* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
-
package org.opendaylight.protocol.bgp.parser.impl.message;
-import java.util.Arrays;
-import java.util.List;
+import com.google.common.base.Preconditions;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import java.util.List;
import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
import org.opendaylight.protocol.bgp.parser.BGPError;
import org.opendaylight.protocol.bgp.parser.BGPParsingException;
-import org.opendaylight.protocol.bgp.parser.impl.BGPMessageFactoryImpl;
-import org.opendaylight.protocol.bgp.parser.impl.message.update.PathAttributeParser;
+import org.opendaylight.protocol.bgp.parser.impl.message.update.AsPathAttributeParser;
+import org.opendaylight.protocol.bgp.parser.impl.message.update.NextHopAttributeParser;
+import org.opendaylight.protocol.bgp.parser.impl.message.update.OriginAttributeParser;
+import org.opendaylight.protocol.bgp.parser.spi.AttributeRegistry;
import org.opendaylight.protocol.bgp.parser.spi.MessageParser;
-import org.opendaylight.protocol.concepts.Ipv4Util;
+import org.opendaylight.protocol.bgp.parser.spi.MessageSerializer;
+import org.opendaylight.protocol.bgp.parser.spi.MessageUtil;
+import org.opendaylight.protocol.bgp.parser.spi.PeerSpecificParserConstraint;
import org.opendaylight.protocol.util.ByteArray;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Prefix;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.Update;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.UpdateBuilder;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.update.NlriBuilder;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.update.PathAttributes;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130918.update.WithdrawnRoutesBuilder;
+import org.opendaylight.protocol.util.ByteBufWriteUtil;
+import org.opendaylight.protocol.util.Ipv4Util;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Prefix;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.UpdateBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.Attributes;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.update.message.Nlri;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.update.message.NlriBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.update.message.WithdrawnRoutes;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.update.message.WithdrawnRoutesBuilder;
+import org.opendaylight.yangtools.yang.binding.Notification;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* LENGTH fields, that denote the length of the fields with variable length, have fixed SIZE.
- *
+ *
* @see <a href="http://tools.ietf.org/html/rfc4271#section-4.3">BGP-4 Update Message Format</a>
- *
*/
-public class BGPUpdateMessageParser implements MessageParser {
- public static final BGPUpdateMessageParser PARSER = new BGPUpdateMessageParser();
-
- private static Logger logger = LoggerFactory.getLogger(BGPUpdateMessageParser.class);
-
- /**
- * Size of the withdrawn_routes_length field, in bytes.
- */
- public static final int WITHDRAWN_ROUTES_LENGTH_SIZE = 2;
-
- /**
- * Size of the total_path_attr_length field, in bytes.
- */
- public static final int TOTAL_PATH_ATTR_LENGTH_SIZE = 2;
-
- // Constructors -------------------------------------------------------
- private BGPUpdateMessageParser() {
-
- }
-
- // Getters & setters --------------------------------------------------
-
- @Override
- public Update parseMessage(final byte[] bytes, final int msgLength) throws BGPDocumentedException {
- if (bytes == null || bytes.length == 0) {
- throw new IllegalArgumentException("Byte array cannot be null or empty.");
- }
- logger.trace("Started parsing of update message: {}", Arrays.toString(bytes));
-
- int byteOffset = 0;
-
- final int withdrawnRoutesLength = ByteArray.bytesToInt(ByteArray.subByte(bytes, byteOffset, WITHDRAWN_ROUTES_LENGTH_SIZE));
- byteOffset += WITHDRAWN_ROUTES_LENGTH_SIZE;
-
- final UpdateBuilder eventBuilder = new UpdateBuilder();
-
- if (withdrawnRoutesLength > 0) {
- final List<Ipv4Prefix> withdrawnRoutes = Ipv4Util.prefixListForBytes(ByteArray.subByte(bytes, byteOffset, withdrawnRoutesLength));
- byteOffset += withdrawnRoutesLength;
- eventBuilder.setWithdrawnRoutes(new WithdrawnRoutesBuilder().setWithdrawnRoutes(withdrawnRoutes).build());
- }
-
- final int totalPathAttrLength = ByteArray.bytesToInt(ByteArray.subByte(bytes, byteOffset, TOTAL_PATH_ATTR_LENGTH_SIZE));
- byteOffset += TOTAL_PATH_ATTR_LENGTH_SIZE;
-
- if (withdrawnRoutesLength + totalPathAttrLength + BGPMessageFactoryImpl.COMMON_HEADER_LENGTH > msgLength) {
- throw new BGPDocumentedException("Message length inconsistent with withdrawn router length.", BGPError.MALFORMED_ATTR_LIST);
- }
-
- if (withdrawnRoutesLength == 0 && totalPathAttrLength == 0) {
- return eventBuilder.build();
- }
-
- try {
- if (totalPathAttrLength > 0) {
- final PathAttributes pathAttributes = PathAttributeParser.parseAttribute(ByteArray.subByte(bytes, byteOffset,
- totalPathAttrLength));
- byteOffset += totalPathAttrLength;
- eventBuilder.setPathAttributes(pathAttributes);
- }
- } catch (final BGPParsingException e) {
- logger.warn("Could not parse BGP attributes: {}", e.getMessage(), e);
- throw new BGPDocumentedException("Could not parse BGP attributes.", BGPError.MALFORMED_ATTR_LIST);
- }
-
- final List<Ipv4Prefix> nlri = Ipv4Util.prefixListForBytes(ByteArray.subByte(bytes, byteOffset, bytes.length - byteOffset));
- eventBuilder.setNlri(new NlriBuilder().setNlri(nlri).build());
-
- logger.trace("Update message was parsed.");
- return eventBuilder.build();
- }
+public final class BGPUpdateMessageParser implements MessageParser, MessageSerializer {
+
+ private static final Logger LOG = LoggerFactory.getLogger(BGPUpdateMessageParser.class);
+
+ public static final int TYPE = 2;
+
+ private static final int WITHDRAWN_ROUTES_LENGTH_SIZE = 2;
+
+ private static final int TOTAL_PATH_ATTR_LENGTH_SIZE = 2;
+
+ private final AttributeRegistry reg;
+
+ public BGPUpdateMessageParser(final AttributeRegistry reg) {
+ this.reg = Preconditions.checkNotNull(reg);
+ }
+
+ @Override
+ public Update parseMessageBody(final ByteBuf buffer, final int messageLength) throws BGPDocumentedException {
+ return parseMessageBody(buffer, messageLength, null);
+ }
+
+ @Override
+ public void serializeMessage(final Notification message, final ByteBuf bytes) {
+ Preconditions.checkArgument(message instanceof Update, "Message needs to be of type Update");
+ final Update update = (Update) message;
+
+ final ByteBuf messageBody = Unpooled.buffer();
+ final WithdrawnRoutes withdrawnRoutes = update.getWithdrawnRoutes();
+ if (withdrawnRoutes != null) {
+ final ByteBuf withdrawnRoutesBuf = Unpooled.buffer();
+ for (final Ipv4Prefix prefix : withdrawnRoutes.getWithdrawnRoutes()) {
+ ByteBufWriteUtil.writeMinimalPrefix(prefix, withdrawnRoutesBuf);
+ }
+ messageBody.writeShort(withdrawnRoutesBuf.writerIndex());
+ messageBody.writeBytes(withdrawnRoutesBuf);
+ } else {
+ messageBody.writeZero(WITHDRAWN_ROUTES_LENGTH_SIZE);
+ }
+ if (update.getAttributes() != null) {
+ final ByteBuf pathAttributesBuf = Unpooled.buffer();
+ this.reg.serializeAttribute(update.getAttributes(), pathAttributesBuf);
+ messageBody.writeShort(pathAttributesBuf.writerIndex());
+ messageBody.writeBytes(pathAttributesBuf);
+ } else {
+ messageBody.writeZero(TOTAL_PATH_ATTR_LENGTH_SIZE);
+ }
+ final Nlri nlri = update.getNlri();
+ if (nlri != null && nlri.getNlri() !=null) {
+ for (final Ipv4Prefix prefix : nlri.getNlri()) {
+ ByteBufWriteUtil.writeMinimalPrefix(prefix, messageBody);
+ }
+ }
+ MessageUtil.formatMessage(TYPE, messageBody, bytes);
+ }
+
+ /**
+ * Parse Update message from buffer.
+ * Calls {@link #checkMandatoryAttributesPresence(Update)} to check for presence of mandatory attributes.
+ *
+ * @param buffer Encoded BGP message in ByteBuf
+ * @param messageLength Length of the BGP message
+ * @param constraint Peer specific constraints
+ * @return Parsed Update message body
+ * @throws BGPDocumentedException
+ */
+ @Override
+ public Update parseMessageBody(final ByteBuf buffer, final int messageLength, final PeerSpecificParserConstraint constraint)
+ throws BGPDocumentedException {
+ Preconditions.checkArgument(buffer != null && buffer.isReadable(), "Buffer cannot be null or empty.");
+
+ final UpdateBuilder builder = new UpdateBuilder();
+
+ final int withdrawnRoutesLength = buffer.readUnsignedShort();
+ if (withdrawnRoutesLength > 0) {
+ // TODO handle NLRI with multiple paths - requires modified yang data model
+ final List<Ipv4Prefix> withdrawnRoutes = Ipv4Util.prefixListForBytes(ByteArray.readBytes(buffer, withdrawnRoutesLength));
+ builder.setWithdrawnRoutes(new WithdrawnRoutesBuilder().setWithdrawnRoutes(withdrawnRoutes).build());
+ }
+ final int totalPathAttrLength = buffer.readUnsignedShort();
+
+ if (withdrawnRoutesLength == 0 && totalPathAttrLength == 0) {
+ return builder.build();
+ }
+ if (totalPathAttrLength > 0) {
+ try {
+ final Attributes attributes = this.reg.parseAttributes(buffer.readSlice(totalPathAttrLength), constraint);
+ builder.setAttributes(attributes);
+ } catch (final RuntimeException | BGPParsingException e) {
+ // Catch everything else and turn it into a BGPDocumentedException
+ throw new BGPDocumentedException("Could not parse BGP attributes.", BGPError.MALFORMED_ATTR_LIST, e);
+ }
+ }
+ final List<Ipv4Prefix> nlri = Ipv4Util.prefixListForBytes(ByteArray.readAllBytes(buffer));
+ if (!nlri.isEmpty()) {
+ // TODO handle NLRI with multiple paths - requires modified yang data model
+ builder.setNlri(new NlriBuilder().setNlri(nlri).build());
+ }
+ final Update msg = builder.build();
+ checkMandatoryAttributesPresence(msg);
+ LOG.debug("BGP Update message was parsed {}.", msg);
+ return msg;
+ }
+
+ /**
+ * Check for presence of well known mandatory path attributes
+ * ORIGIN, AS_PATH and NEXT_HOP in Update message
+ *
+ * @param message Update message
+ * @throws BGPDocumentedException
+ */
+ private static void checkMandatoryAttributesPresence(final Update message) throws BGPDocumentedException {
+ Preconditions.checkNotNull(message, "Update message cannot be null");
+
+ final Attributes attrs = message.getAttributes();
+
+ if (message.getNlri() != null) {
+ if (attrs == null || attrs.getCNextHop() == null) {
+ throw new BGPDocumentedException(BGPError.MANDATORY_ATTR_MISSING_MSG + "NEXT_HOP",
+ BGPError.WELL_KNOWN_ATTR_MISSING,
+ new byte[] { NextHopAttributeParser.TYPE });
+ }
+ }
+
+ if (MessageUtil.isAnyNlriPresent(message)) {
+ if (attrs == null || attrs.getOrigin() == null) {
+ throw new BGPDocumentedException(BGPError.MANDATORY_ATTR_MISSING_MSG + "ORIGIN",
+ BGPError.WELL_KNOWN_ATTR_MISSING,
+ new byte[] { OriginAttributeParser.TYPE });
+ }
+
+ if (attrs == null || attrs.getAsPath() == null) {
+ throw new BGPDocumentedException(BGPError.MANDATORY_ATTR_MISSING_MSG + "AS_PATH",
+ BGPError.WELL_KNOWN_ATTR_MISSING,
+ new byte[] { AsPathAttributeParser.TYPE });
+ }
+ }
+ }
}
Code Review / bgpcep.git / blobdiff