package home import ( "encoding/json" "fmt" "net" "net/http" "net/url" "runtime" "strings" "github.com/AdguardTeam/AdGuardHome/internal/aghnet" "github.com/AdguardTeam/AdGuardHome/internal/dnsforward" "github.com/AdguardTeam/AdGuardHome/internal/version" "github.com/AdguardTeam/golibs/log" "github.com/AdguardTeam/golibs/netutil" "github.com/NYTimes/gziphandler" ) // ---------------- // helper functions // ---------------- func returnOK(w http.ResponseWriter) { _, err := fmt.Fprintf(w, "OK\n") if err != nil { httpError(w, http.StatusInternalServerError, "Couldn't write body: %s", err) } } func httpError(w http.ResponseWriter, code int, format string, args ...interface{}) { text := fmt.Sprintf(format, args...) log.Info(text) http.Error(w, text, code) } // appendDNSAddrs is a convenient helper for appending a formatted form of DNS // addresses to a slice of strings. func appendDNSAddrs(dst []string, addrs ...net.IP) (res []string) { for _, addr := range addrs { var hostport string if config.DNS.Port != defaultPortDNS { hostport = netutil.JoinHostPort(addr.String(), config.DNS.Port) } else { hostport = addr.String() } dst = append(dst, hostport) } return dst } // 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 addresss. func appendDNSAddrsWithIfaces(dst []string, src []net.IP) (res []string, err error) { ifacesAdded := false for _, h := range src { if !h.IsUnspecified() { dst = appendDNSAddrs(dst, h) continue } else if ifacesAdded { continue } // Add addresses of all network interfaces for addresses like // "0.0.0.0" and "::". var ifaces []*aghnet.NetInterface ifaces, err = aghnet.GetValidNetInterfacesForWeb() if err != nil { return nil, fmt.Errorf("cannot get network interfaces: %w", err) } for _, iface := range ifaces { dst = appendDNSAddrs(dst, iface.Addresses...) } ifacesAdded = true } return dst, nil } // collectDNSAddresses returns the list of DNS addresses the server is listening // 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 { addrs = appendDNSAddrs(addrs, net.IP{127, 0, 0, 1}) } else { addrs, err = appendDNSAddrsWithIfaces(addrs, hosts) if err != nil { return nil, fmt.Errorf("collecting dns addresses: %w", err) } } de := getDNSEncryption() if de.https != "" { addrs = append(addrs, de.https) } if de.tls != "" { addrs = append(addrs, de.tls) } if de.quic != "" { addrs = append(addrs, de.quic) } return addrs, nil } // statusResponse is a response for /control/status endpoint. type statusResponse struct { 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"` IsRunning bool `json:"running"` Version string `json:"version"` Language string `json:"language"` } func handleStatus(w http.ResponseWriter, _ *http.Request) { dnsAddrs, err := collectDNSAddresses() if err != nil { // Don't add a lot of formatting, since the error is already // wrapped by collectDNSAddresses. httpError(w, http.StatusInternalServerError, "%s", err) return } var resp statusResponse func() { config.RLock() defer config.RUnlock() resp = statusResponse{ DNSAddrs: dnsAddrs, DNSPort: config.DNS.Port, HTTPPort: config.BindPort, IsRunning: isRunning(), Version: version.Version(), Language: config.Language, } }() var c *dnsforward.FilteringConfig if Context.dnsServer != nil { c = &dnsforward.FilteringConfig{} Context.dnsServer.WriteDiskConfig(c) resp.IsProtectionEnabled = c.ProtectionEnabled } // IsDHCPAvailable field is now false by default for Windows. if runtime.GOOS != "windows" { resp.IsDHCPAvailable = Context.dhcpServer != nil } w.Header().Set("Content-Type", "application/json") err = json.NewEncoder(w).Encode(resp) if err != nil { httpError(w, http.StatusInternalServerError, "Unable to write response json: %s", err) return } } type profileJSON struct { Name string `json:"name"` } 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 { httpError(w, http.StatusInternalServerError, "json.Marshal: %s", err) return } _, _ = w.Write(data) } // ------------------------ // registration of handlers // ------------------------ func registerControlHandlers() { httpRegister(http.MethodGet, "/control/status", handleStatus) httpRegister(http.MethodPost, "/control/i18n/change_language", handleI18nChangeLanguage) httpRegister(http.MethodGet, "/control/i18n/current_language", handleI18nCurrentLanguage) Context.mux.HandleFunc("/control/version.json", postInstall(optionalAuth(handleGetVersionJSON))) httpRegister(http.MethodPost, "/control/update", handleUpdate) httpRegister(http.MethodGet, "/control/profile", handleGetProfile) // No auth is necessary for DoH/DoT configurations Context.mux.HandleFunc("/apple/doh.mobileconfig", postInstall(handleMobileConfigDoH)) Context.mux.HandleFunc("/apple/dot.mobileconfig", postInstall(handleMobileConfigDoT)) RegisterAuthHandlers() } func httpRegister(method, url string, handler func(http.ResponseWriter, *http.Request)) { if method == "" { // "/dns-query" handler doesn't need auth, gzip and isn't restricted by 1 HTTP method Context.mux.HandleFunc(url, postInstall(handler)) return } Context.mux.Handle(url, postInstallHandler(optionalAuthHandler(gziphandler.GzipHandler(ensureHandler(method, handler))))) } // ---------------------------------- // helper functions for HTTP handlers // ---------------------------------- func ensure(method string, handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) { return func(w http.ResponseWriter, r *http.Request) { log.Debug("%s %v", r.Method, r.URL) 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 { Context.controlLock.Lock() defer Context.controlLock.Unlock() } handler(w, r) } } func ensurePOST(handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) { return ensure(http.MethodPost, handler) } func ensureGET(handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) { return ensure(http.MethodGet, handler) } // Bridge between http.Handler object and Go function type httpHandler struct { handler func(http.ResponseWriter, *http.Request) } func (h *httpHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { h.handler(w, r) } func ensureHandler(method string, handler func(http.ResponseWriter, *http.Request)) http.Handler { h := httpHandler{} h.handler = ensure(method, handler) return &h } // preInstall lets the handler run only if firstRun is true, no redirects func preInstall(handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) { return func(w http.ResponseWriter, r *http.Request) { if !Context.firstRun { // if it's not first run, don't let users access it (for example /install.html when configuration is done) http.Error(w, http.StatusText(http.StatusForbidden), http.StatusForbidden) return } handler(w, r) } } // preInstallStruct wraps preInstall into a struct that can be returned as an interface where necessary type preInstallHandlerStruct struct { handler http.Handler } func (p *preInstallHandlerStruct) ServeHTTP(w http.ResponseWriter, r *http.Request) { preInstall(p.handler.ServeHTTP)(w, r) } // preInstallHandler returns http.Handler interface for preInstall wrapper func preInstallHandler(handler http.Handler) http.Handler { return &preInstallHandlerStruct{handler} } // handleHTTPSRedirect redirects the request to HTTPS, if needed. If ok is // true, the middleware must continue handling the request. func handleHTTPSRedirect(w http.ResponseWriter, r *http.Request) (ok bool) { web := Context.web if web.httpsServer.server == nil { return true } host, err := netutil.SplitHost(r.Host) if err != nil { httpError(w, http.StatusBadRequest, "bad host: %s", err) return false } if r.TLS == nil && web.forceHTTPS { hostPort := host if port := web.conf.PortHTTPS; port != defaultPortHTTPS { hostPort = netutil.JoinHostPort(host, port) } httpsURL := &url.URL{ Scheme: schemeHTTPS, Host: hostPort, Path: r.URL.Path, RawQuery: r.URL.RawQuery, } http.Redirect(w, r, httpsURL.String(), http.StatusTemporaryRedirect) return false } // Allow the frontend from the HTTP origin to send requests to the HTTPS // server. This can happen when the user has just set up HTTPS with // redirects. Prevent cache-related errors by setting the Vary header. // // See https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Access-Control-Allow-Origin. originURL := &url.URL{ Scheme: schemeHTTP, Host: r.Host, } w.Header().Set("Access-Control-Allow-Origin", originURL.String()) w.Header().Set("Vary", "Origin") return true } // postInstall lets the handler to run only if firstRun is false. Otherwise, it // redirects to /install.html. It also enforces HTTPS if it is enabled and // configured and sets appropriate access control headers. func postInstall(handler func(http.ResponseWriter, *http.Request)) func(http.ResponseWriter, *http.Request) { return func(w http.ResponseWriter, r *http.Request) { path := r.URL.Path if Context.firstRun && !strings.HasPrefix(path, "/install.") && !strings.HasPrefix(path, "/assets/") { http.Redirect(w, r, "/install.html", http.StatusFound) return } if !handleHTTPSRedirect(w, r) { return } handler(w, r) } } type postInstallHandlerStruct struct { handler http.Handler } func (p *postInstallHandlerStruct) ServeHTTP(w http.ResponseWriter, r *http.Request) { postInstall(p.handler.ServeHTTP)(w, r) } func postInstallHandler(handler http.Handler) http.Handler { return &postInstallHandlerStruct{handler} }