| /* |
| * Copyright 2014 Open Networking Laboratory |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.onosproject.sdnip.bgp; |
| |
| import java.util.concurrent.CountDownLatch; |
| |
| import org.jboss.netty.buffer.ChannelBuffer; |
| import org.jboss.netty.channel.Channel; |
| import org.jboss.netty.channel.ChannelHandlerContext; |
| import org.jboss.netty.handler.codec.frame.FrameDecoder; |
| import org.onlab.packet.Ip4Address; |
| |
| /** |
| * Class for handling the decoding of the BGP messages at the remote |
| * BGP peer session. |
| */ |
| class TestBgpPeerFrameDecoder extends FrameDecoder { |
| int remoteBgpVersion; // 1 octet |
| long remoteAs; // 2 octets |
| long remoteHoldtime; // 2 octets |
| Ip4Address remoteBgpIdentifier; // 4 octets -> IPv4 address |
| |
| final CountDownLatch receivedOpenMessageLatch = new CountDownLatch(1); |
| final CountDownLatch receivedKeepaliveMessageLatch = new CountDownLatch(1); |
| |
| @Override |
| protected Object decode(ChannelHandlerContext ctx, |
| Channel channel, |
| ChannelBuffer buf) throws Exception { |
| // Test for minimum length of the BGP message |
| if (buf.readableBytes() < BgpConstants.BGP_HEADER_LENGTH) { |
| // No enough data received |
| return null; |
| } |
| |
| // |
| // Mark the current buffer position in case we haven't received |
| // the whole message. |
| // |
| buf.markReaderIndex(); |
| |
| // |
| // Read and check the BGP message Marker field: it must be all ones |
| // |
| byte[] marker = new byte[BgpConstants.BGP_HEADER_MARKER_LENGTH]; |
| buf.readBytes(marker); |
| for (int i = 0; i < marker.length; i++) { |
| if (marker[i] != (byte) 0xff) { |
| // ERROR: Connection Not Synchronized. Close the channel. |
| ctx.getChannel().close(); |
| return null; |
| } |
| } |
| |
| // |
| // Read and check the BGP message Length field |
| // |
| int length = buf.readUnsignedShort(); |
| if ((length < BgpConstants.BGP_HEADER_LENGTH) || |
| (length > BgpConstants.BGP_MESSAGE_MAX_LENGTH)) { |
| // ERROR: Bad Message Length. Close the channel. |
| ctx.getChannel().close(); |
| return null; |
| } |
| |
| // |
| // Test whether the rest of the message is received: |
| // So far we have read the Marker (16 octets) and the |
| // Length (2 octets) fields. |
| // |
| int remainingMessageLen = |
| length - BgpConstants.BGP_HEADER_MARKER_LENGTH - 2; |
| if (buf.readableBytes() < remainingMessageLen) { |
| // No enough data received |
| buf.resetReaderIndex(); |
| return null; |
| } |
| |
| // |
| // Read the BGP message Type field, and process based on that type |
| // |
| int type = buf.readUnsignedByte(); |
| remainingMessageLen--; // Adjust after reading the type |
| ChannelBuffer message = buf.readBytes(remainingMessageLen); |
| |
| // |
| // Process the remaining of the message based on the message type |
| // |
| switch (type) { |
| case BgpConstants.BGP_TYPE_OPEN: |
| processBgpOpen(ctx, message); |
| break; |
| case BgpConstants.BGP_TYPE_UPDATE: |
| // NOTE: Not used as part of the test, because ONOS does not |
| // originate UPDATE messages. |
| break; |
| case BgpConstants.BGP_TYPE_NOTIFICATION: |
| // NOTE: Not used as part of the testing (yet) |
| break; |
| case BgpConstants.BGP_TYPE_KEEPALIVE: |
| processBgpKeepalive(ctx, message); |
| break; |
| default: |
| // ERROR: Bad Message Type. Close the channel. |
| ctx.getChannel().close(); |
| return null; |
| } |
| |
| return null; |
| } |
| |
| /** |
| * Processes BGP OPEN message. |
| * |
| * @param ctx the Channel Handler Context. |
| * @param message the message to process. |
| */ |
| private void processBgpOpen(ChannelHandlerContext ctx, |
| ChannelBuffer message) { |
| int minLength = |
| BgpConstants.BGP_OPEN_MIN_LENGTH - BgpConstants.BGP_HEADER_LENGTH; |
| if (message.readableBytes() < minLength) { |
| // ERROR: Bad Message Length. Close the channel. |
| ctx.getChannel().close(); |
| return; |
| } |
| |
| // |
| // Parse the OPEN message |
| // |
| remoteBgpVersion = message.readUnsignedByte(); |
| remoteAs = message.readUnsignedShort(); |
| remoteHoldtime = message.readUnsignedShort(); |
| remoteBgpIdentifier = |
| Ip4Address.valueOf((int) message.readUnsignedInt()); |
| // Optional Parameters |
| int optParamLen = message.readUnsignedByte(); |
| if (message.readableBytes() < optParamLen) { |
| // ERROR: Bad Message Length. Close the channel. |
| ctx.getChannel().close(); |
| return; |
| } |
| message.readBytes(optParamLen); // NOTE: data ignored |
| |
| // BGP OPEN message successfully received |
| receivedOpenMessageLatch.countDown(); |
| } |
| |
| /** |
| * Processes BGP KEEPALIVE message. |
| * |
| * @param ctx the Channel Handler Context. |
| * @param message the message to process. |
| */ |
| private void processBgpKeepalive(ChannelHandlerContext ctx, |
| ChannelBuffer message) { |
| if (message.readableBytes() + BgpConstants.BGP_HEADER_LENGTH != |
| BgpConstants.BGP_KEEPALIVE_EXPECTED_LENGTH) { |
| // ERROR: Bad Message Length. Close the channel. |
| ctx.getChannel().close(); |
| return; |
| } |
| // BGP KEEPALIVE message successfully received |
| receivedKeepaliveMessageLatch.countDown(); |
| } |
| } |