098d940e966ff9fc1527333af509597b09aba4e7
[bgpcep.git] / bgp / parser-impl / src / main / java / org / opendaylight / protocol / bgp / parser / impl / message / open / LlGracefulCapabilityHandler.java
1 /*
2  * Copyright (c) 2018 AT&T Intellectual Property. 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.bgp.parser.impl.message.open;
9
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static java.util.Objects.requireNonNull;
12
13 import io.netty.buffer.ByteBuf;
14 import io.netty.buffer.Unpooled;
15 import java.util.ArrayList;
16 import java.util.List;
17 import org.opendaylight.protocol.bgp.parser.spi.AddressFamilyRegistry;
18 import org.opendaylight.protocol.bgp.parser.spi.CapabilityParser;
19 import org.opendaylight.protocol.bgp.parser.spi.CapabilitySerializer;
20 import org.opendaylight.protocol.bgp.parser.spi.CapabilityUtil;
21 import org.opendaylight.protocol.bgp.parser.spi.SubsequentAddressFamilyRegistry;
22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.open.message.bgp.parameters.optional.capabilities.CParameters;
23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev180329.open.message.bgp.parameters.optional.capabilities.CParametersBuilder;
24 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.CParameters1;
25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.CParameters1Builder;
26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.LlGracefulRestartCapability;
27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.LlGracefulRestartCapabilityBuilder;
28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.ll.graceful.restart.capability.Tables;
29 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev180329.mp.capabilities.ll.graceful.restart.capability.TablesBuilder;
30 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev180329.AddressFamily;
31 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev180329.SubsequentAddressFamily;
32 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.uint24.rev200104.Uint24;
33 import org.opendaylight.yangtools.yang.common.Uint32;
34 import org.slf4j.Logger;
35 import org.slf4j.LoggerFactory;
36
37 public final class LlGracefulCapabilityHandler implements CapabilityParser, CapabilitySerializer {
38     public static final int CODE = 71;
39
40     private static final Logger LOG = LoggerFactory.getLogger(LlGracefulCapabilityHandler.class);
41
42     // size of AFI (16 bits) and SAFI (8bits) fields in bytes
43     private static final int AFI_SAFI_SIZE = 3;
44
45     private static final int AFI_FLAGS_SIZE = 1;
46     private static final int STALE_TIME_SIZE = 3;
47
48     private static final int PER_TABLE_SIZE = AFI_SAFI_SIZE + AFI_FLAGS_SIZE + STALE_TIME_SIZE;
49
50     private static final int MAX_STALE_TIME = 16777215;
51     private static final byte AFI_FLAG_FORWARDING_STATE = (byte) 0x80;
52
53     private final AddressFamilyRegistry afiReg;
54     private final SubsequentAddressFamilyRegistry safiReg;
55
56     public LlGracefulCapabilityHandler(final AddressFamilyRegistry afiReg,
57                                        final SubsequentAddressFamilyRegistry safiReg) {
58         this.afiReg = requireNonNull(afiReg);
59         this.safiReg = requireNonNull(safiReg);
60     }
61
62     @Override
63     public CParameters parseCapability(final ByteBuf buffer) {
64         final List<Tables> tables = new ArrayList<>();
65
66         while (buffer.isReadable()) {
67             final short afival = buffer.readShort();
68             final Class<? extends AddressFamily> afi = this.afiReg.classForFamily(afival);
69             if (afi == null) {
70                 LOG.debug("Ignoring GR capability for unknown address family {}", afival);
71                 buffer.skipBytes(PER_TABLE_SIZE - 2);
72                 continue;
73             }
74
75             final byte safival = buffer.readByte();
76             final Class<? extends SubsequentAddressFamily> safi = this.safiReg.classForFamily(safival);
77             if (safi == null) {
78                 LOG.debug("Ignoring GR capability for unknown subsequent address family {}", safival);
79                 buffer.skipBytes(1);
80                 continue;
81             }
82
83             final byte afiFlags = buffer.readByte();
84             final int staleTime = buffer.readUnsignedMedium();
85             final Tables table = new TablesBuilder()
86                     .setAfi(afi)
87                     .setSafi(safi)
88                     .setAfiFlags(new Tables.AfiFlags(Boolean.valueOf(afiFlags == AFI_FLAG_FORWARDING_STATE)))
89                     .setLongLivedStaleTime(new Uint24(Uint32.valueOf(staleTime)))
90                     .build();
91             tables.add(table);
92         }
93         return new CParametersBuilder()
94                 .addAugmentation(CParameters1.class, new CParameters1Builder()
95                         .setLlGracefulRestartCapability(new LlGracefulRestartCapabilityBuilder()
96                                 .setTables(tables)
97                                 .build())
98                         .build())
99                 .build();
100     }
101
102     @Override
103     public void serializeCapability(final CParameters capability, final ByteBuf byteAggregator) {
104         final CParameters1 aug = capability.augmentation(CParameters1.class);
105         if (aug != null) {
106             final LlGracefulRestartCapability cap = aug.getLlGracefulRestartCapability();
107             if (cap != null) {
108                 CapabilityUtil.formatCapability(CODE, serializeCapability(cap), byteAggregator);
109             }
110         }
111     }
112
113     private ByteBuf serializeCapability(final LlGracefulRestartCapability cap) {
114         final List<Tables> tables = cap.getTables();
115         if (tables == null || tables.isEmpty()) {
116             return Unpooled.EMPTY_BUFFER;
117         }
118
119         final ByteBuf buffer = Unpooled.buffer(PER_TABLE_SIZE * tables.size());
120         for (Tables table : tables) {
121             final Class<? extends AddressFamily> afi = table.getAfi();
122             final Class<? extends SubsequentAddressFamily> safi = table.getSafi();
123             final Integer afival = this.afiReg.numberForClass(afi);
124             checkArgument(afival != null, "Unhandled address family %s", afi);
125             buffer.writeShort(afival);
126             final Integer safival = this.safiReg.numberForClass(safi);
127             checkArgument(safival != null, "Unhandled subsequent address family %s", safi);
128             buffer.writeByte(safival);
129             if (table.getAfiFlags() != null && table.getAfiFlags().isForwardingState()) {
130                 buffer.writeByte(AFI_FLAG_FORWARDING_STATE);
131             } else {
132                 buffer.writeByte(0);
133             }
134             final Uint24 staleTime = table.getLongLivedStaleTime();
135             final int timeval = staleTime != null ? staleTime.getValue().intValue() : 0;
136             checkArgument(timeval >= 0 && timeval <= MAX_STALE_TIME, "Restart time is %s", staleTime);
137             buffer.writeMedium(timeval);
138         }
139         return buffer;
140     }
141 }