Hello Jenkins Builder,

I'd like you to reexamine a change. Please visit

https://gerrit.osmocom.org/c/osmo-msc/+/31698

to look at the new patch set (#2).

Change subject: [codecs filter] send + receive SDP via MNCC ......................................................................

[codecs filter] send + receive SDP via MNCC

Transmit and receive full SDP information via MNCC, to accurately pass codecs choices between the call legs.

In msc_vlr_test_call.c test_call_mt(), show that when receiving MNCC, the codec information in SDP overrules the Bearer Cap codec information -- we expect to still receive inaccurate Bearer Cap from e.g. osmo-sip-connector, because we have chosen to add SDP to MNCC instead of trying to fix the codecs represented in Bearer Cap.

For internal MNCC, the MT call leg now knows which codec the MO has chosen and assigned.

For external MNCC, osmo-sip-connector receives SDP about our codecs choices and sends it in SIP messages, and we also receive the full SDP information from the remote SIP leg.

Update the SDP in codec_filter every time it is received, to always have the latest SDP information from the remote leg.

CC MNCC | ---ALERTING--> | add local side SDP to MNCC msg | <--ALERTING--- | store remote side SDP | <--SETUP-RESP- | store remote side SDP | --SETUP-CNF--> | add local side SDP to MNCC msg | -RTP-CREATE--> | use codec_filter, add local side SDP to MNCC msg | <-RTP-CONNECT- | store remote side SDP

There still is one problem: when initiating MNCC, we do not yet know the RTP address and port to be used for the CN side, because the CN CRCX happens later. So far we send 0.0.0.0:0 as RTP endpoint in the SDP, until the CN CRCX is done. A subsequent patch moves CN CRCX to an earlier time, adding proper RTP information right from the start.

Related: SYS#5066 Change-Id: Ie0668c0e079ec69da1532b52d00621efe114fc2c --- M include/osmocom/msc/rtp_stream.h M src/libmsc/gsm_04_08_cc.c M src/libmsc/rtp_stream.c M tests/msc_vlr/msc_vlr_test_call.c M tests/msc_vlr/msc_vlr_test_call.err 5 files changed, 235 insertions(+), 24 deletions(-)

git pull ssh://gerrit.osmocom.org:29418/osmo-msc refs/changes/98/31698/2