A QUIC connection doesn't have c->log->data and friends initialized to sensible
values. Yet, a request can be created in the certificate callback with such an
assumption, which leads to a segmentation fault due to null pointer dereference
in ngx_http_free_request(). The fix is to adjust initializing the QUIC part of
a connection such that it has all of that in place.
Further, this appends logging error context for unsuccessful QUIC handshakes:
- cannot load certificate .. while handling frames
- SSL_do_handshake() failed .. while sending frames
OpenSSL library QUIC support cannot be tested at configure time when
using the --with-openssl option so assume it's present if requested.
While here, fixed the error message in case QUIC support is missing.
Previously the counter was not incremented for HTTP/3 streams, but still
decremented in ngx_http_close_connection(). There are two solutions here, one
is to increment the counter for HTTP/3 streams, and the other one is not to
decrement the counter for HTTP/3 streams. The latter solution looks
inconsistent with ngx_stat_reading/ngx_stat_writing, which are incremented on a
per-request basis. The change adds ngx_stat_active increment for HTTP/3
request and push streams.
Notably, it is to avoid setting the TCP_NODELAY flag for QUIC streams
in ngx_http_upstream_send_response(). It is an invalid operation on
inherently SOCK_DGRAM sockets, which leads to QUIC connection close.
The change reduces diff to the default branch in stream content phase.
This function was only referenced from ngx_http_v3_create_push_request() to
initialize push connection log. Now the log handler is copied from the parent
request connection.
The change reduces diff to the default branch.
The functions ngx_quic_handle_read_event() and ngx_quic_handle_write_event()
are added. Previously this code was a part of ngx_handle_read_event() and
ngx_handle_write_event().
The change simplifies ngx_handle_read_event() and ngx_handle_write_event()
by moving QUIC-related code to a QUIC source file.
Previously it had -1 as fd. This fixes proxying, which relies on downstream
connection having a real fd. Also, this reduces diff to the default branch for
ngx_close_connection().
The request body filter chain is no longer called after processing
a DATA frame. Instead, we now post a read event to do this. This
ensures that multiple small DATA frames read during the same event loop
iteration are coalesced together, resulting in much faster processing.
Since rb->buf can now contain unprocessed data, window update is no
longer sent in ngx_http_v2_state_read_data() in case of flow control
being used due to filter buffering. Instead, window will be updated
by ngx_http_v2_read_client_request_body_handler() in the posted read
event.
Following rb->filter_need_buffering changes, request body reading is
only finished after the filter chain is called and rb->last_saved is set.
As such, with r->request_body_no_buffering, timer on fc->read is no
longer removed when the last part of the body is received, potentially
resulting in incorrect behaviour.
The fix is to call ngx_http_v2_process_request_body() from the
ngx_http_v2_read_unbuffered_request_body() function instead of
directly calling ngx_http_v2_filter_request_body(), so the timer
is properly removed.
In the body read handler, the window was incorrectly calculated
based on the full buffer size instead of the amount of free space
in the buffer. If the request body is buffered by a filter, and
the buffer is not empty after the read event is generated by the
filter to resume request body processing, this could result in
"http2 negative window update" alerts.
Further, in the body ready handler and in ngx_http_v2_state_read_data()
the buffer wasn't cleared when the data were already written to disk,
so the client might stuck without window updates.
If a MAX_DATA frame was received before any stream was created, then the worker
process would crash in nginx_quic_handle_max_data_frame() while traversing the
stream tree. The issue is solved by adding a check that makes sure the tree is
not empty.
If a filter wants to buffer the request body during reading (for
example, to check an external scanner), it can now do so. To make
it possible, the code now checks rb->last_saved (introduced in the
previous change) along with rb->rest == 0.
Since in HTTP/2 this requires flow control to avoid overflowing the
request body buffer, so filters which need buffering have to set
the rb->filter_need_buffering flag on the first filter call. (Note
that each filter is expected to call the next filter, so all filters
will be able set the flag if needed.)
It indicates that the last buffer was received by the save filter,
and can be used to check this at higher levels. To be used in the
following changes.
If due to an error ngx_http_request_body_save_filter() is called
more than once with rb->rest == 0, this used to result in a segmentation
fault. Added an alert to catch such errors, just in case.
Previously, fully preread unbuffered requests larger than client body
buffer size were saved to disk, despite the fact that "unbuffered" is
expected to imply no disk buffering.
