Changes

msc: CC SETUP MT speech: verify bearer capabilities

Verify that the MSC sends the bearer capability IE from 3GPP TS 24.008 §
D.1.2 for speech in the network to MS direction, instead of allowing
e.g. what osmo-msc master and latest release currently do:

 - Filling out radio channel requirement the same way as the MS to
   Network direction, which is wrong for the Network to MS direction:
   "Bits 6 and 7 are spare bits. The sending side (i.e. the network)
   shall set bit 7 to value 0 and bit 6 to value 1." (3GPP TS 24.008
   Table 10.5.102)

 - Sending a speech list in the Network to MS direction, which seems to
   be allowed in theory and MS are supposed to ignore it (end of Table
   10.5.103) but causes bugs in some MS in practice. Therefore it is
   better to ensure that osmo-msc does not send it (OS#6656).

Implement this in f_mt_call_complete(), which gets used e.g. by
TC_lu_and_mt_call.

Depends: osmo-msc I7046e9244fd9d4301ee2c4df1147a619f753739c
Related: OS#6657, OS#6655, OS#6656
Change-Id: I8fd33cf2f7fb8a1c34851ecf54fccddd2efd0536

Add optonal e-RAB lists to HANDOVER messages

These lists are required to test release of e-RABs during handover
prparation and indication of failed e-RABS during handover resource
allocation.

New templates for the new lists and list items are added.

Related: SYS#7309
Change-Id: I78d2fa8e72bb672674727a01d5c5a9aaf31cab7b

S1GW: Add test case to test release of e-RABs during handover preperation

HANDOVER COMMAND allows e-EABs to be forwarded or to be released. The
test provides two lists and expects osmo-s1gw to release only those
e-RABs that are included int the "E-RABs to Release List" IE.

Related: SYS#7309
Change-Id: Ic70ba19c0a6e349f63aae124607d075b6d19e779

S1GW: Add test case to test release of failed e-RABs during handover resource allocation

HANDOVER REQUEST ACKNOWLEDGE indicates admitted and failed eRABs. The
test provides two lists and expects osmo-s1gw to release only those
e-RABs that are included int the "E-RABs Failed to Setup List" IE.

Related: SYS#7309
Change-Id: Ic14f560ae16b8386e58ac85f8af53b19d7c7a5c9

SGsAP_Emulation: Introduce proper support for server-mode

Prior to this commit, only initial (not really useful) SCTP server-mode
support existed in SGsAP_Emulation.
This is basically because MSC_Tests uses the SCTP client-mode, and
MME_Tests_SGsAP were not yet in a fully working state.

In server-mode, we have a conn_id for the listening socket and a conn_id
for the accepted socket; track them properly.
Moreover, in server node we definetly need some sort of event to wait
for the client to connect; introduce it.
Based on existing work in Iuh_Emulation.

Change-Id: Iccf4ac96c56e947529f0ffc06428e2325a115d50

mme: Initial working state for MME_Tests_SGsAP.ttcn tests

MME_Tests_SGsAP.ttcn tests were introduced to the repository many years
ago (~2019), but they were mostly WIP and were never run as part of the
regular testsuite.

This commit reworks and extends previous work to get them up to date
with current MME_Tests and makes most of them passing.

TC_sgsap_alert_* tests are still in WIP and will be fixed in follow-up
work.

Related: OS#6850
Change-Id: If07f1a67eb4213985da82afec94adb08786a0980

mme: Store and check {mme,enb}_ue_id over S1AP

* Generate a different enb_ue_id based on imsi_suffix, and store it
  during startup of ConnHdlr.
* Validate the MME sends the expected message to the expected enb_ue_id.
* Store the mme_ue_id and validate also that MME keeps using it.

A new procedure is added to S1AP_Emulation, similar to what already
exists in NGAP_Emulation, to obtain the mme_ue_id allocated by the peer.
This is needed because upon rx of DL NAS Transport messages we only
receive the upper layer NAS decoded in the Connhdlr, so we can't store
and track the MME ID early enough.

Change-Id: I62902db3851f48ce9f80cb1cc84797735c0091de

mme: Introduce test TC_s1ap_tau_periodic

Change-Id: I261c3421f6a082e0d610ece4cc96d3e031022891

mme: Fix implementation of TC_sgsap_alert*

Change-Id: I717c6f153ae77874170bf03e7a6c7bb628d12dba