Update systemd-example

README.md

@@ -71,16 +71,17 @@ Or using a systemd-service based on the example:
 [Unit]
 Description=WireGuard IPv6 converter for netbird
 BindsTo=netbird.service
+After=netbird.service
 
 [Service]
 Type=simple
+ExecStartPre=/bin/sleep 10
 ExecStart=/usr/local/bin/wg-ipv6-converter
 Restart=always
-RestartSec=60
-StandardOutput=syslog
-StandardError=syslog
+RestartSec=30
 
 Environment="INTERFACE=wt0"
+Environment="RECHECK_INTERVAL=60"
 
 [Install]
 WantedBy=multi-user.target

cmd/app/main.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net"
 	"os"
+	"strconv"
 	"time"
 
 	envChecks "git.ruekov.eu/ruakij/routingtabletowg/lib/environmentchecks"
@@ -18,8 +19,9 @@ var envRequired = []string{
 	"INTERFACE",
 }
 var envDefaults = map[string]string{
-    "IPV6_FORMAT": "fc12::%02x%02x:%02x%02x/%s",
+    "IPV6_FORMAT": "fc12::%02x%02x:%02x%02x/%d",
     "FILTER_PREFIX": "100.100",
+    "RECHECK_INTERVAL": "300",
 }
 
 func main() {
@@ -46,6 +48,12 @@ func main() {
 
     filterPrefix := os.Getenv("FILTER_PREFIX")
 
+    checkIntervalStr := os.Getenv("RECHECK_INTERVAL")
+    checkIntervalSec, err := strconv.Atoi(checkIntervalStr)
+	if err != nil {
+		logger.Error.Fatalf("Couldn't read RECHECK_INTERVAL '%s': %s", checkIntervalStr, err)
+	}
+    checkInterval := time.Second * time.Duration(checkIntervalSec)
 
     // Get the IPv4 address of the interface
     addrs, err := netlink.AddrList(netInterface, netlink.FAMILY_V4)
@@ -62,6 +70,7 @@ func main() {
     if err != nil {
         logger.Error.Fatal(err)
     }
+    logger.Info.Printf("Adding converted %s -> %s to interface", addrs[0].IPNet.String(), ipv6Str)
     err = netlink.AddrAdd(netInterface, ipv6)
     if err != nil {
         switch {
@@ -98,7 +107,8 @@ func main() {
             for _, allowedIP := range peer.AllowedIPs {
                 if allowedIP.String()[:len(filterPrefix)] == filterPrefix {
                     // Convert the IPv4 allowed-ip to an IPv6 address
-                    ipv6Str := *convertIPv4ToIPv6(&ipv6Format, &net.IPNet{IP: allowedIP.IP, Mask: allowedIP.Mask})
+                    ipv6Str := *convertIPv4ToIPv6(&ipv6Format, &allowedIP)
+                    logger.Info.Printf("AllowedIP %s -> %s to peer %s", allowedIP.String(), ipv6Str, peer.PublicKey)
                     ipv6, err := netlink.ParseIPNet(ipv6Str)
                     if err != nil {
                         logger.Warn.Printf("Couldnt parse IPv6 address %s of peer %s: %s", ipv6Str, peer.PublicKey, err)
@@ -136,14 +146,14 @@ func main() {
             }
         }
         
-        // Sleep for 300 seconds before running the loop again
-        time.Sleep(time.Second * 300)
+        // Sleep for x seconds before running the loop again
+        time.Sleep(checkInterval)
     }
 }
 
 func convertIPv4ToIPv6(ipv6Format *string, ipv4 *net.IPNet) (*string) {
     CIDR, _ := ipv4.Mask.Size()
     // Run format
-    ipv6Str := fmt.Sprintf(*ipv6Format, (*ipv4).IP[0], (*ipv4).IP[1], (*ipv4).IP[2], (*ipv4).IP[4], 128-CIDR)
+    ipv6Str := fmt.Sprintf(*ipv6Format, (*ipv4).IP[0], (*ipv4).IP[1], (*ipv4).IP[2], (*ipv4).IP[3], net.IPv6len*8-(net.IPv4len*8-CIDR))
     return &ipv6Str
 }