Merge branch 'master' into 4927-refactor-tls

Updates #4927.

Squashed commit of the following:

commit 510143325805133e379ebc207cdc6bff59c94ade
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Nov 22 15:00:13 2022 +0300

    home: imp err

commit fd65a9914494b6dccdee7c0f0aa08bce80ce0945
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Nov 21 18:53:39 2022 +0300

    client: imp validation ui

CHANGELOG.md

@@ -25,6 +25,13 @@ See also the [v0.107.19 GitHub milestone][ms-v0.107.19].
 [ms-v0.107.19]: https://github.com/AdguardTeam/AdGuardHome/milestone/55?closed=1
 -->
 
+### Added
+
+- The new `--update` command-line option, which allows updating AdGuard Home
+  silently ([#4223]).
+
+[#4223]: https://github.com/AdguardTeam/AdGuardHome/issues/4223
+
 
 
 ## [v0.107.18] - 2022-11-08

Makefile

@@ -34,6 +34,8 @@ YARN_INSTALL_FLAGS = $(YARN_FLAGS) --network-timeout 120000 --silent\
 	--ignore-engines --ignore-optional --ignore-platform\
 	--ignore-scripts
 
+NEXTAPI = 0
+
 # Macros for the build-release target.  If FRONTEND_PREBUILT is 0, the
 # default, the macro $(BUILD_RELEASE_DEPS_$(FRONTEND_PREBUILT)) expands
 # into BUILD_RELEASE_DEPS_0, and so both frontend and backend
@@ -61,6 +63,7 @@ ENV = env\
 	PATH="$${PWD}/bin:$$( "$(GO.MACRO)" env GOPATH )/bin:$${PATH}"\
 	RACE='$(RACE)'\
 	SIGN='$(SIGN)'\
+	NEXTAPI='$(NEXTAPI)'\
 	VERBOSE='$(VERBOSE)'\
 	VERSION='$(VERSION)'\
 

client/src/__locales/en.json

@@ -393,6 +393,7 @@
     "encryption_issuer": "Issuer",
     "encryption_hostnames": "Hostnames",
     "encryption_reset": "Are you sure you want to reset encryption settings?",
+    "encryption_warning": "Warning",
     "topline_expiring_certificate": "Your SSL certificate is about to expire. Update <0>Encryption settings</0>.",
     "topline_expired_certificate": "Your SSL certificate is expired. Update <0>Encryption settings</0>.",
     "form_error_port_range": "Enter port number in the range of 80-65535",

client/src/components/Settings/Encryption/Form.js

@@ -56,6 +56,26 @@ const clearFields = (change, setTlsConfig, t) => {
     }
 };
 
+const validationMessage = (warningValidation, isWarning) => {
+    if (!warningValidation) {
+        return null;
+    }
+
+    if (isWarning) {
+        return (
+            <div className="col-12">
+                <p><Trans>encryption_warning</Trans>: {warningValidation}</p>
+            </div>
+        );
+    }
+
+    return (
+        <div className="col-12">
+            <p className="text-danger">{warningValidation}</p>
+        </div>
+    );
+};
+
 let Form = (props) => {
     const {
         t,
@@ -95,6 +115,8 @@ let Form = (props) => {
         || !valid_cert
         || !valid_pair;
 
+    const isWarning = valid_key && valid_cert && valid_pair;
+
     return (
         <form onSubmit={handleSubmit}>
             <div className="row">
@@ -382,11 +404,7 @@ let Form = (props) => {
                         )}
                     </div>
                 </div>
-                {warning_validation && (
-                    <div className="col-12">
-                        <p className="text-danger">{warning_validation}</p>
-                    </div>
-                )}
+                {validationMessage(warning_validation, isWarning)}
             </div>
 
             <div className="btn-list mt-2">

internal/aghnet/net.go

@@ -31,12 +31,6 @@ var (
 // the IP being static is available.
 const ErrNoStaticIPInfo errors.Error = "no information about static ip"
 
-// IPv4Localhost returns 127.0.0.1, which returns true for [netip.Addr.Is4].
-func IPv4Localhost() (ip netip.Addr) { return netip.AddrFrom4([4]byte{127, 0, 0, 1}) }
-
-// IPv6Localhost returns ::1, which returns true for [netip.Addr.Is6].
-func IPv6Localhost() (ip netip.Addr) { return netip.AddrFrom16([16]byte{15: 1}) }
-
 // IfaceHasStaticIP checks if interface is configured to have static IP address.
 // If it can't give a definitive answer, it returns false and an error for which
 // errors.Is(err, ErrNoStaticIPInfo) is true.

internal/aghnet/net_test.go

@@ -188,7 +188,7 @@ func TestBroadcastFromIPNet(t *testing.T) {
 }
 
 func TestCheckPort(t *testing.T) {
-	laddr := netip.AddrPortFrom(IPv4Localhost(), 0)
+	laddr := netip.AddrPortFrom(netutil.IPv4Localhost(), 0)
 
 	t.Run("tcp_bound", func(t *testing.T) {
 		l, err := net.Listen("tcp", laddr.String())

internal/aghtest/interface.go

@@ -1,10 +1,12 @@
 package aghtest
 
 import (
+	"context"
 	"io/fs"
 	"net"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghos"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
 	"github.com/AdguardTeam/dnsproxy/upstream"
 	"github.com/miekg/dns"
 )
@@ -116,6 +118,36 @@ func (w *FSWatcher) Close() (err error) {
 	return w.OnClose()
 }
 
+// Package agh
+
+// type check
+var _ agh.ServiceWithConfig[struct{}] = (*ServiceWithConfig[struct{}])(nil)
+
+// ServiceWithConfig is a mock [agh.ServiceWithConfig] implementation for tests.
+type ServiceWithConfig[ConfigType any] struct {
+	OnStart    func() (err error)
+	OnShutdown func(ctx context.Context) (err error)
+	OnConfig   func() (c ConfigType)
+}
+
+// Start implements the [agh.ServiceWithConfig] interface for
+// *ServiceWithConfig.
+func (s *ServiceWithConfig[_]) Start() (err error) {
+	return s.OnStart()
+}
+
+// Shutdown implements the [agh.ServiceWithConfig] interface for
+// *ServiceWithConfig.
+func (s *ServiceWithConfig[_]) Shutdown(ctx context.Context) (err error) {
+	return s.OnShutdown(ctx)
+}
+
+// Config implements the [agh.ServiceWithConfig] interface for
+// *ServiceWithConfig.
+func (s *ServiceWithConfig[ConfigType]) Config() (c ConfigType) {
+	return s.OnConfig()
+}
+
 // Module dnsproxy
 
 // Package upstream

internal/dnsforward/clientid.go

@@ -23,16 +23,6 @@ func ValidateClientID(id string) (err error) {
 	return nil
 }
 
-// hasLabelSuffix returns true if s ends with suffix preceded by a dot.  It's
-// a helper function to prevent unnecessary allocations in code like:
-//
-// if strings.HasSuffix(s, "." + suffix) { /* … */ }
-//
-// s must be longer than suffix.
-func hasLabelSuffix(s, suffix string) (ok bool) {
-	return strings.HasSuffix(s, suffix) && s[len(s)-len(suffix)-1] == '.'
-}
-
 // clientIDFromClientServerName extracts and validates a ClientID.  hostSrvName
 // is the server name of the host.  cliSrvName is the server name as sent by the
 // client.  When strict is true, and client and host server name don't match,
@@ -46,7 +36,7 @@ func clientIDFromClientServerName(
 		return "", nil
 	}
 
-	if !hasLabelSuffix(cliSrvName, hostSrvName) {
+	if !netutil.IsImmediateSubdomain(cliSrvName, hostSrvName) {
 		if !strict {
 			return "", nil
 		}

internal/dnsforward/config.go

@@ -145,7 +145,8 @@ type FilteringConfig struct {
 	IpsetListFileName string `yaml:"ipset_file"`
 }
 
-// TLSConfig is the TLS configuration for HTTPS, DNS-over-HTTPS, and DNS-over-TLS
+// TLSConfig is the TLS configuration for HTTPS, DNS-over-HTTPS, DNS-over-TLS,
+// and DNS-over-QUIC.
 type TLSConfig struct {
 	cert tls.Certificate
 

internal/dnsforward/dnsforward.go

@@ -246,6 +246,7 @@ type RDNSExchanger interface {
 	// Exchange tries to resolve the ip in a suitable way, e.g. either as
 	// local or as external.
 	Exchange(ip net.IP) (host string, err error)
+
 	// ResolvesPrivatePTR returns true if the RDNSExchanger is able to
 	// resolve PTR requests for locally-served addresses.
 	ResolvesPrivatePTR() (ok bool)
@@ -261,6 +262,9 @@ const (
 	rDNSNotPTRErr errors.Error = "the response is not a ptr"
 )
 
+// type check
+var _ RDNSExchanger = (*Server)(nil)
+
 // Exchange implements the RDNSExchanger interface for *Server.
 func (s *Server) Exchange(ip net.IP) (host string, err error) {
 	s.serverLock.RLock()
@@ -675,21 +679,13 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 // IsBlockedClient returns true if the client is blocked by the current access
 // settings.
-func (s *Server) IsBlockedClient(ip net.IP, clientID string) (blocked bool, rule string) {
+func (s *Server) IsBlockedClient(ip netip.Addr, clientID string) (blocked bool, rule string) {
 	s.serverLock.RLock()
 	defer s.serverLock.RUnlock()
 
 	blockedByIP := false
-	if ip != nil {
-		// TODO(a.garipov):  Remove once we switch to netip.Addr more fully.
-		ipAddr, err := netutil.IPToAddrNoMapped(ip)
-		if err != nil {
-			log.Error("dnsforward: bad client ip %v: %s", ip, err)
-
-			return false, ""
-		}
-
-		blockedByIP, rule = s.access.isBlockedIP(ipAddr)
+	if ip != (netip.Addr{}) {
+		blockedByIP, rule = s.access.isBlockedIP(ip)
 	}
 
 	allowlistMode := s.access.allowlistMode()

internal/dnsforward/filter.go

@@ -19,13 +19,13 @@ func (s *Server) beforeRequestHandler(
 	_ *proxy.Proxy,
 	pctx *proxy.DNSContext,
 ) (reply bool, err error) {
-	ip, _ := netutil.IPAndPortFromAddr(pctx.Addr)
 	clientID, err := s.clientIDFromDNSContext(pctx)
 	if err != nil {
 		return false, fmt.Errorf("getting clientid: %w", err)
 	}
 
-	blocked, _ := s.IsBlockedClient(ip, clientID)
+	addrPort := netutil.NetAddrToAddrPort(pctx.Addr)
+	blocked, _ := s.IsBlockedClient(addrPort.Addr(), clientID)
 	if blocked {
 		return s.preBlockedResponse(pctx)
 	}

internal/filtering/filter_test.go

@@ -11,7 +11,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
+	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/AdguardTeam/golibs/testutil"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -40,7 +40,7 @@ func serveFiltersLocally(t *testing.T, fltContent []byte) (ipp netip.AddrPort) {
 	addr := l.Addr()
 	require.IsType(t, new(net.TCPAddr), addr)
 
-	return netip.AddrPortFrom(aghnet.IPv4Localhost(), uint16(addr.(*net.TCPAddr).Port))
+	return netip.AddrPortFrom(netutil.IPv4Localhost(), uint16(addr.(*net.TCPAddr).Port))
 }
 
 func TestFilters(t *testing.T) {

internal/home/clients.go

@@ -129,7 +129,7 @@ type RuntimeClientWHOISInfo struct {
 
 type clientsContainer struct {
 	// TODO(a.garipov): Perhaps use a number of separate indices for
-	// different types (string, net.IP, and so on).
+	// different types (string, netip.Addr, and so on).
 	list    map[string]*Client // name -> client
 	idIndex map[string]*Client // ID -> client
 
@@ -333,7 +333,7 @@ func (clients *clientsContainer) onDHCPLeaseChanged(flags int) {
 }
 
 // exists checks if client with this IP address already exists.
-func (clients *clientsContainer) exists(ip net.IP, source clientSource) (ok bool) {
+func (clients *clientsContainer) exists(ip netip.Addr, source clientSource) (ok bool) {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
@@ -342,7 +342,7 @@ func (clients *clientsContainer) exists(ip net.IP, source clientSource) (ok bool
 		return true
 	}
 
-	rc, ok := clients.findRuntimeClientLocked(ip)
+	rc, ok := clients.ipToRC[ip]
 	if !ok {
 		return false
 	}
@@ -371,7 +371,8 @@ func (clients *clientsContainer) findMultiple(ids []string) (c *querylog.Client,
 	var artClient *querylog.Client
 	var art bool
 	for _, id := range ids {
-		c, art = clients.clientOrArtificial(net.ParseIP(id), id)
+		ip, _ := netip.ParseAddr(id)
+		c, art = clients.clientOrArtificial(ip, id)
 		if art {
 			artClient = c
 
@@ -389,7 +390,7 @@ func (clients *clientsContainer) findMultiple(ids []string) (c *querylog.Client,
 // records about this client besides maybe whether or not it is blocked.  c is
 // never nil.
 func (clients *clientsContainer) clientOrArtificial(
-	ip net.IP,
+	ip netip.Addr,
 	id string,
 ) (c *querylog.Client, art bool) {
 	defer func() {
@@ -406,13 +407,6 @@ func (clients *clientsContainer) clientOrArtificial(
 		}, false
 	}
 
-	if ip == nil {
-		// Technically should never happen, but still.
-		return &querylog.Client{
-			Name: "",
-		}, true
-	}
-
 	var rc *RuntimeClient
 	rc, ok = clients.findRuntimeClient(ip)
 	if ok {
@@ -492,19 +486,20 @@ func (clients *clientsContainer) findLocked(id string) (c *Client, ok bool) {
 		return c, true
 	}
 
-	ip := net.ParseIP(id)
-	if ip == nil {
+	ip, err := netip.ParseAddr(id)
+	if err != nil {
 		return nil, false
 	}
 
 	for _, c = range clients.list {
 		for _, id := range c.IDs {
-			_, ipnet, err := net.ParseCIDR(id)
+			var n netip.Prefix
+			n, err = netip.ParsePrefix(id)
 			if err != nil {
 				continue
 			}
 
-			if ipnet.Contains(ip) {
+			if n.Contains(ip) {
 				return c, true
 			}
 		}
@@ -514,19 +509,20 @@ func (clients *clientsContainer) findLocked(id string) (c *Client, ok bool) {
 		return nil, false
 	}
 
-	macFound := clients.dhcpServer.FindMACbyIP(ip)
+	macFound := clients.dhcpServer.FindMACbyIP(ip.AsSlice())
 	if macFound == nil {
 		return nil, false
 	}
 
 	for _, c = range clients.list {
 		for _, id := range c.IDs {
-			hwAddr, err := net.ParseMAC(id)
+			var mac net.HardwareAddr
+			mac, err = net.ParseMAC(id)
 			if err != nil {
 				continue
 			}
 
-			if bytes.Equal(hwAddr, macFound) {
+			if bytes.Equal(mac, macFound) {
 				return c, true
 			}
 		}
@@ -535,32 +531,18 @@ func (clients *clientsContainer) findLocked(id string) (c *Client, ok bool) {
 	return nil, false
 }
 
-// findRuntimeClientLocked finds a runtime client by their IP address.  For
-// internal use only.
-func (clients *clientsContainer) findRuntimeClientLocked(ip net.IP) (rc *RuntimeClient, ok bool) {
-	// TODO(a.garipov):  Remove once we switch to netip.Addr more fully.
-	ipAddr, err := netutil.IPToAddrNoMapped(ip)
-	if err != nil {
-		log.Error("clients: bad client ip %v: %s", ip, err)
-
-		return nil, false
-	}
-
-	rc, ok = clients.ipToRC[ipAddr]
-
-	return rc, ok
-}
-
 // findRuntimeClient finds a runtime client by their IP.
-func (clients *clientsContainer) findRuntimeClient(ip net.IP) (rc *RuntimeClient, ok bool) {
-	if ip == nil {
+func (clients *clientsContainer) findRuntimeClient(ip netip.Addr) (rc *RuntimeClient, ok bool) {
+	if ip == (netip.Addr{}) {
 		return nil, false
 	}
 
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
-	return clients.findRuntimeClientLocked(ip)
+	rc, ok = clients.ipToRC[ip]
+
+	return rc, ok
 }
 
 // check validates the client.
@@ -578,14 +560,16 @@ func (clients *clientsContainer) check(c *Client) (err error) {
 
 	for i, id := range c.IDs {
 		// Normalize structured data.
-		var ip net.IP
-		var ipnet *net.IPNet
-		var mac net.HardwareAddr
-		if ip = net.ParseIP(id); ip != nil {
+		var (
+			ip  netip.Addr
+			n   netip.Prefix
+			mac net.HardwareAddr
+		)
+
+		if ip, err = netip.ParseAddr(id); err == nil {
 			c.IDs[i] = ip.String()
-		} else if ip, ipnet, err = net.ParseCIDR(id); err == nil {
-			ipnet.IP = ip
-			c.IDs[i] = ipnet.String()
+		} else if n, err = netip.ParsePrefix(id); err == nil {
+			c.IDs[i] = n.String()
 		} else if mac, err = net.ParseMAC(id); err == nil {
 			c.IDs[i] = mac.String()
 		} else if err = dnsforward.ValidateClientID(id); err == nil {
@@ -750,7 +734,7 @@ func (clients *clientsContainer) Update(name string, c *Client) (err error) {
 }
 
 // setWHOISInfo sets the WHOIS information for a client.
-func (clients *clientsContainer) setWHOISInfo(ip net.IP, wi *RuntimeClientWHOISInfo) {
+func (clients *clientsContainer) setWHOISInfo(ip netip.Addr, wi *RuntimeClientWHOISInfo) {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
@@ -760,7 +744,7 @@ func (clients *clientsContainer) setWHOISInfo(ip net.IP, wi *RuntimeClientWHOISI
 		return
 	}
 
-	rc, ok := clients.findRuntimeClientLocked(ip)
+	rc, ok := clients.ipToRC[ip]
 	if ok {
 		rc.WHOISInfo = wi
 		log.Debug("clients: set whois info for runtime client %s: %+v", rc.Host, wi)
@@ -776,32 +760,22 @@ func (clients *clientsContainer) setWHOISInfo(ip net.IP, wi *RuntimeClientWHOISI
 
 	rc.WHOISInfo = wi
 
-	// TODO(a.garipov):  Remove once we switch to netip.Addr more fully.
-	ipAddr, err := netutil.IPToAddrNoMapped(ip)
-	if err != nil {
-		log.Error("clients: bad client ip %v: %s", ip, err)
-
-		return
-	}
-
-	clients.ipToRC[ipAddr] = rc
+	clients.ipToRC[ip] = rc
 
 	log.Debug("clients: set whois info for runtime client with ip %s: %+v", ip, wi)
 }
 
 // AddHost adds a new IP-hostname pairing.  The priorities of the sources are
 // taken into account.  ok is true if the pairing was added.
-func (clients *clientsContainer) AddHost(ip net.IP, host string, src clientSource) (ok bool, err error) {
+func (clients *clientsContainer) AddHost(
+	ip netip.Addr,
+	host string,
+	src clientSource,
+) (ok bool) {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
-	// TODO(a.garipov):  Remove once we switch to netip.Addr more fully.
-	ipAddr, err := netutil.IPToAddrNoMapped(ip)
-	if err != nil {
-		return false, fmt.Errorf("adding host: %w", err)
-	}
-
-	return clients.addHostLocked(ipAddr, host, src), nil
+	return clients.addHostLocked(ip, host, src)
 }
 
 // addHostLocked adds a new IP-hostname pairing.  clients.lock is expected to be

internal/home/clients_test.go

@@ -22,8 +22,18 @@ func TestClients(t *testing.T) {
 	clients.Init(nil, nil, nil, nil)
 
 	t.Run("add_success", func(t *testing.T) {
+		var (
+			cliNone = "1.2.3.4"
+			cli1    = "1.1.1.1"
+			cli2    = "2.2.2.2"
+
+			cliNoneIP = netip.MustParseAddr(cliNone)
+			cli1IP    = netip.MustParseAddr(cli1)
+			cli2IP    = netip.MustParseAddr(cli2)
+		)
+
 		c := &Client{
-			IDs:  []string{"1.1.1.1", "1:2:3::4", "aa:aa:aa:aa:aa:aa"},
+			IDs:  []string{cli1, "1:2:3::4", "aa:aa:aa:aa:aa:aa"},
 			Name: "client1",
 		}
 
@@ -33,7 +43,7 @@ func TestClients(t *testing.T) {
 		assert.True(t, ok)
 
 		c = &Client{
-			IDs:  []string{"2.2.2.2"},
+			IDs:  []string{cli2},
 			Name: "client2",
 		}
 
@@ -42,7 +52,7 @@ func TestClients(t *testing.T) {
 
 		assert.True(t, ok)
 
-		c, ok = clients.Find("1.1.1.1")
+		c, ok = clients.Find(cli1)
 		require.True(t, ok)
 
 		assert.Equal(t, "client1", c.Name)
@@ -52,14 +62,14 @@ func TestClients(t *testing.T) {
 
 		assert.Equal(t, "client1", c.Name)
 
-		c, ok = clients.Find("2.2.2.2")
+		c, ok = clients.Find(cli2)
 		require.True(t, ok)
 
 		assert.Equal(t, "client2", c.Name)
 
-		assert.False(t, clients.exists(net.IP{1, 2, 3, 4}, ClientSourceHostsFile))
-		assert.True(t, clients.exists(net.IP{1, 1, 1, 1}, ClientSourceHostsFile))
-		assert.True(t, clients.exists(net.IP{2, 2, 2, 2}, ClientSourceHostsFile))
+		assert.False(t, clients.exists(cliNoneIP, ClientSourceHostsFile))
+		assert.True(t, clients.exists(cli1IP, ClientSourceHostsFile))
+		assert.True(t, clients.exists(cli2IP, ClientSourceHostsFile))
 	})
 
 	t.Run("add_fail_name", func(t *testing.T) {
@@ -103,23 +113,31 @@ func TestClients(t *testing.T) {
 	})
 
 	t.Run("update_success", func(t *testing.T) {
+		var (
+			cliOld = "1.1.1.1"
+			cliNew = "1.1.1.2"
+
+			cliOldIP = netip.MustParseAddr(cliOld)
+			cliNewIP = netip.MustParseAddr(cliNew)
+		)
+
 		err := clients.Update("client1", &Client{
-			IDs:  []string{"1.1.1.2"},
+			IDs:  []string{cliNew},
 			Name: "client1",
 		})
 		require.NoError(t, err)
 
-		assert.False(t, clients.exists(net.IP{1, 1, 1, 1}, ClientSourceHostsFile))
-		assert.True(t, clients.exists(net.IP{1, 1, 1, 2}, ClientSourceHostsFile))
+		assert.False(t, clients.exists(cliOldIP, ClientSourceHostsFile))
+		assert.True(t, clients.exists(cliNewIP, ClientSourceHostsFile))
 
 		err = clients.Update("client1", &Client{
-			IDs:            []string{"1.1.1.2"},
+			IDs:            []string{cliNew},
 			Name:           "client1-renamed",
 			UseOwnSettings: true,
 		})
 		require.NoError(t, err)
 
-		c, ok := clients.Find("1.1.1.2")
+		c, ok := clients.Find(cliNew)
 		require.True(t, ok)
 
 		assert.Equal(t, "client1-renamed", c.Name)
@@ -132,14 +150,14 @@ func TestClients(t *testing.T) {
 
 		require.Len(t, c.IDs, 1)
 
-		assert.Equal(t, "1.1.1.2", c.IDs[0])
+		assert.Equal(t, cliNew, c.IDs[0])
 	})
 
 	t.Run("del_success", func(t *testing.T) {
 		ok := clients.Del("client1-renamed")
 		require.True(t, ok)
 
-		assert.False(t, clients.exists(net.IP{1, 1, 1, 2}, ClientSourceHostsFile))
+		assert.False(t, clients.exists(netip.MustParseAddr("1.1.1.2"), ClientSourceHostsFile))
 	})
 
 	t.Run("del_fail", func(t *testing.T) {
@@ -148,45 +166,33 @@ func TestClients(t *testing.T) {
 	})
 
 	t.Run("addhost_success", func(t *testing.T) {
-		ip := net.IP{1, 1, 1, 1}
-
-		ok, err := clients.AddHost(ip, "host", ClientSourceARP)
-		require.NoError(t, err)
-
+		ip := netip.MustParseAddr("1.1.1.1")
+		ok := clients.AddHost(ip, "host", ClientSourceARP)
 		assert.True(t, ok)
 
-		ok, err = clients.AddHost(ip, "host2", ClientSourceARP)
-		require.NoError(t, err)
-
+		ok = clients.AddHost(ip, "host2", ClientSourceARP)
 		assert.True(t, ok)
 
-		ok, err = clients.AddHost(ip, "host3", ClientSourceHostsFile)
-		require.NoError(t, err)
-
+		ok = clients.AddHost(ip, "host3", ClientSourceHostsFile)
 		assert.True(t, ok)
 
 		assert.True(t, clients.exists(ip, ClientSourceHostsFile))
 	})
 
 	t.Run("dhcp_replaces_arp", func(t *testing.T) {
-		ip := net.IP{1, 2, 3, 4}
-
-		ok, err := clients.AddHost(ip, "from_arp", ClientSourceARP)
-		require.NoError(t, err)
-
+		ip := netip.MustParseAddr("1.2.3.4")
+		ok := clients.AddHost(ip, "from_arp", ClientSourceARP)
 		assert.True(t, ok)
 		assert.True(t, clients.exists(ip, ClientSourceARP))
 
-		ok, err = clients.AddHost(ip, "from_dhcp", ClientSourceDHCP)
-		require.NoError(t, err)
-
+		ok = clients.AddHost(ip, "from_dhcp", ClientSourceDHCP)
 		assert.True(t, ok)
 		assert.True(t, clients.exists(ip, ClientSourceDHCP))
 	})
 
 	t.Run("addhost_fail", func(t *testing.T) {
-		ok, err := clients.AddHost(net.IP{1, 1, 1, 1}, "host1", ClientSourceRDNS)
-		require.NoError(t, err)
+		ip := netip.MustParseAddr("1.1.1.1")
+		ok := clients.AddHost(ip, "host1", ClientSourceRDNS)
 		assert.False(t, ok)
 	})
 }
@@ -203,7 +209,7 @@ func TestClientsWHOIS(t *testing.T) {
 
 	t.Run("new_client", func(t *testing.T) {
 		ip := netip.MustParseAddr("1.1.1.255")
-		clients.setWHOISInfo(ip.AsSlice(), whois)
+		clients.setWHOISInfo(ip, whois)
 		rc := clients.ipToRC[ip]
 		require.NotNil(t, rc)
 
@@ -212,12 +218,10 @@ func TestClientsWHOIS(t *testing.T) {
 
 	t.Run("existing_auto-client", func(t *testing.T) {
 		ip := netip.MustParseAddr("1.1.1.1")
-		ok, err := clients.AddHost(ip.AsSlice(), "host", ClientSourceRDNS)
-		require.NoError(t, err)
-
+		ok := clients.AddHost(ip, "host", ClientSourceRDNS)
 		assert.True(t, ok)
 
-		clients.setWHOISInfo(ip.AsSlice(), whois)
+		clients.setWHOISInfo(ip, whois)
 		rc := clients.ipToRC[ip]
 		require.NotNil(t, rc)
 
@@ -234,7 +238,7 @@ func TestClientsWHOIS(t *testing.T) {
 		require.NoError(t, err)
 		assert.True(t, ok)
 
-		clients.setWHOISInfo(ip.AsSlice(), whois)
+		clients.setWHOISInfo(ip, whois)
 		rc := clients.ipToRC[ip]
 		require.Nil(t, rc)
 
@@ -249,7 +253,7 @@ func TestClientsAddExisting(t *testing.T) {
 	clients.Init(nil, nil, nil, nil)
 
 	t.Run("simple", func(t *testing.T) {
-		ip := net.IP{1, 1, 1, 1}
+		ip := netip.MustParseAddr("1.1.1.1")
 
 		// Add a client.
 		ok, err := clients.Add(&Client{
@@ -260,8 +264,7 @@ func TestClientsAddExisting(t *testing.T) {
 		assert.True(t, ok)
 
 		// Now add an auto-client with the same IP.
-		ok, err = clients.AddHost(ip, "test", ClientSourceRDNS)
-		require.NoError(t, err)
+		ok = clients.AddHost(ip, "test", ClientSourceRDNS)
 		assert.True(t, ok)
 	})
 

internal/home/clientshttp.go

@@ -3,8 +3,8 @@ package home
 import (
 	"encoding/json"
 	"fmt"
-	"net"
 	"net/http"
+	"net/netip"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
 )
@@ -47,8 +47,8 @@ type runtimeClientJSON struct {
 	WHOISInfo *RuntimeClientWHOISInfo `json:"whois_info"`
 
 	Name   string       `json:"name"`
+	IP     netip.Addr   `json:"ip"`
 	Source clientSource `json:"source"`
-	IP     net.IP       `json:"ip"`
 }
 
 type clientListJSON struct {
@@ -75,7 +75,7 @@ func (clients *clientsContainer) handleGetClients(w http.ResponseWriter, r *http
 
 			Name:   rc.Host,
 			Source: rc.Source,
-			IP:     ip.AsSlice(),
+			IP:     ip,
 		}
 
 		data.RuntimeClients = append(data.RuntimeClients, cj)
@@ -218,7 +218,7 @@ func (clients *clientsContainer) handleFindClient(w http.ResponseWriter, r *http
 			break
 		}
 
-		ip := net.ParseIP(idStr)
+		ip, _ := netip.ParseAddr(idStr)
 		c, ok := clients.Find(idStr)
 		var cj *clientJSON
 		if !ok {
@@ -240,7 +240,7 @@ func (clients *clientsContainer) handleFindClient(w http.ResponseWriter, r *http
 // findRuntime looks up the IP in runtime and temporary storages, like
 // /etc/hosts tables, DHCP leases, or blocklists.  cj is guaranteed to be
 // non-nil.
-func (clients *clientsContainer) findRuntime(ip net.IP, idStr string) (cj *clientJSON) {
+func (clients *clientsContainer) findRuntime(ip netip.Addr, idStr string) (cj *clientJSON) {
 	rc, ok := clients.findRuntimeClient(ip)
 	if !ok {
 		// It is still possible that the IP used to be in the runtime clients

internal/home/config.go

@@ -20,6 +20,7 @@ import (
 	"github.com/AdguardTeam/golibs/log"
 	"github.com/AdguardTeam/golibs/timeutil"
 	"github.com/google/renameio/maybe"
+	"golang.org/x/exp/slices"
 	yaml "gopkg.in/yaml.v3"
 )
 
@@ -113,8 +114,8 @@ type configuration struct {
 	// An active session is automatically refreshed once a day.
 	WebSessionTTLHours uint32 `yaml:"web_session_ttl"`
 
-	DNS dnsConfig         `yaml:"dns"`
-	TLS tlsConfigSettings `yaml:"tls"`
+	DNS dnsConfig        `yaml:"dns"`
+	TLS tlsConfiguration `yaml:"tls"`
 
 	// Filters reflects the filters from [filtering.Config].  It's cloned to the
 	// config used in the filtering module at the startup.  Afterwards it's
@@ -199,7 +200,8 @@ type dnsConfig struct {
 	UseHTTP3Upstreams bool `yaml:"use_http3_upstreams"`
 }
 
-type tlsConfigSettings struct {
+// tlsConfiguration is the on-disk TLS configuration.
+type tlsConfiguration struct {
 	Enabled         bool   `yaml:"enabled" json:"enabled"`                                 // Enabled is the encryption (DoT/DoH/HTTPS) status
 	ServerName      string `yaml:"server_name" json:"server_name,omitempty"`               // ServerName is the hostname of your HTTPS/TLS server
 	ForceHTTPS      bool   `yaml:"force_https" json:"force_https"`                         // ForceHTTPS: if true, forces HTTP->HTTPS redirect
@@ -223,6 +225,29 @@ type tlsConfigSettings struct {
 	dnsforward.TLSConfig `yaml:",inline" json:",inline"`
 }
 
+// cloneForEncoding returns a clone of c with all top-level fields of c and all
+// exported and YAML-encoded fields of c.TLSConfig cloned.
+//
+// TODO(a.garipov): This is better than races, but still not good enough.
+func (c *tlsConfiguration) cloneForEncoding() (cloned *tlsConfiguration) {
+	if c == nil {
+		return nil
+	}
+
+	v := *c
+	cloned = &v
+	cloned.TLSConfig = dnsforward.TLSConfig{
+		CertificateChain:   c.CertificateChain,
+		PrivateKey:         c.PrivateKey,
+		CertificatePath:    c.CertificatePath,
+		PrivateKeyPath:     c.PrivateKeyPath,
+		OverrideTLSCiphers: slices.Clone(c.OverrideTLSCiphers),
+		StrictSNICheck:     c.StrictSNICheck,
+	}
+
+	return cloned
+}
+
 // config is the global configuration structure.
 //
 // TODO(a.garipov, e.burkov): This global is awful and must be removed.
@@ -273,7 +298,7 @@ var config = &configuration{
 		UpstreamTimeout: timeutil.Duration{Duration: dnsforward.DefaultTimeout},
 		UsePrivateRDNS:  true,
 	},
-	TLS: tlsConfigSettings{
+	TLS: tlsConfiguration{
 		PortHTTPS:       defaultPortHTTPS,
 		PortDNSOverTLS:  defaultPortTLS, // needs to be passed through to dnsproxy
 		PortDNSOverQUIC: defaultPortQUIC,
@@ -442,7 +467,7 @@ func (c *configuration) write() (err error) {
 	}
 
 	if Context.tls != nil {
-		tlsConf := tlsConfigSettings{}
+		tlsConf := tlsConfiguration{}
 		Context.tls.WriteDiskConfig(&tlsConf)
 		config.TLS = tlsConf
 	}

internal/home/control.go

@@ -71,9 +71,7 @@ func appendDNSAddrsWithIfaces(dst []string, src []netip.Addr) (res []string, err
 // on, including the addresses on all interfaces in cases of unspecified IPs.
 func collectDNSAddresses() (addrs []string, err error) {
 	if hosts := config.DNS.BindHosts; len(hosts) == 0 {
-		addr := aghnet.IPv4Localhost()
-
-		addrs = appendDNSAddrs(addrs, addr)
+		addrs = appendDNSAddrs(addrs, netutil.IPv4Localhost())
 	} else {
 		addrs, err = appendDNSAddrsWithIfaces(addrs, hosts)
 		if err != nil {

internal/home/controlupdate.go

@@ -154,7 +154,7 @@ func (vr *versionResponse) setAllowedToAutoUpdate() (err error) {
 		return nil
 	}
 
-	tlsConf := &tlsConfigSettings{}
+	tlsConf := &tlsConfiguration{}
 	Context.tls.WriteDiskConfig(tlsConf)
 
 	canUpdate := true
@@ -172,7 +172,7 @@ func (vr *versionResponse) setAllowedToAutoUpdate() (err error) {
 
 // tlsConfUsesPrivilegedPorts returns true if the provided TLS configuration
 // indicates that privileged ports are used.
-func tlsConfUsesPrivilegedPorts(c *tlsConfigSettings) (ok bool) {
+func tlsConfUsesPrivilegedPorts(c *tlsConfiguration) (ok bool) {
 	return c.Enabled && (c.PortHTTPS < 1024 || c.PortDNSOverTLS < 1024 || c.PortDNSOverQUIC < 1024)
 }
 

internal/home/dns.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 
+	"github.com/AdguardTeam/AdGuardHome/internal/aghalg"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
 	"github.com/AdguardTeam/AdGuardHome/internal/dnsforward"
 	"github.com/AdguardTeam/AdGuardHome/internal/filtering"
@@ -150,8 +151,8 @@ func isRunning() bool {
 }
 
 func onDNSRequest(pctx *proxy.DNSContext) {
-	ip, _ := netutil.IPAndPortFromAddr(pctx.Addr)
-	if ip == nil {
+	ip := netutil.NetAddrToAddrPort(pctx.Addr).Addr()
+	if ip == (netip.Addr{}) {
 		// This would be quite weird if we get here.
 		return
 	}
@@ -160,7 +161,8 @@ func onDNSRequest(pctx *proxy.DNSContext) {
 	if srcs.RDNS && !ip.IsLoopback() {
 		Context.rdns.Begin(ip)
 	}
-	if srcs.WHOIS && !netutil.IsSpecialPurpose(ip) {
+
+	if srcs.WHOIS && !netutil.IsSpecialPurposeAddr(ip) {
 		Context.whois.Begin(ip)
 	}
 }
@@ -193,11 +195,7 @@ func ipsToUDPAddrs(ips []netip.Addr, port int) (udpAddrs []*net.UDPAddr) {
 
 func generateServerConfig() (newConf dnsforward.ServerConfig, err error) {
 	dnsConf := config.DNS
-	hosts := dnsConf.BindHosts
-	if len(hosts) == 0 {
-		hosts = []netip.Addr{aghnet.IPv4Localhost()}
-	}
-
+	hosts := aghalg.CoalesceSlice(dnsConf.BindHosts, []netip.Addr{netutil.IPv4Localhost()})
 	newConf = dnsforward.ServerConfig{
 		UDPListenAddrs:  ipsToUDPAddrs(hosts, dnsConf.Port),
 		TCPListenAddrs:  ipsToTCPAddrs(hosts, dnsConf.Port),
@@ -207,7 +205,7 @@ func generateServerConfig() (newConf dnsforward.ServerConfig, err error) {
 		OnDNSRequest:    onDNSRequest,
 	}
 
-	tlsConf := tlsConfigSettings{}
+	tlsConf := tlsConfiguration{}
 	Context.tls.WriteDiskConfig(&tlsConf)
 	if tlsConf.Enabled {
 		newConf.TLSConfig = tlsConf.TLSConfig
@@ -252,7 +250,7 @@ func generateServerConfig() (newConf dnsforward.ServerConfig, err error) {
 	return newConf, nil
 }
 
-func newDNSCrypt(hosts []netip.Addr, tlsConf tlsConfigSettings) (dnscc dnsforward.DNSCryptConfig, err error) {
+func newDNSCrypt(hosts []netip.Addr, tlsConf tlsConfiguration) (dnscc dnsforward.DNSCryptConfig, err error) {
 	if tlsConf.DNSCryptConfigFile == "" {
 		return dnscc, errors.Error("no dnscrypt_config_file")
 	}
@@ -290,7 +288,7 @@ type dnsEncryption struct {
 }
 
 func getDNSEncryption() (de dnsEncryption) {
-	tlsConf := tlsConfigSettings{}
+	tlsConf := tlsConfiguration{}
 
 	Context.tls.WriteDiskConfig(&tlsConf)
 
@@ -400,15 +398,12 @@ func startDNSServer() error {
 
 	const topClientsNumber = 100 // the number of clients to get
 	for _, ip := range Context.stats.TopClientsIP(topClientsNumber) {
-		if ip == nil {
-			continue
-		}
-
 		srcs := config.Clients.Sources
 		if srcs.RDNS && !ip.IsLoopback() {
 			Context.rdns.Begin(ip)
 		}
-		if srcs.WHOIS && !netutil.IsSpecialPurpose(ip) {
+
+		if srcs.WHOIS && !netutil.IsSpecialPurposeAddr(ip) {
 			Context.whois.Begin(ip)
 		}
 	}

internal/home/home.go

@@ -512,7 +512,7 @@ func run(opts options, clientBuildFS fs.FS) {
 	}
 	config.Users = nil
 
-	Context.tls, err = newTLSManager(config.TLS)
+	Context.tls, err = newTLSManager(&config.TLS)
 	if err != nil {
 		log.Fatalf("initializing tls: %s", err)
 	}
@@ -542,6 +542,11 @@ func run(opts options, clientBuildFS fs.FS) {
 		}
 	}
 
+	// TODO(a.garipov): This could be made much earlier and could be done on
+	// the first run as well, but to achieve this we need to bypass requests
+	// over dnsforward resolver.
+	cmdlineUpdate(opts)
+
 	Context.web.Start()
 
 	// wait indefinitely for other go-routines to complete their job
@@ -576,7 +581,7 @@ func checkPermissions() {
 	}
 
 	// We should check if AdGuard Home is able to bind to port 53
-	err := aghnet.CheckPort("tcp", netip.AddrPortFrom(aghnet.IPv4Localhost(), defaultPortDNS))
+	err := aghnet.CheckPort("tcp", netip.AddrPortFrom(netutil.IPv4Localhost(), defaultPortDNS))
 	if err != nil {
 		if errors.Is(err, os.ErrPermission) {
 			log.Fatal(`Permission check failed.
@@ -812,7 +817,7 @@ func printWebAddrs(proto, addr string, port, betaPort int) {
 // printHTTPAddresses prints the IP addresses which user can use to access the
 // admin interface.  proto is either schemeHTTP or schemeHTTPS.
 func printHTTPAddresses(proto string) {
-	tlsConf := tlsConfigSettings{}
+	tlsConf := tlsConfiguration{}
 	if Context.tls != nil {
 		Context.tls.WriteDiskConfig(&tlsConf)
 	}
@@ -927,3 +932,37 @@ type jsonError struct {
 	// Message is the error message, an opaque string.
 	Message string `json:"message"`
 }
+
+// cmdlineUpdate updates current application and exits.
+func cmdlineUpdate(opts options) {
+	if !opts.performUpdate {
+		return
+	}
+
+	log.Info("starting update")
+
+	if Context.firstRun {
+		log.Info("update not allowed on first run")
+
+		os.Exit(0)
+	}
+
+	_, err := Context.updater.VersionInfo(true)
+	if err != nil {
+		vcu := Context.updater.VersionCheckURL()
+		log.Error("getting version info from %s: %s", vcu, err)
+
+		os.Exit(0)
+	}
+
+	if Context.updater.NewVersion() == "" {
+		log.Info("no updates available")
+
+		os.Exit(0)
+	}
+
+	err = Context.updater.Update()
+	fatalOnError(err)
+
+	os.Exit(0)
+}

internal/home/mobileconfig_test.go

@@ -32,7 +32,11 @@ func setupDNSIPs(t testing.TB) {
 		},
 	}
 
-	Context.tls = &tlsManager{}
+	var err error
+	Context.tls, err = newTLSManager(&tlsConfiguration{
+		Enabled: true,
+	})
+	require.NoError(t, err)
 }
 
 func TestHandleMobileConfigDoH(t *testing.T) {
@@ -65,7 +69,11 @@ func TestHandleMobileConfigDoH(t *testing.T) {
 		oldTLSConf := Context.tls
 		t.Cleanup(func() { Context.tls = oldTLSConf })
 
-		Context.tls = &tlsManager{conf: tlsConfigSettings{}}
+		var err error
+		Context.tls, err = newTLSManager(&tlsConfiguration{
+			Enabled: true,
+		})
+		require.NoError(t, err)
 
 		r, err := http.NewRequest(http.MethodGet, "https://example.com:12345/apple/doh.mobileconfig", nil)
 		require.NoError(t, err)
@@ -137,7 +145,11 @@ func TestHandleMobileConfigDoT(t *testing.T) {
 		oldTLSConf := Context.tls
 		t.Cleanup(func() { Context.tls = oldTLSConf })
 
-		Context.tls = &tlsManager{conf: tlsConfigSettings{}}
+		var err error
+		Context.tls, err = newTLSManager(&tlsConfiguration{
+			Enabled: true,
+		})
+		require.NoError(t, err)
 
 		r, err := http.NewRequest(http.MethodGet, "https://example.com:12345/apple/dot.mobileconfig", nil)
 		require.NoError(t, err)

internal/home/options.go

@@ -47,6 +47,9 @@ type options struct {
 	// disableUpdate, if set, makes AdGuard Home not check for updates.
 	disableUpdate bool
 
+	// performUpdate, if set, updates AdGuard Home without GUI and exits.
+	performUpdate bool
+
 	// verbose shows if verbose logging is enabled.
 	verbose bool
 
@@ -221,6 +224,14 @@ var cmdLineOpts = []cmdLineOpt{{
 	description:     "Don't check for updates.",
 	longName:        "no-check-update",
 	shortName:       "",
+}, {
+	updateWithValue: nil,
+	updateNoValue:   func(o options) (options, error) { o.performUpdate = true; return o, nil },
+	effect:          nil,
+	serialize:       func(o options) (val string, ok bool) { return "", o.performUpdate },
+	description:     "Update application and exit.",
+	longName:        "update",
+	shortName:       "",
 }, {
 	updateWithValue: nil,
 	updateNoValue:   nil,

internal/home/options_test.go

@@ -103,6 +103,11 @@ func TestParseDisableUpdate(t *testing.T) {
 	assert.True(t, testParseOK(t, "--no-check-update").disableUpdate, "--no-check-update is disable update")
 }
 
+func TestParsePerformUpdate(t *testing.T) {
+	assert.False(t, testParseOK(t).performUpdate, "empty is not perform update")
+	assert.True(t, testParseOK(t, "--update").performUpdate, "--update is perform update")
+}
+
 // TODO(e.burkov):  Remove after v0.108.0.
 func TestParseDisableMemoryOptimization(t *testing.T) {
 	o, eff, err := parseCmdOpts("", []string{"--no-mem-optimization"})
@@ -169,6 +174,10 @@ func TestOptsToArgs(t *testing.T) {
 		name: "disable_update",
 		args: []string{"--no-check-update"},
 		opts: options{disableUpdate: true},
+	}, {
+		name: "perform_update",
+		args: []string{"--update"},
+		opts: options{performUpdate: true},
 	}, {
 		name: "control_action",
 		args: []string{"-s", "run"},

internal/home/rdns.go

@@ -2,7 +2,7 @@ package home
 
 import (
 	"encoding/binary"
-	"net"
+	"net/netip"
 	"sync/atomic"
 	"time"
 
@@ -21,7 +21,7 @@ type RDNS struct {
 	usePrivate uint32
 
 	// ipCh used to pass client's IP to rDNS workerLoop.
-	ipCh chan net.IP
+	ipCh chan netip.Addr
 
 	// ipCache caches the IP addresses to be resolved by rDNS.  The resolved
 	// address stays here while it's inside clients.  After leaving clients the
@@ -50,7 +50,7 @@ func NewRDNS(
 			EnableLRU: true,
 			MaxCount:  defaultRDNSCacheSize,
 		}),
-		ipCh: make(chan net.IP, defaultRDNSIPChSize),
+		ipCh: make(chan netip.Addr, defaultRDNSIPChSize),
 	}
 	if usePrivate {
 		rDNS.usePrivate = 1
@@ -80,9 +80,10 @@ func (r *RDNS) ensurePrivateCache() {
 
 // isCached returns true if ip is already cached and not expired yet.  It also
 // caches it otherwise.
-func (r *RDNS) isCached(ip net.IP) (ok bool) {
+func (r *RDNS) isCached(ip netip.Addr) (ok bool) {
+	ipBytes := ip.AsSlice()
 	now := uint64(time.Now().Unix())
-	if expire := r.ipCache.Get(ip); len(expire) != 0 {
+	if expire := r.ipCache.Get(ipBytes); len(expire) != 0 {
 		if binary.BigEndian.Uint64(expire) > now {
 			return true
 		}
@@ -91,14 +92,14 @@ func (r *RDNS) isCached(ip net.IP) (ok bool) {
 	// The cache entry either expired or doesn't exist.
 	ttl := make([]byte, 8)
 	binary.BigEndian.PutUint64(ttl, now+defaultRDNSCacheTTL)
-	r.ipCache.Set(ip, ttl)
+	r.ipCache.Set(ipBytes, ttl)
 
 	return false
 }
 
 // Begin adds the ip to the resolving queue if it is not cached or already
 // resolved.
-func (r *RDNS) Begin(ip net.IP) {
+func (r *RDNS) Begin(ip netip.Addr) {
 	r.ensurePrivateCache()
 
 	if r.isCached(ip) || r.clients.exists(ip, ClientSourceRDNS) {
@@ -107,9 +108,9 @@ func (r *RDNS) Begin(ip net.IP) {
 
 	select {
 	case r.ipCh <- ip:
-		log.Tracef("rdns: %q added to queue", ip)
+		log.Debug("rdns: %q added to queue", ip)
 	default:
-		log.Tracef("rdns: queue is full")
+		log.Debug("rdns: queue is full")
 	}
 }
 
@@ -119,7 +120,7 @@ func (r *RDNS) workerLoop() {
 	defer log.OnPanic("rdns")
 
 	for ip := range r.ipCh {
-		host, err := r.exchanger.Exchange(ip)
+		host, err := r.exchanger.Exchange(ip.AsSlice())
 		if err != nil {
 			log.Debug("rdns: resolving %q: %s", ip, err)
 
@@ -128,8 +129,6 @@ func (r *RDNS) workerLoop() {
 			continue
 		}
 
-		// Don't handle any errors since AddHost doesn't return non-nil errors
-		// for now.
-		_, _ = r.clients.AddHost(ip, host, ClientSourceRDNS)
+		_ = r.clients.AddHost(ip, host, ClientSourceRDNS)
 	}
 }

internal/home/rdns_test.go

@@ -27,14 +27,14 @@ func TestRDNS_Begin(t *testing.T) {
 	w := &bytes.Buffer{}
 	aghtest.ReplaceLogWriter(t, w)
 
-	ip1234, ip1235 := net.IP{1, 2, 3, 4}, net.IP{1, 2, 3, 5}
+	ip1234, ip1235 := netip.MustParseAddr("1.2.3.4"), netip.MustParseAddr("1.2.3.5")
 
 	testCases := []struct {
 		cliIDIndex    map[string]*Client
-		customChan    chan net.IP
+		customChan    chan netip.Addr
 		name          string
 		wantLog       string
-		req           net.IP
+		ip            netip.Addr
 		wantCacheHit  int
 		wantCacheMiss int
 	}{{
@@ -42,7 +42,7 @@ func TestRDNS_Begin(t *testing.T) {
 		customChan:    nil,
 		name:          "cached",
 		wantLog:       "",
-		req:           ip1234,
+		ip:            ip1234,
 		wantCacheHit:  1,
 		wantCacheMiss: 0,
 	}, {
@@ -50,7 +50,7 @@ func TestRDNS_Begin(t *testing.T) {
 		customChan:    nil,
 		name:          "not_cached",
 		wantLog:       "rdns: queue is full",
-		req:           ip1235,
+		ip:            ip1235,
 		wantCacheHit:  0,
 		wantCacheMiss: 1,
 	}, {
@@ -58,15 +58,15 @@ func TestRDNS_Begin(t *testing.T) {
 		customChan:    nil,
 		name:          "already_in_clients",
 		wantLog:       "",
-		req:           ip1235,
+		ip:            ip1235,
 		wantCacheHit:  0,
 		wantCacheMiss: 1,
 	}, {
 		cliIDIndex:    map[string]*Client{},
-		customChan:    make(chan net.IP, 1),
+		customChan:    make(chan netip.Addr, 1),
 		name:          "add_to_queue",
 		wantLog:       `rdns: "1.2.3.5" added to queue`,
-		req:           ip1235,
+		ip:            ip1235,
 		wantCacheHit:  0,
 		wantCacheMiss: 1,
 	}}
@@ -102,7 +102,7 @@ func TestRDNS_Begin(t *testing.T) {
 		}
 
 		t.Run(tc.name, func(t *testing.T) {
-			rdns.Begin(tc.req)
+			rdns.Begin(tc.ip)
 			assert.Equal(t, tc.wantCacheHit, ipCache.Stats().Hit)
 			assert.Equal(t, tc.wantCacheMiss, ipCache.Stats().Miss)
 			assert.Contains(t, w.String(), tc.wantLog)
@@ -179,8 +179,8 @@ func TestRDNS_WorkerLoop(t *testing.T) {
 	w := &bytes.Buffer{}
 	aghtest.ReplaceLogWriter(t, w)
 
-	localIP := net.IP{192, 168, 1, 1}
-	revIPv4, err := netutil.IPToReversedAddr(localIP)
+	localIP := netip.MustParseAddr("192.168.1.1")
+	revIPv4, err := netutil.IPToReversedAddr(localIP.AsSlice())
 	require.NoError(t, err)
 
 	revIPv6, err := netutil.IPToReversedAddr(net.ParseIP("2a00:1450:400c:c06::93"))
@@ -201,24 +201,24 @@ func TestRDNS_WorkerLoop(t *testing.T) {
 
 	testCases := []struct {
 		ups     upstream.Upstream
+		cliIP   netip.Addr
 		wantLog string
 		name    string
-		cliIP   net.IP
 	}{{
 		ups:     locUpstream,
+		cliIP:   localIP,
 		wantLog: "",
 		name:    "all_good",
-		cliIP:   localIP,
 	}, {
 		ups:     errUpstream,
+		cliIP:   netip.MustParseAddr("192.168.1.2"),
 		wantLog: `rdns: resolving "192.168.1.2": test upstream error`,
 		name:    "resolve_error",
-		cliIP:   net.IP{192, 168, 1, 2},
 	}, {
 		ups:     locUpstream,
+		cliIP:   netip.MustParseAddr("2a00:1450:400c:c06::93"),
 		wantLog: "",
 		name:    "ipv6_good",
-		cliIP:   net.ParseIP("2a00:1450:400c:c06::93"),
 	}}
 
 	for _, tc := range testCases {
@@ -230,7 +230,7 @@ func TestRDNS_WorkerLoop(t *testing.T) {
 			ipToRC:  map[netip.Addr]*RuntimeClient{},
 			allTags: stringutil.NewSet(),
 		}
-		ch := make(chan net.IP)
+		ch := make(chan netip.Addr)
 		rdns := &RDNS{
 			exchanger: &rDNSExchanger{
 				ex: tc.ups,

internal/home/tls.go

@@ -8,42 +8,39 @@ import (
 	"crypto/rsa"
 	"crypto/tls"
 	"crypto/x509"
-	"encoding/base64"
-	"encoding/json"
 	"encoding/pem"
 	"fmt"
-	"net/http"
 	"os"
 	"strings"
 	"sync"
 	"time"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/aghalg"
-	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghtls"
-	"github.com/AdguardTeam/AdGuardHome/internal/dnsforward"
 	"github.com/AdguardTeam/golibs/errors"
 	"github.com/AdguardTeam/golibs/log"
-	"github.com/google/go-cmp/cmp"
 )
 
 // tlsManager contains the current configuration and state of AdGuard Home TLS
 // encryption.
 type tlsManager struct {
-	// status is the current status of the configuration.  It is never nil.
-	status *tlsConfigStatus
+	// mu protects all fields.
+	mu *sync.RWMutex
 
 	// certLastMod is the last modification time of the certificate file.
 	certLastMod time.Time
 
-	confLock sync.Mutex
-	conf     tlsConfigSettings
+	// status is the current status of the configuration.  It is never nil.
+	status *tlsConfigStatus
+
+	// conf is the current TLS configuration.
+	conf *tlsConfiguration
 }
 
 // newTLSManager initializes the TLS configuration.
-func newTLSManager(conf tlsConfigSettings) (m *tlsManager, err error) {
+func newTLSManager(conf *tlsConfiguration) (m *tlsManager, err error) {
 	m = &tlsManager{
 		status: &tlsConfigStatus{},
+		mu:     &sync.RWMutex{},
 		conf:   conf,
 	}
 
@@ -59,9 +56,19 @@ func newTLSManager(conf tlsConfigSettings) (m *tlsManager, err error) {
 	return m, nil
 }
 
+// confForEncoding returns a partial clone of the current TLS configuration.  It
+// is safe for concurrent use.
+func (m *tlsManager) confForEncoding() (conf *tlsConfiguration) {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	return m.conf.cloneForEncoding()
+}
+
 // load reloads the TLS configuration from files or data from the config file.
+// m.mu is expected to be locked for writing.
 func (m *tlsManager) load() (err error) {
-	err = loadTLSConf(&m.conf, m.status)
+	err = loadTLSConf(m.conf, m.status)
 	if err != nil {
 		return fmt.Errorf("loading config: %w", err)
 	}
@@ -70,14 +77,12 @@ func (m *tlsManager) load() (err error) {
 }
 
 // WriteDiskConfig - write config
-func (m *tlsManager) WriteDiskConfig(conf *tlsConfigSettings) {
-	m.confLock.Lock()
-	*conf = m.conf
-	m.confLock.Unlock()
+func (m *tlsManager) WriteDiskConfig(conf *tlsConfiguration) {
+	*conf = *m.confForEncoding()
 }
 
 // setCertFileTime sets t.certLastMod from the certificate.  If there are
-// errors, setCertFileTime logs them.
+// errors, setCertFileTime logs them.  mu is expected to be locked for writing.
 func (m *tlsManager) setCertFileTime() {
 	if len(m.conf.CertificatePath) == 0 {
 		return
@@ -97,27 +102,22 @@ func (m *tlsManager) setCertFileTime() {
 func (m *tlsManager) start() {
 	m.registerWebHandlers()
 
-	m.confLock.Lock()
-	tlsConf := m.conf
-	m.confLock.Unlock()
-
 	// The background context is used because the TLSConfigChanged wraps context
 	// with timeout on its own and shuts down the server, which handles current
 	// request.
-	Context.web.TLSConfigChanged(context.Background(), tlsConf)
+	Context.web.TLSConfigChanged(context.Background(), m.confForEncoding())
 }
 
-// reload updates the configuration and restarts t.
+// reload updates the configuration and restarts m.
 func (m *tlsManager) reload() {
-	m.confLock.Lock()
-	tlsConf := m.conf
-	m.confLock.Unlock()
+	m.mu.Lock()
+	defer m.mu.Unlock()
 
-	if !tlsConf.Enabled || len(tlsConf.CertificatePath) == 0 {
+	if !m.conf.Enabled || len(m.conf.CertificatePath) == 0 {
 		return
 	}
 
-	fi, err := os.Stat(tlsConf.CertificatePath)
+	fi, err := os.Stat(m.conf.CertificatePath)
 	if err != nil {
 		log.Error("tls: %s", err)
 
@@ -132,9 +132,7 @@ func (m *tlsManager) reload() {
 
 	log.Debug("tls: certificate file is modified")
 
-	m.confLock.Lock()
 	err = m.load()
-	m.confLock.Unlock()
 	if err != nil {
 		log.Error("tls: reloading: %s", err)
 
@@ -145,19 +143,15 @@ func (m *tlsManager) reload() {
 
 	_ = reconfigureDNSServer()
 
-	m.confLock.Lock()
-	tlsConf = m.conf
-	m.confLock.Unlock()
-
 	// The background context is used because the TLSConfigChanged wraps context
 	// with timeout on its own and shuts down the server, which handles current
 	// request.
-	Context.web.TLSConfigChanged(context.Background(), tlsConf)
+	Context.web.TLSConfigChanged(context.Background(), m.conf)
 }
 
 // loadTLSConf loads and validates the TLS configuration.  The returned error is
 // also set in status.WarningValidation.
-func loadTLSConf(tlsConf *tlsConfigSettings, status *tlsConfigStatus) (err error) {
+func loadTLSConf(tlsConf *tlsConfiguration, status *tlsConfigStatus) (err error) {
 	defer func() {
 		if err != nil {
 			status.WarningValidation = err.Error()
@@ -172,13 +166,10 @@ func loadTLSConf(tlsConf *tlsConfigSettings, status *tlsConfigStatus) (err error
 	tlsConf.PrivateKeyData = []byte(tlsConf.PrivateKey)
 
 	if tlsConf.CertificatePath != "" {
-		if tlsConf.CertificateChain != "" {
-			return errors.Error("certificate data and file can't be set together")
-		}
-
-		tlsConf.CertificateChainData, err = os.ReadFile(tlsConf.CertificatePath)
+		err = loadCert(tlsConf)
 		if err != nil {
-			return fmt.Errorf("reading cert file: %w", err)
+			// Don't wrap the error, since it's informative enough as is.
+			return err
 		}
 
 		// Set status.ValidCert to true to signal the frontend that the
@@ -187,13 +178,10 @@ func loadTLSConf(tlsConf *tlsConfigSettings, status *tlsConfigStatus) (err error
 	}
 
 	if tlsConf.PrivateKeyPath != "" {
-		if tlsConf.PrivateKey != "" {
-			return errors.Error("private key data and file can't be set together")
-		}
-
-		tlsConf.PrivateKeyData, err = os.ReadFile(tlsConf.PrivateKeyPath)
+		err = loadPKey(tlsConf)
 		if err != nil {
-			return fmt.Errorf("reading key file: %w", err)
+			// Don't wrap the error, since it's informative enough as is.
+			return err
 		}
 
 		status.ValidKey = true
@@ -212,278 +200,29 @@ func loadTLSConf(tlsConf *tlsConfigSettings, status *tlsConfigStatus) (err error
 	return nil
 }
 
-// tlsConfigStatus contains the status of a certificate chain and key pair.
-type tlsConfigStatus struct {
-	// Subject is the subject of the first certificate in the chain.
-	Subject string `json:"subject,omitempty"`
-
-	// Issuer is the issuer of the first certificate in the chain.
-	Issuer string `json:"issuer,omitempty"`
-
-	// KeyType is the type of the private key.
-	KeyType string `json:"key_type,omitempty"`
-
-	// NotBefore is the NotBefore field of the first certificate in the chain.
-	NotBefore time.Time `json:"not_before,omitempty"`
-
-	// NotAfter is the NotAfter field of the first certificate in the chain.
-	NotAfter time.Time `json:"not_after,omitempty"`
-
-	// WarningValidation is a validation warning message with the issue
-	// description.
-	WarningValidation string `json:"warning_validation,omitempty"`
-
-	// DNSNames is the value of SubjectAltNames field of the first certificate
-	// in the chain.
-	DNSNames []string `json:"dns_names"`
-
-	// ValidCert is true if the specified certificate chain is a valid chain of
-	// X509 certificates.
-	ValidCert bool `json:"valid_cert"`
-
-	// ValidChain is true if the specified certificate chain is verified and
-	// issued by a known CA.
-	ValidChain bool `json:"valid_chain"`
-
-	// ValidKey is true if the key is a valid private key.
-	ValidKey bool `json:"valid_key"`
-
-	// ValidPair is true if both certificate and private key are correct for
-	// each other.
-	ValidPair bool `json:"valid_pair"`
-}
-
-// tlsConfig is the TLS configuration and status response.
-type tlsConfig struct {
-	*tlsConfigStatus     `json:",inline"`
-	tlsConfigSettingsExt `json:",inline"`
-}
-
-// tlsConfigSettingsExt is used to (un)marshal the PrivateKeySaved field to
-// ensure that clients don't send and receive previously saved private keys.
-type tlsConfigSettingsExt struct {
-	tlsConfigSettings `json:",inline"`
-
-	// PrivateKeySaved is true if the private key is saved as a string and omit
-	// key from answer.
-	PrivateKeySaved bool `yaml:"-" json:"private_key_saved,inline"`
-}
-
-func (m *tlsManager) handleTLSStatus(w http.ResponseWriter, r *http.Request) {
-	m.confLock.Lock()
-	data := tlsConfig{
-		tlsConfigSettingsExt: tlsConfigSettingsExt{
-			tlsConfigSettings: m.conf,
-		},
-		tlsConfigStatus: m.status,
+// loadCert loads the certificate from file, if necessary.
+func loadCert(tlsConf *tlsConfiguration) (err error) {
+	if tlsConf.CertificateChain != "" {
+		return errors.Error("certificate data and file can't be set together")
 	}
-	m.confLock.Unlock()
 
-	marshalTLS(w, r, data)
-}
-
-func (m *tlsManager) handleTLSValidate(w http.ResponseWriter, r *http.Request) {
-	setts, err := unmarshalTLS(r)
+	tlsConf.CertificateChainData, err = os.ReadFile(tlsConf.CertificatePath)
 	if err != nil {
-		aghhttp.Error(r, w, http.StatusBadRequest, "Failed to unmarshal TLS config: %s", err)
-
-		return
+		return fmt.Errorf("reading cert file: %w", err)
 	}
 
-	if setts.PrivateKeySaved {
-		setts.PrivateKey = m.conf.PrivateKey
-	}
-
-	if setts.Enabled {
-		err = validatePorts(
-			tcpPort(config.BindPort),
-			tcpPort(config.BetaBindPort),
-			tcpPort(setts.PortHTTPS),
-			tcpPort(setts.PortDNSOverTLS),
-			tcpPort(setts.PortDNSCrypt),
-			udpPort(config.DNS.Port),
-			udpPort(setts.PortDNSOverQUIC),
-		)
-		if err != nil {
-			aghhttp.Error(r, w, http.StatusBadRequest, "%s", err)
-
-			return
-		}
-	}
-
-	if !webCheckPortAvailable(setts.PortHTTPS) {
-		aghhttp.Error(
-			r,
-			w,
-			http.StatusBadRequest,
-			"port %d is not available, cannot enable HTTPS on it",
-			setts.PortHTTPS,
-		)
-
-		return
-	}
-
-	// Skip the error check, since we are only interested in the value of
-	// status.WarningValidation.
-	status := &tlsConfigStatus{}
-	_ = loadTLSConf(&setts.tlsConfigSettings, status)
-	resp := tlsConfig{
-		tlsConfigSettingsExt: setts,
-		tlsConfigStatus:      status,
-	}
-
-	marshalTLS(w, r, resp)
+	return nil
 }
 
-func (m *tlsManager) setConfig(newConf tlsConfigSettings, status *tlsConfigStatus) (restartHTTPS bool) {
-	m.confLock.Lock()
-	defer m.confLock.Unlock()
-
-	// Reset the DNSCrypt data before comparing, since we currently do not
-	// accept these from the frontend.
-	//
-	// TODO(a.garipov): Define a custom comparer for dnsforward.TLSConfig.
-	newConf.DNSCryptConfigFile = m.conf.DNSCryptConfigFile
-	newConf.PortDNSCrypt = m.conf.PortDNSCrypt
-	if !cmp.Equal(m.conf, newConf, cmp.AllowUnexported(dnsforward.TLSConfig{})) {
-		log.Info("tls config has changed, restarting https server")
-		restartHTTPS = true
-	} else {
-		log.Info("tls: config has not changed")
+// loadPKey loads the private key from file, if necessary.
+func loadPKey(tlsConf *tlsConfiguration) (err error) {
+	if tlsConf.PrivateKey != "" {
+		return errors.Error("private key data and file cannot be set together")
 	}
 
-	// Note: don't do just `t.conf = data` because we must preserve all other members of t.conf
-	m.conf.Enabled = newConf.Enabled
-	m.conf.ServerName = newConf.ServerName
-	m.conf.ForceHTTPS = newConf.ForceHTTPS
-	m.conf.PortHTTPS = newConf.PortHTTPS
-	m.conf.PortDNSOverTLS = newConf.PortDNSOverTLS
-	m.conf.PortDNSOverQUIC = newConf.PortDNSOverQUIC
-	m.conf.CertificateChain = newConf.CertificateChain
-	m.conf.CertificatePath = newConf.CertificatePath
-	m.conf.CertificateChainData = newConf.CertificateChainData
-	m.conf.PrivateKey = newConf.PrivateKey
-	m.conf.PrivateKeyPath = newConf.PrivateKeyPath
-	m.conf.PrivateKeyData = newConf.PrivateKeyData
-	m.status = status
-
-	return restartHTTPS
-}
-
-func (m *tlsManager) handleTLSConfigure(w http.ResponseWriter, r *http.Request) {
-	req, err := unmarshalTLS(r)
+	tlsConf.PrivateKeyData, err = os.ReadFile(tlsConf.PrivateKeyPath)
 	if err != nil {
-		aghhttp.Error(r, w, http.StatusBadRequest, "Failed to unmarshal TLS config: %s", err)
-
-		return
-	}
-
-	if req.PrivateKeySaved {
-		req.PrivateKey = m.conf.PrivateKey
-	}
-
-	if req.Enabled {
-		err = validatePorts(
-			tcpPort(config.BindPort),
-			tcpPort(config.BetaBindPort),
-			tcpPort(req.PortHTTPS),
-			tcpPort(req.PortDNSOverTLS),
-			tcpPort(req.PortDNSCrypt),
-			udpPort(config.DNS.Port),
-			udpPort(req.PortDNSOverQUIC),
-		)
-		if err != nil {
-			aghhttp.Error(r, w, http.StatusBadRequest, "%s", err)
-
-			return
-		}
-	}
-
-	// TODO(e.burkov):  Investigate and perhaps check other ports.
-	if !webCheckPortAvailable(req.PortHTTPS) {
-		aghhttp.Error(
-			r,
-			w,
-			http.StatusBadRequest,
-			"port %d is not available, cannot enable https on it",
-			req.PortHTTPS,
-		)
-
-		return
-	}
-
-	status := &tlsConfigStatus{}
-	err = loadTLSConf(&req.tlsConfigSettings, status)
-	if err != nil {
-		resp := tlsConfig{
-			tlsConfigSettingsExt: req,
-			tlsConfigStatus:      status,
-		}
-
-		marshalTLS(w, r, resp)
-
-		return
-	}
-
-	restartHTTPS := m.setConfig(req.tlsConfigSettings, status)
-	m.setCertFileTime()
-	onConfigModified()
-
-	err = reconfigureDNSServer()
-	if err != nil {
-		aghhttp.Error(r, w, http.StatusInternalServerError, "%s", err)
-
-		return
-	}
-
-	resp := tlsConfig{
-		tlsConfigSettingsExt: req,
-		tlsConfigStatus:      m.status,
-	}
-
-	marshalTLS(w, r, resp)
-	if f, ok := w.(http.Flusher); ok {
-		f.Flush()
-	}
-
-	// The background context is used because the TLSConfigChanged wraps context
-	// with timeout on its own and shuts down the server, which handles current
-	// request. It is also should be done in a separate goroutine due to the
-	// same reason.
-	if restartHTTPS {
-		go func() {
-			Context.web.TLSConfigChanged(context.Background(), req.tlsConfigSettings)
-		}()
-	}
-}
-
-// validatePorts validates the uniqueness of TCP and UDP ports for AdGuard Home
-// DNS protocols.
-func validatePorts(
-	bindPort, betaBindPort, dohPort, dotPort, dnscryptTCPPort tcpPort,
-	dnsPort, doqPort udpPort,
-) (err error) {
-	tcpPorts := aghalg.UniqChecker[tcpPort]{}
-	addPorts(
-		tcpPorts,
-		tcpPort(bindPort),
-		tcpPort(betaBindPort),
-		tcpPort(dohPort),
-		tcpPort(dotPort),
-		tcpPort(dnscryptTCPPort),
-	)
-
-	err = tcpPorts.Validate()
-	if err != nil {
-		return fmt.Errorf("validating tcp ports: %w", err)
-	}
-
-	udpPorts := aghalg.UniqChecker[udpPort]{}
-	addPorts(udpPorts, udpPort(dnsPort), udpPort(doqPort))
-
-	err = udpPorts.Validate()
-	if err != nil {
-		return fmt.Errorf("validating udp ports: %w", err)
+		return fmt.Errorf("reading key file: %w", err)
 	}
 
 	return nil
@@ -513,6 +252,11 @@ func validateCertChain(certs []*x509.Certificate, srvName string) (err error) {
 	return nil
 }
 
+// errNoIPInCert is the error that is returned from [parseCertChain] if the leaf
+// certificate doesn't contain IPs.
+const errNoIPInCert errors.Error = `certificates has no IP addresses; ` +
+	`DNS-over-TLS won't be advertised via DDR`
+
 // parseCertChain parses the certificate chain from raw data, and returns it.
 // If ok is true, the returned error, if any, is not critical.
 func parseCertChain(chain []byte) (parsedCerts []*x509.Certificate, ok bool, err error) {
@@ -535,8 +279,7 @@ func parseCertChain(chain []byte) (parsedCerts []*x509.Certificate, ok bool, err
 	log.Info("tls: number of certs: %d", len(parsedCerts))
 
 	if !aghtls.CertificateHasIP(parsedCerts[0]) {
-		err = errors.Error(`certificate has no IP addresses` +
-			`, this may cause issues with DNS-over-TLS clients`)
+		err = errNoIPInCert
 	}
 
 	return parsedCerts, true, err
@@ -696,61 +439,3 @@ func parsePrivateKey(der []byte) (key crypto.PrivateKey, typ string, err error)
 
 	return nil, "", errors.Error("tls: failed to parse private key")
 }
-
-// unmarshalTLS handles base64-encoded certificates transparently
-func unmarshalTLS(r *http.Request) (tlsConfigSettingsExt, error) {
-	data := tlsConfigSettingsExt{}
-	err := json.NewDecoder(r.Body).Decode(&data)
-	if err != nil {
-		return data, fmt.Errorf("failed to parse new TLS config json: %w", err)
-	}
-
-	if data.CertificateChain != "" {
-		var cert []byte
-		cert, err = base64.StdEncoding.DecodeString(data.CertificateChain)
-		if err != nil {
-			return data, fmt.Errorf("failed to base64-decode certificate chain: %w", err)
-		}
-
-		data.CertificateChain = string(cert)
-		if data.CertificatePath != "" {
-			return data, fmt.Errorf("certificate data and file can't be set together")
-		}
-	}
-
-	if data.PrivateKey != "" {
-		var key []byte
-		key, err = base64.StdEncoding.DecodeString(data.PrivateKey)
-		if err != nil {
-			return data, fmt.Errorf("failed to base64-decode private key: %w", err)
-		}
-
-		data.PrivateKey = string(key)
-		if data.PrivateKeyPath != "" {
-			return data, fmt.Errorf("private key data and file can't be set together")
-		}
-	}
-
-	return data, nil
-}
-
-func marshalTLS(w http.ResponseWriter, r *http.Request, data tlsConfig) {
-	if data.CertificateChain != "" {
-		encoded := base64.StdEncoding.EncodeToString([]byte(data.CertificateChain))
-		data.CertificateChain = encoded
-	}
-
-	if data.PrivateKey != "" {
-		data.PrivateKeySaved = true
-		data.PrivateKey = ""
-	}
-
-	_ = aghhttp.WriteJSONResponse(w, r, data)
-}
-
-// registerWebHandlers registers HTTP handlers for TLS configuration.
-func (m *tlsManager) registerWebHandlers() {
-	httpRegister(http.MethodGet, "/control/tls/status", m.handleTLSStatus)
-	httpRegister(http.MethodPost, "/control/tls/configure", m.handleTLSConfigure)
-	httpRegister(http.MethodPost, "/control/tls/validate", m.handleTLSValidate)
-}

internal/home/tlshttp.go

@@ -0,0 +1,362 @@
+package home
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghalg"
+	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
+	"github.com/AdguardTeam/AdGuardHome/internal/dnsforward"
+	"github.com/AdguardTeam/golibs/log"
+	"github.com/google/go-cmp/cmp"
+)
+
+// Encryption Settings HTTP API
+
+// tlsConfigStatus contains the status of a certificate chain and key pair.
+type tlsConfigStatus struct {
+	// Subject is the subject of the first certificate in the chain.
+	Subject string `json:"subject,omitempty"`
+
+	// Issuer is the issuer of the first certificate in the chain.
+	Issuer string `json:"issuer,omitempty"`
+
+	// KeyType is the type of the private key.
+	KeyType string `json:"key_type,omitempty"`
+
+	// NotBefore is the NotBefore field of the first certificate in the chain.
+	NotBefore time.Time `json:"not_before,omitempty"`
+
+	// NotAfter is the NotAfter field of the first certificate in the chain.
+	NotAfter time.Time `json:"not_after,omitempty"`
+
+	// WarningValidation is a validation warning message with the issue
+	// description.
+	WarningValidation string `json:"warning_validation,omitempty"`
+
+	// DNSNames is the value of SubjectAltNames field of the first certificate
+	// in the chain.
+	DNSNames []string `json:"dns_names"`
+
+	// ValidCert is true if the specified certificate chain is a valid chain of
+	// X509 certificates.
+	ValidCert bool `json:"valid_cert"`
+
+	// ValidChain is true if the specified certificate chain is verified and
+	// issued by a known CA.
+	ValidChain bool `json:"valid_chain"`
+
+	// ValidKey is true if the key is a valid private key.
+	ValidKey bool `json:"valid_key"`
+
+	// ValidPair is true if both certificate and private key are correct for
+	// each other.
+	ValidPair bool `json:"valid_pair"`
+}
+
+// tlsConfigResp is the TLS configuration and status response.
+type tlsConfigResp struct {
+	*tlsConfigStatus
+	*tlsConfiguration
+
+	// PrivateKeySaved is true if the private key is saved as a string and omit
+	// key from answer.
+	PrivateKeySaved bool `yaml:"-" json:"private_key_saved"`
+}
+
+// tlsConfigReq is the TLS configuration request.
+type tlsConfigReq struct {
+	tlsConfiguration
+
+	// PrivateKeySaved is true if the private key is saved as a string and omit
+	// key from answer.
+	PrivateKeySaved bool `yaml:"-" json:"private_key_saved"`
+}
+
+// handleTLSStatus is the handler for the GET /control/tls/status HTTP API.
+func (m *tlsManager) handleTLSStatus(w http.ResponseWriter, r *http.Request) {
+	var resp *tlsConfigResp
+	func() {
+		m.mu.RLock()
+		defer m.mu.RUnlock()
+
+		resp = &tlsConfigResp{
+			tlsConfigStatus:  m.status,
+			tlsConfiguration: m.conf.cloneForEncoding(),
+		}
+	}()
+
+	marshalTLS(w, r, resp)
+}
+
+// handleTLSValidate is the handler for the POST /control/tls/validate HTTP API.
+func (m *tlsManager) handleTLSValidate(w http.ResponseWriter, r *http.Request) {
+	req, err := unmarshalTLS(r)
+	if err != nil {
+		aghhttp.Error(r, w, http.StatusBadRequest, "Failed to unmarshal TLS config: %s", err)
+
+		return
+	}
+
+	if req.PrivateKeySaved {
+		req.PrivateKey = m.confForEncoding().PrivateKey
+	}
+
+	if req.Enabled {
+		err = validatePorts(
+			tcpPort(config.BindPort),
+			tcpPort(config.BetaBindPort),
+			tcpPort(req.PortHTTPS),
+			tcpPort(req.PortDNSOverTLS),
+			tcpPort(req.PortDNSCrypt),
+			udpPort(config.DNS.Port),
+			udpPort(req.PortDNSOverQUIC),
+		)
+		if err != nil {
+			aghhttp.Error(r, w, http.StatusBadRequest, "%s", err)
+
+			return
+		}
+	}
+
+	if !webCheckPortAvailable(req.PortHTTPS) {
+		aghhttp.Error(
+			r,
+			w,
+			http.StatusBadRequest,
+			"port %d is not available, cannot enable HTTPS on it",
+			req.PortHTTPS,
+		)
+
+		return
+	}
+
+	resp := &tlsConfigResp{
+		tlsConfigStatus:  &tlsConfigStatus{},
+		tlsConfiguration: &req.tlsConfiguration,
+	}
+
+	// Skip the error check, since we are only interested in the value of
+	// resl.tlsConfigStatus.WarningValidation.
+	_ = loadTLSConf(resp.tlsConfiguration, resp.tlsConfigStatus)
+
+	marshalTLS(w, r, resp)
+}
+
+// validatePorts validates the uniqueness of TCP and UDP ports for AdGuard Home
+// DNS protocols.
+func validatePorts(
+	bindPort, betaBindPort, dohPort, dotPort, dnscryptTCPPort tcpPort,
+	dnsPort, doqPort udpPort,
+) (err error) {
+	tcpPorts := aghalg.UniqChecker[tcpPort]{}
+	addPorts(
+		tcpPorts,
+		tcpPort(bindPort),
+		tcpPort(betaBindPort),
+		tcpPort(dohPort),
+		tcpPort(dotPort),
+		tcpPort(dnscryptTCPPort),
+	)
+
+	err = tcpPorts.Validate()
+	if err != nil {
+		return fmt.Errorf("validating tcp ports: %w", err)
+	}
+
+	udpPorts := aghalg.UniqChecker[udpPort]{}
+	addPorts(udpPorts, udpPort(dnsPort), udpPort(doqPort))
+
+	err = udpPorts.Validate()
+	if err != nil {
+		return fmt.Errorf("validating udp ports: %w", err)
+	}
+
+	return nil
+}
+
+// handleTLSConfigure is the handler for the POST /control/tls/configure HTTP
+// API.
+func (m *tlsManager) handleTLSConfigure(w http.ResponseWriter, r *http.Request) {
+	req, err := unmarshalTLS(r)
+	if err != nil {
+		aghhttp.Error(r, w, http.StatusBadRequest, "Failed to unmarshal TLS config: %s", err)
+
+		return
+	}
+
+	if req.PrivateKeySaved {
+		req.PrivateKey = m.confForEncoding().PrivateKey
+	}
+
+	if req.Enabled {
+		err = validatePorts(
+			tcpPort(config.BindPort),
+			tcpPort(config.BetaBindPort),
+			tcpPort(req.PortHTTPS),
+			tcpPort(req.PortDNSOverTLS),
+			tcpPort(req.PortDNSCrypt),
+			udpPort(config.DNS.Port),
+			udpPort(req.PortDNSOverQUIC),
+		)
+		if err != nil {
+			aghhttp.Error(r, w, http.StatusBadRequest, "%s", err)
+
+			return
+		}
+	}
+
+	// TODO(e.burkov):  Investigate and perhaps check other ports.
+	if !webCheckPortAvailable(req.PortHTTPS) {
+		aghhttp.Error(
+			r,
+			w,
+			http.StatusBadRequest,
+			"port %d is not available, cannot enable https on it",
+			req.PortHTTPS,
+		)
+
+		return
+	}
+
+	resp := &tlsConfigResp{
+		tlsConfigStatus:  &tlsConfigStatus{},
+		tlsConfiguration: &req.tlsConfiguration,
+	}
+	err = loadTLSConf(resp.tlsConfiguration, resp.tlsConfigStatus)
+	if err != nil {
+		marshalTLS(w, r, resp)
+
+		return
+	}
+
+	restartRequired := m.setConf(resp)
+	onConfigModified()
+
+	err = reconfigureDNSServer()
+	if err != nil {
+		aghhttp.Error(r, w, http.StatusInternalServerError, "%s", err)
+
+		return
+	}
+
+	resp.tlsConfiguration = m.confForEncoding()
+	marshalTLS(w, r, resp)
+	if f, ok := w.(http.Flusher); ok {
+		f.Flush()
+	}
+
+	// The background context is used because the TLSConfigChanged wraps context
+	// with timeout on its own and shuts down the server, which handles current
+	// request. It is also should be done in a separate goroutine due to the
+	// same reason.
+	if restartRequired {
+		go func() {
+			Context.web.TLSConfigChanged(context.Background(), resp.tlsConfiguration)
+		}()
+	}
+}
+
+// setConf sets the necessary values from the new configuration.
+func (m *tlsManager) setConf(newConf *tlsConfigResp) (restartRequired bool) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	// Reset the DNSCrypt data before comparing, since we currently do not
+	// accept these from the frontend.
+	//
+	// TODO(a.garipov): Define a custom comparer for dnsforward.TLSConfig.
+	newConf.DNSCryptConfigFile = m.conf.DNSCryptConfigFile
+	newConf.PortDNSCrypt = m.conf.PortDNSCrypt
+	if !cmp.Equal(m.conf, newConf, cmp.AllowUnexported(dnsforward.TLSConfig{})) {
+		log.Info("tls: config has changed, restarting https server")
+		restartRequired = true
+	} else {
+		log.Info("tls: config has not changed")
+	}
+
+	// Do not just write "m.conf = *newConf.tlsConfiguration", because all other
+	// members of m.conf must be preserved.
+	m.conf.Enabled = newConf.Enabled
+	m.conf.ServerName = newConf.ServerName
+	m.conf.ForceHTTPS = newConf.ForceHTTPS
+	m.conf.PortHTTPS = newConf.PortHTTPS
+	m.conf.PortDNSOverTLS = newConf.PortDNSOverTLS
+	m.conf.PortDNSOverQUIC = newConf.PortDNSOverQUIC
+
+	m.conf.CertificateChain = newConf.CertificateChain
+	m.conf.CertificatePath = newConf.CertificatePath
+	m.conf.CertificateChainData = newConf.CertificateChainData
+	m.conf.PrivateKey = newConf.PrivateKey
+	m.conf.PrivateKeyPath = newConf.PrivateKeyPath
+	m.conf.PrivateKeyData = newConf.PrivateKeyData
+
+	m.setCertFileTime()
+
+	m.status = newConf.tlsConfigStatus
+
+	return restartRequired
+}
+
+// marshalTLS handles Base64-encoded certificates transparently.
+func marshalTLS(w http.ResponseWriter, r *http.Request, conf *tlsConfigResp) {
+	if conf.CertificateChain != "" {
+		encoded := base64.StdEncoding.EncodeToString([]byte(conf.CertificateChain))
+		conf.CertificateChain = encoded
+	}
+
+	if conf.PrivateKey != "" {
+		conf.PrivateKeySaved = true
+		conf.PrivateKey = ""
+	}
+
+	_ = aghhttp.WriteJSONResponse(w, r, conf)
+}
+
+// unmarshalTLS handles Base64-encoded certificates transparently.
+func unmarshalTLS(r *http.Request) (req *tlsConfigReq, err error) {
+	req = &tlsConfigReq{}
+	err = json.NewDecoder(r.Body).Decode(req)
+	if err != nil {
+		return nil, fmt.Errorf("parsing tls config: %w", err)
+	}
+
+	if req.CertificateChain != "" {
+		var cert []byte
+		cert, err = base64.StdEncoding.DecodeString(req.CertificateChain)
+		if err != nil {
+			return nil, fmt.Errorf("failed to base64-decode certificate chain: %w", err)
+		}
+
+		req.CertificateChain = string(cert)
+		if req.CertificatePath != "" {
+			return nil, fmt.Errorf("certificate data and file can't be set together")
+		}
+	}
+
+	if req.PrivateKey != "" {
+		var key []byte
+		key, err = base64.StdEncoding.DecodeString(req.PrivateKey)
+		if err != nil {
+			return nil, fmt.Errorf("failed to base64-decode private key: %w", err)
+		}
+
+		req.PrivateKey = string(key)
+		if req.PrivateKeyPath != "" {
+			return nil, fmt.Errorf("private key data and file can't be set together")
+		}
+	}
+
+	return req, nil
+}
+
+// registerWebHandlers registers HTTP handlers for TLS configuration.
+func (m *tlsManager) registerWebHandlers() {
+	httpRegister(http.MethodGet, "/control/tls/status", m.handleTLSStatus)
+	httpRegister(http.MethodPost, "/control/tls/configure", m.handleTLSConfigure)
+	httpRegister(http.MethodPost, "/control/tls/validate", m.handleTLSValidate)
+}

internal/home/web.go

@@ -143,7 +143,7 @@ func webCheckPortAvailable(port int) (ok bool) {
 
 // TLSConfigChanged updates the TLS configuration and restarts the HTTPS server
 // if necessary.
-func (web *Web) TLSConfigChanged(ctx context.Context, tlsConf tlsConfigSettings) {
+func (web *Web) TLSConfigChanged(ctx context.Context, tlsConf *tlsConfiguration) {
 	log.Debug("web: applying new tls configuration")
 	web.conf.PortHTTPS = tlsConf.PortHTTPS
 	web.forceHTTPS = (tlsConf.ForceHTTPS && tlsConf.Enabled && tlsConf.PortHTTPS != 0)

internal/home/whois.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"net"
+	"net/netip"
 	"strings"
 	"time"
 
@@ -26,7 +27,7 @@ const (
 // WHOIS - module context
 type WHOIS struct {
 	clients *clientsContainer
-	ipChan  chan net.IP
+	ipChan  chan netip.Addr
 
 	// dialContext specifies the dial function for creating unencrypted TCP
 	// connections.
@@ -51,7 +52,7 @@ func initWHOIS(clients *clientsContainer) *WHOIS {
 			MaxCount:  10000,
 		}),
 		dialContext: customDialContext,
-		ipChan:      make(chan net.IP, 255),
+		ipChan:      make(chan netip.Addr, 255),
 	}
 
 	go w.workerLoop()
@@ -192,7 +193,7 @@ func (w *WHOIS) queryAll(ctx context.Context, target string) (string, error) {
 }
 
 // Request WHOIS information
-func (w *WHOIS) process(ctx context.Context, ip net.IP) (wi *RuntimeClientWHOISInfo) {
+func (w *WHOIS) process(ctx context.Context, ip netip.Addr) (wi *RuntimeClientWHOISInfo) {
 	resp, err := w.queryAll(ctx, ip.String())
 	if err != nil {
 		log.Debug("whois: error: %s  IP:%s", err, ip)
@@ -220,24 +221,25 @@ func (w *WHOIS) process(ctx context.Context, ip net.IP) (wi *RuntimeClientWHOISI
 }
 
 // Begin - begin requesting WHOIS info
-func (w *WHOIS) Begin(ip net.IP) {
+func (w *WHOIS) Begin(ip netip.Addr) {
+	ipBytes := ip.AsSlice()
 	now := uint64(time.Now().Unix())
-	expire := w.ipAddrs.Get([]byte(ip))
+	expire := w.ipAddrs.Get(ipBytes)
 	if len(expire) != 0 {
 		exp := binary.BigEndian.Uint64(expire)
 		if exp > now {
 			return
 		}
-		// TTL expired
 	}
+
 	expire = make([]byte, 8)
 	binary.BigEndian.PutUint64(expire, now+whoisTTL)
-	_ = w.ipAddrs.Set([]byte(ip), expire)
+	_ = w.ipAddrs.Set(ipBytes, expire)
 
 	log.Debug("whois: adding %s", ip)
+
 	select {
 	case w.ipChan <- ip:
-		//
 	default:
 		log.Debug("whois: queue is full")
 	}

internal/next/agh/agh.go

@@ -0,0 +1,63 @@
+// Package agh contains common entities and interfaces of AdGuard Home.
+package agh
+
+import "context"
+
+// Service is the interface for API servers.
+//
+// TODO(a.garipov): Consider adding a context to Start.
+//
+// TODO(a.garipov): Consider adding a Wait method or making an extension
+// interface for that.
+type Service interface {
+	// Start starts the service.  It does not block.
+	Start() (err error)
+
+	// Shutdown gracefully stops the service.  ctx is used to determine
+	// a timeout before trying to stop the service less gracefully.
+	Shutdown(ctx context.Context) (err error)
+}
+
+// type check
+var _ Service = EmptyService{}
+
+// EmptyService is a [Service] that does nothing.
+//
+// TODO(a.garipov): Remove if unnecessary.
+type EmptyService struct{}
+
+// Start implements the [Service] interface for EmptyService.
+func (EmptyService) Start() (err error) { return nil }
+
+// Shutdown implements the [Service] interface for EmptyService.
+func (EmptyService) Shutdown(_ context.Context) (err error) { return nil }
+
+// ServiceWithConfig is an extension of the [Service] interface for services
+// that can return their configuration.
+//
+// TODO(a.garipov): Consider removing this generic interface if we figure out
+// how to make it testable in a better way.
+type ServiceWithConfig[ConfigType any] interface {
+	Service
+
+	Config() (c ConfigType)
+}
+
+// type check
+var _ ServiceWithConfig[struct{}] = (*EmptyServiceWithConfig[struct{}])(nil)
+
+// EmptyServiceWithConfig is a ServiceWithConfig that does nothing.  Its Config
+// method returns Conf.
+//
+// TODO(a.garipov): Remove if unnecessary.
+type EmptyServiceWithConfig[ConfigType any] struct {
+	EmptyService
+
+	Conf ConfigType
+}
+
+// Config implements the [ServiceWithConfig] interface for
+// *EmptyServiceWithConfig.
+func (s *EmptyServiceWithConfig[ConfigType]) Config() (conf ConfigType) {
+	return s.Conf
+}

internal/next/cmd/cmd.go

@@ -0,0 +1,77 @@
+// Package cmd is the AdGuard Home entry point.  It contains the on-disk
+// configuration file utilities, signal processing logic, and so on.
+//
+// TODO(a.garipov): Move to the upper-level internal/.
+package cmd
+
+import (
+	"context"
+	"io/fs"
+	"math/rand"
+	"os"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/configmgr"
+	"github.com/AdguardTeam/AdGuardHome/internal/version"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+// Main is the entry point of application.
+func Main(clientBuildFS fs.FS) {
+	// Initial Configuration
+
+	start := time.Now()
+	rand.Seed(start.UnixNano())
+
+	// TODO(a.garipov): Set up logging.
+
+	log.Info("starting adguard home, version %s, pid %d", version.Version(), os.Getpid())
+
+	// Web Service
+
+	// TODO(a.garipov): Use in the Web service.
+	_ = clientBuildFS
+
+	// TODO(a.garipov): Set up configuration file name.
+	const confFile = "AdGuardHome.1.yaml"
+
+	confMgr, err := configmgr.New(confFile, start)
+	fatalOnError(err)
+
+	web := confMgr.Web()
+	err = web.Start()
+	fatalOnError(err)
+
+	dns := confMgr.DNS()
+	err = dns.Start()
+	fatalOnError(err)
+
+	sigHdlr := newSignalHandler(
+		confFile,
+		start,
+		web,
+		dns,
+	)
+
+	go sigHdlr.handle()
+
+	select {}
+}
+
+// defaultTimeout is the timeout used for some operations where another timeout
+// hasn't been defined yet.
+const defaultTimeout = 15 * time.Second
+
+// ctxWithDefaultTimeout is a helper function that returns a context with
+// timeout set to defaultTimeout.
+func ctxWithDefaultTimeout() (ctx context.Context, cancel context.CancelFunc) {
+	return context.WithTimeout(context.Background(), defaultTimeout)
+}
+
+// fatalOnError is a helper that exits the program with an error code if err is
+// not nil.  It must only be used within Main.
+func fatalOnError(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
+}

internal/next/cmd/signal.go

@@ -0,0 +1,118 @@
+package cmd
+
+import (
+	"os"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghos"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/configmgr"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+// signalHandler processes incoming signals and shuts services down.
+type signalHandler struct {
+	// signal is the channel to which OS signals are sent.
+	signal chan os.Signal
+
+	// confFile is the path to the configuration file.
+	confFile string
+
+	// start is the time at which AdGuard Home has been started.
+	start time.Time
+
+	// services are the services that are shut down before application exiting.
+	services []agh.Service
+}
+
+// handle processes OS signals.
+func (h *signalHandler) handle() {
+	defer log.OnPanic("signalHandler.handle")
+
+	for sig := range h.signal {
+		log.Info("sighdlr: received signal %q", sig)
+
+		if aghos.IsReconfigureSignal(sig) {
+			h.reconfigure()
+		} else if aghos.IsShutdownSignal(sig) {
+			status := h.shutdown()
+			log.Info("sighdlr: exiting with status %d", status)
+
+			os.Exit(status)
+		}
+	}
+}
+
+// reconfigure rereads the configuration file and updates and restarts services.
+func (h *signalHandler) reconfigure() {
+	log.Info("sighdlr: reconfiguring adguard home")
+
+	status := h.shutdown()
+	if status != statusSuccess {
+		log.Info("sighdlr: reconfiruging: exiting with status %d", status)
+
+		os.Exit(status)
+	}
+
+	// TODO(a.garipov): This is a very rough way to do it.  Some services can be
+	// reconfigured without the full shutdown, and the error handling is
+	// currently not the best.
+
+	confMgr, err := configmgr.New(h.confFile, h.start)
+	fatalOnError(err)
+
+	web := confMgr.Web()
+	err = web.Start()
+	fatalOnError(err)
+
+	dns := confMgr.DNS()
+	err = dns.Start()
+	fatalOnError(err)
+
+	h.services = []agh.Service{
+		dns,
+		web,
+	}
+
+	log.Info("sighdlr: successfully reconfigured adguard home")
+}
+
+// Exit status constants.
+const (
+	statusSuccess = 0
+	statusError   = 1
+)
+
+// shutdown gracefully shuts down all services.
+func (h *signalHandler) shutdown() (status int) {
+	ctx, cancel := ctxWithDefaultTimeout()
+	defer cancel()
+
+	status = statusSuccess
+
+	log.Info("sighdlr: shutting down services")
+	for i, service := range h.services {
+		err := service.Shutdown(ctx)
+		if err != nil {
+			log.Error("sighdlr: shutting down service at index %d: %s", i, err)
+			status = statusError
+		}
+	}
+
+	return status
+}
+
+// newSignalHandler returns a new signalHandler that shuts down svcs.
+func newSignalHandler(confFile string, start time.Time, svcs ...agh.Service) (h *signalHandler) {
+	h = &signalHandler{
+		signal:   make(chan os.Signal, 1),
+		confFile: confFile,
+		start:    start,
+		services: svcs,
+	}
+
+	aghos.NotifyShutdownSignal(h.signal)
+	aghos.NotifyReconfigureSignal(h.signal)
+
+	return h
+}

internal/next/configmgr/config.go

@@ -0,0 +1,40 @@
+package configmgr
+
+import (
+	"net/netip"
+
+	"github.com/AdguardTeam/golibs/timeutil"
+)
+
+// Configuration Structures
+
+// config is the top-level on-disk configuration structure.
+type config struct {
+	DNS  *dnsConfig  `yaml:"dns"`
+	HTTP *httpConfig `yaml:"http"`
+	// TODO(a.garipov): Use.
+	SchemaVersion int `yaml:"schema_version"`
+	// TODO(a.garipov): Use.
+	DebugPprof bool `yaml:"debug_pprof"`
+	Verbose    bool `yaml:"verbose"`
+}
+
+// dnsConfig is the on-disk DNS configuration.
+//
+// TODO(a.garipov): Validate.
+type dnsConfig struct {
+	Addresses       []netip.AddrPort  `yaml:"addresses"`
+	BootstrapDNS    []string          `yaml:"bootstrap_dns"`
+	UpstreamDNS     []string          `yaml:"upstream_dns"`
+	UpstreamTimeout timeutil.Duration `yaml:"upstream_timeout"`
+}
+
+// httpConfig is the on-disk web API configuration.
+//
+// TODO(a.garipov): Validate.
+type httpConfig struct {
+	Addresses       []netip.AddrPort  `yaml:"addresses"`
+	SecureAddresses []netip.AddrPort  `yaml:"secure_addresses"`
+	Timeout         timeutil.Duration `yaml:"timeout"`
+	ForceHTTPS      bool              `yaml:"force_https"`
+}

internal/next/configmgr/configmgr.go

@@ -0,0 +1,205 @@
+// Package configmgr defines the AdGuard Home on-disk configuration entities and
+// configuration manager.
+package configmgr
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/AdguardTeam/golibs/errors"
+	"github.com/AdguardTeam/golibs/log"
+	"gopkg.in/yaml.v3"
+)
+
+// Configuration Manager
+
+// Manager handles full and partial changes in the configuration, persisting
+// them to disk if necessary.
+type Manager struct {
+	// updMu makes sure that at most one reconfiguration is performed at a time.
+	// updMu protects all fields below.
+	updMu *sync.RWMutex
+
+	// dns is the DNS service.
+	dns *dnssvc.Service
+
+	// Web is the Web API service.
+	web *websvc.Service
+
+	// current is the current configuration.
+	current *config
+
+	// fileName is the name of the configuration file.
+	fileName string
+}
+
+// New creates a new *Manager that persists changes to the file pointed to by
+// fileName.  It reads the configuration file and populates the service fields.
+// start is the startup time of AdGuard Home.
+func New(fileName string, start time.Time) (m *Manager, err error) {
+	defer func() { err = errors.Annotate(err, "reading config") }()
+
+	conf := &config{}
+	f, err := os.Open(fileName)
+	if err != nil {
+		// Don't wrap the error, because it's informative enough as is.
+		return nil, err
+	}
+	defer func() { err = errors.WithDeferred(err, f.Close()) }()
+
+	err = yaml.NewDecoder(f).Decode(conf)
+	if err != nil {
+		// Don't wrap the error, because it's informative enough as is.
+		return nil, err
+	}
+
+	// TODO(a.garipov): Move into a separate function and add other logging
+	// settings.
+	if conf.Verbose {
+		log.SetLevel(log.DEBUG)
+	}
+
+	// TODO(a.garipov): Validate the configuration structure.  Return an error
+	// if it's incorrect.
+
+	m = &Manager{
+		updMu:    &sync.RWMutex{},
+		current:  conf,
+		fileName: fileName,
+	}
+
+	// TODO(a.garipov): Get the context with the timeout from the arguments?
+	const assemblyTimeout = 5 * time.Second
+	ctx, cancel := context.WithTimeout(context.Background(), assemblyTimeout)
+	defer cancel()
+
+	err = m.assemble(ctx, conf, start)
+	if err != nil {
+		// Don't wrap the error, because it's informative enough as is.
+		return nil, err
+	}
+
+	return m, nil
+}
+
+// assemble creates all services and puts them into the corresponding fields.
+// The fields of conf must not be modified after calling assemble.
+func (m *Manager) assemble(ctx context.Context, conf *config, start time.Time) (err error) {
+	dnsConf := &dnssvc.Config{
+		Addresses:        conf.DNS.Addresses,
+		BootstrapServers: conf.DNS.BootstrapDNS,
+		UpstreamServers:  conf.DNS.UpstreamDNS,
+		UpstreamTimeout:  conf.DNS.UpstreamTimeout.Duration,
+	}
+	err = m.updateDNS(ctx, dnsConf)
+	if err != nil {
+		return fmt.Errorf("assembling dnssvc: %w", err)
+	}
+
+	webSvcConf := &websvc.Config{
+		ConfigManager: m,
+		// TODO(a.garipov): Fill from config file.
+		TLS:             nil,
+		Start:           start,
+		Addresses:       conf.HTTP.Addresses,
+		SecureAddresses: conf.HTTP.SecureAddresses,
+		Timeout:         conf.HTTP.Timeout.Duration,
+		ForceHTTPS:      conf.HTTP.ForceHTTPS,
+	}
+
+	err = m.updateWeb(ctx, webSvcConf)
+	if err != nil {
+		return fmt.Errorf("assembling websvc: %w", err)
+	}
+
+	return nil
+}
+
+// DNS returns the current DNS service.  It is safe for concurrent use.
+func (m *Manager) DNS() (dns agh.ServiceWithConfig[*dnssvc.Config]) {
+	m.updMu.RLock()
+	defer m.updMu.RUnlock()
+
+	return m.dns
+}
+
+// UpdateDNS implements the [websvc.ConfigManager] interface for *Manager.  The
+// fields of c must not be modified after calling UpdateDNS.
+func (m *Manager) UpdateDNS(ctx context.Context, c *dnssvc.Config) (err error) {
+	m.updMu.Lock()
+	defer m.updMu.Unlock()
+
+	// TODO(a.garipov): Update and write the configuration file.  Return an
+	// error if something went wrong.
+
+	err = m.updateDNS(ctx, c)
+	if err != nil {
+		return fmt.Errorf("reassembling dnssvc: %w", err)
+	}
+
+	return nil
+}
+
+// updateDNS recreates the DNS service.  m.updMu is expected to be locked.
+func (m *Manager) updateDNS(ctx context.Context, c *dnssvc.Config) (err error) {
+	if prev := m.dns; prev != nil {
+		err = prev.Shutdown(ctx)
+		if err != nil {
+			return fmt.Errorf("shutting down dns svc: %w", err)
+		}
+	}
+
+	svc, err := dnssvc.New(c)
+	if err != nil {
+		return fmt.Errorf("creating dns svc: %w", err)
+	}
+
+	m.dns = svc
+
+	return nil
+}
+
+// Web returns the current web service.  It is safe for concurrent use.
+func (m *Manager) Web() (web agh.ServiceWithConfig[*websvc.Config]) {
+	m.updMu.RLock()
+	defer m.updMu.RUnlock()
+
+	return m.web
+}
+
+// UpdateWeb implements the [websvc.ConfigManager] interface for *Manager.  The
+// fields of c must not be modified after calling UpdateWeb.
+func (m *Manager) UpdateWeb(ctx context.Context, c *websvc.Config) (err error) {
+	m.updMu.Lock()
+	defer m.updMu.Unlock()
+
+	// TODO(a.garipov): Update and write the configuration file.  Return an
+	// error if something went wrong.
+
+	err = m.updateWeb(ctx, c)
+	if err != nil {
+		return fmt.Errorf("reassembling websvc: %w", err)
+	}
+
+	return nil
+}
+
+// updateWeb recreates the web service.  m.upd is expected to be locked.
+func (m *Manager) updateWeb(ctx context.Context, c *websvc.Config) (err error) {
+	if prev := m.web; prev != nil {
+		err = prev.Shutdown(ctx)
+		if err != nil {
+			return fmt.Errorf("shutting down web svc: %w", err)
+		}
+	}
+
+	m.web = websvc.New(c)
+
+	return nil
+}

internal/next/dnssvc/dnssvc.go

@@ -0,0 +1,227 @@
+// Package dnssvc contains the AdGuard Home DNS service.
+//
+// TODO(a.garipov): Define, if all methods of a *Service should work with a nil
+// receiver.
+package dnssvc
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"net/netip"
+	"sync/atomic"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	// TODO(a.garipov): Add a “dnsproxy proxy” package to shield us from changes
+	// and replacement of module dnsproxy.
+	"github.com/AdguardTeam/dnsproxy/proxy"
+	"github.com/AdguardTeam/dnsproxy/upstream"
+)
+
+// Config is the AdGuard Home DNS service configuration structure.
+//
+// TODO(a.garipov): Add timeout for incoming requests.
+type Config struct {
+	// Addresses are the addresses on which to serve plain DNS queries.
+	Addresses []netip.AddrPort
+
+	// Upstreams are the DNS upstreams to use.  If not set, upstreams are
+	// created using data from BootstrapServers, UpstreamServers, and
+	// UpstreamTimeout.
+	//
+	// TODO(a.garipov): Think of a better scheme.  Those other three parameters
+	// are here only to make Config work properly.
+	Upstreams []upstream.Upstream
+
+	// BootstrapServers are the addresses for bootstrapping the upstream DNS
+	// server addresses.
+	BootstrapServers []string
+
+	// UpstreamServers are the upstream DNS server addresses to use.
+	UpstreamServers []string
+
+	// UpstreamTimeout is the timeout for upstream requests.
+	UpstreamTimeout time.Duration
+}
+
+// Service is the AdGuard Home DNS service.  A nil *Service is a valid
+// [agh.Service] that does nothing.
+type Service struct {
+	// running is an atomic boolean value.  Keep it the first value in the
+	// struct to ensure atomic alignment.  0 means that the service is not
+	// running, 1 means that it is running.
+	//
+	// TODO(a.garipov): Use [atomic.Bool] in Go 1.19 or get rid of it
+	// completely.
+	running uint64
+
+	proxy      *proxy.Proxy
+	bootstraps []string
+	upstreams  []string
+	upsTimeout time.Duration
+}
+
+// New returns a new properly initialized *Service.  If c is nil, svc is a nil
+// *Service that does nothing.  The fields of c must not be modified after
+// calling New.
+func New(c *Config) (svc *Service, err error) {
+	if c == nil {
+		return nil, nil
+	}
+
+	svc = &Service{
+		bootstraps: c.BootstrapServers,
+		upstreams:  c.UpstreamServers,
+		upsTimeout: c.UpstreamTimeout,
+	}
+
+	var upstreams []upstream.Upstream
+	if len(c.Upstreams) > 0 {
+		upstreams = c.Upstreams
+	} else {
+		upstreams, err = addressesToUpstreams(
+			c.UpstreamServers,
+			c.BootstrapServers,
+			c.UpstreamTimeout,
+		)
+		if err != nil {
+			return nil, fmt.Errorf("converting upstreams: %w", err)
+		}
+	}
+
+	svc.proxy = &proxy.Proxy{
+		Config: proxy.Config{
+			UDPListenAddr: udpAddrs(c.Addresses),
+			TCPListenAddr: tcpAddrs(c.Addresses),
+			UpstreamConfig: &proxy.UpstreamConfig{
+				Upstreams: upstreams,
+			},
+		},
+	}
+
+	err = svc.proxy.Init()
+	if err != nil {
+		return nil, fmt.Errorf("proxy: %w", err)
+	}
+
+	return svc, nil
+}
+
+// addressesToUpstreams is a wrapper around [upstream.AddressToUpstream].  It
+// accepts a slice of addresses and other upstream parameters, and returns a
+// slice of upstreams.
+func addressesToUpstreams(
+	upsStrs []string,
+	bootstraps []string,
+	timeout time.Duration,
+) (upstreams []upstream.Upstream, err error) {
+	upstreams = make([]upstream.Upstream, len(upsStrs))
+	for i, upsStr := range upsStrs {
+		upstreams[i], err = upstream.AddressToUpstream(upsStr, &upstream.Options{
+			Bootstrap: bootstraps,
+			Timeout:   timeout,
+		})
+		if err != nil {
+			return nil, fmt.Errorf("upstream at index %d: %w", i, err)
+		}
+	}
+
+	return upstreams, nil
+}
+
+// tcpAddrs converts []netip.AddrPort into []*net.TCPAddr.
+func tcpAddrs(addrPorts []netip.AddrPort) (tcpAddrs []*net.TCPAddr) {
+	if addrPorts == nil {
+		return nil
+	}
+
+	tcpAddrs = make([]*net.TCPAddr, len(addrPorts))
+	for i, a := range addrPorts {
+		tcpAddrs[i] = net.TCPAddrFromAddrPort(a)
+	}
+
+	return tcpAddrs
+}
+
+// udpAddrs converts []netip.AddrPort into []*net.UDPAddr.
+func udpAddrs(addrPorts []netip.AddrPort) (udpAddrs []*net.UDPAddr) {
+	if addrPorts == nil {
+		return nil
+	}
+
+	udpAddrs = make([]*net.UDPAddr, len(addrPorts))
+	for i, a := range addrPorts {
+		udpAddrs[i] = net.UDPAddrFromAddrPort(a)
+	}
+
+	return udpAddrs
+}
+
+// type check
+var _ agh.Service = (*Service)(nil)
+
+// Start implements the [agh.Service] interface for *Service.  svc may be nil.
+// After Start exits, all DNS servers have tried to start, but there is no
+// guarantee that they did.  Errors from the servers are written to the log.
+func (svc *Service) Start() (err error) {
+	if svc == nil {
+		return nil
+	}
+
+	defer func() {
+		// TODO(a.garipov): [proxy.Proxy.Start] doesn't actually have any way to
+		// tell when all servers are actually up, so at best this is merely an
+		// assumption.
+		if err != nil {
+			atomic.StoreUint64(&svc.running, 0)
+		} else {
+			atomic.StoreUint64(&svc.running, 1)
+		}
+	}()
+
+	return svc.proxy.Start()
+}
+
+// Shutdown implements the [agh.Service] interface for *Service.  svc may be
+// nil.
+func (svc *Service) Shutdown(ctx context.Context) (err error) {
+	if svc == nil {
+		return nil
+	}
+
+	return svc.proxy.Stop()
+}
+
+// Config returns the current configuration of the web service.  Config must not
+// be called simultaneously with Start.  If svc was initialized with ":0"
+// addresses, addrs will not return the actual bound ports until Start is
+// finished.
+func (svc *Service) Config() (c *Config) {
+	// TODO(a.garipov): Do we need to get the TCP addresses separately?
+
+	var addrs []netip.AddrPort
+	if atomic.LoadUint64(&svc.running) == 1 {
+		udpAddrs := svc.proxy.Addrs(proxy.ProtoUDP)
+		addrs = make([]netip.AddrPort, len(udpAddrs))
+		for i, a := range udpAddrs {
+			addrs[i] = a.(*net.UDPAddr).AddrPort()
+		}
+	} else {
+		conf := svc.proxy.Config
+		udpAddrs := conf.UDPListenAddr
+		addrs = make([]netip.AddrPort, len(udpAddrs))
+		for i, a := range udpAddrs {
+			addrs[i] = a.AddrPort()
+		}
+	}
+
+	c = &Config{
+		Addresses:        addrs,
+		BootstrapServers: svc.bootstraps,
+		UpstreamServers:  svc.upstreams,
+		UpstreamTimeout:  svc.upsTimeout,
+	}
+
+	return c
+}

internal/next/dnssvc/dnssvc_test.go

@@ -0,0 +1,96 @@
+package dnssvc_test
+
+import (
+	"context"
+	"net/netip"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+	"github.com/AdguardTeam/dnsproxy/upstream"
+	"github.com/AdguardTeam/golibs/errors"
+	"github.com/AdguardTeam/golibs/testutil"
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMain(m *testing.M) {
+	testutil.DiscardLogOutput(m)
+}
+
+// testTimeout is the common timeout for tests.
+const testTimeout = 100 * time.Millisecond
+
+func TestService(t *testing.T) {
+	const (
+		bootstrapAddr = "bootstrap.example"
+		upstreamAddr  = "upstream.example"
+
+		closeErr errors.Error = "closing failed"
+	)
+
+	ups := &aghtest.UpstreamMock{
+		OnAddress: func() (addr string) {
+			return upstreamAddr
+		},
+		OnExchange: func(req *dns.Msg) (resp *dns.Msg, err error) {
+			resp = (&dns.Msg{}).SetReply(req)
+
+			return resp, nil
+		},
+		OnClose: func() (err error) {
+			return closeErr
+		},
+	}
+
+	c := &dnssvc.Config{
+		Addresses:        []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:0")},
+		Upstreams:        []upstream.Upstream{ups},
+		BootstrapServers: []string{bootstrapAddr},
+		UpstreamServers:  []string{upstreamAddr},
+		UpstreamTimeout:  testTimeout,
+	}
+
+	svc, err := dnssvc.New(c)
+	require.NoError(t, err)
+
+	err = svc.Start()
+	require.NoError(t, err)
+
+	gotConf := svc.Config()
+	require.NotNil(t, gotConf)
+	require.Len(t, gotConf.Addresses, 1)
+
+	addr := gotConf.Addresses[0]
+
+	t.Run("dns", func(t *testing.T) {
+		req := &dns.Msg{
+			MsgHdr: dns.MsgHdr{
+				Id:               dns.Id(),
+				RecursionDesired: true,
+			},
+			Question: []dns.Question{{
+				Name:   "example.com.",
+				Qtype:  dns.TypeA,
+				Qclass: dns.ClassINET,
+			}},
+		}
+
+		ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+		defer cancel()
+
+		cli := &dns.Client{}
+		resp, _, excErr := cli.ExchangeContext(ctx, req, addr.String())
+		require.NoError(t, excErr)
+
+		assert.NotNil(t, resp)
+	})
+
+	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+
+	err = svc.Shutdown(ctx)
+	require.ErrorIs(t, err, closeErr)
+}

internal/next/websvc/dns.go

@@ -0,0 +1,84 @@
+package websvc
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/netip"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+)
+
+// DNS Settings Handlers
+
+// ReqPatchSettingsDNS describes the request to the PATCH /api/v1/settings/dns
+// HTTP API.
+type ReqPatchSettingsDNS struct {
+	// TODO(a.garipov): Add more as we go.
+
+	Addresses        []netip.AddrPort `json:"addresses"`
+	BootstrapServers []string         `json:"bootstrap_servers"`
+	UpstreamServers  []string         `json:"upstream_servers"`
+	UpstreamTimeout  JSONDuration     `json:"upstream_timeout"`
+}
+
+// HTTPAPIDNSSettings are the DNS settings as used by the HTTP API.  See the
+// DnsSettings object in the OpenAPI specification.
+type HTTPAPIDNSSettings struct {
+	// TODO(a.garipov): Add more as we go.
+
+	Addresses        []netip.AddrPort `json:"addresses"`
+	BootstrapServers []string         `json:"bootstrap_servers"`
+	UpstreamServers  []string         `json:"upstream_servers"`
+	UpstreamTimeout  JSONDuration     `json:"upstream_timeout"`
+}
+
+// handlePatchSettingsDNS is the handler for the PATCH /api/v1/settings/dns HTTP
+// API.
+func (svc *Service) handlePatchSettingsDNS(w http.ResponseWriter, r *http.Request) {
+	req := &ReqPatchSettingsDNS{
+		Addresses:        []netip.AddrPort{},
+		BootstrapServers: []string{},
+		UpstreamServers:  []string{},
+	}
+
+	// TODO(a.garipov): Validate nulls and proper JSON patch.
+
+	err := json.NewDecoder(r.Body).Decode(&req)
+	if err != nil {
+		writeJSONErrorResponse(w, r, fmt.Errorf("decoding: %w", err))
+
+		return
+	}
+
+	newConf := &dnssvc.Config{
+		Addresses:        req.Addresses,
+		BootstrapServers: req.BootstrapServers,
+		UpstreamServers:  req.UpstreamServers,
+		UpstreamTimeout:  time.Duration(req.UpstreamTimeout),
+	}
+
+	ctx := r.Context()
+	err = svc.confMgr.UpdateDNS(ctx, newConf)
+	if err != nil {
+		writeJSONErrorResponse(w, r, fmt.Errorf("updating: %w", err))
+
+		return
+	}
+
+	newSvc := svc.confMgr.DNS()
+	err = newSvc.Start()
+	if err != nil {
+		writeJSONErrorResponse(w, r, fmt.Errorf("starting new service: %w", err))
+
+		return
+	}
+
+	writeJSONOKResponse(w, r, &HTTPAPIDNSSettings{
+		Addresses:        newConf.Addresses,
+		BootstrapServers: newConf.BootstrapServers,
+		UpstreamServers:  newConf.UpstreamServers,
+		UpstreamTimeout:  JSONDuration(newConf.UpstreamTimeout),
+	})
+}

internal/next/websvc/dns_test.go

@@ -0,0 +1,69 @@
+package websvc_test
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestService_HandlePatchSettingsDNS(t *testing.T) {
+	wantDNS := &websvc.HTTPAPIDNSSettings{
+		Addresses:        []netip.AddrPort{netip.MustParseAddrPort("127.0.1.1:53")},
+		BootstrapServers: []string{"1.0.0.1"},
+		UpstreamServers:  []string{"1.1.1.1"},
+		UpstreamTimeout:  websvc.JSONDuration(2 * time.Second),
+	}
+
+	// TODO(a.garipov): Use [atomic.Bool] in Go 1.19.
+	var numStarted uint64
+	confMgr := newConfigManager()
+	confMgr.onDNS = func() (s agh.ServiceWithConfig[*dnssvc.Config]) {
+		return &aghtest.ServiceWithConfig[*dnssvc.Config]{
+			OnStart: func() (err error) {
+				atomic.AddUint64(&numStarted, 1)
+
+				return nil
+			},
+			OnShutdown: func(_ context.Context) (err error) { panic("not implemented") },
+			OnConfig:   func() (c *dnssvc.Config) { panic("not implemented") },
+		}
+	}
+	confMgr.onUpdateDNS = func(ctx context.Context, c *dnssvc.Config) (err error) {
+		return nil
+	}
+
+	_, addr := newTestServer(t, confMgr)
+	u := &url.URL{
+		Scheme: "http",
+		Host:   addr.String(),
+		Path:   websvc.PathV1SettingsDNS,
+	}
+
+	req := jobj{
+		"addresses":         wantDNS.Addresses,
+		"bootstrap_servers": wantDNS.BootstrapServers,
+		"upstream_servers":  wantDNS.UpstreamServers,
+		"upstream_timeout":  wantDNS.UpstreamTimeout,
+	}
+
+	respBody := httpPatch(t, u, req, http.StatusOK)
+	resp := &websvc.HTTPAPIDNSSettings{}
+	err := json.Unmarshal(respBody, resp)
+	require.NoError(t, err)
+
+	assert.Equal(t, uint64(1), numStarted)
+	assert.Equal(t, wantDNS, resp)
+	assert.Equal(t, wantDNS, resp)
+}

internal/next/websvc/http.go

@@ -0,0 +1,110 @@
+package websvc
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/netip"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+// HTTP Settings Handlers
+
+// ReqPatchSettingsHTTP describes the request to the PATCH /api/v1/settings/http
+// HTTP API.
+type ReqPatchSettingsHTTP struct {
+	// TODO(a.garipov): Add more as we go.
+	//
+	// TODO(a.garipov): Add wait time.
+
+	Addresses       []netip.AddrPort `json:"addresses"`
+	SecureAddresses []netip.AddrPort `json:"secure_addresses"`
+	Timeout         JSONDuration     `json:"timeout"`
+}
+
+// HTTPAPIHTTPSettings are the HTTP settings as used by the HTTP API.  See the
+// HttpSettings object in the OpenAPI specification.
+type HTTPAPIHTTPSettings struct {
+	// TODO(a.garipov): Add more as we go.
+
+	Addresses       []netip.AddrPort `json:"addresses"`
+	SecureAddresses []netip.AddrPort `json:"secure_addresses"`
+	Timeout         JSONDuration     `json:"timeout"`
+	ForceHTTPS      bool             `json:"force_https"`
+}
+
+// handlePatchSettingsHTTP is the handler for the PATCH /api/v1/settings/http
+// HTTP API.
+func (svc *Service) handlePatchSettingsHTTP(w http.ResponseWriter, r *http.Request) {
+	req := &ReqPatchSettingsHTTP{}
+
+	// TODO(a.garipov): Validate nulls and proper JSON patch.
+
+	err := json.NewDecoder(r.Body).Decode(&req)
+	if err != nil {
+		writeJSONErrorResponse(w, r, fmt.Errorf("decoding: %w", err))
+
+		return
+	}
+
+	newConf := &Config{
+		ConfigManager:   svc.confMgr,
+		TLS:             svc.tls,
+		Addresses:       req.Addresses,
+		SecureAddresses: req.SecureAddresses,
+		Timeout:         time.Duration(req.Timeout),
+		ForceHTTPS:      svc.forceHTTPS,
+	}
+
+	writeJSONOKResponse(w, r, &HTTPAPIHTTPSettings{
+		Addresses:       newConf.Addresses,
+		SecureAddresses: newConf.SecureAddresses,
+		Timeout:         JSONDuration(newConf.Timeout),
+		ForceHTTPS:      newConf.ForceHTTPS,
+	})
+
+	cancelUpd := func() {}
+	updCtx := context.Background()
+
+	ctx := r.Context()
+	if deadline, ok := ctx.Deadline(); ok {
+		updCtx, cancelUpd = context.WithDeadline(updCtx, deadline)
+	}
+
+	// Launch the new HTTP service in a separate goroutine to let this handler
+	// finish and thus, this server to shutdown.
+	go func() {
+		defer cancelUpd()
+
+		updErr := svc.confMgr.UpdateWeb(updCtx, newConf)
+		if updErr != nil {
+			writeJSONErrorResponse(w, r, fmt.Errorf("updating: %w", updErr))
+
+			return
+		}
+
+		// TODO(a.garipov): Consider better ways to do this.
+		const maxUpdDur = 10 * time.Second
+		updStart := time.Now()
+		var newSvc agh.ServiceWithConfig[*Config]
+		for newSvc = svc.confMgr.Web(); newSvc == svc; {
+			if time.Since(updStart) >= maxUpdDur {
+				log.Error("websvc: failed to update svc after %s", maxUpdDur)
+
+				return
+			}
+
+			log.Debug("websvc: waiting for new websvc to be configured")
+			time.Sleep(1 * time.Second)
+		}
+
+		updErr = newSvc.Start()
+		if updErr != nil {
+			log.Error("websvc: new svc failed to start with error: %s", updErr)
+		}
+	}()
+}

internal/next/websvc/http_test.go

@@ -0,0 +1,63 @@
+package websvc_test
+
+import (
+	"context"
+	"crypto/tls"
+	"encoding/json"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestService_HandlePatchSettingsHTTP(t *testing.T) {
+	wantWeb := &websvc.HTTPAPIHTTPSettings{
+		Addresses:       []netip.AddrPort{netip.MustParseAddrPort("127.0.1.1:80")},
+		SecureAddresses: []netip.AddrPort{netip.MustParseAddrPort("127.0.1.1:443")},
+		Timeout:         websvc.JSONDuration(10 * time.Second),
+		ForceHTTPS:      false,
+	}
+
+	confMgr := newConfigManager()
+	confMgr.onWeb = func() (s agh.ServiceWithConfig[*websvc.Config]) {
+		return websvc.New(&websvc.Config{
+			TLS: &tls.Config{
+				Certificates: []tls.Certificate{{}},
+			},
+			Addresses:       []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:80")},
+			SecureAddresses: []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:443")},
+			Timeout:         5 * time.Second,
+			ForceHTTPS:      true,
+		})
+	}
+	confMgr.onUpdateWeb = func(ctx context.Context, c *websvc.Config) (err error) {
+		return nil
+	}
+
+	_, addr := newTestServer(t, confMgr)
+	u := &url.URL{
+		Scheme: "http",
+		Host:   addr.String(),
+		Path:   websvc.PathV1SettingsHTTP,
+	}
+
+	req := jobj{
+		"addresses":        wantWeb.Addresses,
+		"secure_addresses": wantWeb.SecureAddresses,
+		"timeout":          wantWeb.Timeout,
+		"force_https":      wantWeb.ForceHTTPS,
+	}
+
+	respBody := httpPatch(t, u, req, http.StatusOK)
+	resp := &websvc.HTTPAPIHTTPSettings{}
+	err := json.Unmarshal(respBody, resp)
+	require.NoError(t, err)
+
+	assert.Equal(t, wantWeb, resp)
+}

internal/next/websvc/json.go

@@ -0,0 +1,143 @@
+package websvc
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+// JSON Utilities
+
+// nsecPerMsec is the number of nanoseconds in a millisecond.
+const nsecPerMsec = float64(time.Millisecond / time.Nanosecond)
+
+// JSONDuration is a time.Duration that can be decoded from JSON and encoded
+// into JSON according to our API conventions.
+type JSONDuration time.Duration
+
+// type check
+var _ json.Marshaler = JSONDuration(0)
+
+// MarshalJSON implements the json.Marshaler interface for JSONDuration.  err is
+// always nil.
+func (d JSONDuration) MarshalJSON() (b []byte, err error) {
+	msec := float64(time.Duration(d)) / nsecPerMsec
+	b = strconv.AppendFloat(nil, msec, 'f', -1, 64)
+
+	return b, nil
+}
+
+// type check
+var _ json.Unmarshaler = (*JSONDuration)(nil)
+
+// UnmarshalJSON implements the json.Marshaler interface for *JSONDuration.
+func (d *JSONDuration) UnmarshalJSON(b []byte) (err error) {
+	if d == nil {
+		return fmt.Errorf("json duration is nil")
+	}
+
+	msec, err := strconv.ParseFloat(string(b), 64)
+	if err != nil {
+		return fmt.Errorf("parsing json time: %w", err)
+	}
+
+	*d = JSONDuration(int64(msec * nsecPerMsec))
+
+	return nil
+}
+
+// JSONTime is a time.Time that can be decoded from JSON and encoded into JSON
+// according to our API conventions.
+type JSONTime time.Time
+
+// type check
+var _ json.Marshaler = JSONTime{}
+
+// MarshalJSON implements the json.Marshaler interface for JSONTime.  err is
+// always nil.
+func (t JSONTime) MarshalJSON() (b []byte, err error) {
+	msec := float64(time.Time(t).UnixNano()) / nsecPerMsec
+	b = strconv.AppendFloat(nil, msec, 'f', -1, 64)
+
+	return b, nil
+}
+
+// type check
+var _ json.Unmarshaler = (*JSONTime)(nil)
+
+// UnmarshalJSON implements the json.Marshaler interface for *JSONTime.
+func (t *JSONTime) UnmarshalJSON(b []byte) (err error) {
+	if t == nil {
+		return fmt.Errorf("json time is nil")
+	}
+
+	msec, err := strconv.ParseFloat(string(b), 64)
+	if err != nil {
+		return fmt.Errorf("parsing json time: %w", err)
+	}
+
+	*t = JSONTime(time.Unix(0, int64(msec*nsecPerMsec)).UTC())
+
+	return nil
+}
+
+// writeJSONOKResponse writes headers with the code 200 OK, encodes v into w,
+// and logs any errors it encounters.  r is used to get additional information
+// from the request.
+func writeJSONOKResponse(w http.ResponseWriter, r *http.Request, v any) {
+	writeJSONResponse(w, r, v, http.StatusOK)
+}
+
+// writeJSONResponse writes headers with code, encodes v into w, and logs any
+// errors it encounters.  r is used to get additional information from the
+// request.
+func writeJSONResponse(w http.ResponseWriter, r *http.Request, v any, code int) {
+	// TODO(a.garipov): Put some of these to a middleware.
+	h := w.Header()
+	h.Set(aghhttp.HdrNameContentType, aghhttp.HdrValApplicationJSON)
+	h.Set(aghhttp.HdrNameServer, aghhttp.UserAgent())
+
+	w.WriteHeader(code)
+
+	err := json.NewEncoder(w).Encode(v)
+	if err != nil {
+		log.Error("websvc: writing resp to %s %s: %s", r.Method, r.URL.Path, err)
+	}
+}
+
+// ErrorCode is the error code as used by the HTTP API.  See the ErrorCode
+// definition in the OpenAPI specification.
+type ErrorCode string
+
+// ErrorCode constants.
+//
+// TODO(a.garipov): Expand and document codes.
+const (
+	// ErrorCodeTMP000 is the temporary error code used for all errors.
+	ErrorCodeTMP000 = ""
+)
+
+// HTTPAPIErrorResp is the error response as used by the HTTP API.  See the
+// BadRequestResp, InternalServerErrorResp, and similar objects in the OpenAPI
+// specification.
+type HTTPAPIErrorResp struct {
+	Code ErrorCode `json:"code"`
+	Msg  string    `json:"msg"`
+}
+
+// writeJSONErrorResponse encodes err as a JSON error into w, and logs any
+// errors it encounters.  r is used to get additional information from the
+// request.
+func writeJSONErrorResponse(w http.ResponseWriter, r *http.Request, err error) {
+	log.Error("websvc: %s %s: %s", r.Method, r.URL.Path, err)
+
+	writeJSONResponse(w, r, &HTTPAPIErrorResp{
+		Code: ErrorCodeTMP000,
+		Msg:  err.Error(),
+	}, http.StatusUnprocessableEntity)
+}

internal/next/websvc/json_test.go

@@ -0,0 +1,114 @@
+package websvc_test
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/AdguardTeam/golibs/testutil"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// testJSONTime is the JSON time for tests.
+var testJSONTime = websvc.JSONTime(time.Unix(1_234_567_890, 123_456_000).UTC())
+
+// testJSONTimeStr is the string with the JSON encoding of testJSONTime.
+const testJSONTimeStr = "1234567890123.456"
+
+func TestJSONTime_MarshalJSON(t *testing.T) {
+	testCases := []struct {
+		name       string
+		wantErrMsg string
+		in         websvc.JSONTime
+		want       []byte
+	}{{
+		name:       "unix_zero",
+		wantErrMsg: "",
+		in:         websvc.JSONTime(time.Unix(0, 0)),
+		want:       []byte("0"),
+	}, {
+		name:       "empty",
+		wantErrMsg: "",
+		in:         websvc.JSONTime{},
+		want:       []byte("-6795364578871.345"),
+	}, {
+		name:       "time",
+		wantErrMsg: "",
+		in:         testJSONTime,
+		want:       []byte(testJSONTimeStr),
+	}}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := tc.in.MarshalJSON()
+			testutil.AssertErrorMsg(t, tc.wantErrMsg, err)
+
+			assert.Equal(t, tc.want, got)
+		})
+	}
+
+	t.Run("json", func(t *testing.T) {
+		in := &struct {
+			A websvc.JSONTime
+		}{
+			A: testJSONTime,
+		}
+
+		got, err := json.Marshal(in)
+		require.NoError(t, err)
+
+		assert.Equal(t, []byte(`{"A":`+testJSONTimeStr+`}`), got)
+	})
+}
+
+func TestJSONTime_UnmarshalJSON(t *testing.T) {
+	testCases := []struct {
+		name       string
+		wantErrMsg string
+		want       websvc.JSONTime
+		data       []byte
+	}{{
+		name:       "time",
+		wantErrMsg: "",
+		want:       testJSONTime,
+		data:       []byte(testJSONTimeStr),
+	}, {
+		name: "bad",
+		wantErrMsg: `parsing json time: strconv.ParseFloat: parsing "{}": ` +
+			`invalid syntax`,
+		want: websvc.JSONTime{},
+		data: []byte(`{}`),
+	}}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			var got websvc.JSONTime
+			err := got.UnmarshalJSON(tc.data)
+			testutil.AssertErrorMsg(t, tc.wantErrMsg, err)
+
+			assert.Equal(t, tc.want, got)
+		})
+	}
+
+	t.Run("nil", func(t *testing.T) {
+		err := (*websvc.JSONTime)(nil).UnmarshalJSON([]byte("0"))
+		require.Error(t, err)
+
+		msg := err.Error()
+		assert.Equal(t, "json time is nil", msg)
+	})
+
+	t.Run("json", func(t *testing.T) {
+		want := testJSONTime
+		var got struct {
+			A websvc.JSONTime
+		}
+
+		err := json.Unmarshal([]byte(`{"A":`+testJSONTimeStr+`}`), &got)
+		require.NoError(t, err)
+
+		assert.Equal(t, want, got.A)
+	})
+}

internal/next/websvc/middleware.go

@@ -0,0 +1,16 @@
+package websvc
+
+import "net/http"
+
+// Middlewares
+
+// jsonMw sets the content type of the response to application/json.
+func jsonMw(h http.Handler) (wrapped http.HandlerFunc) {
+	f := func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+
+		h.ServeHTTP(w, r)
+	}
+
+	return http.HandlerFunc(f)
+}

internal/next/websvc/path.go

@@ -0,0 +1,11 @@
+package websvc
+
+// Path constants
+const (
+	PathHealthCheck = "/health-check"
+
+	PathV1SettingsAll  = "/api/v1/settings/all"
+	PathV1SettingsDNS  = "/api/v1/settings/dns"
+	PathV1SettingsHTTP = "/api/v1/settings/http"
+	PathV1SystemInfo   = "/api/v1/system/info"
+)

internal/next/websvc/settings.go

@@ -0,0 +1,42 @@
+package websvc
+
+import (
+	"net/http"
+)
+
+// All Settings Handlers
+
+// RespGetV1SettingsAll describes the response of the GET /api/v1/settings/all
+// HTTP API.
+type RespGetV1SettingsAll struct {
+	// TODO(a.garipov): Add more as we go.
+
+	DNS  *HTTPAPIDNSSettings  `json:"dns"`
+	HTTP *HTTPAPIHTTPSettings `json:"http"`
+}
+
+// handleGetSettingsAll is the handler for the GET /api/v1/settings/all HTTP
+// API.
+func (svc *Service) handleGetSettingsAll(w http.ResponseWriter, r *http.Request) {
+	dnsSvc := svc.confMgr.DNS()
+	dnsConf := dnsSvc.Config()
+
+	webSvc := svc.confMgr.Web()
+	httpConf := webSvc.Config()
+
+	// TODO(a.garipov): Add all currently supported parameters.
+	writeJSONOKResponse(w, r, &RespGetV1SettingsAll{
+		DNS: &HTTPAPIDNSSettings{
+			Addresses:        dnsConf.Addresses,
+			BootstrapServers: dnsConf.BootstrapServers,
+			UpstreamServers:  dnsConf.UpstreamServers,
+			UpstreamTimeout:  JSONDuration(dnsConf.UpstreamTimeout),
+		},
+		HTTP: &HTTPAPIHTTPSettings{
+			Addresses:       httpConf.Addresses,
+			SecureAddresses: httpConf.SecureAddresses,
+			Timeout:         JSONDuration(httpConf.Timeout),
+			ForceHTTPS:      httpConf.ForceHTTPS,
+		},
+	})
+}

internal/next/websvc/settings_test.go

@@ -0,0 +1,75 @@
+package websvc_test
+
+import (
+	"crypto/tls"
+	"encoding/json"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestService_HandleGetSettingsAll(t *testing.T) {
+	// TODO(a.garipov): Add all currently supported parameters.
+
+	wantDNS := &websvc.HTTPAPIDNSSettings{
+		Addresses:        []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:53")},
+		BootstrapServers: []string{"94.140.14.140", "94.140.14.141"},
+		UpstreamServers:  []string{"94.140.14.14", "1.1.1.1"},
+		UpstreamTimeout:  websvc.JSONDuration(1 * time.Second),
+	}
+
+	wantWeb := &websvc.HTTPAPIHTTPSettings{
+		Addresses:       []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:80")},
+		SecureAddresses: []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:443")},
+		Timeout:         websvc.JSONDuration(5 * time.Second),
+		ForceHTTPS:      true,
+	}
+
+	confMgr := newConfigManager()
+	confMgr.onDNS = func() (s agh.ServiceWithConfig[*dnssvc.Config]) {
+		c, err := dnssvc.New(&dnssvc.Config{
+			Addresses:        wantDNS.Addresses,
+			UpstreamServers:  wantDNS.UpstreamServers,
+			BootstrapServers: wantDNS.BootstrapServers,
+			UpstreamTimeout:  time.Duration(wantDNS.UpstreamTimeout),
+		})
+		require.NoError(t, err)
+
+		return c
+	}
+
+	confMgr.onWeb = func() (s agh.ServiceWithConfig[*websvc.Config]) {
+		return websvc.New(&websvc.Config{
+			TLS: &tls.Config{
+				Certificates: []tls.Certificate{{}},
+			},
+			Addresses:       wantWeb.Addresses,
+			SecureAddresses: wantWeb.SecureAddresses,
+			Timeout:         time.Duration(wantWeb.Timeout),
+			ForceHTTPS:      true,
+		})
+	}
+
+	_, addr := newTestServer(t, confMgr)
+	u := &url.URL{
+		Scheme: "http",
+		Host:   addr.String(),
+		Path:   websvc.PathV1SettingsAll,
+	}
+
+	body := httpGet(t, u, http.StatusOK)
+	resp := &websvc.RespGetV1SettingsAll{}
+	err := json.Unmarshal(body, resp)
+	require.NoError(t, err)
+
+	assert.Equal(t, wantDNS, resp.DNS)
+	assert.Equal(t, wantWeb, resp.HTTP)
+}

internal/next/websvc/system.go

@@ -0,0 +1,35 @@
+package websvc
+
+import (
+	"net/http"
+	"runtime"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/version"
+)
+
+// System Handlers
+
+// RespGetV1SystemInfo describes the response of the GET /api/v1/system/info
+// HTTP API.
+type RespGetV1SystemInfo struct {
+	Arch       string   `json:"arch"`
+	Channel    string   `json:"channel"`
+	OS         string   `json:"os"`
+	NewVersion string   `json:"new_version,omitempty"`
+	Start      JSONTime `json:"start"`
+	Version    string   `json:"version"`
+}
+
+// handleGetV1SystemInfo is the handler for the GET /api/v1/system/info HTTP
+// API.
+func (svc *Service) handleGetV1SystemInfo(w http.ResponseWriter, r *http.Request) {
+	writeJSONOKResponse(w, r, &RespGetV1SystemInfo{
+		Arch:    runtime.GOARCH,
+		Channel: version.Channel(),
+		OS:      runtime.GOOS,
+		// TODO(a.garipov): Fill this when we have an updater.
+		NewVersion: "",
+		Start:      JSONTime(svc.start),
+		Version:    version.Version(),
+	})
+}

internal/next/websvc/system_test.go

@@ -0,0 +1,37 @@
+package websvc_test
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/url"
+	"runtime"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestService_handleGetV1SystemInfo(t *testing.T) {
+	confMgr := newConfigManager()
+	_, addr := newTestServer(t, confMgr)
+	u := &url.URL{
+		Scheme: "http",
+		Host:   addr.String(),
+		Path:   websvc.PathV1SystemInfo,
+	}
+
+	body := httpGet(t, u, http.StatusOK)
+	resp := &websvc.RespGetV1SystemInfo{}
+	err := json.Unmarshal(body, resp)
+	require.NoError(t, err)
+
+	// TODO(a.garipov): Consider making version.Channel and version.Version
+	// testable and test these better.
+	assert.NotEmpty(t, resp.Channel)
+
+	assert.Equal(t, resp.Arch, runtime.GOARCH)
+	assert.Equal(t, resp.OS, runtime.GOOS)
+	assert.Equal(t, testStart, time.Time(resp.Start))
+}

internal/next/websvc/waitlistener.go

@@ -0,0 +1,31 @@
+package websvc
+
+import (
+	"net"
+	"sync"
+)
+
+// Wait Listener
+
+// waitListener is a wrapper around a listener that also calls wg.Done() on the
+// first call to Accept.  It is useful in situations where it is important to
+// catch the precise moment of the first call to Accept, for example when
+// starting an HTTP server.
+//
+// TODO(a.garipov): Move to aghnet?
+type waitListener struct {
+	net.Listener
+
+	firstAcceptWG   *sync.WaitGroup
+	firstAcceptOnce sync.Once
+}
+
+// type check
+var _ net.Listener = (*waitListener)(nil)
+
+// Accept implements the [net.Listener] interface for *waitListener.
+func (l *waitListener) Accept() (conn net.Conn, err error) {
+	l.firstAcceptOnce.Do(l.firstAcceptWG.Done)
+
+	return l.Listener.Accept()
+}

internal/next/websvc/waitlistener_internal_test.go

@@ -0,0 +1,46 @@
+package websvc
+
+import (
+	"net"
+	"sync"
+	"sync/atomic"
+	"testing"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghchan"
+	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWaitListener_Accept(t *testing.T) {
+	// TODO(a.garipov): use atomic.Bool in Go 1.19.
+	var numAcceptCalls uint32
+	var l net.Listener = &aghtest.Listener{
+		OnAccept: func() (conn net.Conn, err error) {
+			atomic.AddUint32(&numAcceptCalls, 1)
+
+			return nil, nil
+		},
+		OnAddr:  func() (addr net.Addr) { panic("not implemented") },
+		OnClose: func() (err error) { panic("not implemented") },
+	}
+
+	wg := &sync.WaitGroup{}
+	wg.Add(1)
+
+	done := make(chan struct{})
+	go aghchan.MustReceive(done, testTimeout)
+
+	go func() {
+		var wrapper net.Listener = &waitListener{
+			Listener:      l,
+			firstAcceptWG: wg,
+		}
+
+		_, _ = wrapper.Accept()
+	}()
+
+	wg.Wait()
+	close(done)
+
+	assert.Equal(t, uint32(1), atomic.LoadUint32(&numAcceptCalls))
+}

internal/next/websvc/websvc.go

@@ -0,0 +1,305 @@
+// Package websvc contains the AdGuard Home HTTP API service.
+//
+// NOTE: Packages other than cmd must not import this package, as it imports
+// most other packages.
+//
+// TODO(a.garipov): Add tests.
+package websvc
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/netip"
+	"sync"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+	"github.com/AdguardTeam/golibs/errors"
+	"github.com/AdguardTeam/golibs/log"
+	httptreemux "github.com/dimfeld/httptreemux/v5"
+)
+
+// ConfigManager is the configuration manager interface.
+type ConfigManager interface {
+	DNS() (svc agh.ServiceWithConfig[*dnssvc.Config])
+	Web() (svc agh.ServiceWithConfig[*Config])
+
+	UpdateDNS(ctx context.Context, c *dnssvc.Config) (err error)
+	UpdateWeb(ctx context.Context, c *Config) (err error)
+}
+
+// Config is the AdGuard Home web service configuration structure.
+type Config struct {
+	// ConfigManager is used to show information about services as well as
+	// dynamically reconfigure them.
+	ConfigManager ConfigManager
+
+	// TLS is the optional TLS configuration.  If TLS is not nil,
+	// SecureAddresses must not be empty.
+	TLS *tls.Config
+
+	// Start is the time of start of AdGuard Home.
+	Start time.Time
+
+	// Addresses are the addresses on which to serve the plain HTTP API.
+	Addresses []netip.AddrPort
+
+	// SecureAddresses are the addresses on which to serve the HTTPS API.  If
+	// SecureAddresses is not empty, TLS must not be nil.
+	SecureAddresses []netip.AddrPort
+
+	// Timeout is the timeout for all server operations.
+	Timeout time.Duration
+
+	// ForceHTTPS tells if all requests to Addresses should be redirected to a
+	// secure address instead.
+	//
+	// TODO(a.garipov): Use; define rules, which address to redirect to.
+	ForceHTTPS bool
+}
+
+// Service is the AdGuard Home web service.  A nil *Service is a valid
+// [agh.Service] that does nothing.
+type Service struct {
+	confMgr    ConfigManager
+	tls        *tls.Config
+	start      time.Time
+	servers    []*http.Server
+	timeout    time.Duration
+	forceHTTPS bool
+}
+
+// New returns a new properly initialized *Service.  If c is nil, svc is a nil
+// *Service that does nothing.  The fields of c must not be modified after
+// calling New.
+func New(c *Config) (svc *Service) {
+	if c == nil {
+		return nil
+	}
+
+	svc = &Service{
+		confMgr:    c.ConfigManager,
+		tls:        c.TLS,
+		start:      c.Start,
+		timeout:    c.Timeout,
+		forceHTTPS: c.ForceHTTPS,
+	}
+
+	mux := newMux(svc)
+
+	for _, a := range c.Addresses {
+		addr := a.String()
+		errLog := log.StdLog("websvc: plain http: "+addr, log.ERROR)
+		svc.servers = append(svc.servers, &http.Server{
+			Addr:              addr,
+			Handler:           mux,
+			ErrorLog:          errLog,
+			ReadTimeout:       c.Timeout,
+			WriteTimeout:      c.Timeout,
+			IdleTimeout:       c.Timeout,
+			ReadHeaderTimeout: c.Timeout,
+		})
+	}
+
+	for _, a := range c.SecureAddresses {
+		addr := a.String()
+		errLog := log.StdLog("websvc: https: "+addr, log.ERROR)
+		svc.servers = append(svc.servers, &http.Server{
+			Addr:              addr,
+			Handler:           mux,
+			TLSConfig:         c.TLS,
+			ErrorLog:          errLog,
+			ReadTimeout:       c.Timeout,
+			WriteTimeout:      c.Timeout,
+			IdleTimeout:       c.Timeout,
+			ReadHeaderTimeout: c.Timeout,
+		})
+	}
+
+	return svc
+}
+
+// newMux returns a new HTTP request multiplexor for the AdGuard Home web
+// service.
+func newMux(svc *Service) (mux *httptreemux.ContextMux) {
+	mux = httptreemux.NewContextMux()
+
+	routes := []struct {
+		handler http.HandlerFunc
+		method  string
+		path    string
+		isJSON  bool
+	}{{
+		handler: svc.handleGetHealthCheck,
+		method:  http.MethodGet,
+		path:    PathHealthCheck,
+		isJSON:  false,
+	}, {
+		handler: svc.handleGetSettingsAll,
+		method:  http.MethodGet,
+		path:    PathV1SettingsAll,
+		isJSON:  true,
+	}, {
+		handler: svc.handlePatchSettingsDNS,
+		method:  http.MethodPatch,
+		path:    PathV1SettingsDNS,
+		isJSON:  true,
+	}, {
+		handler: svc.handlePatchSettingsHTTP,
+		method:  http.MethodPatch,
+		path:    PathV1SettingsHTTP,
+		isJSON:  true,
+	}, {
+		handler: svc.handleGetV1SystemInfo,
+		method:  http.MethodGet,
+		path:    PathV1SystemInfo,
+		isJSON:  true,
+	}}
+
+	for _, r := range routes {
+		if r.isJSON {
+			mux.Handle(r.method, r.path, jsonMw(r.handler))
+		} else {
+			mux.Handle(r.method, r.path, r.handler)
+		}
+	}
+
+	return mux
+}
+
+// addrs returns all addresses on which this server serves the HTTP API.  addrs
+// must not be called simultaneously with Start.  If svc was initialized with
+// ":0" addresses, addrs will not return the actual bound ports until Start is
+// finished.
+func (svc *Service) addrs() (addrs, secureAddrs []netip.AddrPort) {
+	for _, srv := range svc.servers {
+		addrPort, err := netip.ParseAddrPort(srv.Addr)
+		if err != nil {
+			// Technically shouldn't happen, since all servers must have a valid
+			// address.
+			panic(fmt.Errorf("websvc: server %q: bad address: %w", srv.Addr, err))
+		}
+
+		// srv.Serve will set TLSConfig to an almost empty value, so, instead of
+		// relying only on the nilness of TLSConfig, check the length of the
+		// certificates field as well.
+		if srv.TLSConfig == nil || len(srv.TLSConfig.Certificates) == 0 {
+			addrs = append(addrs, addrPort)
+		} else {
+			secureAddrs = append(secureAddrs, addrPort)
+		}
+
+	}
+
+	return addrs, secureAddrs
+}
+
+// handleGetHealthCheck is the handler for the GET /health-check HTTP API.
+func (svc *Service) handleGetHealthCheck(w http.ResponseWriter, _ *http.Request) {
+	_, _ = io.WriteString(w, "OK")
+}
+
+// type check
+var _ agh.Service = (*Service)(nil)
+
+// Start implements the [agh.Service] interface for *Service.  svc may be nil.
+// After Start exits, all HTTP servers have tried to start, possibly failing and
+// writing error messages to the log.
+func (svc *Service) Start() (err error) {
+	if svc == nil {
+		return nil
+	}
+
+	wg := &sync.WaitGroup{}
+	wg.Add(len(svc.servers))
+	for _, srv := range svc.servers {
+		go serve(srv, wg)
+	}
+
+	wg.Wait()
+
+	return nil
+}
+
+// serve starts and runs srv and writes all errors into its log.
+func serve(srv *http.Server, wg *sync.WaitGroup) {
+	addr := srv.Addr
+	defer log.OnPanic(addr)
+
+	var proto string
+	var l net.Listener
+	var err error
+	if srv.TLSConfig == nil {
+		proto = "http"
+		l, err = net.Listen("tcp", addr)
+	} else {
+		proto = "https"
+		l, err = tls.Listen("tcp", addr, srv.TLSConfig)
+	}
+	if err != nil {
+		srv.ErrorLog.Printf("starting srv %s: binding: %s", addr, err)
+	}
+
+	// Update the server's address in case the address had the port zero, which
+	// would mean that a random available port was automatically chosen.
+	srv.Addr = l.Addr().String()
+
+	log.Info("websvc: starting srv %s://%s", proto, srv.Addr)
+
+	l = &waitListener{
+		Listener:      l,
+		firstAcceptWG: wg,
+	}
+
+	err = srv.Serve(l)
+	if err != nil && !errors.Is(err, http.ErrServerClosed) {
+		srv.ErrorLog.Printf("starting srv %s: %s", addr, err)
+	}
+}
+
+// Shutdown implements the [agh.Service] interface for *Service.  svc may be
+// nil.
+func (svc *Service) Shutdown(ctx context.Context) (err error) {
+	if svc == nil {
+		return nil
+	}
+
+	var errs []error
+	for _, srv := range svc.servers {
+		serr := srv.Shutdown(ctx)
+		if serr != nil {
+			errs = append(errs, fmt.Errorf("shutting down srv %s: %w", srv.Addr, serr))
+		}
+	}
+
+	if len(errs) > 0 {
+		return errors.List("shutting down", errs...)
+	}
+
+	return nil
+}
+
+// Config returns the current configuration of the web service.  Config must not
+// be called simultaneously with Start.  If svc was initialized with ":0"
+// addresses, addrs will not return the actual bound ports until Start is
+// finished.
+func (svc *Service) Config() (c *Config) {
+	c = &Config{
+		ConfigManager: svc.confMgr,
+		TLS:           svc.tls,
+		// Leave Addresses and SecureAddresses empty and get the actual
+		// addresses that include the :0 ones later.
+		Start:      svc.start,
+		Timeout:    svc.timeout,
+		ForceHTTPS: svc.forceHTTPS,
+	}
+
+	c.Addresses, c.SecureAddresses = svc.addrs()
+
+	return c
+}

internal/next/websvc/websvc_internal_test.go

@@ -0,0 +1,6 @@
+package websvc
+
+import "time"
+
+// testTimeout is the common timeout for tests.
+const testTimeout = 1 * time.Second

internal/next/websvc/websvc_test.go

@@ -0,0 +1,187 @@
+package websvc_test
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
+	"github.com/AdguardTeam/golibs/testutil"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMain(m *testing.M) {
+	testutil.DiscardLogOutput(m)
+}
+
+// testTimeout is the common timeout for tests.
+const testTimeout = 1 * time.Second
+
+// testStart is the server start value for tests.
+var testStart = time.Date(2022, 1, 1, 0, 0, 0, 0, time.UTC)
+
+// type check
+var _ websvc.ConfigManager = (*configManager)(nil)
+
+// configManager is a [websvc.ConfigManager] for tests.
+type configManager struct {
+	onDNS func() (svc agh.ServiceWithConfig[*dnssvc.Config])
+	onWeb func() (svc agh.ServiceWithConfig[*websvc.Config])
+
+	onUpdateDNS func(ctx context.Context, c *dnssvc.Config) (err error)
+	onUpdateWeb func(ctx context.Context, c *websvc.Config) (err error)
+}
+
+// DNS implements the [websvc.ConfigManager] interface for *configManager.
+func (m *configManager) DNS() (svc agh.ServiceWithConfig[*dnssvc.Config]) {
+	return m.onDNS()
+}
+
+// Web implements the [websvc.ConfigManager] interface for *configManager.
+func (m *configManager) Web() (svc agh.ServiceWithConfig[*websvc.Config]) {
+	return m.onWeb()
+}
+
+// UpdateDNS implements the [websvc.ConfigManager] interface for *configManager.
+func (m *configManager) UpdateDNS(ctx context.Context, c *dnssvc.Config) (err error) {
+	return m.onUpdateDNS(ctx, c)
+}
+
+// UpdateWeb implements the [websvc.ConfigManager] interface for *configManager.
+func (m *configManager) UpdateWeb(ctx context.Context, c *websvc.Config) (err error) {
+	return m.onUpdateWeb(ctx, c)
+}
+
+// newConfigManager returns a *configManager all methods of which panic.
+func newConfigManager() (m *configManager) {
+	return &configManager{
+		onDNS: func() (svc agh.ServiceWithConfig[*dnssvc.Config]) { panic("not implemented") },
+		onWeb: func() (svc agh.ServiceWithConfig[*websvc.Config]) { panic("not implemented") },
+		onUpdateDNS: func(_ context.Context, _ *dnssvc.Config) (err error) {
+			panic("not implemented")
+		},
+		onUpdateWeb: func(_ context.Context, _ *websvc.Config) (err error) {
+			panic("not implemented")
+		},
+	}
+}
+
+// newTestServer creates and starts a new web service instance as well as its
+// sole address.  It also registers a cleanup procedure, which shuts the
+// instance down.
+//
+// TODO(a.garipov): Use svc or remove it.
+func newTestServer(
+	t testing.TB,
+	confMgr websvc.ConfigManager,
+) (svc *websvc.Service, addr netip.AddrPort) {
+	t.Helper()
+
+	c := &websvc.Config{
+		ConfigManager:   confMgr,
+		TLS:             nil,
+		Addresses:       []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:0")},
+		SecureAddresses: nil,
+		Timeout:         testTimeout,
+		Start:           testStart,
+		ForceHTTPS:      false,
+	}
+
+	svc = websvc.New(c)
+
+	err := svc.Start()
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+		t.Cleanup(cancel)
+
+		err = svc.Shutdown(ctx)
+		require.NoError(t, err)
+	})
+
+	c = svc.Config()
+	require.NotNil(t, c)
+	require.Len(t, c.Addresses, 1)
+
+	return svc, c.Addresses[0]
+}
+
+// jobj is a utility alias for JSON objects.
+type jobj map[string]any
+
+// httpGet is a helper that performs an HTTP GET request and returns the body of
+// the response as well as checks that the status code is correct.
+//
+// TODO(a.garipov): Add helpers for other methods.
+func httpGet(t testing.TB, u *url.URL, wantCode int) (body []byte) {
+	t.Helper()
+
+	req, err := http.NewRequest(http.MethodGet, u.String(), nil)
+	require.NoErrorf(t, err, "creating req")
+
+	httpCli := &http.Client{
+		Timeout: testTimeout,
+	}
+	resp, err := httpCli.Do(req)
+	require.NoErrorf(t, err, "performing req")
+	require.Equal(t, wantCode, resp.StatusCode)
+
+	testutil.CleanupAndRequireSuccess(t, resp.Body.Close)
+
+	body, err = io.ReadAll(resp.Body)
+	require.NoErrorf(t, err, "reading body")
+
+	return body
+}
+
+// httpPatch is a helper that performs an HTTP PATCH request with JSON-encoded
+// reqBody as the request body and returns the body of the response as well as
+// checks that the status code is correct.
+//
+// TODO(a.garipov): Add helpers for other methods.
+func httpPatch(t testing.TB, u *url.URL, reqBody any, wantCode int) (body []byte) {
+	t.Helper()
+
+	b, err := json.Marshal(reqBody)
+	require.NoErrorf(t, err, "marshaling reqBody")
+
+	req, err := http.NewRequest(http.MethodPatch, u.String(), bytes.NewReader(b))
+	require.NoErrorf(t, err, "creating req")
+
+	httpCli := &http.Client{
+		Timeout: testTimeout,
+	}
+	resp, err := httpCli.Do(req)
+	require.NoErrorf(t, err, "performing req")
+	require.Equal(t, wantCode, resp.StatusCode)
+
+	testutil.CleanupAndRequireSuccess(t, resp.Body.Close)
+
+	body, err = io.ReadAll(resp.Body)
+	require.NoErrorf(t, err, "reading body")
+
+	return body
+}
+
+func TestService_Start_getHealthCheck(t *testing.T) {
+	confMgr := newConfigManager()
+	_, addr := newTestServer(t, confMgr)
+	u := &url.URL{
+		Scheme: "http",
+		Host:   addr.String(),
+		Path:   websvc.PathHealthCheck,
+	}
+
+	body := httpGet(t, u, http.StatusOK)
+
+	assert.Equal(t, []byte("OK"), body)
+}

internal/stats/stats.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"net"
+	"net/netip"
 	"os"
 	"sync"
 	"sync/atomic"
@@ -64,7 +65,7 @@ type Interface interface {
 
 	// GetTopClientIP returns at most limit IP addresses corresponding to the
 	// clients with the most number of requests.
-	TopClientsIP(limit uint) []net.IP
+	TopClientsIP(limit uint) []netip.Addr
 
 	// WriteDiskConfig puts the Interface's configuration to the dc.
 	WriteDiskConfig(dc *DiskConfig)
@@ -107,8 +108,6 @@ type StatsCtx struct {
 	filename string
 }
 
-var _ Interface = &StatsCtx{}
-
 // New creates s from conf and properly initializes it.  Don't use s before
 // calling it's Start method.
 func New(conf Config) (s *StatsCtx, err error) {
@@ -178,6 +177,9 @@ func withRecovered(orig *error) {
 	*orig = errors.WithDeferred(*orig, err)
 }
 
+// type check
+var _ Interface = (*StatsCtx)(nil)
+
 // Start implements the Interface interface for *StatsCtx.
 func (s *StatsCtx) Start() {
 	s.initWeb()
@@ -250,8 +252,8 @@ func (s *StatsCtx) WriteDiskConfig(dc *DiskConfig) {
 	dc.Interval = atomic.LoadUint32(&s.limitHours) / 24
 }
 
-// TopClientsIP implements the Interface interface for *StatsCtx.
-func (s *StatsCtx) TopClientsIP(maxCount uint) (ips []net.IP) {
+// TopClientsIP implements the [Interface] interface for *StatsCtx.
+func (s *StatsCtx) TopClientsIP(maxCount uint) (ips []netip.Addr) {
 	limit := atomic.LoadUint32(&s.limitHours)
 	if limit == 0 {
 		return nil
@@ -271,10 +273,10 @@ func (s *StatsCtx) TopClientsIP(maxCount uint) (ips []net.IP) {
 	}
 
 	a := convertMapToSlice(m, int(maxCount))
-	ips = []net.IP{}
+	ips = []netip.Addr{}
 	for _, it := range a {
-		ip := net.ParseIP(it.Name)
-		if ip != nil {
+		ip, err := netip.ParseAddr(it.Name)
+		if err == nil {
 			ips = append(ips, ip)
 		}
 	}

internal/stats/stats_test.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/stats"
+	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/AdguardTeam/golibs/testutil"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -45,7 +46,7 @@ func assertSuccessAndUnmarshal(t *testing.T, to any, handler http.Handler, req *
 }
 
 func TestStats(t *testing.T) {
-	cliIP := net.IP{127, 0, 0, 1}
+	cliIP := netutil.IPv4Localhost()
 	cliIPStr := cliIP.String()
 
 	handlers := map[string]http.Handler{}
@@ -123,7 +124,7 @@ func TestStats(t *testing.T) {
 		topClients := s.TopClientsIP(2)
 		require.NotEmpty(t, topClients)
 
-		assert.True(t, cliIP.Equal(topClients[0]))
+		assert.Equal(t, cliIP, topClients[0])
 	})
 
 	t.Run("reset", func(t *testing.T) {

main.go

@@ -1,3 +1,6 @@
+//go:build !next
+// +build !next
+
 package main
 
 import (

main_next.go

@@ -0,0 +1,21 @@
+//go:build next
+// +build next
+
+package main
+
+import (
+	"embed"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/next/cmd"
+)
+
+// Embed the prebuilt client here since we strive to keep .go files inside the
+// internal directory and the embed package is unable to embed files located
+// outside of the same or underlying directory.
+
+//go:embed build2
+var clientBuildFS embed.FS
+
+func main() {
+	cmd.Main(clientBuildFS)
+}

scripts/make/go-build.sh

@@ -123,4 +123,14 @@ CGO_ENABLED="$cgo_enabled"
 GO111MODULE='on'
 export CGO_ENABLED GO111MODULE
 
-"$go" build --ldflags "$ldflags" "$race_flags" --trimpath "$o_flags" "$v_flags" "$x_flags"
+# Build the new binary if requested.
+if [ "${NEXTAPI:-0}" -eq '0' ]
+then
+	tags_flags='--tags='
+else
+	tags_flags='--tags=next'
+fi
+readonly tags_flags
+
+"$go" build --ldflags "$ldflags" "$race_flags" "$tags_flags" --trimpath "$o_flags" "$v_flags"\
+	"$x_flags"

scripts/make/go-lint.sh

@@ -136,6 +136,7 @@ underscores() {
 			-e '_freebsd.go'\
 			-e '_linux.go'\
 			-e '_little.go'\
+			-e '_next.go'\
 			-e '_openbsd.go'\
 			-e '_others.go'\
 			-e '_test.go'\
@@ -227,7 +228,7 @@ gocyclo --over 13 ./internal/dhcpd ./internal/filtering/ ./internal/home/
 # Apply stricter standards to new or somewhat refactored code.
 gocyclo --over 10 ./internal/aghio/ ./internal/aghnet/ ./internal/aghos/\
 	./internal/aghtest/ ./internal/dnsforward/ ./internal/stats/\
-	./internal/tools/ ./internal/updater/ ./internal/version/\
+	./internal/tools/ ./internal/updater/ ./internal/next/ ./internal/version/\
 	./scripts/vetted-filters/ ./main.go
 
 ineffassign ./...