flannel: set up route for the entire flannel network

Without it, packets leave via default route iface
and come back via interface added by flannel plugin.
If rp_filter=1, the packets are dropped.

diff --git a/plugins/meta/flannel/flannel.go b/plugins/meta/flannel/flannel.go
index 458df8f..059b2bb 100644 (file)
--- a/plugins/meta/flannel/flannel.go
+++ b/plugins/meta/flannel/flannel.go
@@ -45,6 +45,7 @@ type NetConf struct {
 }
 
 type subnetEnv struct {
+       nw     *net.IPNet
        sn     *net.IPNet
        mtu    uint
        ipmasq bool
@@ -73,6 +74,12 @@ func loadFlannelSubnetEnv(fn string) (*subnetEnv, error) {
        for s.Scan() {
                parts := strings.SplitN(s.Text(), "=", 2)
                switch parts[0] {
+               case "FLANNEL_NETWORK":
+                       _, se.nw, err = net.ParseCIDR(parts[1])
+                       if err != nil {
+                               return nil, err
+                       }
+
                case "FLANNEL_SUBNET":
                        _, se.sn, err = net.ParseCIDR(parts[1])
                        if err != nil {
@@ -189,9 +196,14 @@ func cmdAdd(args *skel.CmdArgs) error {
                }
        }
 
-       n.Delegate["ipam"] = map[string]string{
+       n.Delegate["ipam"] = map[string]interface{}{
                "type":   "host-local",
                "subnet": fenv.sn.String(),
+               "routes": []plugin.Route{
+                       plugin.Route{
+                               Dst: *fenv.nw,
+                       },
+               },
        }
 
        return delegateAdd(args.ContainerID, n.Delegate)