The assignment is triggered by the MSC by sending an ASSIGNMENT REQUEST
with a group call reference. The reference is used to find the VGCS/VBS
channel that belogs to the referenced call.
The existing VGCS/VBS channel is reactivated. This will put the channel
into a state where the MS can establish the link on it, to complete the
assignment. The old connection is released by the MSC and assignment
completion is handled by the VGCS FSM.
Change-Id: Idaa864cd5ce4df6c3193494ce12d91523c104d89
Related: OS#4852
bssmap_handle_ass_req_ct_speech() calls select_codecs(), which requires
a bts pointer.
An extra bts pointer is added to both function and used instead of
deiving it from the conn->lchan pointer. This funcion can then be called
if no channel is assigned (yet). (conn->lchan is NULL)
This function will be used by the VGCS/VBS call control also.
(Chg-Id: Id9e94fb4f27bb438b7093c031344a3400bfa34f1)
Change-Id: Ifc1e315d5282f01f8d1bd600d62476c2ae74eca9
Related: OS#4852
It was found that on a busy osmo-bsc process (>1000 concurrent calls
spead over different BTSs), a good amount of time is spent iterating the
subscribers list trying to find a subscriber based on a TMSI (1.60% of
total CPU time used by osmo-bsc).
This patch introduces a new rbtree under struct bsc_subscr_store which
allows storing all the busbs ordered by TMSI.
This way, lookup time changes O(N) -> O(log(N)), at the expense of
increased insert/deletion time O(1) -> O(log(N)).
Related: SYS#6200
Change-Id: If27429e715ef4b327177e427249e68321a6e83cc
Use the full gsm0808_chan_indicator value throughout the lchan related
structs (assignment_fsm_data, gsm_lchan, lchan_activate_info,
lchan_modify_info) instead of reducing it to the boolean
requires_voice_stream.
This is needed so we don't lose the information whether an lchan was
requested for data or speech (both need an rtp stream).
Add a new bsc_chan_ind_requires_rtp_stream function and use it in
conditionals like the previous requires_voice_stream.
Related: OS#4393
Change-Id: I1538c1e6d5cd61559af7c1e2860afd0269dda367
Replace check_requires_voice_stream, which used to iterate over
ch_mode_rate_list and verify that all entries are either for speech or
signalling. Instead verify in check_chan_mode_rate_against_ch_indctr,
that all entries of ch_mode_rate_list have a chan_mode that matches the
ch_indctr (data, speech, signalling; called "speech / data indicator" in
3GPP TS 48.008 § 3.2.2.11).
This ensures that all of them are either data, speech or signalling and
not mixed.
Related: OS#4393
Change-Id: Iee5cbfee84d7f2ad59ee2d5a19891a2b59bbafff
Remove "speech mode" from the log message, as the log message is
relevant for CSD too. According to 3GPP TS 48.008 § 3.2.1.1 note 13 the
IE shall be included for AoIP unless channel type is signalling.
Related: OS#4393
Change-Id: Idfab0b7f6e97a6b67d140f967ddfe9b29818586e
Handle assignment requests for CSD. In this initial version, the code
for non-transparent data mode is a stub.
Related: OS#5763
Depends: libosmocore Ia965cdd9f53af756e5ffaff9b8f389b5ad629969
Change-Id: I350bea15fd2158eb6edc9bc92f2dca48930736e9
Move the translation from osmo_sockaddr_to_str_and_uint into
bssmap_handle_ass_req_tp_rtp_addr, which will be used by
bssmap_handle_ass_req_ct_data in a future patch too.
Pass pointers to variables in req, instead of duplicating variables and
filling it in later (like in bssmap_handle_ass_req_ct_sign).
Related: OS#4393
Change-Id: I6bb16b26d89056dffa50bd8296fefe9315c587ca
Allow reusing common code in an upcoming bssmap_handle_ass_req_ct_data.
It won't use _osmux for now (maybe in the future?), but splitting it
out as well makes it consistent.
Related: OS#4393
Change-Id: I4d9a4df314b1e56b9c1f90c9d7914332b70b56f8
I find it weird that we store the A5 algorithm ID in a format that
is used on the wire: N + 1 (valid for both A-bis and A interfaces).
What confused me even more is that in some functions we print it
as if it was in a normal, human-readable format. And this is
also why one can see weird constructions like:
if (lchan->encr.alg_id > ALG_A5_NR_TO_RSL(0)) { ... }
Let's ensure that our internal structures use the A5/N format:
alg_id=0: A5/0 (0x01 on the A-bis/A interface)
alg_id=1: A5/1 (0x02 on the A-bis/A interface)
alg_id=2: A5/2 (0x03 on the A-bis/A interface)
...
alg_id=7: A5/7 (0x08 on the A-bis/A interface)
so that we can print and compare the value of alg_id without using
additional arithmetics. Let's also rename 'alg_id' to 'alg_a5_n'
as it most clearly indicates which representation it is storing.
This is how the above code snippet would look like:
if (lchan->encr.alg_a5_n > 0) { ... }
Change-Id: Ieb50c9a352cfa5481aebac2379e0a461663543ec
Historically, we first only had
BSS_MAP_MSG_ASSIGMENT_RQST
^
with missing N. libosmocore has this renamed a long time ago and
provides a shim #define that makes the typo version still work.
Having the typo is bad for grepping, so rather use the non-typo name.
Also rename the constant for the ass req counter which so far has a
similar typo, and fix the same typo in the counter description.
The counter name exposed on CTRL luckily doesn't have this typo in it.
Change-Id: Ieaa4f4e6e6f7e1563b1bd15a83f0c1a9112d2312
Teach osmo-bsc to handle empty N-Connect. So far we were always
expecting user data in an SCCP N-Connect from an MSC. However, it is
perfectly valid for an initial BSSMAP request to follow later.
This is relevant for:
- Handover Request (incoming inter-BSC handover)
- Perform Location Request (query physical location of the MS)
Add state WAIT_INITIAL_USER_DATA with new timeout net X25. Always enter
this state so that we don't have two separate code paths for handling
initial user data.
Related: SYS#5864
Change-Id: I535c791fa01e99a2226392eb05f676ba6c3cc16e
Improve the function doc. Remove a comment at a caller, because that
information is what the function doc is for.
Rename the array to codec_by_strength, because it is not the codec
strength but the codec number listed in the array.
Related: SYS#5839
Change-Id: Iaed6b97c31e4ccb1f28ca7e64596d5e20563b392
In the field we saw Handover Requests without any Chosen Encryption
Algorithm IE, and osmo-bsc completely failed on those. This made me
understand my mistake from when I wrote this handover code.
So far, from a BSSMAP Handover Request, we (I) used only the Chosen
Encryption Algorithm IE to pick the encryption to use on the target
lchan. That is very wrong.
Instead, figure out the intersection of permitted algorithms MSC & BSC,
and pick the best of those. Which means, actually, completely ignore the
Chosen Encryption Algorithm IE.
In the message, the permitted algorithms are passed as a bitmask. The
current code using gsm0808_dec_encrypt_info() passes this on as an
array. In order to select_best_cipher(), I could convert that array back
to a bitmask. Instead pass the bitmask on from message decoding
alongside the struct gsm0808_encrypt_info in req->ei_as_bitmask.
In handover_end(), change the condition so that we can also pass
HO_RESULT_FAIL_RR_HO_FAIL to emit a Handover Failure.
Related: SYS#5839
Change-Id: Iffedc981b60d309ed2e5decd5efedee07a757b53
The naming confused me so that I wrote buggy code again. Hopefully this
clarifies which representations the code paths are using.
In the macro code, highlight the error case of n <= -1 explicitly.
Also add ALG_A5_NR_TO_PERM_ALG_BITS. I need the 1<<n case in an
upcoming patch.
Related: SYS#5839
Change-Id: I7557ae97764bba09c906748a18e9031dfb362611
The SAPI "n" REJECT messages were being sent with DLCI keeping the RSL
LINK ID format, which is not the same for CC bits.
With this patch, TTCN3 test BSC_Tests.TC_rll_sapi_n_reject_dlci_cc
passes again.
Related: OS#4728
Related: SYS#5047
Change-Id: Icc187f594743040a3d9b8beff7d9cfc21dd6eb08
From the nature of the lchan_activate_info.tsc_set and .tsc, it is easy
to forget to set tsc_set,tsc = -1 to use default TSC Set and TSC values.
Handover code is one such instance that forgets to set -1.
Change the semantics of tsc_set and tsc so that this kind of error can
not happen again as easily: use a separate bool to flag whether to use
the default config or explicit values.
Implicitly fix the lchan_activate_infos "launched" in handover_fsm.c as
well as abis_rsl_chan_rqd_queue_poll().
Related: OS#5244 SYS#4895
Related: I1ed6f068c85b01e5a2d7b5f2651498a1521f89af (osmo-ttcn3-hacks)
Change-Id: Iae20df4387c3d75752301bd5daeeea7508966393
Instead of having static const structs in header files (which end up
duplicated in each and every compile unit!), have one .c file with the
rate_ctr and stat_item descriptions.
Related: SYS#5542
Change-Id: I8fd6380b5ae8ed2d3347e7cfbf674c30b6841ed9
Receive and store the Kc128 key from MSC, and use as key sent to BTS if
A5/4 is the chosen encryption algorithm.
(A5/4 in handover will follow in a separate patch)
Related: SYS#5324
Change-Id: I7c458c8a7350f34ff79531b3c891e1b367614469
An upcoming patch for A5/4 would need to add a kc128 arg and reject
cause rc to gsm0808_cipher_mode(). Instead prepare for less cruft by
just having a single function.
Related: SYS#5324
Change-Id: I7f7c635943990a251ae28ae7a0d69cc3a239a154
An unintended change in default behavior was introduced in patch:
"allow explixit TSC Set and TSC on chan activ / modif / assignment"
Ic665125255d7354f5499d10dda1dd866ab243d24
c33eb8d569
Set tsc_set and tsc = -1 for all lchan_activate_info and
assignment_request requests to actually yield the default behavior of
selecting the TSC based on the timeslot cfg or the BSIC value.
By setting tsc = 0 implicitly, the patch caused all requests to ask for
tsc 0 instead of calling gsm_ts_tsc().
For a Channel Mode Modify in assignment_fsm, pass the lchan's current
TSC to keep it unchanged.
osmo-ttcn3-hacks Id67a949e0f61ec8123976eb8d336f04510c55c01 adds a test
to verify the expected TSC in all of the activation, assignment and
modify messages. Current osmo-bsc master fails, this patch fixes.
Related: SYS#5315 OS#4940 Ic665125255d7354f5499d10dda1dd866ab243d24
Change-Id: If12df11511fe22ea167782f776736a1a9c484b1f
I noticed during testing that an lchan used as TCH/F in fact still had
its channel mode set to Signalling -- because on Assignment, the Speech
mode used to be placed in the *previous* lchan and the new lchan was
never updated after the Activ ACK. This is unbearable confusion which I
complained about numerous times, so far mostly for cosmetic reasons. But
implementing re-assignment properly actually requires this to be cleaned
up.
Keep all volatile chan mode settings in lchan->activate.* or
lchan->modify.*, and only update lchan->* members when an ACK has been
received for those settings. So a failed request keeps a sane state.
Make sure that those settings are in fact updated in the proper lchan,
upon an ACK, so that subsequent re-assignment or mode-modify know the
accurate lchan state.
Related are upcoming patches that sort out the AMR multirate
configuration in a similar fashion, see
Iebac2dc26412d877e5364f90d6f2ed7a7952351e
Ia7519d2fa9e7f0b61b222d27d077bde4660c40b9
Ie57f9d0e3912632903d9740291225bfd1634ed47.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie0da36124d73efc28a8809b63d7c96e2167fc412
So far, only the MSC asked for Assignment via Assignment Request, which
we answer with a BSSMAP Assignment Complete or Assignment Failure when
done.
When Assignment is triggered for any other reason (congestion
resolution, VAMOS, VTY), we will not send any such messages to the MSC.
Additional enum values will be added in subsequent commits:
Id56a890106b93fcee67ac9401b890e7b63bba421 ASSIGN_FOR_CONGESTION_RESOLUTION
If006f5caaf83b07675f57e5665cfa79328da55e6 ASSIGN_FOR_VTY
Related: SYS#5315 OS#4940
Change-Id: Ie0cddbdb00abcec78e153f4ae6d04ce75080a111
In practice, '+ true' may result in '+ 1', but that is not type safe. We
rely on the number of items added by summing up booleans, rather make it
explicitly 1.
Change-Id: I17a82f4f208203b748ba2d6ace0ddc06f87c1cef
"""
The old BSS shall inform the new BSS of the MS's last used E-UTRAN PLMN
in the "Last used E-UTRAN PLMN ID" information element included in the
"Old BSS to New BSS information" Information Element if this information
is present.
"""
Depends: libosmocore.git Change-Id I6280ce1abc283f1491bc6f391b2dd952df33a16b
Related: SYS#5337
Change-Id: I6cf54f9a16d598f98dc56b25f0fef56225a25a28
From 3GPP TS 48.008 sec 3.1.30 "Common ID":
"""
If the SCCP connection is established due to CSFB from E-UTRAN and the MSC supports
return to the last used PLMN after CS fallback, then it should send the COMMON ID message
to the BSS including the Last used E-UTRAN PLMN ID information element if available at
the MSC immediately following the successful SCCP connection setup.
"""
Furthermore, 3GPP TS 48.008 version 16.0.0 Release 16 "3.2.1.21 CLEAR COMMAND",
for field CSFB Indication, states:
"""
NOTE: This information element doesn't serve any useful purpose. MSCs should not send the
information element unless it is required by the recipients (due to the need to interwork
with older versions of the protocol). It is expected that in future versions of the present
document, this information element will be deleted from this message.
"""
Hence, build up the EUTRAN neighbor list based on whether we received
the Last E-UTRAN PLMN ID IE during Common Id. In the future, we should
probably filter the list while populating it based on the received IE.
This change will also allow reusing same mechanism for SRVCC
EUTRAN->GERAN support, where te Last E-UTRAN PLMN ID IE can be found
inside "Old BSS to New BSS information" IE in msg HANDOVER REQUEST.
Related: SYS#5337
Change-Id: I5d290ac55eca5adde1c33396422f4c10b83c03d5
This change will allow handling more IEs in the future, like
"Last used E-UTRAN PLMN ID" one.
Related: SYS#5337
Change-Id: I96a0e1a7491fabf7aaad62207886821ad6194927
We cannot simply use the highest 'x' in A5/x codecs.
For A5/7 through A5/3, larger 'x' means better.
But: A5/1 is better than A5/2, so we need to prefer the former
over the latter.
Change-Id: I399fff8d07d1bfcbc6b385e90914ff6d9e00eb73
Closes: OS#4975
The function bssmap_handle_cipher_mode() suggests to check if an lchan
is actually present when it gets called, but it only checks for conn.
This might lead to a segfault later in the execution path.
Change-Id: I3103ec89cd6dce1a11ea8e9f8187373e4114e852
So far we would cancel ongoing Paging for a given MSC only after receiving a
RESET message from that BSC. However, the typical operation would be that
OsmoBSC *sends* a RESET and receives a RESET-ACK.
Instead, move the call to within osmo_bsc_sigtran_reset(). This is also called
when OsmoBSC considers the A-interface link to be lost, from the a_reset.c
code, after multiple SCCP connection failures.
Change-Id: Ia14b916be56563d18632c69a833084e71799a468
Data Link Connection Identifier (DLCI) is defined in 3GPP TS 48.006,
section 9.3.2, and coded as follows:
.... .SSS - SAPI value used on the radio link;
CC.. .... - control channel identification:
00.. .... - indicates that the control channel is not further specified,
10.. .... - represents the FACCH or the SDCCH,
11.. .... - represents the SACCH,
other values are reserved.
RSL Link Identifier is defined in 3GPP TS 3GPP TS 48.058,
section 9.3.2, and coded as follows:
.... .SSS - SAPI value used on the radio link;
...P P... - priority for SAPI0 messages;
CC.. .... - control channel identification:
00.. .... - main signalling channel (FACCH or SDCCH),
01.. .... - SACCH,
other values are reserved.
As can be seen, CC bits in both DLCI and RSL Link Identifier
are coded differently. Therefore, we cannot just assign
one identifier to another, we need to do conversion.
I noticed that osmo-bsc indicates DLCI '01000011'B for SMS
messages sent over SACCH/F (SAPI3), and this is wrong because
'01'B is reserved. Let's fix this.
P.S. Interesting coincidence: section 9.3.2 in both documents.
Change-Id: If4d479a54cad467f53b49065c1c435a4471ac7d2
Related: Ica69ae95b47a67ba99ba9cc36629b6bd210d11e4
Related: OS#3716
During LCS development, I'm getting use count bugs and would like to see use
token strings to figure it out.
Change-Id: I29bf60059d4cf7bb99a00753e6cdc149baf95f94
To distinguish between the CN requiring a Complete Layer 3 response, or just
the BSC requiring a TA, allow recording a separate for-LCS paging reason.
Change-Id: Ib28d1599ae4e483727398859d07de4490fbc31f0
Andreas Eversberg
Pau Espin
Oliver Smith
Neels Hofmeyr
Vadim Yanitskiy
Harald Welte
Philipp Maier