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

@@ -12,11 +12,75 @@ and this project adheres to
 ## [Unreleased]
 
 <!--
-## [v0.108.0] - 2022-12-01 (APPROX.)
+## [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
+
+
+
+<!--
+## [v0.107.15] - 2022-10-26 (APPROX.)
+
+See also the [v0.107.15 GitHub milestone][ms-v0.107.15].
+
+[ms-v0.107.15]:   https://github.com/AdguardTeam/AdGuardHome/milestone/51?closed=1
+-->
+
+
+
+## [v0.107.14] - 2022-09-29
+
+See also the [v0.107.14 GitHub milestone][ms-v0.107.14].
+
+### Security
+
+A Cross-Site Request Forgery (CSRF) vulnerability has been discovered.  The CVE
+number is to be assigned.  We thank Daniel Elkabes from Mend.io for reporting
+this vulnerability to us.
+
+#### `SameSite` Policy
+
+The `SameSite` policy on the AdGuard Home session cookies is now set to `Lax`.
+Which means that the only cross-site HTTP request for which the browser is
+allowed to send the session cookie is navigating to the AdGuard Home domain.
+
+**Users are strongly advised to log out, clear browser cache, and log in again
+after updating.**
+
+#### Removal Of Plain-Text APIs (BREAKING API CHANGE)
+
+We have implemented several measures to prevent such vulnerabilities in the
+future, but some of these measures break backwards compatibility for the sake of
+better protection.
+
+The following APIs, which previously accepted or returned `text/plain` data,
+now accept or return data as JSON.  All new formats for the request and response
+bodies are documented in `openapi/openapi.yaml` and `openapi/CHANGELOG.md`.
+
+- `GET  /control/i18n/current_language`;
+- `POST /control/dhcp/find_active_dhcp`;
+- `POST /control/filtering/set_rules`;
+- `POST /control/i18n/change_language`.
+
+#### Stricter Content-Type Checks (BREAKING API CHANGE)
+
+All JSON APIs that expect a body now check if the request actually has
+`Content-Type` set to `application/json`.
+
+#### Other Security Changes
+
 - Weaker cipher suites that use the CBC (cipher block chaining) mode of
   operation have been disabled ([#2993]).
 
@@ -33,16 +97,7 @@ and this project adheres to
 [#4927]: https://github.com/AdguardTeam/AdGuardHome/issues/4927
 [#4930]: https://github.com/AdguardTeam/AdGuardHome/issues/4930
 
-
-
-
-<!--
-## [v0.107.14] - 2022-10-05 (APPROX.)
-
-See also the [v0.107.14 GitHub milestone][ms-v0.107.14].
-
 [ms-v0.107.14]:   https://github.com/AdguardTeam/AdGuardHome/milestone/50?closed=1
--->
 
 
 
@@ -1241,11 +1296,12 @@ See also the [v0.104.2 GitHub milestone][ms-v0.104.2].
 
 
 <!--
-[Unreleased]: https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.14...HEAD
+[Unreleased]: https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.15...HEAD
-[v0.107.14]:  https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.13...v0.107.14
+[v0.107.15]:  https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.14...v0.107.15
 -->
 
-[Unreleased]: https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.13...HEAD
+[Unreleased]: https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.14...HEAD
+[v0.107.14]:  https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.13...v0.107.14
 [v0.107.13]:  https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.12...v0.107.13
 [v0.107.12]:  https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.11...v0.107.12
 [v0.107.11]:  https://github.com/AdguardTeam/AdGuardHome/compare/v0.107.10...v0.107.11

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)'\
 

SECURITY.md

@@ -0,0 +1,18 @@
+ #  Security Policy
+
+## Reporting a Vulnerability
+
+Please send your vulnerability reports to <security@adguard.com>.  To make sure
+that your report reaches us, please:
+
+1.  Include the words “AdGuard Home” and “vulnerability” to the subject line as
+    well as a short description of the vulnerability.  For example:
+
+     >  AdGuard Home API vulnerability: possible XSS attack
+
+2.  Make sure that the message body contains a clear description of the
+    vulnerability.
+
+If you have not received a reply to your email within 7 days, please make sure
+to follow up with us again at <security@adguard.com>.  Once again, make sure
+that the word “vulnerability” is in the subject line.

client/src/__locales/be.json

@@ -635,5 +635,6 @@
     "parental_control": "Бацькоўскі кантроль",
     "safe_browsing": "Бяспечны інтэрнэт",
     "served_from_cache": "{{value}} <i>(атрымана з кэша)</i>",
-    "form_error_password_length": "Пароль павінен быць не менш за {{value}} сімвалаў"
+    "form_error_password_length": "Пароль павінен быць не менш за {{value}} сімвалаў",
+    "anonymizer_notification": "<0>Заўвага:</0> Ананімізацыя IP уключана. Вы можаце адключыць яго ў <1>Агульных наладах</1> ."
 }

client/src/__locales/cs.json

@@ -635,5 +635,6 @@
     "parental_control": "Rodičovská ochrana",
     "safe_browsing": "Bezpečné prohlížení",
     "served_from_cache": "{{value}} <i>(převzato z mezipaměti)</i>",
-    "form_error_password_length": "Heslo musí být alespoň {{value}} znaků dlouhé"
+    "form_error_password_length": "Heslo musí být alespoň {{value}} znaků dlouhé",
+    "anonymizer_notification": "<0>Poznámka:</0> Anonymizace IP je zapnuta. Můžete ji vypnout v <1>Obecných nastaveních</1>."
 }

client/src/__locales/da.json

@@ -635,5 +635,6 @@
     "parental_control": "Forældrekontrol",
     "safe_browsing": "Sikker Browsing",
     "served_from_cache": "{{value}} <i>(leveret fra cache)</i>",
-    "form_error_password_length": "Adgangskoden skal udgøre mindst {{value}} tegn."
+    "form_error_password_length": "Adgangskoden skal udgøre mindst {{value}} tegn.",
+    "anonymizer_notification": "<0>Bemærk:</0> IP-anonymisering er aktiveret. Det kan deaktiveres via <1>Generelle indstillinger</1>."
 }

client/src/__locales/de.json

@@ -635,5 +635,6 @@
     "parental_control": "Kindersicherung",
     "safe_browsing": "Internetsicherheit",
     "served_from_cache": "{{value}} <i>(aus dem Cache abgerufen)</i>",
-    "form_error_password_length": "Das Passwort muss mindestens {{value}} Zeichen enthalten"
+    "form_error_password_length": "Das Passwort muss mindestens {{value}} Zeichen enthalten",
+    "anonymizer_notification": "<0>Hinweis:</0> Die IP-Anonymisierung ist aktiviert. Sie können sie in den <1>Allgemeinen Einstellungen</1> deaktivieren."
 }

client/src/__locales/es.json

@@ -635,5 +635,6 @@
     "parental_control": "Control parental",
     "safe_browsing": "Navegación segura",
     "served_from_cache": "{{value}} <i>(servido desde la caché)</i>",
-    "form_error_password_length": "La contraseña debe tener al menos {{value}} caracteres"
+    "form_error_password_length": "La contraseña debe tener al menos {{value}} caracteres",
+    "anonymizer_notification": "<0>Nota:</0> La anonimización de IP está habilitada. Puedes deshabilitarla en <1>Configuración general</1>."
 }

client/src/__locales/fi.json

@@ -635,5 +635,6 @@
     "parental_control": "Lapsilukko",
     "safe_browsing": "Turvallinen selaus",
     "served_from_cache": "{{value}} <i>(jaettu välimuistista)</i>",
-    "form_error_password_length": "Salasanan on oltava ainakin {{value}} merkkiä"
+    "form_error_password_length": "Salasanan on oltava ainakin {{value}} merkkiä",
+    "anonymizer_notification": "<0>Huomioi:</0> IP-osoitteen anonymisointi on käytössä. Voit poistaa sen käytöstä <1>Yleisistä asetuksista</1>."
 }

client/src/__locales/fr.json

@@ -635,5 +635,6 @@
     "parental_control": "Contrôle parental",
     "safe_browsing": "Navigation sécurisée",
     "served_from_cache": "{{value}} <i>(depuis le cache)</i>",
-    "form_error_password_length": "Le mot de passe doit comporter au moins {{value}} caractères"
+    "form_error_password_length": "Le mot de passe doit comporter au moins {{value}} caractères",
+    "anonymizer_notification": "<0>Note :</0> L'anonymisation IP est activée. Vous pouvez la désactiver dans les <1>paramètres généraux</1>."
 }

client/src/__locales/hr.json

@@ -635,5 +635,6 @@
     "parental_control": "Roditeljska zaštita",
     "safe_browsing": "Sigurno surfanje",
     "served_from_cache": "{{value}} <i>(dohvaćeno iz predmemorije)</i>",
-    "form_error_password_length": "Lozinka mora imati najmanje {{value}} znakova"
+    "form_error_password_length": "Lozinka mora imati najmanje {{value}} znakova",
+    "anonymizer_notification": "<0>Napomena:</0>IP anonimizacija je omogućena. Možete ju onemogućiti u <1>općim postavkama</1>."
 }

client/src/__locales/hu.json

@@ -635,5 +635,6 @@
     "parental_control": "Szülői felügyelet",
     "safe_browsing": "Biztonságos böngészés",
     "served_from_cache": "{{value}} <i>(gyorsítótárból kiszolgálva)</i>",
-    "form_error_password_length": "A jelszó legalább {{value}} karakter hosszú kell, hogy legyen"
+    "form_error_password_length": "A jelszó legalább {{value}} karakter hosszú kell, hogy legyen",
+    "anonymizer_notification": "<0>Megjegyzés:</0> Az IP anonimizálás engedélyezve van. Az <1>Általános beállításoknál letilthatja</1> ."
 }

client/src/__locales/id.json

@@ -635,5 +635,6 @@
     "parental_control": "Kontrol Orang Tua",
     "safe_browsing": "Penjelajahan Aman",
     "served_from_cache": "{{value}} <i>(disajikan dari cache)</i>",
-    "form_error_password_length": "Kata sandi harus minimal {{value}} karakter"
+    "form_error_password_length": "Kata sandi harus minimal {{value}} karakter",
+    "anonymizer_notification": "<0>Catatan:</0> Anonimisasi IP diaktifkan. Anda dapat menonaktifkannya di <1>Pengaturan umum</1> ."
 }

client/src/__locales/it.json

@@ -635,5 +635,6 @@
     "parental_control": "Controllo Parentale",
     "safe_browsing": "Navigazione Sicura",
     "served_from_cache": "{{value}} <i>(fornito dalla cache)</i>",
-    "form_error_password_length": "La password deve contenere almeno {{value}} caratteri"
+    "form_error_password_length": "La password deve contenere almeno {{value}} caratteri",
+    "anonymizer_notification": "<0>Attenzione:</0> L'anonimizzazione dell'IP è abilitata. Puoi disabilitarla in <1>Impostazioni generali</1>."
 }

client/src/__locales/ja.json

@@ -635,5 +635,6 @@
     "parental_control": "ペアレンタルコントロール",
     "safe_browsing": "セーフブラウジング",
     "served_from_cache": "{{value}} <i>(キャッシュから応答)</i>",
-    "form_error_password_length": "パスワードは{{value}}文字以上にしてください"
+    "form_error_password_length": "パスワードは{{value}}文字以上にしてください",
+    "anonymizer_notification": "【<0>注意</0>】IPの匿名化が有効になっています。 <1>一般設定</1>で無効にできます。"
 }

client/src/__locales/ko.json

@@ -635,5 +635,6 @@
     "parental_control": "자녀 보호",
     "safe_browsing": "세이프 브라우징",
     "served_from_cache": "{{value}} <i>(캐시에서 제공)</i>",
-    "form_error_password_length": "비밀번호는 {{value}}자 이상이어야 합니다"
+    "form_error_password_length": "비밀번호는 {{value}}자 이상이어야 합니다",
+    "anonymizer_notification": "<0>참고:</0> IP 익명화가 활성화되었습니다. <1>일반 설정</1>에서 비활성화할 수 있습니다."
 }

client/src/__locales/nl.json

@@ -557,7 +557,7 @@
     "fastest_addr_desc": "Alle DNS-servers bevragen en het snelste IP adres terugkoppelen. Dit zal de DNS verzoeken vertragen omdat AdGuard Home moet wachten op de antwoorden van alles DNS-servers, maar verbetert wel de connectiviteit.",
     "autofix_warning_text": "Als je op \"Repareren\" klikt, configureert AdGuard Home jouw systeem om de AdGuard Home DNS-server te gebruiken.",
     "autofix_warning_list": "De volgende taken worden uitgevoerd: <0> Deactiveren van Systeem DNSStubListener</0> <0> DNS-serveradres instellen op 127.0.0.1 </0> <0> Symbolisch koppelingsdoel van /etc/resolv.conf vervangen door /run/systemd/resolve/resolv.conf </0> <0> Stop DNSStubListener (herlaad systemd-resolved service) </0>",
-    "autofix_warning_result": "Als gevolg hiervan worden alle DNS-verzoeken van je systeem standaard door AdGuard Home verwerkt.",
+    "autofix_warning_result": "Als gevolg hiervan worden alle DNS-aanvragen van je systeem standaard door AdGuard Home verwerkt.",
     "tags_title": "Labels",
     "tags_desc": "Je kunt labels selecteren die overeenkomen met de client. Labels kunnen worden opgenomen in de filterregels om ze \n nauwkeuriger toe te passen. <0>Meer informatie</0>.",
     "form_select_tags": "Client tags selecteren",
@@ -628,12 +628,13 @@
     "original_response": "Oorspronkelijke reactie",
     "click_to_view_queries": "Klik om queries te bekijken",
     "port_53_faq_link": "Poort 53 wordt vaak gebruikt door services als DNSStubListener- of de systeem DNS-resolver. Lees a.u.b. <0>deze instructie</0> hoe dit is op te lossen.",
-    "adg_will_drop_dns_queries": "AdGuard Home zal alle DNS-verzoeken van deze cliënt laten vervallen.",
+    "adg_will_drop_dns_queries": "AdGuard Home zal alle DNS-aanvragen van deze cliënt laten vervallen.",
     "filter_allowlist": "WAARSCHUWING: Deze actie zal ook de regel \"{{disallowed_rule}}\" uitsluiten van de lijst met toegestane clients.",
     "last_rule_in_allowlist": "Kan deze client niet weigeren omdat het uitsluiten van de regel \"{{disallowed_rule}}\" de lijst \"Toegestane clients\" zal UITSCHAKELEN.",
     "use_saved_key": "De eerder opgeslagen sleutel gebruiken",
     "parental_control": "Ouderlijk toezicht",
     "safe_browsing": "Veilig browsen",
     "served_from_cache": "{{value}} <i>(geleverd vanuit cache)</i>",
-    "form_error_password_length": "Wachtwoord moet minimaal {{value}} tekens lang zijn"
+    "form_error_password_length": "Wachtwoord moet minimaal {{value}} tekens lang zijn",
+    "anonymizer_notification": "<0>Opmerking:</0> IP-anonimisering is ingeschakeld. Je kunt het uitschakelen in <1>Algemene instellingen</1>."
 }

client/src/__locales/pl.json

@@ -635,5 +635,6 @@
     "parental_control": "Kontrola rodzicielska",
     "safe_browsing": "Bezpieczne przeglądanie",
     "served_from_cache": "{{value}} <i>(podawane z pamięci podręcznej)</i>",
-    "form_error_password_length": "Hasło musi mieć co najmniej {{value}} znaków"
+    "form_error_password_length": "Hasło musi mieć co najmniej {{value}} znaków",
+    "anonymizer_notification": "<0>Uwaga:</0> Anonimizacja IP jest włączona. Możesz ją wyłączyć w <1>Ustawieniach ogólnych</1>."
 }

client/src/__locales/pt-br.json

@@ -635,5 +635,6 @@
     "parental_control": "Controle parental",
     "safe_browsing": "Navegação segura",
     "served_from_cache": "{{value}} <i>(servido do cache)</i>",
-    "form_error_password_length": "A senha deve ter pelo menos {{value}} caracteres"
+    "form_error_password_length": "A senha deve ter pelo menos {{value}} caracteres",
+    "anonymizer_notification": "<0>Observação:</0> A anonimização de IP está ativada. Você pode desativá-lo em <1>Configurações gerais</1>."
 }

client/src/__locales/pt-pt.json

@@ -635,5 +635,6 @@
     "parental_control": "Controlo parental",
     "safe_browsing": "Navegação segura",
     "served_from_cache": "{{value}} <i>(servido do cache)</i>",
-    "form_error_password_length": "A palavra-passe deve ter pelo menos {{value}} caracteres"
+    "form_error_password_length": "A palavra-passe deve ter pelo menos {{value}} caracteres",
+    "anonymizer_notification": "<0>Observação:</0> A anonimização de IP está ativada. Você pode desativá-la em <1>Definições gerais</1>."
 }

client/src/__locales/ro.json

@@ -635,5 +635,6 @@
     "parental_control": "Control Parental",
     "safe_browsing": "Navigare în siguranță",
     "served_from_cache": "{{value}} <i>(furnizat din cache)</i>",
-    "form_error_password_length": "Parola trebuie să aibă cel puțin {{value}} caractere"
+    "form_error_password_length": "Parola trebuie să aibă cel puțin {{value}} caractere",
+    "anonymizer_notification": "<0>Nota:</0> Anonimizarea IP este activată. Puteți să o dezactivați în <1>Setări generale</1>."
 }

client/src/__locales/ru.json

@@ -635,5 +635,6 @@
     "parental_control": "Родительский контроль",
     "safe_browsing": "Безопасный интернет",
     "served_from_cache": "{{value}} <i>(получено из кеша)</i>",
-    "form_error_password_length": "Пароль должен быть длиной не меньше {{value}} символов"
+    "form_error_password_length": "Пароль должен быть длиной не меньше {{value}} символов",
+    "anonymizer_notification": "<0>Внимание:</0> включена анонимизация IP-адресов. Вы можете отключить её в разделе <1>Основные настройки</1>."
 }

client/src/__locales/sk.json

@@ -635,5 +635,6 @@
     "parental_control": "Rodičovská kontrola",
     "safe_browsing": "Bezpečné prehliadanie",
     "served_from_cache": "{{value}} <i>(prevzatá z cache pamäte)</i>",
-    "form_error_password_length": "Heslo musí mať dĺžku aspoň {{value}} znakov"
+    "form_error_password_length": "Heslo musí mať dĺžku aspoň {{value}} znakov",
+    "anonymizer_notification": "<0>Poznámka:</0> Anonymizácia IP je zapnutá. Môžete ju vypnúť vo <1>Všeobecných nastaveniach</1>."
 }

client/src/__locales/sl.json

@@ -635,5 +635,6 @@
     "parental_control": "Starševski nadzor",
     "safe_browsing": "Varno brskanje",
     "served_from_cache": "{{value}} <i>(postreženo iz predpomnilnika)</i>",
-    "form_error_password_length": "Geslo mora vsebovati najmanj {{value}} znakov"
+    "form_error_password_length": "Geslo mora vsebovati najmanj {{value}} znakov",
+    "anonymizer_notification": "<0>Opomba:</0> Anonimizacija IP je omogočena. Onemogočite ga lahko v <1>Splošnih nastavitvah</1>."
 }

client/src/__locales/sr-cs.json

@@ -635,5 +635,6 @@
     "parental_control": "Roditeljska kontrola",
     "safe_browsing": "Sigurno pregledanje",
     "served_from_cache": "{{value}} <i>(posluženo iz predmemorije)</i>",
-    "form_error_password_length": "Lozinka mora imati najmanje {{value}} znakova"
+    "form_error_password_length": "Lozinka mora imati najmanje {{value}} znakova",
+    "anonymizer_notification": "<0>Nota:</0> IP prepoznavanje je omogućeno. Možete ga onemogućiti u opštim <1>postavkama</1>."
 }

client/src/__locales/sv.json

@@ -635,5 +635,6 @@
     "parental_control": "Föräldrakontroll",
     "safe_browsing": "Säker surfning",
     "served_from_cache": "{{value}} <i>(levereras från cache)</i>",
-    "form_error_password_length": "Lösenordet måste vara minst {{value}} tecken långt"
+    "form_error_password_length": "Lösenordet måste vara minst {{value}} tecken långt",
+    "anonymizer_notification": "<0>Observera:</0> IP-anonymisering är aktiverad. Du kan inaktivera den i <1>Allmänna inställningar</1>."
 }

client/src/__locales/tr.json

@@ -368,7 +368,7 @@
     "encryption_server_enter": "Alan adınızı girin",
     "encryption_server_desc": "Ayarlanırsa, AdGuard Home ClientID'leri algılar, DDR sorgularına yanıt verir ve ek bağlantı doğrulamaları gerçekleştirir. Ayarlanmazsa, bu özellikler devre dışı bırakılır. Sertifikadaki DNS Adlarından biriyle eşleşmelidir.",
     "encryption_redirect": "Otomatik olarak HTTPS'e yönlendir",
-    "encryption_redirect_desc": "Etkinleştirirseniz, AdGuard Home sizi HTTP adresi yerine HTTPS adresine yönlendirir.",
+    "encryption_redirect_desc": "İşaretlenirse, AdGuard Home sizi otomatik olarak HTTP adresinden HTTPS adreslerine yönlendirecektir.",
     "encryption_https": "HTTPS bağlantı noktası",
     "encryption_https_desc": "HTTPS bağlantı noktası yapılandırılırsa, AdGuard Home yönetici arayüzüne HTTPS aracılığıyla erişilebilir olacak ve ayrıca '/dns-query' üzerinden DNS-over-HTTPS bağlantısı sağlayacaktır.",
     "encryption_dot": "DNS-over-TLS bağlantı noktası",
@@ -408,7 +408,7 @@
     "fix": "Düzelt",
     "dns_providers": "Aralarından seçim yapabileceğiniz, bilinen <0>DNS sağlayıcıların listesi</0>.",
     "update_now": "Şimdi güncelle",
-    "update_failed": "Otomatik güncelleme başarısız oldu. Elle güncellemek için lütfen <a>bu adımları uygulayın</a>.",
+    "update_failed": "Otomatik güncelleme başarısız oldu. Elle güncellemek için lütfen <a>bu adımları izleyin</a>.",
     "manual_update": "Elle güncellemek için lütfen <a>bu adımları uygulayın</a>.",
     "processing_update": "Lütfen bekleyin, AdGuard Home güncelleniyor",
     "clients_title": "Kalıcı istemciler",
@@ -635,5 +635,6 @@
     "parental_control": "Ebeveyn Denetimi",
     "safe_browsing": "Güvenli Gezinti",
     "served_from_cache": "{{value}} <i>(önbellekten kullanıldı)</i>",
-    "form_error_password_length": "Parola en az {{value}} karakter uzunluğunda olmalıdır"
+    "form_error_password_length": "Parola en az {{value}} karakter uzunluğunda olmalıdır",
+    "anonymizer_notification": "<0>Not:</0> IP anonimleştirme etkinleştirildi. Bunu <1>Genel ayarlardan</1> devre dışı bırakabilirsiniz."
 }

client/src/__locales/uk.json

@@ -635,5 +635,6 @@
     "parental_control": "Батьківський контроль",
     "safe_browsing": "Безпечний перегляд",
     "served_from_cache": "{{value}} <i>(отримано з кешу)</i>",
-    "form_error_password_length": "Пароль мусить мати принаймні {{value}} символів"
+    "form_error_password_length": "Пароль мусить мати принаймні {{value}} символів",
+    "anonymizer_notification": "<0>Примітка:</0> IP-анонімізацію ввімкнено. Ви можете вимкнути його в <1>Загальні налаштування</1> ."
 }

client/src/__locales/vi.json

@@ -635,5 +635,6 @@
     "parental_control": "Quản lý của phụ huynh",
     "safe_browsing": "Duyệt web an toàn",
     "served_from_cache": "{{value}} <i>(được phục vụ từ bộ nhớ cache)</i>",
-    "form_error_password_length": "Mật khẩu phải có ít nhất {{value}} ký tự"
+    "form_error_password_length": "Mật khẩu phải có ít nhất {{value}} ký tự",
+    "anonymizer_notification": "<0> Lưu ý:</0> Tính năng ẩn danh IP được bật. Bạn có thể tắt nó trong <1> Cài đặt chung</1>."
 }

client/src/__locales/zh-cn.json

@@ -635,5 +635,6 @@
     "parental_control": "家长控制",
     "safe_browsing": "安全浏览",
     "served_from_cache": "{{value}}<i>(由缓存提供)</i>",
-    "form_error_password_length": "密码必须至少有 {{value}} 个字符"
+    "form_error_password_length": "密码必须至少有 {{value}} 个字符",
+    "anonymizer_notification": "<0>注意：</0> IP 匿名化已启用。您可以在<1>常规设置</1>中禁用它。"
 }

client/src/__locales/zh-tw.json

@@ -635,5 +635,6 @@
     "parental_control": "家長控制",
     "safe_browsing": "安全瀏覽",
     "served_from_cache": "{{value}} <i>(由快取提供)</i>",
-    "form_error_password_length": "密碼必須為至少長 {{value}} 個字元"
+    "form_error_password_length": "密碼必須為至少長 {{value}} 個字元",
+    "anonymizer_notification": "<0>注意：</0>IP 匿名化被啟用。您可在<1>一般設定</1>中禁用它。"
 }

client/src/actions/filtering.js

@@ -31,7 +31,9 @@ export const setRulesSuccess = createAction('SET_RULES_SUCCESS');
 export const setRules = (rules) => async (dispatch) => {
     dispatch(setRulesRequest());
     try {
-        const normalizedRules = normalizeRulesTextarea(rules);
+        const normalizedRules = {
+            rules: normalizeRulesTextarea(rules)?.split('\n'),
+        };
         await apiClient.setRules(normalizedRules);
         dispatch(addSuccessToast('updated_custom_filtering_toast'));
         dispatch(setRulesSuccess());

client/src/actions/index.js

@@ -355,7 +355,7 @@ export const changeLanguageSuccess = createAction('CHANGE_LANGUAGE_SUCCESS');
 export const changeLanguage = (lang) => async (dispatch) => {
     dispatch(changeLanguageRequest());
     try {
-        await apiClient.changeLanguage(lang);
+        await apiClient.changeLanguage({ language: lang });
         dispatch(changeLanguageSuccess());
     } catch (error) {
         dispatch(addErrorToast({ error }));
@@ -370,8 +370,8 @@ export const getLanguageSuccess = createAction('GET_LANGUAGE_SUCCESS');
 export const getLanguage = () => async (dispatch) => {
     dispatch(getLanguageRequest());
     try {
-        const language = await apiClient.getCurrentLanguage();
+        const langSettings = await apiClient.getCurrentLanguage();
-        dispatch(getLanguageSuccess(language));
+        dispatch(getLanguageSuccess(langSettings.language));
     } catch (error) {
         dispatch(addErrorToast({ error }));
         dispatch(getLanguageFailure());
@@ -421,7 +421,10 @@ export const findActiveDhcpFailure = createAction('FIND_ACTIVE_DHCP_FAILURE');
 export const findActiveDhcp = (name) => async (dispatch, getState) => {
     dispatch(findActiveDhcpRequest());
     try {
-        const activeDhcp = await apiClient.findActiveDhcp(name);
+        const req = {
+            interface: name,
+        };
+        const activeDhcp = await apiClient.findActiveDhcp(req);
         dispatch(findActiveDhcpSuccess(activeDhcp));
         const { check, interface_name, interfaces } = getState().dhcp;
         const selectedInterface = getState().form[FORM_NAME.DHCP_INTERFACES].values.interface_name;

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': 'text/plain' },
         };
         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);
     }
@@ -173,12 +171,7 @@ class Api {
 
     enableParentalControl() {
         const { path, method } = this.PARENTAL_ENABLE;
-        const parameter = 'sensitivity=TEEN'; // this parameter TEEN is hardcoded
+        return this.makeRequest(path, method);
-        const config = {
-            data: parameter,
-            headers: { 'Content-Type': 'text/plain' },
-        };
-        return this.makeRequest(path, method, config);
     }
 
     disableParentalControl() {
@@ -240,11 +233,10 @@ class Api {
         return this.makeRequest(path, method);
     }
 
-    changeLanguage(lang) {
+    changeLanguage(config) {
         const { path, method } = this.CHANGE_LANGUAGE;
         const parameters = {
-            data: lang,
+            data: config,
-            headers: { 'Content-Type': 'text/plain' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -280,16 +272,14 @@ class Api {
         const { path, method } = this.DHCP_SET_CONFIG;
         const parameters = {
             data: config,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, parameters);
     }
 
-    findActiveDhcp(name) {
+    findActiveDhcp(req) {
         const { path, method } = this.DHCP_FIND_ACTIVE;
         const parameters = {
-            data: name,
+            data: req,
-            headers: { 'Content-Type': 'text/plain' },
         };
         return this.makeRequest(path, method, parameters);
     }
@@ -298,7 +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);
     }
@@ -307,7 +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);
     }
@@ -338,7 +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);
     }
@@ -347,7 +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);
     }
@@ -368,7 +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);
     }
@@ -377,7 +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);
     }
@@ -402,7 +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);
     }
@@ -411,7 +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);
     }
@@ -420,7 +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);
     }
@@ -445,7 +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);
     }
@@ -466,7 +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);
     }
@@ -475,7 +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);
     }
@@ -501,7 +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);
     }
@@ -529,7 +506,6 @@ class Api {
         const { path, method } = this.STATS_CONFIG;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -565,7 +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);
     }
@@ -582,7 +557,6 @@ class Api {
         const { path, method } = this.LOGIN;
         const config = {
             data,
-            headers: { 'Content-Type': 'application/json' },
         };
         return this.makeRequest(path, method, config);
     }
@@ -609,7 +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

@@ -2,10 +2,12 @@
 package aghhttp
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
 
+	"github.com/AdguardTeam/AdGuardHome/internal/version"
 	"github.com/AdguardTeam/golibs/log"
 )
 
@@ -31,6 +33,43 @@ 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)
 }
+
+// UserAgent returns the ID of the service as a User-Agent string.  It can also
+// be used as the value of the Server HTTP header.
+func UserAgent() (ua string) {
+	return fmt.Sprintf("AdGuardHome/%s", version.Version())
+}
+
+// textPlainDeprMsg is the message returned to API users when they try to use
+// an API that used to accept "text/plain" but doesn't anymore.
+const textPlainDeprMsg = `using this api with the text/plain content-type is deprecated; ` +
+	`use application/json`
+
+// WriteTextPlainDeprecated responds to the request with a message about
+// deprecation and removal of a plain-text API if the request is made with the
+// "text/plain" content-type.
+func WriteTextPlainDeprecated(w http.ResponseWriter, r *http.Request) (isPlainText bool) {
+	if r.Header.Get(HdrNameContentType) != HdrValTextPlain {
+		return false
+	}
+
+	Error(r, w, http.StatusUnsupportedMediaType, textPlainDeprMsg)
+
+	return true
+}
+
+// WriteJSONResponse sets the content-type header in w.Header() to
+// "application/json", encodes resp to w, calls Error on any returned error, and
+// returns it as well.
+func WriteJSONResponse(w http.ResponseWriter, r *http.Request, resp any) (err error) {
+	w.Header().Set(HdrNameContentType, HdrValApplicationJSON)
+	err = json.NewEncoder(w).Encode(resp)
+	if err != nil {
+		Error(r, w, http.StatusInternalServerError, "encoding resp: %s", err)
+	}
+
+	return err
+}

internal/aghhttp/header.go

@@ -0,0 +1,22 @@
+package aghhttp
+
+// HTTP Headers
+
+// HTTP header name constants.
+//
+// TODO(a.garipov): Remove unused.
+const (
+	HdrNameAcceptEncoding           = "Accept-Encoding"
+	HdrNameAccessControlAllowOrigin = "Access-Control-Allow-Origin"
+	HdrNameContentEncoding          = "Content-Encoding"
+	HdrNameContentType              = "Content-Type"
+	HdrNameServer                   = "Server"
+	HdrNameTrailer                  = "Trailer"
+	HdrNameUserAgent                = "User-Agent"
+)
+
+// HTTP header value constants.
+const (
+	HdrValApplicationJSON = "application/json"
+	HdrValTextPlain       = "text/plain"
+)

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
+		require.True(t, ok)
-		select {
+		require.NotNil(t, upd)
-		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/aghnet/net.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"io"
 	"net"
-	"net/netip"
 	"syscall"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghos"
@@ -32,12 +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{0: 127, 3: 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.
@@ -54,31 +47,26 @@ func IfaceSetStaticIP(ifaceName string) (err error) {
 //
 // TODO(e.burkov):  Investigate if the gateway address may be fetched in another
 // way since not every machine has the software installed.
-func GatewayIP(ifaceName string) (ip netip.Addr) {
+func GatewayIP(ifaceName string) (ip net.IP) {
 	code, out, err := aghosRunCommand("ip", "route", "show", "dev", ifaceName)
 	if err != nil {
 		log.Debug("%s", err)
 
-		return ip
+		return nil
 	} else if code != 0 {
 		log.Debug("fetching gateway ip: unexpected exit code: %d", code)
 
-		return ip
+		return nil
 	}
 
 	fields := bytes.Fields(out)
 	// The meaningful "ip route" command output should contain the word
 	// "default" at first field and default gateway IP address at third field.
 	if len(fields) < 3 || string(fields[0]) != "default" {
-		return ip
+		return nil
 	}
 
-	ip, err = netip.ParseAddr(string(fields[2]))
+	return net.ParseIP(string(fields[2]))
-	if err != nil {
-		return netip.Addr{}
-	}
-
-	return ip
 }
 
 // CanBindPrivilegedPorts checks if current process can bind to privileged
@@ -90,9 +78,9 @@ func CanBindPrivilegedPorts() (can bool, err error) {
 // NetInterface represents an entry of network interfaces map.
 type NetInterface struct {
 	// Addresses are the network interface addresses.
-	Addresses []netip.Addr `json:"ip_addresses,omitempty"`
+	Addresses []net.IP `json:"ip_addresses,omitempty"`
 	// Subnets are the IP networks for this network interface.
-	Subnets      []netip.Prefix   `json:"-"`
+	Subnets      []*net.IPNet     `json:"-"`
 	Name         string           `json:"name"`
 	HardwareAddr net.HardwareAddr `json:"hardware_address"`
 	Flags        net.Flags        `json:"flags"`
@@ -113,78 +101,57 @@ func (iface NetInterface) MarshalJSON() ([]byte, error) {
 	})
 }
 
-func NetInterfaceFrom(iface *net.Interface) (niface *NetInterface, err error) {
-	niface = &NetInterface{
-		Name:         iface.Name,
-		HardwareAddr: iface.HardwareAddr,
-		Flags:        iface.Flags,
-		MTU:          iface.MTU,
-	}
-
-	addrs, err := iface.Addrs()
-	if err != nil {
-		return nil, fmt.Errorf("failed to get addresses for interface %s: %w", iface.Name, err)
-	}
-
-	// Collect network interface addresses.
-	for _, addr := range addrs {
-		n, ok := addr.(*net.IPNet)
-		if !ok {
-			// Should be *net.IPNet, this is weird.
-			return nil, fmt.Errorf("expected %[2]s to be %[1]T, got %[2]T", n, addr)
-		} else if ip4 := n.IP.To4(); ip4 != nil {
-			n.IP = ip4
-		}
-
-		ip, ok := netip.AddrFromSlice(n.IP)
-		if !ok {
-			return nil, fmt.Errorf("bad address %s", n.IP)
-		}
-
-		if ip.IsLinkLocalUnicast() {
-			// Ignore link-local IPv4.
-			if ip.Is4() {
-				continue
-			}
-
-			ip = ip.WithZone(iface.Name)
-		}
-
-		ones, _ := n.Mask.Size()
-		p := netip.PrefixFrom(ip, ones)
-
-		niface.Addresses = append(niface.Addresses, ip)
-		niface.Subnets = append(niface.Subnets, p)
-	}
-
-	return niface, nil
-}
-
 // GetValidNetInterfacesForWeb returns interfaces that are eligible for DNS and
 // WEB only we do not return link-local addresses here.
 //
 // TODO(e.burkov):  Can't properly test the function since it's nontrivial to
 // substitute net.Interface.Addrs and the net.InterfaceAddrs can't be used.
-func GetValidNetInterfacesForWeb() (nifaces []*NetInterface, err error) {
+func GetValidNetInterfacesForWeb() (netIfaces []*NetInterface, err error) {
 	ifaces, err := net.Interfaces()
 	if err != nil {
-		return nil, fmt.Errorf("getting interfaces: %w", err)
+		return nil, fmt.Errorf("couldn't get interfaces: %w", err)
 	} else if len(ifaces) == 0 {
-		return nil, errors.Error("no legible interfaces")
+		return nil, errors.Error("couldn't find any legible interface")
 	}
 
-	for i := range ifaces {
+	for _, iface := range ifaces {
-		var niface *NetInterface
+		var addrs []net.Addr
-		niface, err = NetInterfaceFrom(&ifaces[i])
+		addrs, err = iface.Addrs()
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("failed to get addresses for interface %s: %w", iface.Name, err)
-		} else if len(niface.Addresses) != 0 {
+		}
-			// Discard interfaces with no addresses.
+
-			nifaces = append(nifaces, niface)
+		netIface := &NetInterface{
+			MTU:          iface.MTU,
+			Name:         iface.Name,
+			HardwareAddr: iface.HardwareAddr,
+			Flags:        iface.Flags,
+		}
+
+		// Collect network interface addresses.
+		for _, addr := range addrs {
+			ipNet, ok := addr.(*net.IPNet)
+			if !ok {
+				// Should be net.IPNet, this is weird.
+				return nil, fmt.Errorf("got %s that is not net.IPNet, it is %T", addr, addr)
+			}
+
+			// Ignore link-local.
+			if ipNet.IP.IsLinkLocalUnicast() {
+				continue
+			}
+
+			netIface.Addresses = append(netIface.Addresses, ipNet.IP)
+			netIface.Subnets = append(netIface.Subnets, ipNet)
+		}
+
+		// Discard interfaces with no addresses.
+		if len(netIface.Addresses) != 0 {
+			netIfaces = append(netIfaces, netIface)
 		}
 	}
 
-	return nifaces, nil
+	return netIfaces, nil
 }
 
 // InterfaceByIP returns the name of the interface bound to ip.
@@ -193,7 +160,7 @@ func GetValidNetInterfacesForWeb() (nifaces []*NetInterface, err error) {
 // IP address can be shared by multiple interfaces in some configurations.
 //
 // TODO(e.burkov):  See TODO on GetValidNetInterfacesForWeb.
-func InterfaceByIP(ip netip.Addr) (ifaceName string) {
+func InterfaceByIP(ip net.IP) (ifaceName string) {
 	ifaces, err := GetValidNetInterfacesForWeb()
 	if err != nil {
 		return ""
@@ -201,7 +168,7 @@ func InterfaceByIP(ip netip.Addr) (ifaceName string) {
 
 	for _, iface := range ifaces {
 		for _, addr := range iface.Addresses {
-			if ip == addr {
+			if ip.Equal(addr) {
 				return iface.Name
 			}
 		}
@@ -210,16 +177,15 @@ func InterfaceByIP(ip netip.Addr) (ifaceName string) {
 	return ""
 }
 
-// GetSubnet returns the subnet corresponding to the interface of zero prefix if
+// GetSubnet returns pointer to net.IPNet for the specified interface or nil if
 // the search fails.
 //
 // TODO(e.burkov):  See TODO on GetValidNetInterfacesForWeb.
-func GetSubnet(ifaceName string) (p netip.Prefix) {
+func GetSubnet(ifaceName string) *net.IPNet {
 	netIfaces, err := GetValidNetInterfacesForWeb()
 	if err != nil {
 		log.Error("Could not get network interfaces info: %v", err)
-
+		return nil
-		return p
 	}
 
 	for _, netIface := range netIfaces {
@@ -228,14 +194,14 @@ func GetSubnet(ifaceName string) (p netip.Prefix) {
 		}
 	}
 
-	return p
+	return nil
 }
 
 // CheckPort checks if the port is available for binding.  network is expected
 // to be one of "udp" and "tcp".
-func CheckPort(network string, ipp netip.AddrPort) (err error) {
+func CheckPort(network string, ip net.IP, port int) (err error) {
 	var c io.Closer
-	addr := ipp.String()
+	addr := netutil.IPPort{IP: ip, Port: port}.String()
 	switch network {
 	case "tcp":
 		c, err = net.Listen(network, addr)

internal/aghnet/net_linux.go

@@ -6,7 +6,7 @@ import (
 	"bufio"
 	"fmt"
 	"io"
-	"net/netip"
+	"net"
 	"os"
 	"strings"
 
@@ -151,7 +151,7 @@ func findIfaceLine(s *bufio.Scanner, name string) (ok bool) {
 // interface through dhcpcd.conf.
 func ifaceSetStaticIP(ifaceName string) (err error) {
 	ipNet := GetSubnet(ifaceName)
-	if !ipNet.Addr().IsValid() {
+	if ipNet.IP == nil {
 		return errors.Error("can't get IP address")
 	}
 
@@ -174,7 +174,7 @@ func ifaceSetStaticIP(ifaceName string) (err error) {
 
 // dhcpcdConfIface returns configuration lines for the dhcpdc.conf files that
 // configure the interface to have a static IP.
-func dhcpcdConfIface(ifaceName string, subnet netip.Prefix, gateway netip.Addr) (conf string) {
+func dhcpcdConfIface(ifaceName string, ipNet *net.IPNet, gwIP net.IP) (conf string) {
 	b := &strings.Builder{}
 	stringutil.WriteToBuilder(
 		b,
@@ -183,15 +183,15 @@ func dhcpcdConfIface(ifaceName string, subnet netip.Prefix, gateway netip.Addr)
 		" added by AdGuard Home.\ninterface ",
 		ifaceName,
 		"\nstatic ip_address=",
-		subnet.String(),
+		ipNet.String(),
 		"\n",
 	)
 
-	if gateway.IsValid() {
+	if gwIP != nil {
-		stringutil.WriteToBuilder(b, "static routers=", gateway.String(), "\n")
+		stringutil.WriteToBuilder(b, "static routers=", gwIP.String(), "\n")
 	}
 
-	stringutil.WriteToBuilder(b, "static domain_name_servers=", subnet.Addr().String(), "\n\n")
+	stringutil.WriteToBuilder(b, "static domain_name_servers=", ipNet.IP.String(), "\n\n")
 
 	return b.String()
 }

internal/aghnet/net_test.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"io/fs"
 	"net"
-	"net/netip"
 	"os"
 	"strings"
 	"testing"
@@ -94,34 +93,34 @@ func TestGatewayIP(t *testing.T) {
 	const cmd = "ip route show dev " + ifaceName
 
 	testCases := []struct {
-		shell mapShell
-		want  netip.Addr
 		name  string
+		shell mapShell
+		want  net.IP
 	}{{
-		shell: theOnlyCmd(cmd, 0, `default via 1.2.3.4 onlink`, nil),
-		want:  netip.AddrFrom4([4]byte{1, 2, 3, 4}),
 		name:  "success_v4",
+		shell: theOnlyCmd(cmd, 0, `default via 1.2.3.4 onlink`, nil),
+		want:  net.IP{1, 2, 3, 4}.To16(),
 	}, {
+		name:  "success_v6",
 		shell: theOnlyCmd(cmd, 0, `default via ::ffff onlink`, nil),
-		want: netip.AddrFrom16([16]byte{
+		want: net.IP{
 			0x0, 0x0, 0x0, 0x0,
 			0x0, 0x0, 0x0, 0x0,
 			0x0, 0x0, 0x0, 0x0,
 			0x0, 0x0, 0xFF, 0xFF,
-		}),
+		},
-		name: "success_v6",
 	}, {
-		shell: theOnlyCmd(cmd, 0, `non-default via 1.2.3.4 onlink`, nil),
-		want:  netip.Addr{},
 		name:  "bad_output",
+		shell: theOnlyCmd(cmd, 0, `non-default via 1.2.3.4 onlink`, nil),
+		want:  nil,
 	}, {
-		shell: theOnlyCmd(cmd, 0, "", errors.Error("can't run command")),
-		want:  netip.Addr{},
 		name:  "err_runcmd",
+		shell: theOnlyCmd(cmd, 0, "", errors.Error("can't run command")),
+		want:  nil,
 	}, {
-		shell: theOnlyCmd(cmd, 1, "", nil),
-		want:  netip.Addr{},
 		name:  "bad_code",
+		shell: theOnlyCmd(cmd, 1, "", nil),
+		want:  nil,
 	}}
 
 	for _, tc := range testCases {
@@ -199,21 +198,17 @@ func TestBroadcastFromIPNet(t *testing.T) {
 }
 
 func TestCheckPort(t *testing.T) {
-	laddr := netip.AddrPortFrom(IPv4Localhost(), 0)
-
 	t.Run("tcp_bound", func(t *testing.T) {
-		l, err := net.Listen("tcp", laddr.String())
+		l, err := net.Listen("tcp", "127.0.0.1:")
 		require.NoError(t, err)
 		testutil.CleanupAndRequireSuccess(t, l.Close)
 
-		addr := l.Addr()
+		ipp := netutil.IPPortFromAddr(l.Addr())
-		require.IsType(t, new(net.TCPAddr), addr)
+		require.NotNil(t, ipp)
+		require.NotNil(t, ipp.IP)
+		require.NotZero(t, ipp.Port)
 
-		ipp := addr.(*net.TCPAddr).AddrPort()
+		err = CheckPort("tcp", ipp.IP, ipp.Port)
-		require.Equal(t, laddr.Addr(), ipp.Addr())
-		require.NotZero(t, ipp.Port())
-
-		err = CheckPort("tcp", ipp)
 		target := &net.OpError{}
 		require.ErrorAs(t, err, &target)
 
@@ -221,18 +216,16 @@ func TestCheckPort(t *testing.T) {
 	})
 
 	t.Run("udp_bound", func(t *testing.T) {
-		conn, err := net.ListenPacket("udp", laddr.String())
+		conn, err := net.ListenPacket("udp", "127.0.0.1:")
 		require.NoError(t, err)
 		testutil.CleanupAndRequireSuccess(t, conn.Close)
 
-		addr := conn.LocalAddr()
+		ipp := netutil.IPPortFromAddr(conn.LocalAddr())
-		require.IsType(t, new(net.UDPAddr), addr)
+		require.NotNil(t, ipp)
+		require.NotNil(t, ipp.IP)
+		require.NotZero(t, ipp.Port)
 
-		ipp := addr.(*net.UDPAddr).AddrPort()
+		err = CheckPort("udp", ipp.IP, ipp.Port)
-		require.Equal(t, laddr.Addr(), ipp.Addr())
-		require.NotZero(t, ipp.Port())
-
-		err = CheckPort("udp", ipp)
 		target := &net.OpError{}
 		require.ErrorAs(t, err, &target)
 
@@ -240,12 +233,12 @@ func TestCheckPort(t *testing.T) {
 	})
 
 	t.Run("bad_network", func(t *testing.T) {
-		err := CheckPort("bad_network", netip.AddrPortFrom(netip.Addr{}, 0))
+		err := CheckPort("bad_network", nil, 0)
 		assert.NoError(t, err)
 	})
 
 	t.Run("can_bind", func(t *testing.T) {
-		err := CheckPort("udp", netip.AddrPortFrom(netip.IPv4Unspecified(), 0))
+		err := CheckPort("udp", net.IP{0, 0, 0, 0}, 0)
 		assert.NoError(t, err)
 	})
 }
@@ -329,18 +322,18 @@ func TestNetInterface_MarshalJSON(t *testing.T) {
 		`"mtu":1500` +
 		`}` + "\n"
 
-	ip4, ok := netip.AddrFromSlice([]byte{1, 2, 3, 4})
+	ip4, ip6 := net.IP{1, 2, 3, 4}, net.IP{0xAA, 0xAA, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
-	require.True(t, ok)
+	mask4, mask6 := net.CIDRMask(24, netutil.IPv4BitLen), net.CIDRMask(8, netutil.IPv6BitLen)
-
-	ip6, ok := netip.AddrFromSlice([]byte{0xAA, 0xAA, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1})
-	require.True(t, ok)
-
-	net4 := netip.PrefixFrom(ip4, 24)
-	net6 := netip.PrefixFrom(ip6, 8)
 
 	iface := &NetInterface{
-		Addresses:    []netip.Addr{ip4, ip6},
+		Addresses: []net.IP{ip4, ip6},
-		Subnets:      []netip.Prefix{net4, net6},
+		Subnets: []*net.IPNet{{
+			IP:   ip4.Mask(mask4),
+			Mask: mask4,
+		}, {
+			IP:   ip6.Mask(mask6),
+			Mask: mask6,
+		}},
 		Name:         "iface0",
 		HardwareAddr: net.HardwareAddr{0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF},
 		Flags:        net.FlagUp | net.FlagMulticast,

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/dhcpd/http_unix.go

@@ -5,11 +5,9 @@ package dhcpd
 import (
 	"encoding/json"
 	"fmt"
-	"io"
 	"net"
 	"net/http"
 	"os"
-	"strings"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghalg"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
@@ -349,8 +347,6 @@ func (s *server) handleDHCPInterfaces(w http.ResponseWriter, r *http.Request) {
 				return
 			}
 			// ignore link-local
-			//
-			// TODO(e.burkov):  Try to listen DHCP on LLA as well.
 			if ipnet.IP.IsLinkLocalUnicast() {
 				continue
 			}
@@ -361,7 +357,7 @@ func (s *server) handleDHCPInterfaces(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 		if len(jsonIface.Addrs4)+len(jsonIface.Addrs6) != 0 {
-			jsonIface.GatewayIP = aghnet.GatewayIP(iface.Name).AsSlice()
+			jsonIface.GatewayIP = aghnet.GatewayIP(iface.Name)
 			response[iface.Name] = jsonIface
 		}
 	}
@@ -412,31 +408,37 @@ type dhcpSearchResult struct {
 	V6 dhcpSearchV6Result `json:"v6"`
 }
 
-// Perform the following tasks:
+// findActiveServerReq is the JSON structure for the request to find active DHCP
-// . Search for another DHCP server running
+// servers.
-// . Check if a static IP is configured for the network interface
+type findActiveServerReq struct {
-// Respond with results
+	Interface string `json:"interface"`
+}
+
+// handleDHCPFindActiveServer performs the following tasks:
+//  1. searches for another DHCP server in the network;
+//  2. check if a static IP is configured for the network interface;
+//  3. responds with the results.
 func (s *server) handleDHCPFindActiveServer(w http.ResponseWriter, r *http.Request) {
-	// This use of ReadAll is safe, because request's body is now limited.
+	if aghhttp.WriteTextPlainDeprecated(w, r) {
-	body, err := io.ReadAll(r.Body)
+		return
+	}
+
+	req := &findActiveServerReq{}
+	err := json.NewDecoder(r.Body).Decode(req)
 	if err != nil {
-		msg := fmt.Sprintf("failed to read request body: %s", err)
+		aghhttp.Error(r, w, http.StatusBadRequest, "reading req: %s", err)
-		log.Error(msg)
-		http.Error(w, msg, http.StatusBadRequest)
 
 		return
 	}
 
-	ifaceName := strings.TrimSpace(string(body))
+	ifaceName := req.Interface
 	if ifaceName == "" {
-		msg := "empty interface name specified"
+		aghhttp.Error(r, w, http.StatusBadRequest, "empty interface name")
-		log.Error(msg)
-		http.Error(w, msg, http.StatusBadRequest)
 
 		return
 	}
 
-	result := dhcpSearchResult{
+	result := &dhcpSearchResult{
 		V4: dhcpSearchV4Result{
 			OtherServer: dhcpSearchOtherResult{
 				Found: "no",
@@ -461,6 +463,14 @@ func (s *server) handleDHCPFindActiveServer(w http.ResponseWriter, r *http.Reque
 		result.V4.StaticIP.IP = aghnet.GetSubnet(ifaceName).String()
 	}
 
+	setOtherDHCPResult(ifaceName, result)
+
+	_ = aghhttp.WriteJSONResponse(w, r, result)
+}
+
+// setOtherDHCPResult sets the results of the check for another DHCP server in
+// result.
+func setOtherDHCPResult(ifaceName string, result *dhcpSearchResult) {
 	found4, found6, err4, err6 := aghnet.CheckOtherDHCP(ifaceName)
 	if err4 != nil {
 		result.V4.OtherServer.Found = "error"
@@ -468,24 +478,13 @@ func (s *server) handleDHCPFindActiveServer(w http.ResponseWriter, r *http.Reque
 	} else if found4 {
 		result.V4.OtherServer.Found = "yes"
 	}
+
 	if err6 != nil {
 		result.V6.OtherServer.Found = "error"
 		result.V6.OtherServer.Error = err6.Error()
 	} else if found6 {
 		result.V6.OtherServer.Found = "yes"
 	}
-
-	w.Header().Set("Content-Type", "application/json")
-	err = json.NewEncoder(w).Encode(result)
-	if err != nil {
-		aghhttp.Error(
-			r,
-			w,
-			http.StatusInternalServerError,
-			"Failed to marshal DHCP found json: %s",
-			err,
-		)
-	}
 }
 
 func (s *server) handleDHCPAddStaticLease(w http.ResponseWriter, r *http.Request) {

internal/filtering/http.go

@@ -3,13 +3,11 @@ package filtering
 import (
 	"encoding/json"
 	"fmt"
-	"io"
 	"net"
 	"net/http"
 	"net/url"
 	"os"
 	"path/filepath"
-	"strings"
 	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
@@ -249,16 +247,25 @@ func (d *DNSFilter) handleFilteringSetURL(w http.ResponseWriter, r *http.Request
 	}
 }
 
+// filteringRulesReq is the JSON structure for settings custom filtering rules.
+type filteringRulesReq struct {
+	Rules []string `json:"rules"`
+}
+
 func (d *DNSFilter) handleFilteringSetRules(w http.ResponseWriter, r *http.Request) {
-	// This use of ReadAll is safe, because request's body is now limited.
+	if aghhttp.WriteTextPlainDeprecated(w, r) {
-	body, err := io.ReadAll(r.Body)
+		return
+	}
+
+	req := &filteringRulesReq{}
+	err := json.NewDecoder(r.Body).Decode(req)
 	if err != nil {
-		aghhttp.Error(r, w, http.StatusBadRequest, "Failed to read request body: %s", err)
+		aghhttp.Error(r, w, http.StatusBadRequest, "reading req: %s", err)
 
 		return
 	}
 
-	d.UserRules = strings.Split(string(body), "\n")
+	d.UserRules = req.Rules
 	d.ConfigModified()
 	d.EnableFilters(true)
 }

internal/home/auth.go

@@ -8,12 +8,14 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"path"
 	"strconv"
 	"strings"
 	"sync"
 	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
+	"github.com/AdguardTeam/golibs/errors"
 	"github.com/AdguardTeam/golibs/log"
 	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/AdguardTeam/golibs/timeutil"
@@ -32,7 +34,8 @@ const sessionTokenSize = 16
 
 type session struct {
 	userName string
-	expire   uint32 // expiration time (in seconds)
+	// expire is the expiration time, in seconds.
+	expire uint32
 }
 
 func (s *session) serialize() []byte {
@@ -64,29 +67,29 @@ func (s *session) deserialize(data []byte) bool {
 
 // Auth - global object
 type Auth struct {
-	db         *bbolt.DB
+	db          *bbolt.DB
-	blocker    *authRateLimiter
+	raleLimiter *authRateLimiter
-	sessions   map[string]*session
+	sessions    map[string]*session
-	users      []User
+	users       []webUser
-	lock       sync.Mutex
+	lock        sync.Mutex
-	sessionTTL uint32
+	sessionTTL  uint32
 }
 
-// User object
+// webUser represents a user of the Web UI.
-type User struct {
+type webUser struct {
 	Name         string `yaml:"name"`
-	PasswordHash string `yaml:"password"` // bcrypt hash
+	PasswordHash string `yaml:"password"`
 }
 
 // InitAuth - create a global object
-func InitAuth(dbFilename string, users []User, sessionTTL uint32, blocker *authRateLimiter) *Auth {
+func InitAuth(dbFilename string, users []webUser, sessionTTL uint32, rateLimiter *authRateLimiter) *Auth {
 	log.Info("Initializing auth module: %s", dbFilename)
 
 	a := &Auth{
-		sessionTTL: sessionTTL,
+		sessionTTL:  sessionTTL,
-		blocker:    blocker,
+		raleLimiter: rateLimiter,
-		sessions:   make(map[string]*session),
+		sessions:    make(map[string]*session),
-		users:      users,
+		users:       users,
 	}
 	var err error
 	a.db, err = bbolt.Open(dbFilename, 0o644, nil)
@@ -326,35 +329,25 @@ func newSessionToken() (data []byte, err error) {
 	return randData, nil
 }
 
-// cookieTimeFormat is the format to be used in (time.Time).Format for cookie's
+// newCookie creates a new authentication cookie.
-// expiry field.
+func (a *Auth) newCookie(req loginJSON, addr string) (c *http.Cookie, err error) {
-const cookieTimeFormat = "Mon, 02 Jan 2006 15:04:05 GMT"
+	rateLimiter := a.raleLimiter
-
+	u, ok := a.findUser(req.Name, req.Password)
-// cookieExpiryFormat returns the formatted exp to be used in cookie string.
+	if !ok {
-// It's quite simple for now, but probably will be expanded in the future.
+		if rateLimiter != nil {
-func cookieExpiryFormat(exp time.Time) (formatted string) {
+			rateLimiter.inc(addr)
-	return exp.Format(cookieTimeFormat)
-}
-
-func (a *Auth) httpCookie(req loginJSON, addr string) (cookie string, err error) {
-	blocker := a.blocker
-	u := a.UserFind(req.Name, req.Password)
-	if len(u.Name) == 0 {
-		if blocker != nil {
-			blocker.inc(addr)
 		}
 
-		return "", err
+		return nil, errors.Error("invalid username or password")
 	}
 
-	if blocker != nil {
+	if rateLimiter != nil {
-		blocker.remove(addr)
+		rateLimiter.remove(addr)
 	}
 
-	var sess []byte
+	sess, err := newSessionToken()
-	sess, err = newSessionToken()
 	if err != nil {
-		return "", err
+		return nil, fmt.Errorf("generating token: %w", err)
 	}
 
 	now := time.Now().UTC()
@@ -364,11 +357,15 @@ func (a *Auth) httpCookie(req loginJSON, addr string) (cookie string, err error)
 		expire:   uint32(now.Unix()) + a.sessionTTL,
 	})
 
-	return fmt.Sprintf(
+	return &http.Cookie{
-		"%s=%s; Path=/; HttpOnly; Expires=%s",
+		Name:    sessionCookieName,
-		sessionCookieName, hex.EncodeToString(sess),
+		Value:   hex.EncodeToString(sess),
-		cookieExpiryFormat(now.Add(cookieTTL)),
+		Path:    "/",
-	), nil
+		Expires: now.Add(cookieTTL),
+
+		HttpOnly: true,
+		SameSite: http.SameSiteLaxMode,
+	}, nil
 }
 
 // realIP extracts the real IP address of the client from an HTTP request using
@@ -436,8 +433,8 @@ func handleLogin(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if blocker := Context.auth.blocker; blocker != nil {
+	if rateLimiter := Context.auth.raleLimiter; rateLimiter != nil {
-		if left := blocker.check(remoteAddr); left > 0 {
+		if left := rateLimiter.check(remoteAddr); left > 0 {
 			w.Header().Set("Retry-After", strconv.Itoa(int(left.Seconds())))
 			aghhttp.Error(r, w, http.StatusTooManyRequests, "auth: blocked for %s", left)
 
@@ -445,10 +442,9 @@ func handleLogin(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	var cookie string
+	cookie, err := Context.auth.newCookie(req, remoteAddr)
-	cookie, err = Context.auth.httpCookie(req, remoteAddr)
 	if err != nil {
-		aghhttp.Error(r, w, http.StatusBadRequest, "crypto rand reader: %s", err)
+		aghhttp.Error(r, w, http.StatusForbidden, "%s", err)
 
 		return
 	}
@@ -462,20 +458,11 @@ func handleLogin(w http.ResponseWriter, r *http.Request) {
 		log.Error("auth: unknown ip")
 	}
 
-	if len(cookie) == 0 {
-		log.Info("auth: failed to login user %q from ip %v", req.Name, ip)
-
-		time.Sleep(1 * time.Second)
-
-		http.Error(w, "invalid username or password", http.StatusBadRequest)
-
-		return
-	}
-
 	log.Info("auth: user %q successfully logged in from ip %v", req.Name, ip)
 
+	http.SetCookie(w, cookie)
+
 	h := w.Header()
-	h.Set("Set-Cookie", cookie)
 	h.Set("Cache-Control", "no-store, no-cache, must-revalidate, proxy-revalidate")
 	h.Set("Pragma", "no-cache")
 	h.Set("Expires", "0")
@@ -484,17 +471,31 @@ func handleLogin(w http.ResponseWriter, r *http.Request) {
 }
 
 func handleLogout(w http.ResponseWriter, r *http.Request) {
-	cookie := r.Header.Get("Cookie")
+	respHdr := w.Header()
-	sess := parseCookie(cookie)
+	c, err := r.Cookie(sessionCookieName)
+	if err != nil {
+		// The only error that is returned from r.Cookie is [http.ErrNoCookie].
+		// The user is already logged out.
+		respHdr.Set("Location", "/login.html")
+		w.WriteHeader(http.StatusFound)
 
-	Context.auth.RemoveSession(sess)
+		return
+	}
 
-	w.Header().Set("Location", "/login.html")
+	Context.auth.RemoveSession(c.Value)
 
-	s := fmt.Sprintf("%s=; Path=/; HttpOnly; Expires=Thu, 01 Jan 1970 00:00:00 GMT",
+	c = &http.Cookie{
-		sessionCookieName)
+		Name:    sessionCookieName,
-	w.Header().Set("Set-Cookie", s)
+		Value:   "",
+		Path:    "/",
+		Expires: time.Unix(0, 0),
 
+		HttpOnly: true,
+		SameSite: http.SameSiteLaxMode,
+	}
+
+	respHdr.Set("Location", "/login.html")
+	respHdr.Set("Set-Cookie", c.String())
 	w.WriteHeader(http.StatusFound)
 }
 
@@ -504,101 +505,108 @@ func RegisterAuthHandlers() {
 	httpRegister(http.MethodGet, "/control/logout", handleLogout)
 }
 
-func parseCookie(cookie string) string {
-	pairs := strings.Split(cookie, ";")
-	for _, pair := range pairs {
-		pair = strings.TrimSpace(pair)
-		kv := strings.SplitN(pair, "=", 2)
-		if len(kv) != 2 {
-			continue
-		}
-		if kv[0] == sessionCookieName {
-			return kv[1]
-		}
-	}
-	return ""
-}
-
 // optionalAuthThird return true if user should authenticate first.
-func optionalAuthThird(w http.ResponseWriter, r *http.Request) (authFirst bool) {
+func optionalAuthThird(w http.ResponseWriter, r *http.Request) (mustAuth bool) {
-	authFirst = false
+	if glProcessCookie(r) {
+		log.Debug("auth: authentication is handled by GL-Inet submodule")
+
+		return false
+	}
 
 	// redirect to login page if not authenticated
-	ok := false
+	isAuthenticated := false
 	cookie, err := r.Cookie(sessionCookieName)
-
+	if err != nil {
-	if glProcessCookie(r) {
+		// The only error that is returned from r.Cookie is [http.ErrNoCookie].
-		log.Debug("auth: authentication was handled by GL-Inet submodule")
+		// Check Basic authentication.
-		ok = true
+		user, pass, hasBasic := r.BasicAuth()
-	} else if err == nil {
+		if hasBasic {
-		r := Context.auth.checkSession(cookie.Value)
+			_, isAuthenticated = Context.auth.findUser(user, pass)
-		if r == checkSessionOK {
+			if !isAuthenticated {
-			ok = true
-		} else if r < 0 {
-			log.Debug("auth: invalid cookie value: %s", cookie)
-		}
-	} else {
-		// there's no Cookie, check Basic authentication
-		user, pass, ok2 := r.BasicAuth()
-		if ok2 {
-			u := Context.auth.UserFind(user, pass)
-			if len(u.Name) != 0 {
-				ok = true
-			} else {
 				log.Info("auth: invalid Basic Authorization value")
 			}
 		}
-	}
+	} else {
-	if !ok {
+		res := Context.auth.checkSession(cookie.Value)
-		if r.URL.Path == "/" || r.URL.Path == "/index.html" {
+		isAuthenticated = res == checkSessionOK
-			if glProcessRedirect(w, r) {
+		if !isAuthenticated {
-				log.Debug("auth: redirected to login page by GL-Inet submodule")
+			log.Debug("auth: invalid cookie value: %s", cookie)
-			} else {
-				w.Header().Set("Location", "/login.html")
-				w.WriteHeader(http.StatusFound)
-			}
-		} else {
-			w.WriteHeader(http.StatusForbidden)
-			_, _ = w.Write([]byte("Forbidden"))
 		}
-		authFirst = true
 	}
 
-	return authFirst
+	if isAuthenticated {
+		return false
+	}
+
+	if p := r.URL.Path; p == "/" || p == "/index.html" {
+		if glProcessRedirect(w, r) {
+			log.Debug("auth: redirected to login page by GL-Inet submodule")
+		} else {
+			log.Debug("auth: redirected to login page")
+			w.Header().Set("Location", "/login.html")
+			w.WriteHeader(http.StatusFound)
+		}
+	} else {
+		log.Debug("auth: responded with forbidden to %s %s", r.Method, p)
+		w.WriteHeader(http.StatusForbidden)
+		_, _ = w.Write([]byte("Forbidden"))
+	}
+
+	return true
 }
 
-func optionalAuth(handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) {
+// TODO(a.garipov): Use [http.Handler] consistently everywhere throughout the
+// project.
+func optionalAuth(
+	h func(http.ResponseWriter, *http.Request),
+) (wrapped func(http.ResponseWriter, *http.Request)) {
 	return func(w http.ResponseWriter, r *http.Request) {
-		if r.URL.Path == "/login.html" {
+		p := r.URL.Path
-			// redirect to dashboard if already authenticated
+		authRequired := Context.auth != nil && Context.auth.AuthRequired()
-			authRequired := Context.auth != nil && Context.auth.AuthRequired()
+		if p == "/login.html" {
 			cookie, err := r.Cookie(sessionCookieName)
 			if authRequired && err == nil {
-				r := Context.auth.checkSession(cookie.Value)
+				// Redirect to the dashboard if already authenticated.
-				if r == checkSessionOK {
+				res := Context.auth.checkSession(cookie.Value)
+				if res == checkSessionOK {
 					w.Header().Set("Location", "/")
 					w.WriteHeader(http.StatusFound)
 
 					return
-				} else if r == checkSessionNotFound {
-					log.Debug("auth: invalid cookie value: %s", cookie)
 				}
-			}
 
-		} else if strings.HasPrefix(r.URL.Path, "/assets/") ||
+				log.Debug("auth: invalid cookie value: %s", cookie)
-			strings.HasPrefix(r.URL.Path, "/login.") {
+			}
-			// process as usual
+		} else if isPublicResource(p) {
-			// no additional auth requirements
+			// Process as usual, no additional auth requirements.
-		} else if Context.auth != nil && Context.auth.AuthRequired() {
+		} else if authRequired {
 			if optionalAuthThird(w, r) {
 				return
 			}
 		}
 
-		handler(w, r)
+		h(w, r)
 	}
 }
 
+// isPublicResource returns true if p is a path to a public resource.
+func isPublicResource(p string) (ok bool) {
+	isAsset, err := path.Match("/assets/*", p)
+	if err != nil {
+		// The only error that is returned from path.Match is
+		// [path.ErrBadPattern].  This is a programmer error.
+		panic(fmt.Errorf("bad asset pattern: %w", err))
+	}
+
+	isLogin, err := path.Match("/login.*", p)
+	if err != nil {
+		// Same as above.
+		panic(fmt.Errorf("bad login pattern: %w", err))
+	}
+
+	return isAsset || isLogin
+}
+
 type authHandler struct {
 	handler http.Handler
 }
@@ -612,7 +620,7 @@ func optionalAuthHandler(handler http.Handler) http.Handler {
 }
 
 // UserAdd - add new user
-func (a *Auth) UserAdd(u *User, password string) {
+func (a *Auth) UserAdd(u *webUser, password string) {
 	if len(password) == 0 {
 		return
 	}
@@ -631,31 +639,35 @@ func (a *Auth) UserAdd(u *User, password string) {
 	log.Debug("auth: added user: %s", u.Name)
 }
 
-// UserFind - find a user
+// findUser returns a user if there is one.
-func (a *Auth) UserFind(login, password string) User {
+func (a *Auth) findUser(login, password string) (u webUser, ok bool) {
 	a.lock.Lock()
 	defer a.lock.Unlock()
-	for _, u := range a.users {
+
+	for _, u = range a.users {
 		if u.Name == login &&
 			bcrypt.CompareHashAndPassword([]byte(u.PasswordHash), []byte(password)) == nil {
-			return u
+			return u, true
 		}
 	}
-	return User{}
+
+	return webUser{}, false
 }
 
 // getCurrentUser returns the current user.  It returns an empty User if the
 // user is not found.
-func (a *Auth) getCurrentUser(r *http.Request) User {
+func (a *Auth) getCurrentUser(r *http.Request) (u webUser) {
 	cookie, err := r.Cookie(sessionCookieName)
 	if err != nil {
 		// There's no Cookie, check Basic authentication.
 		user, pass, ok := r.BasicAuth()
 		if ok {
-			return Context.auth.UserFind(user, pass)
+			u, _ = Context.auth.findUser(user, pass)
+
+			return u
 		}
 
-		return User{}
+		return webUser{}
 	}
 
 	a.lock.Lock()
@@ -663,20 +675,20 @@ func (a *Auth) getCurrentUser(r *http.Request) User {
 
 	s, ok := a.sessions[cookie.Value]
 	if !ok {
-		return User{}
+		return webUser{}
 	}
 
-	for _, u := range a.users {
+	for _, u = range a.users {
 		if u.Name == s.userName {
 			return u
 		}
 	}
 
-	return User{}
+	return webUser{}
 }
 
 // GetUsers - get users
-func (a *Auth) GetUsers() []User {
+func (a *Auth) GetUsers() []webUser {
 	a.lock.Lock()
 	users := a.users
 	a.lock.Unlock()

internal/home/auth_test.go

@@ -43,14 +43,14 @@ func TestAuth(t *testing.T) {
 	dir := t.TempDir()
 	fn := filepath.Join(dir, "sessions.db")
 
-	users := []User{{
+	users := []webUser{{
 		Name:         "name",
 		PasswordHash: "$2y$05$..vyzAECIhJPfaQiOK17IukcQnqEgKJHy0iETyYqxn3YXJl8yZuo2",
 	}}
 	a := InitAuth(fn, nil, 60, nil)
 	s := session{}
 
-	user := User{Name: "name"}
+	user := webUser{Name: "name"}
 	a.UserAdd(&user, "password")
 
 	assert.Equal(t, checkSessionNotFound, a.checkSession("notfound"))
@@ -84,7 +84,8 @@ func TestAuth(t *testing.T) {
 	a.storeSession(sess, &s)
 	a.Close()
 
-	u := a.UserFind("name", "password")
+	u, ok := a.findUser("name", "password")
+	assert.True(t, ok)
 	assert.NotEmpty(t, u.Name)
 
 	time.Sleep(3 * time.Second)
@@ -118,7 +119,7 @@ func TestAuthHTTP(t *testing.T) {
 	dir := t.TempDir()
 	fn := filepath.Join(dir, "sessions.db")
 
-	users := []User{
+	users := []webUser{
 		{Name: "name", PasswordHash: "$2y$05$..vyzAECIhJPfaQiOK17IukcQnqEgKJHy0iETyYqxn3YXJl8yZuo2"},
 	}
 	Context.auth = InitAuth(fn, users, 60, nil)
@@ -150,18 +151,19 @@ func TestAuthHTTP(t *testing.T) {
 	assert.True(t, handlerCalled)
 
 	// perform login
-	cookie, err := Context.auth.httpCookie(loginJSON{Name: "name", Password: "password"}, "")
+	cookie, err := Context.auth.newCookie(loginJSON{Name: "name", Password: "password"}, "")
 	require.NoError(t, err)
-	assert.NotEmpty(t, cookie)
+	require.NotNil(t, cookie)
 
 	// get /
 	handler2 = optionalAuth(handler)
 	w.hdr = make(http.Header)
-	r.Header.Set("Cookie", cookie)
+	r.Header.Set("Cookie", cookie.String())
 	r.URL = &url.URL{Path: "/"}
 	handlerCalled = false
 	handler2(&w, &r)
 	assert.True(t, handlerCalled)
+
 	r.Header.Del("Cookie")
 
 	// get / with basic auth
@@ -177,7 +179,7 @@ func TestAuthHTTP(t *testing.T) {
 	// get login page with a valid cookie - we're redirected to /
 	handler2 = optionalAuth(handler)
 	w.hdr = make(http.Header)
-	r.Header.Set("Cookie", cookie)
+	r.Header.Set("Cookie", cookie.String())
 	r.URL = &url.URL{Path: loginURL}
 	handlerCalled = false
 	handler2(&w, &r)

internal/home/clientshttp.go

@@ -93,13 +93,7 @@ func (clients *clientsContainer) handleGetClients(w http.ResponseWriter, r *http
 
 	data.Tags = clientTags
 
-	w.Header().Set("Content-Type", "application/json")
+	_ = aghhttp.WriteJSONResponse(w, r, data)
-	e := json.NewEncoder(w).Encode(data)
-	if e != nil {
-		aghhttp.Error(r, w, http.StatusInternalServerError, "failed to encode to json: %v", e)
-
-		return
-	}
 }
 
 // Convert JSON object to Client object
@@ -249,11 +243,7 @@ func (clients *clientsContainer) handleFindClient(w http.ResponseWriter, r *http
 		})
 	}
 
-	w.Header().Set("Content-Type", "application/json")
+	_ = aghhttp.WriteJSONResponse(w, r, data)
-	err := json.NewEncoder(w).Encode(data)
-	if err != nil {
-		aghhttp.Error(r, w, http.StatusInternalServerError, "Couldn't write response: %s", err)
-	}
 }
 
 // findRuntime looks up the IP in runtime and temporary storages, like

internal/home/config.go

@@ -3,7 +3,7 @@ package home
 import (
 	"bytes"
 	"fmt"
-	"net/netip"
+	"net"
 	"os"
 	"path/filepath"
 	"sync"
@@ -85,10 +85,10 @@ type configuration struct {
 	// It's reset after config is parsed
 	fileData []byte
 
-	BindHost     netip.Addr `yaml:"bind_host"`      // BindHost is the IP address of the HTTP server to bind to
+	BindHost     net.IP    `yaml:"bind_host"`      // BindHost is the IP address of the HTTP server to bind to
-	BindPort     int        `yaml:"bind_port"`      // BindPort is the port the HTTP server
+	BindPort     int       `yaml:"bind_port"`      // BindPort is the port the HTTP server
-	BetaBindPort int        `yaml:"beta_bind_port"` // BetaBindPort is the port for new client
+	BetaBindPort int       `yaml:"beta_bind_port"` // BetaBindPort is the port for new client
-	Users        []User     `yaml:"users"`          // Users that can access HTTP server
+	Users        []webUser `yaml:"users"`          // Users that can access HTTP server
 	// AuthAttempts is the maximum number of failed login attempts a user
 	// can do before being blocked.
 	AuthAttempts uint `yaml:"auth_attempts"`
@@ -135,8 +135,8 @@ type configuration struct {
 
 // field ordering is important -- yaml fields will mirror ordering from here
 type dnsConfig struct {
-	BindHosts []netip.Addr `yaml:"bind_hosts"`
+	BindHosts []net.IP `yaml:"bind_hosts"`
-	Port      int          `yaml:"port"`
+	Port      int      `yaml:"port"`
 
 	// time interval for statistics (in days)
 	StatsInterval uint32 `yaml:"statistics_interval"`
@@ -198,12 +198,12 @@ type tlsConfigSettings struct {
 var config = &configuration{
 	BindPort:           3000,
 	BetaBindPort:       0,
-	BindHost:           netip.IPv4Unspecified(),
+	BindHost:           net.IP{0, 0, 0, 0},
 	AuthAttempts:       5,
 	AuthBlockMin:       15,
 	WebSessionTTLHours: 30 * 24,
 	DNS: dnsConfig{
-		BindHosts:           []netip.Addr{netip.IPv4Unspecified()},
+		BindHosts:           []net.IP{{0, 0, 0, 0}},
 		Port:                defaultPortDNS,
 		StatsInterval:       1,
 		QueryLogEnabled:     true,

internal/home/control.go

@@ -3,11 +3,12 @@ package home
 import (
 	"encoding/json"
 	"fmt"
+	"net"
 	"net/http"
-	"net/netip"
 	"net/url"
 	"runtime"
 	"strings"
+	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
@@ -20,11 +21,11 @@ import (
 
 // appendDNSAddrs is a convenient helper for appending a formatted form of DNS
 // addresses to a slice of strings.
-func appendDNSAddrs(dst []string, addrs ...netip.Addr) (res []string) {
+func appendDNSAddrs(dst []string, addrs ...net.IP) (res []string) {
 	for _, addr := range addrs {
 		var hostport string
 		if config.DNS.Port != defaultPortDNS {
-			hostport = netip.AddrPortFrom(addr, uint16(config.DNS.Port)).String()
+			hostport = netutil.JoinHostPort(addr.String(), config.DNS.Port)
 		} else {
 			hostport = addr.String()
 		}
@@ -38,7 +39,7 @@ func appendDNSAddrs(dst []string, addrs ...netip.Addr) (res []string) {
 // appendDNSAddrsWithIfaces formats and appends all DNS addresses from src to
 // dst.  It also adds the IP addresses of all network interfaces if src contains
 // an unspecified IP address.
-func appendDNSAddrsWithIfaces(dst []string, src []netip.Addr) (res []string, err error) {
+func appendDNSAddrsWithIfaces(dst []string, src []net.IP) (res []string, err error) {
 	ifacesAdded := false
 	for _, h := range src {
 		if !h.IsUnspecified() {
@@ -71,9 +72,7 @@ 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, net.IP{127, 0, 0, 1})
-
-		addrs = appendDNSAddrs(addrs, addr)
 	} else {
 		addrs, err = appendDNSAddrsWithIfaces(addrs, hosts)
 		if err != nil {
@@ -99,16 +98,16 @@ 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"`
 	IsProtectionEnabled bool     `json:"protection_enabled"`
 	// TODO(e.burkov): Inspect if front-end doesn't requires this field as
 	// openapi.yaml declares.
-	IsDHCPAvailable bool   `json:"dhcp_available"`
+	IsDHCPAvailable bool `json:"dhcp_available"`
-	IsRunning       bool   `json:"running"`
+	IsRunning       bool `json:"running"`
-	Version         string `json:"version"`
-	Language        string `json:"language"`
 }
 
 func handleStatus(w http.ResponseWriter, r *http.Request) {
@@ -127,12 +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(),
 		}
 	}()
 
@@ -148,13 +147,7 @@ func handleStatus(w http.ResponseWriter, r *http.Request) {
 		resp.IsDHCPAvailable = Context.dhcpServer != nil
 	}
 
-	w.Header().Set("Content-Type", "application/json")
+	_ = aghhttp.WriteJSONResponse(w, r, resp)
-	err = json.NewEncoder(w).Encode(resp)
-	if err != nil {
-		aghhttp.Error(r, w, http.StatusInternalServerError, "Unable to write response json: %s", err)
-
-		return
-	}
 }
 
 type profileJSON struct {
@@ -164,13 +157,16 @@ type profileJSON struct {
 func handleGetProfile(w http.ResponseWriter, r *http.Request) {
 	pj := profileJSON{}
 	u := Context.auth.getCurrentUser(r)
+
 	pj.Name = u.Name
 
 	data, err := json.Marshal(pj)
 	if err != nil {
 		aghhttp.Error(r, w, http.StatusInternalServerError, "json.Marshal: %s", err)
+
 		return
 	}
+
 	_, _ = w.Write(data)
 }
 
@@ -201,19 +197,29 @@ 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 m != method {
+			aghhttp.Error(r, w, http.StatusMethodNotAllowed, "only method %s is allowed", method)
 
-		if r.Method != method {
-			http.Error(w, "This request must be "+method, http.StatusMethodNotAllowed)
 			return
 		}
 
-		if method == http.MethodPost || method == http.MethodPut || method == http.MethodDelete {
+		if modifiesData(m) {
+			if !ensureContentType(w, r) {
+				return
+			}
+
 			Context.controlLock.Lock()
 			defer Context.controlLock.Unlock()
 		}
@@ -222,6 +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/home/controlinstall.go

@@ -5,8 +5,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
-	"net/netip"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -59,25 +59,13 @@ func (web *Web) handleInstallGetAddresses(w http.ResponseWriter, r *http.Request
 		data.Interfaces[iface.Name] = iface
 	}
 
-	w.Header().Set("Content-Type", "application/json")
+	_ = aghhttp.WriteJSONResponse(w, r, data)
-	err = json.NewEncoder(w).Encode(data)
-	if err != nil {
-		aghhttp.Error(
-			r,
-			w,
-			http.StatusInternalServerError,
-			"Unable to marshal default addresses to json: %s",
-			err,
-		)
-
-		return
-	}
 }
 
 type checkConfReqEnt struct {
-	IP      netip.Addr `json:"ip"`
+	IP      net.IP `json:"ip"`
-	Port    int        `json:"port"`
+	Port    int    `json:"port"`
-	Autofix bool       `json:"autofix"`
+	Autofix bool   `json:"autofix"`
 }
 
 type checkConfReq struct {
@@ -128,7 +116,7 @@ func (req *checkConfReq) validateWeb(tcpPorts aghalg.UniqChecker[tcpPort]) (err
 		// unbound after install.
 	}
 
-	return aghnet.CheckPort("tcp", netip.AddrPortFrom(req.Web.IP, uint16(portInt)))
+	return aghnet.CheckPort("tcp", req.Web.IP, portInt)
 }
 
 // validateDNS returns error if the DNS part of the initial configuration can't
@@ -153,13 +141,13 @@ func (req *checkConfReq) validateDNS(
 			return false, err
 		}
 
-		err = aghnet.CheckPort("tcp", netip.AddrPortFrom(req.DNS.IP, uint16(port)))
+		err = aghnet.CheckPort("tcp", req.DNS.IP, port)
 		if err != nil {
 			return false, err
 		}
 	}
 
-	err = aghnet.CheckPort("udp", netip.AddrPortFrom(req.DNS.IP, uint16(port)))
+	err = aghnet.CheckPort("udp", req.DNS.IP, port)
 	if !aghnet.IsAddrInUse(err) {
 		return false, err
 	}
@@ -171,7 +159,7 @@ func (req *checkConfReq) validateDNS(
 			log.Error("disabling DNSStubListener: %s", err)
 		}
 
-		err = aghnet.CheckPort("udp", netip.AddrPortFrom(req.DNS.IP, uint16(port)))
+		err = aghnet.CheckPort("udp", req.DNS.IP, port)
 		canAutofix = false
 	}
 
@@ -201,19 +189,13 @@ func (web *Web) handleInstallCheckConfig(w http.ResponseWriter, r *http.Request)
 		resp.StaticIP = handleStaticIP(req.DNS.IP, req.SetStaticIP)
 	}
 
-	w.Header().Set("Content-Type", "application/json")
+	_ = aghhttp.WriteJSONResponse(w, r, resp)
-	err = json.NewEncoder(w).Encode(resp)
-	if err != nil {
-		aghhttp.Error(r, w, http.StatusInternalServerError, "encoding the response: %s", err)
-
-		return
-	}
 }
 
 // handleStaticIP - handles static IP request
 // It either checks if we have a static IP
 // Or if set=true, it tries to set it
-func handleStaticIP(ip netip.Addr, set bool) staticIPJSON {
+func handleStaticIP(ip net.IP, set bool) staticIPJSON {
 	resp := staticIPJSON{}
 
 	interfaceName := aghnet.InterfaceByIP(ip)
@@ -321,8 +303,8 @@ func disableDNSStubListener() error {
 }
 
 type applyConfigReqEnt struct {
-	IP   netip.Addr `json:"ip"`
+	IP   net.IP `json:"ip"`
-	Port int        `json:"port"`
+	Port int    `json:"port"`
 }
 
 type applyConfigReq struct {
@@ -388,14 +370,14 @@ func (web *Web) handleInstallConfigure(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	err = aghnet.CheckPort("udp", netip.AddrPortFrom(req.DNS.IP, uint16(req.DNS.Port)))
+	err = aghnet.CheckPort("udp", req.DNS.IP, req.DNS.Port)
 	if err != nil {
 		aghhttp.Error(r, w, http.StatusBadRequest, "%s", err)
 
 		return
 	}
 
-	err = aghnet.CheckPort("tcp", netip.AddrPortFrom(req.DNS.IP, uint16(req.DNS.Port)))
+	err = aghnet.CheckPort("tcp", req.DNS.IP, req.DNS.Port)
 	if err != nil {
 		aghhttp.Error(r, w, http.StatusBadRequest, "%s", err)
 
@@ -408,7 +390,7 @@ func (web *Web) handleInstallConfigure(w http.ResponseWriter, r *http.Request) {
 	Context.firstRun = false
 	config.BindHost = req.Web.IP
 	config.BindPort = req.Web.Port
-	config.DNS.BindHosts = []netip.Addr{req.DNS.IP}
+	config.DNS.BindHosts = []net.IP{req.DNS.IP}
 	config.DNS.Port = req.DNS.Port
 
 	// TODO(e.burkov): StartMods() should be put in a separate goroutine at the
@@ -424,7 +406,7 @@ func (web *Web) handleInstallConfigure(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	u := &User{
+	u := &webUser{
 		Name: req.Username,
 	}
 	Context.auth.UserAdd(u, req.Password)
@@ -481,9 +463,9 @@ func decodeApplyConfigReq(r io.Reader) (req *applyConfigReq, restartHTTP bool, e
 		return nil, false, errors.Error("ports cannot be 0")
 	}
 
-	restartHTTP = config.BindHost != req.Web.IP || config.BindPort != req.Web.Port
+	restartHTTP = !config.BindHost.Equal(req.Web.IP) || config.BindPort != req.Web.Port
 	if restartHTTP {
-		err = aghnet.CheckPort("tcp", netip.AddrPortFrom(req.Web.IP, uint16(req.Web.Port)))
+		err = aghnet.CheckPort("tcp", req.Web.IP, req.Web.Port)
 		if err != nil {
 			return nil, false, fmt.Errorf(
 				"checking address %s:%d: %w",
@@ -509,9 +491,9 @@ func (web *Web) registerInstallHandlers() {
 // TODO(e.burkov): This should removed with the API v1 when the appropriate
 // functionality will appear in default checkConfigReqEnt.
 type checkConfigReqEntBeta struct {
-	IP      []netip.Addr `json:"ip"`
+	IP      []net.IP `json:"ip"`
-	Port    int          `json:"port"`
+	Port    int      `json:"port"`
-	Autofix bool         `json:"autofix"`
+	Autofix bool     `json:"autofix"`
 }
 
 // checkConfigReqBeta is a struct representing new client's config check request
@@ -586,8 +568,8 @@ func (web *Web) handleInstallCheckConfigBeta(w http.ResponseWriter, r *http.Requ
 // TODO(e.burkov): This should removed with the API v1 when the appropriate
 // functionality will appear in default applyConfigReqEnt.
 type applyConfigReqEntBeta struct {
-	IP   []netip.Addr `json:"ip"`
+	IP   []net.IP `json:"ip"`
-	Port int          `json:"port"`
+	Port int      `json:"port"`
 }
 
 // applyConfigReqBeta is a struct representing new client's config setting
@@ -688,19 +670,7 @@ func (web *Web) handleInstallGetAddressesBeta(w http.ResponseWriter, r *http.Req
 
 	data.Interfaces = ifaces
 
-	w.Header().Set("Content-Type", "application/json")
+	_ = aghhttp.WriteJSONResponse(w, r, data)
-	err = json.NewEncoder(w).Encode(data)
-	if err != nil {
-		aghhttp.Error(
-			r,
-			w,
-			http.StatusInternalServerError,
-			"Unable to marshal default addresses to json: %s",
-			err,
-		)
-
-		return
-	}
 }
 
 // registerBetaInstallHandlers registers the install handlers for new client

internal/home/controlupdate.go

@@ -28,8 +28,6 @@ type temporaryError interface {
 
 // Get the latest available version from the Internet
 func handleGetVersionJSON(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Content-Type", "application/json")
-
 	resp := &versionResponse{}
 	if Context.disableUpdate {
 		resp.Disabled = true
@@ -71,10 +69,7 @@ func handleGetVersionJSON(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	err = json.NewEncoder(w).Encode(resp)
+	_ = aghhttp.WriteJSONResponse(w, r, resp)
-	if err != nil {
-		aghhttp.Error(r, w, http.StatusInternalServerError, "writing body: %s", err)
-	}
 }
 
 // requestVersionInfo sets the VersionInfo field of resp if it can reach the

internal/home/dns.go

@@ -3,7 +3,6 @@ package home
 import (
 	"fmt"
 	"net"
-	"net/netip"
 	"net/url"
 	"os"
 	"path/filepath"
@@ -165,27 +164,33 @@ func onDNSRequest(pctx *proxy.DNSContext) {
 	}
 }
 
-func ipsToTCPAddrs(ips []netip.Addr, port int) (tcpAddrs []*net.TCPAddr) {
+func ipsToTCPAddrs(ips []net.IP, port int) (tcpAddrs []*net.TCPAddr) {
 	if ips == nil {
 		return nil
 	}
 
-	tcpAddrs = make([]*net.TCPAddr, 0, len(ips))
+	tcpAddrs = make([]*net.TCPAddr, len(ips))
-	for _, ip := range ips {
+	for i, ip := range ips {
-		tcpAddrs = append(tcpAddrs, net.TCPAddrFromAddrPort(netip.AddrPortFrom(ip, uint16(port))))
+		tcpAddrs[i] = &net.TCPAddr{
+			IP:   ip,
+			Port: port,
+		}
 	}
 
 	return tcpAddrs
 }
 
-func ipsToUDPAddrs(ips []netip.Addr, port int) (udpAddrs []*net.UDPAddr) {
+func ipsToUDPAddrs(ips []net.IP, port int) (udpAddrs []*net.UDPAddr) {
 	if ips == nil {
 		return nil
 	}
 
-	udpAddrs = make([]*net.UDPAddr, 0, len(ips))
+	udpAddrs = make([]*net.UDPAddr, len(ips))
-	for _, ip := range ips {
+	for i, ip := range ips {
-		udpAddrs = append(udpAddrs, net.UDPAddrFromAddrPort(netip.AddrPortFrom(ip, uint16(port))))
+		udpAddrs[i] = &net.UDPAddr{
+			IP:   ip,
+			Port: port,
+		}
 	}
 
 	return udpAddrs
@@ -195,7 +200,7 @@ func generateServerConfig() (newConf dnsforward.ServerConfig, err error) {
 	dnsConf := config.DNS
 	hosts := dnsConf.BindHosts
 	if len(hosts) == 0 {
-		hosts = []netip.Addr{aghnet.IPv4Localhost()}
+		hosts = []net.IP{{127, 0, 0, 1}}
 	}
 
 	newConf = dnsforward.ServerConfig{
@@ -249,7 +254,7 @@ 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 []net.IP, tlsConf tlsConfigSettings) (dnscc dnsforward.DNSCryptConfig, err error) {
 	if tlsConf.DNSCryptConfigFile == "" {
 		return dnscc, errors.Error("no dnscrypt_config_file")
 	}

internal/home/home.go

@@ -10,7 +10,6 @@ import (
 	"net"
 	"net/http"
 	"net/http/pprof"
-	"net/netip"
 	"net/url"
 	"os"
 	"os/signal"
@@ -278,6 +277,7 @@ func setupConfig(args options) (err error) {
 	config.DNS.DnsfilterConf.DataDir = Context.getDataDir()
 	config.DNS.DnsfilterConf.Filters = slices.Clone(config.Filters)
 	config.DNS.DnsfilterConf.WhitelistFilters = slices.Clone(config.WhitelistFilters)
+	config.DNS.DnsfilterConf.UserRules = slices.Clone(config.UserRules)
 	config.DNS.DnsfilterConf.HTTPClient = Context.client
 
 	config.DHCP.WorkDir = Context.workDir
@@ -340,7 +340,7 @@ func setupConfig(args options) (err error) {
 	}
 
 	// override bind host/port from the console
-	if args.bindHost.IsValid() {
+	if args.bindHost != nil {
 		config.BindHost = args.bindHost
 	}
 	if len(args.pidFile) != 0 && writePIDFile(args.pidFile) {
@@ -409,7 +409,7 @@ func run(args options, clientBuildFS fs.FS) {
 	configureLogger(args)
 
 	// Print the first message after logger is configured.
-	log.Println(version.Full())
+	log.Info(version.Full())
 	log.Debug("current working directory is %s", Context.workDir)
 	if args.runningAsService {
 		log.Info("AdGuard Home is running as a service")
@@ -455,9 +455,9 @@ func run(args options, clientBuildFS fs.FS) {
 
 	sessFilename := filepath.Join(Context.getDataDir(), "sessions.db")
 	GLMode = args.glinetMode
-	var arl *authRateLimiter
+	var rateLimiter *authRateLimiter
 	if config.AuthAttempts > 0 && config.AuthBlockMin > 0 {
-		arl = newAuthRateLimiter(
+		rateLimiter = newAuthRateLimiter(
 			time.Duration(config.AuthBlockMin)*time.Minute,
 			config.AuthAttempts,
 		)
@@ -469,7 +469,7 @@ func run(args options, clientBuildFS fs.FS) {
 		sessFilename,
 		config.Users,
 		config.WebSessionTTLHours*60*60,
-		arl,
+		rateLimiter,
 	)
 	if Context.auth == nil {
 		log.Fatalf("Couldn't initialize Auth module")
@@ -538,7 +538,7 @@ 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", net.IP{127, 0, 0, 1}, defaultPortDNS)
 	if err != nil {
 		if errors.Is(err, os.ErrPermission) {
 			log.Fatal(`Permission check failed.

internal/home/i18n.go

@@ -1,10 +1,8 @@
 package home
 
 import (
-	"fmt"
+	"encoding/json"
-	"io"
 	"net/http"
-	"strings"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
 	"github.com/AdguardTeam/golibs/log"
@@ -51,43 +49,35 @@ var allowedLanguages = stringutil.NewSet(
 	"zh-tw",
 )
 
-func handleI18nCurrentLanguage(w http.ResponseWriter, _ *http.Request) {
+// languageJSON is the JSON structure for language requests and responses.
-	w.Header().Set("Content-Type", "text/plain")
+type languageJSON struct {
-	log.Printf("config.Language is %s", config.Language)
+	Language string `json:"language"`
-	_, err := fmt.Fprintf(w, "%s\n", config.Language)
+}
-	if err != nil {
-		msg := fmt.Sprintf("Unable to write response json: %s", err)
-		log.Println(msg)
-		http.Error(w, msg, http.StatusInternalServerError)
 
-		return
+func handleI18nCurrentLanguage(w http.ResponseWriter, r *http.Request) {
-	}
+	log.Printf("home: language is %s", config.Language)
+
+	_ = aghhttp.WriteJSONResponse(w, r, &languageJSON{
+		Language: config.Language,
+	})
 }
 
 func handleI18nChangeLanguage(w http.ResponseWriter, r *http.Request) {
-	// This use of ReadAll is safe, because request's body is now limited.
+	if aghhttp.WriteTextPlainDeprecated(w, r) {
-	body, err := io.ReadAll(r.Body)
+		return
+	}
+
+	langReq := &languageJSON{}
+	err := json.NewDecoder(r.Body).Decode(langReq)
 	if err != nil {
-		msg := fmt.Sprintf("failed to read request body: %s", err)
+		aghhttp.Error(r, w, http.StatusInternalServerError, "reading req: %s", err)
-		log.Println(msg)
-		http.Error(w, msg, http.StatusBadRequest)
 
 		return
 	}
 
-	language := strings.TrimSpace(string(body))
+	lang := langReq.Language
-	if language == "" {
+	if !allowedLanguages.Has(lang) {
-		msg := "empty language specified"
+		aghhttp.Error(r, w, http.StatusBadRequest, "unknown language: %q", lang)
-		log.Println(msg)
-		http.Error(w, msg, http.StatusBadRequest)
-
-		return
-	}
-
-	if !allowedLanguages.Has(language) {
-		msg := fmt.Sprintf("unknown language specified: %s", language)
-		log.Println(msg)
-		http.Error(w, msg, http.StatusBadRequest)
 
 		return
 	}
@@ -96,7 +86,8 @@ func handleI18nChangeLanguage(w http.ResponseWriter, r *http.Request) {
 		config.Lock()
 		defer config.Unlock()
 
-		config.Language = language
+		config.Language = lang
+		log.Printf("home: language is set to %s", lang)
 	}()
 
 	onConfigModified()

internal/home/mobileconfig_test.go

@@ -3,11 +3,12 @@ package home
 import (
 	"bytes"
 	"encoding/json"
+	"net"
 	"net/http"
 	"net/http/httptest"
-	"net/netip"
 	"testing"
 
+	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"howett.net/plist"
@@ -27,7 +28,7 @@ func setupDNSIPs(t testing.TB) {
 
 	config = &configuration{
 		DNS: dnsConfig{
-			BindHosts: []netip.Addr{netip.IPv4Unspecified()},
+			BindHosts: []net.IP{netutil.IPv4Zero()},
 			Port:      defaultPortDNS,
 		},
 	}

internal/home/options.go

@@ -2,7 +2,7 @@ package home
 
 import (
 	"fmt"
-	"net/netip"
+	"net"
 	"os"
 	"strconv"
 
@@ -12,15 +12,15 @@ import (
 
 // options passed from command-line arguments
 type options struct {
-	verbose        bool       // is verbose logging enabled
+	verbose        bool   // is verbose logging enabled
-	configFilename string     // path to the config file
+	configFilename string // path to the config file
-	workDir        string     // path to the working directory where we will store the filters data and the querylog
+	workDir        string // path to the working directory where we will store the filters data and the querylog
-	bindHost       netip.Addr // host address to bind HTTP server on
+	bindHost       net.IP // host address to bind HTTP server on
-	bindPort       int        // port to serve HTTP pages on
+	bindPort       int    // port to serve HTTP pages on
-	logFile        string     // Path to the log file. If empty, write to stdout. If "syslog", writes to syslog
+	logFile        string // Path to the log file. If empty, write to stdout. If "syslog", writes to syslog
-	pidFile        string     // File name to save PID to
+	pidFile        string // File name to save PID to
-	checkConfig    bool       // Check configuration and exit
+	checkConfig    bool   // Check configuration and exit
-	disableUpdate  bool       // If set, don't check for updates
+	disableUpdate  bool   // If set, don't check for updates
 
 	// service control action (see service.ControlAction array + "status" command)
 	serviceControlAction string
@@ -60,8 +60,8 @@ type arg struct {
 // against its zero value and return nil if the parameter value is
 // zero otherwise they return a string slice of the parameter
 
-func ipSliceOrNil(ip netip.Addr) []string {
+func ipSliceOrNil(ip net.IP) []string {
-	if !ip.IsValid() {
+	if ip == nil {
 		return nil
 	}
 
@@ -113,7 +113,7 @@ var workDirArg = arg{
 var hostArg = arg{
 	"Host address to bind HTTP server on.",
 	"host", "h",
-	func(o options, v string) (options, error) { o.bindHost, _ = netip.ParseAddr(v); return o, nil }, nil, nil,
+	func(o options, v string) (options, error) { o.bindHost = net.ParseIP(v); return o, nil }, nil, nil,
 	func(o options) []string { return ipSliceOrNil(o.bindHost) },
 }
 

internal/home/options_test.go

@@ -2,7 +2,7 @@ package home
 
 import (
 	"fmt"
-	"net/netip"
+	"net"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -56,13 +56,11 @@ func TestParseWorkDir(t *testing.T) {
 }
 
 func TestParseBindHost(t *testing.T) {
-	wantAddr := netip.AddrFrom4([4]byte{1, 2, 3, 4})
+	assert.Nil(t, testParseOK(t).bindHost, "empty is not host")
-
+	assert.Equal(t, net.IPv4(1, 2, 3, 4), testParseOK(t, "-h", "1.2.3.4").bindHost, "-h is host")
-	assert.Zero(t, testParseOK(t).bindHost, "empty is not host")
-	assert.Equal(t, wantAddr, testParseOK(t, "-h", "1.2.3.4").bindHost, "-h is host")
 	testParseParamMissing(t, "-h")
 
-	assert.Equal(t, wantAddr, testParseOK(t, "--host", "1.2.3.4").bindHost, "--host is host")
+	assert.Equal(t, net.IPv4(1, 2, 3, 4), testParseOK(t, "--host", "1.2.3.4").bindHost, "--host is host")
 	testParseParamMissing(t, "--host")
 }
 
@@ -151,7 +149,7 @@ func TestSerialize(t *testing.T) {
 		ss:   []string{"-w", "path"},
 	}, {
 		name: "bind_host",
-		opts: options{bindHost: netip.AddrFrom4([4]byte{1, 2, 3, 4})},
+		opts: options{bindHost: net.IP{1, 2, 3, 4}},
 		ss:   []string{"-h", "1.2.3.4"},
 	}, {
 		name: "bind_port",

internal/home/service.go

@@ -176,7 +176,8 @@ func handleServiceControlAction(opts options, clientBuildFS fs.FS) {
 	chooseSystem()
 
 	action := opts.serviceControlAction
-	log.Printf("service: control action: %s", action)
+	log.Info(version.Full())
+	log.Info("service: control action: %s", action)
 
 	if action == "reload" {
 		sendSigReload()

internal/home/tls.go

@@ -680,8 +680,6 @@ func unmarshalTLS(r *http.Request) (tlsConfigSettingsExt, error) {
 }
 
 func marshalTLS(w http.ResponseWriter, r *http.Request, data tlsConfig) {
-	w.Header().Set("Content-Type", "application/json")
-
 	if data.CertificateChain != "" {
 		encoded := base64.StdEncoding.EncodeToString([]byte(data.CertificateChain))
 		data.CertificateChain = encoded
@@ -692,16 +690,7 @@ func marshalTLS(w http.ResponseWriter, r *http.Request, data tlsConfig) {
 		data.PrivateKey = ""
 	}
 
-	err := json.NewEncoder(w).Encode(data)
+	_ = aghhttp.WriteJSONResponse(w, r, data)
-	if err != nil {
-		aghhttp.Error(
-			r,
-			w,
-			http.StatusInternalServerError,
-			"Failed to marshal json with TLS status: %s",
-			err,
-		)
-	}
 }
 
 // registerWebHandlers registers HTTP handlers for TLS configuration

internal/home/upgrade.go

@@ -278,11 +278,11 @@ func upgradeSchema4to5(diskConf yobj) error {
 		log.Fatalf("Can't use password \"%s\": bcrypt.GenerateFromPassword: %s", passStr, err)
 		return nil
 	}
-	u := User{
+	u := webUser{
 		Name:         nameStr,
 		PasswordHash: string(hash),
 	}
-	users := []User{u}
+	users := []webUser{u}
 	diskConf["users"] = users
 	return nil
 }

internal/home/web.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"crypto/tls"
 	"io/fs"
+	"net"
 	"net/http"
-	"net/netip"
 	"sync"
 	"time"
 
@@ -35,7 +35,7 @@ type webConfig struct {
 	clientFS     fs.FS
 	clientBetaFS fs.FS
 
-	BindHost     netip.Addr
+	BindHost     net.IP
 	BindPort     int
 	BetaBindPort int
 	PortHTTPS    int
@@ -114,11 +114,8 @@ func CreateWeb(conf *webConfig) *Web {
 // WebCheckPortAvailable - check if port is available
 // BUT: if we are already using this port, no need
 func WebCheckPortAvailable(port int) bool {
-	if Context.web.httpsServer.server != nil {
+	return Context.web.httpsServer.server != nil ||
-		return true
+		aghnet.CheckPort("tcp", config.BindHost, port) == nil
-	}
-
-	return aghnet.CheckPort("tcp", netip.AddrPortFrom(config.BindHost, uint16(port))) == nil
 }
 
 // TLSConfigChanged updates the TLS configuration and restarts the HTTPS server

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{
-		Addresses: []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:3001")},
+		// TODO(a.garipov): Use an actual implementation.
-		Start:     start,
+		ConfigManager: nil,
-		Timeout:   60 * time.Second,
+		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()
 }
 
@@ -173,13 +193,27 @@ 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?
-	udpAddrs := svc.proxy.Addrs(proxy.ProtoUDP)
+
-	addrs := make([]netip.AddrPort, len(udpAddrs))
+	var addrs []netip.AddrPort
-	for i, a := range udpAddrs {
+	if atomic.LoadUint64(&svc.running) == 1 {
-		addrs[i] = a.(*net.UDPAddr).AddrPort()
+		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{

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 {
-	tls     *tls.Config
+	confMgr    ConfigManager
-	servers []*http.Server
+	tls        *tls.Config
-	start   time.Time
+	start      time.Time
-	timeout time.Duration
+	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{
-		tls:     c.TLS,
+		confMgr:    c.ConfigManager,
-		start:   c.Start,
+		tls:        c.TLS,
-		timeout: c.Timeout,
+		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))
+		}
+
+		// 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
+	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

@@ -4,6 +4,89 @@
 
 ## v0.108.0: API changes
 
+
+
+## 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
+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`.
+
+### `POST /control/filtering/set_rules` And Other Plain-Text APIs
+
+The following APIs, which previously accepted or returned `text/plain` data,
+now accept or return data as JSON.
+
+#### `POST /control/filtering/set_rules`
+
+Previously, the API accepted a raw list of filters as a plain-text file.  Now,
+the filters must be presented in a JSON object with the following format:
+
+```json
+{
+  "rules":
+  [
+    "||example.com^",
+    "# comment",
+    "@@||www.example.com^"
+  ]
+}
+```
+
+#### `GET /control/i18n/current_language` And `POST /control/i18n/change_language`
+
+Previously, these APIs accepted and returned the language code in plain text.
+Now, they accept and return them in a JSON object with the following format:
+
+```json
+{
+  "language": "en"
+}
+```
+
+#### `POST /control/dhcp/find_active_dhcp`
+
+Previously, the API accepted the name of the network interface as a plain-text
+string.  Now, it must be contained within a JSON object with the following
+format:
+
+```json
+{
+  "interface": "eth0"
+}
+```
+
+
+
 ## v0.107.12: API changes
 
 ### `GET /control/blocked_services/services`
@@ -11,6 +94,8 @@
 * The new `GET /control/blocked_services/services` HTTP API allows inspecting
   all available services.
 
+
+
 ## v0.107.7: API changes
 
 ### The new optional field `"ecs"` in `QueryLogItem`
@@ -24,6 +109,8 @@
   `POST /install/configure` which means that the specified password does not
   meet the strength requirements.
 
+
+
 ## v0.107.3: API changes
 
 ### The new field `"version"` in `AddressesInfo`
@@ -31,6 +118,8 @@
 * The new field `"version"` in `GET /install/get_addresses` is the version of
   the AdGuard Home instance.
 
+
+
 ## v0.107.0: API changes
 
 ### The new field `"cached"` in `QueryLogItem`

openapi/openapi.yaml

@@ -413,6 +413,11 @@
       - 'dhcp'
       'operationId': 'checkActiveDhcp'
       'summary': 'Searches for an active DHCP server on the network'
+      'requestBody':
+        'content':
+          'application/json':
+            'schema':
+              '$ref': '#/components/schemas/DhcpFindActiveReq'
       'responses':
         '200':
           'description': 'OK.'
@@ -596,11 +601,10 @@
       'summary': 'Set user-defined filter rules'
       'requestBody':
         'content':
-          'text/plain':
+          'application/json':
             'schema':
-              'type': 'string'
+              '$ref': '#/components/schemas/SetRulesRequest'
-              'example': '@@||yandex.ru^|'
+        'description': 'Custom filtering rules.'
-        'description': 'All filtering rules, one line per rule'
       'responses':
         '200':
           'description': 'OK.'
@@ -667,24 +671,6 @@
       - 'parental'
       'operationId': 'parentalEnable'
       'summary': 'Enable parental filtering'
-      'requestBody':
-        'content':
-          'text/plain':
-            'schema':
-              'type': 'string'
-              'enum':
-              - 'EARLY_CHILDHOOD'
-              - 'YOUNG'
-              - 'TEEN'
-              - 'MATURE'
-              'example': 'sensitivity=TEEN'
-        'description': |
-          Age sensitivity for parental filtering,
-          EARLY_CHILDHOOD is 3
-          YOUNG is 10
-          TEEN is 13
-          MATURE is 17
-        'required': true
       'responses':
         '200':
           'description': 'OK.'
@@ -958,10 +944,9 @@
         Change current language.  Argument must be an ISO 639-1 two-letter code.
       'requestBody':
         'content':
-          'text/plain':
+          'application/json':
             'schema':
-              'type': 'string'
+              '$ref': '#/components/schemas/LanguageSettings'
-              'example': 'en'
         'description': >
           New language.  It must be known to the server and must be an ISO 639-1
           two-letter code.
@@ -980,10 +965,9 @@
         '200':
           'description': 'OK.'
           'content':
-            'text/plain':
+            'application/json':
-              'examples':
+              'schema':
-                'response':
+                '$ref': '#/components/schemas/LanguageSettings'
-                  'value': 'en'
   '/install/get_addresses_beta':
     'get':
       'tags':
@@ -1553,6 +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'
@@ -1777,6 +1774,16 @@
       'additionalProperties':
         '$ref': '#/components/schemas/NetInterface'
 
+    'DhcpFindActiveReq':
+      'description': >
+        Request for checking for other DHCP servers in the network.
+      'properties':
+        'interface':
+          'description': 'The name of the network interface'
+          'example': 'eth0'
+          'type': 'string'
+      'type': 'object'
+
     'DhcpSearchResult':
       'type': 'object'
       'description': >
@@ -2692,6 +2699,15 @@
           'description': 'The error message, an opaque string.'
           'type': 'string'
       'type': 'object'
+    'LanguageSettings':
+      'description': 'Language settings object.'
+      'properties':
+        'language':
+          'description': 'The current language or the language to set.'
+          'type': 'string'
+      'required':
+      - 'language'
+      'type': 'object'
   'securitySchemes':
     'basicAuth':
       'type': 'http'

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 ./...