xsteadfastx/wireguard-go
1
0
Fork 0
mirror of https://git.zx2c4.com/wireguard-go synced 2024-11-14 16:55:15 +01:00
Code Issues Releases Wiki Activity

conn, device, tun: implement vectorized I/O plumbing

Browse Source 
Accept packet vectors for reading and writing in the tun.Device and
conn.Bind interfaces, so that the internal plumbing between these
interfaces now passes a vector of packets. Vectors move untouched
between these interfaces, i.e. if 128 packets are received from
conn.Bind.Read(), 128 packets are passed to tun.Device.Write(). There is
no internal buffering.

Currently, existing implementations are only adjusted to have vectors
of length one. Subsequent patches will improve that.

Also, as a related fixup, use the unix and windows packages rather than
the syscall package when possible.

Co-authored-by: James Tucker <james@tailscale.com>
Signed-off-by: James Tucker <james@tailscale.com>
Signed-off-by: Jordan Whited <jordan@tailscale.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This commit is contained in:
Jordan Whited 2023-03-02 14:48:02 -08:00 committed by Jason A. Donenfeld
parent 21636207a6
commit 3bb8fec7e4
25 changed files with 1046 additions and 514 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
conn/bind_linux.go
View File

@ -193,6 +193,10 @@ func (bind *LinuxSocketBind) SetMark(value uint32) error {
return nil
}
func (bind *LinuxSocketBind) BatchSize() int {
return 1
}
func (bind *LinuxSocketBind) Close() error {
// Take a readlock to shut down the sockets...
bind.mu.RLock()
@ -223,29 +227,39 @@ func (bind *LinuxSocketBind) Close() error {
return err2
}
func (bind *LinuxSocketBind) receiveIPv4(buf []byte) (int, Endpoint, error) {
func (bind *LinuxSocketBind) receiveIPv4(buffs [][]byte, sizes []int, eps []Endpoint) (int, error) {
bind.mu.RLock()
defer bind.mu.RUnlock()
if bind.sock4 == -1 {
return 0, nil, net.ErrClosed
return 0, net.ErrClosed
}
var end LinuxSocketEndpoint
n, err := receive4(bind.sock4, buf, &end)
return n, &end, err
n, err := receive4(bind.sock4, buffs[0], &end)
if err != nil {
return 0, err
}
eps[0] = &end
sizes[0] = n
return 1, nil
}
func (bind *LinuxSocketBind) receiveIPv6(buf []byte) (int, Endpoint, error) {
func (bind *LinuxSocketBind) receiveIPv6(buffs [][]byte, sizes []int, eps []Endpoint) (int, error) {
bind.mu.RLock()
defer bind.mu.RUnlock()
if bind.sock6 == -1 {
return 0, nil, net.ErrClosed
return 0, net.ErrClosed
}
var end LinuxSocketEndpoint
n, err := receive6(bind.sock6, buf, &end)
return n, &end, err
n, err := receive6(bind.sock6, buffs[0], &end)
if err != nil {
return 0, err
}
eps[0] = &end
sizes[0] = n
return 1, nil
}
func (bind *LinuxSocketBind) Send(buff []byte, end Endpoint) error {
func (bind *LinuxSocketBind) Send(buffs [][]byte, end Endpoint) error {
nend, ok := end.(*LinuxSocketEndpoint)
if !ok {
return ErrWrongEndpointType
@ -256,13 +270,24 @@ func (bind *LinuxSocketBind) Send(buff []byte, end Endpoint) error {
if bind.sock4 == -1 {
return net.ErrClosed
}
return send4(bind.sock4, nend, buff)
for _, buff := range buffs {
err := send4(bind.sock4, nend, buff)
if err != nil {
return err
}
}
} else {
if bind.sock6 == -1 {
return net.ErrClosed
}
return send6(bind.sock6, nend, buff)
for _, buff := range buffs {
err := send6(bind.sock6, nend, buff)
if err != nil {
return err
}
}
}
return nil
}
func (end *LinuxSocketEndpoint) SrcIP() netip.Addr {

37
conn/bind_std.go
View File

@ -128,6 +128,10 @@ again:
return fns, uint16(port), nil
}
func (bind *StdNetBind) BatchSize() int {
return 1
}
func (bind *StdNetBind) Close() error {
bind.mu.Lock()
defer bind.mu.Unlock()
@ -150,20 +154,30 @@ func (bind *StdNetBind) Close() error {
}
func (*StdNetBind) makeReceiveIPv4(conn *net.UDPConn) ReceiveFunc {
return func(buff []byte) (int, Endpoint, error) {
n, endpoint, err := conn.ReadFromUDPAddrPort(buff)
return n, asEndpoint(endpoint), err
return func(buffs [][]byte, sizes []int, eps []Endpoint) (n int, err error) {
size, endpoint, err := conn.ReadFromUDPAddrPort(buffs[0])
if err == nil {
sizes[0] = size
eps[0] = asEndpoint(endpoint)
return 1, nil
}
return 0, err
}
}
func (*StdNetBind) makeReceiveIPv6(conn *net.UDPConn) ReceiveFunc {
return func(buff []byte) (int, Endpoint, error) {
n, endpoint, err := conn.ReadFromUDPAddrPort(buff)
return n, asEndpoint(endpoint), err
return func(buffs [][]byte, sizes []int, eps []Endpoint) (n int, err error) {
size, endpoint, err := conn.ReadFromUDPAddrPort(buffs[0])
if err == nil {
sizes[0] = size
eps[0] = asEndpoint(endpoint)
return 1, nil
}
return 0, err
}
}
func (bind *StdNetBind) Send(buff []byte, endpoint Endpoint) error {
func (bind *StdNetBind) Send(buffs [][]byte, endpoint Endpoint) error {
var err error
nend, ok := endpoint.(StdNetEndpoint)
if !ok {
@ -186,8 +200,13 @@ func (bind *StdNetBind) Send(buff []byte, endpoint Endpoint) error {
if conn == nil {
return syscall.EAFNOSUPPORT
}
_, err = conn.WriteToUDPAddrPort(buff, addrPort)
return err
for _, buff := range buffs {
_, err = conn.WriteToUDPAddrPort(buff, addrPort)
if err != nil {
return err
}
}
return nil
}
// endpointPool contains a re-usable set of mapping from netip.AddrPort to Endpoint.

67
conn/bind_windows.go
View File

@ -321,6 +321,11 @@ func (bind *WinRingBind) Close() error {
return nil
}
func (bind *WinRingBind) BatchSize() int {
// TODO: implement batching in and out of the ring
return 1
}
func (bind *WinRingBind) SetMark(mark uint32) error {
return nil
}
@ -409,16 +414,22 @@ retry:
return n, &ep, nil
}
func (bind *WinRingBind) receiveIPv4(buf []byte) (int, Endpoint, error) {
func (bind *WinRingBind) receiveIPv4(buffs [][]byte, sizes []int, eps []Endpoint) (int, error) {
bind.mu.RLock()
defer bind.mu.RUnlock()
return bind.v4.Receive(buf, &bind.isOpen)
n, ep, err := bind.v4.Receive(buffs[0], &bind.isOpen)
sizes[0] = n
eps[0] = ep
return 1, err
}
func (bind *WinRingBind) receiveIPv6(buf []byte) (int, Endpoint, error) {
func (bind *WinRingBind) receiveIPv6(buffs [][]byte, sizes []int, eps []Endpoint) (int, error) {
bind.mu.RLock()
defer bind.mu.RUnlock()
return bind.v6.Receive(buf, &bind.isOpen)
n, ep, err := bind.v6.Receive(buffs[0], &bind.isOpen)
sizes[0] = n
eps[0] = ep
return 1, err
}
func (bind *afWinRingBind) Send(buf []byte, nend *WinRingEndpoint, isOpen *atomic.Uint32) error {
@ -473,32 +484,38 @@ func (bind *afWinRingBind) Send(buf []byte, nend *WinRingEndpoint, isOpen *atomi
return winrio.SendEx(bind.rq, dataBuffer, 1, nil, addressBuffer, nil, nil, 0, 0)
}
func (bind *WinRingBind) Send(buf []byte, endpoint Endpoint) error {
func (bind *WinRingBind) Send(buffs [][]byte, endpoint Endpoint) error {
nend, ok := endpoint.(*WinRingEndpoint)
if !ok {
return ErrWrongEndpointType
}
bind.mu.RLock()
defer bind.mu.RUnlock()
switch nend.family {
case windows.AF_INET:
if bind.v4.blackhole {
return nil
for _, buf := range buffs {
switch nend.family {
case windows.AF_INET:
if bind.v4.blackhole {
continue
}
if err := bind.v4.Send(buf, nend, &bind.isOpen); err != nil {
return err
}
case windows.AF_INET6:
if bind.v6.blackhole {
continue
}
if err := bind.v6.Send(buf, nend, &bind.isOpen); err != nil {
return err
}
}
return bind.v4.Send(buf, nend, &bind.isOpen)
case windows.AF_INET6:
if bind.v6.blackhole {
return nil
}
return bind.v6.Send(buf, nend, &bind.isOpen)
}
return nil
}
func (bind *StdNetBind) BindSocketToInterface4(interfaceIndex uint32, blackhole bool) error {
bind.mu.Lock()
defer bind.mu.Unlock()
sysconn, err := bind.ipv4.SyscallConn()
func (s *StdNetBind) BindSocketToInterface4(interfaceIndex uint32, blackhole bool) error {
s.mu.Lock()
defer s.mu.Unlock()
sysconn, err := s.ipv4.SyscallConn()
if err != nil {
return err
}
@ -511,14 +528,14 @@ func (bind *StdNetBind) BindSocketToInterface4(interfaceIndex uint32, blackhole
if err != nil {
return err
}
bind.blackhole4 = blackhole
s.blackhole4 = blackhole
return nil
}
func (bind *StdNetBind) BindSocketToInterface6(interfaceIndex uint32, blackhole bool) error {
bind.mu.Lock()
defer bind.mu.Unlock()
sysconn, err := bind.ipv6.SyscallConn()
func (s *StdNetBind) BindSocketToInterface6(interfaceIndex uint32, blackhole bool) error {
s.mu.Lock()
defer s.mu.Unlock()
sysconn, err := s.ipv6.SyscallConn()
if err != nil {
return err
}
@ -531,7 +548,7 @@ func (bind *StdNetBind) BindSocketToInterface6(interfaceIndex uint32, blackhole
if err != nil {
return err
}
bind.blackhole6 = blackhole
s.blackhole6 = blackhole
return nil
}

39
conn/bindtest/bindtest.go
View File

@ -89,32 +89,39 @@ func (c *ChannelBind) Close() error {
return nil
}
func (c *ChannelBind) BatchSize() int { return 1 }
func (c *ChannelBind) SetMark(mark uint32) error { return nil }
func (c *ChannelBind) makeReceiveFunc(ch chan []byte) conn.ReceiveFunc {
return func(b []byte) (n int, ep conn.Endpoint, err error) {
return func(buffs [][]byte, sizes []int, eps []conn.Endpoint) (n int, err error) {
select {
case <-c.closeSignal:
return 0, nil, net.ErrClosed
return 0, net.ErrClosed
case rx := <-ch:
return copy(b, rx), c.target6, nil
copied := copy(buffs[0], rx)
sizes[0] = copied
eps[0] = c.target6
return 1, nil
}
}
}
func (c *ChannelBind) Send(b []byte, ep conn.Endpoint) error {
select {
case <-c.closeSignal:
return net.ErrClosed
default:
bc := make([]byte, len(b))
copy(bc, b)
if ep.(ChannelEndpoint) == c.target4 {
*c.tx4 <- bc
} else if ep.(ChannelEndpoint) == c.target6 {
*c.tx6 <- bc
} else {
return os.ErrInvalid
func (c *ChannelBind) Send(buffs [][]byte, ep conn.Endpoint) error {
for _, b := range buffs {
select {
case <-c.closeSignal:
return net.ErrClosed
default:
bc := make([]byte, len(b))
copy(bc, b)
if ep.(ChannelEndpoint) == c.target4 {
*c.tx4 <- bc
} else if ep.(ChannelEndpoint) == c.target6 {
*c.tx6 <- bc
} else {
return os.ErrInvalid
}
}
}
return nil

24
conn/conn.go
View File

@ -15,10 +15,17 @@ import (
"strings"
)
// A ReceiveFunc receives a single inbound packet from the network.
// It writes the data into b. n is the length of the packet.
// ep is the remote endpoint.
type ReceiveFunc func(b []byte) (n int, ep Endpoint, err error)
const (
DefaultBatchSize = 1 // maximum number of packets handled per read and write
)
// A ReceiveFunc receives at least one packet from the network and writes them
// into packets. On a successful read it returns the number of elements of
// sizes, packets, and endpoints that should be evaluated. Some elements of
// sizes may be zero, and callers should ignore them. Callers must pass a sizes
// and eps slice with a length greater than or equal to the length of packets.
// These lengths must not exceed the length of the associated Bind.BatchSize().
type ReceiveFunc func(packets [][]byte, sizes []int, eps []Endpoint) (n int, err error)
// A Bind listens on a port for both IPv6 and IPv4 UDP traffic.
//
@ -38,11 +45,16 @@ type Bind interface {
// This mark is passed to the kernel as the socket option SO_MARK.
SetMark(mark uint32) error
// Send writes a packet b to address ep.
Send(b []byte, ep Endpoint) error
// Send writes one or more packets in buffs to address ep. The length of
// buffs must not exceed BatchSize().
Send(buffs [][]byte, ep Endpoint) error
// ParseEndpoint creates a new endpoint from a string.
ParseEndpoint(s string) (Endpoint, error)
// BatchSize is the number of buffers expected to be passed to
// the ReceiveFuncs, and the maximum expected to be passed to SendBatch.
BatchSize() int
}
// BindSocketToInterface is implemented by Bind objects that support being

24
conn/conn_test.go Normal file
View File

@ -0,0 +1,24 @@
/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
*/
package conn
import (
"testing"
)
func TestPrettyName(t *testing.T) {
var (
recvFunc ReceiveFunc = func(buffs [][]byte, sizes []int, eps []Endpoint) (n int, err error) { return }
)
const want = "TestPrettyName"
t.Run("ReceiveFunc.PrettyName", func(t *testing.T) {
if got := recvFunc.PrettyName(); got != want {
t.Errorf("PrettyName() = %v, want %v", got, want)
}
})
}

30
device/channels.go
View File

@ -72,7 +72,7 @@ func newHandshakeQueue() *handshakeQueue {
}
type autodrainingInboundQueue struct {
c chan *QueueInboundElement
c chan *[]*QueueInboundElement
}
// newAutodrainingInboundQueue returns a channel that will be drained when it gets GC'd.
@ -81,7 +81,7 @@ type autodrainingInboundQueue struct {
// some other means, such as sending a sentinel nil values.
func newAutodrainingInboundQueue(device *Device) *autodrainingInboundQueue {
q := &autodrainingInboundQueue{
c: make(chan *QueueInboundElement, QueueInboundSize),
c: make(chan *[]*QueueInboundElement, QueueInboundSize),
}
runtime.SetFinalizer(q, device.flushInboundQueue)
return q
@ -90,10 +90,13 @@ func newAutodrainingInboundQueue(device *Device) *autodrainingInboundQueue {
func (device *Device) flushInboundQueue(q *autodrainingInboundQueue) {
for {
select {
case elem := <-q.c:
elem.Lock()
device.PutMessageBuffer(elem.buffer)
device.PutInboundElement(elem)
case elems := <-q.c:
for _, elem := range *elems {
elem.Lock()
device.PutMessageBuffer(elem.buffer)
device.PutInboundElement(elem)
}
device.PutInboundElementsSlice(elems)
default:
return
}
@ -101,7 +104,7 @@ func (device *Device) flushInboundQueue(q *autodrainingInboundQueue) {
}
type autodrainingOutboundQueue struct {
c chan *QueueOutboundElement
c chan *[]*QueueOutboundElement
}
// newAutodrainingOutboundQueue returns a channel that will be drained when it gets GC'd.
@ -111,7 +114,7 @@ type autodrainingOutboundQueue struct {
// All sends to the channel must be best-effort, because there may be no receivers.
func newAutodrainingOutboundQueue(device *Device) *autodrainingOutboundQueue {
q := &autodrainingOutboundQueue{
c: make(chan *QueueOutboundElement, QueueOutboundSize),
c: make(chan *[]*QueueOutboundElement, QueueOutboundSize),
}
runtime.SetFinalizer(q, device.flushOutboundQueue)
return q
@ -120,10 +123,13 @@ func newAutodrainingOutboundQueue(device *Device) *autodrainingOutboundQueue {
func (device *Device) flushOutboundQueue(q *autodrainingOutboundQueue) {
for {
select {
case elem := <-q.c:
elem.Lock()
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
case elems := <-q.c:
for _, elem := range *elems {
elem.Lock()
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
}
device.PutOutboundElementsSlice(elems)
default:
return
}

27
device/device.go
View File

@ -68,9 +68,11 @@ type Device struct {
cookieChecker CookieChecker
pool struct {
messageBuffers *WaitPool
inboundElements *WaitPool
outboundElements *WaitPool
outboundElementsSlice *WaitPool
inboundElementsSlice *WaitPool
messageBuffers *WaitPool
inboundElements *WaitPool
outboundElements *WaitPool
}
queue struct {
@ -295,6 +297,7 @@ func NewDevice(tunDevice tun.Device, bind conn.Bind, logger *Logger) *Device {
device.peers.keyMap = make(map[NoisePublicKey]*Peer)
device.rate.limiter.Init()
device.indexTable.Init()
device.PopulatePools()
// create queues
@ -322,6 +325,19 @@ func NewDevice(tunDevice tun.Device, bind conn.Bind, logger *Logger) *Device {
return device
}
// BatchSize returns the BatchSize for the device as a whole which is the max of
// the bind batch size and the tun batch size. The batch size reported by device
// is the size used to construct memory pools, and is the allowed batch size for
// the lifetime of the device.
func (device *Device) BatchSize() int {
size := device.net.bind.BatchSize()
dSize := device.tun.device.BatchSize()
if size < dSize {
size = dSize
}
return size
}
func (device *Device) LookupPeer(pk NoisePublicKey) *Peer {
device.peers.RLock()
defer device.peers.RUnlock()
@ -472,11 +488,13 @@ func (device *Device) BindUpdate() error {
var err error
var recvFns []conn.ReceiveFunc
netc := &device.net
recvFns, netc.port, err = netc.bind.Open(netc.port)
if err != nil {
netc.port = 0
return err
}
netc.netlinkCancel, err = device.startRouteListener(netc.bind)
if err != nil {
netc.bind.Close()
@ -507,8 +525,9 @@ func (device *Device) BindUpdate() error {
device.net.stopping.Add(len(recvFns))
device.queue.decryption.wg.Add(len(recvFns)) // each RoutineReceiveIncoming goroutine writes to device.queue.decryption
device.queue.handshake.wg.Add(len(recvFns)) // each RoutineReceiveIncoming goroutine writes to device.queue.handshake
batchSize := netc.bind.BatchSize()
for _, fn := range recvFns {
go device.RoutineReceiveIncoming(fn)
go device.RoutineReceiveIncoming(batchSize, fn)
}
device.log.Verbosef("UDP bind has been updated")

69
device/device_test.go
View File

@ -12,6 +12,7 @@ import (
"io"
"math/rand"
"net/netip"
"os"
"runtime"
"runtime/pprof"
"sync"
@ -21,6 +22,7 @@ import (
"golang.zx2c4.com/wireguard/conn"
"golang.zx2c4.com/wireguard/conn/bindtest"
"golang.zx2c4.com/wireguard/tun"
"golang.zx2c4.com/wireguard/tun/tuntest"
)
@ -307,6 +309,17 @@ func TestConcurrencySafety(t *testing.T) {
}
})
// Perform bind updates and keepalive sends concurrently with tunnel use.
t.Run("bindUpdate and keepalive", func(t *testing.T) {
const iters = 10
for i := 0; i < iters; i++ {
for _, peer := range pair {
peer.dev.BindUpdate()
peer.dev.SendKeepalivesToPeersWithCurrentKeypair()
}
}
})
close(done)
}
@ -405,3 +418,59 @@ func goroutineLeakCheck(t *testing.T) {
t.Fatalf("expected %d goroutines, got %d, leak?", startGoroutines, endGoroutines)
})
}
type fakeBindSized struct {
size int
}
func (b *fakeBindSized) Open(port uint16) (fns []conn.ReceiveFunc, actualPort uint16, err error) {
return nil, 0, nil
}
func (b *fakeBindSized) Close() error { return nil }
func (b *fakeBindSized) SetMark(mark uint32) error { return nil }
func (b *fakeBindSized) Send(buffs [][]byte, ep conn.Endpoint) error { return nil }
func (b *fakeBindSized) ParseEndpoint(s string) (conn.Endpoint, error) { return nil, nil }
func (b *fakeBindSized) BatchSize() int { return b.size }
type fakeTUNDeviceSized struct {
size int
}
func (t *fakeTUNDeviceSized) File() *os.File { return nil }
func (t *fakeTUNDeviceSized) Read(buffs [][]byte, sizes []int, offset int) (n int, err error) {
return 0, nil
}
func (t *fakeTUNDeviceSized) Write(buffs [][]byte, offset int) (int, error) { return 0, nil }
func (t *fakeTUNDeviceSized) MTU() (int, error) { return 0, nil }
func (t *fakeTUNDeviceSized) Name() (string, error) { return "", nil }
func (t *fakeTUNDeviceSized) Events() <-chan tun.Event { return nil }
func (t *fakeTUNDeviceSized) Close() error { return nil }
func (t *fakeTUNDeviceSized) BatchSize() int { return t.size }
func TestBatchSize(t *testing.T) {
d := Device{}
d.net.bind = &fakeBindSized{1}
d.tun.device = &fakeTUNDeviceSized{1}
if want, got := 1, d.BatchSize(); got != want {
t.Errorf("expected batch size %d, got %d", want, got)
}
d.net.bind = &fakeBindSized{1}
d.tun.device = &fakeTUNDeviceSized{128}
if want, got := 128, d.BatchSize(); got != want {
t.Errorf("expected batch size %d, got %d", want, got)
}
d.net.bind = &fakeBindSized{128}
d.tun.device = &fakeTUNDeviceSized{1}
if want, got := 128, d.BatchSize(); got != want {
t.Errorf("expected batch size %d, got %d", want, got)
}
d.net.bind = &fakeBindSized{128}
d.tun.device = &fakeTUNDeviceSized{128}
if want, got := 128, d.BatchSize(); got != want {
t.Errorf("expected batch size %d, got %d", want, got)
}
}

26
device/peer.go
View File

@ -45,9 +45,9 @@ type Peer struct {
}
queue struct {
staged chan *QueueOutboundElement // staged packets before a handshake is available
outbound *autodrainingOutboundQueue // sequential ordering of udp transmission
inbound *autodrainingInboundQueue // sequential ordering of tun writing
staged chan *[]*QueueOutboundElement // staged packets before a handshake is available
outbound *autodrainingOutboundQueue // sequential ordering of udp transmission
inbound *autodrainingInboundQueue // sequential ordering of tun writing
}
cookieGenerator CookieGenerator
@ -81,7 +81,7 @@ func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
peer.device = device
peer.queue.outbound = newAutodrainingOutboundQueue(device)
peer.queue.inbound = newAutodrainingInboundQueue(device)
peer.queue.staged = make(chan *QueueOutboundElement, QueueStagedSize)
peer.queue.staged = make(chan *[]*QueueOutboundElement, QueueStagedSize)
// map public key
_, ok := device.peers.keyMap[pk]
@ -108,7 +108,7 @@ func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
return peer, nil
}
func (peer *Peer) SendBuffer(buffer []byte) error {
func (peer *Peer) SendBuffers(buffers [][]byte) error {
peer.device.net.RLock()
defer peer.device.net.RUnlock()
@ -123,9 +123,13 @@ func (peer *Peer) SendBuffer(buffer []byte) error {
return errors.New("no known endpoint for peer")
}
err := peer.device.net.bind.Send(buffer, peer.endpoint)
err := peer.device.net.bind.Send(buffers, peer.endpoint)
if err == nil {
peer.txBytes.Add(uint64(len(buffer)))
var totalLen uint64
for _, b := range buffers {
totalLen += uint64(len(b))
}
peer.txBytes.Add(totalLen)
}
return err
}
@ -187,8 +191,12 @@ func (peer *Peer) Start() {
device.flushInboundQueue(peer.queue.inbound)
device.flushOutboundQueue(peer.queue.outbound)
go peer.RoutineSequentialSender()
go peer.RoutineSequentialReceiver()
// Use the device batch size, not the bind batch size, as the device size is
// the size of the batch pools.
batchSize := peer.device.BatchSize()
go peer.RoutineSequentialSender(batchSize)
go peer.RoutineSequentialReceiver(batchSize)
peer.isRunning.Store(true)
}

32
device/pools.go
View File

@ -46,6 +46,14 @@ func (p *WaitPool) Put(x any) {
}
func (device *Device) PopulatePools() {
device.pool.outboundElementsSlice = NewWaitPool(PreallocatedBuffersPerPool, func() any {
s := make([]*QueueOutboundElement, 0, device.BatchSize())
return &s
})
device.pool.inboundElementsSlice = NewWaitPool(PreallocatedBuffersPerPool, func() any {
s := make([]*QueueInboundElement, 0, device.BatchSize())
return &s
})
device.pool.messageBuffers = NewWaitPool(PreallocatedBuffersPerPool, func() any {
return new([MaxMessageSize]byte)
})
@ -57,6 +65,30 @@ func (device *Device) PopulatePools() {
})
}
func (device *Device) GetOutboundElementsSlice() *[]*QueueOutboundElement {
return device.pool.outboundElementsSlice.Get().(*[]*QueueOutboundElement)
}
func (device *Device) PutOutboundElementsSlice(s *[]*QueueOutboundElement) {
for i := range *s {
(*s)[i] = nil
}
*s = (*s)[:0]
device.pool.outboundElementsSlice.Put(s)
}
func (device *Device) GetInboundElementsSlice() *[]*QueueInboundElement {
return device.pool.inboundElementsSlice.Get().(*[]*QueueInboundElement)
}
func (device *Device) PutInboundElementsSlice(s *[]*QueueInboundElement) {
for i := range *s {
(*s)[i] = nil
}
*s = (*s)[:0]
device.pool.inboundElementsSlice.Put(s)
}
func (device *Device) GetMessageBuffer() *[MaxMessageSize]byte {
return device.pool.messageBuffers.Get().(*[MaxMessageSize]byte)
}

48
device/pools_test.go
View File

@ -89,3 +89,51 @@ func BenchmarkWaitPool(b *testing.B) {
}
wg.Wait()
}
func BenchmarkWaitPoolEmpty(b *testing.B) {
var wg sync.WaitGroup
var trials atomic.Int32
trials.Store(int32(b.N))
workers := runtime.NumCPU() + 2
if workers-4 <= 0 {
b.Skip("Not enough cores")
}
p := NewWaitPool(0, func() any { return make([]byte, 16) })
wg.Add(workers)
b.ResetTimer()
for i := 0; i < workers; i++ {
go func() {
defer wg.Done()
for trials.Add(-1) > 0 {
x := p.Get()
time.Sleep(time.Duration(rand.Intn(100)) * time.Microsecond)
p.Put(x)
}
}()
}
wg.Wait()
}
func BenchmarkSyncPool(b *testing.B) {
var wg sync.WaitGroup
var trials atomic.Int32
trials.Store(int32(b.N))
workers := runtime.NumCPU() + 2
if workers-4 <= 0 {
b.Skip("Not enough cores")
}
p := sync.Pool{New: func() any { return make([]byte, 16) }}
wg.Add(workers)
b.ResetTimer()
for i := 0; i < workers; i++ {
go func() {
defer wg.Done()
for trials.Add(-1) > 0 {
x := p.Get()
time.Sleep(time.Duration(rand.Intn(100)) * time.Microsecond)
p.Put(x)
}
}()
}
wg.Wait()
}

350
device/receive.go
View File

@ -66,7 +66,7 @@ func (peer *Peer) keepKeyFreshReceiving() {
* Every time the bind is updated a new routine is started for
* IPv4 and IPv6 (separately)
*/
func (device *Device) RoutineReceiveIncoming(recv conn.ReceiveFunc) {
func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.ReceiveFunc) {
recvName := recv.PrettyName()
defer func() {
device.log.Verbosef("Routine: receive incoming %s - stopped", recvName)
@ -79,20 +79,33 @@ func (device *Device) RoutineReceiveIncoming(recv conn.ReceiveFunc) {
// receive datagrams until conn is closed
buffer := device.GetMessageBuffer()
var (
buffsArrs = make([]*[MaxMessageSize]byte, maxBatchSize)
buffs = make([][]byte, maxBatchSize)
err error
size int
endpoint conn.Endpoint
sizes = make([]int, maxBatchSize)
count int
endpoints = make([]conn.Endpoint, maxBatchSize)
deathSpiral int
elemsByPeer = make(map[*Peer]*[]*QueueInboundElement, maxBatchSize)
)
for {
size, endpoint, err = recv(buffer[:])
for i := range buffsArrs {
buffsArrs[i] = device.GetMessageBuffer()
buffs[i] = buffsArrs[i][:]
}
defer func() {
for i := 0; i < maxBatchSize; i++ {
if buffsArrs[i] != nil {
device.PutMessageBuffer(buffsArrs[i])
}
}
}()
for {
count, err = recv(buffs, sizes, endpoints)
if err != nil {
device.PutMessageBuffer(buffer)
if errors.Is(err, net.ErrClosed) {
return
}
@ -103,101 +116,122 @@ func (device *Device) RoutineReceiveIncoming(recv conn.ReceiveFunc) {
if deathSpiral < 10 {
deathSpiral++
time.Sleep(time.Second / 3)
buffer = device.GetMessageBuffer()
continue
}
return
}
deathSpiral = 0
if size < MinMessageSize {
continue
}
// check size of packet
packet := buffer[:size]
msgType := binary.LittleEndian.Uint32(packet[:4])
var okay bool
switch msgType {
// check if transport
case MessageTransportType:
// check size
if len(packet) < MessageTransportSize {
// handle each packet in the batch
for i, size := range sizes[:count] {
if size < MinMessageSize {
continue
}
// lookup key pair
// check size of packet
receiver := binary.LittleEndian.Uint32(
packet[MessageTransportOffsetReceiver:MessageTransportOffsetCounter],
)
value := device.indexTable.Lookup(receiver)
keypair := value.keypair
if keypair == nil {
packet := buffsArrs[i][:size]
msgType := binary.LittleEndian.Uint32(packet[:4])
switch msgType {
// check if transport
case MessageTransportType:
// check size
if len(packet) < MessageTransportSize {
continue
}
// lookup key pair
receiver := binary.LittleEndian.Uint32(
packet[MessageTransportOffsetReceiver:MessageTransportOffsetCounter],
)
value := device.indexTable.Lookup(receiver)
keypair := value.keypair
if keypair == nil {
continue
}
// check keypair expiry
if keypair.created.Add(RejectAfterTime).Before(time.Now()) {
continue
}
// create work element
peer := value.peer
elem := device.GetInboundElement()
elem.packet = packet
elem.buffer = buffsArrs[i]
elem.keypair = keypair
elem.endpoint = endpoints[i]
elem.counter = 0
elem.Mutex = sync.Mutex{}
elem.Lock()
elemsForPeer, ok := elemsByPeer[peer]
if !ok {
elemsForPeer = device.GetInboundElementsSlice()
elemsByPeer[peer] = elemsForPeer
}
*elemsForPeer = append(*elemsForPeer, elem)
buffsArrs[i] = device.GetMessageBuffer()
buffs[i] = buffsArrs[i][:]
continue
// otherwise it is a fixed size & handshake related packet
case MessageInitiationType:
if len(packet) != MessageInitiationSize {
continue
}
case MessageResponseType:
if len(packet) != MessageResponseSize {
continue
}
case MessageCookieReplyType:
if len(packet) != MessageCookieReplySize {
continue
}
default:
device.log.Verbosef("Received message with unknown type")
continue
}
// check keypair expiry
if keypair.created.Add(RejectAfterTime).Before(time.Now()) {
continue
}
// create work element
peer := value.peer
elem := device.GetInboundElement()
elem.packet = packet
elem.buffer = buffer
elem.keypair = keypair
elem.endpoint = endpoint
elem.counter = 0
elem.Mutex = sync.Mutex{}
elem.Lock()
// add to decryption queues
if peer.isRunning.Load() {
peer.queue.inbound.c <- elem
device.queue.decryption.c <- elem
buffer = device.GetMessageBuffer()
} else {
device.PutInboundElement(elem)
}
continue
// otherwise it is a fixed size & handshake related packet
case MessageInitiationType:
okay = len(packet) == MessageInitiationSize
case MessageResponseType:
okay = len(packet) == MessageResponseSize
case MessageCookieReplyType:
okay = len(packet) == MessageCookieReplySize
default:
device.log.Verbosef("Received message with unknown type")
}
if okay {
select {
case device.queue.handshake.c <- QueueHandshakeElement{
msgType: msgType,
buffer: buffer,
buffer: buffsArrs[i],
packet: packet,
endpoint: endpoint,
endpoint: endpoints[i],
}:
buffer = device.GetMessageBuffer()
buffsArrs[i] = device.GetMessageBuffer()
buffs[i] = buffsArrs[i][:]
default:
}
}
for peer, elems := range elemsByPeer {
if peer.isRunning.Load() {
peer.queue.inbound.c <- elems
for _, elem := range *elems {
device.queue.decryption.c <- elem
}
} else {
for _, elem := range *elems {
device.PutMessageBuffer(elem.buffer)
device.PutInboundElement(elem)
}
device.PutInboundElementsSlice(elems)
}
delete(elemsByPeer, peer)
}
}
}
@ -393,7 +427,7 @@ func (device *Device) RoutineHandshake(id int) {
}
}
func (peer *Peer) RoutineSequentialReceiver() {
func (peer *Peer) RoutineSequentialReceiver(maxBatchSize int) {
device := peer.device
defer func() {
device.log.Verbosef("%v - Routine: sequential receiver - stopped", peer)
@ -401,89 +435,91 @@ func (peer *Peer) RoutineSequentialReceiver() {
}()
device.log.Verbosef("%v - Routine: sequential receiver - started", peer)
for elem := range peer.queue.inbound.c {
if elem == nil {
buffs := make([][]byte, 0, maxBatchSize)
for elems := range peer.queue.inbound.c {
if elems == nil {
return
}
var err error
elem.Lock()
if elem.packet == nil {
// decryption failed
goto skip
}
if !elem.keypair.replayFilter.ValidateCounter(elem.counter, RejectAfterMessages) {
goto skip
}
peer.SetEndpointFromPacket(elem.endpoint)
if peer.ReceivedWithKeypair(elem.keypair) {
peer.timersHandshakeComplete()
peer.SendStagedPackets()
}
peer.keepKeyFreshReceiving()
peer.timersAnyAuthenticatedPacketTraversal()
peer.timersAnyAuthenticatedPacketReceived()
peer.rxBytes.Add(uint64(len(elem.packet) + MinMessageSize))
if len(elem.packet) == 0 {
device.log.Verbosef("%v - Receiving keepalive packet", peer)
goto skip
}
peer.timersDataReceived()
switch elem.packet[0] >> 4 {
case ipv4.Version:
if len(elem.packet) < ipv4.HeaderLen {
goto skip
}
field := elem.packet[IPv4offsetTotalLength : IPv4offsetTotalLength+2]
length := binary.BigEndian.Uint16(field)
if int(length) > len(elem.packet) || int(length) < ipv4.HeaderLen {
goto skip
}
elem.packet = elem.packet[:length]
src := elem.packet[IPv4offsetSrc : IPv4offsetSrc+net.IPv4len]
if device.allowedips.Lookup(src) != peer {
device.log.Verbosef("IPv4 packet with disallowed source address from %v", peer)
goto skip
for _, elem := range *elems {
elem.Lock()
if elem.packet == nil {
// decryption failed
continue
}
case ipv6.Version:
if len(elem.packet) < ipv6.HeaderLen {
goto skip
}
field := elem.packet[IPv6offsetPayloadLength : IPv6offsetPayloadLength+2]
length := binary.BigEndian.Uint16(field)
length += ipv6.HeaderLen
if int(length) > len(elem.packet) {
goto skip
}
elem.packet = elem.packet[:length]
src := elem.packet[IPv6offsetSrc : IPv6offsetSrc+net.IPv6len]
if device.allowedips.Lookup(src) != peer {
device.log.Verbosef("IPv6 packet with disallowed source address from %v", peer)
goto skip
if !elem.keypair.replayFilter.ValidateCounter(elem.counter, RejectAfterMessages) {
continue
}
default:
device.log.Verbosef("Packet with invalid IP version from %v", peer)
goto skip
}
peer.SetEndpointFromPacket(elem.endpoint)
if peer.ReceivedWithKeypair(elem.keypair) {
peer.timersHandshakeComplete()
peer.SendStagedPackets()
}
peer.keepKeyFreshReceiving()
peer.timersAnyAuthenticatedPacketTraversal()
peer.timersAnyAuthenticatedPacketReceived()
peer.rxBytes.Add(uint64(len(elem.packet) + MinMessageSize))
_, err = device.tun.device.Write(elem.buffer[:MessageTransportOffsetContent+len(elem.packet)], MessageTransportOffsetContent)
if err != nil && !device.isClosed() {
device.log.Errorf("Failed to write packet to TUN device: %v", err)
if len(elem.packet) == 0 {
device.log.Verbosef("%v - Receiving keepalive packet", peer)
continue
}
peer.timersDataReceived()
switch elem.packet[0] >> 4 {
case 4:
if len(elem.packet) < ipv4.HeaderLen {
continue
}
field := elem.packet[IPv4offsetTotalLength : IPv4offsetTotalLength+2]
length := binary.BigEndian.Uint16(field)
if int(length) > len(elem.packet) || int(length) < ipv4.HeaderLen {
continue
}
elem.packet = elem.packet[:length]
src := elem.packet[IPv4offsetSrc : IPv4offsetSrc+net.IPv4len]
if device.allowedips.Lookup(src) != peer {
device.log.Verbosef("IPv4 packet with disallowed source address from %v", peer)
continue
}
case 6:
if len(elem.packet) < ipv6.HeaderLen {
continue
}
field := elem.packet[IPv6offsetPayloadLength : IPv6offsetPayloadLength+2]
length := binary.BigEndian.Uint16(field)
length += ipv6.HeaderLen
if int(length) > len(elem.packet) {
continue
}
elem.packet = elem.packet[:length]
src := elem.packet[IPv6offsetSrc : IPv6offsetSrc+net.IPv6len]
if device.allowedips.Lookup(src) != peer {
device.log.Verbosef("IPv6 packet with disallowed source address from %v", peer)
continue
}
default:
device.log.Verbosef("Packet with invalid IP version from %v", peer)
continue
}
buffs = append(buffs, elem.buffer[:MessageTransportOffsetContent+len(elem.packet)])
}
if len(peer.queue.inbound.c) == 0 {
err = device.tun.device.Flush()
if err != nil {
peer.device.log.Errorf("Unable to flush packets: %v", err)
if len(buffs) > 0 {
_, err := device.tun.device.Write(buffs, MessageTransportOffsetContent)
if err != nil && !device.isClosed() {
device.log.Errorf("Failed to write packets to TUN device: %v", err)
}
}
skip:
device.PutMessageBuffer(elem.buffer)
device.PutInboundElement(elem)
for _, elem := range *elems {
device.PutMessageBuffer(elem.buffer)
device.PutInboundElement(elem)
}
buffs = buffs[:0]
device.PutInboundElementsSlice(elems)
}
}

280
device/send.go
View File

@ -17,6 +17,7 @@ import (
"golang.org/x/crypto/chacha20poly1305"
"golang.org/x/net/ipv4"
"golang.org/x/net/ipv6"
"golang.zx2c4.com/wireguard/tun"
)
/* Outbound flow
@ -77,12 +78,15 @@ func (elem *QueueOutboundElement) clearPointers() {
func (peer *Peer) SendKeepalive() {
if len(peer.queue.staged) == 0 && peer.isRunning.Load() {
elem := peer.device.NewOutboundElement()
elems := peer.device.GetOutboundElementsSlice()
*elems = append(*elems, elem)
select {
case peer.queue.staged <- elem:
case peer.queue.staged <- elems:
peer.device.log.Verbosef("%v - Sending keepalive packet", peer)
default:
peer.device.PutMessageBuffer(elem.buffer)
peer.device.PutOutboundElement(elem)
peer.device.PutOutboundElementsSlice(elems)
}
}
peer.SendStagedPackets()
@ -125,7 +129,7 @@ func (peer *Peer) SendHandshakeInitiation(isRetry bool) error {
peer.timersAnyAuthenticatedPacketTraversal()
peer.timersAnyAuthenticatedPacketSent()
err = peer.SendBuffer(packet)
err = peer.SendBuffers([][]byte{packet})
if err != nil {
peer.device.log.Errorf("%v - Failed to send handshake initiation: %v", peer, err)
}
@ -163,7 +167,8 @@ func (peer *Peer) SendHandshakeResponse() error {
peer.timersAnyAuthenticatedPacketTraversal()
peer.timersAnyAuthenticatedPacketSent()
err = peer.SendBuffer(packet)
// TODO: allocation could be avoided
err = peer.SendBuffers([][]byte{packet})
if err != nil {
peer.device.log.Errorf("%v - Failed to send handshake response: %v", peer, err)
}
@ -183,7 +188,8 @@ func (device *Device) SendHandshakeCookie(initiatingElem *QueueHandshakeElement)
var buff [MessageCookieReplySize]byte
writer := bytes.NewBuffer(buff[:0])
binary.Write(writer, binary.LittleEndian, reply)
device.net.bind.Send(writer.Bytes(), initiatingElem.endpoint)
// TODO: allocation could be avoided
device.net.bind.Send([][]byte{writer.Bytes()}, initiatingElem.endpoint)
return nil
}
@ -198,11 +204,6 @@ func (peer *Peer) keepKeyFreshSending() {
}
}
/* Reads packets from the TUN and inserts
* into staged queue for peer
*
* Obs. Single instance per TUN device
*/
func (device *Device) RoutineReadFromTUN() {
defer func() {
device.log.Verbosef("Routine: TUN reader - stopped")
@ -212,81 +213,123 @@ func (device *Device) RoutineReadFromTUN() {
device.log.Verbosef("Routine: TUN reader - started")
var elem *QueueOutboundElement
var (
batchSize = device.BatchSize()
readErr error
elems = make([]*QueueOutboundElement, batchSize)
buffs = make([][]byte, batchSize)
elemsByPeer = make(map[*Peer]*[]*QueueOutboundElement, batchSize)
count = 0
sizes = make([]int, batchSize)
offset = MessageTransportHeaderSize
)
for i := range elems {
elems[i] = device.NewOutboundElement()
buffs[i] = elems[i].buffer[:]
}
defer func() {
for _, elem := range elems {
if elem != nil {
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
}
}
}()
for {
if elem != nil {
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
// read packets
count, readErr = device.tun.device.Read(buffs, sizes, offset)
for i := 0; i < count; i++ {
if sizes[i] < 1 {
continue
}
elem := elems[i]
elem.packet = buffs[i][offset : offset+sizes[i]]
// lookup peer
var peer *Peer
switch elem.packet[0] >> 4 {
case 4:
if len(elem.packet) < ipv4.HeaderLen {
continue
}
dst := elem.packet[IPv4offsetDst : IPv4offsetDst+net.IPv4len]
peer = device.allowedips.Lookup(dst)
case 6:
if len(elem.packet) < ipv6.HeaderLen {
continue
}
dst := elem.packet[IPv6offsetDst : IPv6offsetDst+net.IPv6len]
peer = device.allowedips.Lookup(dst)
default:
device.log.Verbosef("Received packet with unknown IP version")
}
if peer == nil {
continue
}
elemsForPeer, ok := elemsByPeer[peer]
if !ok {
elemsForPeer = device.GetOutboundElementsSlice()
elemsByPeer[peer] = elemsForPeer
}
*elemsForPeer = append(*elemsForPeer, elem)
elems[i] = device.NewOutboundElement()
buffs[i] = elems[i].buffer[:]
}
elem = device.NewOutboundElement()
// read packet
for peer, elemsForPeer := range elemsByPeer {
if peer.isRunning.Load() {
peer.StagePackets(elemsForPeer)
peer.SendStagedPackets()
} else {
for _, elem := range *elemsForPeer {
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
}
device.PutOutboundElementsSlice(elemsForPeer)
}
delete(elemsByPeer, peer)
}
offset := MessageTransportHeaderSize
size, err := device.tun.device.Read(elem.buffer[:], offset)
if err != nil {
if readErr != nil {
if errors.Is(readErr, tun.ErrTooManySegments) {
// TODO: record stat for this
// This will happen if MSS is surprisingly small (< 576)
// coincident with reasonably high throughput.
device.log.Verbosef("Dropped some packets from multi-segment read: %v", readErr)
continue
}
if !device.isClosed() {
if !errors.Is(err, os.ErrClosed) {
device.log.Errorf("Failed to read packet from TUN device: %v", err)
if !errors.Is(readErr, os.ErrClosed) {
device.log.Errorf("Failed to read packet from TUN device: %v", readErr)
}
go device.Close()
}
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
return
}
if size == 0 || size > MaxContentSize {
continue
}
elem.packet = elem.buffer[offset : offset+size]
// lookup peer
var peer *Peer
switch elem.packet[0] >> 4 {
case ipv4.Version:
if len(elem.packet) < ipv4.HeaderLen {
continue
}
dst := elem.packet[IPv4offsetDst : IPv4offsetDst+net.IPv4len]
peer = device.allowedips.Lookup(dst)
case ipv6.Version:
if len(elem.packet) < ipv6.HeaderLen {
continue
}
dst := elem.packet[IPv6offsetDst : IPv6offsetDst+net.IPv6len]
peer = device.allowedips.Lookup(dst)
default:
device.log.Verbosef("Received packet with unknown IP version")
}
if peer == nil {
continue
}
if peer.isRunning.Load() {
peer.StagePacket(elem)
elem = nil
peer.SendStagedPackets()
}
}
}
func (peer *Peer) StagePacket(elem *QueueOutboundElement) {
func (peer *Peer) StagePackets(elems *[]*QueueOutboundElement) {
for {
select {
case peer.queue.staged <- elem:
case peer.queue.staged <- elems:
return
default:
}
select {
case tooOld := <-peer.queue.staged:
peer.device.PutMessageBuffer(tooOld.buffer)
peer.device.PutOutboundElement(tooOld)
for _, elem := range *tooOld {
peer.device.PutMessageBuffer(elem.buffer)
peer.device.PutOutboundElement(elem)
}
peer.device.PutOutboundElementsSlice(tooOld)
default:
}
}
@ -305,26 +348,55 @@ top:
}
for {
var elemsOOO *[]*QueueOutboundElement
select {
case elem := <-peer.queue.staged:
elem.peer = peer
elem.nonce = keypair.sendNonce.Add(1) - 1
if elem.nonce >= RejectAfterMessages {
keypair.sendNonce.Store(RejectAfterMessages)
peer.StagePacket(elem) // XXX: Out of order, but we can't front-load go chans
case elems := <-peer.queue.staged:
i := 0
for _, elem := range *elems {
elem.peer = peer
elem.nonce = keypair.sendNonce.Add(1) - 1
if elem.nonce >= RejectAfterMessages {
keypair.sendNonce.Store(RejectAfterMessages)
if elemsOOO == nil {
elemsOOO = peer.device.GetOutboundElementsSlice()
}
*elemsOOO = append(*elemsOOO, elem)
continue
} else {
(*elems)[i] = elem
i++
}
elem.keypair = keypair
elem.Lock()
}
*elems = (*elems)[:i]
if elemsOOO != nil {
peer.StagePackets(elemsOOO) // XXX: Out of order, but we can't front-load go chans
}
if len(*elems) == 0 {
peer.device.PutOutboundElementsSlice(elems)
goto top
}
elem.keypair = keypair
elem.Lock()
// add to parallel and sequential queue
if peer.isRunning.Load() {
peer.queue.outbound.c <- elem
peer.device.queue.encryption.c <- elem
peer.queue.outbound.c <- elems
for _, elem := range *elems {
peer.device.queue.encryption.c <- elem
}
} else {
peer.device.PutMessageBuffer(elem.buffer)
peer.device.PutOutboundElement(elem)
for _, elem := range *elems {
peer.device.PutMessageBuffer(elem.buffer)
peer.device.PutOutboundElement(elem)
}
peer.device.PutOutboundElementsSlice(elems)
}
if elemsOOO != nil {
goto top
}
default:
return
@ -335,9 +407,12 @@ top:
func (peer *Peer) FlushStagedPackets() {
for {
select {
case elem := <-peer.queue.staged:
peer.device.PutMessageBuffer(elem.buffer)
peer.device.PutOutboundElement(elem)
case elems := <-peer.queue.staged:
for _, elem := range *elems {
peer.device.PutMessageBuffer(elem.buffer)
peer.device.PutOutboundElement(elem)
}
peer.device.PutOutboundElementsSlice(elems)
default:
return
}
@ -400,12 +475,7 @@ func (device *Device) RoutineEncryption(id int) {
}
}
/* Sequentially reads packets from queue and sends to endpoint
*
* Obs. Single instance per peer.
* The routine terminates then the outbound queue is closed.
*/
func (peer *Peer) RoutineSequentialSender() {
func (peer *Peer) RoutineSequentialSender(maxBatchSize int) {
device := peer.device
defer func() {
defer device.log.Verbosef("%v - Routine: sequential sender - stopped", peer)
@ -413,36 +483,50 @@ func (peer *Peer) RoutineSequentialSender() {
}()
device.log.Verbosef("%v - Routine: sequential sender - started", peer)
for elem := range peer.queue.outbound.c {
if elem == nil {
buffs := make([][]byte, 0, maxBatchSize)
for elems := range peer.queue.outbound.c {
buffs = buffs[:0]
if elems == nil {
return
}
elem.Lock()
if !peer.isRunning.Load() {
// peer has been stopped; return re-usable elems to the shared pool.
// This is an optimization only. It is possible for the peer to be stopped
// immediately after this check, in which case, elem will get processed.
// The timers and SendBuffer code are resilient to a few stragglers.
// The timers and SendBuffers code are resilient to a few stragglers.
// TODO: rework peer shutdown order to ensure
// that we never accidentally keep timers alive longer than necessary.
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
for _, elem := range *elems {
elem.Lock()
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
}
continue
}
dataSent := false
for _, elem := range *elems {
elem.Lock()
if len(elem.packet) != MessageKeepaliveSize {
dataSent = true
}
buffs = append(buffs, elem.packet)
}
peer.timersAnyAuthenticatedPacketTraversal()
peer.timersAnyAuthenticatedPacketSent()
// send message and return buffer to pool
err := peer.SendBuffer(elem.packet)
if len(elem.packet) != MessageKeepaliveSize {
err := peer.SendBuffers(buffs)
if dataSent {
peer.timersDataSent()
}
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
for _, elem := range *elems {
device.PutMessageBuffer(elem.buffer)
device.PutOutboundElement(elem)
}
device.PutOutboundElementsSlice(elems)
if err != nil {
device.log.Errorf("%v - Failed to send data packet: %v", peer, err)
device.log.Errorf("%v - Failed to send data packets: %v", peer, err)
continue
}

14
main.go
View File

@ -13,8 +13,8 @@ import (
"os/signal"
"runtime"
"strconv"
"syscall"
"golang.org/x/sys/unix"
"golang.zx2c4.com/wireguard/conn"
"golang.zx2c4.com/wireguard/device"
"golang.zx2c4.com/wireguard/ipc"
@ -111,7 +111,7 @@ func main() {
// open TUN device (or use supplied fd)
tun, err := func() (tun.Device, error) {
tdev, err := func() (tun.Device, error) {
tunFdStr := os.Getenv(ENV_WG_TUN_FD)
if tunFdStr == "" {
return tun.CreateTUN(interfaceName, device.DefaultMTU)
@ -124,7 +124,7 @@ func main() {
return nil, err
}
err = syscall.SetNonblock(int(fd), true)
err = unix.SetNonblock(int(fd), true)
if err != nil {
return nil, err
}
@ -134,7 +134,7 @@ func main() {
}()
if err == nil {
realInterfaceName, err2 := tun.Name()
realInterfaceName, err2 := tdev.Name()
if err2 == nil {
interfaceName = realInterfaceName
}
@ -196,7 +196,7 @@ func main() {
files[0], // stdin
files[1], // stdout
files[2], // stderr
tun.File(),
tdev.File(),
fileUAPI,
},
Dir: ".",
@ -222,7 +222,7 @@ func main() {
return
}
device := device.NewDevice(tun, conn.NewDefaultBind(), logger)
device := device.NewDevice(tdev, conn.NewDefaultBind(), logger)
logger.Verbosef("Device started")
@ -250,7 +250,7 @@ func main() {
// wait for program to terminate
signal.Notify(term, syscall.SIGTERM)
signal.Notify(term, unix.SIGTERM)
signal.Notify(term, os.Interrupt)
select {

5
main_windows.go
View File

@ -9,7 +9,8 @@ import (
"fmt"
"os"
"os/signal"
"syscall"
"golang.org/x/sys/windows"
"golang.zx2c4.com/wireguard/conn"
"golang.zx2c4.com/wireguard/device"
@ -81,7 +82,7 @@ func main() {
signal.Notify(term, os.Interrupt)
signal.Notify(term, os.Kill)
signal.Notify(term, syscall.SIGTERM)
signal.Notify(term, windows.SIGTERM)
select {
case <-term:

60
tun/errors.go Normal file
View File

@ -0,0 +1,60 @@
package tun
import (
"errors"
"fmt"
)
var (
// ErrTooManySegments is returned by Device.Read() when segmentation
// overflows the length of supplied buffers. This error should not cause
// reads to cease.
ErrTooManySegments = errors.New("too many segments")
)
type errorBatch []error
// ErrorBatch takes a possibly nil or empty list of errors, and if the list is
// non-nil returns an error type that wraps all of the errors. Expected usage is
// to append to an []errors and coerce the set to an error using this method.
func ErrorBatch(errs []error) error {
if len(errs) == 0 {
return nil
}
return errorBatch(errs)
}
func (e errorBatch) Error() string {
if len(e) == 0 {
return ""
}
if len(e) == 1 {
return e[0].Error()
}
return fmt.Sprintf("batch operation: %v (and %d more errors)", e[0], len(e)-1)
}
func (e errorBatch) Is(target error) bool {
for _, err := range e {
if errors.Is(err, target) {
return true
}
}
return false
}
func (e errorBatch) As(target interface{}) bool {
for _, err := range e {
if errors.As(err, target) {
return true
}
}
return false
}
func (e errorBatch) Unwrap() error {
if len(e) == 0 {
return nil
}
return e[0]
}

45
tun/netstack/tun.go
View File

@ -19,6 +19,7 @@ import (
"regexp"
"strconv"
"strings"
"syscall"
"time"
"golang.zx2c4.com/wireguard/tun"
@ -113,29 +114,37 @@ func (tun *netTun) Events() <-chan tun.Event {
return tun.events
}
func (tun *netTun) Read(buf []byte, offset int) (int, error) {
func (tun *netTun) Read(buf [][]byte, sizes []int, offset int) (int, error) {
view, ok := <-tun.incomingPacket
if !ok {
return 0, os.ErrClosed
}
return view.Read(buf[offset:])
n, err := view.Read(buf[0][offset:])
if err != nil {
return 0, err
}
sizes[0] = n
return 1, nil
}
func (tun *netTun) Write(buf []byte, offset int) (int, error) {
packet := buf[offset:]
if len(packet) == 0 {
return 0, nil
}
func (tun *netTun) Write(buf [][]byte, offset int) (int, error) {
for _, buf := range buf {
packet := buf[offset:]
if len(packet) == 0 {
continue
}
pkb := stack.NewPacketBuffer(stack.PacketBufferOptions{Payload: bufferv2.MakeWithData(packet)})
switch packet[0] >> 4 {
case 4:
tun.ep.InjectInbound(header.IPv4ProtocolNumber, pkb)
case 6:
tun.ep.InjectInbound(header.IPv6ProtocolNumber, pkb)
pkb := stack.NewPacketBuffer(stack.PacketBufferOptions{Payload: bufferv2.MakeWithData(packet)})
switch packet[0] >> 4 {
case 4:
tun.ep.InjectInbound(header.IPv4ProtocolNumber, pkb)
case 6:
tun.ep.InjectInbound(header.IPv6ProtocolNumber, pkb)
default:
return 0, syscall.EAFNOSUPPORT
}
}
return len(buf), nil
}
@ -151,10 +160,6 @@ func (tun *netTun) WriteNotify() {
tun.incomingPacket <- view
}
func (tun *netTun) Flush() error {
return nil
}
func (tun *netTun) Close() error {
tun.stack.RemoveNIC(1)
@ -175,6 +180,10 @@ func (tun *netTun) MTU() (int, error) {
return tun.mtu, nil
}
func (tun *netTun) BatchSize() int {
return 1
}
func convertToFullAddr(endpoint netip.AddrPort) (tcpip.FullAddress, tcpip.NetworkProtocolNumber) {
var protoNumber tcpip.NetworkProtocolNumber
if endpoint.Addr().Is4() {

40
tun/tun.go
View File

@ -18,12 +18,36 @@ const (
)
type Device interface {
File() *os.File // returns the file descriptor of the device
Read([]byte, int) (int, error) // read a packet from the device (without any additional headers)
Write([]byte, int) (int, error) // writes a packet to the device (without any additional headers)
Flush() error // flush all previous writes to the device
MTU() (int, error) // returns the MTU of the device
Name() (string, error) // fetches and returns the current name
Events() <-chan Event // returns a constant channel of events related to the device
Close() error // stops the device and closes the event channel
// File returns the file descriptor of the device.
File() *os.File
// Read one or more packets from the Device (without any additional headers).
// On a successful read it returns the number of packets read, and sets
// packet lengths within the sizes slice. len(sizes) must be >= len(buffs).
// A nonzero offset can be used to instruct the Device on where to begin
// reading into each element of the buffs slice.
Read(buffs [][]byte, sizes []int, offset int) (n int, err error)
// Write one or more packets to the device (without any additional headers).
// On a successful write it returns the number of packets written. A nonzero
// offset can be used to instruct the Device on where to begin writing from
// each packet contained within the buffs slice.
Write(buffs [][]byte, offset int) (int, error)
// MTU returns the MTU of the Device.
MTU() (int, error)
// Name returns the current name of the Device.
Name() (string, error)
// Events returns a channel of type Event, which is fed Device events.
Events() <-chan Event
// Close stops the Device and closes the Event channel.
Close() error
// BatchSize returns the preferred/max number of packets that can be read or
// written in a single read/write call. BatchSize must not change over the
// lifetime of a Device.
BatchSize() int
}

65
tun/tun_darwin.go
View File

@ -8,6 +8,7 @@ package tun
import (
"errors"
"fmt"
"io"
"net"
"os"
"sync"
@ -15,7 +16,6 @@ import (
"time"
"unsafe"
"golang.org/x/net/ipv6"
"golang.org/x/sys/unix"
)
@ -33,7 +33,7 @@ type NativeTun struct {
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, syscall.ENOMEM) {
if err != nil && errors.Is(err, unix.ENOMEM) {
time.Sleep(time.Duration(i) * time.Second / 3)
continue
}
@ -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
@ -217,45 +217,46 @@ func (tun *NativeTun) Events() <-chan Event {
return tun.events
}
func (tun *NativeTun) Read(buff []byte, offset int) (int, error) {
func (tun *NativeTun) Read(buffs [][]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:]
buff := buffs[0][offset-4:]
n, err := tun.tunFile.Read(buff[:])
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(buffs [][]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 buffs {
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(buffs), nil
}
func (tun *NativeTun) Close() error {
@ -318,6 +319,10 @@ func (tun *NativeTun) MTU() (int, error) {
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()

53
tun/tun_freebsd.go
View File

@ -333,45 +333,46 @@ func (tun *NativeTun) Events() <-chan Event {
return tun.events
}
func (tun *NativeTun) Read(buff []byte, offset int) (int, error) {
func (tun *NativeTun) Read(buffs [][]byte, sizes []int, offset int) (int, error) {
select {
case err := <-tun.errors:
return 0, err
default:
buff := buff[offset-4:]
buff := buffs[0][offset-4:]
n, err := tun.tunFile.Read(buff[:])
if n < 4 {
return 0, err
}
return n - 4, err
sizes[0] = n - 4
return 1, err
}
}
func (tun *NativeTun) Write(buf []byte, offset int) (int, error) {
func (tun *NativeTun) Write(buffs [][]byte, offset int) (int, error) {
if offset < 4 {
return 0, io.ErrShortBuffer
}
buf = buf[offset-4:]
if len(buf) < 5 {
return 0, io.ErrShortBuffer
for i, buf := range buffs {
buf = buf[offset-4:]
if len(buf) < 5 {
return i, io.ErrShortBuffer
}
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
}
}
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 0, unix.EAFNOSUPPORT
}
return tun.tunFile.Write(buf)
}
func (tun *NativeTun) Flush() error {
// TODO: can flushing be implemented by buffering and using sendmmsg?
return nil
return len(buffs), nil
}
func (tun *NativeTun) Close() error {
@ -428,3 +429,7 @@ func (tun *NativeTun) MTU() (int, error) {
}
return int(*(*int32)(unsafe.Pointer(&ifr.MTU))), nil
}
func (tun *NativeTun) BatchSize() int {
return 1
}

39
tun/tun_linux.go
View File

@ -323,12 +323,13 @@ func (tun *NativeTun) nameSlow() (string, error) {
return unix.ByteSliceToString(ifr[:]), nil
}
func (tun *NativeTun) Write(buf []byte, offset int) (int, error) {
func (tun *NativeTun) Write(buffs [][]byte, offset int) (n int, err error) {
var buf []byte
if tun.nopi {
buf = buf[offset:]
buf = buffs[0][offset:]
} else {
// reserve space for header
buf = buf[offset-4:]
buf = buffs[0][offset-4:]
// add packet information header
buf[0] = 0x00
@ -342,34 +343,36 @@ func (tun *NativeTun) Write(buf []byte, offset int) (int, error) {
}
}
n, err := tun.tunFile.Write(buf)
_, err = tun.tunFile.Write(buf)
if errors.Is(err, syscall.EBADFD) {
err = os.ErrClosed
} else if err == nil {
n = 1
}
return n, err
}
func (tun *NativeTun) Flush() error {
// TODO: can flushing be implemented by buffering and using sendmmsg?
return nil
}
func (tun *NativeTun) Read(buf []byte, offset int) (n int, err error) {
func (tun *NativeTun) Read(buffs [][]byte, sizes []int, offset int) (n int, err error) {
select {
case err = <-tun.errors:
default:
if tun.nopi {
n, err = tun.tunFile.Read(buf[offset:])
sizes[0], err = tun.tunFile.Read(buffs[0][offset:])
if err == nil {
n = 1
}
} else {
buff := buf[offset-4:]
n, err = tun.tunFile.Read(buff[:])
buff := buffs[0][offset-4:]
sizes[0], err = tun.tunFile.Read(buff[:])
if errors.Is(err, syscall.EBADFD) {
err = os.ErrClosed
} else if err == nil {
n = 1
}
if n < 4 {
n = 0
if sizes[0] < 4 {
sizes[0] = 0
} else {
n -= 4
sizes[0] -= 4
}
}
}
@ -399,6 +402,10 @@ func (tun *NativeTun) Close() error {
return err2
}
func (tun *NativeTun) BatchSize() int {
return 1
}
func CreateTUN(name string, mtu int) (Device, error) {
nfd, err := unix.Open(cloneDevicePath, unix.O_RDWR|unix.O_CLOEXEC, 0)
if err != nil {

58
tun/tun_openbsd.go
View File

@ -8,13 +8,13 @@ package tun
import (
"errors"
"fmt"
"io"
"net"
"os"
"sync"
"syscall"
"unsafe"
"golang.org/x/net/ipv6"
"golang.org/x/sys/unix"
)
@ -204,45 +204,43 @@ func (tun *NativeTun) Events() <-chan Event {
return tun.events
}
func (tun *NativeTun) Read(buff []byte, offset int) (int, error) {
func (tun *NativeTun) Read(buffs [][]byte, sizes []int, offset int) (int, error) {
select {
case err := <-tun.errors:
return 0, err
default:
buff := buff[offset-4:]
buff := buffs[0][offset-4:]
n, err := tun.tunFile.Read(buff[:])
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(buffs [][]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 buffs {
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(buffs), nil
}
func (tun *NativeTun) Close() error {
@ -329,3 +327,7 @@ func (tun *NativeTun) MTU() (int, error) {
return int(*(*int32)(unsafe.Pointer(&ifr.MTU))), nil
}
func (tun *NativeTun) BatchSize() int {
return 1
}

52
tun/tun_windows.go
View File

@ -15,7 +15,6 @@ import (
_ "unsafe"
"golang.org/x/sys/windows"
"golang.zx2c4.com/wintun"
)
@ -44,6 +43,7 @@ type NativeTun struct {
closeOnce sync.Once
close atomic.Bool
forcedMTU int
outSizes []int
}
var (
@ -134,9 +134,14 @@ func (tun *NativeTun) ForceMTU(mtu int) {
}
}
func (tun *NativeTun) BatchSize() int {
// TODO: implement batching with wintun
return 1
}
// Note: Read() and Write() assume the caller comes only from a single thread; there's no locking.
func (tun *NativeTun) Read(buff []byte, offset int) (int, error) {
func (tun *NativeTun) Read(buffs [][]byte, sizes []int, offset int) (int, error) {
tun.running.Add(1)
defer tun.running.Done()
retry:
@ -153,10 +158,11 @@ retry:
switch err {
case nil:
packetSize := len(packet)
copy(buff[offset:], packet)
copy(buffs[0][offset:], packet)
sizes[0] = packetSize
tun.session.ReleaseReceivePacket(packet)
tun.rate.update(uint64(packetSize))
return packetSize, nil
return 1, nil
case windows.ERROR_NO_MORE_ITEMS:
if !shouldSpin || uint64(nanotime()-start) >= spinloopDuration {
windows.WaitForSingleObject(tun.readWait, windows.INFINITE)
@ -173,33 +179,33 @@ retry:
}
}
func (tun *NativeTun) Flush() error {
return nil
}
func (tun *NativeTun) Write(buff []byte, offset int) (int, error) {
func (tun *NativeTun) Write(buffs [][]byte, offset int) (int, error) {
tun.running.Add(1)
defer tun.running.Done()
if tun.close.Load() {
return 0, os.ErrClosed
}
packetSize := len(buff) - offset
tun.rate.update(uint64(packetSize))
for i, buff := range buffs {
packetSize := len(buff) - offset
tun.rate.update(uint64(packetSize))
packet, err := tun.session.AllocateSendPacket(packetSize)
if err == nil {
copy(packet, buff[offset:])
tun.session.SendPacket(packet)
return packetSize, nil
packet, err := tun.session.AllocateSendPacket(packetSize)
switch err {
case nil:
// TODO: Explore options to eliminate this copy.
copy(packet, buff[offset:])
tun.session.SendPacket(packet)
continue
case windows.ERROR_HANDLE_EOF:
return i, os.ErrClosed
case windows.ERROR_BUFFER_OVERFLOW:
continue // Dropping when ring is full.
default:
return i, fmt.Errorf("Write failed: %w", err)
}
}
switch err {
case windows.ERROR_HANDLE_EOF:
return 0, os.ErrClosed
case windows.ERROR_BUFFER_OVERFLOW:
return 0, nil // Dropping when ring is full.
}
return 0, fmt.Errorf("Write failed: %w", err)
return len(buffs), nil
}
// LUID returns Windows interface instance ID.

29
tun/tuntest/tuntest.go
View File

@ -110,35 +110,42 @@ type chTun struct {
func (t *chTun) File() *os.File { return nil }
func (t *chTun) Read(data []byte, offset int) (int, error) {
func (t *chTun) Read(packets [][]byte, sizes []int, offset int) (int, error) {
select {
case <-t.c.closed:
return 0, os.ErrClosed
case msg := <-t.c.Outbound:
return copy(data[offset:], msg), nil
n := copy(packets[0][offset:], msg)
sizes[0] = n
return 1, nil
}
}
// Write is called by the wireguard device to deliver a packet for routing.
func (t *chTun) Write(data []byte, offset int) (int, error) {
func (t *chTun) Write(packets [][]byte, offset int) (int, error) {
if offset == -1 {
close(t.c.closed)
close(t.c.events)
return 0, io.EOF
}
msg := make([]byte, len(data)-offset)
copy(msg, data[offset:])
select {
case <-t.c.closed:
return 0, os.ErrClosed
case t.c.Inbound <- msg:
return len(data) - offset, nil
for i, data := range packets {
msg := make([]byte, len(data)-offset)
copy(msg, data[offset:])
select {
case <-t.c.closed:
return i, os.ErrClosed
case t.c.Inbound <- msg:
}
}
return len(packets), nil
}
func (t *chTun) BatchSize() int {
return 1
}
const DefaultMTU = 1420
func (t *chTun) Flush() error { return nil }
func (t *chTun) MTU() (int, error) { return DefaultMTU, nil }
func (t *chTun) Name() (string, error) { return "loopbackTun1", nil }
func (t *chTun) Events() <-chan tun.Event { return t.c.events }