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-rw-r--r--tun/tun_darwin.go259
1 files changed, 111 insertions, 148 deletions
diff --git a/tun/tun_darwin.go b/tun/tun_darwin.go
index 6d2e6dd..c9a6c0b 100644
--- a/tun/tun_darwin.go
+++ b/tun/tun_darwin.go
@@ -1,46 +1,46 @@
/* SPDX-License-Identifier: MIT
*
- * Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
*/
package tun
import (
+ "errors"
"fmt"
- "io/ioutil"
+ "io"
"net"
"os"
+ "sync"
"syscall"
+ "time"
"unsafe"
- "golang.org/x/net/ipv6"
"golang.org/x/sys/unix"
)
const utunControlName = "com.apple.net.utun_control"
-// _CTLIOCGINFO value derived from /usr/include/sys/{kern_control,ioccom}.h
-const _CTLIOCGINFO = (0x40000000 | 0x80000000) | ((100 & 0x1fff) << 16) | uint32(byte('N'))<<8 | 3
-
-// sockaddr_ctl specifeid in /usr/include/sys/kern_control.h
-type sockaddrCtl struct {
- scLen uint8
- scFamily uint8
- ssSysaddr uint16
- scID uint32
- scUnit uint32
- scReserved [5]uint32
-}
-
type NativeTun struct {
name string
tunFile *os.File
events chan Event
errors chan error
routeSocket int
+ closeOnce sync.Once
}
-var sockaddrCtlSize uintptr = 32
+func retryInterfaceByIndex(index int) (iface *net.Interface, err error) {
+ for i := 0; i < 20; i++ {
+ iface, err = net.InterfaceByIndex(index)
+ if err != nil && errors.Is(err, unix.ENOMEM) {
+ time.Sleep(time.Duration(i) * time.Second / 3)
+ continue
+ }
+ return iface, err
+ }
+ return nil, err
+}
func (tun *NativeTun) routineRouteListener(tunIfindex int) {
var (
@@ -55,7 +55,7 @@ func (tun *NativeTun) routineRouteListener(tunIfindex int) {
retry:
n, err := unix.Read(tun.routeSocket, data)
if err != nil {
- if errno, ok := err.(syscall.Errno); ok && errno == syscall.EINTR {
+ if errno, ok := err.(unix.Errno); ok && errno == unix.EINTR {
goto retry
}
tun.errors <- err
@@ -74,7 +74,7 @@ func (tun *NativeTun) routineRouteListener(tunIfindex int) {
continue
}
- iface, err := net.InterfaceByIndex(ifindex)
+ iface, err := retryInterfaceByIndex(ifindex)
if err != nil {
tun.errors <- err
return
@@ -107,53 +107,33 @@ func CreateTUN(name string, mtu int) (Device, error) {
}
}
- fd, err := unix.Socket(unix.AF_SYSTEM, unix.SOCK_DGRAM, 2)
-
+ fd, err := socketCloexec(unix.AF_SYSTEM, unix.SOCK_DGRAM, 2)
if err != nil {
return nil, err
}
- var ctlInfo = &struct {
- ctlID uint32
- ctlName [96]byte
- }{}
-
- copy(ctlInfo.ctlName[:], []byte(utunControlName))
-
- _, _, errno := unix.Syscall(
- unix.SYS_IOCTL,
- uintptr(fd),
- uintptr(_CTLIOCGINFO),
- uintptr(unsafe.Pointer(ctlInfo)),
- )
-
- if errno != 0 {
- return nil, fmt.Errorf("_CTLIOCGINFO: %v", errno)
+ ctlInfo := &unix.CtlInfo{}
+ copy(ctlInfo.Name[:], []byte(utunControlName))
+ err = unix.IoctlCtlInfo(fd, ctlInfo)
+ if err != nil {
+ unix.Close(fd)
+ return nil, fmt.Errorf("IoctlGetCtlInfo: %w", err)
}
- sc := sockaddrCtl{
- scLen: uint8(sockaddrCtlSize),
- scFamily: unix.AF_SYSTEM,
- ssSysaddr: 2,
- scID: ctlInfo.ctlID,
- scUnit: uint32(ifIndex) + 1,
+ sc := &unix.SockaddrCtl{
+ ID: ctlInfo.Id,
+ Unit: uint32(ifIndex) + 1,
}
- scPointer := unsafe.Pointer(&sc)
-
- _, _, errno = unix.RawSyscall(
- unix.SYS_CONNECT,
- uintptr(fd),
- uintptr(scPointer),
- uintptr(sockaddrCtlSize),
- )
-
- if errno != 0 {
- return nil, fmt.Errorf("SYS_CONNECT: %v", errno)
+ err = unix.Connect(fd, sc)
+ if err != nil {
+ unix.Close(fd)
+ return nil, err
}
- err = syscall.SetNonblock(fd, true)
+ err = unix.SetNonblock(fd, true)
if err != nil {
+ unix.Close(fd)
return nil, err
}
tun, err := CreateTUNFromFile(os.NewFile(uintptr(fd), ""), mtu)
@@ -161,7 +141,7 @@ func CreateTUN(name string, mtu int) (Device, error) {
if err == nil && name == "utun" {
fname := os.Getenv("WG_TUN_NAME_FILE")
if fname != "" {
- ioutil.WriteFile(fname, []byte(tun.(*NativeTun).name+"\n"), 0400)
+ os.WriteFile(fname, []byte(tun.(*NativeTun).name+"\n"), 0o400)
}
}
@@ -193,7 +173,7 @@ func CreateTUNFromFile(file *os.File, mtu int) (Device, error) {
return nil, err
}
- tun.routeSocket, err = unix.Socket(unix.AF_ROUTE, unix.SOCK_RAW, unix.AF_UNSPEC)
+ tun.routeSocket, err = socketCloexec(unix.AF_ROUTE, unix.SOCK_RAW, unix.AF_UNSPEC)
if err != nil {
tun.tunFile.Close()
return nil, err
@@ -213,27 +193,19 @@ func CreateTUNFromFile(file *os.File, mtu int) (Device, error) {
}
func (tun *NativeTun) Name() (string, error) {
- var ifName struct {
- name [16]byte
- }
- ifNameSize := uintptr(16)
-
- var errno syscall.Errno
+ var err error
tun.operateOnFd(func(fd uintptr) {
- _, _, errno = unix.Syscall6(
- unix.SYS_GETSOCKOPT,
- fd,
+ tun.name, err = unix.GetsockoptString(
+ int(fd),
2, /* #define SYSPROTO_CONTROL 2 */
2, /* #define UTUN_OPT_IFNAME 2 */
- uintptr(unsafe.Pointer(&ifName)),
- uintptr(unsafe.Pointer(&ifNameSize)), 0)
+ )
})
- if errno != 0 {
- return "", fmt.Errorf("SYS_GETSOCKOPT: %v", errno)
+ if err != nil {
+ return "", fmt.Errorf("GetSockoptString: %w", err)
}
- tun.name = string(ifName.name[:ifNameSize-1])
return tun.name, nil
}
@@ -241,61 +213,63 @@ func (tun *NativeTun) File() *os.File {
return tun.tunFile
}
-func (tun *NativeTun) Events() chan Event {
+func (tun *NativeTun) Events() <-chan Event {
return tun.events
}
-func (tun *NativeTun) Read(buff []byte, offset int) (int, error) {
+func (tun *NativeTun) Read(bufs [][]byte, sizes []int, offset int) (int, error) {
+ // TODO: the BSDs look very similar in Read() and Write(). They should be
+ // collapsed, with platform-specific files containing the varying parts of
+ // their implementations.
select {
case err := <-tun.errors:
return 0, err
default:
- buff := buff[offset-4:]
- n, err := tun.tunFile.Read(buff[:])
+ buf := bufs[0][offset-4:]
+ n, err := tun.tunFile.Read(buf[:])
if n < 4 {
return 0, err
}
- return n - 4, err
+ sizes[0] = n - 4
+ return 1, err
}
}
-func (tun *NativeTun) Write(buff []byte, offset int) (int, error) {
-
- // reserve space for header
-
- buff = buff[offset-4:]
-
- // add packet information header
-
- buff[0] = 0x00
- buff[1] = 0x00
- buff[2] = 0x00
-
- if buff[4]>>4 == ipv6.Version {
- buff[3] = unix.AF_INET6
- } else {
- buff[3] = unix.AF_INET
+func (tun *NativeTun) Write(bufs [][]byte, offset int) (int, error) {
+ if offset < 4 {
+ return 0, io.ErrShortBuffer
}
-
- // write
-
- return tun.tunFile.Write(buff)
-}
-
-func (tun *NativeTun) Flush() error {
- // TODO: can flushing be implemented by buffering and using sendmmsg?
- return nil
+ for i, buf := range bufs {
+ buf = buf[offset-4:]
+ buf[0] = 0x00
+ buf[1] = 0x00
+ buf[2] = 0x00
+ switch buf[4] >> 4 {
+ case 4:
+ buf[3] = unix.AF_INET
+ case 6:
+ buf[3] = unix.AF_INET6
+ default:
+ return i, unix.EAFNOSUPPORT
+ }
+ if _, err := tun.tunFile.Write(buf); err != nil {
+ return i, err
+ }
+ }
+ return len(bufs), nil
}
func (tun *NativeTun) Close() error {
- var err2 error
- err1 := tun.tunFile.Close()
- if tun.routeSocket != -1 {
- unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR)
- err2 = unix.Close(tun.routeSocket)
- } else if tun.events != nil {
- close(tun.events)
- }
+ var err1, err2 error
+ tun.closeOnce.Do(func() {
+ err1 = tun.tunFile.Close()
+ if tun.routeSocket != -1 {
+ unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR)
+ err2 = unix.Close(tun.routeSocket)
+ } else if tun.events != nil {
+ close(tun.events)
+ }
+ })
if err1 != nil {
return err1
}
@@ -303,71 +277,60 @@ func (tun *NativeTun) Close() error {
}
func (tun *NativeTun) setMTU(n int) error {
-
- // open datagram socket
-
- var fd int
-
- fd, err := unix.Socket(
+ fd, err := socketCloexec(
unix.AF_INET,
unix.SOCK_DGRAM,
0,
)
-
if err != nil {
return err
}
defer unix.Close(fd)
- // do ioctl call
-
- var ifr [32]byte
- copy(ifr[:], tun.name)
- *(*uint32)(unsafe.Pointer(&ifr[unix.IFNAMSIZ])) = uint32(n)
- _, _, errno := unix.Syscall(
- unix.SYS_IOCTL,
- uintptr(fd),
- uintptr(unix.SIOCSIFMTU),
- uintptr(unsafe.Pointer(&ifr[0])),
- )
-
- if errno != 0 {
- return fmt.Errorf("failed to set MTU on %s", tun.name)
+ var ifr unix.IfreqMTU
+ copy(ifr.Name[:], tun.name)
+ ifr.MTU = int32(n)
+ err = unix.IoctlSetIfreqMTU(fd, &ifr)
+ if err != nil {
+ return fmt.Errorf("failed to set MTU on %s: %w", tun.name, err)
}
return nil
}
func (tun *NativeTun) MTU() (int, error) {
-
- // open datagram socket
-
- fd, err := unix.Socket(
+ fd, err := socketCloexec(
unix.AF_INET,
unix.SOCK_DGRAM,
0,
)
-
if err != nil {
return 0, err
}
defer unix.Close(fd)
- // do ioctl call
-
- var ifr [64]byte
- copy(ifr[:], tun.name)
- _, _, errno := unix.Syscall(
- unix.SYS_IOCTL,
- uintptr(fd),
- uintptr(unix.SIOCGIFMTU),
- uintptr(unsafe.Pointer(&ifr[0])),
- )
- if errno != 0 {
- return 0, fmt.Errorf("failed to get MTU on %s", tun.name)
+ ifr, err := unix.IoctlGetIfreqMTU(fd, tun.name)
+ if err != nil {
+ return 0, fmt.Errorf("failed to get MTU on %s: %w", tun.name, err)
}
- return int(*(*int32)(unsafe.Pointer(&ifr[16]))), nil
+ return int(ifr.MTU), nil
+}
+
+func (tun *NativeTun) BatchSize() int {
+ return 1
+}
+
+func socketCloexec(family, sotype, proto int) (fd int, err error) {
+ // See go/src/net/sys_cloexec.go for background.
+ syscall.ForkLock.RLock()
+ defer syscall.ForkLock.RUnlock()
+
+ fd, err = unix.Socket(family, sotype, proto)
+ if err == nil {
+ unix.CloseOnExec(fd)
+ }
+ return
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.