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15 commits

Author SHA1 Message Date
Victor Boivie
3c6b46fc16 Reland "dcsctp: Support zero checksum packets"
This reverts commit 45eae34693.

It was found not to be the root cause of the performance
regression, so it's safe to reland.

Bug: webrtc:14997
Change-Id: I67c90752875bf4071cbdd5adfa462a37f4d4ceab
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/302162
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#39910}
2023-04-20 20:32:01 +00:00
Victor Boivie
45eae34693 Revert "dcsctp: Support zero checksum packets"
This reverts commit bd46bb7660.

Reason for revert: There is a slight performance degradation
pointing to this CL, so revert this to be able to confirm if
it is the culprit.


Original change's description:
> dcsctp: Support zero checksum packets
>
> If configured, the packet parser will allow packets with
> a set checksum of zero. In that case, the correct checksum
> will not even be calculated, avoiding a CPU intensive
> calculation.
>
> Also, if specified when building a packet, the checksum can
> be opted to be not calculated and written to the packet.
> This is to be used when draft-tuexen-tsvwg-sctp-zero-checksum
> has been negotiated, except for some packets during association
> establishment.
>
> This is mainly a preparation CL and follow-up CL will enable
> this feature.
>
> Low-Coverage-Reason: Affects debug logging code not run in tests
> Bug: webrtc:14997
> Change-Id: I3207ac3a626df039ee2990403c2edd6429f17617
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/298481
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Commit-Queue: Victor Boivie <boivie@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#39737}

Bug: webrtc:14997
Change-Id: Ie22267abb4bcd25d5af07875eb933c51ed5be853
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/301580
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39878}
2023-04-17 19:29:55 +00:00
Victor Boivie
bd46bb7660 dcsctp: Support zero checksum packets
If configured, the packet parser will allow packets with
a set checksum of zero. In that case, the correct checksum
will not even be calculated, avoiding a CPU intensive
calculation.

Also, if specified when building a packet, the checksum can
be opted to be not calculated and written to the packet.
This is to be used when draft-tuexen-tsvwg-sctp-zero-checksum
has been negotiated, except for some packets during association
establishment.

This is mainly a preparation CL and follow-up CL will enable
this feature.

Low-Coverage-Reason: Affects debug logging code not run in tests
Bug: webrtc:14997
Change-Id: I3207ac3a626df039ee2990403c2edd6429f17617
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/298481
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39737}
2023-04-02 21:38:00 +00:00
Victor Boivie
5625a86f5a dcsctp: Handle re-received stream reset requests
When re-receiving a stream reset request with the same request
sequence number, reply with the same result as previous time. In
case the original request was deferred, and "in progress" was
replied, it's important to not indicate that it was performed
successfully as that will make the sender believe it has completed
before it did.

Bug: webrtc:14277
Change-Id: I5c7082dc285180d62061d7ebebe05566e5c4195c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/274080
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38012}
2022-09-05 11:56:10 +00:00
Victor Boivie
c8680c5dc6 dcsctp: Generate lifecycle events
This adds the final piece, which makes the socket and the retransmission
queue generate the callbacks.

Bug: webrtc:5696
Change-Id: I1e28c98e9660bd018e817a3ba0fa6b03940fcd33
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264125
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37455}
2022-07-06 08:04:15 +00:00
Victor Boivie
2cffde72b8 dcsctp: Restore from handover as separate methods
Before this CL, some components, e.g. the SendQueue, was first created
and then later restored from handover state, while some were created from
the handover state, as an optional parameter to their constructors.

This CL will make it consistent, by always creating the components in a
pristine state, and then modifying it when restoring them from handover
state. The name "RestoreFromState" was used to be consistent with SendQueue
and the socket.

This is just refactoring.

Bug: None
Change-Id: Ifad2d2e84a74a12a93abbfb0fe1027ebb9580e73
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/267006
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37384}
2022-06-30 22:09:04 +00:00
Victor Boivie
8c72cc1634 dcsctp: Handle in-progress stream sequence numbers
When an outgoing stream reset is sent, with sequence number A, and the
receiver can't perform it immediately, it will return IN_PROGRESS with
response sequence number A.

This is then retried with sequence number A+1, and the peer would then
possibly respond PERFORMED with response sequence number A+1.

Before this CL, whenever a request was sent that didn't immediately
succeed, it wouldn't increment its expected response sequence number.
So in the retry above, the socket would still expect the response
sequence number to stay at A, not at A+1.

Bug: webrtc:13994
Change-Id: I6f36d45229a7fb312e97ad15826e0377f4efb64f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/261310
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36797}
2022-05-06 12:20:42 +00:00
Victor Boivie
d7fd0f9744 dcsctp: Handle rapid closing of streams
When streams were to be reset, but there was already an ongoing
stream reset command in-flight, those streams wouldn't be properly
reset. When multiple streams were reset close to each other (within
an RTT), some streams would not have their SSNs reset, which resulted
in the stream resuming the SSN sequence. This could result in ordered
streams not delivering all messages as the receiver wouldn't deliver any
messages with SSN different from the expected SSN=0.

In WebRTC data channels, this would be triggered if multiple channels
were closed at roughly the same time, then re-opened, and continued
to be used in ordered mode. Unordered messages would still be delivered,
but the stream state could be wrong as the DATA_CHANNEL_ACK message is
sent ordered, and possibly not delivered.

There were unit tests for this, but not on the socket level using
real components, but just on the stream reset handler using mocks,
where this issue wasn't found. Also, those mocks didn't validate that
the correct parameters were provided, so that's fixed now.

The root cause was the PrepareResetStreams was only called if there
wasn't an ongoing stream reset operation in progress. One may try to
solve it by always calling PrepareResetStreams also when there is an
ongoing request, or to call it when the request has finished. One would
then realize that when the response of the outgoing stream request is
received, and CommitResetStreams is called, it would reset all paused
and (prepared) to-be-reset streams - not just the ones in the outgoing
stream request.

One cause of this was the lack of a single source of truth of the stream
states. The SendQueue kept track of which streams that were paused, but
the stream reset handler kept track of which streams that were
resetting. As that's error prone, this CL moves the source of truth
completely to the SendQueue and defining explicit stream pause states. A
stream can be in one of these possible states:

  * Not paused. This is the default for an active stream.
  * Pending to be paused. This is when it's about to be reset, but
    there is a message that has been partly sent, with fragments
    remaining to be sent before it can be paused.
  * Paused, with no partly sent message. In this state, it's ready to
    be reset.
  * Resetting. A stream transitions into this state when it has been
    paused and has been included in an outgoing stream reset request.
    When this request has been responded to, the stream can really be
    reset (SSN=0, MID=0).

This CL also improves logging, and adds socket tests to catch this
issue.

Bug: webrtc:13994, chromium:1320194
Change-Id: I883570d1f277bc01e52b1afad62d6be2aca930a2
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/261180
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36771}
2022-05-05 07:30:58 +00:00
Henrik Boström
b951dc6f4c Allow specifying delayed task precision of dcsctp::Timer.
Context: The timer precision of PostDelayedTask() is about to be lowered
to include up to 17 ms leeway. In order not to break use cases that
require high precision timers, PostDelayedHighPrecisionTask() will
continue to have the same precision that PostDelayedTask() has today.
webrtc::TaskQueueBase has an enum (kLow, kHigh) to decide which
precision to use when calling PostDelayedTaskWithPrecision().

See go/postdelayedtask-precision-in-webrtc for motivation and a table of
delayed task use cases in WebRTC that are "high" or "low" precision.

Most timers in DCSCTP are believed to only be needing low precision (see
table), but the delayed_ack_timer_ of DataTracker[1] is an example of a
use case that is likely to break if the timer precision is lowered (if
ACK is sent too late, retransmissions may occur). So this is considered
a high precision use case.

This CL makes it possible to specify the precision of dcsctp::Timer.
In a follow-up CL we will update delayed_ack_timer_ to kHigh precision.

[1] https://source.chromium.org/chromium/chromium/src/+/main:third_party/webrtc/net/dcsctp/rx/data_tracker.cc;l=340

Bug: webrtc:13604
Change-Id: I8eec5ce37044096978b5dd1985fbb00bc0d8fb7e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/249081
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35809}
2022-01-26 18:40:24 +00:00
Sergey Sukhanov
3852698ad9 dcsctp: support handover state serialization testing
dcSCTP library users can set their custom
g_handover_state_transformer_for_test that can serialize and
deserialize the state. All dcSCTP handover tests call
g_handover_state_transformer_for_test. If some part of the state is
serialized incorrectly or is forgotten, high chance that it will
fail the tests.

Bug: webrtc:13154
Change-Id: I251a099be04dda7611e9df868d36e3a76dc7d1e1
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/232325
Commit-Queue: Sergey Sukhanov <sergeysu@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35035}
2021-09-20 10:08:58 +00:00
Sergey Sukhanov
3b08fe3dcd dssctp: support socket handover in StreamResetHandler
Bug: webrtc:13154
Change-Id: Idafbed4f3c1af8d0cca833ba983c4b4b99118335
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/232121
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Sergey Sukhanov <sergeysu@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35012}
2021-09-16 11:33:21 +00:00
Victor Boivie
8df32eb0e1 dcsctp: Add API to indicate packet send status
Before this change, there was no way for a client to indicate to the
dcSCTP library if a packet that was supposed to be sent, was actually
sent. It was assumed that it always was.

To handle temporary failures better, such as retrying to send packets
that failed to be sent when the send buffer was full, this information
is propagated to the library.

Note that this change only covers the API and adaptations to clients.
The actual implementation to make use of this information is done as a
follow-up change.

Bug: webrtc:12943
Change-Id: I8f9c62e17f1de1566fa6b0f13a57a3db9f4e7684
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/228563
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34767}
2021-08-16 11:29:47 +00:00
Victor Boivie
236ac50628 dcsctp: Add public API for BufferedAmountLow
This adds native support for the RTCDataChannel properties:
https://developer.mozilla.org/en-US/docs/Web/API/RTCDataChannel/bufferedAmount
https://developer.mozilla.org/en-US/docs/Web/API/RTCDataChannel/bufferedAmountLowThreshold

And the RTCDataChannel event:
https://developer.mozilla.org/en-US/docs/Web/API/RTCDataChannel/onbufferedamountlow

The old callback, NotifyOutgoingMessageBufferEmpty, is deprecated as it
didn't work very well. It will not be triggered and will be removed
as soon as all users of it are gone. There is a new callback,
OnTotalBufferedAmountLow, that serves the same purpose but also allows
setting an arbitrary limit when it should be triggered (See
DcSctpOptions::total_buffered_amount_low_threshold).

Bug: webrtc:12794
Change-Id: Ic1c92f174eff8a1acda0b5fd3dcc45bd1cfa2704
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/219691
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34144}
2021-05-27 15:27:27 +00:00
Victor Boivie
1d2fa9a1c3 dcsctp: Expire timers just before triggering them
In real life, when a Timeout expires, the caller is supposed to call
DcSctpSocket::HandleTimeout directly, as the Timeout that just expired
is stopped (it just expired), but the Timer still believes it's running.
The system is not in a consistent state.

In tests, all timeouts were evaluated at the same time, which, if two
timeouts expired at the same time, would put them both as "not running",
and with their timers believing they were running. So if you would do
any operation on a timer whose timeout had just expired, the timeout
would assert saying that "you can't stop a stopped timeout" or similar.

This isn't relevant in non-test scenarios.

Solved by expiring timeouts one by one.

Bug: webrtc:12614
Change-Id: I79d006f4d3e96854d77cec3eb0080aa23b8569cb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/217560
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33925}
2021-05-05 12:40:21 +00:00
Victor Boivie
322f911c10 dcsctp: Add Stream Reset Handler
The Stream Reset handler handles a limited subset of RFC6525, but all
the parts necessary to implement "Closing a Data Channel", which is done
by sending an Outgoing SSN Reset Request.

There can only be a single "Stream Reconfiguration Request" on the wire
at any time, so requests are queued and sent when a previous request -
if any - finishes. Resetting a stream is an asynchronous operation and
the receiver will not perform the stream resetting until it can be done,
which is when the currently partly received message has been fully
received. And the sender will not send a request until the currently
fragmented message (on that stream) is still sent.

There are numerous callbacks to make the client know what's really
happening as these callbacks will result in Data Channel events.

Bug: webrtc:12614
Change-Id: I9fd0a94713f0c1fc384d1189f3894e87687408b7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/214131
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Tommi <tommi@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33856}
2021-04-27 21:08:56 +00:00