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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 07:34:15 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 07:34:15 +0000 |
commit | afea5f9539cbf1eeaa85ec77d79eb2f59724f470 (patch) | |
tree | 2a4eba394a6bc60d2eaa8304d91168a07225d51e /integration-tests/server_tester.go | |
parent | Initial commit. (diff) | |
download | nghttp2-afea5f9539cbf1eeaa85ec77d79eb2f59724f470.tar.xz nghttp2-afea5f9539cbf1eeaa85ec77d79eb2f59724f470.zip |
Adding upstream version 1.52.0.upstream/1.52.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | integration-tests/server_tester.go | 895 |
1 files changed, 895 insertions, 0 deletions
diff --git a/integration-tests/server_tester.go b/integration-tests/server_tester.go new file mode 100644 index 0000000..f98a04a --- /dev/null +++ b/integration-tests/server_tester.go @@ -0,0 +1,895 @@ +package nghttp2 + +import ( + "bufio" + "bytes" + "context" + "crypto/tls" + "encoding/binary" + "errors" + "fmt" + "io" + "net" + "net/http" + "net/http/httptest" + "net/url" + "os" + "os/exec" + "sort" + "strconv" + "strings" + "syscall" + "testing" + "time" + + "github.com/lucas-clemente/quic-go/http3" + "github.com/tatsuhiro-t/go-nghttp2" + "golang.org/x/net/http2" + "golang.org/x/net/http2/hpack" + "golang.org/x/net/websocket" +) + +const ( + serverBin = buildDir + "/src/nghttpx" + serverPort = 3009 + testDir = sourceDir + "/integration-tests" + logDir = buildDir + "/integration-tests" +) + +func pair(name, value string) hpack.HeaderField { + return hpack.HeaderField{ + Name: name, + Value: value, + } +} + +type serverTester struct { + cmd *exec.Cmd // test frontend server process, which is test subject + url string // test frontend server URL + t *testing.T + ts *httptest.Server // backend server + frontendHost string // frontend server host + backendHost string // backend server host + conn net.Conn // connection to frontend server + h2PrefaceSent bool // HTTP/2 preface was sent in conn + nextStreamID uint32 // next stream ID + fr *http2.Framer // HTTP/2 framer + headerBlkBuf bytes.Buffer // buffer to store encoded header block + enc *hpack.Encoder // HTTP/2 HPACK encoder + header http.Header // received header fields + dec *hpack.Decoder // HTTP/2 HPACK decoder + authority string // server's host:port + frCh chan http2.Frame // used for incoming HTTP/2 frame + errCh chan error +} + +type options struct { + // args is the additional arguments to nghttpx. + args []string + // handler is the handler to handle the request. It defaults + // to noopHandler. + handler http.HandlerFunc + // connectPort is the server side port where client connection + // is made. It defaults to serverPort. + connectPort int + // tls, if set to true, sets up TLS frontend connection. + tls bool + // tlsConfig is the client side TLS configuration that is used + // when tls is true. + tlsConfig *tls.Config + // tcpData is additional data that are written to connection + // before TLS handshake starts. This field is ignored if tls + // is false. + tcpData []byte + // quic, if set to true, sets up QUIC frontend connection. + // quic implies tls = true. + quic bool +} + +// newServerTester creates test context. +func newServerTester(t *testing.T, opts options) *serverTester { + if opts.quic { + opts.tls = true + } + + if opts.handler == nil { + opts.handler = noopHandler + } + if opts.connectPort == 0 { + opts.connectPort = serverPort + } + + ts := httptest.NewUnstartedServer(opts.handler) + + var args []string + var backendTLS, dns, externalDNS, acceptProxyProtocol, redirectIfNotTLS, affinityCookie, alpnH1 bool + + for _, k := range opts.args { + switch k { + case "--http2-bridge": + backendTLS = true + case "--dns": + dns = true + case "--external-dns": + dns = true + externalDNS = true + case "--accept-proxy-protocol": + acceptProxyProtocol = true + case "--redirect-if-not-tls": + redirectIfNotTLS = true + case "--affinity-cookie": + affinityCookie = true + case "--alpn-h1": + alpnH1 = true + default: + args = append(args, k) + } + } + if backendTLS { + nghttp2.ConfigureServer(ts.Config, &nghttp2.Server{}) + // According to httptest/server.go, we have to set + // NextProtos separately for ts.TLS. NextProtos set + // in nghttp2.ConfigureServer is effectively ignored. + ts.TLS = new(tls.Config) + ts.TLS.NextProtos = append(ts.TLS.NextProtos, "h2") + ts.StartTLS() + args = append(args, "-k") + } else { + ts.Start() + } + scheme := "http" + if opts.tls { + scheme = "https" + args = append(args, testDir+"/server.key", testDir+"/server.crt") + } + + backendURL, err := url.Parse(ts.URL) + if err != nil { + t.Fatalf("Error parsing URL from httptest.Server: %v", err) + } + + // URL.Host looks like "127.0.0.1:8080", but we want + // "127.0.0.1,8080" + b := "-b" + if !externalDNS { + b += fmt.Sprintf("%v;", strings.Replace(backendURL.Host, ":", ",", -1)) + } else { + sep := strings.LastIndex(backendURL.Host, ":") + if sep == -1 { + t.Fatalf("backendURL.Host %v does not contain separator ':'", backendURL.Host) + } + // We use awesome service nip.io. + b += fmt.Sprintf("%v.nip.io,%v;", backendURL.Host[:sep], backendURL.Host[sep+1:]) + } + + if backendTLS { + b += ";proto=h2;tls" + } + if dns { + b += ";dns" + } + + if redirectIfNotTLS { + b += ";redirect-if-not-tls" + } + + if affinityCookie { + b += ";affinity=cookie;affinity-cookie-name=affinity;affinity-cookie-path=/foo/bar" + } + + noTLS := ";no-tls" + if opts.tls { + noTLS = "" + } + + var proxyProto string + if acceptProxyProtocol { + proxyProto = ";proxyproto" + } + + args = append(args, fmt.Sprintf("-f127.0.0.1,%v%v%v", serverPort, noTLS, proxyProto), b, + "--errorlog-file="+logDir+"/log.txt", "-LINFO") + + if opts.quic { + args = append(args, + fmt.Sprintf("-f127.0.0.1,%v;quic", serverPort), + "--no-quic-bpf") + } + + authority := fmt.Sprintf("127.0.0.1:%v", opts.connectPort) + + st := &serverTester{ + cmd: exec.Command(serverBin, args...), + t: t, + ts: ts, + url: fmt.Sprintf("%v://%v", scheme, authority), + frontendHost: fmt.Sprintf("127.0.0.1:%v", serverPort), + backendHost: backendURL.Host, + nextStreamID: 1, + authority: authority, + frCh: make(chan http2.Frame), + errCh: make(chan error), + } + + st.cmd.Stdout = os.Stdout + st.cmd.Stderr = os.Stderr + + if err := st.cmd.Start(); err != nil { + st.t.Fatalf("Error starting %v: %v", serverBin, err) + } + + retry := 0 + for { + time.Sleep(50 * time.Millisecond) + + conn, err := net.Dial("tcp", authority) + if err == nil && opts.tls { + if len(opts.tcpData) > 0 { + if _, err := conn.Write(opts.tcpData); err != nil { + st.Close() + st.t.Fatal("Error writing TCP data") + } + } + + var tlsConfig *tls.Config + if opts.tlsConfig == nil { + tlsConfig = new(tls.Config) + } else { + tlsConfig = opts.tlsConfig.Clone() + } + tlsConfig.InsecureSkipVerify = true + if alpnH1 { + tlsConfig.NextProtos = []string{"http/1.1"} + } else { + tlsConfig.NextProtos = []string{"h2"} + } + tlsConn := tls.Client(conn, tlsConfig) + err = tlsConn.Handshake() + if err == nil { + conn = tlsConn + } + } + if err != nil { + retry++ + if retry >= 100 { + st.Close() + st.t.Fatalf("Error server is not responding too long; server command-line arguments may be invalid") + } + continue + } + st.conn = conn + break + } + + st.fr = http2.NewFramer(st.conn, st.conn) + st.enc = hpack.NewEncoder(&st.headerBlkBuf) + st.dec = hpack.NewDecoder(4096, func(f hpack.HeaderField) { + st.header.Add(f.Name, f.Value) + }) + + return st +} + +func (st *serverTester) Close() { + if st.conn != nil { + st.conn.Close() + } + if st.cmd != nil { + done := make(chan struct{}) + go func() { + if err := st.cmd.Wait(); err != nil { + st.t.Errorf("Error st.cmd.Wait() = %v", err) + } + close(done) + }() + + if err := st.cmd.Process.Signal(syscall.SIGQUIT); err != nil { + st.t.Errorf("Error st.cmd.Process.Signal() = %v", err) + } + + select { + case <-done: + case <-time.After(10 * time.Second): + if err := st.cmd.Process.Kill(); err != nil { + st.t.Errorf("Error st.cmd.Process.Kill() = %v", err) + } + <-done + } + } + if st.ts != nil { + st.ts.Close() + } +} + +func (st *serverTester) readFrame() (http2.Frame, error) { + go func() { + f, err := st.fr.ReadFrame() + if err != nil { + st.errCh <- err + return + } + st.frCh <- f + }() + + select { + case f := <-st.frCh: + return f, nil + case err := <-st.errCh: + return nil, err + case <-time.After(5 * time.Second): + return nil, errors.New("timeout waiting for frame") + } +} + +type requestParam struct { + name string // name for this request to identify the request in log easily + streamID uint32 // stream ID, automatically assigned if 0 + method string // method, defaults to GET + scheme string // scheme, defaults to http + authority string // authority, defaults to backend server address + path string // path, defaults to / + header []hpack.HeaderField // additional request header fields + body []byte // request body + trailer []hpack.HeaderField // trailer part + httpUpgrade bool // true if upgraded to HTTP/2 through HTTP Upgrade + noEndStream bool // true if END_STREAM should not be sent +} + +// wrapper for request body to set trailer part +type chunkedBodyReader struct { + trailer []hpack.HeaderField + trailerWritten bool + body io.Reader + req *http.Request +} + +func (cbr *chunkedBodyReader) Read(p []byte) (n int, err error) { + // document says that we have to set http.Request.Trailer + // after request was sent and before body returns EOF. + if !cbr.trailerWritten { + cbr.trailerWritten = true + for _, h := range cbr.trailer { + cbr.req.Trailer.Set(h.Name, h.Value) + } + } + return cbr.body.Read(p) +} + +func (st *serverTester) websocket(rp requestParam) *serverResponse { + urlstring := st.url + "/echo" + + config, err := websocket.NewConfig(urlstring, st.url) + if err != nil { + st.t.Fatalf("websocket.NewConfig(%q, %q) returned error: %v", urlstring, st.url, err) + } + + config.Header.Add("Test-Case", rp.name) + for _, h := range rp.header { + config.Header.Add(h.Name, h.Value) + } + + ws, err := websocket.NewClient(config, st.conn) + if err != nil { + st.t.Fatalf("Error creating websocket client: %v", err) + } + + if _, err := ws.Write(rp.body); err != nil { + st.t.Fatalf("ws.Write() returned error: %v", err) + } + + msg := make([]byte, 1024) + var n int + if n, err = ws.Read(msg); err != nil { + st.t.Fatalf("ws.Read() returned error: %v", err) + } + + res := &serverResponse{ + body: msg[:n], + } + + return res +} + +func (st *serverTester) http3(rp requestParam) (*serverResponse, error) { + rt := &http3.RoundTripper{ + TLSClientConfig: &tls.Config{ + InsecureSkipVerify: true, + }, + } + + defer rt.Close() + + c := &http.Client{ + Transport: rt, + } + + method := "GET" + if rp.method != "" { + method = rp.method + } + + var body io.Reader + + if rp.body != nil { + body = bytes.NewBuffer(rp.body) + } + + reqURL := st.url + + if rp.path != "" { + u, err := url.Parse(st.url) + if err != nil { + st.t.Fatalf("Error parsing URL from st.url %v: %v", st.url, err) + } + u.Path = "" + u.RawQuery = "" + reqURL = u.String() + rp.path + } + + ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second) + defer cancel() + + req, err := http.NewRequestWithContext(ctx, method, reqURL, body) + if err != nil { + return nil, err + } + + for _, h := range rp.header { + req.Header.Add(h.Name, h.Value) + } + + req.Header.Add("Test-Case", rp.name) + + // TODO http3 package does not support trailer at the time of + // this writing. + + resp, err := c.Do(req) + if err != nil { + return nil, err + } + + defer resp.Body.Close() + + respBody, err := io.ReadAll(resp.Body) + if err != nil { + return nil, err + } + + res := &serverResponse{ + status: resp.StatusCode, + header: resp.Header, + body: respBody, + connClose: resp.Close, + } + + return res, nil +} + +func (st *serverTester) http1(rp requestParam) (*serverResponse, error) { + method := "GET" + if rp.method != "" { + method = rp.method + } + + var body io.Reader + var cbr *chunkedBodyReader + if rp.body != nil { + body = bytes.NewBuffer(rp.body) + if len(rp.trailer) != 0 { + cbr = &chunkedBodyReader{ + trailer: rp.trailer, + body: body, + } + body = cbr + } + } + + reqURL := st.url + + if rp.path != "" { + u, err := url.Parse(st.url) + if err != nil { + st.t.Fatalf("Error parsing URL from st.url %v: %v", st.url, err) + } + u.Path = "" + u.RawQuery = "" + reqURL = u.String() + rp.path + } + + ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second) + defer cancel() + + req, err := http.NewRequestWithContext(ctx, method, reqURL, body) + if err != nil { + return nil, err + } + for _, h := range rp.header { + req.Header.Add(h.Name, h.Value) + } + req.Header.Add("Test-Case", rp.name) + if cbr != nil { + cbr.req = req + // this makes request use chunked encoding + req.ContentLength = -1 + req.Trailer = make(http.Header) + for _, h := range cbr.trailer { + req.Trailer.Set(h.Name, "") + } + } + if err := req.Write(st.conn); err != nil { + return nil, err + } + resp, err := http.ReadResponse(bufio.NewReader(st.conn), req) + if err != nil { + return nil, err + } + respBody, err := io.ReadAll(resp.Body) + if err != nil { + return nil, err + } + resp.Body.Close() + + res := &serverResponse{ + status: resp.StatusCode, + header: resp.Header, + body: respBody, + connClose: resp.Close, + } + + return res, nil +} + +func (st *serverTester) http2(rp requestParam) (*serverResponse, error) { + st.headerBlkBuf.Reset() + st.header = make(http.Header) + + var id uint32 + if rp.streamID != 0 { + id = rp.streamID + if id >= st.nextStreamID && id%2 == 1 { + st.nextStreamID = id + 2 + } + } else { + id = st.nextStreamID + st.nextStreamID += 2 + } + + if !st.h2PrefaceSent { + st.h2PrefaceSent = true + fmt.Fprint(st.conn, "PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n") + if err := st.fr.WriteSettings(); err != nil { + return nil, err + } + } + + res := &serverResponse{ + streamID: id, + } + + streams := make(map[uint32]*serverResponse) + streams[id] = res + + if !rp.httpUpgrade { + method := "GET" + if rp.method != "" { + method = rp.method + } + _ = st.enc.WriteField(pair(":method", method)) + + scheme := "http" + if rp.scheme != "" { + scheme = rp.scheme + } + _ = st.enc.WriteField(pair(":scheme", scheme)) + + authority := st.authority + if rp.authority != "" { + authority = rp.authority + } + _ = st.enc.WriteField(pair(":authority", authority)) + + path := "/" + if rp.path != "" { + path = rp.path + } + _ = st.enc.WriteField(pair(":path", path)) + + _ = st.enc.WriteField(pair("test-case", rp.name)) + + for _, h := range rp.header { + _ = st.enc.WriteField(h) + } + + err := st.fr.WriteHeaders(http2.HeadersFrameParam{ + StreamID: id, + EndStream: len(rp.body) == 0 && len(rp.trailer) == 0 && !rp.noEndStream, + EndHeaders: true, + BlockFragment: st.headerBlkBuf.Bytes(), + }) + if err != nil { + return nil, err + } + + if len(rp.body) != 0 { + // TODO we assume rp.body fits in 1 frame + if err := st.fr.WriteData(id, len(rp.trailer) == 0 && !rp.noEndStream, rp.body); err != nil { + return nil, err + } + } + + if len(rp.trailer) != 0 { + st.headerBlkBuf.Reset() + for _, h := range rp.trailer { + _ = st.enc.WriteField(h) + } + err := st.fr.WriteHeaders(http2.HeadersFrameParam{ + StreamID: id, + EndStream: true, + EndHeaders: true, + BlockFragment: st.headerBlkBuf.Bytes(), + }) + if err != nil { + return nil, err + } + } + } +loop: + for { + fr, err := st.readFrame() + if err != nil { + return res, err + } + switch f := fr.(type) { + case *http2.HeadersFrame: + _, err := st.dec.Write(f.HeaderBlockFragment()) + if err != nil { + return res, err + } + sr, ok := streams[f.FrameHeader.StreamID] + if !ok { + st.header = make(http.Header) + break + } + sr.header = cloneHeader(st.header) + var status int + status, err = strconv.Atoi(sr.header.Get(":status")) + if err != nil { + return res, fmt.Errorf("Error parsing status code: %w", err) + } + sr.status = status + if f.StreamEnded() { + if streamEnded(res, streams, sr) { + break loop + } + } + case *http2.PushPromiseFrame: + _, err := st.dec.Write(f.HeaderBlockFragment()) + if err != nil { + return res, err + } + sr := &serverResponse{ + streamID: f.PromiseID, + reqHeader: cloneHeader(st.header), + } + streams[sr.streamID] = sr + case *http2.DataFrame: + sr, ok := streams[f.FrameHeader.StreamID] + if !ok { + break + } + sr.body = append(sr.body, f.Data()...) + if f.StreamEnded() { + if streamEnded(res, streams, sr) { + break loop + } + } + case *http2.RSTStreamFrame: + sr, ok := streams[f.FrameHeader.StreamID] + if !ok { + break + } + sr.errCode = f.ErrCode + if streamEnded(res, streams, sr) { + break loop + } + case *http2.GoAwayFrame: + if f.ErrCode == http2.ErrCodeNo { + break + } + res.errCode = f.ErrCode + res.connErr = true + break loop + case *http2.SettingsFrame: + if f.IsAck() { + break + } + if err := st.fr.WriteSettingsAck(); err != nil { + return res, err + } + } + } + sort.Sort(ByStreamID(res.pushResponse)) + return res, nil +} + +func streamEnded(mainSr *serverResponse, streams map[uint32]*serverResponse, sr *serverResponse) bool { + delete(streams, sr.streamID) + if mainSr.streamID != sr.streamID { + mainSr.pushResponse = append(mainSr.pushResponse, sr) + } + return len(streams) == 0 +} + +type serverResponse struct { + status int // HTTP status code + header http.Header // response header fields + body []byte // response body + streamID uint32 // stream ID in HTTP/2 + errCode http2.ErrCode // error code received in HTTP/2 RST_STREAM or GOAWAY + connErr bool // true if HTTP/2 connection error + connClose bool // Connection: close is included in response header in HTTP/1 test + reqHeader http.Header // http request header, currently only sotres pushed request header + pushResponse []*serverResponse // pushed response +} + +type ByStreamID []*serverResponse + +func (b ByStreamID) Len() int { + return len(b) +} + +func (b ByStreamID) Swap(i, j int) { + b[i], b[j] = b[j], b[i] +} + +func (b ByStreamID) Less(i, j int) bool { + return b[i].streamID < b[j].streamID +} + +func cloneHeader(h http.Header) http.Header { + h2 := make(http.Header, len(h)) + for k, vv := range h { + vv2 := make([]string, len(vv)) + copy(vv2, vv) + h2[k] = vv2 + } + return h2 +} + +func noopHandler(w http.ResponseWriter, r *http.Request) { + if _, err := io.ReadAll(r.Body); err != nil { + http.Error(w, fmt.Sprintf("Error io.ReadAll() = %v", err), http.StatusInternalServerError) + } +} + +type APIResponse struct { + Status string `json:"status,omitempty"` + Code int `json:"code,omitempty"` + Data map[string]interface{} `json:"data,omitempty"` +} + +type proxyProtocolV2 struct { + command proxyProtocolV2Command + sourceAddress net.Addr + destinationAddress net.Addr + additionalData []byte +} + +type proxyProtocolV2Command int + +const ( + proxyProtocolV2CommandLocal proxyProtocolV2Command = 0x0 + proxyProtocolV2CommandProxy proxyProtocolV2Command = 0x1 +) + +type proxyProtocolV2Family int + +const ( + proxyProtocolV2FamilyUnspec proxyProtocolV2Family = 0x0 + proxyProtocolV2FamilyInet proxyProtocolV2Family = 0x1 + proxyProtocolV2FamilyInet6 proxyProtocolV2Family = 0x2 + proxyProtocolV2FamilyUnix proxyProtocolV2Family = 0x3 +) + +type proxyProtocolV2Protocol int + +const ( + proxyProtocolV2ProtocolUnspec proxyProtocolV2Protocol = 0x0 + proxyProtocolV2ProtocolStream proxyProtocolV2Protocol = 0x1 + proxyProtocolV2ProtocolDgram proxyProtocolV2Protocol = 0x2 +) + +func writeProxyProtocolV2(w io.Writer, hdr proxyProtocolV2) error { + if _, err := w.Write([]byte{0x0D, 0x0A, 0x0D, 0x0A, 0x00, 0x0D, 0x0A, 0x51, 0x55, 0x49, 0x54, 0x0A}); err != nil { + return err + } + if _, err := w.Write([]byte{byte(0x20 | hdr.command)}); err != nil { + return err + } + + switch srcAddr := hdr.sourceAddress.(type) { + case *net.TCPAddr: + dstAddr := hdr.destinationAddress.(*net.TCPAddr) + if len(srcAddr.IP) != len(dstAddr.IP) { + panic("len(srcAddr.IP) != len(dstAddr.IP)") + } + var fam byte + if len(srcAddr.IP) == 4 { + fam = byte(proxyProtocolV2FamilyInet << 4) + } else { + fam = byte(proxyProtocolV2FamilyInet6 << 4) + } + fam |= byte(proxyProtocolV2ProtocolStream) + if _, err := w.Write([]byte{fam}); err != nil { + return err + } + length := uint16(len(srcAddr.IP)*2 + 4 + len(hdr.additionalData)) + if err := binary.Write(w, binary.BigEndian, length); err != nil { + return err + } + if _, err := w.Write(srcAddr.IP); err != nil { + return err + } + if _, err := w.Write(dstAddr.IP); err != nil { + return err + } + if err := binary.Write(w, binary.BigEndian, uint16(srcAddr.Port)); err != nil { + return err + } + if err := binary.Write(w, binary.BigEndian, uint16(dstAddr.Port)); err != nil { + return err + } + case *net.UnixAddr: + dstAddr := hdr.destinationAddress.(*net.UnixAddr) + if len(srcAddr.Name) > 108 { + panic("too long Unix source address") + } + if len(dstAddr.Name) > 108 { + panic("too long Unix destination address") + } + fam := byte(proxyProtocolV2FamilyUnix << 4) + switch srcAddr.Net { + case "unix": + fam |= byte(proxyProtocolV2ProtocolStream) + case "unixdgram": + fam |= byte(proxyProtocolV2ProtocolDgram) + default: + fam |= byte(proxyProtocolV2ProtocolUnspec) + } + if _, err := w.Write([]byte{fam}); err != nil { + return err + } + length := uint16(216 + len(hdr.additionalData)) + if err := binary.Write(w, binary.BigEndian, length); err != nil { + return err + } + zeros := make([]byte, 108) + if _, err := w.Write([]byte(srcAddr.Name)); err != nil { + return err + } + if _, err := w.Write(zeros[:108-len(srcAddr.Name)]); err != nil { + return err + } + if _, err := w.Write([]byte(dstAddr.Name)); err != nil { + return err + } + if _, err := w.Write(zeros[:108-len(dstAddr.Name)]); err != nil { + return err + } + default: + fam := byte(proxyProtocolV2FamilyUnspec<<4) | byte(proxyProtocolV2ProtocolUnspec) + if _, err := w.Write([]byte{fam}); err != nil { + return err + } + length := uint16(len(hdr.additionalData)) + if err := binary.Write(w, binary.BigEndian, length); err != nil { + return err + } + } + + if _, err := w.Write(hdr.additionalData); err != nil { + return err + } + + return nil +} |