Merge pull request #89 from BarbarossaTM/fix/AdjRIBOutWithAddPath

Fix AdjRIBOut with AddPath and add whole bunch of tests of AdjRIBOut

route/route.go

@@ -28,7 +28,7 @@ type Route struct {
 	ecmpPaths uint
 }
 
-// NewRoute generates a new route with paths p
+// NewRoute generates a new route with path p
 func NewRoute(pfx net.Prefix, p *Path) *Route {
 	r := &Route{
 		pfx: pfx,
@@ -43,6 +43,23 @@ func NewRoute(pfx net.Prefix, p *Path) *Route {
 	return r
 }
 
+// NewRouteAddPath generates a new route with paths p
+func NewRouteAddPath(pfx net.Prefix, p []*Path) *Route {
+	r := &Route{
+		pfx: pfx,
+	}
+
+	if p == nil {
+		r.paths = make([]*Path, 0)
+		return r
+	}
+
+	for _, path := range p {
+		r.paths = append(r.paths, path)
+	}
+	return r
+}
+
 // Copy returns a copy of route r
 func (r *Route) Copy() *Route {
 	if r == nil {

routingtable/adjRIBOut/BUILD.bazel

@@ -19,10 +19,17 @@ go_library(
 
 go_test(
     name = "go_default_test",
-    srcs = ["path_id_manager_test.go"],
+    srcs = [
+        "adj_rib_out_test.go",
+        "path_id_manager_test.go",
+    ],
     embed = [":go_default_library"],
     deps = [
+        "//net:go_default_library",
+        "//protocols/bgp/types:go_default_library",
         "//route:go_default_library",
+        "//routingtable:go_default_library",
+        "//routingtable/filter:go_default_library",
         "//vendor/github.com/stretchr/testify/assert:go_default_library",
     ],
 )

routingtable/adjRIBOut/adj_rib_out.go

@@ -47,6 +47,9 @@ func (a *AdjRIBOut) RouteCount() int64 {
 // AddPath adds path p to prefix `pfx`
 func (a *AdjRIBOut) AddPath(pfx bnet.Prefix, p *route.Path) error {
 	if !routingtable.ShouldPropagateUpdate(pfx, p, a.neighbor) {
+		if a.neighbor.CapAddPathRX {
+			a.removePathsForPrefix(pfx)
+		}
 		return nil
 	}
 
@@ -55,6 +58,7 @@ func (a *AdjRIBOut) AddPath(pfx bnet.Prefix, p *route.Path) error {
 		return nil
 	}
 
+	// If the neighbor is an eBGP peer and not a Route Server client modify ASPath and Next Hop
 	p = p.Copy()
 	if !a.neighbor.IBGP && !a.neighbor.RouteServerClient {
 		p.BGPPath.Prepend(a.neighbor.LocalASN, 1)
@@ -130,6 +134,25 @@ func (a *AdjRIBOut) RemovePath(pfx bnet.Prefix, p *route.Path) bool {
 	return true
 }
 
+func (a *AdjRIBOut) removePathsForPrefix(pfx bnet.Prefix) bool {
+	// We were called before a.AddPath() had a lock, so we need to lock here and release it
+	// after the get to prevent a dead lock as RemovePath() will acquire a lock itself!
+	a.mu.Lock()
+	r := a.rt.Get(pfx)
+	a.mu.Unlock()
+
+	// If no path with this prefix is present, we're done
+	if r == nil {
+		return false
+	}
+
+	for _, path := range r.Paths() {
+		a.RemovePath(pfx, path)
+	}
+
+	return true
+}
+
 func (a *AdjRIBOut) isOwnPath(p *route.Path) bool {
 	if p.Type != a.neighbor.Type {
 		return false