bgp/concepts/src/main/java/org/opendaylight/bgp/concepts/RouteDistinguisherUtil.java

   1 /*
   2  * Copyright (c) 2016 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.bgp.concepts;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import com.google.common.annotations.VisibleForTesting;
  14 import io.netty.buffer.ByteBuf;
  15 import java.util.regex.Pattern;
  16 import org.eclipse.jdt.annotation.NonNull;
  17 import org.eclipse.jdt.annotation.Nullable;
  18 import org.opendaylight.protocol.util.Ipv4Util;
  19 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4AddressNoZone;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev200120.RdAs;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev200120.RdIpv4;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev200120.RdTwoOctetAs;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev200120.RouteDistinguisher;
  24 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  25 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerNode;
  26 import org.slf4j.Logger;
  27 import org.slf4j.LoggerFactory;
  28
  29 /**
  30  * Utility class for of RouteDistinguisher serialization and parsing.
  31  * https://tools.ietf.org/html/rfc4364#section-4.2
  32  */
  33 public final class RouteDistinguisherUtil {
  34     public static final int RD_LENGTH = 8;
  35
  36     private static final Logger LOG = LoggerFactory.getLogger(RouteDistinguisherUtil.class);
  37     @VisibleForTesting
  38     static final char SEPARATOR = ':';
  39
  40     // Route descriptor types
  41     private static final int RD_AS_2BYTE = 0;
  42     private static final int RD_IPV4     = 1;
  43     private static final int RD_AS_4BYTE = 2;
  44
  45     // Patterns for parsing String representation
  46     private static final Pattern AS_2BYTE_PATTERN =
  47         Pattern.compile("0:"
  48             + "([0-9]|[1-9][0-9]|[1-9][0-9][0-9]|[1-9][0-9][0-9][0-9]|"
  49             + "[1-5][0-9][0-9][0-9][0-9]|6[0-4][0-9][0-9][0-9]|"
  50             + "65[0-4][0-9][0-9]|655[0-2][0-9]|6553[0-5])"
  51             + ":"
  52             + "([0-9]|[1-9][0-9]|[1-9][0-9][0-9]|[1-9][0-9][0-9][0-9]|"
  53             + "[1-9][0-9][0-9][0-9][0-9]|[1-9][0-9][0-9][0-9][0-9][0-9]|"
  54             + "[1-9][0-9][0-9][0-9][0-9][0-9][0-9]|[1-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|"
  55             + "[1-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|[1-3][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|"
  56             + "4[0-1][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|42[0-8][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|"
  57             + "429[0-3][0-9][0-9][0-9][0-9][0-9][0-9]|4294[0-8][0-9][0-9][0-9][0-9][0-9]|"
  58             + "42949[0-5][0-9][0-9][0-9][0-9]|429496[0-6][0-9][0-9][0-9]|4294967[0-1][0-9][0-9]|"
  59             + "42949672[0-8][0-9]|429496729[0-5])");
  60
  61     private static final Pattern IPV4_PATTERN =
  62         Pattern.compile("((([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\\.){3}"
  63             + "([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5]))"
  64             + ":"
  65             + "([0-9]|[1-9][0-9]|[1-9][0-9][0-9]|[1-9][0-9][0-9][0-9]|"
  66             + "[1-5][0-9][0-9][0-9][0-9]|6[0-4][0-9][0-9][0-9]|"
  67             + "65[0-4][0-9][0-9]|655[0-2][0-9]|6553[0-5])");
  68
  69     private static final Pattern AS_4BYTE_PATTERN =
  70         Pattern.compile("([0-9]|[1-9][0-9]|[1-9][0-9][0-9]|[1-9][0-9][0-9][0-9]|"
  71             + "[1-9][0-9][0-9][0-9][0-9]|[1-9][0-9][0-9][0-9][0-9][0-9]|"
  72             + "[1-9][0-9][0-9][0-9][0-9][0-9][0-9]|[1-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|"
  73             + "[1-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|[1-3][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|"
  74             + "4[0-1][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|42[0-8][0-9][0-9][0-9][0-9][0-9][0-9][0-9]|"
  75             + "429[0-3][0-9][0-9][0-9][0-9][0-9][0-9]|4294[0-8][0-9][0-9][0-9][0-9][0-9]|"
  76             + "42949[0-5][0-9][0-9][0-9][0-9]|429496[0-6][0-9][0-9][0-9]|4294967[0-1][0-9][0-9]|"
  77             + "42949672[0-8][0-9]|429496729[0-5])"
  78             + ":"
  79             + "([0-9]|[1-9][0-9]|[1-9][0-9][0-9]|[1-9][0-9][0-9][0-9]|"
  80             + "[1-5][0-9][0-9][0-9][0-9]|6[0-4][0-9][0-9][0-9]|"
  81             + "65[0-4][0-9][0-9]|655[0-2][0-9]|6553[0-5])");
  82
  83
  84     private RouteDistinguisherUtil() {
  85         // Hidden on purpose
  86     }
  87
  88     /**
  89      * Serializes route distinguisher according to type and writes into ByteBuf.
  90      */
  91     public static void serializeRouteDistinquisher(final RouteDistinguisher distinguisher,
  92             final ByteBuf byteAggregator) {
  93         requireNonNull(distinguisher);
  94         checkState(byteAggregator != null && byteAggregator.isWritable(RD_LENGTH),
  95                 "Cannot write Route Distinguisher to provided buffer.");
  96         if (distinguisher.getRdTwoOctetAs() != null) {
  97             serialize(byteAggregator, distinguisher.getRdTwoOctetAs());
  98         } else if (distinguisher.getRdAs() != null) {
  99             serialize(byteAggregator, distinguisher.getRdAs());
 100         } else if (distinguisher.getRdIpv4() != null) {
 101             serialize(byteAggregator, distinguisher.getRdIpv4());
 102         } else {
 103             LOG.warn("Unable to serialize Route Distinguisher. Invalid RD value found. RD={}", distinguisher);
 104         }
 105     }
 106
 107     private static void serialize(final ByteBuf buf, final RdAs as) {
 108         final String value = as.getValue();
 109         final int first = findSeparator(value, 0);
 110         checkNoColon(value, first);
 111
 112         buf.writeShort(RD_AS_4BYTE);
 113         buf.writeInt(Integer.parseUnsignedInt(value.substring(0, first)));
 114         buf.writeShort(Integer.parseUnsignedInt(value.substring(first + 1)));
 115     }
 116
 117     private static void serialize(final ByteBuf buf, final RdTwoOctetAs as) {
 118         final String value = as.getValue();
 119         final int first = findSeparator(value, 0) + 1;
 120         final int second = findSeparator(value, first);
 121         checkNoColon(value, second);
 122
 123         buf.writeShort(RD_AS_2BYTE);
 124         buf.writeShort(Integer.parseUnsignedInt(value.substring(first, second)));
 125         buf.writeInt(Integer.parseUnsignedInt(value.substring(second + 1)));
 126     }
 127
 128     private static void serialize(final ByteBuf buf, final RdIpv4 ipv4) {
 129         final String value = ipv4.getValue();
 130         final int first = findSeparator(value, 0);
 131         checkNoColon(value, first);
 132
 133         buf.writeShort(RD_IPV4);
 134         buf.writeBytes(Ipv4Util.bytesForAddress(new Ipv4AddressNoZone(value.substring(0, first))));
 135         buf.writeShort(Integer.parseUnsignedInt(value.substring(first + 1)));
 136     }
 137
 138     private static int findSeparator(final String str, final int fromIndex) {
 139         final int found = str.indexOf(SEPARATOR, fromIndex);
 140         checkState(found != -1, "Invalid route distinguiser %s", str);
 141         return found;
 142     }
 143
 144     private static void checkNoColon(final String str, final int lastIndex) {
 145         checkState(str.indexOf(SEPARATOR, lastIndex + 1) == -1, "Invalid route distinguiser %s", str);
 146     }
 147
 148     /**
 149      * Parses three types of route distinguisher from given ByteBuf.
 150      */
 151     public static @NonNull RouteDistinguisher parseRouteDistinguisher(final ByteBuf buffer) {
 152         checkState(buffer != null && buffer.isReadable(RD_LENGTH),
 153                 "Cannot read Route Distinguisher from provided buffer.");
 154         final int type = buffer.readUnsignedShort();
 155         switch (type) {
 156             case RD_AS_2BYTE:
 157                 return new RouteDistinguisher(new RdTwoOctetAs(new StringBuilder()
 158                     .append(type)
 159                     .append(SEPARATOR)
 160                     .append(buffer.readUnsignedShort())
 161                     .append(SEPARATOR)
 162                     .append(buffer.readUnsignedInt())
 163                     .toString()));
 164             case RD_IPV4:
 165                 return new RouteDistinguisher(new RdIpv4(new StringBuilder()
 166                     .append(Ipv4Util.addressForByteBuf(buffer).getValue())
 167                     .append(SEPARATOR)
 168                     .append(buffer.readUnsignedShort())
 169                     .toString()));
 170             case RD_AS_4BYTE:
 171                 return new RouteDistinguisher(new RdAs(new StringBuilder()
 172                     .append(buffer.readUnsignedInt())
 173                     .append(SEPARATOR)
 174                     .append(buffer.readUnsignedShort())
 175                     .toString()));
 176             default:
 177                 // now that this RD type is not supported, we want to read the remain 6 bytes
 178                 // in order to get the byte index correct
 179                 final var sb = new StringBuilder();
 180                 for (int i = 0; i < 6; i++) {
 181                     sb.append("0x").append(Integer.toHexString(buffer.readByte() & 0xFF)).append(' ');
 182                 }
 183                 LOG.debug("Invalid Route Distinguisher: type={}, rawRouteDistinguisherValue={}", type, sb);
 184                 throw new IllegalArgumentException("Invalid Route Distinguisher type " + type);
 185         }
 186     }
 187
 188     public static @NonNull RouteDistinguisher parseRouteDistinguisher(final String defaultValue) {
 189         if (AS_2BYTE_PATTERN.matcher(defaultValue).matches()) {
 190             return new RouteDistinguisher(new RdTwoOctetAs(defaultValue));
 191         } else if (IPV4_PATTERN.matcher(defaultValue).matches()) {
 192             return new RouteDistinguisher(new RdIpv4(defaultValue));
 193         } else if (AS_4BYTE_PATTERN.matcher(defaultValue).matches()) {
 194             return new RouteDistinguisher(new RdAs(defaultValue));
 195         } else {
 196             throw new IllegalArgumentException("Cannot create Route Distinguisher from " + defaultValue);
 197         }
 198     }
 199
 200     public static @Nullable RouteDistinguisher extractRouteDistinguisher(final DataContainerNode route,
 201             final NodeIdentifier rdNid) {
 202         final var rdNode = route.childByArg(rdNid);
 203         return rdNode == null ? null : parseRouteDistinguisher((String) rdNode.body());
 204     }
 205 }