package main import ( "fmt" "net" "os" "strconv" "time" envChecks "git.ruekov.eu/ruakij/routingtabletowg/lib/environmentchecks" "git.ruekov.eu/ruakij/routingtabletowg/lib/wgchecks/netchecks" "github.com/vishvananda/netlink" "golang.zx2c4.com/wireguard/wgctrl" "golang.zx2c4.com/wireguard/wgctrl/wgtypes" ) var envRequired = []string{ "INTERFACE", } var envDefaults = map[string]string{ "IPV6_FORMAT": "fc12::%02x%02x:%02x%02x/%d", "FILTER_PREFIX": "100.100", "RECHECK_INTERVAL": "300", } func main() { // Environment-vars err := envChecks.HandleRequired(envRequired) if(err != nil){ logger.Error.Fatal(err) } envChecks.HandleDefaults(envDefaults) // Get the network interface object iface := os.Getenv("INTERFACE") netInterface, err := netlink.LinkByName(iface) if err != nil { logger.Error.Fatal(err) } ipv6Format := os.Getenv("IPV6_FORMAT") ipv6TestStr := *convertIPv4ToIPv6(&ipv6Format, &net.IPNet{IP: net.IPv4(1,1,1,1), Mask: net.CIDRMask(24, net.IPv4len)}) _, err = netlink.ParseIPNet(ipv6TestStr) if err != nil { logger.Error.Fatalf("IPV6_FORMAT is invalid: %s", err) } 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) if err != nil { logger.Error.Fatal(err) } if(len(addrs) == 0){ logger.Error.Fatal("Interface doesnt have IPv4-Adresses") } // Add the IPv6 address to the interface ipv6Str := *convertIPv4ToIPv6(&ipv6Format, addrs[0].IPNet) ipv6, err := netlink.ParseAddr(ipv6Str) 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 { case os.IsExist(err): logger.Warn.Println("Address is already set on interface") default: logger.Error.Fatalf("Failed to set address on interface: %v", err) } } // Create a WireGuard client client, err := wgctrl.New() if err != nil { logger.Error.Fatal(err) } defer client.Close() // Loop indefinitely for { // Get the WireGuard peers on the interface wgDevice, err := client.Device(iface) if err != nil { logger.Error.Fatalf("getting WireGuard device from interface '%s' failed: %s", iface, err) } var wgConfig wgtypes.Config wgConfig.Peers = make([]wgtypes.PeerConfig, 0, len(wgDevice.Peers)) for _, peer := range wgDevice.Peers { // Create slice for 1 expected addition var addAllowedIPs = make([]net.IPNet, 0, 1) // Loop through the allowed-ips and add the ones starting with 100.100 for _, allowedIP := range peer.AllowedIPs { if allowedIP.String()[:len(filterPrefix)] == filterPrefix { // Convert the IPv4 allowed-ip to an IPv6 address 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) continue } // Check if already set if i, _ := netchecks.IPNetIndexByIPNet(&peer.AllowedIPs, ipv6); i != -1 { continue } // Add the IPv6 allowed-ip to the peer addAllowedIPs = append(addAllowedIPs, *ipv6) } } if(len(addAllowedIPs) > 0){ // Create peer-config peerConfig := wgtypes.PeerConfig{ PublicKey: peer.PublicKey, AllowedIPs: append(peer.AllowedIPs, addAllowedIPs...), } // Add entry wgConfig.Peers = append(wgConfig.Peers, peerConfig) } } if(len(wgConfig.Peers) == 0){ logger.Info.Println("No changes, skipping") } else { err = client.ConfigureDevice(iface, wgConfig) if(err != nil){ logger.Error.Fatalf("Error configuring wg-device '%s': %s", iface, err) } } // 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[3], net.IPv6len*8-(net.IPv4len*8-CIDR)) return &ipv6Str }