Pull request: home: rollback serveraddresses in mobileconfig

Updates #3607.

Squashed commit of the following:

commit 1f0a970b4265a59819ec139e51c98dc9376d995b
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Sep 30 13:26:49 2021 +0300

    home: rollback serveraddresses in mobileconfig

CHANGELOG.md

@@ -15,8 +15,6 @@ and this project adheres to
 
 ### Added
 
-- DNS server IP addresses to the `mobileconfig` API responses ([#3568],
-  [#3607]).
 - Setting the timeout for IP address pinging in the "Fastest IP address" mode
   through the new `fastest_timeout` field in the configuration file ([#1992]).
 - Static IP address detection on FreeBSD ([#3289]).
@@ -116,7 +114,8 @@ In this release, the schema version has changed from 10 to 12.
 
 ### Fixed
 
-- Adding an IP into only one of the matching ipsets on Linux ([#3638]).
+- Addition of IPs into only one as opposed to all matching ipsets on Linux
+  ([#3638]).
 - Removal of temporary filter files ([#3567]).
 - Panic when an upstream server responds with an empty question section
   ([#3551]).

internal/home/mobileconfig.go

@@ -32,6 +32,10 @@ type dnsSettings struct {
 	ServerName string `plist:",omitempty"`
 
 	// ServerAddresses is a list IP addresses of the server.
+	//
+	// TODO(a.garipov): Allow users to set this.
+	//
+	// See https://github.com/AdguardTeam/AdGuardHome/issues/3607.
 	ServerAddresses []net.IP `plist:",omitempty"`
 }
 
@@ -157,19 +161,9 @@ func handleMobileConfig(w http.ResponseWriter, r *http.Request, dnsp string) {
 		}
 	}
 
-	dnsIPs, err := collectDNSIPs()
-	if err != nil {
-		// Don't add a lot of formatting, since the error is already
-		// wrapped by collectDNSIPs.
-		respondJSONError(w, http.StatusInternalServerError, err.Error())
-
-		return
-	}
-
 	d := &dnsSettings{
-		DNSProtocol:     dnsp,
-		ServerName:      host,
-		ServerAddresses: dnsIPs,
+		DNSProtocol: dnsp,
+		ServerName:  host,
 	}
 
 	mobileconfig, err := encodeMobileConfig(d, clientID)
@@ -203,25 +197,3 @@ func handleMobileConfigDoH(w http.ResponseWriter, r *http.Request) {
 func handleMobileConfigDoT(w http.ResponseWriter, r *http.Request) {
 	handleMobileConfig(w, r, dnsProtoTLS)
 }
-
-// collectDNSIPs returns a slice of IP addresses the server is listening
-// on, including the addresses on all interfaces in cases of unspecified IPs but
-// excluding loopback addresses.
-func collectDNSIPs() (ips []net.IP, err error) {
-	// TODO(a.garipov): This really shouldn't be a function that parses
-	// a list of strings.  Instead, we need a function that returns this
-	// data as []net.IP or []*netutil.IPPort.  Maybe someday.
-	addrs, err := collectDNSAddresses()
-	if err != nil {
-		return nil, err
-	}
-
-	for _, addr := range addrs {
-		ip := net.ParseIP(addr)
-		if ip != nil && !ip.IsLoopback() {
-			ips = append(ips, ip)
-		}
-	}
-
-	return ips, nil
-}

internal/home/mobileconfig_test.go

@@ -58,7 +58,6 @@ func TestHandleMobileConfigDoH(t *testing.T) {
 		s := mc.PayloadContent[0].DNSSettings
 		require.NotNil(t, s)
 
-		assert.NotEmpty(t, s.ServerAddresses)
 		assert.Empty(t, s.ServerName)
 		assert.Equal(t, "https://example.org/dns-query", s.ServerURL)
 	})
@@ -104,7 +103,6 @@ func TestHandleMobileConfigDoH(t *testing.T) {
 		s := mc.PayloadContent[0].DNSSettings
 		require.NotNil(t, s)
 
-		assert.NotEmpty(t, s.ServerAddresses)
 		assert.Empty(t, s.ServerName)
 		assert.Equal(t, "https://example.org/dns-query/cli42", s.ServerURL)
 	})
@@ -132,7 +130,6 @@ func TestHandleMobileConfigDoT(t *testing.T) {
 		s := mc.PayloadContent[0].DNSSettings
 		require.NotNil(t, s)
 
-		assert.NotEmpty(t, s.ServerAddresses)
 		assert.Equal(t, "example.org", s.ServerName)
 		assert.Empty(t, s.ServerURL)
 	})
@@ -179,7 +176,6 @@ func TestHandleMobileConfigDoT(t *testing.T) {
 		s := mc.PayloadContent[0].DNSSettings
 		require.NotNil(t, s)
 
-		assert.NotEmpty(t, s.ServerAddresses)
 		assert.Equal(t, "cli42.example.org", s.ServerName)
 		assert.Empty(t, s.ServerURL)
 	})