98 lines
2 KiB
Go
98 lines
2 KiB
Go
|
/* SPDX-License-Identifier: MIT
|
||
|
|
*
|
||
|
|
* Copyright (C) 2020 WireGuard LLC. All Rights Reserved.
|
||
|
|
*/
|
||
|
|
|
||
|
|
package wintun
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"sync"
|
||
|
|
"sync/atomic"
|
||
|
|
"unsafe"
|
||
|
|
|
||
|
|
"golang.org/x/sys/windows"
|
||
|
|
"golang.zx2c4.com/wireguard/tun/wintun/memmod"
|
||
|
|
"golang.zx2c4.com/wireguard/tun/wintun/resource"
|
||
|
|
)
|
||
|
|
|
||
|
|
type lazyDLL struct {
|
||
|
|
Name string
|
||
|
|
mu sync.Mutex
|
||
|
|
module *memmod.Module
|
||
|
|
}
|
||
|
|
|
||
|
|
func newLazyDLL(name string) *lazyDLL {
|
||
|
|
return &lazyDLL{Name: name}
|
||
|
|
}
|
||
|
|
|
||
|
|
func (d *lazyDLL) Load() error {
|
||
|
|
if atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&d.module))) != nil {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
d.mu.Lock()
|
||
|
|
defer d.mu.Unlock()
|
||
|
|
if d.module != nil {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
const ourModule windows.Handle = 0
|
||
|
|
resInfo, err := resource.FindByName(ourModule, d.Name, resource.RT_RCDATA)
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("Unable to find \"%v\" RCDATA resource: %v", d.Name, err)
|
||
|
|
}
|
||
|
|
data, err := resource.Load(ourModule, resInfo)
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("Unable to load resource: %v", err)
|
||
|
|
}
|
||
|
|
module, err := memmod.LoadLibrary(data)
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("Unable to load library: %v", err)
|
||
|
|
}
|
||
|
|
|
||
|
|
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&d.module)), unsafe.Pointer(module))
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func (d *lazyDLL) NewProc(name string) *lazyProc {
|
||
|
|
return &lazyProc{dll: d, Name: name}
|
||
|
|
}
|
||
|
|
|
||
|
|
type lazyProc struct {
|
||
|
|
Name string
|
||
|
|
mu sync.Mutex
|
||
|
|
dll *lazyDLL
|
||
|
|
addr uintptr
|
||
|
|
}
|
||
|
|
|
||
|
|
func (p *lazyProc) Find() error {
|
||
|
|
if atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&p.addr))) != nil {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
p.mu.Lock()
|
||
|
|
defer p.mu.Unlock()
|
||
|
|
if p.addr != 0 {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
err := p.dll.Load()
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("Error loading %v DLL: %v", p.dll.Name, err)
|
||
|
|
}
|
||
|
|
addr, err := p.dll.module.ProcAddressByName(p.Name)
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("Error getting %v address: %v", p.Name, err)
|
||
|
|
}
|
||
|
|
|
||
|
|
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&p.addr)), unsafe.Pointer(addr))
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func (p *lazyProc) Addr() uintptr {
|
||
|
|
err := p.Find()
|
||
|
|
if err != nil {
|
||
|
|
panic(err)
|
||
|
|
}
|
||
|
|
return p.addr
|
||
|
|
}
|