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control/controlknobs, all: add plumbed Knobs type, not global variables

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Previously two tsnet nodes in the same process couldn't have disjoint
sets of controlknob settings from control as both would overwrite each
other's global variables.

This plumbs a new controlknobs.Knobs type around everywhere and hangs
the knobs sent by control on that instead.

Updates #9351

Change-Id: I75338646d36813ed971b4ffad6f9a8b41ec91560
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This commit is contained in:
Brad Fitzpatrick 2023-09-11 12:03:39 -07:00 committed by Brad Fitzpatrick
parent d050700a3b
commit 4e91cf20a8
19 changed files with 136 additions and 100 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
cmd/tailscale/cli/netcheck.go
View File

@ -53,7 +53,7 @@ func runNetcheck(ctx context.Context, args []string) error {
return err
}
c := &netcheck.Client{
PortMapper: portmapper.NewClient(logf, netMon, nil, nil),
PortMapper: portmapper.NewClient(logf, netMon, nil, nil, nil),
UseDNSCache: false, // always resolve, don't cache
}
if netcheckArgs.verbose {

1
cmd/tailscaled/tailscaled.go
View File

@ -607,6 +607,7 @@ func tryEngine(logf logger.Logf, sys *tsd.System, name string) (onlyNetstack boo
NetMon: sys.NetMon.Get(),
Dialer: sys.Dialer.Get(),
SetSubsystem: sys.Set,
ControlKnobs: sys.ControlKnobs(),
}
onlyNetstack = name == "userspace-networking"

1
cmd/tsconnect/wasm/wasm_js.go
View File

@ -102,6 +102,7 @@ func newIPN(jsConfig js.Value) map[string]any {
eng, err := wgengine.NewUserspaceEngine(logf, wgengine.Config{
Dialer: dialer,
SetSubsystem: sys.Set,
ControlKnobs: sys.ControlKnobs(),
})
if err != nil {
log.Fatal(err)

59
control/controlclient/direct.go
View File

@ -25,7 +25,6 @@
"slices"
"strings"
"sync"
"sync/atomic"
"time"
"go4.org/mem"
@ -44,7 +43,6 @@
"tailscale.com/net/tsdial"
"tailscale.com/net/tshttpproxy"
"tailscale.com/smallzstd"
"tailscale.com/syncs"
"tailscale.com/tailcfg"
"tailscale.com/tka"
"tailscale.com/tstime"
@ -66,7 +64,8 @@ type Direct struct {
httpc *http.Client // HTTP client used to talk to tailcontrol
dialer *tsdial.Dialer
dnsCache *dnscache.Resolver
serverURL string // URL of the tailcontrol server
controlKnobs *controlknobs.Knobs // always non-nil
serverURL string // URL of the tailcontrol server
clock tstime.Clock
lastPrintMap time.Time
logf logger.Logf
@ -129,6 +128,7 @@ type Options struct {
OnControlTime func(time.Time) // optional func to notify callers of new time from control
Dialer *tsdial.Dialer // non-nil
C2NHandler http.Handler // or nil
ControlKnobs *controlknobs.Knobs // or nil to ignore
// Observer is called when there's a change in status to report
// from the control client.
@ -202,6 +202,9 @@ func NewDirect(opts Options) (*Direct, error) {
if opts.GetMachinePrivateKey == nil {
return nil, errors.New("controlclient.New: no GetMachinePrivateKey specified")
}
if opts.ControlKnobs == nil {
opts.ControlKnobs = &controlknobs.Knobs{}
}
opts.ServerURL = strings.TrimRight(opts.ServerURL, "/")
serverURL, err := url.Parse(opts.ServerURL)
if err != nil {
@ -249,6 +252,7 @@ func NewDirect(opts Options) (*Direct, error) {
c := &Direct{
httpc: httpc,
controlKnobs: opts.ControlKnobs,
getMachinePrivKey: opts.GetMachinePrivateKey,
serverURL: opts.ServerURL,
clock: opts.Clock,
@ -946,7 +950,7 @@ func (c *Direct) sendMapRequest(ctx context.Context, isStreaming bool, nu Netmap
var mapResIdx int // 0 for first message, then 1+ for deltas
sess := newMapSession(persist.PrivateNodeKey(), nu)
sess := newMapSession(persist.PrivateNodeKey(), nu, c.controlKnobs)
defer sess.Close()
sess.cancel = cancel
sess.logf = c.logf
@ -1287,38 +1291,11 @@ func initDevKnob() devKnobs {
var clock tstime.Clock = tstime.StdClock{}
// config from control.
var (
controlDisableDRPO atomic.Bool
controlKeepFullWGConfig atomic.Bool
controlRandomizeClientPort atomic.Bool
controlOneCGNAT syncs.AtomicValue[opt.Bool]
)
// DisableDRPO reports whether control says to disable the
// DERP route optimization (Issue 150).
func DisableDRPO() bool {
return controlDisableDRPO.Load()
}
// KeepFullWGConfig reports whether control says we should disable the lazy
// wireguard programming and instead give it the full netmap always.
func KeepFullWGConfig() bool {
return controlKeepFullWGConfig.Load()
}
// RandomizeClientPort reports whether control says we should randomize
// the client port.
func RandomizeClientPort() bool {
return controlRandomizeClientPort.Load()
}
// ControlOneCGNATSetting returns control's OneCGNAT setting, if any.
func ControlOneCGNATSetting() opt.Bool {
return controlOneCGNAT.Load()
}
func setControlKnobsFromNodeAttrs(selfNodeAttrs []string) {
func (ms *mapSession) setControlKnobsFromNodeAttrs(selfNodeAttrs []string) {
k := ms.controlKnobs
if k == nil {
return
}
var (
keepFullWG bool
disableDRPO bool
@ -1342,11 +1319,11 @@ func setControlKnobsFromNodeAttrs(selfNodeAttrs []string) {
oneCGNAT.Set(false)
}
}
controlKeepFullWGConfig.Store(keepFullWG)
controlDisableDRPO.Store(disableDRPO)
controlknobs.SetDisableUPnP(disableUPnP)
controlRandomizeClientPort.Store(randomizeClientPort)
controlOneCGNAT.Store(oneCGNAT)
k.KeepFullWGConfig.Store(keepFullWG)
k.DisableDRPO.Store(disableDRPO)
k.DisableUPnP.Store(disableUPnP)
k.RandomizeClientPort.Store(randomizeClientPort)
k.OneCGNAT.Store(oneCGNAT)
}
// ipForwardingBroken reports whether the system's IP forwarding is disabled

9
control/controlclient/map.go
View File

@ -15,6 +15,7 @@
"strconv"
"sync"
"tailscale.com/control/controlknobs"
"tailscale.com/envknob"
"tailscale.com/tailcfg"
"tailscale.com/tstime"
@ -38,7 +39,8 @@
// one MapRequest).
type mapSession struct {
// Immutable fields.
nu NetmapUpdater // called on changes (in addition to the optional hooks below)
nu NetmapUpdater // called on changes (in addition to the optional hooks below)
controlKnobs *controlknobs.Knobs // or nil
privateNodeKey key.NodePrivate
publicNodeKey key.NodePublic
logf logger.Logf
@ -94,9 +96,10 @@ type mapSession struct {
// Modify its optional fields on the returned value before use.
//
// It must have its Close method called to release resources.
func newMapSession(privateNodeKey key.NodePrivate, nu NetmapUpdater) *mapSession {
func newMapSession(privateNodeKey key.NodePrivate, nu NetmapUpdater, controlKnobs *controlknobs.Knobs) *mapSession {
ms := &mapSession{
nu: nu,
controlKnobs: controlKnobs,
privateNodeKey: privateNodeKey,
publicNodeKey: privateNodeKey.Public(),
lastDNSConfig: new(tailcfg.DNSConfig),
@ -184,7 +187,7 @@ func (ms *mapSession) HandleNonKeepAliveMapResponse(ctx context.Context, resp *t
if DevKnob.StripCaps() {
resp.Node.Capabilities = nil
}
setControlKnobsFromNodeAttrs(resp.Node.Capabilities)
ms.setControlKnobsFromNodeAttrs(resp.Node.Capabilities)
}
// Call Node.InitDisplayNames on any changed nodes.

3
control/controlclient/map_test.go
View File

@ -16,6 +16,7 @@
"github.com/google/go-cmp/cmp"
"go4.org/mem"
"tailscale.com/control/controlknobs"
"tailscale.com/tailcfg"
"tailscale.com/tstest"
"tailscale.com/tstime"
@ -392,7 +393,7 @@ func formatNodes(nodes []*tailcfg.Node) string {
}
func newTestMapSession(t testing.TB, nu NetmapUpdater) *mapSession {
ms := newMapSession(key.NewNode(), nu)
ms := newMapSession(key.NewNode(), nu, new(controlknobs.Knobs))
t.Cleanup(ms.Close)
ms.logf = t.Logf
return ms

36
control/controlknobs/controlknobs.go
View File

@ -8,22 +8,30 @@
import (
"sync/atomic"
"tailscale.com/envknob"
"tailscale.com/syncs"
"tailscale.com/types/opt"
)
// disableUPnP indicates whether to attempt UPnP mapping.
var disableUPnPControl atomic.Bool
// Knobs is the set of knobs that the control plane's coordination server can
// adjust at runtime.
type Knobs struct {
// DisableUPnP indicates whether to attempt UPnP mapping.
DisableUPnP atomic.Bool
var disableUPnpEnv = envknob.RegisterBool("TS_DISABLE_UPNP")
// DisableDRPO is whether control says to disable the
// DERP route optimization (Issue 150).
DisableDRPO atomic.Bool
// DisableUPnP reports the last reported value from control
// whether UPnP portmapping should be disabled.
func DisableUPnP() bool {
return disableUPnPControl.Load() || disableUPnpEnv()
}
// SetDisableUPnP sets whether control says that UPnP should be
// disabled.
func SetDisableUPnP(v bool) {
disableUPnPControl.Store(v)
// KeepFullWGConfig is whether we should disable the lazy wireguard
// programming and instead give WireGuard the full netmap always, even for
// idle peers.
KeepFullWGConfig atomic.Bool
// RandomizeClientPort is whether control says we should randomize
// the client port.
RandomizeClientPort atomic.Bool
// OneCGNAT is whether the the node should make one big CGNAT route
// in the OS rather than one /32 per peer.
OneCGNAT syncs.AtomicValue[opt.Bool]
}

20
ipn/ipnlocal/local.go
View File

@ -34,6 +34,7 @@
"gvisor.dev/gvisor/pkg/tcpip"
"tailscale.com/client/tailscale/apitype"
"tailscale.com/control/controlclient"
"tailscale.com/control/controlknobs"
"tailscale.com/doctor"
"tailscale.com/doctor/permissions"
"tailscale.com/doctor/routetable"
@ -3084,7 +3085,7 @@ func (b *LocalBackend) authReconfig() {
return
}
oneCGNATRoute := shouldUseOneCGNATRoute(b.logf, version.OS())
oneCGNATRoute := shouldUseOneCGNATRoute(b.logf, b.sys.ControlKnobs(), version.OS())
rcfg := b.routerConfig(cfg, prefs, oneCGNATRoute)
dcfg := dnsConfigForNetmap(nm, prefs, b.logf, version.OS())
@ -3102,11 +3103,13 @@ func (b *LocalBackend) authReconfig() {
//
// The versionOS is a Tailscale-style version ("iOS", "macOS") and not
// a runtime.GOOS.
func shouldUseOneCGNATRoute(logf logger.Logf, versionOS string) bool {
// Explicit enabling or disabling always take precedence.
if v, ok := controlclient.ControlOneCGNATSetting().Get(); ok {
logf("[v1] shouldUseOneCGNATRoute: explicit=%v", v)
return v
func shouldUseOneCGNATRoute(logf logger.Logf, controlKnobs *controlknobs.Knobs, versionOS string) bool {
if controlKnobs != nil {
// Explicit enabling or disabling always take precedence.
if v, ok := controlKnobs.OneCGNAT.Load().Get(); ok {
logf("[v1] shouldUseOneCGNATRoute: explicit=%v", v)
return v
}
}
// Also prefer to do this on the Mac, so that we don't need to constantly
@ -4663,6 +4666,11 @@ func (b *LocalBackend) DebugReSTUN() error {
return nil
}
// ControlKnobs returns the node's control knobs.
func (b *LocalBackend) ControlKnobs() *controlknobs.Knobs {
return b.sys.ControlKnobs()
}
func (b *LocalBackend) magicConn() (*magicsock.Conn, error) {
mc, ok := b.sys.MagicSock.GetOK()
if !ok {

2
ipn/localapi/localapi.go
View File

@ -694,7 +694,7 @@ func (h *Handler) serveDebugPortmap(w http.ResponseWriter, r *http.Request) {
done := make(chan bool, 1)
var c *portmapper.Client
c = portmapper.NewClient(logger.WithPrefix(logf, "portmapper: "), h.netMon, debugKnobs, func() {
c = portmapper.NewClient(logger.WithPrefix(logf, "portmapper: "), h.netMon, debugKnobs, h.b.ControlKnobs(), func() {
logf("portmapping changed.")
logf("have mapping: %v", c.HaveMapping())

3
net/portmapper/igd_test.go
View File

@ -14,6 +14,7 @@
"sync/atomic"
"testing"
"tailscale.com/control/controlknobs"
"tailscale.com/net/netaddr"
"tailscale.com/types/logger"
)
@ -249,7 +250,7 @@ func (d *TestIGD) handlePCPQuery(pkt []byte, src netip.AddrPort) {
func newTestClient(t *testing.T, igd *TestIGD) *Client {
var c *Client
c = NewClient(t.Logf, nil, nil, func() {
c = NewClient(t.Logf, nil, nil, new(controlknobs.Knobs), func() {
t.Logf("port map changed")
t.Logf("have mapping: %v", c.HaveMapping())
})

14
net/portmapper/portmapper.go
View File

@ -18,6 +18,7 @@
"time"
"go4.org/mem"
"tailscale.com/control/controlknobs"
"tailscale.com/net/interfaces"
"tailscale.com/net/netaddr"
"tailscale.com/net/neterror"
@ -66,6 +67,7 @@ type DebugKnobs struct {
type Client struct {
logf logger.Logf
netMon *netmon.Monitor // optional; nil means interfaces will be looked up on-demand
controlKnobs *controlknobs.Knobs
ipAndGateway func() (gw, ip netip.Addr, ok bool)
onChange func() // or nil
debug DebugKnobs
@ -166,15 +168,19 @@ func (m *pmpMapping) Release(ctx context.Context) {
// The debug argument allows configuring the behaviour of the portmapper for
// debugging; if nil, a sensible set of defaults will be used.
//
// The optional onChange argument specifies a func to run in a new
// goroutine whenever the port mapping status has changed. If nil,
// it doesn't make a callback.
func NewClient(logf logger.Logf, netMon *netmon.Monitor, debug *DebugKnobs, onChange func()) *Client {
// The controlKnobs, if non-nil, specifies the control knobs from the control
// plane that might disable portmapping.
//
// The optional onChange argument specifies a func to run in a new goroutine
// whenever the port mapping status has changed. If nil, it doesn't make a
// callback.
func NewClient(logf logger.Logf, netMon *netmon.Monitor, debug *DebugKnobs, controlKnobs *controlknobs.Knobs, onChange func()) *Client {
ret := &Client{
logf: logf,
netMon: netMon,
ipAndGateway: interfaces.LikelyHomeRouterIP,
onChange: onChange,
controlKnobs: controlKnobs,
}
if debug != nil {
ret.debug = *debug

8
net/portmapper/portmapper_test.go
View File

@ -10,13 +10,15 @@
"strconv"
"testing"
"time"
"tailscale.com/control/controlknobs"
)
func TestCreateOrGetMapping(t *testing.T) {
if v, _ := strconv.ParseBool(os.Getenv("HIT_NETWORK")); !v {
t.Skip("skipping test without HIT_NETWORK=1")
}
c := NewClient(t.Logf, nil, nil, nil)
c := NewClient(t.Logf, nil, nil, new(controlknobs.Knobs), nil)
defer c.Close()
c.SetLocalPort(1234)
for i := 0; i < 2; i++ {
@ -32,7 +34,7 @@ func TestClientProbe(t *testing.T) {
if v, _ := strconv.ParseBool(os.Getenv("HIT_NETWORK")); !v {
t.Skip("skipping test without HIT_NETWORK=1")
}
c := NewClient(t.Logf, nil, nil, nil)
c := NewClient(t.Logf, nil, nil, new(controlknobs.Knobs), nil)
defer c.Close()
for i := 0; i < 3; i++ {
if i > 0 {
@ -47,7 +49,7 @@ func TestClientProbeThenMap(t *testing.T) {
if v, _ := strconv.ParseBool(os.Getenv("HIT_NETWORK")); !v {
t.Skip("skipping test without HIT_NETWORK=1")
}
c := NewClient(t.Logf, nil, nil, nil)
c := NewClient(t.Logf, nil, nil, new(controlknobs.Knobs), nil)
defer c.Close()
c.SetLocalPort(1234)
res, err := c.Probe(context.Background())

10
net/portmapper/upnp.go
View File

@ -24,7 +24,7 @@
"github.com/tailscale/goupnp"
"github.com/tailscale/goupnp/dcps/internetgateway2"
"tailscale.com/control/controlknobs"
"tailscale.com/envknob"
"tailscale.com/net/netns"
"tailscale.com/types/logger"
)
@ -192,7 +192,7 @@ func addAnyPortMapping(
// The provided ctx is not retained in the returned upnpClient, but
// its associated HTTP client is (if set via goupnp.WithHTTPClient).
func getUPnPClient(ctx context.Context, logf logger.Logf, debug DebugKnobs, gw netip.Addr, meta uPnPDiscoResponse) (client upnpClient, err error) {
if controlknobs.DisableUPnP() || debug.DisableUPnP {
if debug.DisableUPnP {
return nil, nil
}
@ -270,6 +270,10 @@ func (c *Client) upnpHTTPClientLocked() *http.Client {
return c.uPnPHTTPClient
}
var (
disableUPnpEnv = envknob.RegisterBool("TS_DISABLE_UPNP")
)
// getUPnPPortMapping attempts to create a port-mapping over the UPnP protocol. On success,
// it will return the externally exposed IP and port. Otherwise, it will return a zeroed IP and
// port and an error.
@ -279,7 +283,7 @@ func (c *Client) getUPnPPortMapping(
internal netip.AddrPort,
prevPort uint16,
) (external netip.AddrPort, ok bool) {
if controlknobs.DisableUPnP() || c.debug.DisableUPnP {
if disableUPnpEnv() || c.debug.DisableUPnP || (c.controlKnobs != nil && c.controlKnobs.DisableUPnP.Load()) {
return netip.AddrPort{}, false
}

7
tsd/tsd.go
View File

@ -21,6 +21,7 @@
"fmt"
"reflect"
"tailscale.com/control/controlknobs"
"tailscale.com/ipn"
"tailscale.com/net/dns"
"tailscale.com/net/netmon"
@ -42,6 +43,7 @@ type System struct {
Router SubSystem[router.Router]
Tun SubSystem[*tstun.Wrapper]
StateStore SubSystem[ipn.StateStore]
controlKnobs controlknobs.Knobs
}
// Set is a convenience method to set a subsystem value.
@ -85,6 +87,11 @@ func (s *System) IsNetstack() bool {
return name == tstun.FakeTUNName
}
// ControlKnobs returns the control knobs for this node.
func (s *System) ControlKnobs() *controlknobs.Knobs {
return &s.controlKnobs
}
// SubSystem represents some subsystem of the Tailscale node daemon.
//
// A subsystem can be set to a value, and then later retrieved. A subsystem

1
tsnet/tsnet.go
View File

@ -501,6 +501,7 @@ func (s *Server) start() (reterr error) {
NetMon: s.netMon,
Dialer: s.dialer,
SetSubsystem: sys.Set,
ControlKnobs: sys.ControlKnobs(),
})
if err != nil {
return err

7
wgengine/magicsock/derp.go
View File

@ -18,7 +18,6 @@
"time"
"github.com/tailscale/wireguard-go/conn"
"tailscale.com/control/controlclient"
"tailscale.com/derp"
"tailscale.com/derp/derphttp"
"tailscale.com/health"
@ -38,11 +37,11 @@
//
// By default it's enabled, unless an environment variable
// or control says to disable it.
func useDerpRoute() bool {
func (c *Conn) useDerpRoute() bool {
if b, ok := debugUseDerpRoute().Get(); ok {
return b
}
return !controlclient.DisableDRPO()
return c.controlKnobs == nil || !c.controlKnobs.DisableDRPO.Load()
}
// derpRoute is a route entry for a public key, saying that a certain
@ -294,7 +293,7 @@ func (c *Conn) derpWriteChanOfAddr(addr netip.AddrPort, peer key.NodePublic) cha
// perhaps peer's home is Frankfurt, but they dialed our home DERP
// node in SF to reach us, so we can reply to them using our
// SF connection rather than dialing Frankfurt. (Issue 150)
if !peer.IsZero() && useDerpRoute() {
if !peer.IsZero() && c.useDerpRoute() {
if r, ok := c.derpRoute[peer]; ok {
if ad, ok := c.activeDerp[r.derpID]; ok && ad.c == r.dc {
c.setPeerLastDerpLocked(peer, r.derpID, regionID)

9
wgengine/magicsock/magicsock.go
View File

@ -25,6 +25,7 @@
"golang.org/x/net/ipv4"
"golang.org/x/net/ipv6"
"tailscale.com/control/controlknobs"
"tailscale.com/disco"
"tailscale.com/envknob"
"tailscale.com/health"
@ -87,6 +88,7 @@ type Conn struct {
testOnlyPacketListener nettype.PacketListener
noteRecvActivity func(key.NodePublic) // or nil, see Options.NoteRecvActivity
netMon *netmon.Monitor // or nil
controlKnobs *controlknobs.Knobs // or nil
// ================================================================
// No locking required to access these fields, either because
@ -340,6 +342,10 @@ type Options struct {
// NetMon is the network monitor to use.
// With one, the portmapper won't be used.
NetMon *netmon.Monitor
// ControlKnobs are the set of control knobs to use.
// If nil, they're ignored and not updated.
ControlKnobs *controlknobs.Knobs
}
func (o *Options) logf() logger.Logf {
@ -400,13 +406,14 @@ func newConn() *Conn {
func NewConn(opts Options) (*Conn, error) {
c := newConn()
c.port.Store(uint32(opts.Port))
c.controlKnobs = opts.ControlKnobs
c.logf = opts.logf()
c.epFunc = opts.endpointsFunc()
c.derpActiveFunc = opts.derpActiveFunc()
c.idleFunc = opts.IdleFunc
c.testOnlyPacketListener = opts.TestOnlyPacketListener
c.noteRecvActivity = opts.NoteRecvActivity
c.portMapper = portmapper.NewClient(logger.WithPrefix(c.logf, "portmapper: "), opts.NetMon, nil, c.onPortMapChanged)
c.portMapper = portmapper.NewClient(logger.WithPrefix(c.logf, "portmapper: "), opts.NetMon, nil, opts.ControlKnobs, c.onPortMapChanged)
if opts.NetMon != nil {
c.portMapper.SetGatewayLookupFunc(opts.NetMon.GatewayAndSelfIP)
}

32
wgengine/userspace.go
View File

@ -19,7 +19,7 @@
"github.com/tailscale/wireguard-go/device"
"github.com/tailscale/wireguard-go/tun"
"tailscale.com/control/controlclient"
"tailscale.com/control/controlknobs"
"tailscale.com/envknob"
"tailscale.com/health"
"tailscale.com/ipn/ipnstate"
@ -95,9 +95,10 @@ type userspaceEngine struct {
dns *dns.Manager
magicConn *magicsock.Conn
netMon *netmon.Monitor
netMonOwned bool // whether we created netMon (and thus need to close it)
netMonUnregister func() // unsubscribes from changes; used regardless of netMonOwned
birdClient BIRDClient // or nil
netMonOwned bool // whether we created netMon (and thus need to close it)
netMonUnregister func() // unsubscribes from changes; used regardless of netMonOwned
birdClient BIRDClient // or nil
controlKnobs *controlknobs.Knobs // or nil
testMaybeReconfigHook func() // for tests; if non-nil, fires if maybeReconfigWireguardLocked called
@ -183,6 +184,11 @@ type Config struct {
// If nil, a new Dialer is created
Dialer *tsdial.Dialer
// ControlKnobs is the set of control plane-provied knobs
// to use.
// If nil, defaults are used.
ControlKnobs *controlknobs.Knobs
// ListenPort is the port on which the engine will listen.
// If zero, a port is automatically selected.
ListenPort uint16
@ -220,6 +226,8 @@ func NewFakeUserspaceEngine(logf logger.Logf, opts ...any) (Engine, error) {
conf.ListenPort = uint16(v)
case func(any):
conf.SetSubsystem = v
case *controlknobs.Knobs:
conf.ControlKnobs = v
default:
return nil, fmt.Errorf("unknown option type %T", v)
}
@ -271,6 +279,7 @@ func NewUserspaceEngine(logf logger.Logf, conf Config) (_ Engine, reterr error)
router: conf.Router,
confListenPort: conf.ListenPort,
birdClient: conf.BIRDClient,
controlKnobs: conf.ControlKnobs,
}
if e.birdClient != nil {
@ -326,6 +335,7 @@ func NewUserspaceEngine(logf logger.Logf, conf Config) (_ Engine, reterr error)
IdleFunc: e.tundev.IdleDuration,
NoteRecvActivity: e.noteRecvActivity,
NetMon: e.netMon,
ControlKnobs: conf.ControlKnobs,
}
var err error
@ -493,12 +503,12 @@ func (e *userspaceEngine) handleLocalPackets(p *packet.Parsed, t *tstun.Wrapper)
// That's sad too. Or we get rid of these knobs (lazy wireguard config has been
// stable!) but I'm worried that a future regression would be easier to debug
// with these knobs in place.
func forceFullWireguardConfig(numPeers int) bool {
func (e *userspaceEngine) forceFullWireguardConfig(numPeers int) bool {
// Did the user explicitly enable trimming via the environment variable knob?
if b, ok := debugTrimWireguard().Get(); ok {
return !b
}
return controlclient.KeepFullWGConfig()
return e.controlKnobs != nil && e.controlKnobs.KeepFullWGConfig.Load()
}
// isTrimmablePeer reports whether p is a peer that we can trim out of the
@ -508,8 +518,8 @@ func forceFullWireguardConfig(numPeers int) bool {
// only non-subnet AllowedIPs (an IPv4 /32 or IPv6 /128), which is the
// common case for most peers. Subnet router nodes will just always be
// created in the wireguard-go config.
func isTrimmablePeer(p *wgcfg.Peer, numPeers int) bool {
if forceFullWireguardConfig(numPeers) {
func (e *userspaceEngine) isTrimmablePeer(p *wgcfg.Peer, numPeers int) bool {
if e.forceFullWireguardConfig(numPeers) {
return false
}
@ -625,7 +635,7 @@ func (e *userspaceEngine) maybeReconfigWireguardLocked(discoChanged map[key.Node
for i := range full.Peers {
p := &full.Peers[i]
nk := p.PublicKey
if !isTrimmablePeer(p, len(full.Peers)) {
if !e.isTrimmablePeer(p, len(full.Peers)) {
min.Peers = append(min.Peers, *p)
if discoChanged[nk] {
needRemoveStep = true
@ -766,8 +776,6 @@ func hasOverlap(aips, rips views.Slice[netip.Prefix]) bool {
return false
}
var randomizeClientPort = controlclient.RandomizeClientPort
func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config, dnsCfg *dns.Config) error {
if routerCfg == nil {
panic("routerCfg must not be nil")
@ -794,7 +802,7 @@ func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config,
e.mu.Unlock()
listenPort := e.confListenPort
if randomizeClientPort() {
if e.controlKnobs != nil && e.controlKnobs.RandomizeClientPort.Load() {
listenPort = 0
}

12
wgengine/userspace_test.go
View File

@ -11,6 +11,7 @@
"go4.org/mem"
"tailscale.com/cmd/testwrapper/flakytest"
"tailscale.com/control/controlknobs"
"tailscale.com/net/dns"
"tailscale.com/net/netaddr"
"tailscale.com/net/tstun"
@ -152,15 +153,16 @@ func TestUserspaceEngineReconfig(t *testing.T) {
}
func TestUserspaceEnginePortReconfig(t *testing.T) {
tstest.Replace(t, &randomizeClientPort, func() bool { return false })
flakytest.Mark(t, "https://github.com/tailscale/tailscale/issues/2855")
const defaultPort = 49983
var knobs controlknobs.Knobs
// Keep making a wgengine until we find an unused port
var ue *userspaceEngine
for i := 0; i < 100; i++ {
attempt := uint16(defaultPort + i)
e, err := NewFakeUserspaceEngine(t.Logf, attempt)
e, err := NewFakeUserspaceEngine(t.Logf, attempt, &knobs)
if err != nil {
t.Fatal(err)
}
@ -199,7 +201,7 @@ func TestUserspaceEnginePortReconfig(t *testing.T) {
t.Errorf("no debug setting changed local port to %d from %d", got, startingPort)
}
randomizeClientPort = func() bool { return true }
knobs.RandomizeClientPort.Store(true)
if err := ue.Reconfig(cfg, routerCfg, &dns.Config{}); err != nil {
t.Fatal(err)
}
@ -208,7 +210,7 @@ func TestUserspaceEnginePortReconfig(t *testing.T) {
}
lastPort := ue.magicConn.LocalPort()
randomizeClientPort = func() bool { return false }
knobs.RandomizeClientPort.Store(false)
if err := ue.Reconfig(cfg, routerCfg, &dns.Config{}); err != nil {
t.Fatal(err)
}