579 lines
12 KiB
Go
579 lines
12 KiB
Go
/* SPDX-License-Identifier: MIT
|
|
*
|
|
* Copyright (C) 2017-2021 WireGuard LLC. All Rights Reserved.
|
|
*/
|
|
|
|
package device
|
|
|
|
import (
|
|
"runtime"
|
|
"sync"
|
|
"sync/atomic"
|
|
"time"
|
|
|
|
"golang.org/x/net/ipv4"
|
|
"golang.org/x/net/ipv6"
|
|
"golang.zx2c4.com/wireguard/conn"
|
|
"golang.zx2c4.com/wireguard/ratelimiter"
|
|
"golang.zx2c4.com/wireguard/rwcancel"
|
|
"golang.zx2c4.com/wireguard/tun"
|
|
)
|
|
|
|
type Device struct {
|
|
isUp AtomicBool // device is (going) up
|
|
isClosed AtomicBool // device is closed? (acting as guard)
|
|
log *Logger
|
|
|
|
// synchronized resources (locks acquired in order)
|
|
|
|
state struct {
|
|
stopping sync.WaitGroup
|
|
sync.Mutex
|
|
changing AtomicBool
|
|
current bool
|
|
}
|
|
|
|
net struct {
|
|
stopping sync.WaitGroup
|
|
sync.RWMutex
|
|
bind conn.Bind // bind interface
|
|
netlinkCancel *rwcancel.RWCancel
|
|
port uint16 // listening port
|
|
fwmark uint32 // mark value (0 = disabled)
|
|
}
|
|
|
|
staticIdentity struct {
|
|
sync.RWMutex
|
|
privateKey NoisePrivateKey
|
|
publicKey NoisePublicKey
|
|
}
|
|
|
|
peers struct {
|
|
empty AtomicBool // empty reports whether len(keyMap) == 0
|
|
sync.RWMutex // protects keyMap
|
|
keyMap map[NoisePublicKey]*Peer
|
|
}
|
|
|
|
// unprotected / "self-synchronising resources"
|
|
|
|
allowedips AllowedIPs
|
|
indexTable IndexTable
|
|
cookieChecker CookieChecker
|
|
|
|
rate struct {
|
|
underLoadUntil atomic.Value
|
|
limiter ratelimiter.Ratelimiter
|
|
}
|
|
|
|
pool struct {
|
|
messageBufferPool *sync.Pool
|
|
messageBufferReuseChan chan *[MaxMessageSize]byte
|
|
inboundElementPool *sync.Pool
|
|
inboundElementReuseChan chan *QueueInboundElement
|
|
outboundElementPool *sync.Pool
|
|
outboundElementReuseChan chan *QueueOutboundElement
|
|
}
|
|
|
|
queue struct {
|
|
encryption *encryptionQueue
|
|
decryption *decryptionQueue
|
|
handshake chan QueueHandshakeElement
|
|
}
|
|
|
|
signals struct {
|
|
stop chan struct{}
|
|
}
|
|
|
|
tun struct {
|
|
device tun.Device
|
|
mtu int32
|
|
}
|
|
|
|
ipcMutex sync.RWMutex
|
|
}
|
|
|
|
// An encryptionQueue is a channel of QueueOutboundElements awaiting encryption.
|
|
// An encryptionQueue is ref-counted using its wg field.
|
|
// An encryptionQueue created with newEncryptionQueue has one reference.
|
|
// Every additional writer must call wg.Add(1).
|
|
// Every completed writer must call wg.Done().
|
|
// When no further writers will be added,
|
|
// call wg.Done to remove the initial reference.
|
|
// When the refcount hits 0, the queue's channel is closed.
|
|
type encryptionQueue struct {
|
|
c chan *QueueOutboundElement
|
|
wg sync.WaitGroup
|
|
}
|
|
|
|
func newEncryptionQueue() *encryptionQueue {
|
|
q := &encryptionQueue{
|
|
c: make(chan *QueueOutboundElement, QueueOutboundSize),
|
|
}
|
|
q.wg.Add(1)
|
|
go func() {
|
|
q.wg.Wait()
|
|
close(q.c)
|
|
}()
|
|
return q
|
|
}
|
|
|
|
// A decryptionQueue is similar to an encryptionQueue; see those docs.
|
|
type decryptionQueue struct {
|
|
c chan *QueueInboundElement
|
|
wg sync.WaitGroup
|
|
}
|
|
|
|
func newDecryptionQueue() *decryptionQueue {
|
|
q := &decryptionQueue{
|
|
c: make(chan *QueueInboundElement, QueueInboundSize),
|
|
}
|
|
q.wg.Add(1)
|
|
go func() {
|
|
q.wg.Wait()
|
|
close(q.c)
|
|
}()
|
|
return q
|
|
}
|
|
|
|
/* Converts the peer into a "zombie", which remains in the peer map,
|
|
* but processes no packets and does not exists in the routing table.
|
|
*
|
|
* Must hold device.peers.Mutex
|
|
*/
|
|
func unsafeRemovePeer(device *Device, peer *Peer, key NoisePublicKey) {
|
|
|
|
// stop routing and processing of packets
|
|
|
|
device.allowedips.RemoveByPeer(peer)
|
|
peer.Stop()
|
|
|
|
// remove from peer map
|
|
|
|
delete(device.peers.keyMap, key)
|
|
device.peers.empty.Set(len(device.peers.keyMap) == 0)
|
|
}
|
|
|
|
func deviceUpdateState(device *Device) {
|
|
|
|
// check if state already being updated (guard)
|
|
|
|
if device.state.changing.Swap(true) {
|
|
return
|
|
}
|
|
|
|
// compare to current state of device
|
|
|
|
device.state.Lock()
|
|
|
|
newIsUp := device.isUp.Get()
|
|
|
|
if newIsUp == device.state.current {
|
|
device.state.changing.Set(false)
|
|
device.state.Unlock()
|
|
return
|
|
}
|
|
|
|
// change state of device
|
|
|
|
switch newIsUp {
|
|
case true:
|
|
if err := device.BindUpdate(); err != nil {
|
|
device.log.Errorf("Unable to update bind: %v", err)
|
|
device.isUp.Set(false)
|
|
break
|
|
}
|
|
device.peers.RLock()
|
|
for _, peer := range device.peers.keyMap {
|
|
peer.Start()
|
|
if atomic.LoadUint32(&peer.persistentKeepaliveInterval) > 0 {
|
|
peer.SendKeepalive()
|
|
}
|
|
}
|
|
device.peers.RUnlock()
|
|
|
|
case false:
|
|
device.BindClose()
|
|
device.peers.RLock()
|
|
for _, peer := range device.peers.keyMap {
|
|
peer.Stop()
|
|
}
|
|
device.peers.RUnlock()
|
|
}
|
|
|
|
// update state variables
|
|
|
|
device.state.current = newIsUp
|
|
device.state.changing.Set(false)
|
|
device.state.Unlock()
|
|
|
|
// check for state change in the mean time
|
|
|
|
deviceUpdateState(device)
|
|
}
|
|
|
|
func (device *Device) Up() {
|
|
|
|
// closed device cannot be brought up
|
|
|
|
if device.isClosed.Get() {
|
|
return
|
|
}
|
|
|
|
device.isUp.Set(true)
|
|
deviceUpdateState(device)
|
|
}
|
|
|
|
func (device *Device) Down() {
|
|
device.isUp.Set(false)
|
|
deviceUpdateState(device)
|
|
}
|
|
|
|
func (device *Device) IsUnderLoad() bool {
|
|
|
|
// check if currently under load
|
|
|
|
now := time.Now()
|
|
underLoad := len(device.queue.handshake) >= UnderLoadQueueSize
|
|
if underLoad {
|
|
device.rate.underLoadUntil.Store(now.Add(UnderLoadAfterTime))
|
|
return true
|
|
}
|
|
|
|
// check if recently under load
|
|
|
|
until := device.rate.underLoadUntil.Load().(time.Time)
|
|
return until.After(now)
|
|
}
|
|
|
|
func (device *Device) SetPrivateKey(sk NoisePrivateKey) error {
|
|
// lock required resources
|
|
|
|
device.staticIdentity.Lock()
|
|
defer device.staticIdentity.Unlock()
|
|
|
|
if sk.Equals(device.staticIdentity.privateKey) {
|
|
return nil
|
|
}
|
|
|
|
device.peers.Lock()
|
|
defer device.peers.Unlock()
|
|
|
|
lockedPeers := make([]*Peer, 0, len(device.peers.keyMap))
|
|
for _, peer := range device.peers.keyMap {
|
|
peer.handshake.mutex.RLock()
|
|
lockedPeers = append(lockedPeers, peer)
|
|
}
|
|
|
|
// remove peers with matching public keys
|
|
|
|
publicKey := sk.publicKey()
|
|
for key, peer := range device.peers.keyMap {
|
|
if peer.handshake.remoteStatic.Equals(publicKey) {
|
|
peer.handshake.mutex.RUnlock()
|
|
unsafeRemovePeer(device, peer, key)
|
|
peer.handshake.mutex.RLock()
|
|
}
|
|
}
|
|
|
|
// update key material
|
|
|
|
device.staticIdentity.privateKey = sk
|
|
device.staticIdentity.publicKey = publicKey
|
|
device.cookieChecker.Init(publicKey)
|
|
|
|
// do static-static DH pre-computations
|
|
|
|
expiredPeers := make([]*Peer, 0, len(device.peers.keyMap))
|
|
for _, peer := range device.peers.keyMap {
|
|
handshake := &peer.handshake
|
|
handshake.precomputedStaticStatic = device.staticIdentity.privateKey.sharedSecret(handshake.remoteStatic)
|
|
expiredPeers = append(expiredPeers, peer)
|
|
}
|
|
|
|
for _, peer := range lockedPeers {
|
|
peer.handshake.mutex.RUnlock()
|
|
}
|
|
for _, peer := range expiredPeers {
|
|
peer.ExpireCurrentKeypairs()
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func NewDevice(tunDevice tun.Device, logger *Logger) *Device {
|
|
device := new(Device)
|
|
device.log = logger
|
|
device.tun.device = tunDevice
|
|
mtu, err := device.tun.device.MTU()
|
|
if err != nil {
|
|
device.log.Errorf("Trouble determining MTU, assuming default: %v", err)
|
|
mtu = DefaultMTU
|
|
}
|
|
device.tun.mtu = int32(mtu)
|
|
|
|
device.peers.keyMap = make(map[NoisePublicKey]*Peer)
|
|
|
|
device.rate.limiter.Init()
|
|
device.rate.underLoadUntil.Store(time.Time{})
|
|
|
|
device.indexTable.Init()
|
|
|
|
device.PopulatePools()
|
|
|
|
// create queues
|
|
|
|
device.queue.handshake = make(chan QueueHandshakeElement, QueueHandshakeSize)
|
|
device.queue.encryption = newEncryptionQueue()
|
|
device.queue.decryption = newDecryptionQueue()
|
|
|
|
// prepare signals
|
|
|
|
device.signals.stop = make(chan struct{})
|
|
|
|
// prepare net
|
|
|
|
device.net.port = 0
|
|
device.net.bind = nil
|
|
|
|
// start workers
|
|
|
|
cpus := runtime.NumCPU()
|
|
device.state.stopping.Wait()
|
|
for i := 0; i < cpus; i++ {
|
|
device.state.stopping.Add(2) // decryption and handshake
|
|
go device.RoutineEncryption()
|
|
go device.RoutineDecryption()
|
|
go device.RoutineHandshake()
|
|
}
|
|
|
|
device.state.stopping.Add(2)
|
|
go device.RoutineReadFromTUN()
|
|
go device.RoutineTUNEventReader()
|
|
|
|
return device
|
|
}
|
|
|
|
func (device *Device) LookupPeer(pk NoisePublicKey) *Peer {
|
|
device.peers.RLock()
|
|
defer device.peers.RUnlock()
|
|
|
|
return device.peers.keyMap[pk]
|
|
}
|
|
|
|
func (device *Device) RemovePeer(key NoisePublicKey) {
|
|
device.peers.Lock()
|
|
defer device.peers.Unlock()
|
|
// stop peer and remove from routing
|
|
|
|
peer, ok := device.peers.keyMap[key]
|
|
if ok {
|
|
unsafeRemovePeer(device, peer, key)
|
|
}
|
|
}
|
|
|
|
func (device *Device) RemoveAllPeers() {
|
|
device.peers.Lock()
|
|
defer device.peers.Unlock()
|
|
|
|
for key, peer := range device.peers.keyMap {
|
|
unsafeRemovePeer(device, peer, key)
|
|
}
|
|
|
|
device.peers.keyMap = make(map[NoisePublicKey]*Peer)
|
|
}
|
|
|
|
func (device *Device) FlushPacketQueues() {
|
|
for {
|
|
select {
|
|
case elem := <-device.queue.handshake:
|
|
device.PutMessageBuffer(elem.buffer)
|
|
default:
|
|
return
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
func (device *Device) Close() {
|
|
if device.isClosed.Swap(true) {
|
|
return
|
|
}
|
|
|
|
device.log.Verbosef("Device closing")
|
|
device.state.changing.Set(true)
|
|
device.state.Lock()
|
|
defer device.state.Unlock()
|
|
|
|
device.tun.device.Close()
|
|
device.BindClose()
|
|
|
|
device.isUp.Set(false)
|
|
|
|
// We kept a reference to the encryption and decryption queues,
|
|
// in case we started any new peers that might write to them.
|
|
// No new peers are coming; we are done with these queues.
|
|
device.queue.encryption.wg.Done()
|
|
device.queue.decryption.wg.Done()
|
|
close(device.signals.stop)
|
|
device.state.stopping.Wait()
|
|
|
|
device.RemoveAllPeers()
|
|
|
|
device.FlushPacketQueues()
|
|
|
|
device.rate.limiter.Close()
|
|
|
|
device.state.changing.Set(false)
|
|
device.log.Verbosef("Interface closed")
|
|
}
|
|
|
|
func (device *Device) Wait() chan struct{} {
|
|
return device.signals.stop
|
|
}
|
|
|
|
func (device *Device) SendKeepalivesToPeersWithCurrentKeypair() {
|
|
if device.isClosed.Get() {
|
|
return
|
|
}
|
|
|
|
device.peers.RLock()
|
|
for _, peer := range device.peers.keyMap {
|
|
peer.keypairs.RLock()
|
|
sendKeepalive := peer.keypairs.current != nil && !peer.keypairs.current.created.Add(RejectAfterTime).Before(time.Now())
|
|
peer.keypairs.RUnlock()
|
|
if sendKeepalive {
|
|
peer.SendKeepalive()
|
|
}
|
|
}
|
|
device.peers.RUnlock()
|
|
}
|
|
|
|
func unsafeCloseBind(device *Device) error {
|
|
var err error
|
|
netc := &device.net
|
|
if netc.netlinkCancel != nil {
|
|
netc.netlinkCancel.Cancel()
|
|
}
|
|
if netc.bind != nil {
|
|
err = netc.bind.Close()
|
|
netc.bind = nil
|
|
}
|
|
netc.stopping.Wait()
|
|
return err
|
|
}
|
|
|
|
func (device *Device) Bind() conn.Bind {
|
|
device.net.Lock()
|
|
defer device.net.Unlock()
|
|
return device.net.bind
|
|
}
|
|
|
|
func (device *Device) BindSetMark(mark uint32) error {
|
|
|
|
device.net.Lock()
|
|
defer device.net.Unlock()
|
|
|
|
// check if modified
|
|
|
|
if device.net.fwmark == mark {
|
|
return nil
|
|
}
|
|
|
|
// update fwmark on existing bind
|
|
|
|
device.net.fwmark = mark
|
|
if device.isUp.Get() && device.net.bind != nil {
|
|
if err := device.net.bind.SetMark(mark); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
// clear cached source addresses
|
|
|
|
device.peers.RLock()
|
|
for _, peer := range device.peers.keyMap {
|
|
peer.Lock()
|
|
defer peer.Unlock()
|
|
if peer.endpoint != nil {
|
|
peer.endpoint.ClearSrc()
|
|
}
|
|
}
|
|
device.peers.RUnlock()
|
|
|
|
return nil
|
|
}
|
|
|
|
func (device *Device) BindUpdate() error {
|
|
|
|
device.net.Lock()
|
|
defer device.net.Unlock()
|
|
|
|
// close existing sockets
|
|
|
|
if err := unsafeCloseBind(device); err != nil {
|
|
return err
|
|
}
|
|
|
|
// open new sockets
|
|
|
|
if device.isUp.Get() {
|
|
|
|
// bind to new port
|
|
|
|
var err error
|
|
netc := &device.net
|
|
netc.bind, netc.port, err = conn.CreateBind(netc.port)
|
|
if err != nil {
|
|
netc.bind = nil
|
|
netc.port = 0
|
|
return err
|
|
}
|
|
netc.netlinkCancel, err = device.startRouteListener(netc.bind)
|
|
if err != nil {
|
|
netc.bind.Close()
|
|
netc.bind = nil
|
|
netc.port = 0
|
|
return err
|
|
}
|
|
|
|
// set fwmark
|
|
|
|
if netc.fwmark != 0 {
|
|
err = netc.bind.SetMark(netc.fwmark)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
// clear cached source addresses
|
|
|
|
device.peers.RLock()
|
|
for _, peer := range device.peers.keyMap {
|
|
peer.Lock()
|
|
defer peer.Unlock()
|
|
if peer.endpoint != nil {
|
|
peer.endpoint.ClearSrc()
|
|
}
|
|
}
|
|
device.peers.RUnlock()
|
|
|
|
// start receiving routines
|
|
|
|
device.net.stopping.Add(2)
|
|
device.queue.decryption.wg.Add(2) // each RoutineReceiveIncoming goroutine writes to device.queue.decryption
|
|
go device.RoutineReceiveIncoming(ipv4.Version, netc.bind)
|
|
go device.RoutineReceiveIncoming(ipv6.Version, netc.bind)
|
|
|
|
device.log.Verbosef("UDP bind has been updated")
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (device *Device) BindClose() error {
|
|
device.net.Lock()
|
|
err := unsafeCloseBind(device)
|
|
device.net.Unlock()
|
|
return err
|
|
}
|