Report Additional POD IPs

Signed-off-by: Lantao Liu <lantaol@google.com>

pkg/server/update_runtime_config.go

@@ -17,8 +17,10 @@ limitations under the License.
 package server
 
 import (
+	"net"
 	"os"
 	"path/filepath"
+	"strings"
 	"text/template"
 
 	"github.com/containerd/containerd/log"
@@ -32,17 +34,36 @@ import (
 type cniConfigTemplate struct {
 	// PodCIDR is the cidr for pods on the node.
 	PodCIDR string
+	// PodCIDRRanges is the cidr ranges for pods on the node.
+	PodCIDRRanges []string
+	// Routes is a list of routes configured.
+	Routes []string
 }
 
-// cniConfigFileName is the name of cni config file generated by containerd.
-const cniConfigFileName = "10-containerd-net.conflist"
+const (
+	// cniConfigFileName is the name of cni config file generated by containerd.
+	cniConfigFileName = "10-containerd-net.conflist"
+	// zeroCIDRv6 is the null route for IPv6.
+	zeroCIDRv6 = "::/0"
+	// zeroCIDRv4 is the null route for IPv4.
+	zeroCIDRv4 = "0.0.0.0/0"
+)
 
 // UpdateRuntimeConfig updates the runtime config. Currently only handles podCIDR updates.
 func (c *criService) UpdateRuntimeConfig(ctx context.Context, r *runtime.UpdateRuntimeConfigRequest) (*runtime.UpdateRuntimeConfigResponse, error) {
-	podCIDR := r.GetRuntimeConfig().GetNetworkConfig().GetPodCidr()
-	if podCIDR == "" {
+	podCIDRs := r.GetRuntimeConfig().GetNetworkConfig().GetPodCidr()
+	if podCIDRs == "" {
 		return &runtime.UpdateRuntimeConfigResponse{}, nil
 	}
+	cidrs := strings.Split(podCIDRs, ",")
+	for i := range cidrs {
+		cidrs[i] = strings.TrimSpace(cidrs[i])
+	}
+	routes, err := getRoutes(cidrs)
+	if err != nil {
+		return nil, errors.Wrap(err, "get routes")
+	}
+
 	confTemplate := c.config.NetworkPluginConfTemplate
 	if confTemplate == "" {
 		log.G(ctx).Info("No cni config template is specified, wait for other system components to drop the config.")
@@ -70,8 +91,38 @@ func (c *criService) UpdateRuntimeConfig(ctx context.Context, r *runtime.UpdateR
 		return nil, errors.Wrapf(err, "failed to open cni config file %q", confFile)
 	}
 	defer f.Close()
-	if err := t.Execute(f, cniConfigTemplate{PodCIDR: podCIDR}); err != nil {
+	if err := t.Execute(f, cniConfigTemplate{
+		PodCIDR:       cidrs[0],
+		PodCIDRRanges: cidrs,
+		Routes:        routes,
+	}); err != nil {
 		return nil, errors.Wrapf(err, "failed to generate cni config file %q", confFile)
 	}
 	return &runtime.UpdateRuntimeConfigResponse{}, nil
 }
+
+// getRoutes generates required routes for the passed in cidrs.
+func getRoutes(cidrs []string) ([]string, error) {
+	var (
+		routes       []string
+		hasV4, hasV6 bool
+	)
+	for _, c := range cidrs {
+		_, cidr, err := net.ParseCIDR(c)
+		if err != nil {
+			return nil, err
+		}
+		if cidr.IP.To4() != nil {
+			hasV4 = true
+		} else {
+			hasV6 = true
+		}
+	}
+	if hasV4 {
+		routes = append(routes, zeroCIDRv4)
+	}
+	if hasV6 {
+		routes = append(routes, zeroCIDRv6)
+	}
+	return routes, nil
+}