pcep/spi/src/main/java/org/opendaylight/protocol/pcep/spi/AbstractMessageParser.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.spi;
   9
  10 import java.util.Arrays;
  11 import java.util.BitSet;
  12 import java.util.List;
  13
  14 import org.opendaylight.protocol.util.ByteArray;
  15 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.message.rev131007.PcerrBuilder;
  16 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Message;
  17 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Object;
  18 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.ObjectHeader;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcep.error.object.ErrorObjectBuilder;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.PcerrMessageBuilder;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.pcerr.message.ErrorsBuilder;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.pcerr.message.error.type.RequestCaseBuilder;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.pcerr.message.error.type.request._case.RequestBuilder;
  24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.pcerr.message.error.type.request._case.request.RpsBuilder;
  25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.rp.object.Rp;
  26 import org.slf4j.Logger;
  27 import org.slf4j.LoggerFactory;
  28
  29 import com.google.common.base.Preconditions;
  30 import com.google.common.collect.Lists;
  31 import com.google.common.primitives.UnsignedBytes;
  32
  33 public abstract class AbstractMessageParser implements MessageParser, MessageSerializer {
  34
  35         private static final Logger LOG = LoggerFactory.getLogger(AbstractMessageParser.class);
  36
  37         private static final int COMMON_OBJECT_HEADER_LENGTH = 4;
  38
  39         private static final int OC_F_LENGTH = 1;
  40         private static final int OT_FLAGS_MF_LENGTH = 1;
  41         private static final int OBJ_LENGTH_F_LENGTH = 2;
  42
  43         private static final int OT_SF_LENGTH = 4;
  44         private static final int FLAGS_SF_LENGTH = 4;
  45         /*
  46          * offsets of fields inside of multi-field in bits
  47          */
  48         private static final int OT_SF_OFFSET = 0;
  49         private static final int FLAGS_SF_OFFSET = OT_SF_OFFSET + OT_SF_LENGTH;
  50         /*
  51          * flags offsets inside multi-filed
  52          */
  53         private static final int P_FLAG_OFFSET = 6;
  54         private static final int I_FLAG_OFFSET = 7;
  55
  56         private final ObjectRegistry registry;
  57
  58         protected AbstractMessageParser(final ObjectRegistry registry) {
  59                 this.registry = Preconditions.checkNotNull(registry);
  60         }
  61
  62         protected byte[] serializeObject(final Object object) {
  63                 if (object == null) {
  64                         return new byte[] {};
  65                 }
  66                 return this.registry.serializeObject(object);
  67         }
  68
  69         private List<Object> parseObjects(final byte[] bytes) throws PCEPDeserializerException {
  70                 int offset = 0;
  71                 final List<Object> objs = Lists.newArrayList();
  72                 while (bytes.length - offset > 0) {
  73                         if (bytes.length - offset < COMMON_OBJECT_HEADER_LENGTH) {
  74                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
  75                                                 + COMMON_OBJECT_HEADER_LENGTH + ".");
  76                         }
  77
  78                         final int objClass = UnsignedBytes.toInt(bytes[offset]);
  79
  80                         offset += OC_F_LENGTH;
  81
  82                         final int objType = UnsignedBytes.toInt(ByteArray.copyBitsRange(bytes[offset], OT_SF_OFFSET, OT_SF_LENGTH));
  83
  84                         final byte[] flagsBytes = { ByteArray.copyBitsRange(bytes[offset], FLAGS_SF_OFFSET, FLAGS_SF_LENGTH) };
  85
  86                         final BitSet flags = ByteArray.bytesToBitSet(flagsBytes);
  87
  88                         offset += OT_FLAGS_MF_LENGTH;
  89
  90                         final int objLength = ByteArray.bytesToInt(ByteArray.subByte(bytes, offset, OBJ_LENGTH_F_LENGTH));
  91
  92                         if (bytes.length - offset < objLength - COMMON_OBJECT_HEADER_LENGTH) {
  93                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
  94                                                 + objLength + ".");
  95                         }
  96
  97                         offset += OBJ_LENGTH_F_LENGTH;
  98
  99                         // copy bytes for deeper parsing
 100                         final byte[] bytesToPass = ByteArray.subByte(bytes, offset, objLength - COMMON_OBJECT_HEADER_LENGTH);
 101
 102                         offset += objLength - COMMON_OBJECT_HEADER_LENGTH;
 103
 104                         final ObjectHeader header = new ObjectHeaderImpl(flags.get(P_FLAG_OFFSET), flags.get(I_FLAG_OFFSET));
 105
 106                         // parseObject is required to return null for P=0 errored objects
 107                         final Object o = this.registry.parseObject(objClass, objType, header, bytesToPass);
 108                         if (o != null) {
 109                                 objs.add(o);
 110                         }
 111                 }
 112
 113                 return objs;
 114         }
 115
 116         public static Message createErrorMsg(final PCEPErrors e) {
 117                 final PCEPErrorMapping maping = PCEPErrorMapping.getInstance();
 118                 return new PcerrBuilder().setPcerrMessage(
 119                                 new PcerrMessageBuilder().setErrors(
 120                                                 Arrays.asList(new ErrorsBuilder().setErrorObject(
 121                                                                 new ErrorObjectBuilder().setType(maping.getFromErrorsEnum(e).type).setValue(
 122                                                                                 maping.getFromErrorsEnum(e).value).build()).build())).build()).build();
 123         }
 124
 125         public static Message createErrorMsg(final PCEPErrors e, final Rp rp) {
 126                 final PCEPErrorMapping maping = PCEPErrorMapping.getInstance();
 127                 return new PcerrBuilder().setPcerrMessage(
 128                                 new PcerrMessageBuilder().setErrorType(
 129                                                 new RequestCaseBuilder().setRequest(
 130                                                                 new RequestBuilder().setRps(Lists.newArrayList(new RpsBuilder().setRp(rp).build())).build()).build()).setErrors(
 131                                                                                 Arrays.asList(new ErrorsBuilder().setErrorObject(
 132                                                                                                 new ErrorObjectBuilder().setType(maping.getFromErrorsEnum(e).type).setValue(
 133                                                                                                                 maping.getFromErrorsEnum(e).value).build()).build())).build()).build();
 134         }
 135
 136         protected abstract Message validate(final List<Object> objects, final List<Message> errors) throws PCEPDeserializerException;
 137
 138         @Override
 139         public final Message parseMessage(final byte[] buffer, final List<Message> errors) throws PCEPDeserializerException {
 140                 Preconditions.checkNotNull(buffer, "Buffer may not be null");
 141
 142                 // Parse objects first
 143                 final List<Object> objs = parseObjects(buffer);
 144
 145                 // Run validation
 146                 return validate(objs, errors);
 147         }
 148 }