Pull request: all: allow local non-top-level domains

Updates #2961.

Squashed commit of the following:

commit 207eeb85caf6caee81a669302daf4e10a5b61585
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Apr 15 18:48:50 2021 +0300

    all: allow local non-top-level domains

CHANGELOG.md

@@ -24,7 +24,8 @@ and this project adheres to
 - Logging of the client's IP address after failed login attempts ([#2824]).
 - Search by clients' names in the query log ([#1273]).
 - Verbose version output with `-v --version` ([#2416]).
-- The ability to set a custom TLD for known local-network hosts ([#2393]).
+- The ability to set a custom TLD or domain name for known hosts in the local
+  network ([#2393], [#2961]).
 - The ability to serve DNS queries on multiple hosts and interfaces ([#1401]).
 - `ips` and `text` DHCP server options ([#2385]).
 - `SRV` records support in `$dnsrewrite` filters ([#2533]).
@@ -80,6 +81,7 @@ and this project adheres to
 [#2934]: https://github.com/AdguardTeam/AdGuardHome/issues/2934
 [#2945]: https://github.com/AdguardTeam/AdGuardHome/issues/2945
 [#2947]: https://github.com/AdguardTeam/AdGuardHome/issues/2947
+[#2961]: https://github.com/AdguardTeam/AdGuardHome/issues/2961
 
 
 

internal/dnsfilter/dnsfilter.go

@@ -422,9 +422,9 @@ func (d *DNSFilter) CheckHost(
 	return Result{}, nil
 }
 
-// checkAutoHosts compares the host against our autohosts table.  The err is
+// checkEtcHosts compares the host against our /etc/hosts table.  The err is
 // always nil, it is only there to make this a valid hostChecker function.
-func (d *DNSFilter) checkAutoHosts(
+func (d *DNSFilter) checkEtcHosts(
 	host string,
 	qtype uint16,
 	_ *FilteringSettings,
@@ -829,8 +829,8 @@ func New(c *Config, blockFilters []Filter) *DNSFilter {
 	}
 
 	d.hostCheckers = []hostChecker{{
-		check: d.checkAutoHosts,
-		name:  "autohosts",
+		check: d.checkEtcHosts,
+		name:  "etchosts",
 	}, {
 		check: d.matchHost,
 		name:  "filtering",

internal/dnsforward/dns.go

@@ -264,7 +264,7 @@ func (s *Server) processInternalHosts(dctx *dnsContext) (rc resultCode) {
 	}
 
 	reqHost := strings.ToLower(q.Name)
-	host := strings.TrimSuffix(reqHost, s.autohostSuffix)
+	host := strings.TrimSuffix(reqHost, s.localDomainSuffix)
 	if host == reqHost {
 		return resultCodeSuccess
 	}

internal/dnsforward/dns_test.go

@@ -90,7 +90,7 @@ func TestServer_ProcessInternalHosts_localRestriction(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			s := &Server{
-				autohostSuffix: defaultAutohostSuffix,
+				localDomainSuffix: defaultLocalDomainSuffix,
 				tableHostToIP: hostToIPTable{
 					"example": knownIP,
 				},
@@ -157,35 +157,35 @@ func TestServer_ProcessInternalHosts(t *testing.T) {
 	}{{
 		name:    "success_external",
 		host:    examplecom,
-		suffix:  defaultAutohostSuffix,
+		suffix:  defaultLocalDomainSuffix,
 		wantIP:  nil,
 		wantRes: resultCodeSuccess,
 		qtyp:    dns.TypeA,
 	}, {
 		name:    "success_external_non_a",
 		host:    examplecom,
-		suffix:  defaultAutohostSuffix,
+		suffix:  defaultLocalDomainSuffix,
 		wantIP:  nil,
 		wantRes: resultCodeSuccess,
 		qtyp:    dns.TypeCNAME,
 	}, {
 		name:    "success_internal",
 		host:    examplelan,
-		suffix:  defaultAutohostSuffix,
+		suffix:  defaultLocalDomainSuffix,
 		wantIP:  knownIP,
 		wantRes: resultCodeSuccess,
 		qtyp:    dns.TypeA,
 	}, {
 		name:    "success_internal_unknown",
 		host:    "example-new.lan",
-		suffix:  defaultAutohostSuffix,
+		suffix:  defaultLocalDomainSuffix,
 		wantIP:  nil,
 		wantRes: resultCodeFinish,
 		qtyp:    dns.TypeA,
 	}, {
 		name:    "success_internal_aaaa",
 		host:    examplelan,
-		suffix:  defaultAutohostSuffix,
+		suffix:  defaultLocalDomainSuffix,
 		wantIP:  nil,
 		wantRes: resultCodeSuccess,
 		qtyp:    dns.TypeAAAA,
@@ -201,7 +201,7 @@ func TestServer_ProcessInternalHosts(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			s := &Server{
-				autohostSuffix: tc.suffix,
+				localDomainSuffix: tc.suffix,
 				tableHostToIP: hostToIPTable{
 					"example": knownIP,
 				},

internal/dnsforward/dnsforward.go

@@ -70,9 +70,9 @@ type Server struct {
 	stats      stats.Stats
 	access     *accessCtx
 
-	// autohostSuffix is the suffix used to detect internal hosts.  It must
-	// be a valid top-level domain plus dots on each side.
-	autohostSuffix string
+	// localDomainSuffix is the suffix used to detect internal hosts.  It
+	// must be a valid domain name plus dots on each side.
+	localDomainSuffix string
 
 	ipset          ipsetCtx
 	subnetDetector *aghnet.SubnetDetector
@@ -94,9 +94,11 @@ type Server struct {
 	conf ServerConfig
 }
 
-// defaultAutohostSuffix is the default suffix used to detect internal hosts
-// when no suffix is provided.  See the documentation for Server.autohostSuffix.
-const defaultAutohostSuffix = ".lan."
+// defaultLocalDomainSuffix is the default suffix used to detect internal hosts
+// when no suffix is provided.
+//
+// See the documentation for Server.localDomainSuffix.
+const defaultLocalDomainSuffix = ".lan."
 
 // DNSCreateParams are parameters to create a new server.
 type DNSCreateParams struct {
@@ -105,11 +107,11 @@ type DNSCreateParams struct {
 	QueryLog       querylog.QueryLog
 	DHCPServer     dhcpd.ServerInterface
 	SubnetDetector *aghnet.SubnetDetector
-	AutohostTLD    string
+	LocalDomain    string
 }
 
-// tldToSuffix converts a top-level domain into an autohost suffix.
-func tldToSuffix(tld string) (suffix string) {
+// domainNameToSuffix converts a domain name into a local domain suffix.
+func domainNameToSuffix(tld string) (suffix string) {
 	l := len(tld) + 2
 	b := make([]byte, l)
 	b[0] = '.'
@@ -122,24 +124,24 @@ func tldToSuffix(tld string) (suffix string) {
 // NewServer creates a new instance of the dnsforward.Server
 // Note: this function must be called only once
 func NewServer(p DNSCreateParams) (s *Server, err error) {
-	var autohostSuffix string
-	if p.AutohostTLD == "" {
-		autohostSuffix = defaultAutohostSuffix
+	var localDomainSuffix string
+	if p.LocalDomain == "" {
+		localDomainSuffix = defaultLocalDomainSuffix
 	} else {
-		err = aghnet.ValidateDomainNameLabel(p.AutohostTLD)
+		err = aghnet.ValidateDomainName(p.LocalDomain)
 		if err != nil {
-			return nil, fmt.Errorf("autohost tld: %w", err)
+			return nil, fmt.Errorf("local domain: %w", err)
 		}
 
-		autohostSuffix = tldToSuffix(p.AutohostTLD)
+		localDomainSuffix = domainNameToSuffix(p.LocalDomain)
 	}
 
 	s = &Server{
-		dnsFilter:      p.DNSFilter,
-		stats:          p.Stats,
-		queryLog:       p.QueryLog,
-		subnetDetector: p.SubnetDetector,
-		autohostSuffix: autohostSuffix,
+		dnsFilter:         p.DNSFilter,
+		stats:             p.Stats,
+		queryLog:          p.QueryLog,
+		subnetDetector:    p.SubnetDetector,
+		localDomainSuffix: localDomainSuffix,
 	}
 
 	if p.DHCPServer != nil {

internal/dnsforward/dnsforward_test.go

@@ -232,10 +232,10 @@ func sendTestMessages(t *testing.T, conn *dns.Conn) {
 	for i := 0; i < testMessagesCount; i++ {
 		req := createGoogleATestMessage()
 		err := conn.WriteMsg(req)
-		assert.Nilf(t, err, "cannot write message #%d: %s", i, err)
+		assert.NoErrorf(t, err, "cannot write message #%d: %s", i, err)
 
 		res, err := conn.ReadMsg()
-		assert.Nilf(t, err, "cannot read response to message #%d: %s", i, err)
+		assert.NoErrorf(t, err, "cannot read response to message #%d: %s", i, err)
 		assertGoogleAResponse(t, res)
 	}
 }
@@ -1088,7 +1088,6 @@ func TestPTRResponseFromHosts(t *testing.T) {
 	_, _ = hf.WriteString("  127.0.0.1   host # comment \n")
 	_, _ = hf.WriteString("  ::1   localhost#comment  \n")
 
-	// Init auto hosts.
 	c.EtcHosts.Init(hf.Name())
 	t.Cleanup(c.EtcHosts.Close)
 
@@ -1145,17 +1144,24 @@ func TestNewServer(t *testing.T) {
 		in:         DNSCreateParams{},
 		wantErrMsg: "",
 	}, {
-		name: "success_autohost_tld",
+		name: "success_local_tld",
 		in: DNSCreateParams{
-			AutohostTLD: "mynet",
+			LocalDomain: "mynet",
 		},
 		wantErrMsg: "",
 	}, {
-		name: "bad_autohost_tld",
+		name: "success_local_domain",
 		in: DNSCreateParams{
-			AutohostTLD: "!!!",
+			LocalDomain: "my.local.net",
 		},
-		wantErrMsg: `autohost tld: invalid char '!' at index 0 in "!!!"`,
+		wantErrMsg: "",
+	}, {
+		name: "bad_local_domain",
+		in: DNSCreateParams{
+			LocalDomain: "!!!",
+		},
+		wantErrMsg: `local domain: invalid domain name label at index 0: ` +
+			`invalid char '!' at index 0 in "!!!"`,
 	}}
 
 	for _, tc := range testCases {

internal/home/clientshttp.go

@@ -237,7 +237,7 @@ func (clients *clientsContainer) handleFindClient(w http.ResponseWriter, r *http
 		var cj clientJSON
 		if !ok {
 			var found bool
-			cj, found = clients.findTemporary(ip, idStr)
+			cj, found = clients.findRuntime(ip, idStr)
 			if !found {
 				continue
 			}
@@ -258,9 +258,9 @@ func (clients *clientsContainer) handleFindClient(w http.ResponseWriter, r *http
 	}
 }
 
-// findTemporary looks up the IP in temporary storages, like autohosts or
-// blocklists.
-func (clients *clientsContainer) findTemporary(ip net.IP, idStr string) (cj clientJSON, found bool) {
+// findRuntime looks up the IP in runtime and temporary storages, like
+// /etc/hosts tables, DHCP leases, or blocklists.
+func (clients *clientsContainer) findRuntime(ip net.IP, idStr string) (cj clientJSON, found bool) {
 	if ip == nil {
 		return cj, false
 	}

internal/home/config.go

@@ -94,10 +94,10 @@ type dnsConfig struct {
 	FiltersUpdateIntervalHours uint32           `yaml:"filters_update_interval"` // time period to update filters (in hours)
 	DnsfilterConf              dnsfilter.Config `yaml:",inline"`
 
-	// AutohostTLD is the top-level domain used for known internal hosts.
+	// LocalDomainName is the domain name used for known internal hosts.
 	// For example, a machine called "myhost" can be addressed as
-	// "myhost.lan" when AutohostTLD is "lan".
-	AutohostTLD string `yaml:"autohost_tld"`
+	// "myhost.lan" when LocalDomainName is "lan".
+	LocalDomainName string `yaml:"local_domain_name"`
 
 	// ResolveClients enables and disables resolving clients with RDNS.
 	ResolveClients bool `yaml:"resolve_clients"`
@@ -156,7 +156,7 @@ var config = configuration{
 		},
 		FilteringEnabled:           true, // whether or not use filter lists
 		FiltersUpdateIntervalHours: 24,
-		AutohostTLD:                "lan",
+		LocalDomainName:            "lan",
 		ResolveClients:             true,
 	},
 	TLS: tlsConfigSettings{

internal/home/dns.go

@@ -67,7 +67,7 @@ func initDNSServer() error {
 		Stats:          Context.stats,
 		QueryLog:       Context.queryLog,
 		SubnetDetector: Context.subnetDetector,
-		AutohostTLD:    config.DNS.AutohostTLD,
+		LocalDomain:    config.DNS.LocalDomainName,
 	}
 	if Context.dhcpServer != nil {
 		p.DHCPServer = Context.dhcpServer

internal/home/upgrade.go

@@ -14,7 +14,7 @@ import (
 )
 
 // currentSchemaVersion is the current schema version.
-const currentSchemaVersion = 8
+const currentSchemaVersion = 9
 
 // These aliases are provided for convenience.
 type (
@@ -74,6 +74,7 @@ func upgradeConfigSchema(oldVersion int, diskConf yobj) (err error) {
 		upgradeSchema5to6,
 		upgradeSchema6to7,
 		upgradeSchema7to8,
+		upgradeSchema8to9,
 	}
 
 	n := 0
@@ -464,6 +465,43 @@ func upgradeSchema7to8(diskConf yobj) (err error) {
 	return nil
 }
 
+// upgradeSchema8to9 performs the following changes:
+//
+//   # BEFORE:
+//   'dns':
+//     'autohost_tld': 'lan'
+//
+//   # AFTER:
+//   'dns':
+//     'local_domain_name': 'lan'
+//
+func upgradeSchema8to9(diskConf yobj) (err error) {
+	log.Printf("Upgrade yaml: 8 to 9")
+
+	diskConf["schema_version"] = 9
+
+	dnsVal, ok := diskConf["dns"]
+	if !ok {
+		return nil
+	}
+
+	dns, ok := dnsVal.(yobj)
+	if !ok {
+		return fmt.Errorf("unexpected type of dns: %T", dnsVal)
+	}
+
+	autohostTLDVal := dns["autohost_tld"]
+	autohostTLD, ok := autohostTLDVal.(string)
+	if !ok {
+		return fmt.Errorf("undexpected type of dns.autohost_tld: %T", autohostTLDVal)
+	}
+
+	delete(dns, "autohost_tld")
+	dns["local_domain_name"] = autohostTLD
+
+	return nil
+}
+
 // TODO(a.garipov): Replace with log.Output when we port it to our logging
 // package.
 func funcName() string {

internal/home/upgrade_test.go

@@ -13,7 +13,7 @@ func TestUpgradeSchema1to2(t *testing.T) {
 	diskConf := testDiskConf(1)
 
 	err := upgradeSchema1to2(diskConf)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	require.Equal(t, diskConf["schema_version"], 2)
 
@@ -36,7 +36,7 @@ func TestUpgradeSchema2to3(t *testing.T) {
 	diskConf := testDiskConf(2)
 
 	err := upgradeSchema2to3(diskConf)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	require.Equal(t, diskConf["schema_version"], 3)
 
@@ -74,7 +74,7 @@ func TestUpgradeSchema7to8(t *testing.T) {
 	}
 
 	err := upgradeSchema7to8(oldConf)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	require.Equal(t, oldConf["schema_version"], 8)
 
@@ -90,6 +90,32 @@ func TestUpgradeSchema7to8(t *testing.T) {
 	assert.Equal(t, host, newBindHosts[0])
 }
 
+func TestUpgradeSchema8to9(t *testing.T) {
+	const tld = "foo"
+	oldConf := yobj{
+		"dns": yobj{
+			"autohost_tld": tld,
+		},
+		"schema_version": 8,
+	}
+
+	err := upgradeSchema8to9(oldConf)
+	require.NoError(t, err)
+
+	require.Equal(t, oldConf["schema_version"], 9)
+
+	dnsVal, ok := oldConf["dns"]
+	require.True(t, ok)
+
+	newDNSConf, ok := dnsVal.(yobj)
+	require.True(t, ok)
+
+	localDomainName, ok := newDNSConf["local_domain_name"].(string)
+	require.True(t, ok)
+
+	assert.Equal(t, tld, localDomainName)
+}
+
 // assertEqualExcept removes entries from configs and compares them.
 func assertEqualExcept(t *testing.T, oldConf, newConf yobj, oldKeys, newKeys []string) {
 	t.Helper()