Per-track fingerprint?

[wusspuss]

the sdp string libdatachannel generates goes as follows:

v=0
o=rtc 742103403 0 IN IP4 127.0.0.1
...
a=fingerprint:sha-256 ...
m=video 35837 UDP/TLS/RTP/SAVPF
c=IN IP4 192.168.100.3
...
m=audio 35837 UDP/TLS/RTP/SAVPF
c=IN IP4 192.168.100.3
...

other software I'm trying to get it to interact with produces things like

v=0
o=- 3719505103060116772 2 IN IP4 127.0.0.1
...
m=video 9 UDP/TLS/RTP/SAVPF 
c=IN IP4 0.0.0.0
a=fingerprint:sha-256 ...
...
m=audio 9 UDP/TLS/RTP/SAVPF
c=IN IP4 0.0.0.0
a=fingerprint:sha-256 ...

apparently libdatachannel specifies a fingerprint session-wide, while it can also be specified per media as in the latter example. Is the latter behavior something libdatachannel is compatible with, and how can I get it to do that, particularly with C api?

[paullouisageneau]

Fingerprints at media-level should not be an issue. However, if the fingerprints are different, which is weird but technically correct according to RFC 8122, it appears libdatachannel has the same bug as #982 for fingerprints, it will incorrectly pick the last one.

[wusspuss]

How can I get libdatachannel to produce sdp with fingerprints at media-level?

[paullouisageneau]

There is no way to make libdatachannel create SDP with fingerprints at media-level. You can still edit the SDP, but in practice you shouldn't need to do so. What is the other software? Does it support BUNDLE?

[paullouisageneau]

Parsing SDP with different fingerprints is fixed by #988.