[ONOS-2600] Implementation of basic BGP protocol message parsing factories
Change-Id: Ie8ff454a36c9bff2a785ea198ed47ce5f60666cd
diff --git a/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BGPMessageVer4.java b/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BGPMessageVer4.java
new file mode 100755
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+++ b/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BGPMessageVer4.java
@@ -0,0 +1,109 @@
+/*
+ * Copyright 2015 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.bgpio.protocol.ver4;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.onosproject.bgpio.exceptions.BGPParseException;
+import org.onosproject.bgpio.protocol.BGPFactories;
+import org.onosproject.bgpio.protocol.BGPMessage;
+import org.onosproject.bgpio.protocol.BGPMessageReader;
+import org.onosproject.bgpio.types.BGPErrorType;
+import org.onosproject.bgpio.types.BGPHeader;
+import org.onosproject.bgpio.util.Validation;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Provides BGP messages.
+ */
+public abstract class BGPMessageVer4 {
+
+ protected static final Logger log = LoggerFactory.getLogger(BGPFactories.class);
+
+ static final byte OPEN_MSG_TYPE = 0x1;
+ static final byte KEEPALIVE_MSG_TYPE = 0x4;
+ static final byte UPDATE_MSG_TYPE = 0x2;
+ static final byte NOTIFICATION_MSG_TYPE = 0x3;
+ static final int MINIMUM_COMMON_HEADER_LENGTH = 19;
+ static final int HEADER_AND_MSG_LEN = 18;
+ static final int MAXIMUM_PACKET_LENGTH = 4096;
+
+ public static final BGPMessageVer4.Reader READER = new Reader();
+
+ /**
+ * Reader class for reading BGP messages from channel buffer.
+ *
+ */
+ static class Reader implements BGPMessageReader<BGPMessage> {
+ @Override
+ public BGPMessage readFrom(ChannelBuffer cb, BGPHeader bgpHeader)
+ throws BGPParseException {
+
+ if (cb.readableBytes() < MINIMUM_COMMON_HEADER_LENGTH) {
+ log.error("Packet should have minimum length.");
+ Validation.validateLen(BGPErrorType.MESSAGE_HEADER_ERROR, BGPErrorType.BAD_MESSAGE_LENGTH,
+ cb.readableBytes());
+ }
+ if (cb.readableBytes() > MAXIMUM_PACKET_LENGTH) {
+ log.error("Packet length should not exceed {}.", MAXIMUM_PACKET_LENGTH);
+ Validation.validateLen(BGPErrorType.MESSAGE_HEADER_ERROR, BGPErrorType.BAD_MESSAGE_LENGTH,
+ cb.readableBytes());
+ }
+ try {
+ // fixed value property version == 4
+ byte[] marker = new byte[BGPHeader.MARKER_LENGTH];
+ cb.readBytes(marker, 0, BGPHeader.MARKER_LENGTH);
+ bgpHeader.setMarker(marker);
+ for (int i = 0; i < BGPHeader.MARKER_LENGTH; i++) {
+ if (marker[i] != (byte) 0xff) {
+ throw new BGPParseException(BGPErrorType.MESSAGE_HEADER_ERROR,
+ BGPErrorType.CONNECTION_NOT_SYNCHRONIZED, null);
+ }
+ }
+ short length = cb.readShort();
+ if (length != (cb.readableBytes() + HEADER_AND_MSG_LEN)) {
+ Validation.validateLen(BGPErrorType.MESSAGE_HEADER_ERROR, BGPErrorType.BAD_MESSAGE_LENGTH, length);
+ }
+ bgpHeader.setLength(length);
+ byte type = cb.readByte();
+ bgpHeader.setType(type);
+ log.debug("Reading update message of type " + type);
+
+ int len = length - MINIMUM_COMMON_HEADER_LENGTH;
+ switch (type) {
+ case OPEN_MSG_TYPE:
+ log.debug("OPEN MESSAGE is received");
+ return BGPOpenMsgVer4.READER.readFrom(cb.readBytes(len), bgpHeader);
+ case KEEPALIVE_MSG_TYPE:
+ log.debug("KEEPALIVE MESSAGE is received");
+ return BGPKeepaliveMsgVer4.READER.readFrom(cb.readBytes(len), bgpHeader);
+ case UPDATE_MSG_TYPE:
+ log.debug("UPDATE MESSAGE is received");
+ // TODO: Update message version 4
+ case NOTIFICATION_MSG_TYPE:
+ log.debug("NOTIFICATION MESSAGE is received");
+ return BGPNotificationMsgVer4.READER.readFrom(cb.readBytes(len), bgpHeader);
+ default:
+ Validation.validateType(BGPErrorType.MESSAGE_HEADER_ERROR, BGPErrorType.BAD_MESSAGE_TYPE, type);
+ return null;
+ }
+ } catch (IndexOutOfBoundsException e) {
+ throw new BGPParseException(BGPErrorType.MESSAGE_HEADER_ERROR, BGPErrorType.BAD_MESSAGE_LENGTH, null);
+ }
+ }
+ }
+}
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