+ DNS: Get/Set DNS general settings

GET /control/dns_info
POST /control/dns_config

AGHTechDoc.md

@@ -29,6 +29,9 @@ Contents:
 	* Static IP check/set
 	* Add a static lease
 	* API: Reset DHCP configuration
+* DNS general settings
+	* API: Get DNS general settings
+	* API: Set DNS general settings
 * DNS access settings
 	* List access settings
 	* Set access settings
@@ -801,6 +804,42 @@ Response:
 	]
 
 
+## DNS general settings
+
+### API: Get DNS general settings
+
+Request:
+
+	GET /control/dns_info
+
+Response:
+
+	200 OK
+
+	{
+		"protection_enabled": true | false,
+		"ratelimit": 1234,
+		"blocking_mode": "nxdomain" | "null_ip",
+	}
+
+
+### API: Set DNS general settings
+
+Request:
+
+	POST /control/dns_config
+
+	{
+		"protection_enabled": true | false,
+		"ratelimit": 1234,
+		"blocking_mode": "nxdomain" | "null_ip",
+	}
+
+Response:
+
+	200 OK
+
+
 ## DNS access settings
 
 There are low-level settings that can block undesired DNS requests.  "Blocking" means not responding to request.

dnsforward/dnsforward.go

@@ -101,7 +101,7 @@ type FilteringConfig struct {
 
 	BlockingMode       string   `yaml:"blocking_mode"`        // mode how to answer filtered requests
 	BlockedResponseTTL uint32   `yaml:"blocked_response_ttl"` // if 0, then default is used (3600)
-	Ratelimit          int      `yaml:"ratelimit"`            // max number of requests per second from a given IP (0 to disable)
+	Ratelimit          uint32   `yaml:"ratelimit"`            // max number of requests per second from a given IP (0 to disable)
 	RatelimitWhitelist []string `yaml:"ratelimit_whitelist"`  // a list of whitelisted client IP addresses
 	RefuseAny          bool     `yaml:"refuse_any"`           // if true, refuse ANY requests
 	BootstrapDNS       []string `yaml:"bootstrap_dns"`        // a list of bootstrap DNS for DoH and DoT (plain DNS only)
@@ -214,7 +214,7 @@ func (s *Server) prepare(config *ServerConfig) error {
 	proxyConfig := proxy.Config{
 		UDPListenAddr:            s.conf.UDPListenAddr,
 		TCPListenAddr:            s.conf.TCPListenAddr,
-		Ratelimit:                s.conf.Ratelimit,
+		Ratelimit:                int(s.conf.Ratelimit),
 		RatelimitWhitelist:       s.conf.RatelimitWhitelist,
 		RefuseAny:                s.conf.RefuseAny,
 		CacheEnabled:             true,

dnsforward/dnsforward_http.go

@@ -20,6 +20,62 @@ func httpError(r *http.Request, w http.ResponseWriter, code int, format string,
 	http.Error(w, text, code)
 }
 
+type dnsConfigJSON struct {
+	ProtectionEnabled bool   `json:"protection_enabled"`
+	RateLimit         uint32 `json:"ratelimit"`
+	BlockingMode      string `json:"blocking_mode"`
+}
+
+func (s *Server) handleGetConfig(w http.ResponseWriter, r *http.Request) {
+	resp := dnsConfigJSON{}
+	s.RLock()
+	resp.ProtectionEnabled = s.conf.ProtectionEnabled
+	resp.BlockingMode = s.conf.BlockingMode
+	resp.RateLimit = s.conf.Ratelimit
+	s.RUnlock()
+
+	js, err := json.Marshal(resp)
+	if err != nil {
+		httpError(r, w, http.StatusInternalServerError, "json.Marshal: %s", err)
+		return
+	}
+	w.Header().Set("Content-Type", "application/json")
+	_, _ = w.Write(js)
+}
+
+func (s *Server) handleSetConfig(w http.ResponseWriter, r *http.Request) {
+	req := dnsConfigJSON{}
+	err := json.NewDecoder(r.Body).Decode(&req)
+	if err != nil {
+		httpError(r, w, http.StatusBadRequest, "json.Decode: %s", err)
+		return
+	}
+
+	if !(req.BlockingMode == "nxdomain" || req.BlockingMode == "null_ip") {
+		httpError(r, w, http.StatusBadRequest, "blocking_mode: value not supported")
+		return
+	}
+
+	restart := false
+	s.Lock()
+	s.conf.ProtectionEnabled = req.ProtectionEnabled
+	s.conf.BlockingMode = req.BlockingMode
+	if s.conf.Ratelimit != req.RateLimit {
+		restart = true
+	}
+	s.conf.Ratelimit = req.RateLimit
+	s.Unlock()
+	s.conf.ConfigModified()
+
+	if restart {
+		err = s.Restart()
+		if err != nil {
+			httpError(r, w, http.StatusInternalServerError, "%s", err)
+			return
+		}
+	}
+}
+
 func (s *Server) handleProtectionEnable(w http.ResponseWriter, r *http.Request) {
 	s.conf.ProtectionEnabled = true
 	s.conf.ConfigModified()
@@ -270,6 +326,8 @@ func checkDNS(input string, bootstrap []string) error {
 }
 
 func (s *Server) registerHandlers() {
+	s.conf.HTTPRegister("GET", "/control/dns_info", s.handleGetConfig)
+	s.conf.HTTPRegister("POST", "/control/dns_config", s.handleSetConfig)
 	s.conf.HTTPRegister("POST", "/control/enable_protection", s.handleProtectionEnable)
 	s.conf.HTTPRegister("POST", "/control/disable_protection", s.handleProtectionDisable)
 	s.conf.HTTPRegister("POST", "/control/set_upstreams_config", s.handleSetUpstreamConfig)
@@ -277,5 +335,4 @@ func (s *Server) registerHandlers() {
 
 	s.conf.HTTPRegister("GET", "/control/access/list", s.handleAccessList)
 	s.conf.HTTPRegister("POST", "/control/access/set", s.handleAccessSet)
-
 }