Commit Graph

54 Commits

Author SHA1 Message Date
Vadim Yanitskiy ad51437eef gsm48_make_ho_cmd(): optionally add Synchronization Indication IE
Related: SYS#5838
Change-Id: I4e5b1163a71443d706f14ce4bfd5c2294c320432
(cherry picked from commit 53d05951a5)
2022-03-14 19:07:24 +03:00
Vadim Yanitskiy 0db447b49e gsm48_make_ho_cmd(): optionally add Cipher Mode Setting IE
According to 3GPP TS 44.018, section 9.1.15, the RR Handover Command
message may optionally contain the Cipher Mode Setting IE (10.5.2.9).
Section 9.1.15.10 states that this IE may be omitted in case of the
intra-RAT GERAN-to-GERAN handover, however in case of the inter-RAT
handover (e.g. EUTRAN-to-GERAN), this IE *shall* always be included.

Related: SYS#5838
Change-Id: I1d270e82d0a9b12897fc94dae4e8999aa132a22f
(cherry picked from commit 2902d91d69)
2022-03-14 19:07:10 +03:00
Vadim Yanitskiy 36aaf3574a gsm48_make_ho_cmd(): make 'struct gsm_lchan' pointer const
Related: SYS#5838
Change-Id: I731179bf7f5d711ca114e36af661faccf0caa19f
(cherry picked from commit 798a71eb30)
2022-03-14 19:06:21 +03:00
Vadim Yanitskiy fd60c40d60 gsm48_send_ho_cmd(): this function is not used, remove it
Related: SYS#5838
Change-Id: I9771d7e1f2073ebf6d900c067885485e54790bca
(cherry picked from commit 0a01573bc1)
2022-03-14 19:05:43 +03:00
Neels Hofmeyr e561e74bfe rename RSL_ENC_ALG_A5 to ALG_A5_NR_TO_RSL, clarify
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
2022-02-22 16:32:17 +01:00
Vadim Yanitskiy d4e2a2d5e1 gsm_04_08_rr: silently ignore RR UTRAN Classmark Change
Some UMTS capable phones (such as SE K800i) send this message
together with the 'normal' RR Classmark Change, what makes
osmo-bsc log the following warning:

  DCHAN NOTICE gsm_04_08_rr.c:1037
    lchan(0-0-1-SDCCH8-0)[0x562ea76d3ab0]{ESTABLISHED}:
      (type=SDCCH) Unknown RR message: UTRAN Classmark Change

We don't handle it, so just ignore without logging anything.

Change-Id: Icb8e44c9a06519ead9c3dc9308788c23505d4bb1
2021-08-29 17:50:05 +06:00
Neels Hofmeyr dc2bcdacdd cosmetic loop simplification in gsm48_multirate_config()
Change-Id: I52424ad6a0bf499fe040cf0a1de00e636a0a40fe
2021-06-10 16:15:35 +02:00
Neels Hofmeyr d37dcb9f68 RSL: rx and tx VAMOS Channel Number cbits for VAMOS lchans
Add the Osmocom-specific extension to indicate VAMOS shadow lchans in
RSL, in lchan lookup and RSL message transmission.

Note that RR messages containing cbits (Assignment Command, Handover
Command, ...) must *not* send Osmocom specific cbits to the MS. Only the
RSL messages directed to the BTS send Osmocom specific bits.

Related: SYS#5315 OS#4940
Depends: If33c1695922d110c0d2c60d5c0136caf2587194e (libosmocore)
Change-Id: I957eff0d2c33ec795eda75a4bff21965b0179f73
2021-06-10 16:15:35 +02:00
Neels Hofmeyr 43aeeaf05a RSL chan_nr: replace OSMO_ASSERT with error handling
It's bad to abort the program for an incompatible chan_nr.  Instead of
OSMO_ASSERT(), make sure that error handling happens all they way to the
original callers of gsm_lchan2chan_nr etc.

This is also preparation to add further error causes: Osmocom specific
cbits needed for a non-Osmo BTS.

Related: SYS#5315 OS#4940
Change-Id: I71ed6437c403a3f9336e17a94b4948fca295d853
2021-06-10 16:15:35 +02:00
Neels Hofmeyr 52a6b2cebf RR Assignment for VAMOS: send TSC Set
We already send the TSC Set in the RSL Channel Activation, telling the
BTS about the TSC Set. The MS needs to be instructed of the TSC Set in
the RR Assignment Command.

The first code to actually do an Assignment to a VAMOS activated lchan
will follow in If006f5caaf83b07675f57e5665cfa79328da55e6.

Change-Id: Ibf3b6d276fadf724c16a5225c03e96a27a056153
2021-06-10 16:15:35 +02:00
Neels Hofmeyr e3e317242c implement Channel Mode Modify to VAMOS mode
Put a (primary) lchan in VAMOS speech mode.
This is not yet about activating shadow lchans, this merely puts any
lchan in a VAMOS capable channel- and speech mode.

Protocol:

In RR Channel Mode Modify, send a spec conforming VAMOS channel mode as
well as an Extended TSC Set, wich adds the TSC Set to the training
sequence code value.

In RSL MODE MODIFY, send Osmocom specific extensions to indicate the TSC
Set and TSC, as well as the VAMOS channel mode; only to OsmoBTS type
cells.
- Set the Channel Mode's Channel Rate to Osmocom specific
  RSL_CMOD_CRT_OSMO_TCH_VAMOS_Bm / RSL_CMOD_CRT_OSMO_TCH_VAMOS_Lm
- Add the Osmocom specific Training Sequence IE containing both TSC Set
  and TSC.
(These are documented in the Abis manual.)

Implementation:

The internal API to request a Mode Modify is lchan_modify(info). Add to
this info the 'vamos' bool, set to true when the modification should put
the lchan in VAMOS channel mode or not.

When info.vamos == true, make sure the channel mode value is a VAMOS
one: in the copy of info->ch_mode_rate at lchan->modify.ch_mode_rate,
convert to the right VAMOS/non-VAMOS equivalent channel mode.

When the modification is through, set lchan->vamos.enabled
appropriately.

This patch also builds on Ic665125255d7354f5499d10dda1dd866ab243d24
'allow explixit TSC Set and TSC on chan activ / modif / assignment'
placing tsc_set and tsc values in the TSC related IEs.

Related: SYS#5315 OS#4940
Change-Id: Ibf53f4797d7491b17a33946fd7d920f038362b4c
2021-06-10 16:14:57 +02:00
Neels Hofmeyr 2f88133083 fixup for Mode Modify TSC
Use lchan->modify.tsc in gsm48_lchan_modify().

The TSC is chosen exactly once upon LCHAN_EV_REQUEST_MODE_MODIFY
(lchan_fsm.c), and that should be the only place calling gsm_ts_tsc().
All other mode modify code should just use the final lchan->modify.tsc.

This fixes an error in patch:
Ic665125255d7354f5499d10dda1dd866ab243d24
"allow explixit TSC Set and TSC on chan activ / modif / assignment"

Thanks to coverity for actually detecting this mistake.

Related: SYS#5315 OS#4940 CID#236233
Change-Id: I87ecf7d9266f37f4c775d029e277b614671a9401
2021-06-02 20:30:35 +02:00
Neels Hofmeyr 858a0211a0 lchan_fsm: introduce lchan.modify.ch_mode_rate to allow tweaking
lchan->modify.info.ch_mode_rate should remain unchanged, it is the
immutable request data. However, for VAMOS, we will want to
automatically see that the chan_mode is chosen correctly.

As a first step, place a mutable ch_mode_rate copy at
lchan->modify.ch_mode_rate, i.e. not in .modify.info, but in
.modify. Use that everywhere.

This is a non-functional change, preparing for a subsequent patch that
adds handling of VAMOS shadow lchans.

Change-Id: I8a3daac0287f15a59d3688388bb13e55facb2cea
2021-05-31 05:20:03 +00:00
Neels Hofmeyr e24da2ef95 ensure chan_mode comparisons in non-VAMOS mode
Both VAMOS- and non-VAMOS speech modes should result in indentical voice
handling. So make sure that all chan_modes are converted to non-vamos
before comparing / evaluating in switch statements.

Change-Id: I791e7966b1f8eaa3299a8a46abeb313cf5136e0b
2021-05-31 05:20:03 +00:00
Neels Hofmeyr c33eb8d569 allow explixit TSC Set and TSC on chan activ / modif / assignment
Activating / modifying to a VAMOS mode will require picking specific TSC
Set / TSC. It is a bad idea to pick the TSC in each message encoding
function, rather make this choice centrally.

So far we pick the training sequence code to use based on the timeslot
configuration, and this TSC is determined only upon encoding the RSL
messages.

Instead, pick the TSC to use upon the initial lchan activation /
modification request; store this in the request structs and pass through
the activation / modification code paths.

For VAMOS modes, we also need to pick a TSC Set. Do so also upon activ /
modif request. Note that the TSC Set is not yet applied in this patch,
it will be applied in upcoming VAMOS patches.

The activ / modif request may pass -1 for tsc_set and/or tsc to indicate
no specific choice of TSC Set and TSC, resulting in the same behavior as
before this patch.

For example, lchan->activate.info.tsc* may be passed as -1. The exact
choice for tsc_set and tsc is then stored in lchan->activate.tsc*, i.e.
one level up (the .info sub-struct is considered as immutable input
args). The lchan->activate.tsc* are the values actually encoded in RSL
messages. After the ACK, the lchan->activate.tsc* is stored in
lchan->tsc* to indicate the TSC actually in use. Same for modif.

Note that in 3GPP TS 45.002, the TSC Set are numbered 1 to 4, while the
TSC are numbered 0 to 7. On the wire, though, TSC Set is sent as 0 to 3
value. This is a weird discrepancy, odd choice made by the spec authors.
For conformance with the spec wording, I decided to pass the TSC Set
number as a 1-4 ranged value, and only convert it to the 0-3 on-the-wire
format upon message encoding. So log messages and VTY output will
indicate the first TSC Set as "1", but the first TSC as "0", as defined
in 3GPP TS 45.002, even if that is somewhat weird.

Related: SYS#5315 OS#4940
Change-Id: Ic665125255d7354f5499d10dda1dd866ab243d24
2021-05-31 05:20:02 +00:00
Neels Hofmeyr 5df7e771a8 gsm48_lchan2chan_desc(): expose TSC as param
Expose the training sequence code used in the RSL Channel Description IE
as an input parameter.

So far the Channel Description IE is always composed with a training
sequence code from gsm_ts_tsc(). For RSL commands enabling VAMOS mode,
specific training sequence codes are required.

So far, all callers still use gsm_ts_tsc(), making this a patch without
any functional change. Upcoming patches will pass specific TSC as
configured for VAMOS instead, in specific places.

Related: SYS#5315 OS#4940
Change-Id: I49503a6f5d25bb3bc9a0505bd79ed1d5c4f50577
2021-05-28 17:22:59 +00:00
Neels Hofmeyr 1b277ec2a2 RSL link: explicitly select rsl_link based on lchan
Prepare for VAMOS, where there will be secondary "shadow" lchans serving
secondary MS on the same timeslots. For those, RSL messages will need to
reflect a different stream ID aka TEI, via an rsl_link_vamos.

Make sure that every code path that sends an RSL message for a specific
lchan selects the RSL link via the new function rsl_chan_link(). When
VAMOS is implemented, this function can select the proper RSL stream.

Rename gsm_bts_trx.rsl_link to rsl_link_primary. This makes sure I'm not
missing any uses of the RSL link, and clarifies the code.

Related: SYS#5315 OS#4940
Change-Id: Ifbf16bb296e91f151d19e15e39f5c953ad77ff17
2021-05-28 17:22:59 +00:00
Neels Hofmeyr d508143dd3 AMR config cleanup step 3: generate AMR LV on msg composition
Firstly, do not store the encoded AMR length-value bits in gsm_lchan->*
before an activation/modify has actually succeeded.

And secondly, do not store the AMR LV structure in struct gsm_lchan at
all, but only generate the TLV exactly when a message is being composed.

In gsm48_multirate_config(), generate the LV directly to a msgb instead
of a static buffer first. gsm0408_test.c expected output verifies that
the generated LV bytes remain unchanged.

In lchan_mr_config(), introduce a target mr_conf argument, so that Chan
Act and Mode Modify may generate the filtered AMR config to different
locations (lchan->{activate,modify}.mr_conf_filtered).

Only after receiving an ACK for Activate/Modify, set
lchan->current_mr_conf from lchan->{activate,modify}.mr_conf_filtered.

Use the properly scoped lchan->activate.mr_conf_filtered for Chan Act,
lchan->modify.mr_conf_filtered for Mode Modify and
new_lchan->current_mr_conf for Handover Command as appropriate.

Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie57f9d0e3912632903d9740291225bfd1634ed47
2021-05-27 17:06:21 +02:00
Neels Hofmeyr 3625c90c22 eliminate lchan->rsl_cmode
Related: SYS#5315 OS#4940
Change-Id: I1c167b22bb6638a929488d093bde0f1a5fb227ad
2021-05-27 17:06:21 +02:00
Neels Hofmeyr 0951d75665 make sure channel mode and s15_s0 are updated only after an ACK
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
2021-05-27 17:06:21 +02:00
Neels Hofmeyr f3cce79f14 gsm48_send_rr_ass_cmd(): rename lchan to new_lchan
Clarify that this is the lchan that is being assigned to the MS, in
contrast to the current lchan.

Change-Id: I0de017f7c43ec495c2cd0f05f313740f42ab0bb1
2021-05-21 13:13:15 +00:00
Neels Hofmeyr b6d064c94f gsm48_send_rr_ass_cmd(): rename dest_lchan to current_lchan
This variable is the lchan that the Assignment Command should be sent
to, i.e. the MS's current lchan. The "dest" could be interpreted as the
destination of the assignment, the lchan that the MS should move to.

Change-Id: If2c102a8f1d45f84b6a765555abf7cd7a4749b0f
2021-05-21 13:13:15 +00:00
Pau Espin 5bc54d6ce8 Send EUTRAN neighs based on whether Common Id msg contained Last used E-UTRAN PLMN ID
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
2021-04-19 12:12:31 +02:00
Pau Espin 00ae402627 cosmetic: Fix typo in func description
Change-Id: I26cd31bc3e127cba17be508d10a5fd3cf6498901
2021-04-15 16:36:23 +02:00
Vadim Yanitskiy d63690e473 [hopping] gsm48_send_rr_ass_cmd(): use Cell Channel Description from SI1
Calling generate_cell_chan_list() on each Assignment Command is
quite expensive, because this function basically re-constructs
the Cell Allocation (using bitvec API) and the Frequency List
from scratch.  This IE can be borrowed from pre-calculated
SI1 message, so let's do this.

Change-Id: I9c8c5ae9059ff096765412b3f3c7181a94163afc
2021-04-06 04:38:28 +02:00
Neels Hofmeyr 4ae338d5b6 LCS: implement the bulk of Location Services
Depends: I4d7302a4853518916b6b425e710c10568eb2ffe5 (libosmocore)
Change-Id: I28314ba97df86a118497e9b2770e2e6e2484e872
2020-10-09 00:26:02 +02:00
Neels Hofmeyr 2001dd6cb5 compl l3: allocate conn in gsm_08_08.c, not gsm_04_08_rr.c
Move conn allocation to bsc_compl_l3(), from gsm0408_rcvmsg().

Drop dispatch of GSCON_EV_A_DISC_IND, because a) we did not receive such
DISC.IND, and b) the lchan release will discard the conn in the regular
fashion.

In upcoming LCS patch, bsc_compl_l3() will decide whether to allocate a new
conn or whether a conn from a Perform Location Request already exists for the
subscriber.

In this patch, it becomes clear that the conn->bsub is always NULL in
bsc_compl_l3(), and that the 'log_set_context(LOG_CTX_BSC_SUBSCR, conn->bsub);'
never has the intended effect. An upcoming patch will change that.

Change-Id: I92af0f0d54c4282d782f2b29d524a64006c3b674
2020-10-07 10:19:58 +00:00
Alexander Couzens 380831e678 gsm 04.08: correct calculate the Cell Selection Indicator after release of all TCH and SDCCH
When the measurement bandwidth was added the calculation of the maximum
length wasn't increased.

Fixes: 27a887f666 ("gsm 04.08: encode the LTE neighbors measurement bandwindth in Channel Release")
Change-Id: Ic8132fd988140c34b8e0fd8349f4518fcbaecc31
2020-09-15 11:47:11 +02:00
Alexander Couzens 27a887f666 gsm 04.08: encode the LTE neighbors measurement bandwindth in Channel Release
Encoding missing measurement bandwidth of LTE neighbors in Channel Release
(Cell selection indicator after release of all TCH and SDCCH value part).
The measurement bandwidth was encoded in the neighbors description transmitted in
SI2quater while missing in the Channel Release which would overwrite the
SI2quater measurement bandwidth.

Change-Id: I4847d840ba9d5ac56bd00e4f405dc47792008c0d
2020-09-10 20:23:11 +02:00
Philipp Maier 92eed41a99 lchan_fsm: make rsl mode-modify working again
osmo-nitb supports the modification of an lchan if the lchan is
compatible but in the wrong mode. This feature was dropped in the
transition to AoIP/bsc-split. However, osmo-bsc still has code to
generate and parse the messeages, but the FSMs do not support a mode
modify yetm

Lets add handling for mode-modify to the lchan_fsm and assignment_fsm in
order to support mode modify again

Change-Id: I2c5a283b1ee33745cc1fcfcc09a0f9382224e2eb
Related: OS#4549
2020-09-03 21:35:25 +02:00
Vadim Yanitskiy 9ff1c3d650 gsm_04_08_rr: fix hopping parameters in RR Handover Command
A similar problem has already been fixed in [1]:

  - include GSM48_IE_MA_AFTER instead of GSM48_IE_MA_BEFORE,
  - fix position of the Mobile Allocation (after time) IE.

This problem was uncovered by (not yet merged) TTCN-3 test case
verifying handling of the hopping parameters [2].  This change
makes it pass.

[1] I43ef66c109b107ebcaa1cb6197637701b13b3787
[2] BSC_Tests.TC_fh_params_handover_cmd

Change-Id: I7569eead9760b6fd4bb91fc2d8d0b8200bebe374
Related: SYS#4868, OS#4545
2020-09-03 10:57:44 +00:00
Neels Hofmeyr 4829015b55 debug log: add RR Release cause code to the log
Change-Id: I53d524b5521804d80463079fa2e20221ee1b15f1
2020-08-13 12:54:08 +00:00
Philipp Maier e8296d285b gsm_04_08_rr: block EMERGENCY SETUP when EMERGENCY CALLS are denied
If the BSC configuration is set up to deny emergency calls, make sure
that an EMERGENCY SETUP will not be passed to the MSC, instead ensure
that the call is released.

Change-Id: Ia6eb38370ce4165d221d2ffbe1cd105c0628313c
Related: OS#4548
2020-08-12 18:07:33 +00:00
Pau Espin 388ed58482 Move struct gsm_bts: gsm_data.* => bts.*
Place all code related to the object into the related file.

Having all the data model in one file made sense in early stage of
development to make progress quickly, but nowadays it hurts more than
helps, due to constantly growing size and more and more bits being
added to the model, gaining in complexity.

Currently, having lots of different objects mixed up in gsm_data.h is a hole
of despair, where nobody can make any sense were to properly put new stuff
in, ending up with functions related to same object in different files
or with wrong prefixes, declarations of non-existing functions, etc.
because people cannot make up their mind on strict relation to objects
in the data model.
Splitting them in files really helps finding code operating on a
specific object and helping with logically splitting in the future.

Change-Id: I00c15f5285b5c1a0109279b7ab192d5467a04ece
2020-07-18 21:45:32 +00:00
Neels Hofmeyr b523f54de4 RR Channel Release: pass Cause code from BSSMAP Clear to the BTS
In lchan.release, add 'cause_rr', and set RR Channel Release message's cause
value to lchan.release.cause_rr.

In lchan_release(), do not set lchan.release.rsl_error_cause to the RR cause
value, these are unrelated. Store in new lchan.release.cause_rr instead. The
rsl_error_cause is apparently only used for logging, except for one place in
lchan_fsm_wait_activ_ack() that compares it to RSL_ERR_RCH_ALR_ACTV_ALLOC, so
there should not be a functional difference by this fix.

Propagate the BSSMAP Clear Command cause to the RR Channel Release:

Add struct gscon_clear_cmd_data as event data for GSCON_EV_A_CLEAR_CMD -- so
far it sent the is_csfb flag, add the gsm0808_cause; invoking the event happens
in bssmap_handle_clear_cmd().

Adjust event handling in gscon_fsm_allstate(); there, pass the cause to
gscon_release_lchans(). In gscon_release_lchans(), pass the cause to
gscon_release_lchan(), and then lchan_release(), which sets the new
lchan.release.cause_rr to the passed cause value.

As soon as the lchan FSM enters the proper state, it calls
gsm48_send_rr_release(). There, set the cause value in the encoded message to
lchan.release.cause_rr.

Interworking with osmo-msc: so far, osmo-msc fails to set the Clear Command
cause code for normal release, it just passes 0 which amounts to
GSM0808_CAUSE_RADIO_INTERFACE_MESSAGE_FAILURE. Before this patch, osmo-bsc
always sent GSM48_RR_CAUSE_NORMAL in the RR Channel Release, and after this
patch it will receive 0 == GSM0808_CAUSE_RADIO_INTERFACE_MESSAGE_FAILURE from
osmo-msc and more accurately translate that to GSM48_RR_CAUSE_PROT_ERROR_UNSPC.
This means in practice that we will now see an error cause in RR Channel
Release instead of GSM48_RR_CAUSE_NORMAL when working with osmo-msc. For
changing osmo-msc to send GSM0808_CAUSE_CALL_CONTROL instead (which translates
to GSM48_RR_CAUSE_NORMAL), see OS#4664 and change-id
I1347ed72ae7d7ea73a557b866e764819c5ef8c42 (osmo-msc).

A test for this is in Ie6c99f28b610a67f2d59ec00b3541940e882251b
(osmo-ttcn3-hacks).

Related: SYS#4872
Change-Id: I734cc55c501d61bbdadee81a223b26f9df57f959
2020-07-16 12:03:19 +00:00
Neels Hofmeyr 954ee0a4b8 RR Release Cell selection IE: fix repeated EARFCNs encoding
3GPP 44.018 10.5.2.1e defines the EARFCNs encoded in the 'Cell selection
indicator after release of all TCH and SDCCH IE' as follows:

  <Cell Selection Indicator after release of all TCH and SDCCH value part> ::=
  [...]
  | 011 { 1 <E-UTRAN Description : < E-UTRAN Description struct >> } ** 0

So after a 3-bit discriminator of '3' there can be multiple E-UTRAN
Descriptions, and each of them starts with a '1' bit to indicate that another
item follows. Finally there is a '0' bit to indicate the list end.

Before this patch, osmo-bsc only encoded the first '1' bit, and failed to
repeat this before each following E-UTRAN Description. Fix that by moving the
'1' encoding into the loop.

The final '0' was missing. Add it.

With these changes, adjust the size calculation in
CELL_SEL_IND_AFTER_REL_MAX_BITS to match.

Also fix CELL_SEL_IND_AFTER_REL_MAX_BYTES by using OSMO_BYTES_FOR_BITS()
instead of the inaccurate (n/8)+1.

A test for this is in I882c5e1f70bcc4833fc837a95c900ce291919cc5
(osmo-ttcn3-hacks).

Related: SYS#4871 SYS#4872
Change-Id: I59e427e4ebb1c6af99b27a15c40fed82457ac8ab
2020-07-16 12:03:19 +00:00
Vadim Yanitskiy b842568039 gsm_04_08_rr: fix hopping parameters in RR Assignment Command
According to 3GPP TS 44.018, section 9.1.2.4, if at least one of
the Channel Description IEs indicates frequency hopping, one and
only one of the following IEs shall be present:

  - Mobile Allocation, after time (see 10.5.2.21);
  - Frequency List, after time (see 10.5.2.13).

For some reason, osmo-bsc includes the GSM48_IE_MA_BEFORE instead
of GSM48_IE_MA_AFTER - fix this.

According to section 9.1.2.6 of the same document, if any of the
Mobile Allocation IEs (before/after time) is present, then the
network must ensure that either the MS has already received the
the proper reference cell frequency list (CA), or that the Cell
Channel Description IE (see 10.5.2.1b) is present.

Without this IE, the phone I was using in my testing setup sends
RR Status message with cause #100 "conditional IE error".

Fortunately, we already have generate_cell_chan_list(), since we
also need to include the Cell Channel Description in SI Type 1.

Change-Id: I43ef66c109b107ebcaa1cb6197637701b13b3787
Related: SYS#4868, OS#4545, OS#4546
2020-07-03 03:53:10 +07:00
Neels Hofmeyr a87646cd84 use osmo_mobile_identity API everywhere
Depends: If4f7be606e54cfa1c59084cf169785b1cbda5cf5 (libosmocore)
Change-Id: I71c3b4c65dbfdfa51409e09d4868aea83225338a
2020-06-16 14:56:57 +02:00
Neels Hofmeyr 2c61245935 remove extract_sub(), add bsc_subscr_find_or_create_by_mi()
Use the new osmo_mobile_identity API to shed some code dup and simplify.
gsm48_paging_extract_mi() is now unused, drop.

(More refactoring to use osmo_mobile_identity follows in subsequent patch.)

Depends: If4f7be606e54cfa1c59084cf169785b1cbda5cf5 (libosmocore)
Change-Id: Id6cccaac64392b737b3bba8f3a22a88009adb23b
2020-06-16 14:56:57 +02:00
Alexander Chemeris 962cb637fc Return 0 from gsm0408_rcvmsg() if SCCP link is already closed.
Whether to forward the message or not to an SCCP connection is
an internal question for the GSM 04.08 code. Unlike errors with
the message decoding, memory allocation and other critical errors,
this not an error which should be reported to the caller.
abis_rsl_rx_rll() (the caller) shouldn't know about the message
routing decisions and should only care about actual errors.

This code path is hit in production very often because we frequently
receive a Classmark Change message from a phone right after the MSC
has shut the SCCP connection but before we close the lchan on the BTS.

Change-Id: I2d430ebc894a2345bebaa1841a75e94a3b45eae2
2020-05-29 20:03:26 +00:00
Martin Hauke a29affda98 Fix some typos
Fix typos and common misspellings in code comments and in the manual.

Change-Id: I46fc9d424620c77ae9ccf78b58081bd303386d7c
2019-11-13 22:10:41 +01:00
Harald Welte bbd0bfff17 SMSCB: Send ETWS primary warning message via all dedicated channels
As soon as we have received an ETWS primary notification message from
the CBC, we should transmit it as "RR Application Information" to all
dedicated channels.

Change-Id: I913d0237cffdcb95037da8489acef5f32a7fc02e
2019-09-06 23:09:54 +02:00
Daniel Willmann 1d5eda4b4c gsm_data.h: Remove unused variable from OpenBSC times
This variable does not seem to be used anywere in OsmoBSC, seems to be a
remnant from OpenBSC times.

Change-Id: I5e4aa352fa5f16f6ff64738f25afd1a844fa4fcb
2019-04-17 16:01:11 +00:00
Harald Welte 963763dfec Implement CSFB "Fast Return" Handling at RR RELEASE
When the MSC sends a BSSMAP CLEAR CMD containing a CSFB Indication IE,
it lets us know that the to-be-released connection related to a CSFB
call.

We as the BSC then subsequently should include the "Cell Selection
Indicator after release of all TCH and SDCCH" IE in the RR RELEASE
message sent to the MS/UE.  This IE contains the LTE neighbor cells
that we're configured to broadcast in si2quater.

That in turn will make sure the MS/UE can return very quickly to
the LTE cell.

Closes: OS#3777
Change-Id: Ibfbb87e2e16b05032ad1cb91c11fad1b2f76d755
Requires: libosmocore Id4bd7f7543f5b0f4f6f876e283bd065039c37646
Requires: libosmocore I0e101af316438b56d63d43fc2cb16d7caf563d07
Requires: libosmocore I8980a6b6d1973b67a2d9ad411c878d956fb428d1
2019-02-05 16:04:35 +01:00
Daniel Willmann 162626637f gsm_04_08: Free GSM subscr conn if paging response can't be matched
The current idea of calling gscon_release_lchans is not enough because
the conn is still present.
Insetad pretend we got a disconnect indication from the MSC which will
call gscon_release_lchans as well as terminate the conn state machine
which will clean up conn state as well.

Related: OS#3680
Change-Id: Iccf5f6864ffe238189907c4bb3ea333948621b4c
2018-12-06 19:51:21 +00:00
Pau Espin 77cd112993 gsm0408_rcvmsg: Release lchan if L3 fails to complete
gscon_release_lchans stub is added to gsm0408_test.c to make linker
happy.

Change-Id: I1743f9d5cd0fdbc0fb9afe7bcc0271c897915210
2018-11-21 17:59:06 +01:00
Neels Hofmeyr 5b1a7d1e9b lchan release: always Deact SACCH
If an lchan is being released and had a SACCH active, there is no reason to
omit the Deact SACCH message ever. All of the callers that passed
do_deact_sacch = false did so for no good reason.

Drop the do_deact_sacch flag everywhere and, when the lchan type matches and
SAPI[0] is still active, simply always send a Deact SACCH message.

The do_deact_sacch flag was carried over from legacy code, by me, mainly
because I never really understood why it was there. I do hope I'm correct now,
asserting that having this flag makes no sense.

Change-Id: Id3301df059582da2377ef82feae554e94fa42035
2018-11-14 16:16:30 +00:00
Neels Hofmeyr 478e991a78 fix: send RR Release (e.g. after BSSMAP Clear Cmd)
After commit [1], the code makes sure to disassociate lchan and conn before
invoking the lchan release. However, we only send RR Release if a conn is
present, which clearly is nonsense after [1].

[1] commit 8b818a01b0
    "subscr conn: properly forget lchan before release"
    Change-Id: I4fd582b41ba4599af704d670af83651d2450b1db

Manage sending of RR Release via a flag, set during invoking lchan release.

Add do_rr_release arg to lchan_release(), gscon_release_lchans(). In
lchan_fsm.c, send RR Release only if do_rr_release was passed true; do not care
whether a conn is still associated (because it won't ever be since [1]).

That way we can intelligently decide what release process makes sense (whether
the lchan terminates the subscriber connection or whether the connection goes
on at another lchan), and still disassociate lchan and conn early.

BTW, this problem wasn't caught by the stock OsmoBSC TTCN3 tests, because the
f_expect_chan_rel() don't care whether an RR Release happens or not. This is
being fixed by Ibc64058f1e214bea585f4e8dcb66f3df8ead3845.

So far this patch should fix BSC_Tests_LCLS.TC_lcls_connect_clear.

Related: OS#3413
Change-Id: I666b3b4f45706d898d664d380bd0fd2b018be358
2018-11-14 16:16:30 +00:00
Philipp Maier 3b9dcb3fc1 gsm_04_08: improve gsm48_multirate_config()
The function gsm48_multirate_config() generates the multirate
configuration IE, that is sent via RSL to configure the active set of
AMR codecs inside the BTS. The function already works, but it does not
check the input data for consistancy. Lets add some consistancy check to
make sure that inconsistant parameters are rejected. Also allow the
output pointer to be NULL, so that the function can be used to perform
a dry run to be able to verify parameters.

- Check for invalid / inconsistant configuration parameters
- Perform a dry-run when lv pointer is set to NULL

Change-Id: I06beb7dd7236c81c3a91af4d09c31891f4b910a4
Related: OS#3529
2018-10-24 09:22:41 +02:00
Neels Hofmeyr e2209c20c5 Implement RR Classmark Enquiry
If the MSC sends a BSSMAP Classmark Request, send an RR Classmark Enquiry to
the MS.

(The reverse direction, i.e. sending a BSSMAP Classmark Update back to the MSC,
is already implemented.)

Related: OS#3043 (A5/3 encryption)
Related: osmo-ttcn3-hacks Idaab4d568cf986b4897ba008f6262c839d1592fb
Change-Id: If5db638fd6e8d9c2ef9e139e99f0fabe1ef16ddf
2018-09-18 14:34:32 +02:00