feat: intercommunication between subclusters

Signed-off-by: wangyizhi1 <[email protected]>

pkg/constants/network.go

@@ -23,5 +23,6 @@ const (
 
 	ALL_ZERO_MAC = "00:00:00:00:00:00"
 
+	IPTablesPreRoutingChain  = "PREROUTING"
 	IPTablesPostRoutingChain = "POSTROUTING"
 )

pkg/network-manager/handlers/globalmap.go

@@ -0,0 +1,62 @@
+package handlers
+
+import (
+	"fmt"
+	"net"
+
+	"k8s.io/klog/v2"
+
+	"github.com/kosmos.io/kosmos/pkg/apis/clusterlink/v1alpha1"
+	"github.com/kosmos.io/kosmos/pkg/constants"
+	"github.com/kosmos.io/kosmos/pkg/network-manager/helpers"
+)
+
+type GlobalMap struct {
+	Next
+}
+
+func (h *GlobalMap) Do(c *Context) (err error) {
+	gwNodes := c.Filter.GetGatewayNodes()
+	epNodes := c.Filter.GetEndpointNodes()
+
+	nodes := append(gwNodes, epNodes...)
+
+	for _, n := range nodes {
+		cluster := c.Filter.GetClusterByName(n.Spec.ClusterName)
+		globalMap := cluster.Spec.GlobalCIDRsMap
+
+		if len(globalMap) > 0 {
+			for src, dst := range cluster.Spec.GlobalCIDRsMap {
+				ipType := helpers.GetIPType(src)
+
+				var vxBridge string
+				if ipType == helpers.IPV6 {
+					vxBridge = constants.VXLAN_BRIDGE_NAME_6
+				} else if ipType == helpers.IPV4 {
+					vxBridge = constants.VXLAN_BRIDGE_NAME
+				}
+
+				// todo in-cluster globalIP access
+				c.Results[n.Name].Iptables = append(c.Results[n.Name].Iptables, v1alpha1.Iptables{
+					Table: "nat",
+					Chain: constants.IPTablesPreRoutingChain,
+					Rule:  fmt.Sprintf("-d %s -i %s -j NETMAP --to %s", dst, vxBridge, src),
+				})
+
+				_, dstIP, err := net.ParseCIDR(dst)
+				if err != nil {
+					klog.Errorf("globalmap: invalid dstIP, err: %v", err)
+					continue
+				}
+
+				c.Results[n.Name].Iptables = append(c.Results[n.Name].Iptables, v1alpha1.Iptables{
+					Table: "nat",
+					Chain: constants.IPTablesPostRoutingChain,
+					Rule:  fmt.Sprintf("-s %s -o %s -j SNAT --to-source %s", src, vxBridge, dstIP.IP),
+				})
+			}
+		}
+	}
+
+	return nil
+}

pkg/network-manager/network_manager.go

@@ -36,7 +36,8 @@ func (n *Manager) CalculateNetworkConfigs(clusters []v1alpha1.Cluster, clusterNo
 		SetNext(&handlers.PodRoutes{}).
 		SetNext(&handlers.VxLocalMacCache{}).
 		SetNext(&handlers.VxBridgeMacCache{}).
-		SetNext(&handlers.HostNetwork{})
+		SetNext(&handlers.HostNetwork{}).
+		SetNext(&handlers.GlobalMap{})
 
 	if err := rootHandler.Run(c); err != nil {
 		return nil, fmt.Errorf("filed to calculate network config, err: %v", err)