package server import ( "context" "fmt" "git.zio.sh/astra/ntfy/v2/util" "io" "mime" "net/http" "net/netip" "regexp" "strings" ) var ( mimeDecoder mime.WordDecoder priorityHeaderIgnoreRegex = regexp.MustCompile(`^u=\d,\s*(i|\d)$|^u=\d$`) ) func readBoolParam(r *http.Request, defaultValue bool, names ...string) bool { value := strings.ToLower(readParam(r, names...)) if value == "" { return defaultValue } return toBool(value) } func isBoolValue(value string) bool { return value == "1" || value == "yes" || value == "true" || value == "0" || value == "no" || value == "false" } func toBool(value string) bool { return value == "1" || value == "yes" || value == "true" } func readCommaSeparatedParam(r *http.Request, names ...string) (params []string) { paramStr := readParam(r, names...) if paramStr != "" { params = make([]string, 0) for _, s := range util.SplitNoEmpty(paramStr, ",") { params = append(params, strings.TrimSpace(s)) } } return params } func readParam(r *http.Request, names ...string) string { value := readHeaderParam(r, names...) if value != "" { return value } return readQueryParam(r, names...) } func readHeaderParam(r *http.Request, names ...string) string { for _, name := range names { value := strings.TrimSpace(maybeDecodeHeader(name, r.Header.Get(name))) if value != "" { return value } } return "" } func readQueryParam(r *http.Request, names ...string) string { for _, name := range names { value := r.URL.Query().Get(strings.ToLower(name)) if value != "" { return strings.TrimSpace(value) } } return "" } func extractIPAddress(r *http.Request, behindProxy bool) netip.Addr { remoteAddr := r.RemoteAddr addrPort, err := netip.ParseAddrPort(remoteAddr) ip := addrPort.Addr() if err != nil { // This should not happen in real life; only in tests. So, using falling back to 0.0.0.0 if address unspecified ip, err = netip.ParseAddr(remoteAddr) if err != nil { ip = netip.IPv4Unspecified() if remoteAddr != "@" || !behindProxy { // RemoteAddr is @ when unix socket is used logr(r).Err(err).Warn("unable to parse IP (%s), new visitor with unspecified IP (0.0.0.0) created", remoteAddr) } } } if behindProxy && strings.TrimSpace(r.Header.Get("X-Forwarded-For")) != "" { // X-Forwarded-For can contain multiple addresses (see #328). If we are behind a proxy, // only the right-most address can be trusted (as this is the one added by our proxy server). // See https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-For for details. ips := util.SplitNoEmpty(r.Header.Get("X-Forwarded-For"), ",") realIP, err := netip.ParseAddr(strings.TrimSpace(util.LastString(ips, remoteAddr))) if err != nil { logr(r).Err(err).Error("invalid IP address %s received in X-Forwarded-For header", ip) // Fall back to regular remote address if X-Forwarded-For is damaged } else { ip = realIP } } return ip } func readJSONWithLimit[T any](r io.ReadCloser, limit int, allowEmpty bool) (*T, error) { obj, err := util.UnmarshalJSONWithLimit[T](r, limit, allowEmpty) if err == util.ErrUnmarshalJSON { return nil, errHTTPBadRequestJSONInvalid } else if err == util.ErrTooLargeJSON { return nil, errHTTPEntityTooLargeJSONBody } else if err != nil { return nil, err } return obj, nil } func withContext(r *http.Request, ctx map[contextKey]any) *http.Request { c := r.Context() for k, v := range ctx { c = context.WithValue(c, k, v) } return r.WithContext(c) } func fromContext[T any](r *http.Request, key contextKey) (T, error) { t, ok := r.Context().Value(key).(T) if !ok { return t, fmt.Errorf("cannot find key %v in request context", key) } return t, nil } // maybeDecodeHeader decodes the given header value if it is MIME encoded, e.g. "=?utf-8?q?Hello_World?=", // or returns the original header value if it is not MIME encoded. It also calls maybeIgnoreSpecialHeader // to ignore new HTTP "Priority" header. func maybeDecodeHeader(name, value string) string { decoded, err := mimeDecoder.DecodeHeader(value) if err != nil { return maybeIgnoreSpecialHeader(name, value) } return maybeIgnoreSpecialHeader(name, decoded) } // maybeIgnoreSpecialHeader ignores new HTTP "Priority" header (see https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-priority) // // Cloudflare (and potentially other providers) add this to requests when forwarding to the backend (ntfy), // so we just ignore it. If the "Priority" header is set to "u=*, i" or "u=*" (by Cloudflare), the header will be ignored. // Returning an empty string will allow the rest of the logic to continue searching for another header (x-priority, prio, p), // or in the Query parameters. func maybeIgnoreSpecialHeader(name, value string) string { if strings.ToLower(name) == "priority" && priorityHeaderIgnoreRegex.MatchString(strings.TrimSpace(value)) { return "" } return value }