home: add an option to disable autohosts

AdguardTeam · Apr 12, 2021 · 9058977 · 9058977
1 parent 8b8319f
commit 9058977
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Showing 6 changed files with 43 additions and 7 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -15,6 +15,8 @@ and this project adheres to
 
 ### Added
 
+- New startup option `--no-localhosts` to disable using OS-provided local hosts'
+  file as a source ([#1947]).
 - The ability to set up custom upstreams to resolve PTR queries for local
   addresses and to disable the automatic resolving of clients' addresses
   ([#2704]).
@@ -54,6 +56,7 @@ and this project adheres to
 
 [#1273]: https://github.com/AdguardTeam/AdGuardHome/issues/1273
 [#1401]: https://github.com/AdguardTeam/AdGuardHome/issues/1401
+[#1947]: https://github.com/AdguardTeam/AdGuardHome/issues/1947
 [#2385]: https://github.com/AdguardTeam/AdGuardHome/issues/2385
 [#2393]: https://github.com/AdguardTeam/AdGuardHome/issues/2393
 [#2412]: https://github.com/AdguardTeam/AdGuardHome/issues/2412

diff --git a/internal/home/clients.go b/internal/home/clients.go
@@ -114,15 +114,19 @@ func (clients *clientsContainer) Init(objects []clientObject, dhcpServer *dhcpd.
 	}
 
 	clients.dhcpServer = dhcpServer
-	clients.autoHosts = autoHosts
+	if autoHosts != nil {
+		clients.autoHosts = autoHosts
+	}
 	clients.addFromConfig(objects)
 
 	if !clients.testing {
 		clients.addFromDHCP()
 		if clients.dhcpServer != nil {
 			clients.dhcpServer.SetOnLeaseChanged(clients.onDHCPLeaseChanged)
 		}
-		clients.autoHosts.SetOnChanged(clients.onHostsChanged)
+		if clients.autoHosts != nil {
+			clients.autoHosts.SetOnChanged(clients.onHostsChanged)
+		}
 	}
 }
 
@@ -692,6 +696,10 @@ func (clients *clientsContainer) rmHostsBySrc(src clientSource) {
 // addFromHostsFile fills the client-hostname pairing index from the system's
 // hosts files.
 func (clients *clientsContainer) addFromHostsFile() {
+	if clients.autoHosts == nil {
+		return
+	}
+
 	hosts := clients.autoHosts.List()
 
 	clients.lock.Lock()

diff --git a/internal/home/dns.go b/internal/home/dns.go
@@ -57,7 +57,7 @@ func initDNSServer() error {
 	Context.queryLog = querylog.New(conf)
 
 	filterConf := config.DNS.DnsfilterConf
-	filterConf.AutoHosts = &Context.autoHosts
+	filterConf.AutoHosts = Context.autoHosts
 	filterConf.ConfigModified = onConfigModified
 	filterConf.HTTPRegister = httpRegister
 	Context.dnsFilter = dnsfilter.New(&filterConf, nil)

diff --git a/internal/home/home.go b/internal/home/home.go
@@ -58,7 +58,7 @@ type homeContext struct {
 	filters    Filtering            // DNS filtering module
 	web        *Web                 // Web (HTTP, HTTPS) module
 	tls        *TLSMod              // TLS module
-	autoHosts  util.AutoHosts       // IP-hostname pairs taken from system configuration (e.g. /etc/hosts) files
+	autoHosts  *util.AutoHosts      // IP-hostname pairs taken from system configuration (e.g. /etc/hosts) files
 	updater    *updater.Updater
 
 	subnetDetector *aghnet.SubnetDetector
@@ -186,8 +186,6 @@ func setupConfig(args options) {
 		log.Fatalf("can't initialize dhcp module")
 	}
 
-	Context.autoHosts.Init("")
-
 	Context.updater = updater.NewUpdater(&updater.Config{
 		Client:   Context.client,
 		Version:  version.Version(),
@@ -200,7 +198,11 @@ func setupConfig(args options) {
 		ConfName: config.getConfigFilename(),
 	})
 
-	Context.clients.Init(config.Clients, Context.dhcpServer, &Context.autoHosts)
+	if !args.noLocalHosts {
+		Context.autoHosts = &util.AutoHosts{}
+		Context.autoHosts.Init("")
+		Context.clients.Init(config.Clients, Context.dhcpServer, Context.autoHosts)
+	}
 	config.Clients = nil
 
 	if (runtime.GOOS == "linux" || runtime.GOOS == "darwin") &&

diff --git a/internal/home/options.go b/internal/home/options.go
@@ -32,6 +32,10 @@ type options struct {
 	disableMemoryOptimization bool
 
 	glinetMode bool // Activate GL-Inet compatibility mode
+
+	// noLocalHosts flag should be provided when /etc/hosts file shouldn't be
+	// used.
+	noLocalHosts bool
 }
 
 // functions used for their side-effects
@@ -220,6 +224,16 @@ var helpArg = arg{
 	func(o options) []string { return nil },
 }
 
+var noAutohostsArg = arg{
+	description:     "Do not use the OS-provided hosts.",
+	longName:        "no-localhosts",
+	shortName:       "",
+	updateWithValue: nil,
+	updateNoValue:   func(o options) (options, error) { o.noLocalHosts = true; return o, nil },
+	effect:          nil,
+	serialize:       func(o options) []string { return boolSliceOrNil(o.noLocalHosts) },
+}
+
 func init() {
 	args = []arg{
 		configArg,
@@ -236,6 +250,7 @@ func init() {
 		glinetArg,
 		versionArg,
 		helpArg,
+		noAutohostsArg,
 	}
 }
 

diff --git a/internal/util/autohosts.go b/internal/util/autohosts.go
@@ -90,6 +90,10 @@ func (a *AutoHosts) Init(hostsFn string) {
 
 // Start - start module
 func (a *AutoHosts) Start() {
+	if a == nil {
+		return
+	}
+
 	log.Debug("Start AutoHosts module")
 
 	a.updateHosts()
@@ -113,6 +117,10 @@ func (a *AutoHosts) Start() {
 
 // Close - close module
 func (a *AutoHosts) Close() {
+	if a == nil {
+		return
+	}
+
 	if a.watcher != nil {
 		_ = a.watcher.Close()
 	}