Replace registry-access code, update wireguard-go and x/sys/windows.

Signed-off-by: Aleksandar Pesic <peske.nis@gmail.com>

go.mod

@@ -23,15 +23,15 @@ require (
 	github.com/pborman/getopt v0.0.0-20190409184431-ee0cd42419d3
 	github.com/peterbourgon/ff/v2 v2.0.0
 	github.com/tailscale/depaware v0.0.0-20201003033024-5d95aab075be
-	github.com/tailscale/wireguard-go v0.0.0-20201204174856-4a319d8d5bfb
+	github.com/tailscale/wireguard-go v0.0.0-20201210001956-32a957fb6709
 	github.com/tcnksm/go-httpstat v0.2.0
 	github.com/toqueteos/webbrowser v1.2.0
 	go4.org/mem v0.0.0-20201119185036-c04c5a6ff174
-	golang.org/x/crypto v0.0.0-20201112155050-0c6587e931a9
+	golang.org/x/crypto v0.0.0-20201124201722-c8d3bf9c5392
 	golang.org/x/net v0.0.0-20201110031124-69a78807bb2b
 	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d
 	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208
-	golang.org/x/sys v0.0.0-20201202213521-69691e467435
+	golang.org/x/sys v0.0.0-20201210223839-7e3030f88018
 	golang.org/x/term v0.0.0-20201207232118-ee85cb95a76b
 	golang.org/x/time v0.0.0-20191024005414-555d28b269f0
 	golang.org/x/tools v0.0.0-20201002184944-ecd9fd270d5d

go.sum

@@ -116,6 +116,9 @@ github.com/tailscale/wireguard-go v0.0.0-20201021041318-a6168fd06b3f h1:KMx58dbn
 github.com/tailscale/wireguard-go v0.0.0-20201021041318-a6168fd06b3f/go.mod h1:WXq+IkSOJGIgfF1XW+4z4oW+LX/TXzU9DcKlT5EZLi4=
 github.com/tailscale/wireguard-go v0.0.0-20201204174856-4a319d8d5bfb h1:lPrU+j3X85IpVF8saRAAnhER6/RmtpV9mSZFx/rQXJc=
 github.com/tailscale/wireguard-go v0.0.0-20201204174856-4a319d8d5bfb/go.mod h1:RMjerRBNxOIkYHMFnxMWLFYngXD6zexR/v5Dn4a5Zcc=
+github.com/tailscale/wireguard-go v0.0.0-20201210001956-32a957fb6709 h1:cxiYxd+Kb+LuXBpv6rp2CpWGhhcVB5b07B6h+kA7LP4=
+github.com/tailscale/wireguard-go v0.0.0-20201210001956-32a957fb6709/go.mod h1:9PbAnF5CAklkURoO0uQhm+YUjDmm9T9oCyTGlCHuTPQ=
+github.com/tailscale/wireguard-go v0.0.20201118 h1:gtjCCz7el67M8M3BmOLlsaTBnWqVJ3uH7Z8+uO1fjeI=
 github.com/tcnksm/go-httpstat v0.2.0 h1:rP7T5e5U2HfmOBmZzGgGZjBQ5/GluWUylujl0tJ04I0=
 github.com/tcnksm/go-httpstat v0.2.0/go.mod h1:s3JVJFtQxtBEBC9dwcdTTXS9xFnM3SXAZwPG41aurT8=
 github.com/toqueteos/webbrowser v1.2.0 h1:tVP/gpK69Fx+qMJKsLE7TD8LuGWPnEV71wBN9rrstGQ=
@@ -141,6 +144,8 @@ golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20201016220609-9e8e0b390897/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20201112155050-0c6587e931a9 h1:umElSU9WZirRdgu2yFHY0ayQkEnKiOC1TtM3fWXFnoU=
 golang.org/x/crypto v0.0.0-20201112155050-0c6587e931a9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20201124201722-c8d3bf9c5392 h1:xYJJ3S178yv++9zXV/hnr29plCAGO9vAFG9dorqaFQc=
+golang.org/x/crypto v0.0.0-20201124201722-c8d3bf9c5392/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
 golang.org/x/mod v0.3.0 h1:RM4zey1++hCTbCVQfnWeKs9/IEsaBLA8vTkd0WVtmH4=
@@ -182,6 +187,7 @@ golang.org/x/sys v0.0.0-20190904154756-749cb33beabd/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191003212358-c178f38b412c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191008105621-543471e840be/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200501145240-bc7a7d42d5c3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -196,6 +202,9 @@ golang.org/x/sys v0.0.0-20201112073958-5cba982894dd/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201202213521-69691e467435 h1:25AvDqqB9PrNqj1FLf2/70I4W0L19qqoaFq3gjNwbKk=
 golang.org/x/sys v0.0.0-20201202213521-69691e467435/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201210223839-7e3030f88018 h1:XKi8B/gRBuTZN1vU9gFsLMm6zVz5FSCDzm8JYACnjy8=
+golang.org/x/sys v0.0.0-20201210223839-7e3030f88018/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
 golang.org/x/term v0.0.0-20201207232118-ee85cb95a76b h1:a0ErnNnPKmhDyIXQvdZr+Lq8dc8xpMeqkF8y5PgQU4Q=
 golang.org/x/term v0.0.0-20201207232118-ee85cb95a76b/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

wgengine/router/dns/manager_windows.go

@@ -7,12 +7,13 @@
 import (
 	"fmt"
 	"os/exec"
+	"runtime"
 	"strings"
 	"syscall"
 	"time"
 
 	"github.com/tailscale/wireguard-go/tun"
-	wgregistry "github.com/tailscale/wireguard-go/tun/wintun/registry"
+	"golang.org/x/sys/windows"
 	"golang.org/x/sys/windows/registry"
 	"tailscale.com/types/logger"
 )
@@ -35,14 +36,76 @@ func newManager(mconfig ManagerConfig) managerImpl {
 	}
 }
 
-// keyOpenTimeout is how long we wait for a registry key to
+const (
-// appear. For some reason, registry keys tied to ephemeral interfaces
+	// keyOpenTimeout is how long we wait for a registry key to
-// can take a long while to appear after interface creation, and we
+	// appear. For some reason, registry keys tied to ephemeral interfaces
-// can end up racing with that.
+	// can take a long while to appear after interface creation, and we
-const keyOpenTimeout = time.Minute
+	// can end up racing with that.
+	keyOpenTimeout = time.Minute
+
+	// REG_NOTIFY_CHANGE_NAME notifies the caller if a subkey is added or deleted.
+	REG_NOTIFY_CHANGE_NAME uint32 = 0x00000001
+)
+
+func openKeyWait(k registry.Key, path string, access uint32, timeout time.Duration) (registry.Key, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	deadline := time.Now().Add(timeout)
+	pathSpl := strings.Split(path, "\\")
+	for i := 0; ; i++ {
+		keyName := pathSpl[i]
+		isLast := i+1 == len(pathSpl)
+
+		event, err := windows.CreateEvent(nil, 0, 0, nil)
+		if err != nil {
+			return 0, fmt.Errorf("windows.CreateEvent: %v", err)
+		}
+		defer windows.CloseHandle(event)
+
+		var key registry.Key
+		for {
+			err = windows.RegNotifyChangeKeyValue(windows.Handle(k), false, REG_NOTIFY_CHANGE_NAME, event, true)
+			if err != nil {
+				return 0, fmt.Errorf("windows.RegNotifyChangeKeyValue: %v", err)
+			}
+
+			var accessFlags uint32
+			if isLast {
+				accessFlags = access
+			} else {
+				accessFlags = registry.NOTIFY
+			}
+			key, err = registry.OpenKey(k, keyName, accessFlags)
+			if err == windows.ERROR_FILE_NOT_FOUND || err == windows.ERROR_PATH_NOT_FOUND {
+				timeout := time.Until(deadline) / time.Millisecond
+				if timeout < 0 {
+					timeout = 0
+				}
+				s, err := windows.WaitForSingleObject(event, uint32(timeout))
+				if err != nil {
+					return 0, fmt.Errorf("windows.WaitForSingleObject: %v", err)
+				}
+				if s == uint32(windows.WAIT_TIMEOUT) { // windows.WAIT_TIMEOUT status const is misclassified as error in golang.org/x/sys/windows
+					return 0, fmt.Errorf("timeout waiting for registry key")
+				}
+			} else if err != nil {
+				return 0, fmt.Errorf("registry.OpenKey(%v): %v", path, err)
+			} else {
+				if isLast {
+					return key, nil
+				}
+				defer key.Close()
+				break
+			}
+		}
+
+		k = key
+	}
+}
 
 func setRegistryString(path, name, value string) error {
-	key, err := wgregistry.OpenKeyWait(registry.LOCAL_MACHINE, path, registry.SET_VALUE, keyOpenTimeout)
+	key, err := openKeyWait(registry.LOCAL_MACHINE, path, registry.SET_VALUE, keyOpenTimeout)
 	if err != nil {
 		return fmt.Errorf("opening %s: %w", path, err)
 	}