tailscale/net/dns/manager_test.go
David Anderson 97d2fa2f56 net/dns: work around WSL DNS implementation flaws.
Fixes tailscale/corp#1662

Signed-off-by: David Anderson <danderson@tailscale.com>
2021-04-26 16:54:50 -07:00

446 lines
11 KiB
Go

// 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 dns
import (
"runtime"
"testing"
"github.com/google/go-cmp/cmp"
"github.com/google/go-cmp/cmp/cmpopts"
"inet.af/netaddr"
"tailscale.com/net/dns/resolver"
"tailscale.com/util/dnsname"
)
type fakeOSConfigurator struct {
SplitDNS bool
BaseConfig OSConfig
OSConfig OSConfig
ResolverConfig resolver.Config
}
func (c *fakeOSConfigurator) SetDNS(cfg OSConfig) error {
if !c.SplitDNS && len(cfg.MatchDomains) > 0 {
panic("split DNS config passed to non-split OSConfigurator")
}
c.OSConfig = cfg
return nil
}
func (c *fakeOSConfigurator) SetResolver(cfg resolver.Config) {
c.ResolverConfig = cfg
}
func (c *fakeOSConfigurator) SupportsSplitDNS() bool {
return c.SplitDNS
}
func (c *fakeOSConfigurator) GetBaseConfig() (OSConfig, error) {
return c.BaseConfig, nil
}
func (c *fakeOSConfigurator) Close() error { return nil }
func TestManager(t *testing.T) {
if runtime.GOOS == "windows" {
t.Skipf("test's assumptions break because of https://github.com/tailscale/corp/issues/1662")
}
// Note: these tests assume that it's safe to switch the
// OSConfigurator's split-dns support on and off between Set
// calls. Empirically this is currently true, because we reprobe
// the support every time we generate configs. It would be
// reasonable to make this unsupported as well, in which case
// these tests will need tweaking.
tests := []struct {
name string
in Config
split bool
bs OSConfig
os OSConfig
rs resolver.Config
}{
{
name: "empty",
},
{
name: "search-only",
in: Config{
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
os: OSConfig{
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
},
{
name: "corp",
in: Config{
DefaultResolvers: mustIPPs("1.1.1.1:53", "9.9.9.9:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
os: OSConfig{
Nameservers: mustIPs("1.1.1.1", "9.9.9.9"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
},
{
name: "corp-split",
in: Config{
DefaultResolvers: mustIPPs("1.1.1.1:53", "9.9.9.9:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("1.1.1.1", "9.9.9.9"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
},
{
name: "corp-magic",
in: Config{
DefaultResolvers: mustIPPs("1.1.1.1:53", "9.9.9.9:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
AuthoritativeSuffixes: fqdns("ts.com"),
},
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
rs: resolver.Config{
Routes: upstreams(".", "1.1.1.1:53", "9.9.9.9:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
LocalDomains: fqdns("ts.com."),
},
},
{
name: "corp-magic-split",
in: Config{
DefaultResolvers: mustIPPs("1.1.1.1:53", "9.9.9.9:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
AuthoritativeSuffixes: fqdns("ts.com"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
rs: resolver.Config{
Routes: upstreams(".", "1.1.1.1:53", "9.9.9.9:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
LocalDomains: fqdns("ts.com."),
},
},
{
name: "corp-routes",
in: Config{
DefaultResolvers: mustIPPs("1.1.1.1:53", "9.9.9.9:53"),
Routes: upstreams("corp.com", "2.2.2.2:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
rs: resolver.Config{
Routes: upstreams(
".", "1.1.1.1:53", "9.9.9.9:53",
"corp.com.", "2.2.2.2:53"),
},
},
{
name: "corp-routes-split",
in: Config{
DefaultResolvers: mustIPPs("1.1.1.1:53", "9.9.9.9:53"),
Routes: upstreams("corp.com", "2.2.2.2:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
rs: resolver.Config{
Routes: upstreams(
".", "1.1.1.1:53", "9.9.9.9:53",
"corp.com.", "2.2.2.2:53"),
},
},
{
name: "routes",
in: Config{
Routes: upstreams("corp.com", "2.2.2.2:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
bs: OSConfig{
Nameservers: mustIPs("8.8.8.8"),
SearchDomains: fqdns("coffee.shop"),
},
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf", "coffee.shop"),
},
rs: resolver.Config{
Routes: upstreams(
".", "8.8.8.8:53",
"corp.com.", "2.2.2.2:53"),
},
},
{
name: "routes-split",
in: Config{
Routes: upstreams("corp.com", "2.2.2.2:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("2.2.2.2"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
MatchDomains: fqdns("corp.com"),
},
},
{
name: "routes-multi",
in: Config{
Routes: upstreams(
"corp.com", "2.2.2.2:53",
"bigco.net", "3.3.3.3:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
bs: OSConfig{
Nameservers: mustIPs("8.8.8.8"),
SearchDomains: fqdns("coffee.shop"),
},
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf", "coffee.shop"),
},
rs: resolver.Config{
Routes: upstreams(
".", "8.8.8.8:53",
"corp.com.", "2.2.2.2:53",
"bigco.net.", "3.3.3.3:53"),
},
},
{
name: "routes-multi-split",
in: Config{
Routes: upstreams(
"corp.com", "2.2.2.2:53",
"bigco.net", "3.3.3.3:53"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
MatchDomains: fqdns("bigco.net", "corp.com"),
},
rs: resolver.Config{
Routes: upstreams(
"corp.com.", "2.2.2.2:53",
"bigco.net.", "3.3.3.3:53"),
},
},
{
name: "magic",
in: Config{
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
AuthoritativeSuffixes: fqdns("ts.com"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
bs: OSConfig{
Nameservers: mustIPs("8.8.8.8"),
SearchDomains: fqdns("coffee.shop"),
},
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf", "coffee.shop"),
},
rs: resolver.Config{
Routes: upstreams(".", "8.8.8.8:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
LocalDomains: fqdns("ts.com."),
},
},
{
name: "magic-split",
in: Config{
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
AuthoritativeSuffixes: fqdns("ts.com"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
MatchDomains: fqdns("ts.com"),
},
rs: resolver.Config{
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
LocalDomains: fqdns("ts.com."),
},
},
{
name: "routes-magic",
in: Config{
Routes: upstreams("corp.com", "2.2.2.2:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
AuthoritativeSuffixes: fqdns("ts.com"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
bs: OSConfig{
Nameservers: mustIPs("8.8.8.8"),
SearchDomains: fqdns("coffee.shop"),
},
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf", "coffee.shop"),
},
rs: resolver.Config{
Routes: upstreams(
"corp.com.", "2.2.2.2:53",
".", "8.8.8.8:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
LocalDomains: fqdns("ts.com."),
},
},
{
name: "routes-magic-split",
in: Config{
Routes: upstreams("corp.com", "2.2.2.2:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
AuthoritativeSuffixes: fqdns("ts.com"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
},
split: true,
os: OSConfig{
Nameservers: mustIPs("100.100.100.100"),
SearchDomains: fqdns("tailscale.com", "universe.tf"),
MatchDomains: fqdns("corp.com", "ts.com"),
},
rs: resolver.Config{
Routes: upstreams("corp.com.", "2.2.2.2:53"),
Hosts: hosts(
"dave.ts.com.", "1.2.3.4",
"bradfitz.ts.com.", "2.3.4.5"),
LocalDomains: fqdns("ts.com."),
},
},
}
for _, test := range tests {
t.Run(test.name, func(t *testing.T) {
f := fakeOSConfigurator{
SplitDNS: test.split,
BaseConfig: test.bs,
}
m := NewManager(t.Logf, &f, nil)
m.resolver.TestOnlySetHook(f.SetResolver)
if err := m.Set(test.in); err != nil {
t.Fatalf("m.Set: %v", err)
}
tr := cmp.Transformer("ipStr", func(ip netaddr.IP) string { return ip.String() })
if diff := cmp.Diff(f.OSConfig, test.os, tr, cmpopts.EquateEmpty()); diff != "" {
t.Errorf("wrong OSConfig (-got+want)\n%s", diff)
}
if diff := cmp.Diff(f.ResolverConfig, test.rs, tr, cmpopts.EquateEmpty()); diff != "" {
t.Errorf("wrong resolver.Config (-got+want)\n%s", diff)
}
})
}
}
func mustIPs(strs ...string) (ret []netaddr.IP) {
for _, s := range strs {
ret = append(ret, netaddr.MustParseIP(s))
}
return ret
}
func mustIPPs(strs ...string) (ret []netaddr.IPPort) {
for _, s := range strs {
ret = append(ret, netaddr.MustParseIPPort(s))
}
return ret
}
func fqdns(strs ...string) (ret []dnsname.FQDN) {
for _, s := range strs {
fqdn, err := dnsname.ToFQDN(s)
if err != nil {
panic(err)
}
ret = append(ret, fqdn)
}
return ret
}
func hosts(strs ...string) (ret map[dnsname.FQDN][]netaddr.IP) {
var key dnsname.FQDN
ret = map[dnsname.FQDN][]netaddr.IP{}
for _, s := range strs {
if ip, err := netaddr.ParseIP(s); err == nil {
if key == "" {
panic("IP provided before name")
}
ret[key] = append(ret[key], ip)
} else {
fqdn, err := dnsname.ToFQDN(s)
if err != nil {
panic(err)
}
key = fqdn
}
}
return ret
}
func upstreams(strs ...string) (ret map[dnsname.FQDN][]netaddr.IPPort) {
var key dnsname.FQDN
ret = map[dnsname.FQDN][]netaddr.IPPort{}
for _, s := range strs {
if ipp, err := netaddr.ParseIPPort(s); err == nil {
if key == "" {
panic("IPPort provided before suffix")
}
ret[key] = append(ret[key], ipp)
} else {
fqdn, err := dnsname.ToFQDN(s)
if err != nil {
panic(err)
}
key = fqdn
}
}
return ret
}