lzc256
/
tailscale
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

wgengine/router{win}: ignore broadcast routes added by Windows when removing routes. 

Signed-off-by: Maisem Ali <maisem@tailscale.com>
pull/1793/head
Maisem Ali 2021-04-23 21:23:59 -07:00 committed by Maisem Ali
parent f6b7d08aea
commit 590792915a
4 changed files with 123 additions and 63 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

106
wgengine/router/ifconfig_windows.go
View File

@ -713,22 +713,68 @@ func getInterfaceRoutes(ifc *winipcfg.IPAdapterAddresses, family winipcfg.Addres
return
}
// isSingleRouteInPrefixes reports whether r is a single-address
// prefix that appears in pfxs.
func isSingleRouteInPrefixes(r net.IPNet, pfxs []netaddr.IPPrefix) bool {
rr, ok := netaddr.FromStdIPNet(&r)
if !ok {
return false
func getAllInterfaceRoutes(ifc *winipcfg.IPAdapterAddresses) ([]*winipcfg.RouteData, error) {
routes4, err := getInterfaceRoutes(ifc, windows.AF_INET)
if err != nil {
return nil, err
}
if !rr.IsSingleIP() {
return false
routes6, err := getInterfaceRoutes(ifc, windows.AF_INET6)
if err != nil {
// TODO: what if v6 unavailable?
return nil, err
}
for _, pfx := range pfxs {
if pfx == rr {
return true
rd := make([]*winipcfg.RouteData, 0, len(routes4)+len(routes6))
for _, r := range routes4 {
rd = append(rd, &winipcfg.RouteData{
Destination: r.DestinationPrefix.IPNet(),
NextHop: r.NextHop.IP(),
Metric: r.Metric,
})
}
for _, r := range routes6 {
rd = append(rd, &winipcfg.RouteData{
Destination: r.DestinationPrefix.IPNet(),
NextHop: r.NextHop.IP(),
Metric: r.Metric,
})
}
return rd, nil
}
// filterRoutes removes routes that have been added by Windows and should not
// be managed by us.
func filterRoutes(routes []*winipcfg.RouteData, dontDelete []netaddr.IPPrefix) []*winipcfg.RouteData {
ddm := make(map[netaddr.IPPrefix]bool)
for _, dd := range dontDelete {
// See issue 1448: we don't want to touch the routes added
// by Windows for our interface addresses.
ddm[dd] = true
}
for _, r := range routes {
// We don't want to touch broadcast routes that Windows adds.
nr, ok := netaddr.FromStdIPNet(&r.Destination)
if !ok {
continue
}
if nr.IsSingleIP() {
continue
}
lastIP := nr.Range().To
ddm[netaddr.IPPrefix{
IP: lastIP,
Bits: lastIP.BitLen(),
}] = true
}
return false
filtered := make([]*winipcfg.RouteData, 0, len(routes))
for _, r := range routes {
rr, ok := netaddr.FromStdIPNet(&r.Destination)
if ok && ddm[rr] {
continue
}
filtered = append(filtered, r)
}
return filtered
}
// syncRoutes incrementally sets multiples routes on an interface.
@ -736,42 +782,11 @@ func isSingleRouteInPrefixes(r net.IPNet, pfxs []netaddr.IPPrefix) bool {
// dontDelete is a list of interface address routes that the
// synchronization logic should never delete.
func syncRoutes(ifc *winipcfg.IPAdapterAddresses, want []*winipcfg.RouteData, dontDelete []netaddr.IPPrefix) error {
routes4, err := getInterfaceRoutes(ifc, windows.AF_INET)
existingRoutes, err := getAllInterfaceRoutes(ifc)
if err != nil {
return err
}
routes6, err := getInterfaceRoutes(ifc, windows.AF_INET6)
if err != nil {
// TODO: what if v6 unavailable?
return err
}
got := make([]*winipcfg.RouteData, 0, len(routes4))
for _, r := range routes4 {
if isSingleRouteInPrefixes(r.DestinationPrefix.IPNet(), dontDelete) {
// See issue 1448: we don't want to touch the routes added
// by Windows for our interface addresses.
continue
}
got = append(got, &winipcfg.RouteData{
Destination: r.DestinationPrefix.IPNet(),
NextHop: r.NextHop.IP(),
Metric: r.Metric,
})
}
for _, r := range routes6 {
if isSingleRouteInPrefixes(r.DestinationPrefix.IPNet(), dontDelete) {
// See issue 1448: we don't want to touch the routes added
// by Windows for our interface addresses.
continue
}
got = append(got, &winipcfg.RouteData{
Destination: r.DestinationPrefix.IPNet(),
NextHop: r.NextHop.IP(),
Metric: r.Metric,
})
}
got := filterRoutes(existingRoutes, dontDelete)
add, del := deltaRouteData(got, want)
@ -783,6 +798,7 @@ func syncRoutes(ifc *winipcfg.IPAdapterAddresses, want []*winipcfg.RouteData, do
if dstStr == "169.254.255.255/32" {
// Issue 785. Ignore these routes
// failing to delete. Harmless.
// TODO(maisem): do we still need this?
continue
}
errs = append(errs, fmt.Errorf("deleting route %v: %w", dstStr, err))

49
wgengine/router/ifconfig_windows_test.go
View File

@ -193,6 +193,14 @@ func TestDeltaNets(t *testing.T) {
}
}
func formatRouteData(rds []*winipcfg.RouteData) string {
var b strings.Builder
for _, rd := range rds {
b.WriteString(fmt.Sprintf("%+v", rd))
}
return b.String()
}
func equalRouteDatas(a, b []*winipcfg.RouteData) bool {
if len(a) != len(b) {
return false
@ -205,6 +213,43 @@ func equalRouteDatas(a, b []*winipcfg.RouteData) bool {
return true
}
func TestFilterRoutes(t *testing.T) {
var h0 net.IP
in := []*winipcfg.RouteData{
// LinkLocal and Loopback routes.
{*ipnet4("169.254.0.0", 16), h0, 1},
{*ipnet4("169.254.255.255", 32), h0, 1},
{*ipnet4("127.0.0.0", 8), h0, 1},
{*ipnet4("127.255.255.255", 32), h0, 1},
// Local LAN routes.
{*ipnet4("192.168.0.0", 24), h0, 1},
{*ipnet4("192.168.0.255", 32), h0, 1},
{*ipnet4("192.168.1.0", 25), h0, 1},
{*ipnet4("192.168.1.127", 32), h0, 1},
// Some random other route.
{*ipnet4("192.168.2.23", 32), h0, 1},
// Our own tailscale address.
{*ipnet4("100.100.100.100", 32), h0, 1},
// Other tailscale addresses.
{*ipnet4("100.100.100.101", 32), h0, 1},
{*ipnet4("100.100.100.102", 32), h0, 1},
}
want := []*winipcfg.RouteData{
{*ipnet4("169.254.0.0", 16), h0, 1},
{*ipnet4("127.0.0.0", 8), h0, 1},
{*ipnet4("192.168.0.0", 24), h0, 1},
{*ipnet4("192.168.1.0", 25), h0, 1},
{*ipnet4("192.168.2.23", 32), h0, 1},
{*ipnet4("100.100.100.101", 32), h0, 1},
{*ipnet4("100.100.100.102", 32), h0, 1},
}
got := filterRoutes(in, mustCIDRs("100.100.100.100/32"))
if !equalRouteDatas(got, want) {
t.Errorf("\ngot: %v\n want: %v\n", formatRouteData(got), formatRouteData(want))
}
}
func TestDeltaRouteData(t *testing.T) {
var h0 net.IP
h1 := net.ParseIP("99.99.99.99")
@ -232,9 +277,9 @@ func TestDeltaRouteData(t *testing.T) {
}
if !equalRouteDatas(add, wantAdd) {
t.Errorf("add:\n got: %v\n want: %v\n", add, wantAdd)
t.Errorf("add:\n got: %v\n want: %v\n", formatRouteData(add), formatRouteData(wantAdd))
}
if !equalRouteDatas(del, wantDel) {
t.Errorf("del:\n got: %v\n want: %v\n", del, wantDel)
t.Errorf("del:\n got: %v\n want: %v\n", formatRouteData(del), formatRouteData(wantDel))
}
}

16
wgengine/router/router_linux_test.go
View File

@ -20,22 +20,6 @@ import (
"inet.af/netaddr"
)
func mustCIDR(s string) netaddr.IPPrefix {
pfx, err := netaddr.ParseIPPrefix(s)
if err != nil {
panic(err)
}
return pfx
}
func mustCIDRs(ss ...string) []netaddr.IPPrefix {
var ret []netaddr.IPPrefix
for _, s := range ss {
ret = append(ret, mustCIDR(s))
}
return ret
}
func TestRouterStates(t *testing.T) {
basic := `
ip rule add -4 pref 5210 fwmark 0x80000 table main

15
wgengine/router/router_test.go 100644
View File

@ -0,0 +1,15 @@
// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package router
import "inet.af/netaddr"
func mustCIDRs(ss ...string) []netaddr.IPPrefix {
var ret []netaddr.IPPrefix
for _, s := range ss {
ret = append(ret, netaddr.MustParseIPPrefix(s))
}
return ret
}