parseAttributeTypeMultiExitDisc(bgpSession, ctx, |
| 301 | attrTypeCode, attrLen, |
| 302 | attrFlags, message); |
| 303 | break; |
| 304 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 305 | case Update.LocalPref.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 306 | // Attribute Type Code LOCAL_PREF |
| 307 | localPref = |
| 308 | parseAttributeTypeLocalPref(bgpSession, ctx, |
| 309 | attrTypeCode, attrLen, |
| 310 | attrFlags, message); |
| 311 | break; |
| 312 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 313 | case Update.AtomicAggregate.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 314 | // Attribute Type Code ATOMIC_AGGREGATE |
| 315 | parseAttributeTypeAtomicAggregate(bgpSession, ctx, |
| 316 | attrTypeCode, attrLen, |
| 317 | attrFlags, message); |
| 318 | // Nothing to do: this attribute is primarily informational |
| 319 | break; |
| 320 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 321 | case Update.Aggregator.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 322 | // Attribute Type Code AGGREGATOR |
| 323 | Pair<Long, Ip4Address> aggregator = |
| 324 | parseAttributeTypeAggregator(bgpSession, ctx, |
| 325 | attrTypeCode, attrLen, |
| 326 | attrFlags, message); |
| 327 | aggregatorAsNumber = aggregator.getLeft(); |
| 328 | aggregatorIpAddress = aggregator.getRight(); |
| 329 | break; |
| 330 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 331 | case Update.MpReachNlri.TYPE: |
| 332 | // Attribute Type Code MP_REACH_NLRI |
| 333 | MpNlri mpNlriReach = |
| 334 | parseAttributeTypeMpReachNlri(bgpSession, ctx, |
| 335 | attrTypeCode, |
| 336 | attrLen, |
| 337 | attrFlags, message); |
| 338 | if (mpNlriReach != null) { |
| 339 | mpNlriReachList.add(mpNlriReach); |
| 340 | } |
| 341 | break; |
| 342 | |
| 343 | case Update.MpUnreachNlri.TYPE: |
| 344 | // Attribute Type Code MP_UNREACH_NLRI |
| 345 | MpNlri mpNlriUnreach = |
| 346 | parseAttributeTypeMpUnreachNlri(bgpSession, ctx, |
| 347 | attrTypeCode, attrLen, |
| 348 | attrFlags, message); |
| 349 | if (mpNlriUnreach != null) { |
| 350 | mpNlriUnreachList.add(mpNlriUnreach); |
| 351 | } |
| 352 | break; |
| 353 | |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 354 | default: |
| 355 | // NOTE: Parse any new Attribute Types if needed |
| 356 | if (!optionalBit) { |
| 357 | // ERROR: Unrecognized Well-known Attribute |
| 358 | actionsBgpUpdateUnrecognizedWellKnownAttribute( |
| 359 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, |
| 360 | message); |
| 361 | String errorMsg = "Unrecognized Well-known Attribute: " + |
| 362 | attrTypeCode; |
| 363 | throw new BgpParseException(errorMsg); |
| 364 | } |
| 365 | |
| 366 | // Skip the data from the unrecognized attribute |
| 367 | log.debug("BGP RX UPDATE message from {}: " + |
| 368 | "Unrecognized Attribute Type {}", |
| 369 | bgpSession.getRemoteAddress(), attrTypeCode); |
| 370 | message.skipBytes(attrLen); |
| 371 | break; |
| 372 | } |
| 373 | } |
| 374 | |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 375 | // |
| 376 | // Parse the NLRI (Network Layer Reachability Information) |
| 377 | // |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 378 | int nlriLength = message.readableBytes(); |
| 379 | try { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 380 | Collection<Ip4Prefix> addedPrefixes4 = |
| 381 | parsePackedIp4Prefixes(nlriLength, message); |
| 382 | // Store it inside the legacy NLRI wrapper |
| 383 | legacyNlri.nlri4 = addedPrefixes4; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 384 | } catch (BgpParseException e) { |
| 385 | // ERROR: Invalid Network Field |
| 386 | log.debug("Exception parsing NLRI from BGP peer {}: ", |
| 387 | bgpSession.getRemoteBgpId(), e); |
| 388 | actionsBgpUpdateInvalidNetworkField(bgpSession, ctx); |
| 389 | // Rethrow the exception |
| 390 | throw e; |
| 391 | } |
| 392 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 393 | // Verify the Well-known Attributes |
| 394 | verifyBgpUpdateWellKnownAttributes(bgpSession, ctx, origin, asPath, |
| 395 | localPref, legacyNlri, |
| 396 | mpNlriReachList); |
| 397 | |
| 398 | // |
| 399 | // Generate the deleted routes |
| 400 | // |
| 401 | for (MpNlri mpNlri : mpNlriUnreachList) { |
| 402 | BgpRouteEntry bgpRouteEntry; |
| 403 | |
| 404 | // The deleted IPv4 routes |
| 405 | for (Ip4Prefix prefix : mpNlri.nlri4) { |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 406 | bgpRouteEntry = bgpSession.findBgpRoute(prefix); |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 407 | if (bgpRouteEntry != null) { |
| 408 | decodedBgpRoutes.deletedUnicastRoutes4.put(prefix, |
| 409 | bgpRouteEntry); |
| 410 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 411 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 412 | |
| 413 | // The deleted IPv6 routes |
| 414 | for (Ip6Prefix prefix : mpNlri.nlri6) { |
Pavlin Radoslavov | 3a0a52e | 2015-01-06 17:41:37 -0800 | [diff] [blame] | 415 | bgpRouteEntry = bgpSession.findBgpRoute(prefix); |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 416 | if (bgpRouteEntry != null) { |
| 417 | decodedBgpRoutes.deletedUnicastRoutes6.put(prefix, |
| 418 | bgpRouteEntry); |
| 419 | } |
| 420 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 421 | } |
| 422 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 423 | // |
| 424 | // Generate the added routes |
| 425 | // |
| 426 | mpNlriReachList.add(legacyNlri); |
| 427 | for (MpNlri mpNlri : mpNlriReachList) { |
| 428 | BgpRouteEntry bgpRouteEntry; |
| 429 | |
| 430 | // The added IPv4 routes |
| 431 | for (Ip4Prefix prefix : mpNlri.nlri4) { |
| 432 | bgpRouteEntry = |
| 433 | new BgpRouteEntry(bgpSession, prefix, mpNlri.nextHop4, |
| 434 | origin.byteValue(), asPath, localPref); |
| 435 | bgpRouteEntry.setMultiExitDisc(multiExitDisc); |
| 436 | if (bgpRouteEntry.hasAsPathLoop(bgpSession.getLocalAs())) { |
| 437 | log.debug("BGP RX UPDATE message IGNORED from {}: {} " + |
| 438 | "nextHop {}: contains AS Path loop", |
| 439 | bgpSession.getRemoteAddress(), prefix, |
| 440 | mpNlri.nextHop4); |
| 441 | continue; |
| 442 | } else { |
| 443 | log.debug("BGP RX UPDATE message ADDED from {}: {} nextHop {}", |
| 444 | bgpSession.getRemoteAddress(), prefix, |
| 445 | mpNlri.nextHop4); |
| 446 | } |
| 447 | // Remove from the collection of deleted routes |
| 448 | decodedBgpRoutes.deletedUnicastRoutes4.remove(prefix); |
| 449 | decodedBgpRoutes.addedUnicastRoutes4.put(prefix, |
| 450 | bgpRouteEntry); |
| 451 | } |
| 452 | |
| 453 | // The added IPv6 routes |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 454 | for (Ip6Prefix prefix : mpNlri.nlri6) { |
| 455 | bgpRouteEntry = |
| 456 | new BgpRouteEntry(bgpSession, prefix, mpNlri.nextHop6, |
| 457 | origin.byteValue(), asPath, localPref); |
| 458 | bgpRouteEntry.setMultiExitDisc(multiExitDisc); |
| 459 | if (bgpRouteEntry.hasAsPathLoop(bgpSession.getLocalAs())) { |
| 460 | log.debug("BGP RX UPDATE message IGNORED from {}: {} " + |
| 461 | "nextHop {}: contains AS Path loop", |
| 462 | bgpSession.getRemoteAddress(), prefix, |
| 463 | mpNlri.nextHop6); |
| 464 | continue; |
| 465 | } else { |
| 466 | log.debug("BGP RX UPDATE message ADDED from {}: {} nextHop {}", |
| 467 | bgpSession.getRemoteAddress(), prefix, |
| 468 | mpNlri.nextHop6); |
| 469 | } |
| 470 | // Remove from the collection of deleted routes |
| 471 | decodedBgpRoutes.deletedUnicastRoutes6.remove(prefix); |
| 472 | decodedBgpRoutes.addedUnicastRoutes6.put(prefix, |
| 473 | bgpRouteEntry); |
| 474 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 475 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 476 | } |
| 477 | |
| 478 | /** |
| 479 | * Verifies BGP UPDATE Well-known Attributes. |
| 480 | * |
| 481 | * @param bgpSession the BGP Session to use |
| 482 | * @param ctx the Channel Handler Context |
| 483 | * @param origin the ORIGIN well-known mandatory attribute |
| 484 | * @param asPath the AS_PATH well-known mandatory attribute |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 485 | * @param localPref the LOCAL_PREF required attribute |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 486 | * @param legacyNlri the legacy NLRI. Encapsulates the NEXT_HOP well-known |
| 487 | * mandatory attribute (mandatory if legacy NLRI is used). |
| 488 | * @param mpNlriReachList the Multiprotocol NLRI attributes |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 489 | * @throws BgpParseException |
| 490 | */ |
| 491 | private static void verifyBgpUpdateWellKnownAttributes( |
| 492 | BgpSession bgpSession, |
| 493 | ChannelHandlerContext ctx, |
| 494 | Short origin, |
| 495 | BgpRouteEntry.AsPath asPath, |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 496 | Long localPref, |
| 497 | MpNlri legacyNlri, |
| 498 | Collection<MpNlri> mpNlriReachList) |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 499 | throws BgpParseException { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 500 | boolean hasNlri = false; |
| 501 | boolean hasLegacyNlri = false; |
| 502 | |
| 503 | // |
| 504 | // Convenience flags that are used to check for missing attributes. |
| 505 | // |
| 506 | // NOTE: The hasLegacyNlri flag is always set to true if the |
| 507 | // Multiprotocol Extensions are not enabled, even if the UPDATE |
| 508 | // message doesn't contain the legacy NLRI (per RFC 4271). |
| 509 | // |
| 510 | if (!bgpSession.getMpExtensions()) { |
| 511 | hasNlri = true; |
| 512 | hasLegacyNlri = true; |
| 513 | } else { |
| 514 | if (!legacyNlri.nlri4.isEmpty()) { |
| 515 | hasNlri = true; |
| 516 | hasLegacyNlri = true; |
| 517 | } |
| 518 | if (!mpNlriReachList.isEmpty()) { |
| 519 | hasNlri = true; |
| 520 | } |
| 521 | } |
| 522 | |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 523 | // |
| 524 | // Check for Missing Well-known Attributes |
| 525 | // |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 526 | if (hasNlri && ((origin == null) || (origin == -1))) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 527 | // Missing Attribute Type Code ORIGIN |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 528 | int type = Update.Origin.TYPE; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 529 | actionsBgpUpdateMissingWellKnownAttribute(bgpSession, ctx, type); |
| 530 | String errorMsg = "Missing Well-known Attribute: ORIGIN"; |
| 531 | throw new BgpParseException(errorMsg); |
| 532 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 533 | if (hasNlri && (asPath == null)) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 534 | // Missing Attribute Type Code AS_PATH |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 535 | int type = Update.AsPath.TYPE; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 536 | actionsBgpUpdateMissingWellKnownAttribute(bgpSession, ctx, type); |
| 537 | String errorMsg = "Missing Well-known Attribute: AS_PATH"; |
| 538 | throw new BgpParseException(errorMsg); |
| 539 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 540 | if (hasNlri && (localPref == null)) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 541 | // Missing Attribute Type Code LOCAL_PREF |
| 542 | // NOTE: Required for iBGP |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 543 | int type = Update.LocalPref.TYPE; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 544 | actionsBgpUpdateMissingWellKnownAttribute(bgpSession, ctx, type); |
| 545 | String errorMsg = "Missing Well-known Attribute: LOCAL_PREF"; |
| 546 | throw new BgpParseException(errorMsg); |
| 547 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 548 | if (hasLegacyNlri && (legacyNlri.nextHop4 == null)) { |
| 549 | // Missing Attribute Type Code NEXT_HOP |
| 550 | int type = Update.NextHop.TYPE; |
| 551 | actionsBgpUpdateMissingWellKnownAttribute(bgpSession, ctx, type); |
| 552 | String errorMsg = "Missing Well-known Attribute: NEXT_HOP"; |
| 553 | throw new BgpParseException(errorMsg); |
| 554 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 555 | } |
| 556 | |
| 557 | /** |
| 558 | * Verifies the BGP UPDATE Attribute Flags. |
| 559 | * |
| 560 | * @param bgpSession the BGP Session to use |
| 561 | * @param ctx the Channel Handler Context |
| 562 | * @param attrTypeCode the attribute type code |
| 563 | * @param attrLen the attribute length (in octets) |
| 564 | * @param attrFlags the attribute flags |
| 565 | * @param message the message to parse |
| 566 | * @throws BgpParseException |
| 567 | */ |
| 568 | private static void verifyBgpUpdateAttributeFlags( |
| 569 | BgpSession bgpSession, |
| 570 | ChannelHandlerContext ctx, |
| 571 | int attrTypeCode, |
| 572 | int attrLen, |
| 573 | int attrFlags, |
| 574 | ChannelBuffer message) |
| 575 | throws BgpParseException { |
| 576 | |
| 577 | // |
| 578 | // Assign the Attribute Type Name and the Well-known flag |
| 579 | // |
| 580 | String typeName = "UNKNOWN"; |
| 581 | boolean isWellKnown = false; |
| 582 | switch (attrTypeCode) { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 583 | case Update.Origin.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 584 | isWellKnown = true; |
| 585 | typeName = "ORIGIN"; |
| 586 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 587 | case Update.AsPath.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 588 | isWellKnown = true; |
| 589 | typeName = "AS_PATH"; |
| 590 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 591 | case Update.NextHop.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 592 | isWellKnown = true; |
| 593 | typeName = "NEXT_HOP"; |
| 594 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 595 | case Update.MultiExitDisc.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 596 | isWellKnown = false; |
| 597 | typeName = "MULTI_EXIT_DISC"; |
| 598 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 599 | case Update.LocalPref.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 600 | isWellKnown = true; |
| 601 | typeName = "LOCAL_PREF"; |
| 602 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 603 | case Update.AtomicAggregate.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 604 | isWellKnown = true; |
| 605 | typeName = "ATOMIC_AGGREGATE"; |
| 606 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 607 | case Update.Aggregator.TYPE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 608 | isWellKnown = false; |
| 609 | typeName = "AGGREGATOR"; |
| 610 | break; |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 611 | case Update.MpReachNlri.TYPE: |
| 612 | isWellKnown = false; |
| 613 | typeName = "MP_REACH_NLRI"; |
| 614 | break; |
| 615 | case Update.MpUnreachNlri.TYPE: |
| 616 | isWellKnown = false; |
| 617 | typeName = "MP_UNREACH_NLRI"; |
| 618 | break; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 619 | default: |
| 620 | isWellKnown = false; |
| 621 | typeName = "UNKNOWN(" + attrTypeCode + ")"; |
| 622 | break; |
| 623 | } |
| 624 | |
| 625 | // |
| 626 | // Verify the Attribute Flags |
| 627 | // |
| 628 | boolean optionalBit = ((0x80 & attrFlags) != 0); |
| 629 | boolean transitiveBit = ((0x40 & attrFlags) != 0); |
| 630 | boolean partialBit = ((0x20 & attrFlags) != 0); |
| 631 | if ((isWellKnown && optionalBit) || |
| 632 | (isWellKnown && (!transitiveBit)) || |
| 633 | (isWellKnown && partialBit) || |
| 634 | (optionalBit && (!transitiveBit) && partialBit)) { |
| 635 | // |
| 636 | // ERROR: The Optional bit cannot be set for Well-known attributes |
| 637 | // ERROR: The Transtive bit MUST be 1 for well-known attributes |
| 638 | // ERROR: The Partial bit MUST be 0 for well-known attributes |
| 639 | // ERROR: The Partial bit MUST be 0 for optional non-transitive |
| 640 | // attributes |
| 641 | // |
| 642 | actionsBgpUpdateAttributeFlagsError( |
| 643 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 644 | String errorMsg = "Attribute Flags Error for " + typeName + ": " + |
| 645 | attrFlags; |
| 646 | throw new BgpParseException(errorMsg); |
| 647 | } |
| 648 | } |
| 649 | |
| 650 | /** |
| 651 | * Parses BGP UPDATE Attribute Type ORIGIN. |
| 652 | * |
| 653 | * @param bgpSession the BGP Session to use |
| 654 | * @param ctx the Channel Handler Context |
| 655 | * @param attrTypeCode the attribute type code |
| 656 | * @param attrLen the attribute length (in octets) |
| 657 | * @param attrFlags the attribute flags |
| 658 | * @param message the message to parse |
| 659 | * @return the parsed ORIGIN value |
| 660 | * @throws BgpParseException |
| 661 | */ |
| 662 | private static short parseAttributeTypeOrigin( |
| 663 | BgpSession bgpSession, |
| 664 | ChannelHandlerContext ctx, |
| 665 | int attrTypeCode, |
| 666 | int attrLen, |
| 667 | int attrFlags, |
| 668 | ChannelBuffer message) |
| 669 | throws BgpParseException { |
| 670 | |
| 671 | // Check the Attribute Length |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 672 | if (attrLen != Update.Origin.LENGTH) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 673 | // ERROR: Attribute Length Error |
| 674 | actionsBgpUpdateAttributeLengthError( |
| 675 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 676 | String errorMsg = "Attribute Length Error"; |
| 677 | throw new BgpParseException(errorMsg); |
| 678 | } |
| 679 | |
| 680 | message.markReaderIndex(); |
| 681 | short origin = message.readUnsignedByte(); |
| 682 | switch (origin) { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 683 | case Update.Origin.IGP: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 684 | // FALLTHROUGH |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 685 | case Update.Origin.EGP: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 686 | // FALLTHROUGH |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 687 | case Update.Origin.INCOMPLETE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 688 | break; |
| 689 | default: |
| 690 | // ERROR: Invalid ORIGIN Attribute |
| 691 | message.resetReaderIndex(); |
| 692 | actionsBgpUpdateInvalidOriginAttribute( |
| 693 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message, |
| 694 | origin); |
| 695 | String errorMsg = "Invalid ORIGIN Attribute: " + origin; |
| 696 | throw new BgpParseException(errorMsg); |
| 697 | } |
| 698 | |
| 699 | return origin; |
| 700 | } |
| 701 | |
| 702 | /** |
| 703 | * Parses BGP UPDATE Attribute AS Path. |
| 704 | * |
| 705 | * @param bgpSession the BGP Session to use |
| 706 | * @param ctx the Channel Handler Context |
| 707 | * @param attrTypeCode the attribute type code |
| 708 | * @param attrLen the attribute length (in octets) |
| 709 | * @param attrFlags the attribute flags |
| 710 | * @param message the message to parse |
| 711 | * @return the parsed AS Path |
| 712 | * @throws BgpParseException |
| 713 | */ |
| 714 | private static BgpRouteEntry.AsPath parseAttributeTypeAsPath( |
| 715 | BgpSession bgpSession, |
| 716 | ChannelHandlerContext ctx, |
| 717 | int attrTypeCode, |
| 718 | int attrLen, |
| 719 | int attrFlags, |
| 720 | ChannelBuffer message) |
| 721 | throws BgpParseException { |
| 722 | ArrayList<BgpRouteEntry.PathSegment> pathSegments = new ArrayList<>(); |
| 723 | |
| 724 | // |
| 725 | // Parse the message |
| 726 | // |
| 727 | while (attrLen > 0) { |
| 728 | if (attrLen < 2) { |
| 729 | // ERROR: Malformed AS_PATH |
| 730 | actionsBgpUpdateMalformedAsPath(bgpSession, ctx); |
| 731 | String errorMsg = "Malformed AS Path"; |
| 732 | throw new BgpParseException(errorMsg); |
| 733 | } |
| 734 | // Get the Path Segment Type and Length (in number of ASes) |
| 735 | short pathSegmentType = message.readUnsignedByte(); |
| 736 | short pathSegmentLength = message.readUnsignedByte(); |
| 737 | attrLen -= 2; |
| 738 | |
| 739 | // Verify the Path Segment Type |
| 740 | switch (pathSegmentType) { |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 741 | case Update.AsPath.AS_SET: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 742 | // FALLTHROUGH |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 743 | case Update.AsPath.AS_SEQUENCE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 744 | // FALLTHROUGH |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 745 | case Update.AsPath.AS_CONFED_SEQUENCE: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 746 | // FALLTHROUGH |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 747 | case Update.AsPath.AS_CONFED_SET: |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 748 | break; |
| 749 | default: |
| 750 | // ERROR: Invalid Path Segment Type |
| 751 | // |
| 752 | // NOTE: The BGP Spec (RFC 4271) doesn't contain Error Subcode |
| 753 | // for "Invalid Path Segment Type", hence we return |
| 754 | // the error as "Malformed AS_PATH". |
| 755 | // |
| 756 | actionsBgpUpdateMalformedAsPath(bgpSession, ctx); |
| 757 | String errorMsg = |
| 758 | "Invalid AS Path Segment Type: " + pathSegmentType; |
| 759 | throw new BgpParseException(errorMsg); |
| 760 | } |
| 761 | |
Kunihiro Ishiguro | 923d9d8 | 2014-12-21 15:47:28 +0900 | [diff] [blame] | 762 | // 4-octet AS number handling. |
| 763 | int asPathLen; |
| 764 | if (bgpSession.isAs4OctetCapable()) { |
| 765 | asPathLen = AsPath.AS_4OCTET_LENGTH; |
| 766 | } else { |
| 767 | asPathLen = AsPath.AS_LENGTH; |
| 768 | } |
| 769 | |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 770 | // Parse the AS numbers |
Kunihiro Ishiguro | 923d9d8 | 2014-12-21 15:47:28 +0900 | [diff] [blame] | 771 | if (asPathLen * pathSegmentLength > attrLen) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 772 | // ERROR: Malformed AS_PATH |
| 773 | actionsBgpUpdateMalformedAsPath(bgpSession, ctx); |
| 774 | String errorMsg = "Malformed AS Path"; |
| 775 | throw new BgpParseException(errorMsg); |
| 776 | } |
Kunihiro Ishiguro | 923d9d8 | 2014-12-21 15:47:28 +0900 | [diff] [blame] | 777 | attrLen -= (asPathLen * pathSegmentLength); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 778 | ArrayList<Long> segmentAsNumbers = new ArrayList<>(); |
| 779 | while (pathSegmentLength-- > 0) { |
Kunihiro Ishiguro | 923d9d8 | 2014-12-21 15:47:28 +0900 | [diff] [blame] | 780 | long asNumber; |
| 781 | if (asPathLen == AsPath.AS_4OCTET_LENGTH) { |
| 782 | asNumber = message.readUnsignedInt(); |
| 783 | } else { |
| 784 | asNumber = message.readUnsignedShort(); |
| 785 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 786 | segmentAsNumbers.add(asNumber); |
| 787 | } |
| 788 | |
| 789 | BgpRouteEntry.PathSegment pathSegment = |
| 790 | new BgpRouteEntry.PathSegment((byte) pathSegmentType, |
| 791 | segmentAsNumbers); |
| 792 | pathSegments.add(pathSegment); |
| 793 | } |
| 794 | |
| 795 | return new BgpRouteEntry.AsPath(pathSegments); |
| 796 | } |
| 797 | |
| 798 | /** |
| 799 | * Parses BGP UPDATE Attribute Type NEXT_HOP. |
| 800 | * |
| 801 | * @param bgpSession the BGP Session to use |
| 802 | * @param ctx the Channel Handler Context |
| 803 | * @param attrTypeCode the attribute type code |
| 804 | * @param attrLen the attribute length (in octets) |
| 805 | * @param attrFlags the attribute flags |
| 806 | * @param message the message to parse |
| 807 | * @return the parsed NEXT_HOP value |
| 808 | * @throws BgpParseException |
| 809 | */ |
| 810 | private static Ip4Address parseAttributeTypeNextHop( |
| 811 | BgpSession bgpSession, |
| 812 | ChannelHandlerContext ctx, |
| 813 | int attrTypeCode, |
| 814 | int attrLen, |
| 815 | int attrFlags, |
| 816 | ChannelBuffer message) |
| 817 | throws BgpParseException { |
| 818 | |
| 819 | // Check the Attribute Length |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 820 | if (attrLen != Update.NextHop.LENGTH) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 821 | // ERROR: Attribute Length Error |
| 822 | actionsBgpUpdateAttributeLengthError( |
| 823 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 824 | String errorMsg = "Attribute Length Error"; |
| 825 | throw new BgpParseException(errorMsg); |
| 826 | } |
| 827 | |
| 828 | message.markReaderIndex(); |
| 829 | Ip4Address nextHopAddress = |
| 830 | Ip4Address.valueOf((int) message.readUnsignedInt()); |
| 831 | // |
| 832 | // Check whether the NEXT_HOP IP address is semantically correct. |
| 833 | // As per RFC 4271, Section 6.3: |
| 834 | // |
| 835 | // a) It MUST NOT be the IP address of the receiving speaker |
| 836 | // b) In the case of an EBGP .... |
| 837 | // |
| 838 | // Here we check only (a), because (b) doesn't apply for us: all our |
| 839 | // peers are iBGP. |
| 840 | // |
| 841 | if (nextHopAddress.equals(bgpSession.getLocalIp4Address())) { |
| 842 | // ERROR: Invalid NEXT_HOP Attribute |
| 843 | message.resetReaderIndex(); |
| 844 | actionsBgpUpdateInvalidNextHopAttribute( |
| 845 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message, |
| 846 | nextHopAddress); |
| 847 | String errorMsg = "Invalid NEXT_HOP Attribute: " + nextHopAddress; |
| 848 | throw new BgpParseException(errorMsg); |
| 849 | } |
| 850 | |
| 851 | return nextHopAddress; |
| 852 | } |
| 853 | |
| 854 | /** |
| 855 | * Parses BGP UPDATE Attribute Type MULTI_EXIT_DISC. |
| 856 | * |
| 857 | * @param bgpSession the BGP Session to use |
| 858 | * @param ctx the Channel Handler Context |
| 859 | * @param attrTypeCode the attribute type code |
| 860 | * @param attrLen the attribute length (in octets) |
| 861 | * @param attrFlags the attribute flags |
| 862 | * @param message the message to parse |
| 863 | * @return the parsed MULTI_EXIT_DISC value |
| 864 | * @throws BgpParseException |
| 865 | */ |
| 866 | private static long parseAttributeTypeMultiExitDisc( |
| 867 | BgpSession bgpSession, |
| 868 | ChannelHandlerContext ctx, |
| 869 | int attrTypeCode, |
| 870 | int attrLen, |
| 871 | int attrFlags, |
| 872 | ChannelBuffer message) |
| 873 | throws BgpParseException { |
| 874 | |
| 875 | // Check the Attribute Length |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 876 | if (attrLen != Update.MultiExitDisc.LENGTH) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 877 | // ERROR: Attribute Length Error |
| 878 | actionsBgpUpdateAttributeLengthError( |
| 879 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 880 | String errorMsg = "Attribute Length Error"; |
| 881 | throw new BgpParseException(errorMsg); |
| 882 | } |
| 883 | |
| 884 | long multiExitDisc = message.readUnsignedInt(); |
| 885 | return multiExitDisc; |
| 886 | } |
| 887 | |
| 888 | /** |
| 889 | * Parses BGP UPDATE Attribute Type LOCAL_PREF. |
| 890 | * |
| 891 | * @param bgpSession the BGP Session to use |
| 892 | * @param ctx the Channel Handler Context |
| 893 | * @param attrTypeCode the attribute type code |
| 894 | * @param attrLen the attribute length (in octets) |
| 895 | * @param attrFlags the attribute flags |
| 896 | * @param message the message to parse |
| 897 | * @return the parsed LOCAL_PREF value |
| 898 | * @throws BgpParseException |
| 899 | */ |
| 900 | private static long parseAttributeTypeLocalPref( |
| 901 | BgpSession bgpSession, |
| 902 | ChannelHandlerContext ctx, |
| 903 | int attrTypeCode, |
| 904 | int attrLen, |
| 905 | int attrFlags, |
| 906 | ChannelBuffer message) |
| 907 | throws BgpParseException { |
| 908 | |
| 909 | // Check the Attribute Length |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 910 | if (attrLen != Update.LocalPref.LENGTH) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 911 | // ERROR: Attribute Length Error |
| 912 | actionsBgpUpdateAttributeLengthError( |
| 913 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 914 | String errorMsg = "Attribute Length Error"; |
| 915 | throw new BgpParseException(errorMsg); |
| 916 | } |
| 917 | |
| 918 | long localPref = message.readUnsignedInt(); |
| 919 | return localPref; |
| 920 | } |
| 921 | |
| 922 | /** |
| 923 | * Parses BGP UPDATE Attribute Type ATOMIC_AGGREGATE. |
| 924 | * |
| 925 | * @param bgpSession the BGP Session to use |
| 926 | * @param ctx the Channel Handler Context |
| 927 | * @param attrTypeCode the attribute type code |
| 928 | * @param attrLen the attribute length (in octets) |
| 929 | * @param attrFlags the attribute flags |
| 930 | * @param message the message to parse |
| 931 | * @throws BgpParseException |
| 932 | */ |
| 933 | private static void parseAttributeTypeAtomicAggregate( |
| 934 | BgpSession bgpSession, |
| 935 | ChannelHandlerContext ctx, |
| 936 | int attrTypeCode, |
| 937 | int attrLen, |
| 938 | int attrFlags, |
| 939 | ChannelBuffer message) |
| 940 | throws BgpParseException { |
| 941 | |
| 942 | // Check the Attribute Length |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 943 | if (attrLen != Update.AtomicAggregate.LENGTH) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 944 | // ERROR: Attribute Length Error |
| 945 | actionsBgpUpdateAttributeLengthError( |
| 946 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 947 | String errorMsg = "Attribute Length Error"; |
| 948 | throw new BgpParseException(errorMsg); |
| 949 | } |
| 950 | |
| 951 | // Nothing to do: this attribute is primarily informational |
| 952 | } |
| 953 | |
| 954 | /** |
| 955 | * Parses BGP UPDATE Attribute Type AGGREGATOR. |
| 956 | * |
| 957 | * @param bgpSession the BGP Session to use |
| 958 | * @param ctx the Channel Handler Context |
| 959 | * @param attrTypeCode the attribute type code |
| 960 | * @param attrLen the attribute length (in octets) |
| 961 | * @param attrFlags the attribute flags |
| 962 | * @param message the message to parse |
| 963 | * @return the parsed AGGREGATOR value: a tuple of <AS-Number, IP-Address> |
| 964 | * @throws BgpParseException |
| 965 | */ |
| 966 | private static Pair<Long, Ip4Address> parseAttributeTypeAggregator( |
| 967 | BgpSession bgpSession, |
| 968 | ChannelHandlerContext ctx, |
| 969 | int attrTypeCode, |
| 970 | int attrLen, |
| 971 | int attrFlags, |
| 972 | ChannelBuffer message) |
| 973 | throws BgpParseException { |
| 974 | |
| 975 | // Check the Attribute Length |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 976 | if (attrLen != Update.Aggregator.LENGTH) { |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 977 | // ERROR: Attribute Length Error |
| 978 | actionsBgpUpdateAttributeLengthError( |
| 979 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 980 | String errorMsg = "Attribute Length Error"; |
| 981 | throw new BgpParseException(errorMsg); |
| 982 | } |
| 983 | |
| 984 | // The AGGREGATOR AS number |
| 985 | long aggregatorAsNumber = message.readUnsignedShort(); |
| 986 | // The AGGREGATOR IP address |
| 987 | Ip4Address aggregatorIpAddress = |
| 988 | Ip4Address.valueOf((int) message.readUnsignedInt()); |
| 989 | |
| 990 | Pair<Long, Ip4Address> aggregator = Pair.of(aggregatorAsNumber, |
| 991 | aggregatorIpAddress); |
| 992 | return aggregator; |
| 993 | } |
| 994 | |
| 995 | /** |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 996 | * Parses BGP UPDATE Attribute Type MP_REACH_NLRI. |
| 997 | * |
| 998 | * @param bgpSession the BGP Session to use |
| 999 | * @param ctx the Channel Handler Context |
| 1000 | * @param attrTypeCode the attribute type code |
| 1001 | * @param attrLen the attribute length (in octets) |
| 1002 | * @param attrFlags the attribute flags |
| 1003 | * @param message the message to parse |
| 1004 | * @return the parsed MP_REACH_NLRI information if recognized, otherwise |
| 1005 | * null |
| 1006 | * @throws BgpParseException |
| 1007 | */ |
| 1008 | private static MpNlri parseAttributeTypeMpReachNlri( |
| 1009 | BgpSession bgpSession, |
| 1010 | ChannelHandlerContext ctx, |
| 1011 | int attrTypeCode, |
| 1012 | int attrLen, |
| 1013 | int attrFlags, |
| 1014 | ChannelBuffer message) |
| 1015 | throws BgpParseException { |
| 1016 | int attributeEnd = message.readerIndex() + attrLen; |
| 1017 | |
| 1018 | // Check the Attribute Length |
| 1019 | if (attrLen < Update.MpReachNlri.MIN_LENGTH) { |
| 1020 | // ERROR: Attribute Length Error |
| 1021 | actionsBgpUpdateAttributeLengthError( |
| 1022 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 1023 | String errorMsg = "Attribute Length Error"; |
| 1024 | throw new BgpParseException(errorMsg); |
| 1025 | } |
| 1026 | |
| 1027 | message.markReaderIndex(); |
| 1028 | int afi = message.readUnsignedShort(); |
| 1029 | int safi = message.readUnsignedByte(); |
| 1030 | int nextHopLen = message.readUnsignedByte(); |
| 1031 | |
| 1032 | // |
| 1033 | // Verify the AFI/SAFI, and skip the attribute if not recognized. |
| 1034 | // NOTE: Currently, we support only IPv4/IPv6 UNICAST |
| 1035 | // |
| 1036 | if (((afi != MultiprotocolExtensions.AFI_IPV4) && |
| 1037 | (afi != MultiprotocolExtensions.AFI_IPV6)) || |
| 1038 | (safi != MultiprotocolExtensions.SAFI_UNICAST)) { |
| 1039 | // Skip the attribute |
| 1040 | message.resetReaderIndex(); |
| 1041 | message.skipBytes(attrLen); |
| 1042 | return null; |
| 1043 | } |
| 1044 | |
| 1045 | // |
| 1046 | // Verify the next-hop length |
| 1047 | // |
| 1048 | int expectedNextHopLen = 0; |
| 1049 | switch (afi) { |
| 1050 | case MultiprotocolExtensions.AFI_IPV4: |
| 1051 | expectedNextHopLen = Ip4Address.BYTE_LENGTH; |
| 1052 | break; |
| 1053 | case MultiprotocolExtensions.AFI_IPV6: |
| 1054 | expectedNextHopLen = Ip6Address.BYTE_LENGTH; |
| 1055 | break; |
| 1056 | default: |
| 1057 | // UNREACHABLE |
| 1058 | break; |
| 1059 | } |
| 1060 | if (nextHopLen != expectedNextHopLen) { |
| 1061 | // ERROR: Optional Attribute Error |
| 1062 | message.resetReaderIndex(); |
| 1063 | actionsBgpUpdateOptionalAttributeError( |
| 1064 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 1065 | String errorMsg = "Invalid next-hop network address length. " + |
| 1066 | "Received " + nextHopLen + " expected " + expectedNextHopLen; |
| 1067 | throw new BgpParseException(errorMsg); |
| 1068 | } |
| 1069 | // NOTE: We use "+ 1" to take into account the Reserved field (1 octet) |
| 1070 | if (message.readerIndex() + nextHopLen + 1 >= attributeEnd) { |
| 1071 | // ERROR: Optional Attribute Error |
| 1072 | message.resetReaderIndex(); |
| 1073 | actionsBgpUpdateOptionalAttributeError( |
| 1074 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 1075 | String errorMsg = "Malformed next-hop network address"; |
| 1076 | throw new BgpParseException(errorMsg); |
| 1077 | } |
| 1078 | |
| 1079 | // |
| 1080 | // Get the Next-hop address, skip the Reserved field, and get the NLRI |
| 1081 | // |
| 1082 | byte[] nextHopBuffer = new byte[nextHopLen]; |
| 1083 | message.readBytes(nextHopBuffer, 0, nextHopLen); |
| 1084 | int reserved = message.readUnsignedByte(); |
| 1085 | MpNlri mpNlri = new MpNlri(afi, safi); |
| 1086 | try { |
| 1087 | switch (afi) { |
| 1088 | case MultiprotocolExtensions.AFI_IPV4: |
| 1089 | // The next-hop address |
| 1090 | mpNlri.nextHop4 = Ip4Address.valueOf(nextHopBuffer); |
| 1091 | // The NLRI |
| 1092 | mpNlri.nlri4 = parsePackedIp4Prefixes( |
| 1093 | attributeEnd - message.readerIndex(), |
| 1094 | message); |
| 1095 | break; |
| 1096 | case MultiprotocolExtensions.AFI_IPV6: |
| 1097 | // The next-hop address |
| 1098 | mpNlri.nextHop6 = Ip6Address.valueOf(nextHopBuffer); |
| 1099 | // The NLRI |
| 1100 | mpNlri.nlri6 = parsePackedIp6Prefixes( |
| 1101 | attributeEnd - message.readerIndex(), |
| 1102 | message); |
| 1103 | break; |
| 1104 | default: |
| 1105 | // UNREACHABLE |
| 1106 | break; |
| 1107 | } |
| 1108 | } catch (BgpParseException e) { |
| 1109 | // ERROR: Optional Attribute Error |
| 1110 | message.resetReaderIndex(); |
| 1111 | actionsBgpUpdateOptionalAttributeError( |
| 1112 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 1113 | String errorMsg = "Malformed network layer reachability information"; |
| 1114 | throw new BgpParseException(errorMsg); |
| 1115 | } |
| 1116 | |
| 1117 | return mpNlri; |
| 1118 | } |
| 1119 | |
| 1120 | /** |
| 1121 | * Parses BGP UPDATE Attribute Type MP_UNREACH_NLRI. |
| 1122 | * |
| 1123 | * @param bgpSession the BGP Session to use |
| 1124 | * @param ctx the Channel Handler Context |
| 1125 | * @param attrTypeCode the attribute type code |
| 1126 | * @param attrLen the attribute length (in octets) |
| 1127 | * @param attrFlags the attribute flags |
| 1128 | * @param message the message to parse |
| 1129 | * @return the parsed MP_UNREACH_NLRI information if recognized, otherwise |
| 1130 | * null |
| 1131 | * @throws BgpParseException |
| 1132 | */ |
| 1133 | private static MpNlri parseAttributeTypeMpUnreachNlri( |
| 1134 | BgpSession bgpSession, |
| 1135 | ChannelHandlerContext ctx, |
| 1136 | int attrTypeCode, |
| 1137 | int attrLen, |
| 1138 | int attrFlags, |
| 1139 | ChannelBuffer message) |
| 1140 | throws BgpParseException { |
| 1141 | int attributeEnd = message.readerIndex() + attrLen; |
| 1142 | |
| 1143 | // Check the Attribute Length |
| 1144 | if (attrLen < Update.MpUnreachNlri.MIN_LENGTH) { |
| 1145 | // ERROR: Attribute Length Error |
| 1146 | actionsBgpUpdateAttributeLengthError( |
| 1147 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 1148 | String errorMsg = "Attribute Length Error"; |
| 1149 | throw new BgpParseException(errorMsg); |
| 1150 | } |
| 1151 | |
| 1152 | message.markReaderIndex(); |
| 1153 | int afi = message.readUnsignedShort(); |
| 1154 | int safi = message.readUnsignedByte(); |
| 1155 | |
| 1156 | // |
| 1157 | // Verify the AFI/SAFI, and skip the attribute if not recognized. |
| 1158 | // NOTE: Currently, we support only IPv4/IPv6 UNICAST |
| 1159 | // |
| 1160 | if (((afi != MultiprotocolExtensions.AFI_IPV4) && |
| 1161 | (afi != MultiprotocolExtensions.AFI_IPV6)) || |
| 1162 | (safi != MultiprotocolExtensions.SAFI_UNICAST)) { |
| 1163 | // Skip the attribute |
| 1164 | message.resetReaderIndex(); |
| 1165 | message.skipBytes(attrLen); |
| 1166 | return null; |
| 1167 | } |
| 1168 | |
| 1169 | // |
| 1170 | // Get the Withdrawn Routes |
| 1171 | // |
| 1172 | MpNlri mpNlri = new MpNlri(afi, safi); |
| 1173 | try { |
| 1174 | switch (afi) { |
| 1175 | case MultiprotocolExtensions.AFI_IPV4: |
| 1176 | // The Withdrawn Routes |
| 1177 | mpNlri.nlri4 = parsePackedIp4Prefixes( |
| 1178 | attributeEnd - message.readerIndex(), |
| 1179 | message); |
| 1180 | break; |
| 1181 | case MultiprotocolExtensions.AFI_IPV6: |
| 1182 | // The Withdrawn Routes |
| 1183 | mpNlri.nlri6 = parsePackedIp6Prefixes( |
| 1184 | attributeEnd - message.readerIndex(), |
| 1185 | message); |
| 1186 | break; |
| 1187 | default: |
| 1188 | // UNREACHABLE |
| 1189 | break; |
| 1190 | } |
| 1191 | } catch (BgpParseException e) { |
| 1192 | // ERROR: Optional Attribute Error |
| 1193 | message.resetReaderIndex(); |
| 1194 | actionsBgpUpdateOptionalAttributeError( |
| 1195 | bgpSession, ctx, attrTypeCode, attrLen, attrFlags, message); |
| 1196 | String errorMsg = "Malformed withdrawn routes"; |
| 1197 | throw new BgpParseException(errorMsg); |
| 1198 | } |
| 1199 | |
| 1200 | return mpNlri; |
| 1201 | } |
| 1202 | |
| 1203 | /** |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1204 | * Parses a message that contains encoded IPv4 network prefixes. |
| 1205 | * <p> |
| 1206 | * The IPv4 prefixes are encoded in the form: |
| 1207 | * <Length, Prefix> where Length is the length in bits of the IPv4 prefix, |
| 1208 | * and Prefix is the IPv4 prefix (padded with trailing bits to the end |
| 1209 | * of an octet). |
| 1210 | * |
| 1211 | * @param totalLength the total length of the data to parse |
| 1212 | * @param message the message with data to parse |
| 1213 | * @return a collection of parsed IPv4 network prefixes |
| 1214 | * @throws BgpParseException |
| 1215 | */ |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1216 | private static Collection<Ip4Prefix> parsePackedIp4Prefixes( |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1217 | int totalLength, |
| 1218 | ChannelBuffer message) |
| 1219 | throws BgpParseException { |
| 1220 | Collection<Ip4Prefix> result = new ArrayList<>(); |
| 1221 | |
| 1222 | if (totalLength == 0) { |
| 1223 | return result; |
| 1224 | } |
| 1225 | |
| 1226 | // Parse the data |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1227 | byte[] buffer = new byte[Ip4Address.BYTE_LENGTH]; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1228 | int dataEnd = message.readerIndex() + totalLength; |
| 1229 | while (message.readerIndex() < dataEnd) { |
| 1230 | int prefixBitlen = message.readUnsignedByte(); |
| 1231 | int prefixBytelen = (prefixBitlen + 7) / 8; // Round-up |
| 1232 | if (message.readerIndex() + prefixBytelen > dataEnd) { |
| 1233 | String errorMsg = "Malformed Network Prefixes"; |
| 1234 | throw new BgpParseException(errorMsg); |
| 1235 | } |
| 1236 | |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1237 | message.readBytes(buffer, 0, prefixBytelen); |
| 1238 | Ip4Prefix prefix = Ip4Prefix.valueOf(Ip4Address.valueOf(buffer), |
| 1239 | prefixBitlen); |
| 1240 | result.add(prefix); |
| 1241 | } |
| 1242 | |
| 1243 | return result; |
| 1244 | } |
| 1245 | |
| 1246 | /** |
| 1247 | * Parses a message that contains encoded IPv6 network prefixes. |
| 1248 | * <p> |
| 1249 | * The IPv6 prefixes are encoded in the form: |
| 1250 | * <Length, Prefix> where Length is the length in bits of the IPv6 prefix, |
| 1251 | * and Prefix is the IPv6 prefix (padded with trailing bits to the end |
| 1252 | * of an octet). |
| 1253 | * |
| 1254 | * @param totalLength the total length of the data to parse |
| 1255 | * @param message the message with data to parse |
| 1256 | * @return a collection of parsed IPv6 network prefixes |
| 1257 | * @throws BgpParseException |
| 1258 | */ |
| 1259 | private static Collection<Ip6Prefix> parsePackedIp6Prefixes( |
| 1260 | int totalLength, |
| 1261 | ChannelBuffer message) |
| 1262 | throws BgpParseException { |
| 1263 | Collection<Ip6Prefix> result = new ArrayList<>(); |
| 1264 | |
| 1265 | if (totalLength == 0) { |
| 1266 | return result; |
| 1267 | } |
| 1268 | |
| 1269 | // Parse the data |
| 1270 | byte[] buffer = new byte[Ip6Address.BYTE_LENGTH]; |
| 1271 | int dataEnd = message.readerIndex() + totalLength; |
| 1272 | while (message.readerIndex() < dataEnd) { |
| 1273 | int prefixBitlen = message.readUnsignedByte(); |
| 1274 | int prefixBytelen = (prefixBitlen + 7) / 8; // Round-up |
| 1275 | if (message.readerIndex() + prefixBytelen > dataEnd) { |
| 1276 | String errorMsg = "Malformed Network Prefixes"; |
| 1277 | throw new BgpParseException(errorMsg); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1278 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1279 | |
| 1280 | message.readBytes(buffer, 0, prefixBytelen); |
| 1281 | Ip6Prefix prefix = Ip6Prefix.valueOf(Ip6Address.valueOf(buffer), |
| 1282 | prefixBitlen); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1283 | result.add(prefix); |
| 1284 | } |
| 1285 | |
| 1286 | return result; |
| 1287 | } |
| 1288 | |
| 1289 | /** |
| 1290 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1291 | * Invalid Network Field Error: send NOTIFICATION and close the channel. |
| 1292 | * |
| 1293 | * @param bgpSession the BGP Session to use |
| 1294 | * @param ctx the Channel Handler Context |
| 1295 | */ |
| 1296 | private static void actionsBgpUpdateInvalidNetworkField( |
| 1297 | BgpSession bgpSession, |
| 1298 | ChannelHandlerContext ctx) { |
| 1299 | log.debug("BGP RX UPDATE Error from {}: Invalid Network Field", |
| 1300 | bgpSession.getRemoteAddress()); |
| 1301 | |
| 1302 | // |
| 1303 | // ERROR: Invalid Network Field |
| 1304 | // |
| 1305 | // Send NOTIFICATION and close the connection |
| 1306 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1307 | int errorSubcode = UpdateMessageError.INVALID_NETWORK_FIELD; |
| 1308 | ChannelBuffer txMessage = |
| 1309 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1310 | null); |
| 1311 | ctx.getChannel().write(txMessage); |
| 1312 | bgpSession.closeSession(ctx); |
| 1313 | } |
| 1314 | |
| 1315 | /** |
| 1316 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1317 | * Malformed Attribute List Error: send NOTIFICATION and close the channel. |
| 1318 | * |
| 1319 | * @param bgpSession the BGP Session to use |
| 1320 | * @param ctx the Channel Handler Context |
| 1321 | */ |
| 1322 | private static void actionsBgpUpdateMalformedAttributeList( |
| 1323 | BgpSession bgpSession, |
| 1324 | ChannelHandlerContext ctx) { |
| 1325 | log.debug("BGP RX UPDATE Error from {}: Malformed Attribute List", |
| 1326 | bgpSession.getRemoteAddress()); |
| 1327 | |
| 1328 | // |
| 1329 | // ERROR: Malformed Attribute List |
| 1330 | // |
| 1331 | // Send NOTIFICATION and close the connection |
| 1332 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1333 | int errorSubcode = UpdateMessageError.MALFORMED_ATTRIBUTE_LIST; |
| 1334 | ChannelBuffer txMessage = |
| 1335 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1336 | null); |
| 1337 | ctx.getChannel().write(txMessage); |
| 1338 | bgpSession.closeSession(ctx); |
| 1339 | } |
| 1340 | |
| 1341 | /** |
| 1342 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1343 | * Missing Well-known Attribute Error: send NOTIFICATION and close the |
| 1344 | * channel. |
| 1345 | * |
| 1346 | * @param bgpSession the BGP Session to use |
| 1347 | * @param ctx the Channel Handler Context |
| 1348 | * @param missingAttrTypeCode the missing attribute type code |
| 1349 | */ |
| 1350 | private static void actionsBgpUpdateMissingWellKnownAttribute( |
| 1351 | BgpSession bgpSession, |
| 1352 | ChannelHandlerContext ctx, |
| 1353 | int missingAttrTypeCode) { |
| 1354 | log.debug("BGP RX UPDATE Error from {}: Missing Well-known Attribute: {}", |
| 1355 | bgpSession.getRemoteAddress(), missingAttrTypeCode); |
| 1356 | |
| 1357 | // |
| 1358 | // ERROR: Missing Well-known Attribute |
| 1359 | // |
| 1360 | // Send NOTIFICATION and close the connection |
| 1361 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1362 | int errorSubcode = UpdateMessageError.MISSING_WELL_KNOWN_ATTRIBUTE; |
| 1363 | ChannelBuffer data = ChannelBuffers.buffer(1); |
| 1364 | data.writeByte(missingAttrTypeCode); |
| 1365 | ChannelBuffer txMessage = |
| 1366 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1367 | data); |
| 1368 | ctx.getChannel().write(txMessage); |
| 1369 | bgpSession.closeSession(ctx); |
| 1370 | } |
| 1371 | |
| 1372 | /** |
| 1373 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1374 | * Invalid ORIGIN Attribute Error: send NOTIFICATION and close the channel. |
| 1375 | * |
| 1376 | * @param bgpSession the BGP Session to use |
| 1377 | * @param ctx the Channel Handler Context |
| 1378 | * @param attrTypeCode the attribute type code |
| 1379 | * @param attrLen the attribute length (in octets) |
| 1380 | * @param attrFlags the attribute flags |
| 1381 | * @param message the message with the data |
| 1382 | * @param origin the ORIGIN attribute value |
| 1383 | */ |
| 1384 | private static void actionsBgpUpdateInvalidOriginAttribute( |
| 1385 | BgpSession bgpSession, |
| 1386 | ChannelHandlerContext ctx, |
| 1387 | int attrTypeCode, |
| 1388 | int attrLen, |
| 1389 | int attrFlags, |
| 1390 | ChannelBuffer message, |
| 1391 | short origin) { |
| 1392 | log.debug("BGP RX UPDATE Error from {}: Invalid ORIGIN Attribute", |
| 1393 | bgpSession.getRemoteAddress()); |
| 1394 | |
| 1395 | // |
| 1396 | // ERROR: Invalid ORIGIN Attribute |
| 1397 | // |
| 1398 | // Send NOTIFICATION and close the connection |
| 1399 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1400 | int errorSubcode = UpdateMessageError.INVALID_ORIGIN_ATTRIBUTE; |
| 1401 | ChannelBuffer data = |
| 1402 | prepareBgpUpdateNotificationDataPayload(attrTypeCode, attrLen, |
| 1403 | attrFlags, message); |
| 1404 | ChannelBuffer txMessage = |
| 1405 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1406 | data); |
| 1407 | ctx.getChannel().write(txMessage); |
| 1408 | bgpSession.closeSession(ctx); |
| 1409 | } |
| 1410 | |
| 1411 | /** |
| 1412 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1413 | * Attribute Flags Error: send NOTIFICATION and close the channel. |
| 1414 | * |
| 1415 | * @param bgpSession the BGP Session to use |
| 1416 | * @param ctx the Channel Handler Context |
| 1417 | * @param attrTypeCode the attribute type code |
| 1418 | * @param attrLen the attribute length (in octets) |
| 1419 | * @param attrFlags the attribute flags |
| 1420 | * @param message the message with the data |
| 1421 | */ |
| 1422 | private static void actionsBgpUpdateAttributeFlagsError( |
| 1423 | BgpSession bgpSession, |
| 1424 | ChannelHandlerContext ctx, |
| 1425 | int attrTypeCode, |
| 1426 | int attrLen, |
| 1427 | int attrFlags, |
| 1428 | ChannelBuffer message) { |
| 1429 | log.debug("BGP RX UPDATE Error from {}: Attribute Flags Error", |
| 1430 | bgpSession.getRemoteAddress()); |
| 1431 | |
| 1432 | // |
| 1433 | // ERROR: Attribute Flags Error |
| 1434 | // |
| 1435 | // Send NOTIFICATION and close the connection |
| 1436 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1437 | int errorSubcode = UpdateMessageError.ATTRIBUTE_FLAGS_ERROR; |
| 1438 | ChannelBuffer data = |
| 1439 | prepareBgpUpdateNotificationDataPayload(attrTypeCode, attrLen, |
| 1440 | attrFlags, message); |
| 1441 | ChannelBuffer txMessage = |
| 1442 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1443 | data); |
| 1444 | ctx.getChannel().write(txMessage); |
| 1445 | bgpSession.closeSession(ctx); |
| 1446 | } |
| 1447 | |
| 1448 | /** |
| 1449 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1450 | * Invalid NEXT_HOP Attribute Error: send NOTIFICATION and close the |
| 1451 | * channel. |
| 1452 | * |
| 1453 | * @param bgpSession the BGP Session to use |
| 1454 | * @param ctx the Channel Handler Context |
| 1455 | * @param attrTypeCode the attribute type code |
| 1456 | * @param attrLen the attribute length (in octets) |
| 1457 | * @param attrFlags the attribute flags |
| 1458 | * @param message the message with the data |
| 1459 | * @param nextHop the NEXT_HOP attribute value |
| 1460 | */ |
| 1461 | private static void actionsBgpUpdateInvalidNextHopAttribute( |
| 1462 | BgpSession bgpSession, |
| 1463 | ChannelHandlerContext ctx, |
| 1464 | int attrTypeCode, |
| 1465 | int attrLen, |
| 1466 | int attrFlags, |
| 1467 | ChannelBuffer message, |
| 1468 | Ip4Address nextHop) { |
| 1469 | log.debug("BGP RX UPDATE Error from {}: Invalid NEXT_HOP Attribute {}", |
| 1470 | bgpSession.getRemoteAddress(), nextHop); |
| 1471 | |
| 1472 | // |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1473 | // ERROR: Invalid NEXT_HOP Attribute |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1474 | // |
| 1475 | // Send NOTIFICATION and close the connection |
| 1476 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1477 | int errorSubcode = UpdateMessageError.INVALID_NEXT_HOP_ATTRIBUTE; |
| 1478 | ChannelBuffer data = |
| 1479 | prepareBgpUpdateNotificationDataPayload(attrTypeCode, attrLen, |
| 1480 | attrFlags, message); |
| 1481 | ChannelBuffer txMessage = |
| 1482 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1483 | data); |
| 1484 | ctx.getChannel().write(txMessage); |
| 1485 | bgpSession.closeSession(ctx); |
| 1486 | } |
| 1487 | |
| 1488 | /** |
| 1489 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1490 | * Unrecognized Well-known Attribute Error: send NOTIFICATION and close |
| 1491 | * the channel. |
| 1492 | * |
| 1493 | * @param bgpSession the BGP Session to use |
| 1494 | * @param ctx the Channel Handler Context |
| 1495 | * @param attrTypeCode the attribute type code |
| 1496 | * @param attrLen the attribute length (in octets) |
| 1497 | * @param attrFlags the attribute flags |
| 1498 | * @param message the message with the data |
| 1499 | */ |
| 1500 | private static void actionsBgpUpdateUnrecognizedWellKnownAttribute( |
| 1501 | BgpSession bgpSession, |
| 1502 | ChannelHandlerContext ctx, |
| 1503 | int attrTypeCode, |
| 1504 | int attrLen, |
| 1505 | int attrFlags, |
| 1506 | ChannelBuffer message) { |
| 1507 | log.debug("BGP RX UPDATE Error from {}: " + |
| 1508 | "Unrecognized Well-known Attribute Error: {}", |
| 1509 | bgpSession.getRemoteAddress(), attrTypeCode); |
| 1510 | |
| 1511 | // |
| 1512 | // ERROR: Unrecognized Well-known Attribute |
| 1513 | // |
| 1514 | // Send NOTIFICATION and close the connection |
| 1515 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1516 | int errorSubcode = |
| 1517 | UpdateMessageError.UNRECOGNIZED_WELL_KNOWN_ATTRIBUTE; |
| 1518 | ChannelBuffer data = |
| 1519 | prepareBgpUpdateNotificationDataPayload(attrTypeCode, attrLen, |
| 1520 | attrFlags, message); |
| 1521 | ChannelBuffer txMessage = |
| 1522 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1523 | data); |
| 1524 | ctx.getChannel().write(txMessage); |
| 1525 | bgpSession.closeSession(ctx); |
| 1526 | } |
| 1527 | |
| 1528 | /** |
| 1529 | * Applies the appropriate actions after detecting BGP UPDATE |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1530 | * Optional Attribute Error: send NOTIFICATION and close |
| 1531 | * the channel. |
| 1532 | * |
| 1533 | * @param bgpSession the BGP Session to use |
| 1534 | * @param ctx the Channel Handler Context |
| 1535 | * @param attrTypeCode the attribute type code |
| 1536 | * @param attrLen the attribute length (in octets) |
| 1537 | * @param attrFlags the attribute flags |
| 1538 | * @param message the message with the data |
| 1539 | */ |
| 1540 | private static void actionsBgpUpdateOptionalAttributeError( |
| 1541 | BgpSession bgpSession, |
| 1542 | ChannelHandlerContext ctx, |
| 1543 | int attrTypeCode, |
| 1544 | int attrLen, |
| 1545 | int attrFlags, |
| 1546 | ChannelBuffer message) { |
| 1547 | log.debug("BGP RX UPDATE Error from {}: Optional Attribute Error: {}", |
| 1548 | bgpSession.getRemoteAddress(), attrTypeCode); |
| 1549 | |
| 1550 | // |
| 1551 | // ERROR: Optional Attribute Error |
| 1552 | // |
| 1553 | // Send NOTIFICATION and close the connection |
| 1554 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1555 | int errorSubcode = |
| 1556 | UpdateMessageError.OPTIONAL_ATTRIBUTE_ERROR; |
| 1557 | ChannelBuffer data = |
| 1558 | prepareBgpUpdateNotificationDataPayload(attrTypeCode, attrLen, |
| 1559 | attrFlags, message); |
| 1560 | ChannelBuffer txMessage = |
| 1561 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1562 | data); |
| 1563 | ctx.getChannel().write(txMessage); |
| 1564 | bgpSession.closeSession(ctx); |
| 1565 | } |
| 1566 | |
| 1567 | /** |
| 1568 | * Applies the appropriate actions after detecting BGP UPDATE |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1569 | * Attribute Length Error: send NOTIFICATION and close the channel. |
| 1570 | * |
| 1571 | * @param bgpSession the BGP Session to use |
| 1572 | * @param ctx the Channel Handler Context |
| 1573 | * @param attrTypeCode the attribute type code |
| 1574 | * @param attrLen the attribute length (in octets) |
| 1575 | * @param attrFlags the attribute flags |
| 1576 | * @param message the message with the data |
| 1577 | */ |
| 1578 | private static void actionsBgpUpdateAttributeLengthError( |
| 1579 | BgpSession bgpSession, |
| 1580 | ChannelHandlerContext ctx, |
| 1581 | int attrTypeCode, |
| 1582 | int attrLen, |
| 1583 | int attrFlags, |
| 1584 | ChannelBuffer message) { |
| 1585 | log.debug("BGP RX UPDATE Error from {}: Attribute Length Error", |
| 1586 | bgpSession.getRemoteAddress()); |
| 1587 | |
| 1588 | // |
| 1589 | // ERROR: Attribute Length Error |
| 1590 | // |
| 1591 | // Send NOTIFICATION and close the connection |
| 1592 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1593 | int errorSubcode = UpdateMessageError.ATTRIBUTE_LENGTH_ERROR; |
| 1594 | ChannelBuffer data = |
| 1595 | prepareBgpUpdateNotificationDataPayload(attrTypeCode, attrLen, |
| 1596 | attrFlags, message); |
| 1597 | ChannelBuffer txMessage = |
| 1598 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1599 | data); |
| 1600 | ctx.getChannel().write(txMessage); |
| 1601 | bgpSession.closeSession(ctx); |
| 1602 | } |
| 1603 | |
| 1604 | /** |
| 1605 | * Applies the appropriate actions after detecting BGP UPDATE |
| 1606 | * Malformed AS_PATH Error: send NOTIFICATION and close the channel. |
| 1607 | * |
| 1608 | * @param bgpSession the BGP Session to use |
| 1609 | * @param ctx the Channel Handler Context |
| 1610 | */ |
| 1611 | private static void actionsBgpUpdateMalformedAsPath( |
| 1612 | BgpSession bgpSession, |
| 1613 | ChannelHandlerContext ctx) { |
| 1614 | log.debug("BGP RX UPDATE Error from {}: Malformed AS Path", |
| 1615 | bgpSession.getRemoteAddress()); |
| 1616 | |
| 1617 | // |
| 1618 | // ERROR: Malformed AS_PATH |
| 1619 | // |
| 1620 | // Send NOTIFICATION and close the connection |
| 1621 | int errorCode = UpdateMessageError.ERROR_CODE; |
| 1622 | int errorSubcode = UpdateMessageError.MALFORMED_AS_PATH; |
| 1623 | ChannelBuffer txMessage = |
| 1624 | BgpNotification.prepareBgpNotification(errorCode, errorSubcode, |
| 1625 | null); |
| 1626 | ctx.getChannel().write(txMessage); |
| 1627 | bgpSession.closeSession(ctx); |
| 1628 | } |
| 1629 | |
| 1630 | /** |
| 1631 | * Prepares BGP UPDATE Notification data payload. |
| 1632 | * |
| 1633 | * @param attrTypeCode the attribute type code |
| 1634 | * @param attrLen the attribute length (in octets) |
| 1635 | * @param attrFlags the attribute flags |
| 1636 | * @param message the message with the data |
| 1637 | * @return the buffer with the data payload for the BGP UPDATE Notification |
| 1638 | */ |
| 1639 | private static ChannelBuffer prepareBgpUpdateNotificationDataPayload( |
| 1640 | int attrTypeCode, |
| 1641 | int attrLen, |
| 1642 | int attrFlags, |
| 1643 | ChannelBuffer message) { |
| 1644 | // Compute the attribute length field octets |
| 1645 | boolean extendedLengthBit = ((0x10 & attrFlags) != 0); |
| 1646 | int attrLenOctets = 1; |
| 1647 | if (extendedLengthBit) { |
| 1648 | attrLenOctets = 2; |
| 1649 | } |
| 1650 | ChannelBuffer data = |
| 1651 | ChannelBuffers.buffer(attrLen + attrLenOctets + 1); |
| 1652 | data.writeByte(attrTypeCode); |
| 1653 | if (extendedLengthBit) { |
| 1654 | data.writeShort(attrLen); |
| 1655 | } else { |
| 1656 | data.writeByte(attrLen); |
| 1657 | } |
| 1658 | data.writeBytes(message, attrLen); |
| 1659 | return data; |
| 1660 | } |
Pavlin Radoslavov | c7648ee | 2014-12-19 16:20:33 -0800 | [diff] [blame] | 1661 | |
| 1662 | /** |
| 1663 | * Helper class for storing Multiprotocol Network Layer Reachability |
| 1664 | * information. |
| 1665 | */ |
| 1666 | private static final class MpNlri { |
| 1667 | private final int afi; |
| 1668 | private final int safi; |
| 1669 | private Ip4Address nextHop4; |
| 1670 | private Ip6Address nextHop6; |
| 1671 | private Collection<Ip4Prefix> nlri4 = new ArrayList<>(); |
| 1672 | private Collection<Ip6Prefix> nlri6 = new ArrayList<>(); |
| 1673 | |
| 1674 | /** |
| 1675 | * Constructor. |
| 1676 | * |
| 1677 | * @param afi the Address Family Identifier |
| 1678 | * @param safi the Subsequent Address Family Identifier |
| 1679 | */ |
| 1680 | private MpNlri(int afi, int safi) { |
| 1681 | this.afi = afi; |
| 1682 | this.safi = safi; |
| 1683 | } |
| 1684 | } |
| 1685 | |
| 1686 | /** |
| 1687 | * Helper class for storing decoded BGP routing information. |
| 1688 | */ |
| 1689 | private static final class DecodedBgpRoutes { |
| 1690 | private final Map<Ip4Prefix, BgpRouteEntry> addedUnicastRoutes4 = |
| 1691 | new HashMap<>(); |
| 1692 | private final Map<Ip6Prefix, BgpRouteEntry> addedUnicastRoutes6 = |
| 1693 | new HashMap<>(); |
| 1694 | private final Map<Ip4Prefix, BgpRouteEntry> deletedUnicastRoutes4 = |
| 1695 | new HashMap<>(); |
| 1696 | private final Map<Ip6Prefix, BgpRouteEntry> deletedUnicastRoutes6 = |
| 1697 | new HashMap<>(); |
| 1698 | } |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1699 | } |