f-15: ia: first subnet try

Signed-off-by: GnomeZworc <nicolas.boufidjeline@g3e.fr>

internal/subnet/delete.go

@@ -0,0 +1,95 @@
+package subnet
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+
+	"git.g3e.fr/syonad/two/internal/netif"
+	"git.g3e.fr/syonad/two/internal/netns"
+	"git.g3e.fr/syonad/two/pkg/db/kv"
+	"git.g3e.fr/syonad/two/pkg/systemd"
+
+	"github.com/dgraph-io/badger/v4"
+)
+
+func DeleteSubnet(db *badger.DB, subnetName string) error {
+	state, err := kv.GetFromDB(db, "subnet/"+subnetName+"/state")
+	if err != nil {
+		return err
+	}
+	if state != "deleting" {
+		return nil
+	}
+
+	vpcName, err := kv.GetFromDB(db, "subnet/"+subnetName+"/vpc")
+	if err != nil {
+		return fmt.Errorf("get vpc: %w", err)
+	}
+
+	vxlanIDStr, err := kv.GetFromDB(db, "subnet/"+subnetName+"/vxlan_id")
+	if err != nil {
+		return fmt.Errorf("get vxlan_id: %w", err)
+	}
+
+	subnetID := strings.SplitN(subnetName, "-", 2)[1]
+	bridge := "br-" + subnetID
+	vxlanIface := "vxlan-" + vxlanIDStr
+
+	// arrêt du service dnsmasq
+	svc, err := systemd.New()
+	if err != nil {
+		return fmt.Errorf("connect to systemd: %w", err)
+	}
+	defer svc.Close()
+
+	svcName := "dnsmasq@" + vpcName + "_" + bridge + ".service"
+	if err := svc.Stop(svcName); err != nil {
+		return fmt.Errorf("stop dnsmasq: %w", err)
+	}
+
+	// suppression de la config dnsmasq
+	if err := os.Remove("/etc/dnsmasq.d/" + vpcName + "_" + bridge + ".conf"); err != nil && !os.IsNotExist(err) {
+		return fmt.Errorf("remove dnsmasq config: %w", err)
+	}
+
+	// suppression des règles ebtables
+	exec.Command("ebtables", "-D", "FORWARD",
+		"--out-interface", bridge,
+		"-p", "arp",
+		"--arp-op", "Request",
+		"-j", "DROP").Run()
+
+	exec.Command("ebtables", "-D", "FORWARD",
+		"--out-interface", bridge,
+		"-p", "IPv4",
+		"--ip-protocol", "udp",
+		"--ip-source-port", "67:68",
+		"--ip-destination-port", "67:68",
+		"-j", "DROP").Run()
+
+	// suppression du bridge dans le netns VPC
+	if err := netns.Call(vpcName, func() error {
+		return netif.DeleteLink(bridge)
+	}); err != nil {
+		return fmt.Errorf("delete bridge in netns: %w", err)
+	}
+
+	// suppression du vxlan
+	if err := netif.DeleteLink(vxlanIface); err != nil {
+		return fmt.Errorf("delete vxlan: %w", err)
+	}
+
+	// suppression du veth pair (supprime les deux côtés)
+	if err := netif.DeleteLink("v-" + subnetID + "-e"); err != nil {
+		return fmt.Errorf("delete veth: %w", err)
+	}
+
+	// suppression du bridge dans le root netns
+	if err := netif.DeleteLink(bridge); err != nil {
+		return fmt.Errorf("delete bridge: %w", err)
+	}
+
+	return kv.AddInDB(db, "subnet/"+subnetName+"/state", "deleted")
+}