websvc: imp restart

Updates #4970.

Squashed commit of the following:

commit 10365d9c8474e9d9735f581fb32b2892b2153cc4
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Fri Sep 30 14:23:06 2022 +0300

    all: imp docs, names

commit cff1103a0618a6430dc91e7e018febbf313c12ba
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Fri Sep 30 14:02:38 2022 +0300

    home: imp content-type check

CHANGELOG.md

@@ -15,6 +15,19 @@ and this project adheres to
 ## [v0.108.0] - TBA (APPROX.)
 -->
 
+### Security
+
+- As an additional CSRF protection measure, AdGuard Home now ensures that
+  requests that change its state but have no body (such as `POST
+  /control/stats_reset` requests) do not have a `Content-Type` header set on
+  them ([#4970]).
+
+### Fixed
+
+- `only application/json is allowed` errors in various APIs ([#4970]).
+
+[#4970]: https://github.com/AdguardTeam/AdGuardHome/issues/4970
+
 
 
 <!--
@@ -63,8 +76,8 @@ bodies are documented in `openapi/openapi.yaml` and `openapi/CHANGELOG.md`.
 
 #### Stricter Content-Type Checks (BREAKING API CHANGE)
 
-All JSON APIs now check if the request actually has the `application/json`
+All JSON APIs that expect a body now check if the request actually has
-content-type.
+`Content-Type` set to `application/json`.
 
 #### Other Security Changes
 

Makefile

@@ -34,7 +34,7 @@ YARN_INSTALL_FLAGS = $(YARN_FLAGS) --network-timeout 120000 --silent\
 	--ignore-engines --ignore-optional --ignore-platform\
 	--ignore-scripts
 
-V1API = 0
+NEXTAPI = 0
 
 # Macros for the build-release target.  If FRONTEND_PREBUILT is 0, the
 # default, the macro $(BUILD_RELEASE_DEPS_$(FRONTEND_PREBUILT)) expands
@@ -63,7 +63,7 @@ ENV = env\
 	PATH="$${PWD}/bin:$$( "$(GO.MACRO)" env GOPATH )/bin:$${PATH}"\
 	RACE='$(RACE)'\
 	SIGN='$(SIGN)'\
-	V1API='$(V1API)'\
+	NEXTAPI='$(NEXTAPI)'\
 	VERBOSE='$(VERBOSE)'\
 	VERSION='$(VERSION)'\
 

client/src/api/Api.js

@@ -10,11 +10,17 @@ class Api {
     async makeRequest(path, method = 'POST', config) {
         const url = `${this.baseUrl}/${path}`;
 
+        const axiosConfig = config || {};
+        if (method !== 'GET' && axiosConfig.data) {
+            axiosConfig.headers = axiosConfig.headers || {};
+            axiosConfig.headers['Content-Type'] = axiosConfig.headers['Content-Type'] || 'application/json';
+        }
+
         try {
             const response = await axios({
                 url,
                 method,
-                ...config,
+                ...axiosConfig,
             });
             return response.data;
         } catch (error) {
@@ -55,7 +61,6 @@ class Api {
         const { path, method } = this.GLOBAL_TEST_UPSTREAM_DNS;
         const config = {
             data: servers,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -64,7 +69,6 @@ class Api {
         const { path, method } = this.GLOBAL_VERSION;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -100,7 +104,6 @@ class Api {
         const { path, method } = this.FILTERING_REFRESH;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
 
         return this.makeRequest(path, method, parameters);
@@ -110,7 +113,6 @@ class Api {
         const { path, method } = this.FILTERING_ADD_FILTER;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
 
         return this.makeRequest(path, method, parameters);
@@ -120,7 +122,6 @@ class Api {
         const { path, method } = this.FILTERING_REMOVE_FILTER;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
 
         return this.makeRequest(path, method, parameters);
@@ -130,7 +131,6 @@ class Api {
         const { path, method } = this.FILTERING_SET_RULES;
         const parameters = {
             data: rules,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -139,7 +139,6 @@ class Api {
         const { path, method } = this.FILTERING_CONFIG;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -148,7 +147,6 @@ class Api {
         const { path, method } = this.FILTERING_SET_URL;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -239,7 +237,6 @@ class Api {
         const { path, method } = this.CHANGE_LANGUAGE;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -275,7 +272,6 @@ class Api {
         const { path, method } = this.DHCP_SET_CONFIG;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -284,7 +280,6 @@ class Api {
         const { path, method } = this.DHCP_FIND_ACTIVE;
         const parameters = {
             data: req,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -293,7 +288,6 @@ class Api {
         const { path, method } = this.DHCP_ADD_STATIC_LEASE;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -302,7 +296,6 @@ class Api {
         const { path, method } = this.DHCP_REMOVE_STATIC_LEASE;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -333,7 +326,6 @@ class Api {
         const { path, method } = this.INSTALL_CONFIGURE;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -342,7 +334,6 @@ class Api {
         const { path, method } = this.INSTALL_CHECK_CONFIG;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -363,7 +354,6 @@ class Api {
         const { path, method } = this.TLS_CONFIG;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -372,7 +362,6 @@ class Api {
         const { path, method } = this.TLS_VALIDATE;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -397,7 +386,6 @@ class Api {
         const { path, method } = this.ADD_CLIENT;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -406,7 +394,6 @@ class Api {
         const { path, method } = this.DELETE_CLIENT;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -415,7 +402,6 @@ class Api {
         const { path, method } = this.UPDATE_CLIENT;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -440,7 +426,6 @@ class Api {
         const { path, method } = this.ACCESS_SET;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -461,7 +446,6 @@ class Api {
         const { path, method } = this.REWRITE_ADD;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -470,7 +454,6 @@ class Api {
         const { path, method } = this.REWRITE_DELETE;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -496,7 +479,6 @@ class Api {
         const { path, method } = this.BLOCKED_SERVICES_SET;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -524,7 +506,6 @@ class Api {
         const { path, method } = this.STATS_CONFIG;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -560,7 +541,6 @@ class Api {
         const { path, method } = this.QUERY_LOG_CONFIG;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -577,7 +557,6 @@ class Api {
         const { path, method } = this.LOGIN;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -604,7 +583,6 @@ class Api {
         const { path, method } = this.SET_DNS_CONFIG;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }

internal/aghchan/aghchan.go

@@ -0,0 +1,33 @@
+// Package aghchan contains channel utilities.
+package aghchan
+
+import (
+	"fmt"
+	"time"
+)
+
+// Receive returns an error if it cannot receive a value form c before timeout
+// runs out.
+func Receive[T any](c <-chan T, timeout time.Duration) (v T, ok bool, err error) {
+	var zero T
+	timeoutCh := time.After(timeout)
+	select {
+	case <-timeoutCh:
+		// TODO(a.garipov): Consider implementing [errors.Aser] for
+		// os.ErrTimeout.
+		return zero, false, fmt.Errorf("did not receive after %s", timeout)
+	case v, ok = <-c:
+		return v, ok, nil
+	}
+}
+
+// MustReceive panics if it cannot receive a value form c before timeout runs
+// out.
+func MustReceive[T any](c <-chan T, timeout time.Duration) (v T, ok bool) {
+	v, ok, err := Receive(c, timeout)
+	if err != nil {
+		panic(err)
+	}
+
+	return v, ok
+}

internal/aghhttp/aghhttp.go

@@ -33,7 +33,7 @@ func OK(w http.ResponseWriter) {
 // Error writes formatted message to w and also logs it.
 func Error(r *http.Request, w http.ResponseWriter, code int, format string, args ...any) {
 	text := fmt.Sprintf(format, args...)
-	log.Error("%s %s: %s", r.Method, r.URL, text)
+	log.Error("%s %s %s: %s", r.Method, r.Host, r.URL, text)
 	http.Error(w, text, code)
 }
 

internal/aghhttp/header.go

@@ -8,8 +8,8 @@ package aghhttp
 const (
 	HdrNameAcceptEncoding           = "Accept-Encoding"
 	HdrNameAccessControlAllowOrigin = "Access-Control-Allow-Origin"
-	HdrNameContentType              = "Content-Type"
 	HdrNameContentEncoding          = "Content-Encoding"
+	HdrNameContentType              = "Content-Type"
 	HdrNameServer                   = "Server"
 	HdrNameTrailer                  = "Trailer"
 	HdrNameUserAgent                = "User-Agent"

internal/aghnet/hostscontainer_test.go

@@ -10,9 +10,9 @@ import (
 	"testing/fstest"
 	"time"
 
+	"github.com/AdguardTeam/AdGuardHome/internal/aghchan"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
 	"github.com/AdguardTeam/golibs/errors"
-	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/AdguardTeam/golibs/stringutil"
 	"github.com/AdguardTeam/golibs/testutil"
 	"github.com/AdguardTeam/urlfilter"
@@ -163,15 +163,9 @@ func TestHostsContainer_refresh(t *testing.T) {
 	checkRefresh := func(t *testing.T, want *HostsRecord) {
 		t.Helper()
 
-		var ok bool
+		upd, ok := aghchan.MustReceive(hc.Upd(), 1*time.Second)
-		var upd *netutil.IPMap
-		select {
-		case upd, ok = <-hc.Upd():
 		require.True(t, ok)
 		require.NotNil(t, upd)
-		case <-time.After(1 * time.Second):
-			t.Fatal("did not receive after 1s")
-		}
 
 		assert.Equal(t, 1, upd.Len())
 

internal/aghtest/interface.go

@@ -1,6 +1,7 @@
 package aghtest
 
 import (
+	"context"
 	"io/fs"
 	"net"
 
@@ -15,6 +16,8 @@ import (
 
 // Standard Library
 
+// Package fs
+
 // type check
 var _ fs.FS = &FS{}
 
@@ -58,6 +61,8 @@ func (fsys *StatFS) Stat(name string) (fs.FileInfo, error) {
 	return fsys.OnStat(name)
 }
 
+// Package net
+
 // type check
 var _ net.Listener = (*Listener)(nil)
 
@@ -83,32 +88,10 @@ func (l *Listener) Close() (err error) {
 	return l.OnClose()
 }
 
-// Module dnsproxy
-
-// type check
-var _ upstream.Upstream = (*UpstreamMock)(nil)
-
-// UpstreamMock is a mock [upstream.Upstream] implementation for tests.
-//
-// TODO(a.garipov): Replace with all uses of Upstream with UpstreamMock and
-// rename it to just Upstream.
-type UpstreamMock struct {
-	OnAddress  func() (addr string)
-	OnExchange func(req *dns.Msg) (resp *dns.Msg, err error)
-}
-
-// Address implements the [upstream.Upstream] interface for *UpstreamMock.
-func (u *UpstreamMock) Address() (addr string) {
-	return u.OnAddress()
-}
-
-// Exchange implements the [upstream.Upstream] interface for *UpstreamMock.
-func (u *UpstreamMock) Exchange(req *dns.Msg) (resp *dns.Msg, err error) {
-	return u.OnExchange(req)
-}
-
 // Module AdGuardHome
 
+// Package aghos
+
 // type check
 var _ aghos.FSWatcher = (*FSWatcher)(nil)
 
@@ -133,3 +116,57 @@ func (w *FSWatcher) Add(name string) (err error) {
 func (w *FSWatcher) Close() (err error) {
 	return w.OnClose()
 }
+
+// Package websvc
+
+// ServiceWithConfig is a mock [websvc.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 [websvc.ServiceWithConfig] interface for
+// *ServiceWithConfig.
+func (s *ServiceWithConfig[_]) Start() (err error) {
+	return s.OnStart()
+}
+
+// Shutdown implements the [websvc.ServiceWithConfig] interface for
+// *ServiceWithConfig.
+func (s *ServiceWithConfig[_]) Shutdown(ctx context.Context) (err error) {
+	return s.OnShutdown(ctx)
+}
+
+// Config implements the [websvc.ServiceWithConfig] interface for
+// *ServiceWithConfig.
+func (s *ServiceWithConfig[ConfigType]) Config() (c ConfigType) {
+	return s.OnConfig()
+}
+
+// Module dnsproxy
+
+// Package upstream
+
+// type check
+var _ upstream.Upstream = (*UpstreamMock)(nil)
+
+// UpstreamMock is a mock [upstream.Upstream] implementation for tests.
+//
+// TODO(a.garipov): Replace with all uses of Upstream with UpstreamMock and
+// rename it to just Upstream.
+type UpstreamMock struct {
+	OnAddress  func() (addr string)
+	OnExchange func(req *dns.Msg) (resp *dns.Msg, err error)
+}
+
+// Address implements the [upstream.Upstream] interface for *UpstreamMock.
+func (u *UpstreamMock) Address() (addr string) {
+	return u.OnAddress()
+}
+
+// Exchange implements the [upstream.Upstream] interface for *UpstreamMock.
+func (u *UpstreamMock) Exchange(req *dns.Msg) (resp *dns.Msg, err error) {
+	return u.OnExchange(req)
+}

internal/aghtest/interface_test.go

@@ -1,9 +1,9 @@
 package aghtest_test
 
 import (
-	"github.com/AdguardTeam/AdGuardHome/internal/aghos"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
 )
 
 // type check
-var _ aghos.FSWatcher = (*aghtest.FSWatcher)(nil)
+var _ websvc.ServiceWithConfig[struct{}] = (*aghtest.ServiceWithConfig[struct{}])(nil)

internal/home/control.go

@@ -8,6 +8,7 @@ import (
 	"net/url"
 	"runtime"
 	"strings"
+	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
@@ -97,6 +98,8 @@ func collectDNSAddresses() (addrs []string, err error) {
 
 // statusResponse is a response for /control/status endpoint.
 type statusResponse struct {
+	Version             string   `json:"version"`
+	Language            string   `json:"language"`
 	DNSAddrs            []string `json:"dns_addresses"`
 	DNSPort             int      `json:"dns_port"`
 	HTTPPort            int      `json:"http_port"`
@@ -105,8 +108,6 @@ type statusResponse struct {
 	// openapi.yaml declares.
 	IsDHCPAvailable bool `json:"dhcp_available"`
 	IsRunning       bool `json:"running"`
-	Version         string `json:"version"`
-	Language        string `json:"language"`
 }
 
 func handleStatus(w http.ResponseWriter, r *http.Request) {
@@ -125,12 +126,12 @@ func handleStatus(w http.ResponseWriter, r *http.Request) {
 		defer config.RUnlock()
 
 		resp = statusResponse{
+			Version:   version.Version(),
 			DNSAddrs:  dnsAddrs,
 			DNSPort:   config.DNS.Port,
 			HTTPPort:  config.BindPort,
-			IsRunning: isRunning(),
-			Version:   version.Version(),
 			Language:  config.Language,
+			IsRunning: isRunning(),
 		}
 	}()
 
@@ -196,29 +197,26 @@ func httpRegister(method, url string, handler http.HandlerFunc) {
 	Context.mux.Handle(url, postInstallHandler(optionalAuthHandler(gziphandler.GzipHandler(ensureHandler(method, handler)))))
 }
 
-// ----------------------------------
+// ensure returns a wrapped handler that makes sure that the request has the
-// helper functions for HTTP handlers
+// correct method as well as additional method and header checks.
-// ----------------------------------
+func ensure(
-func ensure(method string, handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) {
+	method string,
+	handler func(http.ResponseWriter, *http.Request),
+) (wrapped func(http.ResponseWriter, *http.Request)) {
 	return func(w http.ResponseWriter, r *http.Request) {
-		log.Debug("%s %v", r.Method, r.URL)
+		start := time.Now()
+		m, u := r.Method, r.URL
+		log.Debug("started %s %s %s", m, r.Host, u)
+		defer func() { log.Debug("finished %s %s %s in %s", m, r.Host, u, time.Since(start)) }()
 
-		if r.Method != method {
+		if m != method {
-			aghhttp.Error(r, w, http.StatusMethodNotAllowed, "only %s is allowed", method)
+			aghhttp.Error(r, w, http.StatusMethodNotAllowed, "only method %s is allowed", method)
 
 			return
 		}
 
-		if method == http.MethodPost || method == http.MethodPut || method == http.MethodDelete {
+		if modifiesData(m) {
-			if r.Header.Get(aghhttp.HdrNameContentType) != aghhttp.HdrValApplicationJSON {
+			if !ensureContentType(w, r) {
-				aghhttp.Error(
-					r,
-					w,
-					http.StatusUnsupportedMediaType,
-					"only %s is allowed",
-					aghhttp.HdrValApplicationJSON,
-				)
-
 				return
 			}
 
@@ -230,6 +228,42 @@ func ensure(method string, handler func(http.ResponseWriter, *http.Request)) fun
 	}
 }
 
+// modifiesData returns true if m is an HTTP method that can modify data.
+func modifiesData(m string) (ok bool) {
+	return m == http.MethodPost || m == http.MethodPut || m == http.MethodDelete
+}
+
+// ensureContentType makes sure that the content type of a data-modifying
+// request is set correctly.  If it is not, ensureContentType writes a response
+// to w, and ok is false.
+func ensureContentType(w http.ResponseWriter, r *http.Request) (ok bool) {
+	const statusUnsup = http.StatusUnsupportedMediaType
+
+	cType := r.Header.Get(aghhttp.HdrNameContentType)
+	if r.ContentLength == 0 {
+		if cType == "" {
+			return true
+		}
+
+		// Assume that browsers always send a content type when submitting HTML
+		// forms and require no content type for requests with no body to make
+		// sure that the request comes from JavaScript.
+		aghhttp.Error(r, w, statusUnsup, "empty body with content-type %q not allowed", cType)
+
+		return false
+
+	}
+
+	const wantCType = aghhttp.HdrValApplicationJSON
+	if cType == wantCType {
+		return true
+	}
+
+	aghhttp.Error(r, w, statusUnsup, "only content-type %s is allowed", wantCType)
+
+	return false
+}
+
 func ensurePOST(handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) {
 	return ensure(http.MethodPost, handler)
 }

internal/next/cmd/cmd.go

@@ -11,29 +11,32 @@ import (
 	"net/netip"
 	"time"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/websvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
 	"github.com/AdguardTeam/golibs/log"
 )
 
 // Main is the entry point of application.
 func Main(clientBuildFS fs.FS) {
-	// # Initial Configuration
+	// Initial Configuration
 
 	start := time.Now()
 	rand.Seed(start.UnixNano())
 
 	// TODO(a.garipov): Set up logging.
 
-	// # Web Service
+	// Web Service
 
 	// TODO(a.garipov): Use in the Web service.
 	_ = clientBuildFS
 
 	// TODO(a.garipov): Make configurable.
 	web := websvc.New(&websvc.Config{
+		// TODO(a.garipov): Use an actual implementation.
+		ConfigManager: nil,
 		Addresses:     []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:3001")},
 		Start:         start,
 		Timeout:       60 * time.Second,
+		ForceHTTPS:    false,
 	})
 
 	err := web.Start()

internal/next/cmd/signal.go

@@ -4,7 +4,7 @@ import (
 	"os"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghos"
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/agh"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
 	"github.com/AdguardTeam/golibs/log"
 )
 

internal/next/dnssvc/dnssvc.go

@@ -9,9 +9,10 @@ import (
 	"fmt"
 	"net"
 	"net/netip"
+	"sync/atomic"
 	"time"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/agh"
+	"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"
@@ -47,6 +48,14 @@ type Config struct {
 // 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
@@ -160,6 +169,17 @@ func (svc *Service) Start() (err error) {
 		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()
 }
 
@@ -173,14 +193,28 @@ func (svc *Service) Shutdown(ctx context.Context) (err error) {
 	return svc.proxy.Stop()
 }
 
-// Config returns the current configuration of the web service.
+// 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))
+		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,

internal/next/dnssvc/dnssvc_test.go

@@ -7,7 +7,7 @@ import (
 	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/dnssvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
 	"github.com/AdguardTeam/dnsproxy/upstream"
 	"github.com/miekg/dns"
 	"github.com/stretchr/testify/assert"

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 +1,68 @@
+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/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 websvc.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 +1,109 @@
+package websvc
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/netip"
+	"time"
+
+	"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 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 +1,62 @@
+package websvc_test
+
+import (
+	"context"
+	"crypto/tls"
+	"encoding/json"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"testing"
+	"time"
+
+	"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 websvc.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/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 +1,74 @@
+package websvc_test
+
+import (
+	"crypto/tls"
+	"encoding/json"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"testing"
+	"time"
+
+	"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 websvc.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 websvc.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

@@ -16,20 +16,20 @@ type RespGetV1SystemInfo struct {
 	Channel    string   `json:"channel"`
 	OS         string   `json:"os"`
 	NewVersion string   `json:"new_version,omitempty"`
-	Start      jsonTime `json:"start"`
+	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) {
-	writeJSONResponse(w, r, &RespGetV1SystemInfo{
+	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),
+		Start:      JSONTime(svc.start),
 		Version:    version.Version(),
 	})
 }

internal/next/websvc/system_test.go

@@ -8,16 +8,17 @@ import (
 	"testing"
 	"time"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/websvc"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
 func TestService_handleGetV1SystemInfo(t *testing.T) {
-	_, addr := newTestServer(t)
+	confMgr := newConfigManager()
+	_, addr := newTestServer(t, confMgr)
 	u := &url.URL{
 		Scheme: "http",
-		Host:   addr,
+		Host:   addr.String(),
 		Path:   websvc.PathV1SystemInfo,
 	}
 

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

@@ -1,4 +1,7 @@
-// Package websvc contains the AdGuard Home web service.
+// 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
@@ -14,18 +17,46 @@ import (
 	"sync"
 	"time"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/agh"
+	"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"
 )
 
+// ServiceWithConfig is an extension of the [agh.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 {
+	agh.Service
+
+	Config() (c ConfigType)
+}
+
+// ConfigManager is the configuration manager interface.
+type ConfigManager interface {
+	DNS() (svc ServiceWithConfig[*dnssvc.Config])
+	Web() (svc 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
 
@@ -33,40 +64,48 @@ type Config struct {
 	// SecureAddresses is not empty, TLS must not be nil.
 	SecureAddresses []netip.AddrPort
 
-	// Start is the time of start of AdGuard Home.
-	Start time.Time
-
 	// 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
-	servers []*http.Server
 	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.
+// *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: http: "+addr, log.ERROR)
+		errLog := log.StdLog("websvc: plain http: "+addr, log.ERROR)
 		svc.servers = append(svc.servers, &http.Server{
 			Addr:              addr,
 			Handler:           mux,
@@ -111,6 +150,21 @@ func newMux(svc *Service) (mux *httptreemux.ContextMux) {
 		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,
@@ -119,29 +173,41 @@ func newMux(svc *Service) (mux *httptreemux.ContextMux) {
 	}}
 
 	for _, r := range routes {
-		var h http.HandlerFunc
 		if r.isJSON {
-			// TODO(a.garipov): Consider using httptreemux's MiddlewareFunc.
+			mux.Handle(r.method, r.path, jsonMw(r.handler))
-			h = jsonMw(r.handler)
 		} else {
-			h = r.handler
+			mux.Handle(r.method, r.path, r.handler)
 		}
-
-		mux.Handle(r.method, r.path, h)
 	}
 
 	return mux
 }
 
-// Addrs returns all addresses on which this server serves the HTTP API.  Addrs
+// addrs returns all addresses on which this server serves the HTTP API.  addrs
-// must not be called until Start returns.
+// must not be called simultaneously with Start.  If svc was initialized with
-func (svc *Service) Addrs() (addrs []string) {
+// ":0" addresses, addrs will not return the actual bound ports until Start is
-	addrs = make([]string, 0, len(svc.servers))
+// finished.
+func (svc *Service) addrs() (addrs, secureAddrs []netip.AddrPort) {
 	for _, srv := range svc.servers {
-		addrs = append(addrs, srv.Addr)
+		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))
 		}
 
-	return addrs
+		// 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.
@@ -149,9 +215,6 @@ func (svc *Service) handleGetHealthCheck(w http.ResponseWriter, _ *http.Request)
 	_, _ = io.WriteString(w, "OK")
 }
 
-// unit is a convenient alias for struct{}.
-type unit = struct{}
-
 // type check
 var _ agh.Service = (*Service)(nil)
 
@@ -163,11 +226,9 @@ func (svc *Service) Start() (err error) {
 		return nil
 	}
 
-	srvs := svc.servers
-
 	wg := &sync.WaitGroup{}
-	wg.Add(len(srvs))
+	wg.Add(len(svc.servers))
-	for _, srv := range srvs {
+	for _, srv := range svc.servers {
 		go serve(srv, wg)
 	}
 
@@ -181,11 +242,14 @@ 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 {
@@ -196,8 +260,12 @@ func serve(srv *http.Server, wg *sync.WaitGroup) {
 	// would mean that a random available port was automatically chosen.
 	srv.Addr = l.Addr().String()
 
-	log.Info("websvc: starting srv http://%s", srv.Addr)
+	log.Info("websvc: starting srv %s://%s", proto, srv.Addr)
-	wg.Done()
+
+	l = &waitListener{
+		Listener:      l,
+		firstAcceptWG: wg,
+	}
 
 	err = srv.Serve(l)
 	if err != nil && !errors.Is(err, http.ErrServerClosed) {
@@ -221,8 +289,28 @@ func (svc *Service) Shutdown(ctx context.Context) (err error) {
 	}
 
 	if len(errs) > 0 {
-		return errors.List("shutting down")
+		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/aghtest"
+	"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) {
+	aghtest.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 websvc.ServiceWithConfig[*dnssvc.Config])
+	onWeb func() (svc websvc.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 websvc.ServiceWithConfig[*dnssvc.Config]) {
+	return m.onDNS()
+}
+
+// Web implements the [websvc.ConfigManager] interface for *configManager.
+func (m *configManager) Web() (svc websvc.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 websvc.ServiceWithConfig[*dnssvc.Config]) { panic("not implemented") },
+		onWeb: func() (svc websvc.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/v1/websvc/json.go

@@ -1,61 +0,0 @@
-package websvc
-
-import (
-	"encoding/json"
-	"fmt"
-	"io"
-	"net/http"
-	"strconv"
-	"time"
-
-	"github.com/AdguardTeam/golibs/log"
-)
-
-// JSON Utilities
-
-// 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{}
-
-// nsecPerMsec is the number of nanoseconds in a millisecond.
-const nsecPerMsec = float64(time.Millisecond / time.Nanosecond)
-
-// 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', 3, 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
-}
-
-// writeJSONResponse encodes v into w and logs any errors it encounters.  r is
-// used to get additional information from the request.
-func writeJSONResponse(w io.Writer, r *http.Request, v any) {
-	err := json.NewEncoder(w).Encode(v)
-	if err != nil {
-		log.Error("websvc: writing resp to %s %s: %s", r.Method, r.URL.Path, err)
-	}
-}

internal/v1/websvc/path.go

@@ -1,8 +0,0 @@
-package websvc
-
-// Path constants
-const (
-	PathHealthCheck = "/health-check"
-
-	PathV1SystemInfo = "/api/v1/system/info"
-)

internal/v1/websvc/websvc_test.go

@@ -1,93 +0,0 @@
-package websvc_test
-
-import (
-	"context"
-	"io"
-	"net/http"
-	"net/netip"
-	"net/url"
-	"testing"
-	"time"
-
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/websvc"
-	"github.com/AdguardTeam/golibs/testutil"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-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)
-
-// 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) (svc *websvc.Service, addr string) {
-	t.Helper()
-
-	c := &websvc.Config{
-		TLS:             nil,
-		Addresses:       []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:0")},
-		SecureAddresses: nil,
-		Timeout:         testTimeout,
-		Start:           testStart,
-	}
-
-	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)
-	})
-
-	addrs := svc.Addrs()
-	require.Len(t, addrs, 1)
-
-	return svc, addrs[0]
-}
-
-// 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
-}
-
-func TestService_Start_getHealthCheck(t *testing.T) {
-	_, addr := newTestServer(t)
-	u := &url.URL{
-		Scheme: "http",
-		Host:   addr,
-		Path:   websvc.PathHealthCheck,
-	}
-
-	body := httpGet(t, u, http.StatusOK)
-
-	assert.Equal(t, []byte("OK"), body)
-}

internal/version/version.go

@@ -63,14 +63,6 @@ func Version() (v string) {
 	return version
 }
 
-// Constants defining the format of module information string.
-const (
-	modInfoAtSep    = "@"
-	modInfoDevSep   = " "
-	modInfoSumLeft  = " (sum: "
-	modInfoSumRight = ")"
-)
-
 // fmtModule returns formatted information about module.  The result looks like:
 //
 //	github.com/Username/module@v1.2.3 (sum: someHASHSUM=)
@@ -87,14 +79,16 @@ func fmtModule(m *debug.Module) (formatted string) {
 
 	stringutil.WriteToBuilder(b, m.Path)
 	if ver := m.Version; ver != "" {
-		sep := modInfoAtSep
+		sep := "@"
 		if ver == "(devel)" {
-			sep = modInfoDevSep
+			sep = " "
 		}
+
 		stringutil.WriteToBuilder(b, sep, ver)
 	}
+
 	if sum := m.Sum; sum != "" {
-		stringutil.WriteToBuilder(b, modInfoSumLeft, sum, modInfoSumRight)
+		stringutil.WriteToBuilder(b, "(sum: ", sum, ")")
 	}
 
 	return b.String()

main.go

@@ -1,5 +1,5 @@
-//go:build !v1
+//go:build !next
-// +build !v1
+// +build !next
 
 package main
 

main_next.go

@@ -1,12 +1,12 @@
-//go:build v1
+//go:build next
-// +build v1
+// +build next
 
 package main
 
 import (
 	"embed"
 
-	"github.com/AdguardTeam/AdGuardHome/internal/v1/cmd"
+	"github.com/AdguardTeam/AdGuardHome/internal/next/cmd"
 )
 
 // Embed the prebuilt client here since we strive to keep .go files inside the

openapi/CHANGELOG.md

@@ -6,6 +6,28 @@
 
 
 
+## v0.107.15: `POST` Requests Without Bodies
+
+As an additional CSRF protection measure, AdGuard Home now ensures that requests
+that change its state but have no body do not have a `Content-Type` header set
+on them.
+
+This concerns the following APIs:
+
+* `POST /control/dhcp/reset_leases`;
+* `POST /control/dhcp/reset`;
+* `POST /control/parental/disable`;
+* `POST /control/parental/enable`;
+* `POST /control/querylog_clear`;
+* `POST /control/safebrowsing/disable`;
+* `POST /control/safebrowsing/enable`;
+* `POST /control/safesearch/disable`;
+* `POST /control/safesearch/enable`;
+* `POST /control/stats_reset`;
+* `POST /control/update`.
+
+
+
 ## v0.107.14: BREAKING API CHANGES
 
 A Cross-Site Request Forgery (CSRF) vulnerability has been discovered.  We have
@@ -13,6 +35,9 @@ implemented several measures to prevent such vulnerabilities in the future, but
 some of these measures break backwards compatibility for the sake of better
 protection.
 
+All JSON APIs that expect a body now check if the request actually has
+`Content-Type` set to `application/json`.
+
 All new formats for the request and response bodies are documented in
 `openapi.yaml`.
 

openapi/openapi.yaml

@@ -601,11 +601,10 @@
       'summary': 'Set user-defined filter rules'
       'requestBody':
         'content':
-          'text/plain':
+          'application/json':
             'schema':
-              'type': 'string'
+              '$ref': '#/components/schemas/SetRulesRequest'
-              'example': '@@||yandex.ru^|'
+        'description': 'Custom filtering rules.'
-        'description': 'All filtering rules, one line per rule'
       'responses':
         '200':
           'description': 'OK.'
@@ -1538,6 +1537,19 @@
       'properties':
         'updated':
           'type': 'integer'
+    'SetRulesRequest':
+      'description': 'Custom filtering rules setting request.'
+      'example':
+        'rules':
+        - '||example.com^'
+        - '# comment'
+        - '@@||www.example.com^'
+      'properties':
+        'rules':
+          'items':
+            'type': 'string'
+          'type': 'array'
+      'type': 'object'
     'GetVersionRequest':
       'type': 'object'
       'description': '/version.json request data'

openapi/v1.yaml

@@ -2289,7 +2289,7 @@
           'upstream_servers':
           - '1.1.1.1'
           - '8.8.8.8'
-          'upstream_timeout': '1s'
+          'upstream_timeout': 1000
         'required':
         - 'addresses'
         - 'blocking_mode'
@@ -2397,8 +2397,9 @@
           'type': 'array'
         'upstream_timeout':
           'description': >
-            Upstream request timeout, as a human readable duration.
+            Upstream request timeout, in milliseconds.
-          'type': 'string'
+          'format': 'double'
+          'type': 'number'
       'type': 'object'
 
     'DnsType':
@@ -3505,14 +3506,16 @@
           'addresses':
           - '127.0.0.1:80'
           - '192.168.1.1:80'
+          'force_https': true
           'secure_addresses':
           - '127.0.0.1:443'
           - '192.168.1.1:443'
-          'force_https': true
+          'timeout': 10000
         'required':
         - 'addresses'
-        - 'secure_addresses'
         - 'force_https'
+        - 'secure_addresses'
+        - 'timeout'
 
     'HttpSettingsPatch':
       'description': >
@@ -3539,6 +3542,11 @@
           'items':
             'type': 'string'
           'type': 'array'
+        'timeout':
+          'description': >
+            HTTP request timeout, in milliseconds.
+          'format': 'double'
+          'type': 'number'
       'type': 'object'
 
     'InternalServerErrorResp':

scripts/make/go-lint.sh

@@ -136,11 +136,11 @@ underscores() {
 			-e '_freebsd.go'\
 			-e '_linux.go'\
 			-e '_little.go'\
+			-e '_next.go'\
 			-e '_openbsd.go'\
 			-e '_others.go'\
 			-e '_test.go'\
 			-e '_unix.go'\
-			-e '_v1.go'\
 			-e '_windows.go' \
 			-v\
 			| sed -e 's/./\t\0/'
@@ -229,7 +229,7 @@ gocyclo --over 13 ./internal/filtering/
 # 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/v1/ ./internal/version/\
+	./internal/tools/ ./internal/updater/ ./internal/next/ ./internal/version/\
 	./main.go
 
 ineffassign ./...