support AGGREGATOR and AS4_AGGREGATOR conversion

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

3 files changed, 74 insertions, 15 deletions

diff --git a/packet/bgp/bgp.go b/packet/bgp/bgp.go
index 8a793720..9d6678d3 100644
--- a/packet/bgp/bgp.go
+++ b/packet/bgp/bgp.go
@@ -4439,7 +4439,7 @@ func NewPathAttributeAtomicAggregate() *PathAttributeAtomicAggregate {
 
 type PathAttributeAggregatorParam struct {
 	AS      uint32
-	askind  reflect.Kind
+	Askind  reflect.Kind
 	Address net.IP
 }
 
@@ -4461,18 +4461,18 @@ func (p *PathAttributeAggregator) DecodeFromBytes(data []byte) error {
 	if len(p.PathAttribute.Value) == 6 {
 		p.Value.AS = uint32(binary.BigEndian.Uint16(p.PathAttribute.Value[0:2]))
 		p.Value.Address = p.PathAttribute.Value[2:]
-		p.Value.askind = reflect.Uint16
+		p.Value.Askind = reflect.Uint16
 	} else {
 		p.Value.AS = binary.BigEndian.Uint32(p.PathAttribute.Value[0:4])
 		p.Value.Address = p.PathAttribute.Value[4:]
-		p.Value.askind = reflect.Uint32
+		p.Value.Askind = reflect.Uint32
 	}
 	return nil
 }
 
 func (p *PathAttributeAggregator) Serialize() ([]byte, error) {
 	var buf []byte
-	switch p.Value.askind {
+	switch p.Value.Askind {
 	case reflect.Uint16:
 		buf = make([]byte, 6)
 		binary.BigEndian.PutUint16(buf, uint16(p.Value.AS))
@@ -4513,7 +4513,7 @@ func NewPathAttributeAggregator(as interface{}, address string) *PathAttributeAg
 		},
 		Value: PathAttributeAggregatorParam{
 			AS:      uint32(v.Uint()),
-			askind:  v.Kind(),
+			Askind:  v.Kind(),
 			Address: net.ParseIP(address).To4(),
 		},
 	}
diff --git a/server/fsm.go b/server/fsm.go
index e0fb53c2..e80c6512 100644
--- a/server/fsm.go
+++ b/server/fsm.go
@@ -634,18 +634,23 @@ func (h *FSMHandler) recvMessageWithError() (*FsmMsg, error) {
 				} else {
 					// FIXME: we should use the original message for bmp/mrt
 					table.UpdatePathAttrs4ByteAs(body)
-					fmsg.PathList = table.ProcessMessage(m, h.fsm.peerInfo, fmsg.timestamp)
-					id := h.fsm.pConf.Config.NeighborAddress
-					policyMutex.RLock()
-					for _, path := range fmsg.PathList {
-						if path.IsEOR() {
-							continue
-						}
-						if h.fsm.policy.ApplyPolicy(id, table.POLICY_DIRECTION_IN, path, nil) == nil {
-							path.Filter(id, table.POLICY_DIRECTION_IN)
+					err := table.UpdatePathAggregator4ByteAs(body)
+					if err == nil {
+						fmsg.PathList = table.ProcessMessage(m, h.fsm.peerInfo, fmsg.timestamp)
+						id := h.fsm.pConf.Config.NeighborAddress
+						policyMutex.RLock()
+						for _, path := range fmsg.PathList {
+							if path.IsEOR() {
+								continue
+							}
+							if h.fsm.policy.ApplyPolicy(id, table.POLICY_DIRECTION_IN, path, nil) == nil {
+								path.Filter(id, table.POLICY_DIRECTION_IN)
+							}
 						}
+						policyMutex.RUnlock()
+					} else {
+						fmsg.MsgData = err
 					}
-					policyMutex.RUnlock()
 				}
 				fmsg.payload = make([]byte, len(headerBuf)+len(bodyBuf))
 				copy(fmsg.payload, headerBuf)
@@ -1009,6 +1014,7 @@ func (h *FSMHandler) sendMessageloop() error {
 				"Data":  m,
 			}).Debug("update for 2byte AS peer")
 			table.UpdatePathAttrs2ByteAs(m.Body.(*bgp.BGPUpdate))
+			table.UpdatePathAggregator2ByteAs(m.Body.(*bgp.BGPUpdate))
 		}
 		b, err := m.Serialize()
 		if err != nil {
diff --git a/table/message.go b/table/message.go
index 5cf9b5b6..68801e73 100644
--- a/table/message.go
+++ b/table/message.go
@@ -20,6 +20,7 @@ import (
 	log "github.com/Sirupsen/logrus"
 	"github.com/osrg/gobgp/packet/bgp"
 	"hash/fnv"
+	"reflect"
 )
 
 func UpdatePathAttrs2ByteAs(msg *bgp.BGPUpdate) error {
@@ -198,6 +199,58 @@ func UpdatePathAttrs4ByteAs(msg *bgp.BGPUpdate) error {
 	return nil
 }
 
+func UpdatePathAggregator2ByteAs(msg *bgp.BGPUpdate) {
+	as := uint32(0)
+	var addr string
+	for _, attr := range msg.PathAttributes {
+		switch attr.(type) {
+		case *bgp.PathAttributeAggregator:
+			agg := attr.(*bgp.PathAttributeAggregator)
+			agg.Value.Askind = reflect.Uint16
+			if agg.Value.AS > (1<<16)-1 {
+				as = agg.Value.AS
+				addr = agg.Value.Address.String()
+				agg.Value.AS = bgp.AS_TRANS
+			}
+		}
+	}
+	if as != 0 {
+		msg.PathAttributes = append(msg.PathAttributes, bgp.NewPathAttributeAs4Aggregator(as, addr))
+	}
+}
+
+func UpdatePathAggregator4ByteAs(msg *bgp.BGPUpdate) error {
+	var aggAttr *bgp.PathAttributeAggregator
+	var agg4Attr *bgp.PathAttributeAs4Aggregator
+	agg4AttrPos := 0
+	for i, attr := range msg.PathAttributes {
+		switch attr.(type) {
+		case *bgp.PathAttributeAggregator:
+			attr := attr.(*bgp.PathAttributeAggregator)
+			if attr.Value.Askind == reflect.Uint16 {
+				aggAttr = attr
+				aggAttr.Value.Askind = reflect.Uint32
+			}
+		case *bgp.PathAttributeAs4Aggregator:
+			agg4Attr = attr.(*bgp.PathAttributeAs4Aggregator)
+			agg4AttrPos = i
+		}
+	}
+	if aggAttr == nil && agg4Attr == nil {
+		return nil
+	}
+
+	if aggAttr == nil && agg4Attr != nil {
+		return bgp.NewMessageError(bgp.BGP_ERROR_UPDATE_MESSAGE_ERROR, bgp.BGP_ERROR_SUB_MALFORMED_ATTRIBUTE_LIST, nil, "AS4 AGGREGATOR attribute exists, but AGGREGATOR doesn't")
+	}
+
+	if agg4Attr != nil {
+		msg.PathAttributes = append(msg.PathAttributes[:agg4AttrPos], msg.PathAttributes[agg4AttrPos+1:]...)
+		aggAttr.Value.AS = agg4Attr.Value.AS
+	}
+	return nil
+}
+
 func createUpdateMsgFromPath(path *Path, msg *bgp.BGPMessage) *bgp.BGPMessage {
 	rf := path.GetRouteFamily()