Merge branch '1.8'

net/bridge.go

@@ -1,6 +1,9 @@
 package net
 
 import (
+	"fmt"
+
+	"github.com/Sirupsen/logrus"
 	"github.com/vishvananda/netlink"
 )
 
@@ -51,3 +54,35 @@ func isDatapath(link netlink.Link) bool {
 		return false
 	}
 }
+
+func DetectHairpin(portIfName string, log *logrus.Logger) error {
+	link, err := netlink.LinkByName(portIfName)
+	if err != nil {
+		return fmt.Errorf("Unable to find link %q: %s", portIfName, err)
+	}
+
+	ch := make(chan netlink.LinkUpdate)
+	// See EnsureInterface for why done channel is not passed
+	if err := netlink.LinkSubscribe(ch, nil); err != nil {
+		return fmt.Errorf("Unable to subscribe to netlink updates: %s", err)
+	}
+
+	pi, err := netlink.LinkGetProtinfo(link)
+	if err != nil {
+		return fmt.Errorf("Unable to get link protinfo %q: %s", portIfName, err)
+	}
+	if pi.Hairpin {
+		return fmt.Errorf("Hairpin mode enabled on %q", portIfName)
+	}
+
+	go func() {
+		for up := range ch {
+			if up.Attrs().Name == portIfName && up.Attrs().Protinfo != nil &&
+				up.Attrs().Protinfo.Hairpin {
+				log.Errorf("Hairpin mode enabled on %q", portIfName)
+			}
+		}
+	}()
+
+	return nil
+}