BUG-3888 : fix comparing ASnumbers

[bgpcep.git] / bgp / rib-impl / src / main / java / org / opendaylight / protocol / bgp / rib / impl / StrictBGPPeerRegistry.java

diff --git a/bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/StrictBGPPeerRegistry.java b/bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/StrictBGPPeerRegistry.java
index 1e997a9c16ec4ace97585fcf9cbe2056745a3028..826d2f284a8aa409b9db9028f9da0ae44b671651 100644 (file)
--- a/bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/StrictBGPPeerRegistry.java
+++ b/bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/StrictBGPPeerRegistry.java
@@ -9,20 +9,26 @@
 package org.opendaylight.protocol.bgp.rib.impl;
 
 import com.google.common.base.MoreObjects;
+import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.Maps;
 import com.google.common.net.InetAddresses;
 import com.google.common.primitives.UnsignedInts;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
 import java.net.Inet4Address;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
+import java.util.List;
 import java.util.Map;
 import javax.annotation.concurrent.GuardedBy;
 import javax.annotation.concurrent.ThreadSafe;
+import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
 import org.opendaylight.protocol.bgp.parser.BGPError;
+import org.opendaylight.protocol.bgp.parser.impl.message.open.As4CapabilityHandler;
 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
 import org.opendaylight.protocol.bgp.rib.impl.spi.ReusableBGPPeer;
@@ -31,6 +37,12 @@ import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpAddress;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv6Address;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.BgpParameters;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.OptionalCapabilities;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.CParameters;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.CParametersBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.c.parameters.As4BytesCapability;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -90,15 +102,17 @@ public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
 
     @Override
     public synchronized BGPSessionListener getPeer(final IpAddress ip, final Ipv4Address sourceId,
-        final Ipv4Address remoteId, final AsNumber asNumber) throws BGPDocumentedException {
+        final Ipv4Address remoteId, final AsNumber remoteAsNumber, final Open openObj) throws BGPDocumentedException {
         Preconditions.checkNotNull(ip);
         Preconditions.checkNotNull(sourceId);
         Preconditions.checkNotNull(remoteId);
-        Preconditions.checkNotNull(asNumber);
+        Preconditions.checkNotNull(remoteAsNumber);
+
+        final BGPSessionPreferences prefs = getPeerPreferences(ip);
 
         checkPeerConfigured(ip);
 
-        final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId, asNumber);
+        final BGPSessionId currentConnection = new BGPSessionId(sourceId, remoteId, remoteAsNumber);
         final BGPSessionListener p = this.peers.get(ip);
 
         final BGPSessionId previousConnection = this.sessionIds.get(ip);
@@ -147,18 +161,58 @@ public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
                         ip, currentConnection),
                         BGPError.CEASE);
             }
-        } else {
-            if (!getPeerPreferences(ip).getMyAs().equals(asNumber)) {
-                LOG.warn("Unexpected remote AS number. Expecting {}, got {}", getPeerPreferences(ip).getMyAs(), asNumber);
-                throw new BGPDocumentedException("Peer AS number mismatch", BGPError.BAD_PEER_AS);
-            }
         }
+        validateAs(openObj, prefs);
 
         // Map session id to peer IP address
         this.sessionIds.put(ip, currentConnection);
         return p;
     }
 
+    private void validateAs(final Open openObj, final BGPSessionPreferences localPref) throws BGPDocumentedException {
+        final AsNumber remoteAs = AsNumberUtil.advertizedAsNumber(openObj);
+        if (!remoteAs.equals(localPref.getExpectedRemoteAs())) {
+            LOG.warn("Unexpected remote AS number. Expecting {}, got {}", remoteAs, localPref.getExpectedRemoteAs());
+            throw new BGPDocumentedException("Peer AS number mismatch", BGPError.BAD_PEER_AS);
+        }
+
+        // https://tools.ietf.org/html/rfc6286#section-2.2
+        if (openObj.getBgpIdentifier() != null && openObj.getBgpIdentifier().equals(localPref.getBgpId())) {
+            LOG.warn("Remote and local BGP Identifiers are the same: {}", openObj.getBgpIdentifier());
+            throw new BGPDocumentedException("Remote and local BGP Identifiers are the same.", BGPError.BAD_BGP_ID);
+        }
+        final List<BgpParameters> prefs = openObj.getBgpParameters();
+        if (prefs != null) {
+            if (getAs4BytesCapability(localPref.getParams()).isPresent() && !getAs4BytesCapability(prefs).isPresent()) {
+                throw new BGPDocumentedException("The peer must advertise AS4Bytes capability.", BGPError.UNSUPPORTED_CAPABILITY, serializeAs4BytesCapability(getAs4BytesCapability(localPref.getParams()).get()));
+            }
+            if (!prefs.containsAll(localPref.getParams())) {
+                LOG.info("BGP Open message session parameters differ, session still accepted.");
+            }
+        } else {
+            throw new BGPDocumentedException("Open message unacceptable. Check the configuration of BGP speaker.", BGPError.UNSPECIFIC_OPEN_ERROR);
+        }
+    }
+
+    private static Optional<As4BytesCapability> getAs4BytesCapability(final List<BgpParameters> prefs) {
+        for (final BgpParameters param : prefs) {
+            for (final OptionalCapabilities capa : param.getOptionalCapabilities()) {
+                final CParameters cParam = capa.getCParameters();
+                if (cParam.getAs4BytesCapability() != null) {
+                    return Optional.of(cParam.getAs4BytesCapability());
+                }
+            }
+        }
+        return Optional.absent();
+    }
+
+    private static byte[] serializeAs4BytesCapability(final As4BytesCapability as4Capability) {
+        final ByteBuf buffer = Unpooled.buffer(1 /*CODE*/ + 1 /*LENGTH*/ + Integer.SIZE / Byte.SIZE /*4 byte value*/);
+        final As4CapabilityHandler serializer = new As4CapabilityHandler();
+        serializer.serializeCapability(new CParametersBuilder().setAs4BytesCapability(as4Capability).build(), buffer);
+        return buffer.array();
+    }
+
     @Override
     public BGPSessionPreferences getPeerPreferences(final IpAddress ip) {
         Preconditions.checkNotNull(ip);
@@ -199,7 +253,8 @@ public final class StrictBGPPeerRegistry implements BGPPeerRegistry {
     }
 
     /**
-     * Session identifier that contains (source Bgp Id) -> (destination Bgp Id)
+     * Session identifier that contains (source Bgp Id) -> (destination Bgp Id) AsNumber is the remoteAs coming from
+     * remote Open message
      */
     private static final class BGPSessionId {