Add support for in-container master for ipvlan

Signed-off-by: mmirecki <mmirecki@redhat.com>

plugins/main/ipvlan/ipvlan.go

@@ -36,9 +36,10 @@ import (
 
 type NetConf struct {
 	types.NetConf
-	Master string `json:"master"`
-	Mode   string `json:"mode"`
-	MTU    int    `json:"mtu"`
+	Master     string `json:"master"`
+	Mode       string `json:"mode"`
+	MTU        int    `json:"mtu"`
+	LinkContNs bool   `json:"linkInContainer,omitempty"`
 }
 
 func init() {
@@ -48,9 +49,9 @@ func init() {
 	runtime.LockOSThread()
 }
 
-func loadConf(bytes []byte, cmdCheck bool) (*NetConf, string, error) {
+func loadConf(args *skel.CmdArgs, cmdCheck bool) (*NetConf, string, error) {
 	n := &NetConf{}
-	if err := json.Unmarshal(bytes, n); err != nil {
+	if err := json.Unmarshal(args.StdinData, n); err != nil {
 		return nil, "", fmt.Errorf("failed to load netconf: %v", err)
 	}
 
@@ -73,8 +74,8 @@ func loadConf(bytes []byte, cmdCheck bool) (*NetConf, string, error) {
 	}
 	if n.Master == "" {
 		if result == nil {
-			defaultRouteInterface, err := getDefaultRouteInterfaceName()
-
+			var defaultRouteInterface string
+			defaultRouteInterface, err = getNamespacedDefaultRouteInterfaceName(args.Netns, n.LinkContNs)
 			if err != nil {
 				return nil, "", err
 			}
@@ -124,7 +125,15 @@ func createIpvlan(conf *NetConf, ifName string, netns ns.NetNS) (*current.Interf
 		return nil, err
 	}
 
-	m, err := netlink.LinkByName(conf.Master)
+	var m netlink.Link
+	if conf.LinkContNs {
+		err = netns.Do(func(_ ns.NetNS) error {
+			m, err = netlink.LinkByName(conf.Master)
+			return err
+		})
+	} else {
+		m, err = netlink.LinkByName(conf.Master)
+	}
 	if err != nil {
 		return nil, fmt.Errorf("failed to lookup master %q: %v", conf.Master, err)
 	}
@@ -146,8 +155,14 @@ func createIpvlan(conf *NetConf, ifName string, netns ns.NetNS) (*current.Interf
 		Mode: mode,
 	}
 
-	if err := netlink.LinkAdd(mv); err != nil {
-		return nil, fmt.Errorf("failed to create ipvlan: %v", err)
+	if conf.LinkContNs {
+		err = netns.Do(func(_ ns.NetNS) error {
+			return netlink.LinkAdd(mv)
+		})
+	} else {
+		if err := netlink.LinkAdd(mv); err != nil {
+			return nil, fmt.Errorf("failed to create ipvlan: %v", err)
+		}
 	}
 
 	err = netns.Do(func(_ ns.NetNS) error {
@@ -193,8 +208,31 @@ func getDefaultRouteInterfaceName() (string, error) {
 	return "", fmt.Errorf("no default route interface found")
 }
 
+func getNamespacedDefaultRouteInterfaceName(namespace string, inContainer bool) (string, error) {
+	if !inContainer {
+		return getDefaultRouteInterfaceName()
+	}
+	netns, err := ns.GetNS(namespace)
+	if err != nil {
+		return "", fmt.Errorf("failed to open netns %q: %v", netns, err)
+	}
+	defer netns.Close()
+	var defaultRouteInterface string
+	err = netns.Do(func(_ ns.NetNS) error {
+		defaultRouteInterface, err = getDefaultRouteInterfaceName()
+		if err != nil {
+			return err
+		}
+		return nil
+	})
+	if err != nil {
+		return "", err
+	}
+	return defaultRouteInterface, nil
+}
+
 func cmdAdd(args *skel.CmdArgs) error {
-	n, cniVersion, err := loadConf(args.StdinData, false)
+	n, cniVersion, err := loadConf(args, false)
 	if err != nil {
 		return err
 	}
@@ -272,7 +310,7 @@ func cmdAdd(args *skel.CmdArgs) error {
 }
 
 func cmdDel(args *skel.CmdArgs) error {
-	n, _, err := loadConf(args.StdinData, false)
+	n, _, err := loadConf(args, false)
 	if err != nil {
 		return err
 	}
@@ -320,7 +358,7 @@ func main() {
 
 func cmdCheck(args *skel.CmdArgs) error {
 
-	n, _, err := loadConf(args.StdinData, true)
+	n, _, err := loadConf(args, true)
 	if err != nil {
 		return err
 	}
@@ -369,7 +407,16 @@ func cmdCheck(args *skel.CmdArgs) error {
 			contMap.Sandbox, args.Netns)
 	}
 
-	m, err := netlink.LinkByName(n.Master)
+	var m netlink.Link
+	if n.LinkContNs {
+		err = netns.Do(func(_ ns.NetNS) error {
+			m, err = netlink.LinkByName(n.Master)
+			return err
+		})
+	} else {
+		m, err = netlink.LinkByName(n.Master)
+	}
+
 	if err != nil {
 		return fmt.Errorf("failed to lookup master %q: %v", n.Master, err)
 	}