Add loopback configuration to network setup

cmd/apply.go

@@ -51,7 +51,7 @@ var applyCmd = &cobra.Command{
 				}
 			}
 
-			err := SetupLoopback(netns)
+			err := SetupLoopback(netns, values.Loopback)
 			if err != nil {
 				return err
 			}
@@ -184,13 +184,18 @@ func SetNetns(name string, netns string) error {
 	return ip.SetNetns(name, netns)
 }
 
-func SetupLoopback(netns string) error {
-	return SetLinkUp(ip.IntoNetns(netns), "lo")
+func SetupLoopback(netns string, ethernet config.Ethernet) error {
+	slog.Debug("setup loopback device", "netns", netns, "addresses", ethernet.Addresses, "routes", ethernet.Routes)
+
+	n := ip.IntoNetns(netns)
+	return SetupDevice(n, "lo", ethernet.Addresses, ethernet.Routes)
 }
 
 func SetupEthernets(netns string, ethernets map[string]config.Ethernet) error {
 	n := ip.IntoNetns(netns)
 	for name, values := range ethernets {
+		slog.Debug("setup ethernet device", "netns", netns, "name", name, "addresses", values.Addresses, "routes", values.Routes)
+
 		_, err := n.ShowLink(name)
 		if err == nil {
 			slog.Debug("device is already exists in netns", "name", name, "netns", netns)
@@ -216,6 +221,8 @@ func SetupEthernets(netns string, ethernets map[string]config.Ethernet) error {
 func SetupDummyDevices(netns string, devices map[string]config.Ethernet) error {
 	n := ip.IntoNetns(netns)
 	for name, values := range devices {
+		slog.Debug("setup dummy device", "netns", netns, "name", name, "addresses", values.Addresses, "routes", values.Routes)
+
 		_, err := n.ShowLink(name)
 		if err == nil {
 			slog.Debug("device is already exists in netns", "name", name, "netns", netns)
@@ -245,6 +252,9 @@ func SetupVethDevices(netns string, devices map[string]config.VethDevice) error
 		peerName := values.Peer.Name
 		peerNetns := values.Peer.Netns
 
+		slog.Debug("setup veth device", "netns", netns, "name", name, "addresses", values.Addresses, "routes", values.Routes,
+		"peer name", peerName, "peer netns", peerNetns, "peer addresses", values.Peer.Addresses, "peer routes", values.Peer.Routes)
+
 		// check if device is already exists in netns
 		_, err := n.ShowLink(name)
 		if err == nil {

config/config.go

@@ -34,6 +34,7 @@ type Config struct {
 }
 
 type Netns struct {
+	Loopback     Ethernet              `yaml:"loopback,omitempty"`
 	Ethernets    map[string]Ethernet   `yaml:"ethernets,omitempty"`
 	DummyDevices map[string]Ethernet   `yaml:"dummy-devices,omitempty"`
 	VethDevices  map[string]VethDevice `yaml:"veth-devices,omitempty"`

config/config_test.go

@@ -35,6 +35,13 @@ func TestLoadYamlFiles(t *testing.T) {
 	expected := &Config{
 		Netns: map[string]Netns{
 			"sample1": {
+				Loopback: Ethernet{
+					Addresses: []string{"127.0.0.53/8"},
+					Routes: []Route{{
+						To:  "10.10.0.0/24",
+						Via: "127.0.0.53",
+					}},
+				},
 				Ethernets: map[string]Ethernet{
 					"eth0": {
 						Addresses: []string{

testdata/config/sample1.yaml

@@ -1,5 +1,11 @@
 netns:
   sample1:
+    loopback:
+      addresses:
+        - 127.0.0.53/8
+      routes:
+        - to: 10.10.0.0/24
+          via: 127.0.0.53
     ethernets:
       eth0:
         addresses: