wireguard-go/tun/wintun/wintun_windows.go
Jason A. Donenfeld 82d2aa87aa wintun: use new swdevice-based API for upcoming Wintun 0.14
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2021-10-12 00:26:46 -06:00

147 lines
4.3 KiB
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2021 WireGuard LLC. All Rights Reserved.
*/
package wintun
import (
"log"
"runtime"
"syscall"
"unsafe"
"golang.org/x/sys/windows"
)
type loggerLevel int
const (
logInfo loggerLevel = iota
logWarn
logErr
)
const AdapterNameMax = 128
type Adapter struct {
handle uintptr
}
var (
modwintun = newLazyDLL("wintun.dll", setupLogger)
procWintunCreateAdapter = modwintun.NewProc("WintunCreateAdapter")
procWintunOpenAdapter = modwintun.NewProc("WintunOpenAdapter")
procWintunCloseAdapter = modwintun.NewProc("WintunCloseAdapter")
procWintunDeleteDriver = modwintun.NewProc("WintunDeleteDriver")
procWintunGetAdapterLUID = modwintun.NewProc("WintunGetAdapterLUID")
procWintunGetRunningDriverVersion = modwintun.NewProc("WintunGetRunningDriverVersion")
)
type TimestampedWriter interface {
WriteWithTimestamp(p []byte, ts int64) (n int, err error)
}
func logMessage(level loggerLevel, timestamp uint64, msg *uint16) int {
if tw, ok := log.Default().Writer().(TimestampedWriter); ok {
tw.WriteWithTimestamp([]byte(log.Default().Prefix()+windows.UTF16PtrToString(msg)), (int64(timestamp)-116444736000000000)*100)
} else {
log.Println(windows.UTF16PtrToString(msg))
}
return 0
}
func setupLogger(dll *lazyDLL) {
var callback uintptr
if runtime.GOARCH == "386" || runtime.GOARCH == "arm" {
callback = windows.NewCallback(func(level loggerLevel, timestampLow, timestampHigh uint32, msg *uint16) int {
return logMessage(level, uint64(timestampHigh)<<32|uint64(timestampLow), msg)
})
} else if runtime.GOARCH == "amd64" || runtime.GOARCH == "arm64" {
callback = windows.NewCallback(logMessage)
}
syscall.Syscall(dll.NewProc("WintunSetLogger").Addr(), 1, callback, 0, 0)
}
func closeAdapter(wintun *Adapter) {
syscall.Syscall(procWintunCloseAdapter.Addr(), 1, wintun.handle, 0, 0)
}
// CreateAdapter creates a Wintun adapter. name is the cosmetic name of the adapter.
// tunnelType represents the type of adapter and should be "Wintun". requestedGUID is
// the GUID of the created network adapter, 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 adapter.
func CreateAdapter(name string, tunnelType string, requestedGUID *windows.GUID) (wintun *Adapter, err error) {
var name16 *uint16
name16, err = windows.UTF16PtrFromString(name)
if err != nil {
return
}
var tunnelType16 *uint16
tunnelType16, err = windows.UTF16PtrFromString(tunnelType)
if err != nil {
return
}
r0, _, e1 := syscall.Syscall(procWintunCreateAdapter.Addr(), 3, uintptr(unsafe.Pointer(name16)), uintptr(unsafe.Pointer(tunnelType16)), uintptr(unsafe.Pointer(requestedGUID)))
if r0 == 0 {
err = e1
return
}
wintun = &Adapter{handle: r0}
runtime.SetFinalizer(wintun, closeAdapter)
return
}
// OpenAdapter opens an existing Wintun adapter by name.
func OpenAdapter(name string) (wintun *Adapter, err error) {
var name16 *uint16
name16, err = windows.UTF16PtrFromString(name)
if err != nil {
return
}
r0, _, e1 := syscall.Syscall(procWintunOpenAdapter.Addr(), 1, uintptr(unsafe.Pointer(name16)), 0, 0)
if r0 == 0 {
err = e1
return
}
wintun = &Adapter{handle: r0}
runtime.SetFinalizer(wintun, closeAdapter)
return
}
// Close closes a Wintun adapter.
func (wintun *Adapter) Close() (err error) {
runtime.SetFinalizer(wintun, nil)
r1, _, e1 := syscall.Syscall(procWintunCloseAdapter.Addr(), 1, wintun.handle, 0, 0)
if r1 == 0 {
err = e1
}
return
}
// Uninstall removes the driver from the system if no drivers are currently in use.
func Uninstall() (err error) {
r1, _, e1 := syscall.Syscall(procWintunDeleteDriver.Addr(), 0, 0, 0, 0)
if r1 == 0 {
err = e1
}
return
}
// RunningVersion returns the version of the running Wintun driver.
func RunningVersion() (version uint32, err error) {
r0, _, e1 := syscall.Syscall(procWintunGetRunningDriverVersion.Addr(), 0, 0, 0, 0)
version = uint32(r0)
if version == 0 {
err = e1
}
return
}
// LUID returns the LUID of the adapter.
func (wintun *Adapter) LUID() (luid uint64) {
syscall.Syscall(procWintunGetAdapterLUID.Addr(), 2, uintptr(wintun.handle), uintptr(unsafe.Pointer(&luid)), 0)
return
}