Now "listen" directve has a new "quic" parameter which enables QUIC protocol
for the address. Further, to enable HTTP/3, a new directive "http3" is
introduced. The hq-interop protocol is enabled by "http3_hq" as before.
Now application protocol is chosen by ALPN.
Previously used "http3" parameter of "listen" is deprecated.
It's called after handshake completion or prior to the first early data stream
creation. The callback should initialize application-level data before
creating streams.
HTTP/3 callback implementation sets keepalive timer and sends SETTINGS.
Also, this allows to limit max handshake time in ngx_http_v3_init_stream().
Now main QUIC connection for HTTP/3 always has c->idle flag set. This allows
the connection to receive worker shutdown notification. It is passed to
application level via a new conf->shutdown() callback.
The HTTP/3 shutdown callback sends GOAWAY to client and gracefully shuts down
the QUIC connection.
Directives that set transport parameters are removed from the configuration.
Corresponding values are derived from the quic configuration or initialized
to default. Whenever possible, quic configuration parameters are taken from
higher-level protocol settings, i.e. HTTP/3.
A new variable $http3 is added. The variable equals to "h3" for HTTP/3
connections, "hq" for hq connections and is an empty string otherwise.
The variable $quic is eliminated.
The new variable is similar to $http2 variable.
Previously dynamic table was not functional because of zero limit on its size
set by default. Now the following changes enable it:
- new directives to set SETTINGS_QPACK_MAX_TABLE_CAPACITY and
SETTINGS_QPACK_BLOCKED_STREAMS
- send settings with SETTINGS_QPACK_MAX_TABLE_CAPACITY and
SETTINGS_QPACK_BLOCKED_STREAMS to the client
- send Insert Count Increment to the client
- send Header Acknowledgement to the client
- evict old dynamic table entries on overflow
- decode Required Insert Count from client
- block stream if Required Insert Count is not reached
Client streams may send literal strings which are now limited in size by the
new directive. The default value is 4096.
The directive is similar to HTTP/2 directive http2_max_field_size.
+ MAX_STREAM_DATA frame is sent when recv() is performed on stream
The new value is a sum of total bytes received by stream + free
space in a buffer;
The sending of MAX_STREM_DATA frame in response to STREAM_DATA_BLOCKED
frame is adjusted to follow the same logic as above.
+ MAX_DATA frame is sent when total amount of received data is 2x
of current limit. The limit is doubled.
+ Default values of transport parameters are adjusted to more meaningful
values:
initial stream limits are set to quic buffer size instead of
unrealistically small 255.
initial max data is decreased to 16 buffer sizes, in an assumption that
this is enough for a relatively short connection, instead of randomly
chosen big number.
All this allows to initiate a stable flow of streams that does not block
on stream/connection limits (tested with FF 77.0a1 and 100K requests)
- integer parameters can be configured using the following directives:
quic_max_idle_timeout
quic_max_ack_delay
quic_max_packet_size
quic_initial_max_data
quic_initial_max_stream_data_bidi_local
quic_initial_max_stream_data_bidi_remote
quic_initial_max_stream_data_uni
quic_initial_max_streams_bidi
quic_initial_max_streams_uni
quic_ack_delay_exponent
quic_active_migration
quic_active_connection_id_limit
- only following parameters are actually sent:
active_connection_id_limit
initial_max_streams_uni
initial_max_streams_bidi
initial_max_stream_data_bidi_local
initial_max_stream_data_bidi_remote
initial_max_stream_data_uni
(other parameters are to be added into ngx_quic_create_transport_params()
function as needed, should be easy now)
- draft 24 and draft 27 are now supported
(at compile-time using quic_version macro)
Roman Arutyunyan
Vladimir Homutov
Sergey Kandaurov