From 51a7270987557ab12ea735fc9781725d1ce1b0a6 Mon Sep 17 00:00:00 2001
From: jiangpengfei <jiangpengfei9@huawei.com>
Date: Mon, 17 Aug 2020 15:36:32 +0800
Subject: [PATCH 29/50] network: add kata-network del-route subcommand

reason: add kata-network del-route subcommand to delete the
specified route in the Kata VM, del-route is more efficient
than the update-routes subcommand.

Signed-off-by: jiangpengfei <jiangpengfei9@huawei.com>
---
 cli/network.go            |  24 ++++++++++
 virtcontainers/network.go | 115 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 139 insertions(+)

diff --git a/cli/network.go b/cli/network.go
index 2265f54b..046d0ee9 100644
--- a/cli/network.go
+++ b/cli/network.go
@@ -45,6 +45,7 @@ var kataNetworkCLICommand = cli.Command{
 		updateRoutesCommand,
 		listRoutesCommand,
 		addRoutesCommand,
+		deleteRoutesCommand,
 	},
 	Action: func(context *cli.Context) error {
 		return cli.ShowSubcommandHelp(context)
@@ -155,6 +156,29 @@ var addRoutesCommand = cli.Command{
 	},
 }
 
+var deleteRoutesCommand = cli.Command{
+	Name:  "del-route",
+	Usage: "delete one route for a container",
+	ArgsUsage: `del-route <container-id> file or - for stdin
+	file or stdin for example:
+	{
+		"dest":"<[<ip>[/mask] | "default" ]>",
+		"gateway":"[ip]",
+		"device":"[tap-name]",
+	}
+	Only destination is required and others are optional,
+	if device is empty, means search every device`,
+	Flags: []cli.Flag{},
+	Action: func(context *cli.Context) error {
+		ctx, err := cliContextToContext(context)
+		if err != nil {
+			return err
+		}
+
+		return networkModifyCommand(ctx, context.Args().First(), context.Args().Get(1), routeType, vcTypes.NetworkOpRemove)
+	},
+}
+
 var listRoutesCommand = cli.Command{
 	Name:      "list-routes",
 	Usage:     "list network routes in a container",
diff --git a/virtcontainers/network.go b/virtcontainers/network.go
index f3757f84..c7066a11 100644
--- a/virtcontainers/network.go
+++ b/virtcontainers/network.go
@@ -1631,6 +1631,110 @@ func addOneRoute(ns *NetworkNamespace, route *vcTypes.Route) (added *vcTypes.Rou
 	return added, nil
 }
 
+func generateRmRoute(route *vcTypes.Route) (r *netlink.Route, err error) {
+	// destination is required and others are optional
+	if route.Dest == "" {
+		return nil, fmt.Errorf("destination must be specified when remove route.")
+	}
+
+	if route.Device != "" {
+		err = verifyInterfaceName(route.Device)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	r = &netlink.Route{}
+	if route.Dest != "default" {
+		nlIpNet, err := verifyRouteDest(&route.Dest)
+		if err != nil {
+			return nil, err
+		}
+		r.Dst = nlIpNet
+	}
+
+	if route.Gateway != "" {
+		nIP, err := verifyIP(route.Gateway)
+		if err != nil {
+			return nil, err
+		}
+		r.Gw = *nIP
+	}
+
+	if route.Source != "" {
+		nIP, err := verifyIP(route.Source)
+		if err != nil {
+			return nil, err
+		}
+		r.Src = *nIP
+	}
+
+	r.Scope = netlink.Scope(route.Scope)
+
+	return r, nil
+}
+
+// parseToGrpcRoute convert the netlink.Route to vcTypes.Route and deleted route.Dest will
+// be added a prefix "-"
+func parseToGrpcRoute(device string, route *netlink.Route, add bool) (r *vcTypes.Route) {
+	r = &vcTypes.Route{
+		Device: device,
+	}
+	if route.Dst != nil && route.Dst.String() != "<nil>" {
+		r.Dest = route.Dst.String()
+		if add == false {
+			r.Dest = "-" + route.Dst.String()
+		}
+	} else if route.Dst == nil {
+		r.Dest = "default"
+		if add == false {
+			r.Dest = "-default"
+		}
+	}
+	if route.Gw != nil && route.Gw.String() != "<nil>" {
+		r.Gateway = route.Gw.String()
+	}
+
+	return r
+}
+
+func removeRoutes(ns *NetworkNamespace, route *vcTypes.Route) (removed []*vcTypes.Route, err error) {
+	del, err := generateRmRoute(route)
+	if err != nil {
+		return nil, err
+	}
+
+	// remove the lo device related routes
+	if route.Device == localHostDeviceName {
+		removed = append(removed, parseToGrpcRoute(localHostDeviceName, del, false))
+
+		return removed, nil
+	}
+
+	for _, ep := range ns.Endpoints {
+		// if device is empty, means search every device
+		if route.Device != "" && ep.Name() != route.Device {
+			continue
+		}
+
+		netInfo := ep.Properties()
+		for i, exist := range ep.Properties().Routes {
+			if isSameRoute(&exist, del, true) {
+				// need remove
+				netInfo.Routes = append(netInfo.Routes[:i], netInfo.Routes[i+1:]...)
+				ep.SetProperties(netInfo)
+				dev := route.Device
+				if route.Device == "" {
+					dev = netInfo.Iface.Name
+				}
+				removed = append(removed, parseToGrpcRoute(dev, del, false))
+			}
+		}
+	}
+
+	return removed, nil
+}
+
 func updateRoute(ns *NetworkNamespace, route *vcTypes.Route, op vcTypes.NetworkOp) ([]*vcTypes.Route, error) {
 	var updRoutes []*vcTypes.Route
 
@@ -1645,5 +1749,16 @@ func updateRoute(ns *NetworkNamespace, route *vcTypes.Route, op vcTypes.NetworkO
 		updRoutes = append(updRoutes, added)
 	}
 
+	if op == vcTypes.NetworkOpRemove {
+		removed, err := removeRoutes(ns, route)
+		if err != nil {
+			return nil, err
+		}
+		if len(removed) <= 0 {
+			return nil, fmt.Errorf("route of device %s with destination %s is not found", route.Device, route.Dest)
+		}
+		updRoutes = removed
+	}
+
 	return updRoutes, nil
 }
-- 
2.14.3 (Apple Git-98)