Commit Graph

15 Commits

Author SHA1 Message Date
Harald Welte 6c8ca97546 Support building with -Werror=strict-prototypes / -Werror=old-style-definition
Unfortunately "-std=c99" is not sufficient to make gcc ignore cold that
uses constructs of earlier C standards, which were abandoned in C99.

See https://lwn.net/ml/fedora-devel/Y1kvF35WozzGBpc8@redhat.com/ for
some related discussion.

Change-Id: Ic92aa70d569778a776f4c5d24c455f71fd50b61b
2022-11-10 00:28:46 +00:00
Neels Hofmeyr b26dd1ebf6 drop some unused members and function decls
Change-Id: I0de2c8a3ee6c693a5a321f0ea2a8a75fbe64a1c2
2020-09-03 01:07:15 +02:00
Neels Hofmeyr 6a8955b741 drop all BSC originated USSD notification features
The BSC is the wrong network component to originate USSD messaging, as can be
seen in the hacks in the USSD code: for example, the BSC would send a CM
Service Accept message as if an MSC had accepted the connection, dispatch a
USSD and directly send some RR release message (without proper tear down
messaging like the lchan_fsm does these days). This made sense in the osmo-nitb
world, but by now we are aiming for solid 3GPP compliance. The BSC shall not
originate USSD messages.

Deprecate all VTY and CTRL commands related to USSD:
VTY
 [no] bsc-welcome-text
 [no] bsc-msc-lost-text
 [no] bsc-grace-text
 [no] missing-msc-text
 (the commands with 'no' are ignored, without 'no' lead to an error)
CTRL
 ussd-notify-v1

Drop (already unused) ussd.h.
Drop gsm_04_80.h, gsm_04_80_utils.c, and all calling code.

Drop "RF grace" notification, where osmo-bsc was able to notify active
subscribers that the RF was being turned off.

Change-Id: Iaef6f2e01b4dbf2bff0a0bb50d6851f50ae79f6a
2020-05-29 20:16:40 +00:00
Neels Hofmeyr 5cda1d01b4 drop IMSI filter and libfilter completely
Filtering by IMSI in osmo-bsc is a legacy use case with questionable
usefulness. Remove.

Do not keep deprecated VTY commands: those could be dangerous, since
(presumably non-existing) users might assume that the filtering would still be
in place. Rather fail to start osmo-bsc for config with an IMSI ACL.

The IMSI filtering did, if present, provide the logging with an IMSI to print
for the bsc_subscriber. TMSIs should have ended up in logging likewise, which
has never been implemented. The proper way to learn the IMSI would be by the
Common Id message from the MSC. Furthermore, the upcoming MSC pooling feature
will extract the mobile identity again, and will hence make sure that both IMSI
and TMSI identities, as available, end up in the bsc_subscriber and will be
logged again.

So long, IMSI ACL, and thanks for all the fish.

Change-Id: I89727af5387e8360362e995fdee959883c37d89a
2020-05-27 01:56:06 +02:00
Pau Espin 120746e66f gsm_08_08.c: Mark func bsc_find_msc() static
Its currently only used by bsc_compl_l3() in same file.

Change-Id: I7273a9452dbc4c1285cfa69269fa36ab09551d89
2019-10-03 17:22:11 +02:00
Neels Hofmeyr b5ce49f872 cosmetic: reduce bsc_api.h
Remove as much as possible from bsc_api.h. Use '#pragma once'. Tweak head
comment.

BSC_API_CONN_POL_{ACCEPT,REJECT}: only user is static complete_layer3(), just
use a bool return value instead.

msc_connected(): only used in osmo_bsc_api.c, make static there.

Instead of including gsm_data.h, declare structs opaquely, include stdint.h.
codec_pref_test.c used this as indirect gsm_data.h include via osmo_bsc.h,
include gsm_data.h there directly.

osmo_bsc.h: instead of including bsc_api.h, declare opaque structs.

gsm_04_08_rr.h: declare opaque structs to replace indirect include of
gsm_data.h.

Change-Id: Ia9c0f9828317236048e40ec9ecf9990592e2190a
2018-07-28 12:18:23 +02:00
Neels Hofmeyr 31f525e756 large refactoring: use FSMs for lchans; add inter-BSC HO
Add FSMs:

- timeslot_fsm: handle dynamic timeslots and OML+RSL availability.
- lchan_fsm: handle an individual lchan activation, RTP stream and release,
  signal the appropriate calling FSMs on success, failure, release.
- mgw_endpoint_fsm: handle one entire endpoint with several CI.
- assignment_fsm: BSSMAP Assignment Request.
- handover_fsm: all of intra, inter-MO and inter-MT handover.

Above FSMs absorb large parts of the gscon FSM. The gscon FSM was surpassing
the maximum amount events (32), and it is more logical to treat assignment,
handover and MGW procedures in separate FSMs.

- Add logging macros for each FSM type:
  - LOG_TS()
  - LOG_LCHAN()
  - LOG_MGWEP(), LOG_CI()
  - LOG_ASSIGNMENT()
  - LOG_HO()
  These log with the osmo_fsm_inst where present.
  New style decision: logging without a final newline char is awkward,
  especially for gsmtap logging and when other logs interleave LOGPC() calls;
  we have various cases where the final \n goes missing, and also this invokes
  the log category checking N times instead of once.
  So I decided to make these macros *always* append a newline, but only if
  there is no final newline yet. I hope that the compiler optimizes the
  strlen() of the constant format strings away. Thus I can log with or without
  typing "\n" and always get an \n termination anyway.

General:

- replace osmo_timers, state enums and program-wide osmo_signal_dispatch()
  with dedicated FSM timeouts, states and events.

- introduce a common way to handle Tnnn timers: gsm_timers.h/.c: struct T_def.
  These can be used (with some macro magic) to define a state's timeout once,
  and not make mistakes for each osmo_fsm_inst_state_chg().

Details:

bsc_subscr_conn_fsm.c:

- move most states of this FSM to lchan_fsm, assignment_fsm, handover_fsm and
  mgw_endpoint_fsm.

- There is exactly one state for an ongoing Assignment, with all details
  handled in conn->assignment.fi. The state relies on the assignment_fsm's
  timeout.

- There is one state for an ongoing Handover; except for an incoming Handover
  from a remote BSS, the gscon remains in ST_INIT until the new lchan and conn
  are both established.

- move bssmap_add_lcls_status() to osmo_bsc_lcls.c

abis_rsl.c:

- move all dynamic timeslot logic away into timeslot_fsm. Only keep plain send/receive functions in
  abis_rsl.c

- reduce some rsl functions to merely send a message, rename to "_tx_".
  - rsl_ipacc_mdcx(): add '_tx_' in the name; move parts that change the lchan state out into the
    lchan_fsm, the lchan->abis_ip.* are now set there prior to invoking this function.

- move all timers and error/release handling away into various FSMs.

- tweak ipa_smod_s_for_lchan() and ipa_rtp_pt_for_lchan() to not require an
  lchan passed, but just mode,type that they require. Rename to
  ipacc_speech_mode*() and ipacc_payload_type().

- add rsl_forward_layer3_info, used for inter-BSC HO MO, to just send the RR
  message received during BSSMAP Handover Command.

- move various logging to LOG_LCHAN() in order to log with the lchan FSM instance.
  One drawback is that the lchan FSM is limited to one logging category, i.e. this moves some logging
  from DRR to DRSL. It might actually make sense to combine those categories.

- lose LOGP...LOGPC logging cascades: they are bad for gsmtap logging and for performance.

- handle_classmark_chg(): change logging, move cm2 len check out of the cm3 condition (I hope that's
  correct).

- gsm48_send_ho_cmd(): split off gsm48_make_ho_cmd() which doesn't send right away, so that during
  inter-bsc HO we can make an RR Handover Command to send via the MSC to the remote BSS.

assignment_fsm.c:

- the Chan Mode Modify in case of re-using the same lchan is not implemented
  yet, because this was also missing in the previous implementation (OS#3357).

osmo_bsc_api.c:

- simplify bsc_mr_config() and move to lchan_fsm.c, the only caller; rename to
  lchan_mr_config(). (bsc_mr_config() used to copy the values to mr_bts_lv
  twice, once by member assignment and then again with a memcpy.)

- During handover, we used to copy the MR config from the old lchan. Since we
  may handover between FR and HR, rather set the MR Config anew every time, so
  that FR rates are always available on FR lchans, and never on HR lchans.

Depends: I03ee7ce840ecfa0b6a33358e7385528aabd4873f (libosmocore),
         I1f2918418c38918c5ac70acaa51a47adfca12b5e (libosmocore)
Change-Id: I82e3f918295daa83274a4cf803f046979f284366
2018-07-28 12:18:23 +02:00
Harald Welte 3561bd4897 introduce an osmo_fsm for gsm_subscriber_connection
In the current implementation of osmo-bsc, the subscriber connection is
not handled (very) statefully. However, there is some state keeping in the
code that handles the mgcp connection, but there are still to much loose ends
which allow odd situations to happen, which then lead severe error situations
(see also closes tags at the end) This commit adds a number of improvements
to fix those problems.

- Use an osmo-fsm to control the gsm_subscriber_connection state and
  make sure that certain operations can only take place at certain states
  (e.g let connection oriented SCCP traffic only pass when an SCCP connection
  actually exists.

  Remove the old osmo_bsc_mgcp.c code. Use the recently developed MGCP client
  FSM to handle the MGCP connections.

  Also make sure that stuff that already works does not break. This in
  particular refers to the internal handover capability and the respective
  unit-tests.

  See also OS#2823, OS#2768 and OS#2898

- Fix logic to permit assignment to a signalling channel. (OS#2762)

- Introduce T993210 to release lchan + subscr_conn if MSC fails to respond

  The GSM specs don't have an explicit timer for this, so let's introdcue
  a custom timer (hence starting with 99).

  This timeout catches the following situation:
  * we send a SCCP CR with COMPL_L3_INFO from the MS to the MSC,
  * the MSC doesn't respond (e.g. SCCP routing failure, program down, ...)

  The MS is supposed to timeout with T3210, 3220 or 3230.  But the BSC
  shouldn't trust the MS but have some timer on its own.

  SCCP would have a timer T(conn est), but that one is specified to be
  1-2min and hence rather long.

  See also: OS#2775

- Terminate bsc_subscr_conn_fsm on SCCP N-DISC.ind from MSC

  If the MSC is disconnecting the SCCP channel, we must terminate the FSM
  which in turn will release all lchan's and other state.

  This makes TC_chan_rel_hard_rlsd pass, see also OS#2731

  As a side-effect, this fixes TC_chan_act_ack_est_ind_refused(),
  where the MSC is answering with CREF to our CR/COMPL_L3.

- Release subscriber connection on RLL RELEASE IND of SAPI0 on main DCCH

  The subscriber connection isn't really useful for anything after the
  SAPI0 main signalling link has been released.  We could try to
  re-establish, but our best option is probably simply releasing the
  subscriber_conn and anything related to it.

  This will make TC_chan_rel_rll_rel_ind pass, see also OS#2730

This commit has been tested using the BSC_Tests TTCN3 testsuit and the
following tests were passed:

TC_chan_act_noreply
TC_chan_act_ack_noest
TC_chan_act_ack_est_ind_noreply
TC_chan_act_ack_est_ind_refused
TC_chan_act_nack
TC_chan_exhaustion
TC_ctrl
TC_chan_rel_conn_fail
TC_chan_rel_hard_clear
TC_chan_rel_hard_rlsd
TC_chan_rel_a_reset
TC_rll_est_ind_inact_lchan
TC_rll_est_ind_inval_sapi1
TC_rll_est_ind_inval_sapi3
TC_rll_est_ind_inval_sacch
TC_assignment_cic_only
TC_assignment_csd
TC_assignment_ctm
TC_assignment_fr_a5_0
TC_assignment_fr_a5_1_codec_missing
TC_assignment_fr_a5_1
TC_assignment_fr_a5_3
TC_assignment_fr_a5_4
TC_paging_imsi_nochan
TC_paging_tmsi_nochan
TC_paging_tmsi_any
TC_paging_tmsi_sdcch
TC_paging_tmsi_tch_f
TC_paging_tmsi_tch_hf
TC_paging_imsi_nochan_cgi
TC_paging_imsi_nochan_lac_ci
TC_paging_imsi_nochan_ci
TC_paging_imsi_nochan_lai
TC_paging_imsi_nochan_lac
TC_paging_imsi_nochan_all
TC_paging_imsi_nochan_plmn_lac_rnc
TC_paging_imsi_nochan_rnc
TC_paging_imsi_nochan_lac_rnc
TC_paging_imsi_nochan_lacs
TC_paging_imsi_nochan_lacs_empty
TC_paging_imsi_a_reset
TC_paging_counter
TC_rsl_drop_counter
TC_classmark
TC_unsol_ass_fail
TC_unsol_ass_compl
TC_unsol_ho_fail
TC_err_82_short_msg
TC_ho_int

Authors:
Harald Welte <laforge@gnumonks.org>
Philipp Maier <pmaier@sysmocom.de>
Neels Hofmeyr <neels@hofmeyr.de>

Closes: OS#2730
Closes: OS#2731
Closes: OS#2762
Closes: OS#2768
Closes: OS#2775
Closes: OS#2823
Closes: OS#2898
Closes: OS#2936
Change-Id: I68286d26e2014048b054f39ef29c35fef420cc97
2018-03-16 18:49:47 +00:00
Harald Welte 519c7e1d42 Structural reform: Get rid of osmo_bsc_sccp_con
There was always a 1:1 correspondence between gsm_subscriber_connection
and osmo_bsc_sccp_con, so there's really no point in having two separate
dynamically allocated data structures with pointers back and forth and
another linked list around.

Let's merge osmo_bsc_sccp_con into gsm_subscriber_connection for
simplicity.

The resulting code might not be elegant in places, but I've tried to
do only the most simple changes in this patch, while further
simplifications can be done in later subsequent patches.

As a side-effect, this patch also fixes lchan clearing if the MSC
(or the local SCCP provider) hard-disconnects the SCCP connection.

Change-Id: Idd2b733477ee90d24dec369755a00f1c39c93f39
2018-02-19 08:20:35 +00:00
Harald Welte ea0c3203db osmo-bsc: Move user plane/voice related bits into sub-structure
This clarifies which members of the struct are for what.

Change-Id: I618822e6f2d48adce25f9df5c25acbce7c858412
2017-12-19 18:58:51 +01:00
Harald Welte ca494f385e osmo_bsc.h: document every field in 'struct osmo_bsc_sccp_con'
Change-Id: I674ed61a22fad5cc09c45128dbc73474893aefb6
2017-12-19 18:58:51 +01:00
Harald Welte 95464c78fd Remove unused struct osmo_bsc_sccp_con member sccp_queue_size
Change-Id: Ibc4b8f3776c35df7e81252efb78ec740a371de7f
2017-12-19 18:58:22 +01:00
Harald Welte e94d7d1bdf remove libosmo-sccp dependency for osmo-bsc
libosmo-sccp is the old sccp-lite-focused SCCP implementation that we
used before libosmo-sigtran was created.  The new osmo-bsc in this
repository is using libosmo-sigtran and shouldn't be using parts of
libosmo-sccp anymore.

We only keep it around in configure.ac and Makefile.am for osmo-bsc_nat,
which is not even built in this repository anymore (or 'again yet'?)

Change-Id: I8f274be7d196cd7a5b1ec9ada949130fb06e984d
2017-12-19 17:53:14 +00:00
Philipp Maier 39c609b7c9 mgcp: use osmo-mgw to switch RTP streams
osmo-bsc currently negotiates the RTP stream directly with the
BTS and reports back the RTP IP/Port on the BTS. This works fine
for a single BTS, but for Handover the port/ip pointing to the
MSC side must not change, so an entity in between the BTSs and
the MSC is required.

Integrate the mgcp-client and use osmo-mgw to switch the RTP
streams.

Depends: osmo-mgw Ib5fcc72775bf72b489ff79ade36fb345d8d20736
Depends: osmo-mgw I44b338b09de45e1675cedf9737fa72dde72e979a
Depends: osmo-mgw I29c5e2fb972896faeb771ba040f015592487fcbe

Change-Id: Ia2882b7ca31a3219c676986e85045fa08a425d7a
2017-11-07 20:57:51 +00:00
Neels Hofmeyr c01647914b move include/openbsc to include/osmocom/bsc
Change-Id: I39e7b882caa98334636d19ccd104fd83d07d5055
2017-09-06 16:26:13 +02:00