package home import ( "context" "encoding/json" "fmt" "io/ioutil" "net" "net/http" "os" "os/exec" "path/filepath" "runtime" "strconv" "github.com/AdguardTeam/AdGuardHome/internal/util" "github.com/AdguardTeam/AdGuardHome/internal/dhcpd" "github.com/AdguardTeam/golibs/log" ) type firstRunData struct { WebPort int `json:"web_port"` DNSPort int `json:"dns_port"` Interfaces map[string]interface{} `json:"interfaces"` } type netInterfaceJSON struct { Name string `json:"name"` MTU int `json:"mtu"` HardwareAddr string `json:"hardware_address"` Addresses []string `json:"ip_addresses"` Flags string `json:"flags"` } // Get initial installation settings func (web *Web) handleInstallGetAddresses(w http.ResponseWriter, r *http.Request) { data := firstRunData{} data.WebPort = 80 data.DNSPort = 53 ifaces, err := util.GetValidNetInterfacesForWeb() if err != nil { httpError(w, http.StatusInternalServerError, "Couldn't get interfaces: %s", err) return } data.Interfaces = make(map[string]interface{}) for _, iface := range ifaces { ifaceJSON := netInterfaceJSON{ Name: iface.Name, MTU: iface.MTU, HardwareAddr: iface.HardwareAddr, Addresses: iface.Addresses, Flags: iface.Flags, } data.Interfaces[iface.Name] = ifaceJSON } w.Header().Set("Content-Type", "application/json") err = json.NewEncoder(w).Encode(data) if err != nil { httpError(w, http.StatusInternalServerError, "Unable to marshal default addresses to json: %s", err) return } } type checkConfigReqEnt struct { Port int `json:"port"` IP string `json:"ip"` Autofix bool `json:"autofix"` } type checkConfigReq struct { Web checkConfigReqEnt `json:"web"` DNS checkConfigReqEnt `json:"dns"` SetStaticIP bool `json:"set_static_ip"` } type checkConfigRespEnt struct { Status string `json:"status"` CanAutofix bool `json:"can_autofix"` } type staticIPJSON struct { Static string `json:"static"` IP string `json:"ip"` Error string `json:"error"` } type checkConfigResp struct { Web checkConfigRespEnt `json:"web"` DNS checkConfigRespEnt `json:"dns"` StaticIP staticIPJSON `json:"static_ip"` } // Check if ports are available, respond with results func (web *Web) handleInstallCheckConfig(w http.ResponseWriter, r *http.Request) { reqData := checkConfigReq{} respData := checkConfigResp{} err := json.NewDecoder(r.Body).Decode(&reqData) if err != nil { httpError(w, http.StatusBadRequest, "Failed to parse 'check_config' JSON data: %s", err) return } if reqData.Web.Port != 0 && reqData.Web.Port != config.BindPort { err = util.CheckPortAvailable(reqData.Web.IP, reqData.Web.Port) if err != nil { respData.Web.Status = fmt.Sprintf("%v", err) } } if reqData.DNS.Port != 0 { err = util.CheckPacketPortAvailable(reqData.DNS.IP, reqData.DNS.Port) if util.ErrorIsAddrInUse(err) { canAutofix := checkDNSStubListener() if canAutofix && reqData.DNS.Autofix { err = disableDNSStubListener() if err != nil { log.Error("Couldn't disable DNSStubListener: %s", err) } err = util.CheckPacketPortAvailable(reqData.DNS.IP, reqData.DNS.Port) canAutofix = false } respData.DNS.CanAutofix = canAutofix } if err == nil { err = util.CheckPortAvailable(reqData.DNS.IP, reqData.DNS.Port) } if err != nil { respData.DNS.Status = fmt.Sprintf("%v", err) } else if reqData.DNS.IP != "0.0.0.0" { respData.StaticIP = handleStaticIP(reqData.DNS.IP, reqData.SetStaticIP) } } w.Header().Set("Content-Type", "application/json") err = json.NewEncoder(w).Encode(respData) if err != nil { httpError(w, http.StatusInternalServerError, "Unable to marshal JSON: %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 string, set bool) staticIPJSON { resp := staticIPJSON{} interfaceName := util.GetInterfaceByIP(ip) resp.Static = "no" if len(interfaceName) == 0 { resp.Static = "error" resp.Error = fmt.Sprintf("Couldn't find network interface by IP %s", ip) return resp } if set { // Try to set static IP for the specified interface err := dhcpd.SetStaticIP(interfaceName) if err != nil { resp.Static = "error" resp.Error = err.Error() return resp } } // Fallthrough here even if we set static IP // Check if we have a static IP and return the details isStaticIP, err := dhcpd.HasStaticIP(interfaceName) if err != nil { resp.Static = "error" resp.Error = err.Error() } else { if isStaticIP { resp.Static = "yes" } resp.IP = util.GetSubnet(interfaceName) } return resp } // Check if DNSStubListener is active func checkDNSStubListener() bool { if runtime.GOOS != "linux" { return false } cmd := exec.Command("systemctl", "is-enabled", "systemd-resolved") log.Tracef("executing %s %v", cmd.Path, cmd.Args) _, err := cmd.Output() if err != nil || cmd.ProcessState.ExitCode() != 0 { log.Info("command %s has failed: %v code:%d", cmd.Path, err, cmd.ProcessState.ExitCode()) return false } cmd = exec.Command("grep", "-E", "#?DNSStubListener=yes", "/etc/systemd/resolved.conf") log.Tracef("executing %s %v", cmd.Path, cmd.Args) _, err = cmd.Output() if err != nil || cmd.ProcessState.ExitCode() != 0 { log.Info("command %s has failed: %v code:%d", cmd.Path, err, cmd.ProcessState.ExitCode()) return false } return true } const ( resolvedConfPath = "/etc/systemd/resolved.conf.d/adguardhome.conf" resolvedConfData = `[Resolve] DNS=127.0.0.1 DNSStubListener=no ` ) const resolvConfPath = "/etc/resolv.conf" // Deactivate DNSStubListener func disableDNSStubListener() error { dir := filepath.Dir(resolvedConfPath) err := os.MkdirAll(dir, 0o755) if err != nil { return fmt.Errorf("os.MkdirAll: %s: %w", dir, err) } err = ioutil.WriteFile(resolvedConfPath, []byte(resolvedConfData), 0o644) if err != nil { return fmt.Errorf("ioutil.WriteFile: %s: %w", resolvedConfPath, err) } _ = os.Rename(resolvConfPath, resolvConfPath+".backup") err = os.Symlink("/run/systemd/resolve/resolv.conf", resolvConfPath) if err != nil { _ = os.Remove(resolvedConfPath) // remove the file we've just created return fmt.Errorf("os.Symlink: %s: %w", resolvConfPath, err) } cmd := exec.Command("systemctl", "reload-or-restart", "systemd-resolved") log.Tracef("executing %s %v", cmd.Path, cmd.Args) _, err = cmd.Output() if err != nil { return err } if cmd.ProcessState.ExitCode() != 0 { return fmt.Errorf("process %s exited with an error: %d", cmd.Path, cmd.ProcessState.ExitCode()) } return nil } type applyConfigReqEnt struct { IP string `json:"ip"` Port int `json:"port"` } type applyConfigReq struct { Web applyConfigReqEnt `json:"web"` DNS applyConfigReqEnt `json:"dns"` Username string `json:"username"` Password string `json:"password"` } // Copy installation parameters between two configuration objects func copyInstallSettings(dst *configuration, src *configuration) { dst.BindHost = src.BindHost dst.BindPort = src.BindPort dst.DNS.BindHost = src.DNS.BindHost dst.DNS.Port = src.DNS.Port } // Apply new configuration, start DNS server, restart Web server func (web *Web) handleInstallConfigure(w http.ResponseWriter, r *http.Request) { newSettings := applyConfigReq{} err := json.NewDecoder(r.Body).Decode(&newSettings) if err != nil { httpError(w, http.StatusBadRequest, "Failed to parse 'configure' JSON: %s", err) return } if newSettings.Web.Port == 0 || newSettings.DNS.Port == 0 { httpError(w, http.StatusBadRequest, "port value can't be 0") return } restartHTTP := true if config.BindHost == newSettings.Web.IP && config.BindPort == newSettings.Web.Port { // no need to rebind restartHTTP = false } // validate that hosts and ports are bindable if restartHTTP { err = util.CheckPortAvailable(newSettings.Web.IP, newSettings.Web.Port) if err != nil { httpError(w, http.StatusBadRequest, "Impossible to listen on IP:port %s due to %s", net.JoinHostPort(newSettings.Web.IP, strconv.Itoa(newSettings.Web.Port)), err) return } } err = util.CheckPacketPortAvailable(newSettings.DNS.IP, newSettings.DNS.Port) if err != nil { httpError(w, http.StatusBadRequest, "%s", err) return } err = util.CheckPortAvailable(newSettings.DNS.IP, newSettings.DNS.Port) if err != nil { httpError(w, http.StatusBadRequest, "%s", err) return } var curConfig configuration copyInstallSettings(&curConfig, &config) Context.firstRun = false config.BindHost = newSettings.Web.IP config.BindPort = newSettings.Web.Port config.DNS.BindHost = newSettings.DNS.IP config.DNS.Port = newSettings.DNS.Port err = StartMods() if err != nil { Context.firstRun = true copyInstallSettings(&config, &curConfig) httpError(w, http.StatusInternalServerError, "%s", err) return } u := User{} u.Name = newSettings.Username Context.auth.UserAdd(&u, newSettings.Password) err = config.write() if err != nil { Context.firstRun = true copyInstallSettings(&config, &curConfig) httpError(w, http.StatusInternalServerError, "Couldn't write config: %s", err) return } web.conf.firstRun = false web.conf.BindHost = newSettings.Web.IP web.conf.BindPort = newSettings.Web.Port registerControlHandlers() returnOK(w) if f, ok := w.(http.Flusher); ok { f.Flush() } // this needs to be done in a goroutine because Shutdown() is a blocking call, and it will block // until all requests are finished, and _we_ are inside a request right now, so it will block indefinitely if restartHTTP { go func() { _ = Context.web.httpServer.Shutdown(context.TODO()) }() } } func (web *Web) registerInstallHandlers() { Context.mux.HandleFunc("/control/install/get_addresses", preInstall(ensureGET(web.handleInstallGetAddresses))) Context.mux.HandleFunc("/control/install/check_config", preInstall(ensurePOST(web.handleInstallCheckConfig))) Context.mux.HandleFunc("/control/install/configure", preInstall(ensurePOST(web.handleInstallConfigure))) }