Previously, if automatic window update is enabled (which is default),
after window size is set to 0 by
nghttp2_session_set_local_window_size, once the receiving window is
exhausted, even after window size is increased by
nghttp2_session_set_local_window_size, no more data cannot be
received. This is because nghttp2_session_set_local_window_size does
not submit WINDOW_UPDATE. It is only triggered when new data arrives
but since window is filled up, no more data cannot be received, thus
dead lock happens.
This commit fixes this issue. nghttp2_session_set_local_window_size
submits WINDOW_UPDATE if necessary.
https://github.com/curl/curl/issues/4939
This commit fixes the bug that stream is closed with wrong error code
(0). This happens when STREAM or DATA frame with END_STREAM flag set
is received and it violates HTTP messaging rule (i.e., content-length
does not match) and the other side of stream has been closed. In this
case, nghttp2_on_stream_close_callback should be called with nonzero
error code, but previously it is called with 0 (NO_ERROR).
The maximum number of outgoing concurrent streams is initially
limited to 100 to avoid issues when the local endpoint submits
lots of requests before receiving initial SETTINGS frame from
the remote endpoint, since sending them at once to the remote
endpoint could lead to rejection of some of the requests.
This initial limit is overwritten with the value advertised in
SETTINGS_MAX_CONCURRENT_STREAMS setting by the remote endpoint,
but previously, it wasn't lifted if the remote endpoint didn't
advertise that setting (implying no limits), in which case the
limit of 100 was retained, even though it was never advertised
by the remote endpoint.
Signed-off-by: Piotr Sikora <piotrsikora@google.com>
The error code NGHTTP2_REFUSED_STREAM is passed to
nghttp2_on_stream_close callback when a stream is closed because its
stream ID is strictly larger than incoming or outgoing GOAWAY.
nghttp2_error_callback2 is an extended version of the existing
nghttp2_error_callback by adding error code parameter. This
deprecates nghttp2_error_callback.
Previously, the incoming invalid regular header field was ignored by
default. With this commit, they are now treated as stream error, and
the stream is reset by default. The error code used is now
PROTOCOL_ERROR, instead of INTERNAL_ERROR.
This commit fixes the bug in nghttp2_session_want_write. Previously,
it may return 0 if there is pending frames after GOAWAY frame is
submitted.
To avoid the situation that nghttp2_session_want_write keeps returning
nonzero after GOAWAY and the number of active streams is 0 (e.g., keep
receiving SETTINGS or PING), nghttp2_session_mem_recv now just
swallows the input data without parsing in this case.
nghttp2_option_no_closed_streams controls whether closed streams are
retained or not. If nonzero is passed to that function's parameter
val, a session does not retain closed streams. It may hurt the shape
of priority tree, but can save memory.
Revert part of 16c46114dc to fix race
condition that incoming stream after sending GOAWAY causes connection
error. The strict stream handling introduced in the above commit does
not handle several cases well (e.g., GOAWAY race, and refusing streams
because of concurrency limit).
2 APIs are added. nghttp2_session_get_local_window_size() returns the
amount of data that the remote endpoint can send without receiving
connection level WINDOW_UPDATE.
nghttp2_session_get_stream_local_window_size() returns the amount of
data that the remote endpoint can send without receiving stream level
WINDOW_UPDATE.
Previously, in server side, we used closed streams to detect the error
that the misbehaving client sends a frame on the incoming stream it
explicitly closed. With this commit, we make a further step, and
detect one more error case. Since we retain closed streams as long as
the sum of its size and the number of opened streams are equal or less
than max concurrent streams, we can safely say that if we get a frame
which is sent on the stream that is not found in either closed or
opened stream, it is already closed or has not existed. Then we can
send GOAWAY.
The previous code shrinks closed streams when we closed another
stream, but now it is removed. It is enough to adjust closed streams
when new incoming stream is created.
While creating this commit, we noticed that
NGHTTP2_INITIAL_MAX_CONCURRENT_STREAMS is defined as INT32_MAX. But
since SETTINGS can contain value up to UINT32_MAX, it is not enough.
However, since the stream ID space is limited to INT32_MAX, it is high
enough. We could keep this value, but this time we deprecate
NGHTTP2_INITIAL_MAX_CONCURRENT_STREAMS macro. While it is in public
header, the effect of deprecating it is negligible because of the
reason we wrote above, and usually application sets much smaller value
(say, 100) as SETTINGS_MAX_CONCURRENT_STREAMS.
https://tools.ietf.org/html/rfc7540#section-5.3.3 explains how to
transform dependency tree to avoid circular dependency. Previously,
we wrongly always moved the dependent stream under the root stream.
The correct destination is the parent stream of the stream to
reprioritize. This commit fixes this bug.
Tatsuhiro Tsujikawa
Piotr Sikora
Angus Gratton
lstefani
Alexis La Goutte
Anders Bakken