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