Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 1 | /* |
Ray Milkey | 34c9590 | 2015-04-15 09:47:53 -0700 | [diff] [blame] | 2 | * Copyright 2014-2015 Open Networking Laboratory |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 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 | */ |
Jonathan Hart | 41349e9 | 2015-02-09 14:14:02 -0800 | [diff] [blame] | 16 | package org.onosproject.routing.bgp; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 17 | |
| 18 | import org.jboss.netty.buffer.ChannelBuffer; |
| 19 | import org.jboss.netty.buffer.ChannelBuffers; |
| 20 | import org.jboss.netty.channel.ChannelHandlerContext; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 21 | import org.slf4j.Logger; |
| 22 | import org.slf4j.LoggerFactory; |
| 23 | |
| 24 | /** |
| 25 | * A class for handling BGP NOTIFICATION messages. |
| 26 | */ |
| 27 | final class BgpNotification { |
| 28 | private static final Logger log = |
| 29 | LoggerFactory.getLogger(BgpNotification.class); |
| 30 | |
| 31 | /** |
| 32 | * Default constructor. |
| 33 | * <p> |
| 34 | * The constructor is private to prevent creating an instance of |
| 35 | * this utility class. |
| 36 | */ |
| 37 | private BgpNotification() { |
| 38 | } |
| 39 | |
| 40 | /** |
| 41 | * Processes BGP NOTIFICATION message. |
| 42 | * |
| 43 | * @param bgpSession the BGP Session to use |
| 44 | * @param ctx the Channel Handler Context |
| 45 | * @param message the message to process |
| 46 | */ |
| 47 | static void processBgpNotification(BgpSession bgpSession, |
| 48 | ChannelHandlerContext ctx, |
| 49 | ChannelBuffer message) { |
| 50 | int minLength = |
| 51 | BgpConstants.BGP_NOTIFICATION_MIN_LENGTH - BgpConstants.BGP_HEADER_LENGTH; |
| 52 | if (message.readableBytes() < minLength) { |
| 53 | log.debug("BGP RX NOTIFICATION Error from {}: " + |
| 54 | "Message length {} too short. Must be at least {}", |
Pavlin Radoslavov | 8a36ce3 | 2015-01-28 12:26:57 -0800 | [diff] [blame] | 55 | bgpSession.remoteInfo().address(), |
| 56 | message.readableBytes(), minLength); |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 57 | // |
| 58 | // ERROR: Bad Message Length |
| 59 | // |
| 60 | // NOTE: We do NOT send NOTIFICATION in response to a notification |
| 61 | return; |
| 62 | } |
| 63 | |
| 64 | // |
| 65 | // Parse the NOTIFICATION message |
| 66 | // |
| 67 | int errorCode = message.readUnsignedByte(); |
| 68 | int errorSubcode = message.readUnsignedByte(); |
| 69 | int dataLength = message.readableBytes(); |
| 70 | |
| 71 | log.debug("BGP RX NOTIFICATION message from {}: Error Code {} " + |
| 72 | "Error Subcode {} Data Length {}", |
Pavlin Radoslavov | 8a36ce3 | 2015-01-28 12:26:57 -0800 | [diff] [blame] | 73 | bgpSession.remoteInfo().address(), errorCode, errorSubcode, |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 74 | dataLength); |
| 75 | |
| 76 | // |
| 77 | // NOTE: If the peer sent a NOTIFICATION, we leave it to the peer to |
| 78 | // close the connection. |
| 79 | // |
| 80 | |
| 81 | // Start the Session Timeout timer |
| 82 | bgpSession.restartSessionTimeoutTimer(ctx); |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Prepares BGP NOTIFICATION message. |
| 87 | * |
| 88 | * @param errorCode the BGP NOTIFICATION Error Code |
| 89 | * @param errorSubcode the BGP NOTIFICATION Error Subcode if applicable, |
| 90 | * otherwise BgpConstants.Notifications.ERROR_SUBCODE_UNSPECIFIC |
| 91 | * @param data the BGP NOTIFICATION Data if applicable, otherwise null |
| 92 | * @return the message to transmit (BGP header included) |
| 93 | */ |
| 94 | static ChannelBuffer prepareBgpNotification(int errorCode, |
| 95 | int errorSubcode, |
| 96 | ChannelBuffer data) { |
| 97 | ChannelBuffer message = |
| 98 | ChannelBuffers.buffer(BgpConstants.BGP_MESSAGE_MAX_LENGTH); |
| 99 | |
| 100 | // |
| 101 | // Prepare the NOTIFICATION message payload |
| 102 | // |
| 103 | message.writeByte(errorCode); |
| 104 | message.writeByte(errorSubcode); |
| 105 | if (data != null) { |
| 106 | message.writeBytes(data); |
| 107 | } |
| 108 | return BgpMessage.prepareBgpMessage(BgpConstants.BGP_TYPE_NOTIFICATION, |
| 109 | message); |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * Prepares BGP NOTIFICATION message: Bad Message Length. |
| 114 | * |
| 115 | * @param length the erroneous Length field |
| 116 | * @return the message to transmit (BGP header included) |
| 117 | */ |
| 118 | static ChannelBuffer prepareBgpNotificationBadMessageLength(int length) { |
Jonathan Hart | 41349e9 | 2015-02-09 14:14:02 -0800 | [diff] [blame] | 119 | int errorCode = BgpConstants.Notifications.MessageHeaderError.ERROR_CODE; |
| 120 | int errorSubcode = BgpConstants.Notifications.MessageHeaderError.BAD_MESSAGE_LENGTH; |
Pavlin Radoslavov | 80f3e18 | 2014-12-15 10:46:18 -0800 | [diff] [blame] | 121 | ChannelBuffer data = ChannelBuffers.buffer(2); |
| 122 | data.writeShort(length); |
| 123 | |
| 124 | return prepareBgpNotification(errorCode, errorSubcode, data); |
| 125 | } |
| 126 | } |