cmd/tailscale: fix another up warning with exit nodes

The --advertise-routes and --advertise-exit-node flags both mutating
one pref is the gift that keeps on giving.

I need to rewrite the this up warning code to first map prefs back to
flag values and then just compare flags instead of comparing prefs,
but this is the minimal fix for now.

This also includes work on the tests, to make them easier to write
(and more accurate), by letting you write the flag args directly and
have that parse into the upArgs/MaskedPrefs directly, the same as the
code, rather than them being possibly out of sync being written by
hand.

Fixes https://twitter.com/EXPbits/status/1390418145047887877

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit e78e26b6fb)
This commit is contained in:
Brad Fitzpatrick 2021-05-06 15:27:02 -07:00
parent e7899afbf6
commit ff4c2dbec9
2 changed files with 124 additions and 147 deletions

View File

@ -39,47 +39,41 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
}
tests := []struct {
name string
// flags, if non-nil populates flagSet and mp.
flags []string // if non-nil,
// flagSet and mp are required if flags is nil.
// flagSet is the set of flags that were explicitly set in flags.
// mp is the mutation to apply to server.
flagSet map[string]bool
mp *ipn.MaskedPrefs
curPrefs *ipn.Prefs
curUser string // os.Getenv("USER") on the client side
goos string // empty means "linux"
mp *ipn.MaskedPrefs
want string
}{
{
name: "bare_up_means_up",
flagSet: f(),
flags: []string{},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
WantRunning: false,
Hostname: "foo",
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
WantRunning: true,
},
WantRunningSet: true,
},
want: "",
},
{
name: "losing_hostname",
flagSet: f("accept-dns"),
flags: []string{"--accept-dns"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
WantRunning: false,
Hostname: "foo",
CorpDNS: true,
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
WantRunning: true,
CorpDNS: true,
},
ControlURLSet: true,
WantRunningSet: true,
CorpDNSSet: true,
NetfilterMode: preftype.NetfilterOn,
AllowSingleHosts: true,
},
want: accidentalUpPrefix + " --accept-dns --hostname=foo",
},
@ -185,46 +179,34 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
},
{
name: "error_advertised_routes_exit_node_removed",
flagSet: f("advertise-routes"),
flags: []string{"--advertise-routes=10.0.42.0/24"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("10.0.42.0/24"),
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
},
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("10.0.42.0/24"),
},
},
AdvertiseRoutesSet: true,
},
want: accidentalUpPrefix + " --advertise-routes=10.0.42.0/24 --advertise-exit-node",
},
{
name: "advertised_routes_exit_node_removed",
flagSet: f("advertise-routes", "advertise-exit-node"),
flags: []string{"--advertise-routes=10.0.42.0/24", "--advertise-exit-node=false"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("10.0.42.0/24"),
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
},
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("10.0.42.0/24"),
},
},
AdvertiseRoutesSet: true,
},
want: "",
},
{
@ -251,92 +233,45 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
},
want: "",
},
{
name: "advertised_routes_includes_only_one_0_route", // and no --advertise-exit-node
flagSet: f("advertise-routes"),
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("10.0.42.0/24"),
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
},
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("11.1.43.0/24"),
netaddr.MustParseIPPrefix("0.0.0.0/0"),
},
},
AdvertiseRoutesSet: true,
},
want: accidentalUpPrefix + " --advertise-routes=11.1.43.0/24,0.0.0.0/0 --advertise-exit-node",
},
{
name: "advertise_exit_node", // Issue 1859
flagSet: f("advertise-exit-node"),
flags: []string{"--advertise-exit-node"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
},
},
// Note: without setting "AdvertiseRoutesSet", as
// updateMaskedPrefsFromUpFlag doesn't set that.
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
},
want: "",
},
{
name: "advertise_exit_node_over_existing_routes",
flagSet: f("advertise-exit-node"),
flags: []string{"--advertise-exit-node"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("1.2.0.0/16"),
},
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
},
},
// Note: without setting "AdvertiseRoutesSet", as
// updateMaskedPrefsFromUpFlag doesn't set that.
},
want: accidentalUpPrefix + " --advertise-exit-node --advertise-routes=1.2.0.0/16",
},
{
name: "advertise_exit_node_over_existing_routes_and_exit_node",
flagSet: f("advertise-exit-node"),
flags: []string{"--advertise-exit-node"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
netaddr.MustParseIPPrefix("1.2.0.0/16"),
},
},
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
},
},
// Note: without setting "AdvertiseRoutesSet", as
// updateMaskedPrefsFromUpFlag doesn't set that.
},
want: accidentalUpPrefix + " --advertise-exit-node --advertise-routes=1.2.0.0/16",
},
{
@ -357,14 +292,14 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
},
{
name: "remove_all_implicit",
flagSet: f("force-reauth"),
flags: []string{"--force-reauth"},
curPrefs: &ipn.Prefs{
WantRunning: true,
ControlURL: ipn.DefaultControlURL,
RouteAll: true,
AllowSingleHosts: false,
ExitNodeIP: netaddr.MustParseIP("100.64.5.6"),
CorpDNS: true,
CorpDNS: false,
ShieldsUp: true,
AdvertiseTags: []string{"tag:foo", "tag:bar"},
Hostname: "myhostname",
@ -376,24 +311,18 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
OperatorUser: "alice",
},
curUser: "eve",
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
WantRunning: true,
},
},
want: accidentalUpPrefix + " --force-reauth --accept-routes --exit-node=100.64.5.6 --accept-dns --shields-up --advertise-tags=tag:foo,tag:bar --hostname=myhostname --unattended --advertise-routes=10.0.0.0/16 --netfilter-mode=nodivert --operator=alice",
want: accidentalUpPrefix + " --force-reauth --accept-routes --host-routes=false --exit-node=100.64.5.6 --accept-dns=false --shields-up --advertise-tags=tag:foo,tag:bar --hostname=myhostname --unattended --advertise-routes=10.0.0.0/16 --netfilter-mode=nodivert --operator=alice",
},
{
name: "remove_all_implicit_except_hostname",
flagSet: f("hostname"),
flags: []string{"--hostname=newhostname"},
curPrefs: &ipn.Prefs{
WantRunning: true,
ControlURL: ipn.DefaultControlURL,
RouteAll: true,
AllowSingleHosts: false,
ExitNodeIP: netaddr.MustParseIP("100.64.5.6"),
CorpDNS: true,
CorpDNS: false,
ShieldsUp: true,
AdvertiseTags: []string{"tag:foo", "tag:bar"},
Hostname: "myhostname",
@ -405,15 +334,7 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
OperatorUser: "alice",
},
curUser: "eve",
mp: &ipn.MaskedPrefs{
Prefs: ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
WantRunning: true,
Hostname: "newhostname",
},
HostnameSet: true,
},
want: accidentalUpPrefix + " --hostname=newhostname --accept-routes --exit-node=100.64.5.6 --accept-dns --shields-up --advertise-tags=tag:foo,tag:bar --unattended --advertise-routes=10.0.0.0/16 --netfilter-mode=nodivert --operator=alice",
want: accidentalUpPrefix + " --hostname=newhostname --accept-routes --host-routes=false --exit-node=100.64.5.6 --accept-dns=false --shields-up --advertise-tags=tag:foo,tag:bar --unattended --advertise-routes=10.0.0.0/16 --netfilter-mode=nodivert --operator=alice",
},
{
name: "loggedout_is_implicit",
@ -472,6 +393,38 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
},
want: "", // not an error
},
{
name: "operator_losing_routes_step1", // https://twitter.com/EXPbits/status/1390418145047887877
flags: []string{"--operator=expbits"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
netaddr.MustParseIPPrefix("1.2.0.0/16"),
},
},
want: accidentalUpPrefix + " --operator=expbits --advertise-routes=1.2.0.0/16 --advertise-exit-node",
},
{
name: "operator_losing_routes_step2", // https://twitter.com/EXPbits/status/1390418145047887877
flags: []string{"--operator=expbits", "--advertise-routes=1.2.0.0/16"},
curPrefs: &ipn.Prefs{
ControlURL: ipn.DefaultControlURL,
AllowSingleHosts: true,
CorpDNS: true,
NetfilterMode: preftype.NetfilterOn,
AdvertiseRoutes: []netaddr.IPPrefix{
netaddr.MustParseIPPrefix("0.0.0.0/0"),
netaddr.MustParseIPPrefix("::/0"),
netaddr.MustParseIPPrefix("1.2.0.0/16"),
},
},
want: accidentalUpPrefix + " --advertise-routes=1.2.0.0/16 --operator=expbits --advertise-exit-node",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
@ -479,8 +432,23 @@ func TestCheckForAccidentalSettingReverts(t *testing.T) {
if tt.goos != "" {
goos = tt.goos
}
flagSet := tt.flagSet
mp := tt.mp
if tt.flags != nil {
if tt.flagSet != nil || tt.mp != nil {
t.Fatal("flags and flagSet/mp are mutually exclusive")
}
var upArgs upArgsT
fs := newUpFlagSet(goos, &upArgs)
fs.Parse(tt.flags)
prefs, err := prefsFromUpArgs(upArgs, t.Logf, new(ipnstate.Status), goos)
if err != nil {
t.Fatal(err)
}
flagSet, mp = flagSetAndMaskedPrefs(prefs, fs)
}
var got string
if err := checkForAccidentalSettingReverts(tt.flagSet, tt.curPrefs, tt.mp, goos, tt.curUser); err != nil {
if err := checkForAccidentalSettingReverts(flagSet, tt.curPrefs, mp, goos, tt.curUser); err != nil {
got = err.Error()
}
if strings.TrimSpace(got) != tt.want {

View File

@ -295,14 +295,7 @@ func runUp(ctx context.Context, args []string) error {
return err
}
flagSet := map[string]bool{}
mp := new(ipn.MaskedPrefs)
mp.WantRunningSet = true
mp.Prefs = *prefs
upFlagSet.Visit(func(f *flag.Flag) {
updateMaskedPrefsFromUpFlag(mp, f.Name)
flagSet[f.Name] = true
})
flagSet, mp := flagSetAndMaskedPrefs(prefs, upFlagSet)
if !upArgs.reset {
if err := checkForAccidentalSettingReverts(flagSet, curPrefs, mp, runtime.GOOS, os.Getenv("USER")); err != nil {
@ -498,6 +491,18 @@ func addPrefFlagMapping(flagName string, prefNames ...string) {
}
}
func flagSetAndMaskedPrefs(prefs *ipn.Prefs, fs *flag.FlagSet) (flagSetMap map[string]bool, mp *ipn.MaskedPrefs) {
flagSetMap = map[string]bool{}
mp = new(ipn.MaskedPrefs)
mp.WantRunningSet = true
mp.Prefs = *prefs
fs.Visit(func(f *flag.Flag) {
updateMaskedPrefsFromUpFlag(mp, f.Name)
flagSetMap[f.Name] = true
})
return flagSetMap, mp
}
func updateMaskedPrefsFromUpFlag(mp *ipn.MaskedPrefs, flagName string) {
if prefs, ok := prefsOfFlag[flagName]; ok {
for _, pref := range prefs {
@ -635,8 +640,12 @@ func checkForAccidentalSettingReverts(flagSet map[string]bool, curPrefs *ipn.Pre
missing = append(missing, fmtFlagValueArg("exit-node", fmtSettingVal(exi)))
}
case "advertise-routes":
hadExitNode := hasExitNodeRoutes(exi.([]netaddr.IPPrefix))
routes := withoutExitNodes(exi.([]netaddr.IPPrefix))
missing = append(missing, fmtFlagValueArg("advertise-routes", fmtSettingVal(routes)))
if hadExitNode && !flagSet["advertise-exit-node"] {
missing = append(missing, "--advertise-exit-node")
}
default:
missing = append(missing, fmtFlagValueArg(flagName, fmtSettingVal(exi)))
}