Nils Ohlmeier [:drno] Assignee
	Description • 8 years ago

Bug 1160558 added support for sctp-sdp-21 and adds support for parsing the new SDP attribute 'a=max-message-size'.
But the value is not taken from the SDP and handed to the SCTP stack. And we are also not emitting max-message-size (since it's optional).

	Nils Ohlmeier [:drno] Assignee
	Comment 2 • 7 years ago

For the record the plan here is to start emitting a=max-message-size even though we are still offering the old style data channel format.
And then we use absence of the max-message-size and if streams is 256 (assuming Chrome always used 1024 like Chrome 58 does today) that we are connected to an old Firefox version which does not support EOR (see bug 979417). Note: this logic is not part of this patch here (so far).

I checked that with the presence of a=max-message-size we can still establish data channels with Chrome.

	Randell Jesup [:jesup] (needinfo me)
	Comment 3 • 7 years ago
mozreview-review

Comment on attachment 8873313 [details]
Bug 1335262: read and emit datachannel max-message-size.

https://reviewboard.mozilla.org/r/144770/#review148908

::: netwerk/sctp/datachannel/DataChannelProtocol.h:21
(Diff revision 1)
>  #error "Unsupported compiler"
>  #endif
>  
> -// Duplicated in fsm.def
> -#define WEBRTC_DATACHANNEL_STREAMS_DEFAULT 256
> +#define WEBRTC_DATACHANNEL_STREAMS_DEFAULT          256
> +#define WEBRTC_DATACHANNEL_PORT_DEFAULT             5000
> +#define WEBRTC_DATACHANELL_MAX_MESSAGE_SIZE_DEFAULT 64000

draft-ietf-mmusic-sctp-sdp-26 says the default is 64K.  While "K" is indeterminate in definition here, I had assumed it was 65536, not 64000.

Suggest checking with Crister/etc about clarifying that.

	Nils Ohlmeier [:drno] Assignee
	Comment 5 • 7 years ago
mozreview-review-reply

Comment on attachment 8873313 [details]
Bug 1335262: read and emit datachannel max-message-size.

https://reviewboard.mozilla.org/r/144770/#review148908

> draft-ietf-mmusic-sctp-sdp-26 says the default is 64K.  While "K" is indeterminate in definition here, I had assumed it was 65536, not 64000.
> 
> Suggest checking with Crister/etc about clarifying that.

Pinged Christer.
And changed the code to 65536 as I personally don't care.

	Nils Ohlmeier [:drno] Assignee
	Comment 6 • 7 years ago

Christer confirmed that 65535 is/was the intended value (and forwarded the request to update the draft to WG and AD - because it pretty late in draft process).

	Pulsebot
	Comment 8 • 7 years ago

Pushed by drno@ohlmeier.org:
https://hg.mozilla.org/integration/autoland/rev/9fa721e390ad
read and emit datachannel max-message-size. r=jesup

	Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)
	Comment 9 • 7 years ago
bugherder

https://hg.mozilla.org/mozilla-central/rev/9fa721e390ad

	Gerry Chang [:gchang]
	Comment 10 • 7 years ago

54 RC build is released. Mark 54 won't fix.