Pull request 1744: 1472-edns-custom-ip

Merge in DNS/adguard-home from 1472-edns-custom-ip to master

Updates #1472.

Squashed commit of the following:

commit 07460c3adf7747fd9ec1b4a3d04fb459dec44280
Merge: 65455430 ae653f16
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Mar 1 15:38:46 2023 +0300

    Merge branch 'master' into 1472-edns-custom-ip

commit 65455430993e4a62c49e1f45def909b0a135af3b
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Mar 1 15:37:17 2023 +0300

    dnsforward: add todo

commit e1978ad4b6051f29185ef32973d20bc70f2a6634
Merge: 6cd98f42 bb226434
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Mar 1 11:32:23 2023 +0300

    Merge branch 'master' into 1472-edns-custom-ip

commit 6cd98f4235b1b52d443c1950f2516af3cc4fb258
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Mar 1 11:31:16 2023 +0300

    all: fix chlog; fix field alignment

commit defdec623919c23ab446324828d08839469669e1
Merge: 1130ebd5 a772212d
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Feb 28 12:17:23 2023 +0300

    Merge branch 'master' into 1472-edns-custom-ip

commit 1130ebd509bf4f7ec25fbb53717576e273dbfff2
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Feb 28 12:13:30 2023 +0300

    all: add use_custom field

commit ec0cdc7af0f96f761ed85516bbcae2567fd6f7d2
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 27 13:59:13 2023 +0300

    all: fix chlog; imp code

commit f8450cfcd6054f32d6ea0a5e26c551fe153a0b21
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 27 11:28:16 2023 +0300

    dnsforward: fix fmt

commit 54a344e5bb17aae7ca213ed66b85f06ef6585316
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 27 11:11:52 2023 +0300

    all: fix chlog; add test case

commit 47b5476f6621c6ea31aa496d4113445a8e8bceb4
Merge: 8724f374 304f2ba2
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 22 16:33:07 2023 +0300

    Merge branch 'master' into 1472-edns-custom-ip

commit 8724f3745ccc29849a4001f79b055c7ebeb19106
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 22 16:31:40 2023 +0300

    all: fix comments

commit d2b1528ba333e7669795a3fb80355ff7d90cf4f5
Merge: 7898c23a 76a513cd
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 22 11:53:25 2023 +0300

    Merge branch 'master' into 1472-edns-custom-ip

commit 7898c23ab991bc516bcc2f41e47bed15582fd962
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 22 11:52:37 2023 +0300

    all: upd chlog

commit 8763261dcb4187a93104955e7cb440965e2b6739
Merge: d28394b3 ff9b24ad
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Feb 21 17:12:03 2023 +0300

    Merge branch 'master' into 1472-edns-custom-ip

commit d28394b3c980b10f28c6c38ce35f368edb11d314
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Feb 21 17:11:29 2023 +0300

    home: fix default value

commit 1a5da3f267706baa83eebe1923ea1b0b4e79fd6c
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Feb 21 13:37:04 2023 +0300

    all: add custom ip for edns

CHANGELOG.md

@@ -25,9 +25,43 @@ NOTE: Add new changes BELOW THIS COMMENT.
 
 ### Added
 
+- The ability to set custom IP for EDNS Client Subnet by using the new
+  `dns.edns_client_subnet.use_custom` and `dns.edns_client_subnet.custom_ip`
+  fields ([#1472]).  The UI changes are coming in the upcoming releases.
 - The ability to use `dnstype` rules in the disallowed domains list ([#5468]).
   This allows dropping requests based on their question types.
 
+### Changed
+
+#### Configuration Changes
+
+In this release, the schema version has changed from 16 to 17.
+
+- Property `edns_client_subnet`, which in schema versions 16 and earlier used
+  to be a part of the `dns` object, is now part of the `dns.edns_client_subnet`
+  object:
+
+  ```yaml
+  # BEFORE:
+  'dns':
+    # …
+    'edns_client_subnet': false
+
+  # AFTER:
+  'dns':
+    # …
+    'edns_client_subnet':
+      'enabled': false
+      'use_custom': false
+      'custom_ip': ''
+  ```
+
+  To rollback this change, move the value of `dns.edns_client_subnet.enabled`
+  into the `dns.edns_client_subnet`, remove the fields
+  `dns.edns_client_subnet.enabled`, `dns.edns_client_subnet.use_custom`,
+  `dns.edns_client_subnet.custom_ip`, and change the `schema_version` back to
+  `16`.
+
 ### Fixed
 
 - Various dark theme bugs ([#5439], [#5441], [#5442], [#5515]).
@@ -37,6 +71,7 @@ NOTE: Add new changes BELOW THIS COMMENT.
   been relaxed to meet those from [RFC 3696][rfc3696] ([#4884]).
 - Failing service installation via script on FreeBSD ([#5431]).
 
+[#1472]: https://github.com/AdguardTeam/AdGuardHome/issues/1472
 [#4884]: https://github.com/AdguardTeam/AdGuardHome/issues/4884
 [#5270]: https://github.com/AdguardTeam/AdGuardHome/issues/5270
 [#5373]: https://github.com/AdguardTeam/AdGuardHome/issues/5373
@@ -129,6 +164,7 @@ In this release, the schema version has changed from 14 to 16.
     'file_enabled': true
     'interval': '2160h'
     'size_memory': 1000
+    'ignored': []
   ```
 
   To rollback this change, rename and move properties back into the `dns`

internal/dnsforward/config.go

@@ -53,7 +53,6 @@ const (
 // The zero FilteringConfig is empty and ready for use.
 type FilteringConfig struct {
 	// Callbacks for other modules
-	// --
 
 	// FilterHandler is an optional additional filtering callback.
 	FilterHandler func(clientAddr net.IP, clientID string, settings *filtering.Settings) `yaml:"-"`
@@ -64,50 +63,82 @@ type FilteringConfig struct {
 	GetCustomUpstreamByClient func(id string) (conf *proxy.UpstreamConfig, err error) `yaml:"-"`
 
 	// Protection configuration
-	// --
 
-	ProtectionEnabled  bool         `yaml:"protection_enabled"`   // whether or not use any of filtering features
+	// ProtectionEnabled defines whether or not use any of filtering features.
-	BlockingMode       BlockingMode `yaml:"blocking_mode"`        // mode how to answer filtered requests
+	ProtectionEnabled bool `yaml:"protection_enabled"`
-	BlockingIPv4       net.IP       `yaml:"blocking_ipv4"`        // IP address to be returned for a blocked A request
-	BlockingIPv6       net.IP       `yaml:"blocking_ipv6"`        // IP address to be returned for a blocked AAAA request
-	BlockedResponseTTL uint32       `yaml:"blocked_response_ttl"` // if 0, then default is used (3600)
 
-	// IP (or domain name) which is used to respond to DNS requests blocked by parental control or safe-browsing
+	// BlockingMode defines the way how blocked responses are constructed.
-	ParentalBlockHost     string `yaml:"parental_block_host"`
+	BlockingMode BlockingMode `yaml:"blocking_mode"`
+
+	// BlockingIPv4 is the IP address to be returned for a blocked A request.
+	BlockingIPv4 net.IP `yaml:"blocking_ipv4"`
+
+	// BlockingIPv6 is the IP address to be returned for a blocked AAAA
+	// request.
+	BlockingIPv6 net.IP `yaml:"blocking_ipv6"`
+
+	// BlockedResponseTTL is the time-to-live value for blocked responses.  If
+	// 0, then default value is used (3600).
+	BlockedResponseTTL uint32 `yaml:"blocked_response_ttl"`
+
+	// ParentalBlockHost is the IP (or domain name) which is used to respond to
+	// DNS requests blocked by parental control.
+	ParentalBlockHost string `yaml:"parental_block_host"`
+
+	// SafeBrowsingBlockHost is the IP (or domain name) which is used to
+	// respond to DNS requests blocked by safe-browsing.
 	SafeBrowsingBlockHost string `yaml:"safebrowsing_block_host"`
 
 	// Anti-DNS amplification
-	// --
 
-	Ratelimit          uint32   `yaml:"ratelimit"`           // max number of requests per second from a given IP (0 to disable)
+	// Ratelimit is the maximum number of requests per second from a given IP
-	RatelimitWhitelist []string `yaml:"ratelimit_whitelist"` // a list of whitelisted client IP addresses
+	// (0 to disable).
-	RefuseAny          bool     `yaml:"refuse_any"`          // if true, refuse ANY requests
+	Ratelimit uint32 `yaml:"ratelimit"`
+
+	// RatelimitWhitelist is the list of whitelisted client IP addresses.
+	RatelimitWhitelist []string `yaml:"ratelimit_whitelist"`
+
+	// RefuseAny, if true, refuse ANY requests.
+	RefuseAny bool `yaml:"refuse_any"`
 
 	// Upstream DNS servers configuration
-	// --
 
-	UpstreamDNS         []string `yaml:"upstream_dns"`
+	// UpstreamDNS is the list of upstream DNS servers.
-	UpstreamDNSFileName string   `yaml:"upstream_dns_file"`
+	UpstreamDNS []string `yaml:"upstream_dns"`
-	BootstrapDNS        []string `yaml:"bootstrap_dns"` // a list of bootstrap DNS for DoH and DoT (plain DNS only)
+
-	AllServers          bool     `yaml:"all_servers"`   // if true, parallel queries to all configured upstream servers are enabled
+	// UpstreamDNSFileName, if set, points to the file which contains upstream
-	FastestAddr         bool     `yaml:"fastest_addr"`  // use Fastest Address algorithm
+	// DNS servers.
+	UpstreamDNSFileName string `yaml:"upstream_dns_file"`
+
+	// BootstrapDNS is the list of bootstrap DNS servers for DoH and DoT
+	// resolvers (plain DNS only).
+	BootstrapDNS []string `yaml:"bootstrap_dns"`
+
+	// AllServers, if true, parallel queries to all configured upstream servers
+	// are enabled.
+	AllServers bool `yaml:"all_servers"`
+
+	// FastestAddr, if true, use Fastest Address algorithm.
+	FastestAddr bool `yaml:"fastest_addr"`
+
 	// FastestTimeout replaces the default timeout for dialing IP addresses
 	// when FastestAddr is true.
 	FastestTimeout timeutil.Duration `yaml:"fastest_timeout"`
 
 	// Access settings
-	// --
 
-	// AllowedClients is the slice of IP addresses, CIDR networks, and ClientIDs
+	// AllowedClients is the slice of IP addresses, CIDR networks, and
-	// of allowed clients.  If not empty, only these clients are allowed, and
+	// ClientIDs of allowed clients.  If not empty, only these clients are
-	// [FilteringConfig.DisallowedClients] are ignored.
+	// allowed, and [FilteringConfig.DisallowedClients] are ignored.
 	AllowedClients []string `yaml:"allowed_clients"`
 
 	// DisallowedClients is the slice of IP addresses, CIDR networks, and
 	// ClientIDs of disallowed clients.
 	DisallowedClients []string `yaml:"disallowed_clients"`
 
-	BlockedHosts []string `yaml:"blocked_hosts"` // hosts that should be blocked
+	// BlockedHosts is the list of hosts that should be blocked.
+	BlockedHosts []string `yaml:"blocked_hosts"`
+
 	// TrustedProxies is the list of IP addresses and CIDR networks to detect
 	// proxy servers addresses the DoH requests from which should be handled.
 	// The value of nil or an empty slice for this field makes Proxy not trust
@@ -115,26 +146,46 @@ type FilteringConfig struct {
 	TrustedProxies []string `yaml:"trusted_proxies"`
 
 	// DNS cache settings
-	// --
 
-	CacheSize   uint32 `yaml:"cache_size"`    // DNS cache size (in bytes)
+	// CacheSize is the DNS cache size (in bytes).
-	CacheMinTTL uint32 `yaml:"cache_ttl_min"` // override TTL value (minimum) received from upstream server
+	CacheSize uint32 `yaml:"cache_size"`
-	CacheMaxTTL uint32 `yaml:"cache_ttl_max"` // override TTL value (maximum) received from upstream server
+
+	// CacheMinTTL is the override TTL value (minimum) received from upstream
+	// server.
+	CacheMinTTL uint32 `yaml:"cache_ttl_min"`
+
+	// CacheMaxTTL is the override TTL value (maximum) received from upstream
+	// server.
+	CacheMaxTTL uint32 `yaml:"cache_ttl_max"`
+
 	// CacheOptimistic defines if optimistic cache mechanism should be used.
 	CacheOptimistic bool `yaml:"cache_optimistic"`
 
 	// Other settings
-	// --
 
-	BogusNXDomain          []string `yaml:"bogus_nxdomain"`     // transform responses with these IP addresses to NXDOMAIN
+	// BogusNXDomain is the list of IP addresses, responses with them will be
-	AAAADisabled           bool     `yaml:"aaaa_disabled"`      // Respond with an empty answer to all AAAA requests
+	// transformed to NXDOMAIN.
-	EnableDNSSEC           bool     `yaml:"enable_dnssec"`      // Set AD flag in outcoming DNS request
+	BogusNXDomain []string `yaml:"bogus_nxdomain"`
-	EnableEDNSClientSubnet bool     `yaml:"edns_client_subnet"` // Enable EDNS Client Subnet option
-	MaxGoroutines          uint32   `yaml:"max_goroutines"`     // Max. number of parallel goroutines for processing incoming requests
-	HandleDDR              bool     `yaml:"handle_ddr"`         // Handle DDR requests
 
-	// IpsetList is the ipset configuration that allows AdGuard Home to add
+	// AAAADisabled, if true, respond with an empty answer to all AAAA
-	// IP addresses of the specified domain names to an ipset list.  Syntax:
+	// requests.
+	AAAADisabled bool `yaml:"aaaa_disabled"`
+
+	// EnableDNSSEC, if true, set AD flag in outcoming DNS request.
+	EnableDNSSEC bool `yaml:"enable_dnssec"`
+
+	// EDNSClientSubnet is the settings list for EDNS Client Subnet.
+	EDNSClientSubnet *EDNSClientSubnet `yaml:"edns_client_subnet"`
+
+	// MaxGoroutines is the max number of parallel goroutines for processing
+	// incoming requests.
+	MaxGoroutines uint32 `yaml:"max_goroutines"`
+
+	// HandleDDR, if true, handle DDR requests
+	HandleDDR bool `yaml:"handle_ddr"`
+
+	// IpsetList is the ipset configuration that allows AdGuard Home to add IP
+	// addresses of the specified domain names to an ipset list.  Syntax:
 	//
 	//	DOMAIN[,DOMAIN].../IPSET_NAME
 	//
@@ -146,6 +197,18 @@ type FilteringConfig struct {
 	IpsetListFileName string `yaml:"ipset_file"`
 }
 
+// EDNSClientSubnet is the settings list for EDNS Client Subnet.
+type EDNSClientSubnet struct {
+	// CustomIP for EDNS Client Subnet.
+	CustomIP string `yaml:"custom_ip"`
+
+	// Enabled defines if EDNS Client Subnet is enabled.
+	Enabled bool `yaml:"enabled"`
+
+	// UseCustom defines if CustomIP should be used.
+	UseCustom bool `yaml:"use_custom"`
+}
+
 // TLSConfig is the TLS configuration for HTTPS, DNS-over-HTTPS, and DNS-over-TLS
 type TLSConfig struct {
 	cert tls.Certificate
@@ -270,12 +333,24 @@ func (s *Server) createProxyConfig() (conf proxy.Config, err error) {
 		UpstreamConfig:         srvConf.UpstreamConfig,
 		BeforeRequestHandler:   s.beforeRequestHandler,
 		RequestHandler:         s.handleDNSRequest,
-		EnableEDNSClientSubnet: srvConf.EnableEDNSClientSubnet,
+		EnableEDNSClientSubnet: srvConf.EDNSClientSubnet.Enabled,
 		MaxGoroutines:          int(srvConf.MaxGoroutines),
 		UseDNS64:               srvConf.UseDNS64,
 		DNS64Prefs:             srvConf.DNS64Prefixes,
 	}
 
+	if srvConf.EDNSClientSubnet.UseCustom {
+		// TODO(s.chzhen):  Add wrapper around netip.Addr.
+		var ip net.IP
+		ip, err = netutil.ParseIP(srvConf.EDNSClientSubnet.CustomIP)
+		if err != nil {
+			return conf, fmt.Errorf("edns: %w", err)
+		}
+
+		// TODO(s.chzhen):  Use netip.Addr instead of net.IP inside dnsproxy.
+		conf.EDNSAddr = ip
+	}
+
 	if srvConf.CacheSize != 0 {
 		conf.CacheEnabled = true
 		conf.CacheSizeBytes = int(srvConf.CacheSize)

internal/dnsforward/dns64_test.go

@@ -287,6 +287,9 @@ func TestServer_HandleDNSRequest_dns64(t *testing.T) {
 			UDPListenAddrs: []*net.UDPAddr{{}},
 			TCPListenAddrs: []*net.TCPAddr{{}},
 			UseDNS64:       true,
+			FilteringConfig: FilteringConfig{
+				EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+			},
 		}, localUps)
 
 		t.Run(tc.name, func(t *testing.T) {

internal/dnsforward/dns_test.go

@@ -467,6 +467,11 @@ func TestServer_ProcessRestrictLocal(t *testing.T) {
 	s := createTestServer(t, &filtering.Config{}, ServerConfig{
 		UDPListenAddrs: []*net.UDPAddr{{}},
 		TCPListenAddrs: []*net.TCPAddr{{}},
+		// TODO(s.chzhen):  Add tests where EDNSClientSubnet.Enabled is true.
+		// Improve FilteringConfig declaration for tests.
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+		},
 	}, ups)
 	s.conf.UpstreamConfig.Upstreams = []upstream.Upstream{ups}
 	startDeferStop(t, s)
@@ -539,6 +544,9 @@ func TestServer_ProcessLocalPTR_usingResolvers(t *testing.T) {
 		ServerConfig{
 			UDPListenAddrs: []*net.UDPAddr{{}},
 			TCPListenAddrs: []*net.TCPAddr{{}},
+			FilteringConfig: FilteringConfig{
+				EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+			},
 		},
 		aghtest.NewUpstreamMock(func(req *dns.Msg) (resp *dns.Msg, err error) {
 			return aghalg.Coalesce(

internal/dnsforward/dnsforward_test.go

@@ -156,6 +156,9 @@ func createTestTLS(t *testing.T, tlsConf TLSConfig) (s *Server, certPem []byte)
 	s = createTestServer(t, &filtering.Config{}, ServerConfig{
 		UDPListenAddrs: []*net.UDPAddr{{}},
 		TCPListenAddrs: []*net.TCPAddr{{}},
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+		},
 	}, nil)
 
 	tlsConf.CertificateChainData, tlsConf.PrivateKeyData = certPem, keyPem
@@ -267,6 +270,9 @@ func TestServer(t *testing.T) {
 	s := createTestServer(t, &filtering.Config{}, ServerConfig{
 		UDPListenAddrs: []*net.UDPAddr{{}},
 		TCPListenAddrs: []*net.TCPAddr{{}},
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+		},
 	}, nil)
 	s.conf.UpstreamConfig.Upstreams = []upstream.Upstream{newGoogleUpstream()}
 	startDeferStop(t, s)
@@ -305,7 +311,8 @@ func TestServer_timeout(t *testing.T) {
 		srvConf := &ServerConfig{
 			UpstreamTimeout: timeout,
 			FilteringConfig: FilteringConfig{
-				BlockingMode: BlockingModeDefault,
+				BlockingMode:     BlockingModeDefault,
+				EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
 			},
 		}
 
@@ -323,6 +330,9 @@ func TestServer_timeout(t *testing.T) {
 		require.NoError(t, err)
 
 		s.conf.FilteringConfig.BlockingMode = BlockingModeDefault
+		s.conf.FilteringConfig.EDNSClientSubnet = &EDNSClientSubnet{
+			Enabled: false,
+		}
 		err = s.Prepare(&s.conf)
 		require.NoError(t, err)
 
@@ -334,6 +344,9 @@ func TestServerWithProtectionDisabled(t *testing.T) {
 	s := createTestServer(t, &filtering.Config{}, ServerConfig{
 		UDPListenAddrs: []*net.UDPAddr{{}},
 		TCPListenAddrs: []*net.TCPAddr{{}},
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+		},
 	}, nil)
 	s.conf.UpstreamConfig.Upstreams = []upstream.Upstream{newGoogleUpstream()}
 	startDeferStop(t, s)
@@ -438,6 +451,9 @@ func TestSafeSearch(t *testing.T) {
 		TCPListenAddrs: []*net.TCPAddr{{}},
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, filterConf, forwardConf, nil)
@@ -493,6 +509,11 @@ func TestInvalidRequest(t *testing.T) {
 	s := createTestServer(t, &filtering.Config{}, ServerConfig{
 		UDPListenAddrs: []*net.UDPAddr{{}},
 		TCPListenAddrs: []*net.TCPAddr{{}},
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
+		},
 	}, nil)
 	startDeferStop(t, s)
 
@@ -519,6 +540,9 @@ func TestBlockedRequest(t *testing.T) {
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, &filtering.Config{}, forwardConf, nil)
@@ -544,6 +568,9 @@ func TestServerCustomClientUpstream(t *testing.T) {
 		TCPListenAddrs: []*net.TCPAddr{{}},
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, &filtering.Config{}, forwardConf, nil)
@@ -592,6 +619,11 @@ func TestBlockCNAMEProtectionEnabled(t *testing.T) {
 	s := createTestServer(t, &filtering.Config{}, ServerConfig{
 		UDPListenAddrs: []*net.UDPAddr{{}},
 		TCPListenAddrs: []*net.TCPAddr{{}},
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
+		},
 	}, nil)
 	testUpstm := &aghtest.Upstream{
 		CName: testCNAMEs,
@@ -622,6 +654,9 @@ func TestBlockCNAME(t *testing.T) {
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, &filtering.Config{}, forwardConf, nil)
@@ -691,6 +726,9 @@ func TestClientRulesForCNAMEMatching(t *testing.T) {
 			FilterHandler: func(_ net.IP, _ string, settings *filtering.Settings) {
 				settings.FilteringEnabled = false
 			},
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, &filtering.Config{}, forwardConf, nil)
@@ -732,6 +770,9 @@ func TestNullBlockedRequest(t *testing.T) {
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeNullIP,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, &filtering.Config{}, forwardConf, nil)
@@ -784,6 +825,9 @@ func TestBlockedCustomIP(t *testing.T) {
 			BlockingMode:      BlockingModeCustomIP,
 			BlockingIPv4:      nil,
 			UpstreamDNS:       []string{"8.8.8.8:53", "8.8.4.4:53"},
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 
@@ -832,6 +876,9 @@ func TestBlockedByHosts(t *testing.T) {
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 
@@ -865,6 +912,9 @@ func TestBlockedBySafeBrowsing(t *testing.T) {
 		FilteringConfig: FilteringConfig{
 			SafeBrowsingBlockHost: ans4.String(),
 			ProtectionEnabled:     true,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	s := createTestServer(t, filterConf, forwardConf, nil)
@@ -919,6 +969,9 @@ func TestRewrite(t *testing.T) {
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
 			UpstreamDNS:       []string{"8.8.8.8:53"},
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}))
 
@@ -1033,6 +1086,7 @@ func TestPTRResponseFromDHCPLeases(t *testing.T) {
 	s.conf.UpstreamDNS = []string{"127.0.0.1:53"}
 	s.conf.FilteringConfig.ProtectionEnabled = true
 	s.conf.FilteringConfig.BlockingMode = BlockingModeDefault
+	s.conf.FilteringConfig.EDNSClientSubnet = &EDNSClientSubnet{Enabled: false}
 
 	err = s.Prepare(&s.conf)
 	require.NoError(t, err)
@@ -1108,6 +1162,7 @@ func TestPTRResponseFromHosts(t *testing.T) {
 	s.conf.TCPListenAddrs = []*net.TCPAddr{{}}
 	s.conf.UpstreamDNS = []string{"127.0.0.1:53"}
 	s.conf.FilteringConfig.BlockingMode = BlockingModeDefault
+	s.conf.FilteringConfig.EDNSClientSubnet = &EDNSClientSubnet{Enabled: false}
 
 	err = s.Prepare(&s.conf)
 	require.NoError(t, err)

internal/dnsforward/filter_test.go

@@ -29,6 +29,9 @@ func TestHandleDNSRequest_filterDNSResponse(t *testing.T) {
 		FilteringConfig: FilteringConfig{
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
+			EDNSClientSubnet: &EDNSClientSubnet{
+				Enabled: false,
+			},
 		},
 	}
 	filters := []filtering.Filter{{

internal/dnsforward/http.go

@@ -57,7 +57,7 @@ func (s *Server) getDNSConfig() (c *jsonDNSConfig) {
 	blockingIPv4 := s.conf.BlockingIPv4
 	blockingIPv6 := s.conf.BlockingIPv6
 	ratelimit := s.conf.Ratelimit
-	enableEDNSClientSubnet := s.conf.EnableEDNSClientSubnet
+	enableEDNSClientSubnet := s.conf.EDNSClientSubnet.Enabled
 	enableDNSSEC := s.conf.EnableDNSSEC
 	aaaaDisabled := s.conf.AAAADisabled
 	cacheSize := s.conf.CacheSize
@@ -280,7 +280,7 @@ func (s *Server) setConfigRestartable(dc *jsonDNSConfig) (shouldRestart bool) {
 		setIfNotNil(&s.conf.LocalPTRResolvers, dc.LocalPTRUpstreams),
 		setIfNotNil(&s.conf.UpstreamDNSFileName, dc.UpstreamsFile),
 		setIfNotNil(&s.conf.BootstrapDNS, dc.Bootstraps),
-		setIfNotNil(&s.conf.EnableEDNSClientSubnet, dc.EDNSCSEnabled),
+		setIfNotNil(&s.conf.EDNSClientSubnet.Enabled, dc.EDNSCSEnabled),
 		setIfNotNil(&s.conf.CacheSize, dc.CacheSize),
 		setIfNotNil(&s.conf.CacheMinTTL, dc.CacheMinTTL),
 		setIfNotNil(&s.conf.CacheMaxTTL, dc.CacheMaxTTL),

internal/dnsforward/http_test.go

@@ -69,6 +69,7 @@ func TestDNSForwardHTTP_handleGetConfig(t *testing.T) {
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
 			UpstreamDNS:       []string{"8.8.8.8:53", "8.8.4.4:53"},
+			EDNSClientSubnet:  &EDNSClientSubnet{Enabled: false},
 		},
 		ConfigModified: func() {},
 	}
@@ -144,6 +145,7 @@ func TestDNSForwardHTTP_handleSetConfig(t *testing.T) {
 			ProtectionEnabled: true,
 			BlockingMode:      BlockingModeDefault,
 			UpstreamDNS:       []string{"8.8.8.8:53", "8.8.4.4:53"},
+			EDNSClientSubnet:  &EDNSClientSubnet{Enabled: false},
 		},
 		ConfigModified: func() {},
 	}
@@ -227,7 +229,10 @@ func TestDNSForwardHTTP_handleSetConfig(t *testing.T) {
 		require.True(t, ok)
 
 		t.Run(tc.name, func(t *testing.T) {
-			t.Cleanup(func() { s.conf = defaultConf })
+			t.Cleanup(func() {
+				s.conf = defaultConf
+				s.conf.FilteringConfig.EDNSClientSubnet.Enabled = false
+			})
 
 			rBody := io.NopCloser(bytes.NewReader(caseData.Req))
 			var r *http.Request
@@ -443,6 +448,9 @@ func TestServer_handleTestUpstreaDNS(t *testing.T) {
 		UDPListenAddrs:  []*net.UDPAddr{{}},
 		TCPListenAddrs:  []*net.TCPAddr{{}},
 		UpstreamTimeout: upsTimeout,
+		FilteringConfig: FilteringConfig{
+			EDNSClientSubnet: &EDNSClientSubnet{Enabled: false},
+		},
 	}, nil)
 	startDeferStop(t, srv)
 

internal/home/upgrade.go

@@ -22,7 +22,7 @@ import (
 )
 
 // currentSchemaVersion is the current schema version.
-const currentSchemaVersion = 16
+const currentSchemaVersion = 17
 
 // These aliases are provided for convenience.
 type (
@@ -89,6 +89,7 @@ func upgradeConfigSchema(oldVersion int, diskConf yobj) (err error) {
 		upgradeSchema13to14,
 		upgradeSchema14to15,
 		upgradeSchema15to16,
+		upgradeSchema16to17,
 	}
 
 	n := 0
@@ -892,19 +893,56 @@ func upgradeSchema15to16(diskConf yobj) (err error) {
 		"ignored":  []any{},
 	}
 
-	k := "statistics_interval"
+	const field = "statistics_interval"
-	v, has := dns[k]
+	v, has := dns[field]
 	if has {
 		stats["enabled"] = v != 0
 		stats["interval"] = v
 	}
-	delete(dns, k)
+	delete(dns, field)
 
 	diskConf["statistics"] = stats
 
 	return nil
 }
 
+// upgradeSchema16to17 performs the following changes:
+//
+//	# BEFORE:
+//	'dns':
+//	  'edns_client_subnet': false
+//
+//	# AFTER:
+//	'dns':
+//	  'edns_client_subnet':
+//	    'enabled': false
+//	    'use_custom': false
+//	    'custom_ip': ""
+func upgradeSchema16to17(diskConf yobj) (err error) {
+	log.Printf("Upgrade yaml: 16 to 17")
+	diskConf["schema_version"] = 17
+
+	dnsVal, ok := diskConf["dns"]
+	if !ok {
+		return nil
+	}
+
+	dns, ok := dnsVal.(yobj)
+	if !ok {
+		return fmt.Errorf("unexpected type of dns: %T", dnsVal)
+	}
+
+	const field = "edns_client_subnet"
+
+	dns[field] = map[string]any{
+		"enabled":    dns[field] == true,
+		"use_custom": false,
+		"custom_ip":  "",
+	}
+
+	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

@@ -747,3 +747,64 @@ func TestUpgradeSchema15to16(t *testing.T) {
 		})
 	}
 }
+
+func TestUpgradeSchema16to17(t *testing.T) {
+	const newSchemaVer = 17
+
+	defaultWantObj := yobj{
+		"dns": map[string]any{
+			"edns_client_subnet": map[string]any{
+				"enabled":    false,
+				"use_custom": false,
+				"custom_ip":  "",
+			},
+		},
+		"schema_version": newSchemaVer,
+	}
+
+	testCases := []struct {
+		in   yobj
+		want yobj
+		name string
+	}{{
+		in: yobj{
+			"dns": map[string]any{
+				"edns_client_subnet": false,
+			},
+		},
+		want: defaultWantObj,
+		name: "basic",
+	}, {
+		in: yobj{
+			"dns": map[string]any{},
+		},
+		want: defaultWantObj,
+		name: "default_values",
+	}, {
+		in: yobj{
+			"dns": map[string]any{
+				"edns_client_subnet": true,
+			},
+		},
+		want: yobj{
+			"dns": map[string]any{
+				"edns_client_subnet": map[string]any{
+					"enabled":    true,
+					"use_custom": false,
+					"custom_ip":  "",
+				},
+			},
+			"schema_version": newSchemaVer,
+		},
+		name: "is_true",
+	}}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			err := upgradeSchema16to17(tc.in)
+			require.NoError(t, err)
+
+			assert.Equal(t, tc.want, tc.in)
+		})
+	}
+}