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.ArrayList;
  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.spi.MessageHandlerRegistry;
  21 import org.opendaylight.protocol.pcep.spi.MessageSerializer;
  22 import org.opendaylight.protocol.util.ByteArray;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Message;
  24 import org.slf4j.Logger;
  25 import org.slf4j.LoggerFactory;
  26
  27 import com.google.common.base.Preconditions;
  28 import com.google.common.primitives.UnsignedBytes;
  29
  30 /**
  31  * A PCEP message parser which also does validation.
  32  */
  33 public final class PCEPMessageFactory implements ProtocolMessageFactory<Message> {
  34
  35         private final static Logger logger = LoggerFactory.getLogger(PCEPMessageFactory.class);
  36
  37         private final static int TYPE_SIZE = 1; // bytes
  38
  39         private final static int LENGTH_SIZE = 2; // bytes
  40
  41         public final static int COMMON_HEADER_LENGTH = 4; // bytes
  42
  43         /**
  44          * Current supported version of PCEP.
  45          */
  46         public static final int PCEP_VERSION = 1;
  47
  48         private static final int VERSION_SF_LENGTH = 3;
  49
  50         private static final int VER_FLAGS_MF_LENGTH = 1;
  51         private static final int TYPE_F_LENGTH = 1;
  52         private static final int LENGTH_F_LENGTH = 2;
  53
  54         private static final int VER_FLAGS_MF_OFFSET = 0;
  55         private static final int TYPE_F_OFFSET = VER_FLAGS_MF_LENGTH + VER_FLAGS_MF_OFFSET;
  56         private static final int LENGTH_F_OFFSET = TYPE_F_LENGTH + TYPE_F_OFFSET;
  57
  58         private final MessageHandlerRegistry registry;
  59
  60         public PCEPMessageFactory(final MessageHandlerRegistry registry) {
  61                 this.registry = Preconditions.checkNotNull(registry);
  62         }
  63
  64         @Override
  65         public Message parse(final byte[] bytes) throws DeserializerException, DocumentedException {
  66                 Preconditions.checkArgument(bytes != null, "Bytes may not be null");
  67                 Preconditions.checkArgument(bytes.length != 0, "Bytes may not be empty");
  68
  69                 logger.trace("Attempt to parse message from bytes: {}", ByteArray.bytesToHexString(bytes));
  70
  71                 final int type = UnsignedBytes.toInt(bytes[1]);
  72
  73                 final int msgLength = ByteArray.bytesToInt(ByteArray.subByte(bytes, TYPE_SIZE + 1, LENGTH_SIZE));
  74
  75                 final byte[] msgBody = ByteArray.cutBytes(bytes, TYPE_SIZE + 1 + LENGTH_SIZE);
  76
  77                 if (msgBody.length != msgLength - COMMON_HEADER_LENGTH) {
  78                         throw new DeserializerException("Body size " + msgBody.length + " does not match header size "
  79                                         + (msgLength - COMMON_HEADER_LENGTH));
  80                 }
  81
  82                 final List<Message> errors = new ArrayList<>();
  83                 Message msg = null;
  84
  85                 try {
  86                         msg = this.registry.getMessageParser(type).parseMessage(msgBody, errors);
  87                 } catch (final PCEPDeserializerException e) {
  88                         logger.debug("Unexpected deserializer problem", e);
  89                         throw new DeserializerException(e.getMessage(), e);
  90                 }
  91
  92                 if (!errors.isEmpty()) {
  93                         // FIXME: we have a bunch of error messages, how can we send them back?
  94                 }
  95
  96                 logger.debug("Message was parsed. {}", msg);
  97                 return msg;
  98         }
  99
 100         @Override
 101         public byte[] put(final Message msg) {
 102                 if (msg == null) {
 103                         throw new IllegalArgumentException("PCEPMessage is mandatory.");
 104                 }
 105
 106                 final ByteBuf buf = new UnpooledByteBufAllocator(false).buffer();
 107
 108                 final MessageSerializer serializer = this.registry.getMessageSerializer(msg);
 109
 110                 serializer.serializeMessage(msg, buf);
 111
 112                 final byte[] msgBody = new byte[buf.readableBytes()];
 113
 114                 buf.getBytes(0, msgBody);
 115
 116                 final byte[] headerBytes = new byte[COMMON_HEADER_LENGTH];
 117
 118                 // msgVer_Flag
 119                 headerBytes[VER_FLAGS_MF_OFFSET] = (byte) (PCEP_VERSION << (Byte.SIZE - VERSION_SF_LENGTH));
 120
 121                 // msgType
 122                 headerBytes[TYPE_F_OFFSET] = (byte) serializer.getMessageType();
 123
 124                 // msgLength
 125                 System.arraycopy(ByteArray.intToBytes(msgBody.length + COMMON_HEADER_LENGTH), Integer.SIZE / Byte.SIZE - LENGTH_F_LENGTH,
 126                                 headerBytes, LENGTH_F_OFFSET, LENGTH_F_LENGTH);
 127
 128                 final byte[] retBytes = new byte[headerBytes.length + msgBody.length];
 129
 130                 ByteArray.copyWhole(headerBytes, retBytes, 0);
 131                 ByteArray.copyWhole(msgBody, retBytes, COMMON_HEADER_LENGTH);
 132
 133                 return retBytes;
 134         }
 135 }