Commit graph

138 commits

Author SHA1 Message Date
Per K
569849e885 Move call/simulated_network to test/network
Old target and call/simulated.h exist but refer to new target in test/network.

Bug: webrtc:14525
Change-Id: Ida04cef17913f2f829d7e925ae454dc40d5e8240
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/349264
Commit-Queue: Per Kjellander <perkj@webrtc.org>
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Owners-Override: Per Kjellander <perkj@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#42191}
2024-04-29 09:55:06 +00:00
Victor Boivie
de276cf049 dcsctp: Remove initial TSN from reassembly queue
With a previous refactoring, which made the data tracker responsible for
ensuring that the reassembly queue doesn't see any duplicate received
chunks, it no longer needs to know the initial peer's TSN. Removing.

Bug: None
Change-Id: I0e2aef1de0293f1860b46dee0089757c9c300aea
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/345701
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41997}
2024-04-04 19:19:47 +00:00
Victor Boivie
2fc097ea83 Reapply "dcsctp: Add per-stream-limit, refactor limits."
Keeping the old setting for the total queue size
limit, which avoids breaking a downstream.

This reverts commit 47ce449afa
and relands commit 4c990e2e56.

Bug: chromium:40072842
Change-Id: I1e7d14b5d0026232d1fc9277172b6947b8be3490
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/343120
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41907}
2024-03-15 13:27:37 +00:00
Björn Terelius
47ce449afa Revert "dcsctp: Add per-stream-limit, refactor limits."
This reverts commit 4c990e2e56.

Reason for revert: Breaks downstream build.

Original change's description:
> dcsctp: Add per-stream-limit, refactor limits.
>
> The limits have been moved out from the Send Queue as they were enforced
> outside the queue anyway (in the socket). That was a preparation for
> adding even more limits; There is now also a per-stream limit, allowing
> individual streams to have one (global) limit, and the entire socket to
> have another limit.
>
> These limits are very small in the default options. In Chrome, the limit
> is 16MB per stream, so expect the defaults to be updated when the
> additional buffering outside dcSCTP is removed.
>
> Bug: chromium:41221056
> Change-Id: I9f835be05d349cbfce3e9235d34b5ea0e2fe87d1
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/342481
> Reviewed-by: Florent Castelli <orphis@webrtc.org>
> Commit-Queue: Victor Boivie <boivie@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#41895}

Bug: chromium:41221056
Change-Id: Icd57fbfca87d6b512cfc7f7682ae709000c2bcad
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/343080
Commit-Queue: Björn Terelius <terelius@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#41901}
2024-03-14 16:47:45 +00:00
Victor Boivie
4c990e2e56 dcsctp: Add per-stream-limit, refactor limits.
The limits have been moved out from the Send Queue as they were enforced
outside the queue anyway (in the socket). That was a preparation for
adding even more limits; There is now also a per-stream limit, allowing
individual streams to have one (global) limit, and the entire socket to
have another limit.

These limits are very small in the default options. In Chrome, the limit
is 16MB per stream, so expect the defaults to be updated when the
additional buffering outside dcSCTP is removed.

Bug: chromium:41221056
Change-Id: I9f835be05d349cbfce3e9235d34b5ea0e2fe87d1
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/342481
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41895}
2024-03-13 11:13:56 +00:00
Victor Boivie
2bfb5db548 dcsctp: Update zero checksum option to v-06 draft
https://datatracker.ietf.org/doc/draft-ietf-tsvwg-sctp-zero-checksum/06/

The previous implementation was for version 00, and since then changes
have been made. The chunk that is used to negotiate this capability has
now grown to include an additional property - the sender's alternate
error detection method.

Bug: webrtc:14997
Change-Id: I78043d187b79f40bbadbcba02eae6eedf54f30f9
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/336380
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41759}
2024-02-19 10:25:17 +00:00
Victor Boivie
6791c9d17e dcsctp: Relax thread sequence checker
The DcSctpSocket is thread compatible. As long as you serialize accesses
to it - either by calling it from the same thread, or using some kind of
concurrency primitive (e.g. mutex) to avoid calling the API methods from
different threads concurrently, it's fine.

Using the sequence checker, we can verify that the socket is called from
the thread it was created on, or from the same task queue. This provided
a more strict verification, as it didn't allow e.g. creating a socket on
one thread, and then handing it to a different thread where it was used.
Nor did it allow having multiple threads use it, protecting any calls to
it using an external mutex.

One can avoid these checks using webrtc::CurrentTaskQueueSetter to allow
the sequence checker to believe it's running where it's not running, but
this is a hack.

This CL removes the sequence checker in the socket, to simplify using it
in environments that don't use task queues for synchronization. Since it
is still kept in dcsctp::TaskQueueTimeoutFactory, it's still used in all
environments where the task queue is used (e.g. Chrome).

This makes it easier to use dcSCTP without WebRTC.

Bug: None
Change-Id: I2674d7cd902bad45ed3d0816c908ecf3ee971727
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/333801
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41482}
2024-01-09 11:50:44 +00:00
Daniel Collins
c9d44b3fb9 Add SendMany method to dcsctp socket
Bug: webrtc:15724
Change-Id: Ib1689cd46395e2315803714ef50c009580fd71bb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/331021
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41397}
2023-12-15 21:35:14 +00:00
Daniel Collins
d093d0db7f Change CallbackDeferrer to pre-reserve the deferred vector.
The push_back pattern results in frequent vector growth which has performance overhead. This is .5% of our server's CPU

Bug: webrtc:15723
Change-Id: Ic151c81a4b49a7d48a354b75f62694bc6f9a1ee4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/331440
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Daniel Collins <dpcollins@google.com>
Cr-Commit-Position: refs/heads/main@{#41388}
2023-12-14 21:08:58 +00:00
Daniel Collins
f418f48702 Change CallbackDeferrer to use a variant and callback pointer instead of std::function
This should substantially reduce the overhead due to deferred callbacks in profiles.

Bug: webrtc:15723
Change-Id: I4c52beb91eb08c9b0ac2d1ce9a4e11839aa35e38
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/331020
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Daniel Collins <dpcollins@google.com>
Cr-Commit-Position: refs/heads/main@{#41363}
2023-12-12 13:15:12 +00:00
Victor Boivie
63e273ad4b dcsctp: Persist all state in state cookie
In the example below, the association is being established between peer
A and Z, and A is the initiating party.

Before this CL, when an association was about to be established, Z would
after having received the INIT chunk, persist state in the socket about
which verification tag and initial TSN that was picked. These would be
re-generated on every incoming INIT (that's fine), but when A had
extracted the cookie from INIT_ACK and sent a reply (COOKIE_ECHO) with
the state cookie, that could fail validation when it's received by Z, if
the sent cookie was not the most recent one or if the COOKIE_ECHO had a
verification tag coming not from the most recent INIT_ACK, because Z had
replaced the state in the socket with the one generated when the second
INIT_ACK chunk was generated - state it used for validation of future
received data.

In other words:
A -> INIT 1
<timeout>
A -> INIT 2 (retransmission of INIT 1)
INIT 1 -> Z - sends INIT_ACK 1 with verification_tag=1, initial_tsn=1,
              cookie 1 (and records these to socket state)
INIT 2 -> Z - sends INIT_ACK 2 with verification_tag=2, initial_tsn=2,
              cookie 2 (replaces socket state with the new data)
INIT_ACK 1 -> A -> sends COOKIE_ECHO with verification_tag=1, cookie 1
COOKIE_ECHO (cookie 1) -> Z <FAILS, as the state isn't as expected>.

The solution is really to do what RFC4960 says, to not maintain any
state as the receiving peer until COOKIE_ECHO has been received. This
was initially not done because the underlying reason why this is
important in SCTP is to avoid denial of service, and this is why SCTP
has the four-way handshake. But for Data Channels - SCTP over DTLS -
this attack vector isn't available. So the implementation was
"simplified" by keeping socket state instead of encoding it in the
state cookie, but that obviously had downsides.

So with this CL, the non-initiating peer in connection establishment
doesn't keep any socket state, and puts all that state in the state
cookie instead. This allows any COOKIE_ECHO to be received by Z.

Bug: webrtc:15712
Change-Id: I596c7330ce27292612d3c9f86b21c712f6f4e408
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/330440
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41340}
2023-12-08 10:54:42 +00:00
Victor Boivie
9a2e32b9f2 dcsctp: Rename outstanding bytes to unacked bytes
And the same for outstanding items, which become unacked items. The old
names were unfortunate - especially since they were managed by a class
called OutstandingData.

To make this less complicated, these variables have been renamed to
something that is easier to understand; "Unacked bytes/items". Simply
what has been sent but hasn't been acked or nacked yet. So likely what's
in-flight, but could possibly be lost and not found to be lost yet.

Bug: None
Change-Id: I877d7f2cac5d164bf2f9f66cb32ae1f6d850ad2c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/329761
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41313}
2023-12-04 19:10:17 +00:00
Sergey Silkin
ebc4d3edd5 Move StrJoin to rtc_base/strings
A similar function was defined in rtc_base/openssl_adapter. Moving it from net/dcsctp/common/ to rtc_base/strings/. I'm planning to use StrJoin in a video codec test (a follow-up change).

Bug: webrtc:14852
Change-Id: Ie657c03e7f9fb52c189c127af6f66ec505b512ae
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/327322
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41166}
2023-11-15 12:10:28 +00:00
Victor Boivie
82cbbcc179 dcsctp: Convert use of TimeMs to webrtc::Timestamp
While this is a fairly big CL, it's fairly straightforward. It replaces
uses of TimeMs with webrtc::Timestamp, and additionally does some
cleanup of DurationMs to webrtc::TimeDelta that are now easier to do.

Bug: webrtc:15593
Change-Id: Id0e3edcba0533e0e8df3358b1778b6995c344243
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/326560
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41138}
2023-11-12 21:12:29 +00:00
Victor Boivie
2d43ab8508 dcsctp: Add Now() callback
This callback is identical to TimeMillis, but returns a
webrtc::Timestamp instead of a TimeMs.

When all callers have migrated to Now() (and all dcsctp code),
TimeMillis will be removed.

Bug: webrtc:15593
Change-Id: I608387607537f29989736af5bf98c7f184f52ebc
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/326500
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41127}
2023-11-10 15:23:13 +00:00
Victor Boivie
4397482d71 dcsctp: Convert timers to rtc::TimeDelta
With this, the code base should be mostly converted from using
DurationMs to rtc::TimeDelta, and the work can continue to replace
TimeMs with rtc::Timestamp.

Bug: webrtc:15593
Change-Id: I083fee6eccb173efc0232bb8d46e2554a5fbee5b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/326161
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41101}
2023-11-07 21:42:15 +00:00
Victor Boivie
be04c98d64 dcsctp: Migrate non-Timer related to rtc::TimeDelta
This does the bulk of the remaining refactoring, except timers since
they are an even bigger part - but more isolated.

Bug: webrtc:15593
Change-Id: I7afa349e2119be7592797ee6b3b198e6de4f697a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/326160
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41090}
2023-11-06 19:55:22 +00:00
Victor Boivie
37f5172f6e dcsctp: Use TimeDelta in RetransmissionTimeout
It's still doing the calculations in milliseconds, which will be updated
in follow-up CLs.

Bug: webrtc:15593
Change-Id: I7fb93d4687d58f409db182db40db720d82feb3dd
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325524
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41074}
2023-11-03 11:56:18 +00:00
Harald Alvestrand
78f905e5cc Move some users to use webrtc::RefCountInterface
Bug: webrtc:15622
Change-Id: I2d4c20c726af1a052e161b7689a73d1e5e3eb191
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325526
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41067}
2023-11-02 14:45:57 +00:00
Victor Boivie
b78e6a9305 dcsctp: Use TimeDelta in TX path
This commit replaces the internal use of DurationMs, with millisecond
precision, to webrtc::TimeDelta, which uses microsecond precision.

This is just a refactoring. The only change to the public API is
convenience methods to convert between DurationMs and webrtc::TimeDelta.

Bug: webrtc:15593
Change-Id: Ida861bf585c716be5f898d0e7ef98da2c15268b7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325402
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41062}
2023-11-01 16:17:13 +00:00
Victor Boivie
51b93a5417 dcsctp: Simplify interface for unchanged timeout
When a timer expires, it can optionally return a new expiration value.
Clearly, that value can't be zero, as that would make it expire
immediately again.

To simplify the interface, and make it easier to migrate to
rtc::TimeDelta, change it from an optional value to an always-present
value that - if zero - means that the expiration time should be
unchanged.

This is just an internal refactoring, and not part of any external
interface.

Bug: webrtc:15593
Change-Id: I6e7010d2dbe774ccb260e14fd6b9861c319e2411
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325281
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41045}
2023-10-31 09:44:39 +00:00
Victor Boivie
f3e9db9e17 dcsctp: Use InfiniteDuration for no max duration
Before this change, a timer could have an optional max duration. Either
that value was present, and that limited the max duration of the timer,
or it was absl::nullopt, which represented "no limit".

To simplify the interface, this CL makes that value "not optional" by
having it always present. The previous "no limit" is now represented by
DurationMs::InfiniteDuration.

This is just a refactoring of internal interfaces - public interfaces
are left untouched.

Bug: webrtc:15593
Change-Id: I80df1d9b2f4d208411ce6cb5045db0a57865e3b4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325280
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41040}
2023-10-30 13:43:07 +00:00
Victor Boivie
b847a43488 dcsctp: Reset synchronously with incoming request
When a sender has requested a stream to be reset, and the last sender
assigned TSN hasn't been received yet, the receiver will enter deferred
reset mode, where it will store any data chunks received after that
given TSN, and replay those later, when the stream has been reset.

Before this CL, leaving deferred mode was done as soon as the sender's
last assigned TSN was received. That's actually not how the RFC
describes the process[1], but was done that way to properly handle some
sequences of RE-CONFIG and FORWARD-TSN. But after having read the RFCs
again, and realizing that whenever RFC6525 mention "any data arriving",
this also applies to any FORWARD-TSN[2] - it's better to reset streams
synchronously with the incoming requests, and defer not just DATA past
the sender last assigned TSN, but also any FORWARD-TSN after that TSN.

This mostly simplifies the code and is mostly a refactoring, but most
importantly aligns it with how the resetting procedure is explained in
the RFC. It also fixes two bugs:

 * It defers FORWARD-TSN *as well as* DATA chunks with a TSN later
   than the sender's last assigned TSN - see test case. The old
   implementation tried to handle that by exiting the deferred reset
   processing as soon as it reached the sender's last assigned TSN, but
   it didn't manage to do that in all cases.
 * It only defers DATA chunks for streams that are to be reset, not
   all DATA chunks with a TSN > sender's last assigned TSN. This was
   missed in the old implementation, but as it's now implemented
   strictly according to the RFC, this was now done.

[1] https://datatracker.ietf.org/doc/html/rfc6525#section-5.2.2
[2] RFC6525 cover stream resetting, and RFC3758 cover FORWARD-TSN, and
    the combination of these is not covered in the RFCs.

Bug: webrtc:14600
Change-Id: Ief878b755291b9c923aa6fb4317b0f5c00231df4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/322623
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40889}
2023-10-09 09:47:57 +00:00
Victor Boivie
ee0270b67c dcsctp: Rename message_id to mid
MID is a RFC8260 property on an I-DATA chunk, replacing the SSN property
on the DATA chunk in non-interleaved message. The MID stands for
"Message Identifier", and it was frequently named "message_id" in the
source code, but sometimes "mid". To be consistent and using the same
terminology as is most common in the RFC, use "mid" everywhere.

This was triggered by the need to introduce yet another "message
identifier" - but for now, this is just a refacotring CL.

Bug: None
Change-Id: I9cca898d9f3a2f162d6f2e4508ec1b4bc8d7308f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/322500
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40876}
2023-10-05 18:48:21 +00:00
Victor Boivie
a55746808e dcsctp: Only process meaningful FORWARD-TSN
Similar to change I602a8552a9a4c853684fcf105309ec3d8073f2c2, which
ensured that only new DATA chunks would be processed by the reassembly
queue by utilizing the data tracker, the same is done for FORWARD-TSN
chunks.

By having the data tracker gate keeping what is provided to the
reassembly queue, the reassembly queue can be simplified as well, which
is an added bonus, by removing last_assembled_tsn_watermark_ and
reassembled_messages_ as those were protecting the queue from
re-delivering messages it had already delivered, but as now the data
tracker would ensure that it wouldn't re-process DATA/FORWARD-TSNs, that
would have the same effect. In this CL, we will still update those
variables and save to the handover state, but not actually read from
them, and then when this change has been rolled out on the servers, I
can remove the variables as well.

The core change is to move validation from ReassemblyQueue::Handle
to DataTracker::HandleForwardTsn.

Some tests have been moved/replicated into data_tracker_test.cc to
ensure that it catches the issues that the reassembly queue did earlier.

Bug: webrtc:14600
Change-Id: I75c1d5911185d594f73c8b1e6bcf776e88f5b7c7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/321603
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40856}
2023-10-02 16:05:11 +00:00
Victor Boivie
a93f581705 dcsctp: Don't generate FORWARD-TSN across stream resets
This was a fun bug which proved to be challenging to find a good
solution for. The issue comes from the combination of partial
reliability and stream resetting, which are covered in different RFCs,
and where they don't refer to each other...

Stream resetting (RFC 6525) is used in WebRTC for closing a Data
Channel, and is done by signaling to the receiver that the stream
sequence number (SSN) should be set to zero (0) at some time. Partial
reliability (RFC 3758) - and expiring messages that will not be
retransmitted - is done by signaling that the SSN should be set to a
certain value at a certain TSN, as the messages up until the provided
SSN are not to be expected to be sent again.

As these two functionalities both work by signaling to the receiver
what the next expected SSN should be, they need to do it correctly not
to overwrite each others' intent. And here was the bug. An example
scenario where this caused issues, where we are Z (the receiver),
getting packets from the sender (A):

 5  A->Z          DATA (TSN=30, B, SID=2, SSN=0)
 6          Z->A  SACK (Ack=30)
 7  A->Z          DATA (TSN=31, E, SID=2, SSN=0)
 8  A->Z          RE_CONFIG (REQ=30, TSN=31, SID=2)
 9          Z->A  RE_CONFIG (RESP=30, Performed)
10          Z->A  SACK (Ack=31)
11  A->Z          DATA (TSN=32, SID=1)
12  A->Z          FORWARD_TSN (TSN=32, SID=2, SSN=0)

Let's assume that the path Z->A had packet loss and A never really
received our responses (#6, #9, #10) in time.

At #5, Z receives a DATA fragment, which it acks, and at #7 the end of
that message. The stream is then reset (#8) which it signals that it
was performed (#9) and acked (#10), and data on another stream (2) was
received (#11). Since A hasn't received any ACKS yet, and those chunks
on SID=2 all expired, A sends a FORWARD-TSN saying that "Skip to TSN=32,
and don't expect SID=2, SSN=0". That makes the receiver expect the SSN
on SID=2 to be SSN=1 next time at TSN=32.

But that's not good at all - A reset the stream at #8 and will want to
send the next message on SID=2 using SSN=0 - not 1. The FORWARD-TSN
clearly can't have a TSN that is beyond the stream reset TSN for that
stream.

This is just one example - combining stream resetting and partial
reliability, together with a lossy network, and different variants of
this can occur, which results in the receiver possibly not delivering
packets because it expects a different SSN than the one the sender is
later using.

So this CL adds "breakpoints" to how far a FORWARD-TSN can stretch. It
will simply not cross any Stream Reset last assigned TSNs, and only when
a receiver has acked that all TSNs up till the Stream Reset last
assigned TSN has been received, it will proceed expiring chunks after
that.

Bug: webrtc:14600
Change-Id: Ibae8c9308f5dfe8d734377d42cce653e69e95731
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/321600
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40829}
2023-09-28 11:31:02 +00:00
Victor Boivie
06fbe63cbf dcsctp: Exit deferred stream reset on FORWARD-TSN
https://datatracker.ietf.org/doc/html/rfc6525#section-5.2.2:

E2:  If the Sender's Last Assigned TSN is greater than the cumulative
        acknowledgment point, then the endpoint MUST enter "deferred
        reset processing". ...  until the cumulative
        acknowledgment point reaches the Sender's Last Assigned TSN.

The cumulative acknowledgement point can not only be reached by
receiving DATA chunks, but also by receiving a FORWARD-TSN that
instructs the receiver to skip them. This was only done for DATA and not
for FORWARD-TSN, which is now corrected.

Additionally, an unnecessary implicit sending of SACK after having
received FORWARD-TSN was removed as this is done anyway every time a
packet has been received. This unifies the processing of DATA and
FORWARD-TSN more.

Bug: webrtc:14600
Change-Id: If797d3c46e741074fe05e322d0aebec765a87968
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/321400
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40811}
2023-09-26 07:30:24 +00:00
Victor Boivie
77df7ffd0b dcsctp: Cleanup use of matchers
More general matches that can be reused, less specialized ones.

Bug: None
Change-Id: I12ea98caf4f566168566173a509c204bd25e5a13
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/321123
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40804}
2023-09-25 17:39:28 +00:00
Victor Boivie
850296b7a4 Reapply "dcsctp: Negotiate zero checksum"
The handover state has been added with
commit daaa6ab5a8.

This reverts commit 014cbed9d2.

Bug: webrtc:14997
Change-Id: Ie84f3184f3ea67aaa6438481634046ba18b497a6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/320941
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Reviewed-by: Jeremy Leconte <jleconte@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40794}
2023-09-23 21:33:52 +00:00
Victor Boivie
a7c6de9068 dcsctp: Add retransmission counters to metrics
Bug: webrtc:15458
Change-Id: Ib90cb0b9a94e1f358685ed319538654b0c8ed5c4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/318581
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40683}
2023-09-03 21:50:01 +00:00
Victor Boivie
014cbed9d2 Revert "dcsctp: Negotiate zero checksum"
This reverts commit a736f30a5f.

Due to a downstream project not supporting this
new handover state, it fails. Handover state needs
to be submitted first, then downstream project needs
to be updated, and finally the code changes can be
submitted.

Bug: webrtc:14997
Change-Id: I8551e349408d9bf4eb593cb948279d659467fe20
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/302821
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39923}
2023-04-23 22:25:44 +00:00
Victor Boivie
a736f30a5f dcsctp: Negotiate zero checksum
If configured, attempt to negotiate "zero checksum
acceptable" capability, which will make the outgoing
packets have a fixed checksum of zero. Received
packets will not be verified for a correct checksum
if it's zero.

Also includes some boilerplate:
 - Setting capability in state cookie
 - Adding capability to handover state
 - Adding metric to know if the feature is used

This feature is not enabled by default, as it will be
first evaluated with an A/B experiment before making
it the default.

When the feature is enabled, lower CPU consumption for
both receiving and sending packets is expected. How
much depends on the architecture, as some architectures
have better support for generating CRC32 in hardware
than others.

Bug: webrtc:14997
Change-Id: If23f73e87220c7d42bd4f9a92772cda16bc18fcb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/299076
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39920}
2023-04-21 15:31:35 +00:00
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
2a3942fec1 dcsctp: Add transmission_control_block_test
This component is mostly "glue" and is heavily tested in the
socket tests, but not the ToString method, which results in
getting "low test coverage" warnings.

So for the sake of it, add a test that verifies that it works.

Bug: None
Change-Id: Id2b75e2798f334452be50631ef1ff15f53fe4157
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/300441
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39826}
2023-04-12 13:31:24 +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
4fbf555989 dcsctp: Make use of log_prefix consistent
The log_prefix frequently used in dcSCTP is intended to be used
to separate logs from different sockets within the same log output,
typically in unit tests. Every log entry always has the file and
line, so it's not important to add more information to the log prefix
that indicates _where_ it's logged. So those have been removed.

Also, since log_prefix is a string (typically 32 bytes) and it's
never changing during the lifetime of the socket, pass and store it
as a absl::string_view to save memory.

Bug: None
Change-Id: I10466710ca6c2badfcd3adc5630426a90ca74204
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/274704
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39571}
2023-03-15 22:15:05 +00:00
Victor Boivie
871ad523fa dcsctp: Only send packets if there is a TCB
This was a mistake from change 273800 in that it could try to send
packets if there wasn't a connection established - when tcb_ was
nullptr.

Bug: chromium:1360268
Change-Id: Idd4406071dbd8ac89303aef61840895505417569
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/274405
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Auto-Submit: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38031}
2022-09-07 21:47:05 +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
dd1eb2e1ec dcsctp: Send buffered data directly on response
When a stream reset response has been received, this may result
in unpausing the streams (either because it was successful or
because it failed - but streams will be unpaused). Directly after
receiving the response, send out any pending chunks that are
ready to be sent.

Before this CL, they would eventually be sent out, but that is
unnecessary and undeterministic.

Bug: webrtc:14277
Change-Id: Ic1ab38bc3cea96cfec7419e25001f12807523a3a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/273800
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38009}
2022-09-05 10:52:00 +00:00
Victor Boivie
504198a50e dcsctp: Apply chunk before apply deferred reset
When a RECONFIG has been received with a last assigned TSN that is
not yet seen by the receiver, it will enter deferred reset mode
(https://www.rfc-editor.org/rfc/rfc6525#section-5.2.2, E2).

When more DATA is received, moving the cumulative acknowledgment point,
the request will finally be processed. But the last chunk that has the
same TSN as the last assigned TSN was before this CL not applied before
doing the reset - it was applied after.

This would result of a message getting lost or possibly getting
truncated or incorrectly merged with another.

Handling the message before resetting the stream is the simple
solution here.

Bug: webrtc:14277
Change-Id: Iea9fa227778077a9ff2f78bc77b5d93cc32b702b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/273323
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37993}
2022-09-02 11:25:48 +00:00
Victor Boivie
e0b45c268e dcsctp: Expose negotiated stream counts
To allow the transport to be able to know which ranges of
stream identifiers it can use, the negotiated incoming/inbound
and outgoing/outbound stream counts will be exposed. They are
added to Metrics, and guaranteed to be available from within
the OnConnected callback.

In this CL, dcSCTP will not validate that the client is sending
on a stream that is within the negotiated bounds. That will be
done as a follow-up CL.

Bug: webrtc:14277
Change-Id: Ic764e5f93f53d55633ee547df86246022f4097cf
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/272321
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37876}
2022-08-23 08:51:38 +00:00
Danil Chapovalov
6ba4b63f3a Remove usage of rtc::MessageHandler in net/dcsctp
Bug: webrtc:9702
Change-Id: I80f7fb7406f91a9bfc80e040a72d4af4950187fb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/272062
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Auto-Submit: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37818}
2022-08-18 09:18:40 +00:00
Mirko Bonadei
3b205da7e4 Increase precision of SimulatedTaskQueue (from ms to us).
Bug: b/239155933
Change-Id: I1b90a969b9f781fe2902aa822020590683a04b7d
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/270923
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37719}
2022-08-09 11:34:18 +00:00
Danil Chapovalov
c05a1be5b4 Migrate remaining webrtc usage of TaskQueueBase to absl::AnyInvocable
Bug: webrtc:14245
Change-Id: I8de2c23da5fbdfc0b1efbbe07fb6e8de744424a3
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/268191
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37565}
2022-07-20 08:15:08 +00:00
Danil Chapovalov
ecf88f4ade Migrate net/dcsctp/ to absl::AnyInvocable based TaskQueueBase interface
Bug: webrtc:14245
Change-Id: Ibf34bdfa1b623c712978728abc4dd821bf2cb089
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/267981
Auto-Submit: Danil Chapovalov <danilchap@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37458}
2022-07-06 09:37:53 +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
00c614272a dcsctp: Refactor send queue (2/2)
Let the send queue generate callbacks directly.

No functional change - pure refactoring.

Bug: webrtc:5696
Change-Id: Ic1e8ccba9612c5955e599c5d8257a5fa6980f666
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264143
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37401}
2022-07-01 15:51:44 +00:00
Victor Boivie
5e21262a44 dcsctp: Add API for lifecycle events
This CL adds the API to enable message lifecycle events to be generated.
Those can in turn be used to generate metrics, e.g. latency metrics
tracking the time to send a message, the time until it's acknowledged,
and metrics tracking how often messages are expired.

This will be used to validate that message interleaving really improves
latency for high priority data channels.

The actual implementation of the API will be provided in follow-up CLs.

Bug: webrtc:5696
Change-Id: Ic06f8244d1c79a336975e35479130521dff17519
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264141
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37396}
2022-07-01 10:59:25 +00:00
Victor Boivie
5b2556e9cd dcsctp: Add metric for using message interleaving
There was also some refactoring to create the TCB at the same time,
to ensure the metric is always set.

Bug: webrtc:13052, webrtc:5696
Change-Id: I5557ad5f0fc4a0520de1eaaafa15459b3200c4f5
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/262259
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37388}
2022-07-01 08:12:44 +00:00