wintun: allow controlling GUID

This commit is contained in:
Jason A. Donenfeld 2019-06-09 19:20:17 +02:00
parent bb3f1932fa
commit e924280baa
2 changed files with 29 additions and 2 deletions

View File

@ -60,6 +60,14 @@ func packetAlign(size uint32) uint32 {
// adapter with the same name exist, it is reused.
//
func CreateTUN(ifname string) (TUNDevice, error) {
return CreateTUNWithRequestedGUID(ifname, nil)
}
//
// CreateTUNWithRequestedGUID creates a Wintun adapter with the given name and
// a requested GUID. Should a Wintun adapter with the same name exist, it is reused.
//
func CreateTUNWithRequestedGUID(ifname string, requestedGUID *windows.GUID) (TUNDevice, error) {
var err error
var wt *wintun.Wintun
@ -74,7 +82,7 @@ func CreateTUN(ifname string) (TUNDevice, error) {
} else if err == windows.ERROR_ALREADY_EXISTS {
return nil, fmt.Errorf("Foreign network interface with the same name exists")
}
wt, _, err = wintun.CreateInterface("WireGuard Tunnel Adapter", 0)
wt, _, err = wintun.CreateInterface("WireGuard Tunnel Adapter", requestedGUID, 0)
if err != nil {
return nil, fmt.Errorf("Unable to create Wintun interface: %v", err)
}

View File

@ -176,6 +176,13 @@ func GetInterface(ifname string, hwndParent uintptr) (*Wintun, error) {
// description is a string that supplies the text description of the device.
// description is optional and can be "".
//
// requestedGUID is the GUID of the created network interface, which then
// influences NLA generation deterministically. If it is set to nil, the GUID
// is chosen by the system at random, and hence a new NLA entry is created for
// each new interface. It is called "requested" GUID because the API it uses
// is completely undocumented, and so there could be minor interesting
// complications with its usage.
//
// hwndParent is a handle to the top-level window to use for any user
// interface that is related to non-device-specific actions (such as a select-
// device dialog box that uses the global class driver list). This handle is
@ -184,7 +191,7 @@ func GetInterface(ifname string, hwndParent uintptr) (*Wintun, error) {
//
// Function returns the network interface ID and a flag if reboot is required.
//
func CreateInterface(description string, hwndParent uintptr) (*Wintun, bool, error) {
func CreateInterface(description string, requestedGUID *windows.GUID, hwndParent uintptr) (*Wintun, bool, error) {
// Create an empty device info set for network adapter device class.
devInfoList, err := setupapi.SetupDiCreateDeviceInfoListEx(&deviceClassNetGUID, hwndParent, machineName)
if err != nil {
@ -280,6 +287,18 @@ func CreateInterface(description string, hwndParent uintptr) (*Wintun, bool, err
// Register device co-installers if any. (Ignore errors)
devInfoList.CallClassInstaller(setupapi.DIF_REGISTER_COINSTALLERS, deviceData)
if requestedGUID != nil {
key, err := devInfoList.OpenDevRegKey(deviceData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.SET_VALUE)
if err != nil {
return nil, false, fmt.Errorf("OpenDevRegKey failed: %v", err)
}
err = key.SetStringValue("NetSetupAnticipatedInstanceId", requestedGUID.String())
key.Close()
if err != nil {
return nil, false, fmt.Errorf("SetStringValue(NetSetupAnticipatedInstanceId) failed: %v", err)
}
}
// Install interfaces if any. (Ignore errors)
devInfoList.CallClassInstaller(setupapi.DIF_INSTALLINTERFACES, deviceData)