546 Commits

Author SHA1 Message Date
Amaury Denoyelle
1ec78ff421 MINOR: mux-quic: complete traces for qcs emission
Add traces for _qc_send_qcs() function. Most notably, traces have been
added each time a qc_stream_desc buffer allocation fails and when stream
or connection flow-level is reached. This should improve debugging for
emission issues.

This must be backported up to 2.7.
2023-03-22 16:08:54 +01:00
Amaury Denoyelle
178fbffda1 BUG/MEDIUM: mux-quic: release data from conn flow-control on qcs reset
Connection flow-control level calculation is a bit complicated. To
ensure it is never exceeded, each time a transfer occurs from a
qcs.tx.buf to its qc_stream_desc buffer it is accounted in
qcc.tx.offsets at the connection level. This value is not decremented
even if the corresponding STREAM frame is rejected by the quic-conn
layer as its emission will be retried later.

In normal cases this works as expected. However there is an issue if a
qcs instance is removed with prepared data left. In this case, its data
is still accounted in qcc.tx.offsets despite being removed which may
block other streams. This happens every time a qcs is reset with
remaining data which will be discarded in favor of a RESET_STREAM frame.

To fix this, if a stream has prepared data in qcc_reset_stream(), it is
decremented from qcc.tx.offsets. A BUG_ON() has been added to ensure
qcs_destroy() is never called for a stream with prepared data left.

This bug can cause two issues :
* transfer freeze as data unsent from closed streams still count on the
  connection flow-control limit and will block other streams. Note that
  this issue was not reproduced so it's unsure if this really happens
  without the following issue first.
* a crash on a BUG_ON() statement in qc_send() loop over
  qc_send_frames(). Streams may remained in the send list with nothing
  to send due to connection flow-control limit. However, limit is never
  reached through qcc_streams_sent_done() so QC_CF_BLK_MFCTL flag is not
  set which will allow the loop to continue.

The last case was reproduced after several minutes of testing using the
following command :

$ ngtcp2-client --exit-on-all-streams-close -t 0.1 -r 0.1 \
  --max-data=100K -n32 \
  127.0.0.1 20443 "https://127.0.0.1:20443/?s=1g" 2>/dev/null

This should fix github issues #2049 and #2074.
2023-03-22 16:08:54 +01:00
Amaury Denoyelle
ebfafc212a BUG/MINOR: mux-quic: properly init STREAM frame as not duplicated
STREAM frame retransmission has been recently fixed. A new boolean field
<dup> was created for quic_stream frame type. It is set for duplicated
STREAM frame to ensure extra checks on the underlying buffer are
conducted before sending the frame. All of this has been implemented by
this commit :
  315a4f6ae54da17fd28f7a14373b05bab0b5aa08
  BUG/MEDIUM: quic: do not crash when handling STREAM on released MUX

However, the above commit is incomplete. In the MUX code, when a new
STREAM frame is created, <dup> is left uninitialized. In most cases this
is harmless as it will only add extra unneeded checks before sending the
frame. So this is mainly a performance issue.

There is however one case where this bug will lead to a crash : when the
response consists only of an empty STREAM frame. In this case, the empty
frame will be silently removed as it is incorrectly assimilated to an
already acked frame range in qc_build_frms(). This can trigger a
BUG_ON() on the MUX code as a qcs instance is still in the send list
after qc_send_frames() invocation.

Note that this is extremely rare to have only an empty STREAM frame. It
was reproduced with HTTP/0.9 where no HTTP status line exists on an
empty body. I do not know if this is possible on HTTP/3 as a status line
should be present each time in a HEADERS frame.

Properly initialize <dup> field to 0 on each STREAM frames generated by
the QUIC MUX to fix this issue.

This crash may be linked to github issue #2049.

This should be backported up to 2.6.
2023-03-07 18:39:49 +01:00
Amaury Denoyelle
caa16549b8 MINOR: quic: notify on send ready
This patch completes the previous one with poller subscribe of quic-conn
owned socket on sendto() error. This ensures that mux-quic is notified
if waiting on sending when a transient sendto() error is cleared. As
such, qc_notify_send() is called directly inside socket I/O callback.

qc_notify_send() internal condition have been thus completed. This will
prevent to notify upper layer until all sending condition are fulfilled:
room in congestion window and no transient error on socket FD.

This should be backported up to 2.7.
2023-03-01 14:32:37 +01:00
Christopher Faulet
85eabfbf67 MEDIUM: mux-quic: Don't expect data from server as long as request is unfinished
As for the H1 and H2 stream, the QUIC stream now states it does not expect
data from the server as long as the request is unfinished. The aim is the
same. We must be sure to not trigger a read timeout on server side if the
client is still uploading data.

From the moment the end of the request is received and forwarded to upper
layer, the QUIC stream reports it expects to receive data from the opposite
endpoint. This re-enables read timeout on the server side.
2023-02-27 17:45:45 +01:00
Amaury Denoyelle
b3aa07c78e MEDIUM: mux-quic: properly implement soft-stop
Properly implement support for haproxy soft-stop on QUIC MUX. This code
is similar to H2 MUX :

* on timeout refresh, if stop-stop in progress, schedule the timeout to
  expire with regards to the close-spread-end window.

* after input/output processing, if soft-stop in progress, shutdown the
  connection. This is randomly spread by close-spread-end window. In the
  case of H3 connection, a GOAWAY is emitted and the connection is kept
  until all data are sent for opened streams. If the client tries to use
  new streams, they are rejected in conformance with the GOAWAY
  specification.

This ensures that MUX is able to forward all content properly before
closing the connection. The lower quic-conn layer is then responsible
for retransmission and should be closed when all data are acknowledged.
This will be implemented in the next commit to fully support soft-stop
for QUIC connections.

This should be backported up to 2.7.
2023-02-20 11:20:18 +01:00
Amaury Denoyelle
eb7d320d25 MINOR: mux-quic: implement client-fin timeout
Implement client-fin timeout for MUX quic. This timeout is used once an
applicative layer shutdown has been called. In HTTP/3, this corresponds
to the emission of a GOAWAY.

This should be backported up to 2.7.
2023-02-20 11:20:18 +01:00
Amaury Denoyelle
14dbb848af MINOR: mux-quic: define qc_process()
Define a new function qc_process(). This function will regroup several
internal operation which should be called both on I/O tasklet and wake()
callback. For the moment, only streams purge is conducted there.

This patch is useful to support haproxy soft stop. This should be
backported up to 2.7.
2023-02-20 11:19:45 +01:00
Amaury Denoyelle
b30247b16c MINOR: mux-quic: define qc_shutdown()
Factorize shutdown operation in a dedicated function qc_shutdown(). This
will allow to call it from multiple places. A new flag QC_CF_APP_SHUT is
also defined to ensure it will only be executed once even if called
multiple times per connection.

This commit will be useful to properly support haproxy soft stop.
This should be backported up to 2.7.
2023-02-20 11:18:58 +01:00
Amaury Denoyelle
3d550848be MEDIUM: h3: enforce GOAWAY by resetting higher unhandled stream
When a GOAWAY has been emitted, an ID is announced to represent handled
streams. H3 RFC suggests that higher streams should be resetted with the
error code H3_REQUEST_CANCELLED. This allows the peer to replay requests
on another connection.

For the moment, the impact of this change is limitted as GOAWAY is only
used on connection shutdown just before the MUX is freed. However, for
soft-stop support, a GOAWAY can be emitted in anticipation while keeping
the MUX to finish the active streams. In this case, new streams opened
by the client are resetted.

As a consequence of this change, app_ops.attach() operation has been
delayed at the very end of qcs_new(). This ensure that all qcs members
are initialized to support RESET_STREAM sending.

This should be backported up to 2.7.
2023-02-20 11:18:25 +01:00
Amaury Denoyelle
fa241939c7 BUG/MINOR: mux-quic: transfer FIN on empty STREAM frame
Implement support for clients that emit the stream FIN with an empty
STREAM frame. For that, qcc_recv() offset comparison has been adjusted.
If offset has already been received but the FIN bit is now transmitted,
do not skip the rest of the function and call application layer
decode_qcs() callback.

Without this, streams will be kept open forever as HTX EOM is never
transfered to the upper stream layer.

This behavior was observed with mvfst client prior to its patch
  38c955a024aba753be8bf50fdeb45fba3ac23cfd
  Fix hq-interop (HTTP 0.9 over QUIC)

This notably caused the interop multiplexing test to fail as unclosed
streams on haproxy side prevented the emission of new MAX_STREAMS frame
to the client.

This shoud be backported up to 2.6. It also relies on previous commit :
  381d8137e31d941c9143a1dc8b5760d29f388fef
  MINOR: h3/hq-interop: handle no data in decode_qcs() with FIN set
2023-02-17 16:28:12 +01:00
Amaury Denoyelle
381d8137e3 MINOR: h3/hq-interop: handle no data in decode_qcs() with FIN set
Properly handle a STREAM frame with no data but the FIN bit set at the
application layer. H3 and hq-interop decode_qcs() callback have been
adjusted to not return early in this case.

If the FIN bit is accepted, a HTX EOM must be inserted for the upper
stream layer. If the FIN is rejected because the stream cannot be
closed, a proper CONNECTION_CLOSE error will be triggered.

A new utility function qcs_http_handle_standalone_fin() has been
implemented in the qmux_http module. This allows to simply add the HTX
EOM on qcs HTX buffer. If the HTX buffer is empty, a EOT is first added
to ensure it will be transmitted above.

This commit will allow to properly handle FIN notify through an empty
STREAM frame. However, it is not sufficient as currently qcc_recv() skip
the decode_qcs() invocation when the offset is already received. This
will be fixed in the next commit.

This should be backported up to 2.6 along with the next patch.
2023-02-17 16:25:00 +01:00
Frdric Lcaille
9969adbcdc MINOR: stats: add by HTTP version cumulated number of sessions and requests
Add cum_sess_ver[] new array of counters to count the number of cumulated
HTTP sessions by version (h1, h2 or h3).
Implement proxy_inc_fe_cum_sess_ver_ctr() to increment these counter.
This function is called each a HTTP mux is correctly initialized. The QUIC
must before verify the application operations for the mux is for h3 before
calling proxy_inc_fe_cum_sess_ver_ctr().
ST_F_SESS_OTHER stat field for the cumulated of sessions others than
HTTP sessions is deduced from ->cum_sess_ver counter (for all the session,
not only HTTP sessions) from which the HTTP sessions counters are substracted.

Add cum_req[] new array of counters to count the number of cumulated HTTP
requests by version and others than HTTP requests. This new member replace ->cum_req.
Modify proxy_inc_fe_req_ctr() which increments these counters to pass an HTTP
version, 0 special values meaning "other than an HTTP request". This is the case
for instance for syslog.c from which proxy_inc_fe_req_ctr() is called with 0
as version parameter.
ST_F_REQ_TOT stat field compputing for the cumulated number of requests is modified
to count the sum of all the cum_req[] counters.

As this patch is useful for QUIC, it must be backported to 2.7.
2023-02-03 17:55:49 +01:00
Amaury Denoyelle
57b3eaa793 MINOR: quic: refactor frame deallocation
Define a new function qc_frm_free() to handle frame deallocation. New
BUG_ON() statements ensure that the deallocated frame is not referenced
by other frame. To support this, all LIST_DELETE() have been replaced by
LIST_DEL_INIT(). This should enforce that frame deallocation is robust.

As a complement, qc_frm_unref() has been moved into quic_frame module.
It is justified as this is a utility function related to frame
deallocation. It allows to use it in quic_pktns_tx_pkts_release() before
calling qc_frm_free().

This should be backported up to 2.7.
2023-02-03 11:55:41 +01:00
Amaury Denoyelle
40c24f1a10 MINOR: quic: define new functions for frame alloc
Define two utility functions for quic_frame allocation :
* qc_frm_alloc() is used to allocate a new frame
* qc_frm_dup() is used to allocate a new frame by duplicating an
  existing one

Theses functions are useful to centralize quic_frame initialization.
Note that pool_zalloc() is replaced by a proper pool_alloc() + explicit
initialization code.

This commit will simplify implementation of the per frame retransmission
limitation. Indeed, a new counter will be added in quic_frame structure
which must be initialized to 0.

This should be backported up to 2.7.
2023-02-03 10:44:26 +01:00
Amaury Denoyelle
1dac018d9f MINOR: quic: ensure offset is properly set for STREAM frames
Care must be taken when reading/writing offset for STREAM frames. A
special OFF bit is set in the frame type to indicate that the field is
present. If not set, it is assumed that offset is 0.

To represent this, offset field of quic_stream structure must always be
initialized with a valid value in regards with its frame type OFF bit.

The previous code has no bug in part because pool_zalloc() is used to
allocate quic_frame instances. To be able to use pool_alloc(), offset is
always explicitely set to 0. If a non-null value is used, OFF bit is set
at the same occasion. A new BUG_ON() statement is added on frame builder
to ensure that the caller has set OFF bit if offset is non null.

This should be backported up to 2.7.
2023-02-03 09:46:55 +01:00
Amaury Denoyelle
e269aeb46b BUG/MINOR: h3: reject RESET_STREAM received for control stream
This commit is similar to the previous one. It reports an error if a
RESET_STREAM is received for the remote control stream. This will
generate a CONNECTION_CLOSE with H3_CLOSED_CRITICAL_STREAM error.

Note that contrary to the previous bug related to STOP_SENDING, this bug
was not encountered in real environment. As such, it is labelled as
MINOR. However, it could triggered the same crash as the previous patch.

This should be backported up to 2.6.
2023-01-30 16:16:46 +01:00
Amaury Denoyelle
87f8766d3f BUG/MEDIUM: h3: handle STOP_SENDING on control stream
Before this patch, STOP_SENDING reception was considered valid even on
H3 control stream. This causes the emission in return of RESET_STREAM
and eventually the closure and freeing of the QCS instance. This then
causes a crash during connection closure as a GOAWAY frame is emitted on
the control stream which is now released.

To fix this crash, STOP_SENDING on the control stream is now properly
rejected as specified by RFC 9114. The new app_ops close callback is
used which in turn will generate a CONNECTION_CLOSE with error
H3_CLOSED_CRITICAL_STREAM.

This bug was detected in github issue #2006. Note that however it is
triggered by an incorrect client behavior. It may be useful to determine
which client behaves like this. If this case is too frequent,
STOP_SENDING should probably be silently ignored.

To reproduce this issue, quiche was patched to emit a STOP_SENDING on
its send() function in quiche/src/lib.rs:
     pub fn send(&mut self, out: &mut [u8]) -> Result<(usize, SendInfo)> {
-        self.send_on_path(out, None, None)
+        let ret = self.send_on_path(out, None, None);
+        self.streams.mark_stopped(3, true, 0);
+        ret
     }

This must be backported up to 2.6 along with the preceeding commit :
  MINOR: mux-quic/h3: define close callback
2023-01-30 16:12:23 +01:00
Amaury Denoyelle
b4d119f0c7 BUG/MEDIUM: mux-quic: fix crash on H3 SETTINGS emission
A major regression was introduced by following patch
    commit 71fd03632fff43f11cebc6ff4974723c9dc81c67
    MINOR: mux-quic/h3: send SETTINGS as soon as transport is ready

H3 finalize operation is now called at an early stage in the middle of
qc_init(). However, some qcc members are not yet initialized. In
particular the stream tree which will cause a crash when H3 control
stream will be accessed.

To fix this, qcc_install_app_ops() has been delayed at the end of
qc_init(). This ensures that qcc is properly initialized when app_ops
operation are used.

This must be backported wherever above patch is. For the record, it has
been tagged up to 2.7.
2023-01-25 18:01:18 +01:00
Amaury Denoyelle
71fd03632f MINOR: mux-quic/h3: send SETTINGS as soon as transport is ready
As specified by HTTP3 RFC, SETTINGS frame should be sent as soon as
possible. Before this patch, this was only done on the first qc_send()
invocation. This delay significantly SETTINGS emission until the first
H3 response is ready to be transferred.

This patch fixes this by ensuring SETTINGS is emitted when MUX-QUIC is
being setup.

As a side point, return value of finalize operation is checked. This
means that an error during SETTINGS emission will cause the connection
init to fail.

This should be backported up to 2.7.
2023-01-25 16:01:55 +01:00
Willy Tarreau
35c4dd0005 CLEANUP: stconn: always use se_fl_set_error() to set the pending error
In mux-h2 and mux-quic we still had two places manually setting
SE_FL_ERR_PENDING or SE_FL_ERROR depending on the EOS state, instead
of using se_fl_set_error() which takes care of the condition. Better
use the specialized function for this, it will allow to centralize
the conditions. Note that this will be needed to fix a bug.
2023-01-17 16:25:29 +01:00
Amaury Denoyelle
a9de7ea1dc MINOR: mux-quic: use send-list for immediate sending retry
Sending is done with several iterations over qcs streams in qc_send().
The first loop is conducted over streams in <qcc.send_list>. After this
first iteration, some streams may still have data in their Tx buffer but
were blocked by a full qc_stream_desc buffer. In this case, they have
release their qc_stream_desc buffer in qcc_streams_sent_done().

New iterations can be done for these streams which can allocate new
qc_stream_desc buffer if available. Before this patch, this was done
through another stream list <qcc.send_retry_list>. Now, we can reuse the
new <qcc.send_list> for this usage.

This is safe to use as after first iteration, we have guarantee that
either one of the following is true if there is still streams in
<qcc.send_list> :
* transport layer has rejected data due to congestion
* stream is left because it is blocked on stream flow control
* stream still has data and has released a fulfilled qc_stream_desc
  buffer. Immediate retry is useful for these streams : they will
  allocate a new qc_stream_desc buffer if possible to continue sending.

This must be backported up to 2.7.
2023-01-10 18:09:42 +01:00
Amaury Denoyelle
0a1154afb5 MINOR: mux-quic: use send-list for STOP_SENDING/RESET_STREAM emission
When a STOP_SENDING or RESET_STREAM must be send, its corresponding qcs
is inserted into <qcc.send_list> via qcc_reset_stream() or
qcc_abort_stream_read().

This allows to remove the iteration on full qcs tree in qc_send().
Instead, STOP_SENDING and RESET_STREAM is done in the loop over
<qcc.send_list> as with STREAM frames. This should improve slightly the
performance, most notably when large number of streams are opened.

This must be backported up to 2.7.
2023-01-10 17:49:50 +01:00
Amaury Denoyelle
f9b03265f0 MEDIUM: h3: send SETTINGS before STREAM frames
Complete qcc_send_stream() function to allow to specify if the stream
should be handled in priority. Internally this will insert the qcs
instance in front of <qcc.send_list> to be able to treat it before other
streams.

This functionality is useful when some QUIC streams should be sent
before others. Most notably, this is used to guarantee that H3 SETTINGS
is done first via the control stream.

This must be backported up to 2.7.
2023-01-10 17:49:50 +01:00
Amaury Denoyelle
20f2a425ff MAJOR: mux-quic: rework stream sending priorization
Implement a mechanism to register streams ready to send data in new
STREAM frames. Internally, this is implemented with a new list
<qcc.send_list> which contains qcs instances.

A qcs can be registered safely using the new function qcc_send_stream().
This is done automatically in qc_send_buf() which covers most cases.
Also, application layer is free to use it for internal usage streams.
This is currently the case for H3 control stream with SETTINGS sending.

The main point of this patch is to handle stream sending fairly. This is
in stark contrast with previous code where streams with lower ID were
always prioritized. This could cause other streams to be indefinitely
blocked behind a stream which has a lot of data to transfer. Now,
streams are handled in an order scheduled by se_desc layer.

This commit is the first one of a serie which will bring other
improvments which also relied on the send_list implementation.

This must be backported up to 2.7 when deemed sufficiently stable.
2023-01-10 17:49:50 +01:00
Amaury Denoyelle
31d2057c59 MINOR: mux-quic: add traces for flow-control limit reach
Add new traces when QUIC flow-control limits are reached at stream or
connection level. This may help to explain an interrupted transfer.

This should be backported up to 2.6.
2023-01-10 17:45:41 +01:00
Amaury Denoyelle
ab6cdecd71 BUG/MINOR: mux-quic: fix transfer of empty HTTP response
QUIC stream did not transferred its response if it was an empty HTTP
response without headers nor entity body. This is caused by an
incomplete condition on qc_send() which skips streams with empty
<tx.buf>.

Fix this by extending the condition. Sending will be conducted on a
stream if <tx.buf> is not empty or FIN notification must be provided.
This allows to send the last STREAM frame for this stream.

Such HTTP responses should be extremely rare so this bug is labelled as
MINOR. It was encountered with a HTTP/0.9 request on an empty payload.
The bug was triggered as HTTP/0.9 does not support header in response
message.

Also, note that condition to wakeup MUX tasklet has been changed
similarly in qc_send_buf(). It is not mandatory to work properly
however, most probably because another tasklet_wakeup() is done
before/after.

This should be backported up to 2.6.
2023-01-10 16:44:53 +01:00
Amaury Denoyelle
9107731358 BUG/MINOR: mux-quic: ignore remote unidirectional stream close
Remove ABORT_NOW() on remote unidirectional stream closure. This is
required to ensure our implementation is evolutive enough to not fail on
unknown stream type.

Note that for the moment MAX_STREAMS_UNI flow-control frame is never
emitted. This should be unnecessary for HTTP/3 which have a limited
usage of unidirectional streams but may be required if other application
protocols are supported in the future.

ABORT_NOW() was triggered by s2n-quic which opens an unknown
unidirectional stream with greasing. This was detected by QUIC interop
runner for http3 testcase.

This must be backported up to 2.6.
2022-12-23 00:15:20 +01:00
Amaury Denoyelle
663e872e3a MEDIUM: mux-quic: implement STOP_SENDING emission
Implement STOP_SENDING. This is divided in two main functions :
* qcc_abort_stream_read() which can be used by application protocol to
  request for a STOP_SENDING. This set the flag QC_SF_READ_ABORTED.
* qcs_send_reset() is a static function called after the preceding one.
  It will send a STOP_SENDING via qcc_send().

QC_SF_READ_ABORTED flag is now properly used : if activated on a stream
during qcc_recv(), <qcc.app_ops.decode_qcs> callback is skipped. Also,
abort reading on unknown unidirection remote stream is now fully
supported with the emission of a STOP_SENDING as specified by RFC 9000.

This commit is part of implementing H3 errors at the stream level. This
will allows the H3 layer to request the peer to close its endpoint for
an error on a stream.

This should be backported up to 2.7.
2022-12-22 16:38:16 +01:00
Amaury Denoyelle
5854fc08cc MINOR: mux-quic: handle RESET_STREAM reception
Implement RESET_STREAM reception by mux-quic. On reception, qcs instance
will be mark as remotely closed and its Rx buffer released. The stream
layer will be flagged on error if still attached.

This commit is part of implementing H3 errors at the stream level.
Indeed, on H3 stream errors, STOP_SENDING + RESET_STREAM should be
emitted. The STOP_SENDING will in turn generate a RESET_STREAM by the
remote peer which will be handled thanks to this patch.

This should be backported up to 2.7.
2022-12-22 16:38:04 +01:00
Amaury Denoyelle
bb6296ce06 MINOR: mux-quic: do not count stream flow-control if already closed
It is unnecessary to increase stream credit once its size is known.
Indeed, a peer cannot sent a greater offset than the value advertized.
Else, connection will be closed on STREAM reception with
FINAL_SIZE_ERROR.

This commit is a small optimization and may prevent the emission of
unneeded MAX_STREAM_DATA frames on some occasions.

It should be backported up to 2.7.
2022-12-22 16:29:59 +01:00
Amaury Denoyelle
a473f196f1 MEDIUM: mux-quic: implement shutw
Implement mux_ops shutw operation for QUIC mux. A RESET_STREAM is
emitted unless the stream is already closed due to all data or
RESET_STREAM already transmitted.

This operation is notably useful when upper stream layer wants to close
the connection early due to an error.

This was tested by using a HTTP server which listens with PROXY protocol
support. The corresponding server line on haproxy configuration
deliberately not specify send-proxy. This causes the server to close
abruptly the connection. Without this patch, nothing was done on the QUIC
stream which was kept open until the whole connection is closed. Now, a
proper RESET_STREAM is emitted to report the error.

This should be backported up to 2.7.
2022-12-22 16:22:39 +01:00
Amaury Denoyelle
15337fd808 BUG/MEDIUM: mux-quic: fix double delete from qcc.opening_list
qcs instances for bidirectional streams are inserted in
<qcc.opening_list>. It is removed from the list once a full HTTP request
has been parsed. This is required to implement http-request timeout.

In case a stream is deleted before receiving full HTTP request, it also
must be removed from <qcc.opening_list>. This was not the case on first
implementation but has been fixed by the following patch :
  641a65ff3cccd394eed49378c6ccdb8ba0a101a7
  BUG/MINOR: mux-quic: remove qcs from opening-list on free

This means that now a stream can be deleted from the list in two
different functions. Sadly, as LIST_DELETE was used in both cases,
nothing prevented a double-deletion from the list, even though
LIST_INLIST was used. Both calls are replaced with LIST_DEL_INIT which
is idempotent.

This bug causes memory corruption which results in most cases in a
segfault, most of times outside of mux-quic code itself. It has been
found first by gabrieltz who reported it on the github issue #1903. Big
thanks to him for his testing.

This bug also causes failures on several 'M' transfer testcase of QUIC
interop-runner. The s2n-quic client is particularly useful in this case
as segfaults triggers were most of the times on the LIST_DELETE
operation itself. This is probably due to its encapsulating of HEADERS
frame with fin bit delayed in a following empty STREAM frame.

This must be backported wherever the above patch is, up to 2.6.
2022-12-21 08:58:04 +01:00
Amaury Denoyelle
4b167006fd BUG/MINOR: mux-quic: handle properly alloc error in qcs_new()
Use qcs_free() on allocation failure in qcs_new() This ensures that all
qcs content is properly deallocated and prevent memleaks. Most notably,
qcs instance is now removed from qcc tree.

This bug is labelled as MINOR as it occurs only on qcs allocation
failure due to memory exhaustion.

This must be backported up to 2.6.
2022-12-12 14:54:39 +01:00
Amaury Denoyelle
641a65ff3c BUG/MINOR: mux-quic: remove qcs from opening-list on free
qcs instances for bidirectional streams are inserted in
<qcc.opening_list>. It is removed from the list once a full HTTP request
has been parsed. This is required to implement http-request timeout.

If a qcs instance is freed before receiving a full HTTP request, it must
be removed from the <qcc.opening_list>. Else a segfault will occur in
qcc_refresh_timeout() when accessing a dangling pointer.

For the moment this bug was not reproduced in production. This is
because there exists only few rare cases where a qcs is freed before
HTTP request parsing. However, as error detection will be improved on
H3, this will occur more frequently in the near future.

This must be backported up to 2.6.
2022-12-12 14:54:39 +01:00
Amaury Denoyelle
6eb3c4b71c CLEANUP: mux-quic: remove unused attribute on qcs_is_close_remote()
qcs_is_close_remote() is used in qcc_decode_qcs(). Thus the unused
function attribute is now unneeded.

This can be backported up to 2.7.
2022-12-12 14:54:39 +01:00
Amaury Denoyelle
b7ce79c814 MINOR: mux-quic: rename duplicate function names
qc_rcv_buf and qc_snd_buf are names used for static functions in both
quic-sock and quic-mux. To remove this ambiguity, slightly modify names
used in MUX code.

In the future, we should properly define a unique prefix for all QUIC
MUX functions to avoid such problem in the future.

This change is part of quic-conn owned socket implementation.
It may be backported to 2.7 after a period of observation.
2022-12-02 14:45:43 +01:00
Amaury Denoyelle
bbb1c68508 BUG/MINOR: quic: fix subscribe operation
Subscribing was not properly designed between quic-conn and quic MUX
layers. Align this as with in other haproxy components : <subs> field is
moved from the MUX to the quic-conn structure. All mention of qcc MUX is
cleaned up in quic_conn_subscribe()/quic_conn_unsubscribe().

Thanks to this change, ACK reception notification has been simplified.
It's now unnecessary to check for the MUX existence before waking it.
Instead, if <subs> quic-conn field is set, just wake-up the upper layer
tasklet without mentionning MUX. This should probably be extended to
other part in quic-conn code.

This should be backported up to 2.6.
2022-10-26 18:18:26 +02:00
Amaury Denoyelle
0aba11e9e7 MINOR: quic: remove unnecessary quic_session_accept()
A specialized listener accept was previously used for QUIC. This is now
unneeded and we can revert to the default one session_accept_fd().

One change of importance is that the call order between
conn_xprt_start() and conn_complete_session() is now reverted to the
default one. This means that MUX instance is now NULL during
qc_xprt_start() and its app-ops layer cannot be set here. This operation
has been delayed to qc_init() to prevent a segfault.

This should be backported up to 2.6.
2022-10-26 18:16:20 +02:00
Amaury Denoyelle
176174f7e4 BUG/MINOR: mux-quic: complete flow-control for uni streams
Max stream data was not enforced and respect for local/remote uni
streams. Previously, qcs instances incorrectly reused the limit defined
from bidirectional ones.

This is now fixed. Two fields are added in qcc structure connection :
* value for local flow control to enforce on remote uni streams
* value for remote flow control to respect on local uni streams

These two values can be reused to properly initialized msd field of a
qcs instance in qcs_new(). The rest of the code is similar.

This must be backported up to 2.6.
2022-10-21 17:31:18 +02:00
Amaury Denoyelle
036cc5d880 MINOR: mux-quic: check quic-conn return code on Tx
Inspect return code of qc_send_mux(). If quic-conn layer reports an
error, this will interrupt the current emission process.

This should be backported up to 2.6.
2022-10-05 11:08:32 +02:00
Amaury Denoyelle
d7755375a5 BUG/MINOR: mux-quic: ignore STOP_SENDING for locally closed stream
It is possible to receive a STOP_SENDING frame for a locally closed
stream. This was not properly managed as this would result in a BUG_ON()
crash from qcs_idle_open() call under qcc_recv_stop_sending().

Now, STOP_SENDING frames are ignored when received on streams already
locally closed. This has two consequences depending on the reason of
closure :

* if a RESET_STREAM was already emitted and closed the stream, this
  patch prevents to emit a new RESET_STREAM. This behavior is thus
  better.

* if stream was closed due to all data transmitted, no RESET_STREAM will
  be built. This is contrary to the RFC 9000 which advice to transmit
  it, even on "Data Sent" state. However, this is not mandatory so the
  new behavior is acceptable, even if it could be improved.

This crash has been detected on haproxy.org. This can be artifically
reproduced by adding the following snippet at the end of qc_send_mux()
when doing a request with a small payload response :
  qcc_recv_stop_sending(qc->qcc, 0, 0);

This must be backported up to 2.6.
2022-10-03 17:20:31 +02:00
Amaury Denoyelle
92fa63f735 CLEANUP: quic: create a dedicated quic_conn module
xprt_quic module was too large and did not reflect the true architecture
by contrast to the other protocols in haproxy.

Extract code related to XPRT layer and keep it under xprt_quic module.
This code should only contains a simple API to communicate between QUIC
lower layer and connection/MUX.

The vast majority of the code has been moved into a new module named
quic_conn. This module is responsible to the implementation of QUIC
lower layer. Conceptually, it overlaps with TCP kernel implementation
when comparing QUIC and HTTP1/2 stacks of haproxy.

This should be backported up to 2.6.
2022-10-03 16:25:17 +02:00
Amaury Denoyelle
0ed617ac2f BUG/MEDIUM: mux-quic: properly trim HTX buffer on snd_buf reset
MUX QUIC snd_buf operation whill return early if a qcs instance is
resetted. In this case, HTX is left untouched and the callback returns
the whole bufer size. This lead to an undefined behavior as the stream
layer is notified about a transfer but does not see its HTX buffer
emptied. In the end, the transfer may stall which will lead to a leak on
session.

To fix this, HTX buffer is now resetted when snd_buf is short-circuited.
This should fix the issue as now the stream layer can continue the
transfer until its completion.

This patch has already been tested by Tristan and is reported to solve
the github issue #1801.

This should be backported up to 2.6.
2022-09-20 15:35:33 +02:00
Amaury Denoyelle
9534e59bb9 MINOR: mux-quic: refactor snd_buf
Factorize common code between h3 and hq-interop snd_buf operation. This
is inserted in MUX QUIC snd_buf own callback.

The h3/hq-interop API has been adjusted to directly receive a HTX
message instead of a plain buf. This led to extracting part of MUX QUIC
snd_buf in qmux_http module.

This should be backported up to 2.6.
2022-09-20 15:35:29 +02:00
Amaury Denoyelle
d80fbcaca2 REORG: mux-quic: export HTTP related function in a dedicated file
Extract function dealing with HTX outside of MUX QUIC. For the moment,
only rcv_buf stream operation is concerned.

The main objective is to be able to support both TCP and HTTP proxy mode
with a common base and add specialized modules on top of it.

This should be backported up to 2.6.
2022-09-20 15:35:23 +02:00
Amaury Denoyelle
36d50bff22 REORG: mux-quic: extract traces in a dedicated source file
QUIC MUX implements several APIs to interface with stream, quic-conn and
app-ops layers. It is planified to better separate this roles, possibly
by using several files.

The first step is to extract QUIC MUX traces in a dedicated source
files. This will allow to reuse traces in multiple files.

The main objective is to be
able to support both TCP and HTTP proxy mode with a common base and add
specialized modules on top of it.

This should be backported up to 2.6.
2022-09-20 15:35:09 +02:00
Amaury Denoyelle
3dc4e5a5b9 BUG/MINOR: mux-quic: do not keep detached qcs with empty Tx buffers
A qcs instance free may be postponed in stream detach operation if the
stream is not locally closed. This condition is there to achieve
transfering data still present in Tx buffer. Once all data have been
emitted to quic-conn layer, qcs instance can be released.

However, the stream is only closed locally if HTX EOM has been seen or
it has been resetted. In case the transfer finished without EOM, a
detached qcs won't be freed even if there is no more activity on it.

This bug was not reproduced but was found on code analysis. Its precise
impact is unknown but it should not cause any leak as all qcs instances
are freed with its parent qcc connection : this should eventually happen
on MUX timeout or QUIC idle timeout.

To adjust this, condition to mark a stream as locally closed has been
extended. On qcc_streams_sent_done() notification, if its Tx buffer has
been fully transmitted, it will be closed if either FIN STREAM was set
or the stream is detached.

This must be backported up to 2.6.
2022-09-20 10:46:59 +02:00
Amaury Denoyelle
afb7b9d8e5 BUG/MEDIUM: mux-quic: fix nb_hreq decrement
nb_hreq is a counter on qcc for active HTTP requests. It is incremented
for each qcs where a full HTTP request was received. It is decremented
when the stream is closed locally :
- on HTTP response fully transmitted
- on stream reset

A bug will occur if a stream is resetted without having processed a full
HTTP request. nb_hreq will be decremented whereas it was not
incremented. This will lead to a crash when building with
DEBUG_STRICT=2. If BUG_ON_HOT are not active, nb_hreq counter will wrap
which may break the timeout logic for the connection.

This bug was triggered on haproxy.org. It can be reproduced by
simulating the reception of a STOP_SENDING frame instead of a STREAM one
by patching qc_handle_strm_frm() :

+       if (quic_stream_is_bidi(strm_frm->id))
+               qcc_recv_stop_sending(qc->qcc, strm_frm->id, 0);
+       //ret = qcc_recv(qc->qcc, strm_frm->id, strm_frm->len,
+       //               strm_frm->offset.key, strm_frm->fin,
+       //               (char *)strm_frm->data);

To fix this bug, a qcs is now flagged with a new QC_SF_HREQ_RECV. This
is set when the full HTTP request is received. When the stream is closed
locally, nb_hreq will be decremented only if this flag was set.

This must be backported up to 2.6.
2022-09-19 12:12:21 +02:00
cui fliter
a94bedc0de CLEANUP: quic,ssl: fix tiny typos in C comments
This fixes 4 tiny and harmless typos in mux_quic.c, quic_tls.c and
ssl_sock.c. Originally sent via GitHub PR #1843.

Signed-off-by: cui fliter <imcusg@gmail.com>
[Tim: Rephrased the commit message]
[wt: further complete the commit message]
2022-09-17 10:59:59 +02:00