nghttpx: Add SETTINGS timeout timer to Http2Upstream

src/shrpx_http2_upstream.cc

@@ -172,6 +172,51 @@ int Http2Upstream::upgrade_upstream(HttpsUpstream *http)
   return 0;
 }
 
+namespace {
+void settings_timeout_cb(evutil_socket_t fd, short what, void *arg)
+{
+  auto upstream = reinterpret_cast<Http2Upstream*>(arg);
+  ULOG(INFO, upstream) << "SETTINGS timeout";
+  if(upstream->fail_session(NGHTTP2_SETTINGS_TIMEOUT) != 0) {
+    delete upstream->get_client_handler();
+    return;
+  }
+  if(upstream->send() != 0) {
+    delete upstream->get_client_handler();
+  }
+}
+} // namespace
+
+int Http2Upstream::start_settings_timer()
+{
+  int rv;
+  // We submit SETTINGS only once
+  if(settings_timerev_) {
+    return 0;
+  }
+  settings_timerev_ = evtimer_new(handler_->get_evbase(), settings_timeout_cb,
+                                  this);
+  if(settings_timerev_ == nullptr) {
+    return -1;
+  }
+  // SETTINGS ACK timeout is 10 seconds for now
+  timeval settings_timeout = { 10, 0 };
+  rv = evtimer_add(settings_timerev_, &settings_timeout);
+  if(rv == -1) {
+    return -1;
+  }
+  return 0;
+}
+
+void Http2Upstream::stop_settings_timer()
+{
+  if(settings_timerev_ == nullptr) {
+    return;
+  }
+  event_free(settings_timerev_);
+  settings_timerev_ = nullptr;
+}
+
 namespace {
 int on_frame_recv_callback
 (nghttp2_session *session, const nghttp2_frame *frame, void *user_data)
@@ -287,6 +332,12 @@ int on_frame_recv_callback
     }
     break;
   }
+  case NGHTTP2_SETTINGS:
+    if((frame->hd.flags & NGHTTP2_FLAG_ACK) == 0) {
+      break;
+    }
+    upstream->stop_settings_timer();
+    break;
   default:
     break;
   }
@@ -327,6 +378,21 @@ int on_data_recv_callback(nghttp2_session *session,
 }
 } // namespace
 
+namespace {
+int on_frame_send_callback(nghttp2_session* session,
+                           const nghttp2_frame *frame, void *user_data)
+{
+  auto upstream = reinterpret_cast<Http2Upstream*>(user_data);
+  if(frame->hd.type == NGHTTP2_SETTINGS &&
+     (frame->hd.flags & NGHTTP2_FLAG_ACK) == 0) {
+    if(upstream->start_settings_timer() != 0) {
+      return NGHTTP2_ERR_CALLBACK_FAILURE;
+    }
+  }
+  return 0;
+}
+} // namespace
+
 namespace {
 int on_frame_not_send_callback(nghttp2_session *session,
                                const nghttp2_frame *frame,
@@ -398,7 +464,8 @@ nghttp2_error_code infer_upstream_rst_stream_error_code
 
 Http2Upstream::Http2Upstream(ClientHandler *handler)
   : handler_(handler),
-    session_(nullptr)
+    session_(nullptr),
+    settings_timerev_(nullptr)
 {
   //handler->set_bev_cb(spdy_readcb, 0, spdy_eventcb);
   handler->set_upstream_timeouts(&get_config()->spdy_upstream_read_timeout,
@@ -412,6 +479,7 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
   callbacks.on_frame_recv_callback = on_frame_recv_callback;
   callbacks.on_data_chunk_recv_callback = on_data_chunk_recv_callback;
   callbacks.on_data_recv_callback = on_data_recv_callback;
+  callbacks.on_frame_send_callback = on_frame_send_callback;
   callbacks.on_frame_not_send_callback = on_frame_not_send_callback;
   callbacks.on_frame_recv_parse_error_callback =
     on_frame_recv_parse_error_callback;
@@ -450,6 +518,9 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
 Http2Upstream::~Http2Upstream()
 {
   nghttp2_session_del(session_);
+  if(settings_timerev_) {
+    event_free(settings_timerev_);
+  }
 }
 
 int Http2Upstream::on_read()
@@ -735,6 +806,16 @@ int Http2Upstream::window_update(Downstream *downstream,
   return 0;
 }
 
+int Http2Upstream::fail_session(nghttp2_error_code error_code)
+{
+  int rv;
+  rv = nghttp2_session_fail_session(session_, error_code);
+  if(rv != 0) {
+    return -1;
+  }
+  return 0;
+}
+
 namespace {
 ssize_t spdy_data_read_callback(nghttp2_session *session,
                                 int32_t stream_id,

src/shrpx_http2_upstream.h

@@ -61,6 +61,7 @@ public:
   // To send WINDOW_UPDATE for a connection, specify nullptr to
   // |downstream|.
   int window_update(Downstream *downstream, int32_t window_size_increment);
+  int fail_session(nghttp2_error_code error_code);
   int error_reply(Downstream *downstream, unsigned int status_code);
 
   virtual void pause_read(IOCtrlReason reason);
@@ -77,6 +78,8 @@ public:
   // takes ownership of the |upstream|. This function returns 0 if it
   // succeeds, or -1.
   int upgrade_upstream(HttpsUpstream *upstream);
+  int start_settings_timer();
+  void stop_settings_timer();
 private:
   ClientHandler *handler_;
   nghttp2_session *session_;
@@ -84,6 +87,7 @@ private:
   int32_t initial_window_size_;
   DownstreamQueue downstream_queue_;
   std::unique_ptr<HttpsUpstream> pre_upstream_;
+  event *settings_timerev_;
 };
 
 } // namespace shrpx