tailscale/util/syspolicy/source/json_policy_store_test.go
Brad Fitzpatrick b6e17df646 cmd/tailscaled, util/syspolicy: add JSON syspolicy file support
Tailscaled had no way to seed device-scope syspolicy settings short of
environment variables or a custom store wired up out of tree. Add a
--syspolicy-file flag whose default points at a well-known JSON file
that, when present, is parsed as a map[string]any and registered as a
device-scope policy source. The default path is
/etc/tailscale/syspolicy.json on every non-Windows platform (Linux, the
BSDs, illumos/Solaris, and tailscaled-without-the-GUI on macOS) and
%ProgramData%\Tailscale\syspolicy.json on Windows. The flag lets users
running tailscaled by hand (development, custom installs) point it at
an alternate file, and "" disables the load entirely.

JSON values map to setting types as expected: strings to
StringValue/PreferenceOptionValue/VisibilityValue/DurationValue (e.g.
"24h" parsed by time.ParseDuration), booleans to BooleanValue, numbers
to IntegerValue, and string arrays to StringListValue. The file is
validated against the registered setting definitions at load time so
unknown keys and value/type mismatches fail startup loudly rather than
producing surprising defaults at first read.

When HuJSON support is linked into the build (default; opt out with
ts_omit_hujsonconf), the file may use HuJSON (comments, trailing
commas). With ts_omit_hujsonconf it must be pure standard JSON. This
mirrors the pattern used by ipn/conffile.

On Windows the JSON file and the existing HKLM registry store both
register at DeviceScope. rsop merges later-registered same-scope
sources over earlier ones, so per-key values in the file override the
registry while keys absent from the file fall back to the registry.

The loader is registered via a feature.Hook from a file gated by
!ts_omit_syspolicy, and called from main after flag parsing. tsnet
still does not depend on the root syspolicy package, so embedders
don't pick this up implicitly.

Fixes #20305

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Change-Id: Ie6326461c14efb226979ac162998a9c6373ce493
2026-06-30 13:10:16 -07:00

367 lines
11 KiB
Go

// Copyright (c) Tailscale Inc & contributors
// SPDX-License-Identifier: BSD-3-Clause
package source
import (
"errors"
"os"
"path/filepath"
"reflect"
"strings"
"testing"
"time"
"tailscale.com/util/syspolicy/pkey"
"tailscale.com/util/syspolicy/ptype"
"tailscale.com/util/syspolicy/setting"
)
func TestJSONPolicyStoreReadString(t *testing.T) {
s := NewJSONPolicyStore(map[string]any{
"ControlURL": "https://controlplane.example.com",
"AuthKey": "tskey-auth-xxx",
"Bool": true,
})
got, err := s.ReadString("ControlURL")
if err != nil {
t.Fatalf("ReadString(ControlURL) error: %v", err)
}
if want := "https://controlplane.example.com"; got != want {
t.Errorf("ReadString(ControlURL) = %q, want %q", got, want)
}
if _, err := s.ReadString("Missing"); !errors.Is(err, setting.ErrNotConfigured) {
t.Errorf("ReadString(Missing) err = %v, want ErrNotConfigured", err)
}
if _, err := s.ReadString("Bool"); !errors.Is(err, setting.ErrTypeMismatch) {
t.Errorf("ReadString(Bool) err = %v, want ErrTypeMismatch", err)
}
}
func TestJSONPolicyStoreReadBoolean(t *testing.T) {
s := NewJSONPolicyStore(map[string]any{
"AlwaysOn": true,
"Str": "yes",
})
got, err := s.ReadBoolean("AlwaysOn")
if err != nil {
t.Fatalf("ReadBoolean(AlwaysOn) error: %v", err)
}
if !got {
t.Errorf("ReadBoolean(AlwaysOn) = false, want true")
}
if _, err := s.ReadBoolean("Missing"); !errors.Is(err, setting.ErrNotConfigured) {
t.Errorf("ReadBoolean(Missing) err = %v, want ErrNotConfigured", err)
}
if _, err := s.ReadBoolean("Str"); !errors.Is(err, setting.ErrTypeMismatch) {
t.Errorf("ReadBoolean(Str) err = %v, want ErrTypeMismatch", err)
}
}
func TestJSONPolicyStoreReadStringArray(t *testing.T) {
s := NewJSONPolicyStore(map[string]any{
"AllowedSuggestedExitNodes": []any{"node-a", "node-b"},
"Empty": []any{},
"NotArray": "abc",
"WrongElem": []any{"a", 1},
})
got, err := s.ReadStringArray("AllowedSuggestedExitNodes")
if err != nil {
t.Fatalf("ReadStringArray(AllowedSuggestedExitNodes) error: %v", err)
}
if want := []string{"node-a", "node-b"}; !reflect.DeepEqual(got, want) {
t.Errorf("ReadStringArray = %v, want %v", got, want)
}
got, err = s.ReadStringArray("Empty")
if err != nil {
t.Fatalf("ReadStringArray(Empty) error: %v", err)
}
if len(got) != 0 {
t.Errorf("ReadStringArray(Empty) = %v, want empty", got)
}
if _, err := s.ReadStringArray("Missing"); !errors.Is(err, setting.ErrNotConfigured) {
t.Errorf("ReadStringArray(Missing) err = %v, want ErrNotConfigured", err)
}
if _, err := s.ReadStringArray("NotArray"); !errors.Is(err, setting.ErrTypeMismatch) {
t.Errorf("ReadStringArray(NotArray) err = %v, want ErrTypeMismatch", err)
}
if _, err := s.ReadStringArray("WrongElem"); !errors.Is(err, setting.ErrTypeMismatch) {
t.Errorf("ReadStringArray(WrongElem) err = %v, want ErrTypeMismatch", err)
}
}
func TestJSONPolicyStoreReadUInt64FromMap(t *testing.T) {
s := NewJSONPolicyStore(map[string]any{
"Float": float64(42),
"Negative": float64(-1),
"Frac": float64(1.5),
"Str": "nope",
})
got, err := s.ReadUInt64("Float")
if err != nil {
t.Fatalf("ReadUInt64(Float) error: %v", err)
}
if got != 42 {
t.Errorf("ReadUInt64(Float) = %d, want 42", got)
}
if _, err := s.ReadUInt64("Missing"); !errors.Is(err, setting.ErrNotConfigured) {
t.Errorf("ReadUInt64(Missing) err = %v, want ErrNotConfigured", err)
}
for _, k := range []pkey.Key{"Negative", "Frac", "Str"} {
if _, err := s.ReadUInt64(k); !errors.Is(err, setting.ErrTypeMismatch) {
t.Errorf("ReadUInt64(%s) err = %v, want ErrTypeMismatch", k, err)
}
}
}
func TestJSONPolicyStoreReadUInt64FromJSON(t *testing.T) {
// json.Number path: bigger than float64 mantissa precision.
s, err := NewJSONPolicyStoreFromBytes([]byte(`{"Big": 18446744073709551610}`))
if err != nil {
t.Fatalf("NewJSONPolicyStoreFromBytes: %v", err)
}
got, err := s.ReadUInt64("Big")
if err != nil {
t.Fatalf("ReadUInt64(Big) error: %v", err)
}
if want := uint64(18446744073709551610); got != want {
t.Errorf("ReadUInt64(Big) = %d, want %d", got, want)
}
}
// TestJSONPolicyStoreDuration verifies that duration-typed settings, which
// the reader fetches via ReadString and parses with time.ParseDuration, work
// end-to-end with values like "24h".
func TestJSONPolicyStoreDuration(t *testing.T) {
s := NewJSONPolicyStore(map[string]any{
"ReconnectAfter": "24h",
"Bad": "notaduration",
})
def := setting.NewDefinition("ReconnectAfter", setting.DeviceSetting, setting.DurationValue)
v, err := readPolicySettingValue(s, def)
if err != nil {
t.Fatalf("readPolicySettingValue(ReconnectAfter) error: %v", err)
}
if got, want := v.(time.Duration), 24*time.Hour; got != want {
t.Errorf("ReconnectAfter = %v, want %v", got, want)
}
badDef := setting.NewDefinition("Bad", setting.DeviceSetting, setting.DurationValue)
if _, err := readPolicySettingValue(s, badDef); err == nil {
t.Errorf("readPolicySettingValue(Bad) err = nil, want parse error")
}
}
func TestJSONPolicyStorePreferenceOptionAndVisibility(t *testing.T) {
s := NewJSONPolicyStore(map[string]any{
"CheckUpdates": "always",
"AdminConsoleVisibility": "hide",
})
prefDef := setting.NewDefinition("CheckUpdates", setting.DeviceSetting, setting.PreferenceOptionValue)
v, err := readPolicySettingValue(s, prefDef)
if err != nil {
t.Fatalf("readPolicySettingValue(CheckUpdates) error: %v", err)
}
if got := v.(ptype.PreferenceOption); got != ptype.AlwaysByPolicy {
t.Errorf("CheckUpdates = %v, want AlwaysByPolicy", got)
}
visDef := setting.NewDefinition("AdminConsoleVisibility", setting.UserSetting, setting.VisibilityValue)
v, err = readPolicySettingValue(s, visDef)
if err != nil {
t.Fatalf("readPolicySettingValue(AdminConsoleVisibility) error: %v", err)
}
if got := v.(ptype.Visibility); got != ptype.HiddenByPolicy {
t.Errorf("AdminConsoleVisibility = %v, want HiddenByPolicy", got)
}
}
func TestJSONPolicyStoreValidate(t *testing.T) {
// Register a small set of definitions covering each type that the
// validator needs to exercise.
if err := setting.SetDefinitionsForTest(t,
setting.NewDefinition("ControlURL", setting.DeviceSetting, setting.StringValue),
setting.NewDefinition("AlwaysOn", setting.DeviceSetting, setting.BooleanValue),
setting.NewDefinition("AllowedSuggestedExitNodes", setting.DeviceSetting, setting.StringListValue),
setting.NewDefinition("ReconnectAfter", setting.DeviceSetting, setting.DurationValue),
setting.NewDefinition("CheckUpdates", setting.DeviceSetting, setting.PreferenceOptionValue),
setting.NewDefinition("AdminConsoleVisibility", setting.UserSetting, setting.VisibilityValue),
); err != nil {
t.Fatal(err)
}
tests := []struct {
name string
json map[string]any
wantOK bool
wantErrSubs []string // substrings the error must contain (only when wantOK is false)
}{
{
name: "empty",
json: map[string]any{},
wantOK: true,
},
{
name: "all_valid",
json: map[string]any{
"ControlURL": "https://controlplane.example.com",
"AlwaysOn": true,
"AllowedSuggestedExitNodes": []any{"node-a", "node-b"},
"ReconnectAfter": "24h",
"CheckUpdates": "always",
"AdminConsoleVisibility": "hide",
},
wantOK: true,
},
{
name: "unknown_key",
json: map[string]any{
"ControlURL": "https://controlplane.example.com",
"NoSuchThing": "whatever",
},
wantErrSubs: []string{`unknown policy setting "NoSuchThing"`},
},
{
name: "wrong_type_string",
json: map[string]any{
"ControlURL": true,
},
wantErrSubs: []string{`"ControlURL"`, "type mismatch"},
},
{
name: "wrong_type_bool",
json: map[string]any{
"AlwaysOn": "yes",
},
wantErrSubs: []string{`"AlwaysOn"`, "type mismatch"},
},
{
name: "wrong_type_array",
json: map[string]any{
"AllowedSuggestedExitNodes": "node-a",
},
wantErrSubs: []string{`"AllowedSuggestedExitNodes"`, "type mismatch"},
},
{
name: "bad_duration",
json: map[string]any{
"ReconnectAfter": "notaduration",
},
wantErrSubs: []string{`"ReconnectAfter"`, "notaduration"},
},
{
name: "bad_preference_option",
json: map[string]any{
"CheckUpdates": "sometimes",
},
wantErrSubs: []string{`"CheckUpdates"`, "sometimes", "always"},
},
{
name: "bad_visibility",
json: map[string]any{
"AdminConsoleVisibility": "maybe",
},
wantErrSubs: []string{`"AdminConsoleVisibility"`, "maybe", "show"},
},
{
name: "multiple_errors_reported",
json: map[string]any{
"AlwaysOn": "yes",
"NoSuchThing": 1,
},
wantErrSubs: []string{`"AlwaysOn"`, `unknown policy setting "NoSuchThing"`},
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
err := NewJSONPolicyStore(tt.json).Validate()
if tt.wantOK {
if err != nil {
t.Fatalf("Validate() = %v, want nil", err)
}
return
}
if err == nil {
t.Fatalf("Validate() = nil, want error containing %v", tt.wantErrSubs)
}
for _, sub := range tt.wantErrSubs {
if !strings.Contains(err.Error(), sub) {
t.Errorf("Validate() error = %q, want it to contain %q", err, sub)
}
}
})
}
}
func TestNewJSONPolicyStoreFromBytesHuJSON(t *testing.T) {
if hujsonStandardize == nil {
t.Skip("HuJSON support not linked into this build")
}
const hujsonInput = `{
// The control plane URL.
"ControlURL": "https://controlplane.example.com",
"AlwaysOn": true, // trailing comma is OK in HuJSON
}`
s, err := NewJSONPolicyStoreFromBytes([]byte(hujsonInput))
if err != nil {
t.Fatalf("NewJSONPolicyStoreFromBytes(HuJSON) error: %v", err)
}
got, err := s.ReadString("ControlURL")
if err != nil {
t.Fatalf("ReadString: %v", err)
}
if want := "https://controlplane.example.com"; got != want {
t.Errorf("ReadString = %q, want %q", got, want)
}
gotBool, err := s.ReadBoolean("AlwaysOn")
if err != nil {
t.Fatalf("ReadBoolean: %v", err)
}
if !gotBool {
t.Errorf("ReadBoolean = false, want true")
}
}
func TestNewJSONPolicyStoreFromFile(t *testing.T) {
dir := t.TempDir()
path := filepath.Join(dir, "syspolicy.json")
if err := os.WriteFile(path, []byte(`{"ControlURL": "https://example.com"}`), 0600); err != nil {
t.Fatal(err)
}
s, err := NewJSONPolicyStoreFromFile(path)
if err != nil {
t.Fatalf("NewJSONPolicyStoreFromFile: %v", err)
}
got, err := s.ReadString("ControlURL")
if err != nil {
t.Fatalf("ReadString: %v", err)
}
if want := "https://example.com"; got != want {
t.Errorf("ReadString = %q, want %q", got, want)
}
if _, err := NewJSONPolicyStoreFromFile(filepath.Join(dir, "missing.json")); err == nil {
t.Errorf("NewJSONPolicyStoreFromFile(missing) err = nil, want error")
}
bad := filepath.Join(dir, "bad.json")
if err := os.WriteFile(bad, []byte(`not json`), 0600); err != nil {
t.Fatal(err)
}
if _, err := NewJSONPolicyStoreFromFile(bad); err == nil {
t.Errorf("NewJSONPolicyStoreFromFile(bad) err = nil, want parse error")
}
}