pcep/impl/src/main/java/org/opendaylight/protocol/pcep/impl/PCEPMessageFactory.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.protocol.pcep.impl;
   9
  10 import io.netty.buffer.ByteBuf;
  11 import io.netty.buffer.UnpooledByteBufAllocator;
  12
  13 import java.util.Arrays;
  14 import java.util.List;
  15
  16 import org.opendaylight.protocol.framework.DeserializerException;
  17 import org.opendaylight.protocol.framework.DocumentedException;
  18 import org.opendaylight.protocol.framework.ProtocolMessageFactory;
  19 import org.opendaylight.protocol.pcep.PCEPDeserializerException;
  20 import org.opendaylight.protocol.pcep.PCEPDocumentedException;
  21 import org.opendaylight.protocol.pcep.spi.HandlerRegistry;
  22 import org.opendaylight.protocol.pcep.spi.MessageSerializer;
  23 import org.opendaylight.protocol.util.ByteArray;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Message;
  25 import org.slf4j.Logger;
  26 import org.slf4j.LoggerFactory;
  27
  28 import com.google.common.base.Preconditions;
  29 import com.google.common.primitives.UnsignedBytes;
  30
  31 /**
  32  * A PCEP message parser which also does validation.
  33  */
  34 public final class PCEPMessageFactory implements ProtocolMessageFactory<Message> {
  35
  36         private final static Logger logger = LoggerFactory.getLogger(PCEPMessageFactory.class);
  37
  38         private final static int TYPE_SIZE = 1; // bytes
  39
  40         private final static int LENGTH_SIZE = 2; // bytes
  41
  42         public final static int COMMON_HEADER_LENGTH = 4; // bytes
  43
  44         /**
  45          * Current supported version of PCEP.
  46          */
  47         public static final int PCEP_VERSION = 1;
  48
  49         private static final int VERSION_SF_LENGTH = 3;
  50
  51         private final HandlerRegistry registry;
  52
  53         private static final int VER_FLAGS_MF_LENGTH = 1;
  54         private static final int TYPE_F_LENGTH = 1;
  55         private static final int LENGTH_F_LENGTH = 2;
  56
  57         private static final int VER_FLAGS_MF_OFFSET = 0;
  58         private static final int TYPE_F_OFFSET = VER_FLAGS_MF_LENGTH + VER_FLAGS_MF_OFFSET;
  59         private static final int LENGTH_F_OFFSET = TYPE_F_LENGTH + TYPE_F_OFFSET;
  60
  61         public PCEPMessageFactory() {
  62                 this.registry = HandlerRegistryImpl.INSTANCE;
  63         }
  64
  65         @Override
  66         public List<Message> parse(final byte[] bytes) throws DeserializerException, DocumentedException {
  67                 Preconditions.checkArgument(bytes != null, "Bytes may not be null");
  68                 Preconditions.checkArgument(bytes.length != 0, "Bytes may not be empty");
  69
  70                 logger.trace("Attempt to parse message from bytes: {}", ByteArray.bytesToHexString(bytes));
  71
  72                 final int type = UnsignedBytes.toInt(bytes[1]);
  73
  74                 final int msgLength = ByteArray.bytesToInt(ByteArray.subByte(bytes, TYPE_SIZE + 1, LENGTH_SIZE));
  75
  76                 final byte[] msgBody = ByteArray.cutBytes(bytes, TYPE_SIZE + 1 + LENGTH_SIZE);
  77
  78                 if (msgBody.length != msgLength - COMMON_HEADER_LENGTH) {
  79                         throw new DeserializerException("Body size " + msgBody.length + " does not match header size "
  80                                         + (msgLength - COMMON_HEADER_LENGTH));
  81                 }
  82
  83                 Message msg = null;
  84
  85                 try {
  86                         msg = this.registry.getMessageParser(type).parseMessage(msgBody);
  87                 } catch (final PCEPDeserializerException e) {
  88                         logger.debug("Unexpected deserializer problem", e);
  89                         throw new DeserializerException(e.getMessage(), e);
  90                 } catch (final PCEPDocumentedException e) {
  91                         logger.debug("Documented deserializer problem", e);
  92                         throw new DocumentedException(e.getMessage(), e);
  93                 }
  94                 logger.debug("Message was parsed. {}", msg);
  95                 return Arrays.asList(msg);
  96         }
  97
  98         @Override
  99         public byte[] put(final Message msg) {
 100                 if (msg == null) {
 101                         throw new IllegalArgumentException("PCEPMessage is mandatory.");
 102                 }
 103
 104                 final ByteBuf buf = new UnpooledByteBufAllocator(false).buffer();
 105
 106                 final MessageSerializer serializer = this.registry.getMessageSerializer(msg);
 107
 108                 serializer.serializeMessage(msg, buf);
 109
 110                 final byte[] msgBody = buf.array();
 111
 112                 final byte[] headerBytes = new byte[COMMON_HEADER_LENGTH];
 113
 114                 // msgVer_Flag
 115                 headerBytes[VER_FLAGS_MF_OFFSET] = (byte) (PCEP_VERSION << (Byte.SIZE - VERSION_SF_LENGTH));
 116
 117                 // msgType
 118                 headerBytes[TYPE_F_OFFSET] = (byte) serializer.getMessageType();
 119
 120                 // msgLength
 121                 System.arraycopy(ByteArray.intToBytes(msgBody.length), Integer.SIZE / Byte.SIZE - LENGTH_F_LENGTH, headerBytes, LENGTH_F_OFFSET,
 122                                 LENGTH_F_LENGTH);
 123
 124                 final byte[] retBytes = new byte[headerBytes.length + msgBody.length];
 125
 126                 ByteArray.copyWhole(headerBytes, retBytes, 0);
 127                 ByteArray.copyWhole(msgBody, retBytes, PCEPMessageHeader.COMMON_HEADER_LENGTH);
 128
 129                 return retBytes;
 130         }
 131 }