Method rcv_headers_frame

src/proxy/http2/Http2ConnectionState.cc:292–539

* [RFC 7540] 6.2 HEADERS Frame * * NOTE: HEADERS Frame and CONTINUATION Frame * 1. A HEADERS frame with the END_STREAM flag set can be followed by * CONTINUATION frames on the same stream. * 2. A HEADERS frame without the END_HEADERS flag set MUST be followed by a * CONTINUATION frame */

 *      CONTINUATION frame
 */
Http2Error
Http2ConnectionState::rcv_headers_frame(const Http2Frame &frame)
{
  const Http2StreamId stream_id      = frame.header().streamid;
  const uint32_t      payload_length = frame.header().length;

  Http2StreamDebug(this->session, stream_id, "Received HEADERS frame");

  if (!http2_is_client_streamid(stream_id)) {
    return Http2Error(Http2ErrorClass::HTTP2_ERROR_CLASS_CONNECTION, Http2ErrorCode::HTTP2_ERROR_PROTOCOL_ERROR,
                      "recv headers bad client id");
  }

  Http2Stream *stream                      = nullptr;
  bool         new_stream                  = false;
  bool         reset_header_after_decoding = false;
  bool         free_stream_after_decoding  = false;

  if (this->is_valid_streamid(stream_id)) {
    stream = this->find_stream(stream_id);
    if (!this->session->is_outbound() && (stream == nullptr || !stream->trailing_header_is_possible())) {
      return Http2Error(Http2ErrorClass::HTTP2_ERROR_CLASS_CONNECTION, Http2ErrorCode::HTTP2_ERROR_STREAM_CLOSED,
                        "stream not expecting trailer header");
    } else if (stream == nullptr || stream->get_state() == Http2StreamState::HTTP2_STREAM_STATE_CLOSED) {
      if (this->session->is_outbound()) {
        reset_header_after_decoding = true;
        // return Http2Error(Http2ErrorClass::HTTP2_ERROR_CLASS_NONE);
        // return Http2Error(Http2ErrorClass::HTTP2_ERROR_CLASS_STREAM, Http2ErrorCode::HTTP2_ERROR_STREAM_CLOSED,
        //                  "recv_header to closed stream");
      } else {
        return Http2Error(Http2ErrorClass::HTTP2_ERROR_CLASS_CONNECTION, Http2ErrorCode::HTTP2_ERROR_STREAM_CLOSED,
                          "recv_header to closed stream");
      }
    }
  }

  if (!http2_is_client_streamid(stream_id)) {
    return Http2Error(Http2ErrorClass::HTTP2_ERROR_CLASS_CONNECTION, Http2ErrorCode::HTTP2_ERROR_PROTOCOL_ERROR,
                      "recv headers bad client id");
  }

  if (!stream) {
    if (reset_header_after_decoding) {
      free_stream_after_decoding                 = true;
      uint32_t const initial_local_stream_window = this->acknowledged_local_settings.get(HTTP2_SETTINGS_INITIAL_WINDOW_SIZE);
      ink_assert(dynamic_cast<Http2CommonSession *>(this->session->get_proxy_session()));
      ink_assert(this->session->is_outbound() == true);
      stream = THREAD_ALLOC_INIT(http2StreamAllocator, this_ethread(), this->session->get_proxy_session(), stream_id,
                                 this->peer_settings.get(HTTP2_SETTINGS_INITIAL_WINDOW_SIZE), initial_local_stream_window,
                                 !STREAM_IS_REGISTERED);
    } else {
      // Create new stream
      Http2Error error(Http2ErrorClass::HTTP2_ERROR_CLASS_NONE);
      stream     = this->create_stream(stream_id, error);
      new_stream = true;
      if (!stream) {
        // Terminate the connection with COMPRESSION_ERROR because we don't decompress the field block in this HEADERS frame.
        // TODO: try to decompress to keep HPACK Dynamic Table in sync.