Use uint64 for MTU for forward-compatibility

src/admin/admin.go

@@ -250,7 +250,6 @@ func (a *AdminSocket) handleRequest(conn net.Conn) {
 				}
 			}
 		}
-		j, _ := json.Marshal(resp)
 		if err = encoder.Encode(resp); err != nil {
 			a.log.Debugln("Encode error:", err)
 		}

src/config/config.go

@@ -69,7 +69,7 @@ type NodeConfig struct {
 	PrivateKey          string                 `comment:"Your private signing key. DO NOT share this with anyone!"`
 	LinkLocalTCPPort    uint16                 `comment:"The port number to be used for the link-local TCP listeners for the\nconfigured MulticastInterfaces. This option does not affect listeners\nspecified in the Listen option. Unless you plan to firewall link-local\ntraffic, it is best to leave this as the default value of 0. This\noption cannot currently be changed by reloading config during runtime."`
 	IfName              string                 `comment:"Local network interface name for TUN adapter, or \"auto\" to select\nan interface automatically, or \"none\" to run without TUN."`
-	IfMTU               uint16                 `comment:"Maximum Transmission Unit (MTU) size for your local TUN interface.\nDefault is the largest supported size for your platform. The lowest\npossible value is 1280."`
+	IfMTU               uint64                 `comment:"Maximum Transmission Unit (MTU) size for your local TUN interface.\nDefault is the largest supported size for your platform. The lowest\npossible value is 1280."`
 	SessionFirewall     SessionFirewall        `comment:"The session firewall controls who can send/receive network traffic\nto/from. This is useful if you want to protect this node without\nresorting to using a real firewall. This does not affect traffic\nbeing routed via this node to somewhere else. Rules are prioritised as\nfollows: blacklist, whitelist, always allow outgoing, direct, remote."`
 	NodeInfoPrivacy     bool                   `comment:"By default, nodeinfo contains some defaults including the platform,\narchitecture and Yggdrasil version. These can help when surveying\nthe network and diagnosing network routing problems. Enabling\nnodeinfo privacy prevents this, so that only items specified in\n\"NodeInfo\" are sent back if specified."`
 	NodeInfo            map[string]interface{} `comment:"Optional node info. This must be a { \"key\": \"value\", ... } map\nor set as null. This is entirely optional but, if set, is visible\nto the whole network on request."`

src/defaults/defaults.go

@@ -14,7 +14,7 @@ type platformDefaultParameters struct {
 	DefaultMulticastInterfaces []string
 
 	// TUN/TAP
-	MaximumIfMTU  uint16
-	DefaultIfMTU  uint16
+	MaximumIfMTU  uint64
+	DefaultIfMTU  uint64
 	DefaultIfName string
 }

src/tuntap/admin.go

@@ -7,7 +7,7 @@ import (
 )
 
 type GetTUNRequest struct{}
-type GetTUNResponse map[string]uint16
+type GetTUNResponse map[string]uint64
 
 func (t *TunAdapter) getTUNHandler(req *GetTUNRequest, res *GetTUNResponse) error {
 	res = &GetTUNResponse{

src/tuntap/tun.go

@@ -39,7 +39,7 @@ type TunAdapter struct {
 	log         *log.Logger
 	addr        address.Address
 	subnet      address.Subnet
-	mtu         uint16
+	mtu         uint64
 	iface       tun.Device
 	phony.Inbox // Currently only used for _handlePacket from the reader, TODO: all the stuff that currently needs a mutex below
 	//mutex        sync.RWMutex // Protects the below
@@ -55,7 +55,7 @@ func (tun *TunAdapter) SetSessionGatekeeper(gatekeeper func(pubkey ed25519.Publi
 
 // Gets the maximum supported MTU for the platform based on the defaults in
 // defaults.GetDefaults().
-func getSupportedMTU(mtu uint16) uint16 {
+func getSupportedMTU(mtu uint64) uint64 {
 	if mtu < 1280 {
 		return 1280
 	}
@@ -77,7 +77,7 @@ func (tun *TunAdapter) Name() string {
 // MTU gets the adapter's MTU. This can range between 1280 and 65535, although
 // the maximum value is determined by your platform. The returned value will
 // never exceed that of MaximumMTU().
-func (tun *TunAdapter) MTU() uint16 {
+func (tun *TunAdapter) MTU() uint64 {
 	return getSupportedMTU(tun.mtu)
 }
 
@@ -88,14 +88,14 @@ func DefaultName() string {
 
 // DefaultMTU gets the default TUN interface MTU for your platform. This can
 // be as high as MaximumMTU(), depending on platform, but is never lower than 1280.
-func DefaultMTU() uint16 {
+func DefaultMTU() uint64 {
 	return defaults.GetDefaults().DefaultIfMTU
 }
 
 // MaximumMTU returns the maximum supported TUN interface MTU for your
 // platform. This can be as high as 65535, depending on platform, but is never
 // lower than 1280.
-func MaximumMTU() uint16 {
+func MaximumMTU() uint64 {
 	return defaults.GetDefaults().MaximumIfMTU
 }
 
@@ -150,7 +150,7 @@ func (tun *TunAdapter) _start() error {
 	}
 	mtu := current.IfMTU
 	if tun.core.MTU() < uint64(mtu) {
-		mtu = uint16(tun.core.MTU())
+		mtu = tun.core.MTU()
 	}
 	if err := tun.setup(current.IfName, addr, mtu); err != nil {
 		return err

src/tuntap/tun_bsd.go

@@ -73,14 +73,14 @@ type in6_ifreq_lifetime struct {
 }
 
 // Configures the TUN adapter with the correct IPv6 address and MTU.
-func (tun *TunAdapter) setup(ifname string, addr string, mtu MTU) error {
+func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
 	iface, err := wgtun.CreateTUN(ifname, int(mtu))
 	if err != nil {
 		panic(err)
 	}
 	tun.iface = iface
 	if mtu, err := iface.MTU(); err == nil {
-		tun.mtu = getSupportedMTU(MTU(mtu))
+		tun.mtu = getSupportedMTU(uint64(mtu))
 	} else {
 		tun.mtu = 0
 	}

src/tuntap/tun_darwin.go

@@ -16,7 +16,7 @@ import (
 )
 
 // Configures the "utun" adapter with the correct IPv6 address and MTU.
-func (tun *TunAdapter) setup(ifname string, addr string, mtu uint16) error {
+func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
 	if ifname == "auto" {
 		ifname = "utun"
 	}
@@ -26,7 +26,7 @@ func (tun *TunAdapter) setup(ifname string, addr string, mtu uint16) error {
 	}
 	tun.iface = iface
 	if m, err := iface.MTU(); err == nil {
-		tun.mtu = getSupportedMTU(uint16(m))
+		tun.mtu = getSupportedMTU(uint64(m))
 	} else {
 		tun.mtu = 0
 	}

src/tuntap/tun_linux.go

@@ -10,7 +10,7 @@ import (
 )
 
 // Configures the TUN adapter with the correct IPv6 address and MTU.
-func (tun *TunAdapter) setup(ifname string, addr string, mtu MTU) error {
+func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
 	if ifname == "auto" {
 		ifname = "\000"
 	}
@@ -20,7 +20,7 @@ func (tun *TunAdapter) setup(ifname string, addr string, mtu MTU) error {
 	}
 	tun.iface = iface
 	if mtu, err := iface.MTU(); err == nil {
-		tun.mtu = getSupportedMTU(MTU(mtu))
+		tun.mtu = getSupportedMTU(uint64(mtu))
 	} else {
 		tun.mtu = 0
 	}

src/tuntap/tun_other.go

@@ -10,14 +10,14 @@ import (
 )
 
 // Configures the TUN adapter with the correct IPv6 address and MTU.
-func (tun *TunAdapter) setup(ifname string, addr string, mtu int) error {
+func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
 	iface, err := wgtun.CreateTUN(ifname, mtu)
 	if err != nil {
 		panic(err)
 	}
 	tun.iface = iface
 	if mtu, err := iface.MTU(); err == nil {
-		tun.mtu = getSupportedMTU(mtu)
+		tun.mtu = getSupportedMTU(uint64(mtu))
 	} else {
 		tun.mtu = 0
 	}

src/tuntap/tun_windows.go

@@ -19,7 +19,7 @@ import (
 // This is to catch Windows platforms
 
 // Configures the TUN adapter with the correct IPv6 address and MTU.
-func (tun *TunAdapter) setup(ifname string, addr string, mtu MTU) error {
+func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
 	if ifname == "auto" {
 		ifname = defaults.GetDefaults().DefaultIfName
 	}
@@ -43,14 +43,14 @@ func (tun *TunAdapter) setup(ifname string, addr string, mtu MTU) error {
 			return err
 		}
 		if mtu, err := iface.MTU(); err == nil {
-			tun.mtu = MTU(mtu)
+			tun.mtu = uint64(mtu)
 		}
 		return nil
 	})
 }
 
 // Sets the MTU of the TAP adapter.
-func (tun *TunAdapter) setupMTU(mtu MTU) error {
+func (tun *TunAdapter) setupMTU(mtu uint64) error {
 	if tun.iface == nil || tun.Name() == "" {
 		return errors.New("Can't configure MTU as TUN adapter is not present")
 	}