policy: add AsPathLength match

1 files changed, 29 insertions, 0 deletions

diff --git a/table/path.go b/table/path.go
index 29d8a92d..a1f87391 100644
--- a/table/path.go
+++ b/table/path.go
@@ -33,6 +33,7 @@ type Path interface {
 	getPathAttr(bgp.BGPAttrType) (int, bgp.PathAttributeInterface)
 	updatePathAttrs(global *config.Global, peer *config.Neighbor)
 	GetRouteFamily() bgp.RouteFamily
+	GetAsPathLen() int
 	setSource(source *PeerInfo)
 	GetSource() *PeerInfo
 	GetSourceAs() uint32
@@ -332,6 +333,34 @@ func (pi *PathDefault) getPrefix() string {
 	return pi.nlri.String()
 }
 
+// return total length of AS_PATH whose type is AS_SEQ or AS_SET
+func (pd *PathDefault) GetAsPathLen() int {
+
+	aslen := func(p *bgp.As4PathParam) int {
+		if p.Type == bgp.BGP_ASPATH_ATTR_TYPE_SEQ || p.Type == bgp.BGP_ASPATH_ATTR_TYPE_SET {
+			return p.ASLen()
+		}
+		return 0
+	}
+
+	var length int = 0
+	if _, attr := pd.getPathAttr(bgp.BGP_ATTR_TYPE_AS_PATH); attr != nil {
+		aspath := attr.(*bgp.PathAttributeAsPath)
+		for _, paramIf := range aspath.Value {
+			segment := paramIf.(*bgp.As4PathParam)
+			length += aslen(segment)
+		}
+
+	} else {
+		_, attr := pd.getPathAttr(bgp.BGP_ATTR_TYPE_AS4_PATH)
+		aspath := attr.(*bgp.PathAttributeAs4Path)
+		for _, segment := range aspath.Value {
+			length += aslen(segment)
+		}
+	}
+	return length
+}
+
 // create Path object based on route family
 func CreatePath(source *PeerInfo, nlri bgp.AddrPrefixInterface, attrs []bgp.PathAttributeInterface, isWithdraw bool, now time.Time) (Path, error) {