Previously, if an invalid SMTP command was split between reads, nginx failed
to wait for LF before returning an error, and interpreted the rest of the
command received later as a separate command.
The sw_invalid state in ngx_mail_smtp_parse_command(), introduced in
04e43d03e153, did not work, since ngx_mail_smtp_auth_state() clears
s->state when returning an error due to NGX_MAIL_PARSE_INVALID_COMMAND.
And not clearing s->state will introduce another problem: the rest
of the command would trigger duplicate error when rest of the command is
received.
Fix is to return NGX_AGAIN from ngx_mail_smtp_parse_command() until full
command is received.
Previously, if there were some pipelined SMTP data in the buffer when
a proxied connection with the backend was established, nginx called
ngx_mail_proxy_handler() to send these data, and not tried to send the
response to the last command. In most cases, this response was later sent
along with the response to the pipelined command, but if for some reason
client decides to wait for the response before finishing the next command
this might result in a connection hang.
Fix is to always call ngx_mail_proxy_handler() to send the response, and
additionally post an event to send the pipelined data if needed.
When using server push, a segfault occured because
ngx_http_v3_create_push_request() accessed ngx_http_v3_session_t object the old
way. Prior to 9ec3e71f8a61, HTTP/3 session was stored directly in c->data.
Now it's referenced by the v3_session field of ngx_http_connection_t.
With this change, it is now possible to use ngx_conf_merge_ptr_value()
to merge complex values. This change follows much earlier changes in
ngx_conf_merge_ptr_value() and ngx_conf_set_str_array_slot()
in 1452:cd586e963db0 (0.6.10) and 1701:40d004d95d88 (0.6.22), and the
change in ngx_conf_set_keyval_slot() (7728:485dba3e2a01, 1.19.4).
To preserve compatibility with existing 3rd party modules, both NULL
and NGX_CONF_UNSET_PTR are accepted for now.
Client IDs cannot be reused on different paths. This change allows to reuse
client id previosly seen on the same path (but with different dcid) in case
when no unused client IDs are available.
According to quic-transport, 9.1:
PATH_CHALLENGE, PATH_RESPONSE, NEW_CONNECTION_ID, and PADDING frames
are "probing frames", and all other frames are "non-probing frames".
Previously it was parsed in ngx_http_v3_streams.c, while the streams were
parsed in ngx_http_v3_parse.c. Now all parsing is done in one file. This
simplifies parsing API and cleans up ngx_http_v3_streams.c.
Previously, an ngx_http_v3_connection_t object was created for HTTP/3 and
then assinged to c->data instead of the generic ngx_http_connection_t object.
Now a direct reference is added to ngx_http_connection_t, which is less
confusing and does not require a flag for http3.
It's used instead of accessing c->quic->parent->data directly. Apart from being
simpler, it allows to change the way session is stored in the future by changing
the macro.
Now ngx_http_v3_ack_header() and ngx_http_v3_inc_insert_count() always generate
decoder error. Our implementation does not use dynamic tables and does not
expect client to send Section Acknowledgement or Insert Count Increment.
Stream Cancellation, on the other hand, is allowed to be sent anyway. This is
why ngx_http_v3_cancel_stream() does not return an error.
The patch adds proper transitions between multiple networking addresses that
can be used by a single quic connection. New networking paths are validated
using PATH_CHALLENGE/PATH_RESPONSE frames.
Due to structure's alignment, some uninitialized memory contents may have
been passed between processes.
Zeroing was removed in 0215ec9aaa8a.
Reported by Johnny Wang.
7.2.1:
If a DATA frame is received on a control stream, the recipient MUST
respond with a connection error of type H3_FRAME_UNEXPECTED;
7.2.2:
If a HEADERS frame is received on a control stream, the recipient MUST
respond with a connection error (Section 8) of type H3_FRAME_UNEXPECTED.
With SMTP pipelining, ngx_mail_read_command() can be called with s->buffer
without any space available, to parse additional commands received to the
buffer on previous calls. Previously, this resulted in recv() being called
with zero length, resulting in zero being returned, which was interpreted
as a connection close by the client, so nginx silently closed connection.
Fix is to avoid calling c->recv() if there is no free space in the buffer,
but continue parsing of the already received commands.
Currently both names are used which is confusing. Historically these were
different objects, but now it's the same one. The name qs (quic stream) makes
more sense than sn (stream node).
PATH_RESPONSE was explicitly forbidden in 0-RTT since at least draft-22, but
the Frame Types table was not updated until recently while in IESG evaluation.
Stop including QUIC headers with no user-serviceable parts inside.
This allows to provide a much cleaner QUIC interface. To cope with that,
ngx_quic_derive_key() is now explicitly exported for v3 and quic modules.
Additionally, this completely hides the ngx_quic_keys_t internal type.
The "ngx_event_quic.h" header file now contains only public definitions,
used by modules. All internal definitions are moved into
the "ngx_event_quic_connection.h" header file.
The function correctly cleans up resources in case of failure to create
initial server id: it removes previously created udp node for odcid from
listening rbtree.
It turns out no browsers implement HTTP/2 GOAWAY handling properly, and
large enough number of resources on a page results in failures to load
some resources. In particular, Chrome seems to experience errors if
loading of all resources requires more than 1 connection (while it
is usually able to retry requests at least once, even with 2 connections
there are occasional failures for some reason), Safari if loading requires
more than 3 connections, and Firefox if loading requires more than 10
connections (can be configured with network.http.request.max-attempts,
defaults to 10).
It does not seem to be possible to resolve this on nginx side, even strict
limiting of maximum concurrency does not help, and loading issues seems to
be triggered by merely queueing of a request for a particular connection.
The only available mitigation seems to use higher keepalive_requests value.
The new default is 1000 and matches previously used default for
http2_max_requests. It is expected to be enough for 99.98% of the pages
(https://httparchive.org/reports/state-of-the-web?start=latest#reqTotal)
even in Chrome.
Similar to lingering_time, it limits total connection lifetime before
keepalive is switched off. The default is 1 hour, which is close to
the total maximum connection lifetime possible with default
keepalive_requests and keepalive_timeout.
