Add OgHttp2Session support for SETTINGS ack callbacks and apply to MAX_CONCURRENT_STREAMS.

This CL adds support to OgHttp2Session for applying sent SETTINGS parameters on
receipt of a SETTINGS ack from the peer. This support is in line with behavior
in both nghttp2 [1] and Http2Dispatcher [2].

This CL also uses this newly added support to enforce locally sent
MAX_CONCURRENT_STREAMS on ack. Note that Envoy behavior currently assumes that
peer violations of MAX_CONCURRENT_STREAMS are connection-level [3, 4], so
OgHttp2Session treats violations as a PROTOCOL_ERROR for parity with Envoy.

With this change, Http2FloodMitigationTest.TooManyStreams now passes with
oghttp2, completing flood frame mitigation integration test parity.

Before: http://sponge2/6275a2b6-178b-4ea7-b819-dbd0103564da
After: http://sponge2/463d751a-22df-446f-872c-2a6015c52969

[1] http://google3/third_party/nghttp2/src/lib/nghttp2_session.c;l=7065-7088;rcl=409864218
[2] http://google3/gfe/gfe2/http2/http2_dispatcher.h;l=1185;rcl=410682472
[3] http://google3/third_party/nghttp2/src/lib/nghttp2_session.c;l=3880-3884;rcl=410682472
[4] http://google3/third_party/envoy/src/source/common/http/http2/;l=1180,1192;rcl=410881808

PiperOrigin-RevId: 413288939
6 files changed
tree: 79fe975b4ee19996d1c385505994ab1672a12317
  1. common/
  2. epoll_server/
  3. http2/
  4. quic/
  5. spdy/


QUICHE stands for QUIC, Http/2, Etc. It is Google‘s production-ready implementation of QUIC, HTTP/2, HTTP/3, and related protocols and tools. It powers Google’s servers, Chromium, Envoy, and other projects. It is actively developed and maintained.

There are two public QUICHE repositories. Either one may be used by embedders, as they are automatically kept in sync:

To embed QUICHE in your project, platform APIs need to be implemented and build files need to be created. Note that it is on the QUICHE team's roadmap to include default implementation for all platform APIs and to open-source build files. In the meanwhile, take a look at open source embedders like Chromium and Envoy to get started:

To contribute to QUICHE, follow instructions at

QUICHE is only supported on little-endian platforms.