Commit Graph

19 Commits

Author SHA1 Message Date
Neels Hofmeyr d77bd741c1 neighbor vty: identify neighbors by gsm0808 cell id
For deleting neighbor entries and for triggering manual handovers, it is useful
to identify neighbors by the gsm0808_cell_id, instead of just by ARFCN+BSIC.

This is not a hard requirement, since BTS+ARFCN+BSIC fully identifies a
neighbor. But consider these contrived examples of the situation before this
patch:

 # bts 0
 # neighbor cgi 001 01 23 42
 # no neighbor cgi 001 01 23 42
   % No such command
 # no neighbor bts 5
   (manually looked up that BTS 5 has above CGI)

 # neighbor lac 42 arfcn 23 bsic 5
 # do handover any to lac 42
   % No such command
 # do handover any to arfcn 23 bsic 5
   (if multiple cells have the same ARFCN+BSIC, the identification is not unique)

So this fills a gap, if only to help debugging / analyzing handover operations.

Change-Id: I198fe7055d1e09b128693eb51276e3d8cde1c0ba
2018-10-31 00:23:39 +01:00
Neels Hofmeyr 34c881a811 cosmetic: rename osmo_bsc_api.c to gsm_08_08.c
Change-Id: I91922f557072d0fb8cfe213a8a7b50f3bb23dea0
2018-07-28 12:18:23 +02:00
Neels Hofmeyr 8757f42c8e cosmetic: dissolve bsc_api.c
gsm0808_page() is just a thin wrapper for rsl_paging_cmd(), the only caller is
page_ms() from paging.c. Directly call rsl_paging_cmd() instead.

Move gsm0808_cipher_mode() to the only caller in osmo_bsc_bssap.c, make static.

Change-Id: Ib7ce026b52d4ba3e53a8b2824e74ea92432c48c5
2018-07-28 12:18:23 +02:00
Neels Hofmeyr ac85b34476 lchan_fsm: split off lchan_rtp_fsm, establish RTP a bit earlier
Change-Id: Id7a4407d9b63be05ce63f5f2768b7d7e3d5c86fb
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
Neels Hofmeyr 596c402835 add gsm_timers, for Tnnn definitions usable by FSMs
Change-Id: If212fcd042051b6fa53484254223614c5b93a9c6
2018-07-28 12:18:23 +02:00
Neels Hofmeyr 6242742d20 rename gsm_04_08_utils.[hc] to gsm_04_08_rr
"utils" suggests thin helpers to aid using a proper API, while this .c file
actually *is* the proper RR API. Rename from "utils" to "rr".

Change-Id: I0ffff63d57f03cb324df8e40e41caea5b55a2c85
2018-07-28 12:18:23 +02:00
Neels Hofmeyr 19bed23065 inter-BSC HO: add neighbor_ident API to manage neighbor-BSS-cells
Depends: Ia71ba742108b5ff020997bfb612ad5eb30d04fcd (libosmocore)
Change-Id: I0153d7069817fba9146ddc11214de2757d7d37bf
2018-07-28 12:18:23 +02:00
Philipp Maier 844876f8d5 codec_pref: move match_codec_pref() to separate c-file and add unit-test
At the moment there are three sources that may advertise a list of
supported audio codec/rate settings. There is the MS that advertises
advertises a speech codec list and the MSC that sends a channel type
information element over A and there are also settings in the bsc
configuration file that may restrict the codec/rate types that are
allowed to use.

The function match_codec_pref() looks at all of the three buckets and
selects a codec that satisfies all three. This is already a somewhat
complicated process, overit is very isolated, so lets give it its own
c-file.

Due to the lack of unit-tests it is very hard to make changes here so
lets add also unit-test to make sure that regressions are catched early.

- Put match_codec_pref() and all its helper functions into a separate
  c-file.
- Add a unit test.

Change-Id: Iabedfdcec8b99a319f2d57cbea45c5e36c7b6e29
Related: OS#3361
2018-07-22 06:16:11 +00:00
Neels Hofmeyr 958f259f95 dissolve libbsc: move all to src/osmo-bsc, link .o files
Move all of libbsc/ into osmo-bsc/, and separate/move some implementations to
allow linking from utils/* and ipaccess/* without pulling in unccessary
dependencies.

Some utilities use gsm_network and gsm_bts structs, which already include data
structures for fairly advanced uses. Move initialization that only osmo-bsc
needs into new bsc_network_init() and bsc_bts_alloc_register() functions, so
that the leaner tools can use the old gsm_* versions without the need to link
everything (e.g. handover and lchan alloc code).

In some instances, there need to be stubs if to cut off linking "just before
the RSL level" and prevent dependencies from creeping in.
- abis_rsl_rcvmsg(): the only program currently interpreting RSL messages is
  osmo-bsc, the utils are merely concerned with OML, if at all.
- paging_flush_bts(): ip.access nanobts models call this when the RSL link is
  dropped. Only osmo-bsc actually needs to do anything there.
- on_gsm_ts_init(): the mechanism to trigger timeslot initialization is related
  to OML, while this action to take on init would pull in RSL dependencies.
utils/ and ipaccess/ each have a stubs.c file to implement these stubs. Tests
implement stubs inline where required.

From src/utils/, src/ipaccess/ and tests/*/, link in .o files from osmo-bsc/.
In order for this to work, the osmo-bsc subdir must be built before the other
source trees. (An alternative would be to include the .c files as sources, but
that would re-compile them in every source tree. Not a large burden really, but
unless linking .o files gives problems, let's have the quicker build.)

Minor obvious cleanups creep in with this patch, I will not bother to name them
individually now unless code review asks me to.

Rationale:

1) libbsc has been separate to use it for osmo-nitb and osmo-bsc in the old
openbsc.git. This is no longer required, and spreading over libbsc and osmo-bsc
is distracting.

2) Recently, ridiculous linking requirements have made adding new functions
cumbersome, because libbsc has started depending on osmo-bsc/*.c
implementations: on gscon FSM and bssap functions. For example, neither
bs11_config nor ipaccess-config nor bts_test need handover_cfg or BSSMAP
message composition. It makes no sense to link the entire osmo-bsc to it, nor
do we want to keep adding stubs to each linking realm.

Change-Id: I36a586726f5818121abe54d25654819fc451d3bf
2018-06-07 19:09:06 +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
Neels Hofmeyr d23ce86c25 drop libcommon-cs completely
Change-Id: I07d4a48af3154ee4d904686f230a51b8b8a94ff9
2018-02-14 12:55:45 +01:00
Neels Hofmeyr 421059a2c0 drop libcommon completely, move remaining files to libbsc
Move gsm_data.c and handover_cfg.c to libbsc, where they belong.

This leaves libcommon utterly empty, drop it.

Change-Id: I6178061fa30c7e1a4c22c29d3c8f508b1033569f
2018-02-14 12:54:38 +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
Harald Welte d9956d91ba Remove dead code left over from NITB split
There still is a lot of dead code that we inherited from the NITB
days, let's remove more of it.

libtrau will be re-introduced as part of osmo-mgw later.

Change-Id: I8e0af56a158f25a4f1384d667c03eb20e72df5b8
2017-12-19 17:53:13 +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 7b656884cf split off osmo-bsc: remove files, apply build
Change-Id: I64d84c52f6e38e98144eb9be8f0ab82e0e1f6cca
2017-08-30 14:11:25 +02:00
Philipp Maier 39f62bbcbf Implement AoIP, port to M3UA SIGTRAN (large addition and refactoring)
This was originally a long series of commits converging to the final result
seen in this patch. It does not make much sense to review the smaller steps'
trial and error, we need to review this entire change as a whole.

Implement AoIP in osmo-msc and osmo-bsc.

Change over to the new libosmo-sigtran API with support for proper
SCCP/M3UA/SCTP stacking, as mandated by 3GPP specifications for the IuCS and
IuPS interfaces.

From here on, a separate osmo-stp process is required for SCCP routing between
OsmoBSC / OsmoHNBGW <-> OsmoMSC / OsmoSGSN

jenkins.sh: build from libosmo-sccp and osmo-iuh master branches now for new
M3UA SIGTRAN.

Patch-by: pmaier, nhofmeyr, laforge
Change-Id: I5ae4e05ee7c57cad341ea5e86af37c1f6b0ffa77
2017-08-30 14:09:31 +02:00
Neels Hofmeyr 218e4b4aa0 move openbsc/* to repos root
This is the first step in creating this repository from the legacy openbsc.git.

Like all other Osmocom repositories, keep the autoconf and automake files in
the repository root. openbsc.git has been the sole exception, which ends now.

Change-Id: I9c6f2a448d9cb1cc088cf1cf6918b69d7e69b4e7
2017-08-27 03:52:43 +02:00