Commit Graph

25 Commits

Author SHA1 Message Date
Pau Espin 8e9f40a912 Use OSMO_FD_* instead of deprecated BSC_FD_*
New define is available since libosmocore 1.1.0, and we already require
1.3.0, so no need to update dependenices.
Let's change it to avoid people re-using old BSC_FD_* symbols when
copy-pasting somewhere else.

Change-Id: Ia5a656567d212fa265aef1375d714d0c5fee5dd6
2020-07-15 18:38:11 +02:00
Harald Welte 1626f90946 Re-introduce support for IPA-encapsulated MGCP
Old osmo-bsc-sccplite already supported this, but in the migration
over to libosmo-sigtran and to real 3GPP AoIP, this functionality
got lost.

We now create a UDP proxy socket. Any MGCP commands received via IPA
from MSC (or rather: bsc_nat) are retransmitted to the MGW via UDP on
this socket.  Any responses back from the MGW received on the UDP
socket are retransmitted back to MSC/bsc_nat as MGCP inside the IPA
multiplex.

Closes: OS#2536
Change-Id: I38ad8fa645c08900e0e1f1b4b96136bc6d96b3ab
2019-06-18 18:09:26 +00:00
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
Neels Hofmeyr be1131df42 HO: fix recovery from failed handover
Do not instruct the MGW to move the RTP to the new lchan before we have
received a HANDOVER DETECT.

Before:

  Chan Activ
  Chan Activ Ack
  IPACC-CRCX
   -ACK
  IPACC-MDCX
   -ACK
  MGCP MDCX --> MGW
  ...
  HANDOVER DETECT
  Call continues on new lchan

In above sequence, if the HANDOVER DETECT times out, the MGW has moved to the
new lchan which never becomes used and is released. Furthermore, from the IPACC
MDCX until the HANDOVER DETECT, the RTP stream would break off momentarily.

After:

  Chan Activ
  Chan Activ Ack
  IPACC-CRCX
   -ACK
  IPACC-MDCX
   -ACK
  ...
  HANDOVER DETECT
  MGCP MDCX --> MGW
  Call continues on new lchan

If the HANDOVER DETECT times out, the call happily continues on the old lchan.

This change is inspired by Ivan Kluchnikov's HO work, who implemented a similar
fix in the openbsc.git codebase (branch fairwaves/master-rebase): his patch
moves ipacc_mdcx() to connect RTP to the new lchan from switch_for_handover()
(which triggered on S_ABISIP_CRCX_ACK, i.e. creation of the new lchan) to later
on in ho_detect() a.k.a. the S_LCHAN_HANDOVER_DETECT signal handler:
http://git.osmocom.org/openbsc/commit/?h=fairwaves/master-rebase&id=9507a7a1ea627e07370c9d264816bb190b3b91b8

This patch does essentially the same: remove the mgcp_handover() call from the
MDCX-ACK handling (creation of the new lchan), and add a signal handler for
S_LCHAN_HANDOVER_DETECT to osmo_bsc_mgcp.c to effect the MGW switchover.

Note, it would have been possible to call mgcp_handover() directly from rx of
the HANDOVER DETECT message, but that produces linking fallout in some utils/
projects, which then need to link the mgcp code as well. That is because those
aren't properly separated from the more complex parts of libbsc. Using the
signal is a bit bloaty, but saves the linking hell for now. I've faced a
similar problem twice recently, it would pay off to separate out the simpler
utils/ and ipaccess/ tools so that they don't need to link all of libbsc and
osmo-bsc, at some point (TM).

Change-Id: Iec58c5fcc5697f1775da7ec0111135108ed1fc8f
2018-01-19 16:03:15 +01:00
Neels Hofmeyr 9af36d7844 osmo_bsc_mgcp: cosmetic: introduce mgcp_init(), soak up fsm init
A subsequent patch will add registration of a signal; cosmetically prepare by
creating a common mgcp_init() function. It makes sense for the FSM registration
to move to it.

Change-Id: I510e1081171706eb3d9fb2db50a9aa4f768929b5
2018-01-19 16:03:15 +01:00
Philipp Maier f56a28d1c2 cosmetic: mgcp: remove duplicate logging
do not print an additional log lines when the mgcp FSM gets
halted. This is already done by osmo-fsm

Change-Id: I5aebbcacb68eab3c6afb19991dbf63a02524e4d7
2018-01-10 11:12:12 +00:00
Philipp Maier f9ca0204c4 mgcp: log file and line of calls to handle_error()
When the FSM runs into an error condition handle_error() is called with
a cause code. The information about the error is then printed by handle_error(),
by this we do not get the sourcecode line of the location where the error
actually happend.

Convey the source code line number of the actual error in handle_error()

Change-Id: Ifa7f2a655474826630988572616cd26e1e2f3464
2018-01-10 11:11:53 +00:00
Philipp Maier 57d4fe7157 mgcp: validate rtp connection data in MGW response (ip/port)
Currently the pasing results from the RTP ip/port are fed into
inet_addr without checking the results.

Check the return code of inet_addr to be sure that the IP-Address
got properly decoded.

Change-Id: I1d0aa7e9b8480e1bef57269e3904399cb99815bb
2017-12-20 11:57:19 +01:00
Philipp Maier 75f2c8d47f mgcp: cancel transactions on timeout
when a transaction to the MGW times out, then the context
information is freed. Unfortunately the client is not informed
about this and will try to execute the callback anyway.

explicitly cancel the transaction in order to prevent access
to already freed data structures.

Change-Id: I40794dff7d10e2b6a96863a2da7e9fbd5662a1bf
2017-12-20 11:48:18 +01:00
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
Philipp Maier eb79614f4e mgcp: cosmetic fixups
- use unique enum/struct fsm struct names
- use macro to shift bits in FSM description
- use OSMO_STRINGIFY to generate the state names
- remove duplicate logging of states and events
- remove unnecessary space in log strings
- prefix hexadecimal enpoint ids with
- remove unnecessary log messages
- rename bsc_mgcp_cause_codes_str to bsc_mgcp_cause_codes_names

Change-Id: I663e03046cde3c786af72d15681bf7497330d7f9
2017-12-10 14:22:41 +00:00
Philipp Maier f4d0889abb cosmetic: use fsm pointer from parameter list
the parameter list of osmo-fsm callbacks contains a pointer
to the fsm instance. Use this pointer instead of reaching
out for mgcp_ctx->fsm.

Change-Id: I05ff62e7e2de64c2dbf5ea2736f5e58faf16df0b
2017-12-01 13:36:30 +01:00
Philipp Maier a89e163e4c cosmetic: correct sourcecode formatting
add missing line break

Change-Id: Ia117e4099046fefcf35ccb94400554062e667869
2017-12-01 13:36:30 +01:00
Philipp Maier e941f88ea1 cosmetic: add missing log prefix
the log messages have prefixes that mark important phases (CRCX/BTS,
etc...). Some lines lack the prefix.

Add missing prefixes.

Change-Id: Iea5ea9e54f4b5c998b1d5fe18a98a94abd7b728b
2017-12-01 13:36:30 +01:00
Philipp Maier 7eeb84271d cosmetic: do not cast void pointer
remove the casting of void *data, just assign directly

Change-Id: I2e37630e315b3602da2f14e2364bb76be9dd2894
2017-12-01 13:36:30 +01:00
Philipp Maier 06c3f8d3cb mgcp: do not fail silently on snprintf()
The snprintf() that is used to compose the fsm name on an assignment
request may cause a silent failure. The buffer is large enough to
take the string under all circumstances. If snprintf() fails, this
would mean we have some other serious problem.

use OSMO_ASSERT in case the snprintf() fails, so the failure
gets noticed.

Change-Id: I3c36df8cfd0880c524244048a993cd136be41f56
2017-12-01 13:36:30 +01:00
Philipp Maier 3ada5397d7 mgcp: add missing switch case
In the beginning of the CRCX phase for the network does not distinguish
between EV_MDCX_BTS_RES and EV_TEARDOWN, so a Teardown due to an error
could be misinterpreted as a successful MGW response.

Add missing case statement to distinguish CV_MDCX_BTS_RES from
EV_TEARDOWN.

Change-Id: I9bf49df167d94b33ad65d8b9382a01f160b5aec0
2017-12-01 13:36:30 +01:00
Philipp Maier fa85d18807 mgcp: use mgw assigned connection identifiers
osmo-mgw assigns connection identifiers which are returned with
the response to the CRCX.

store the assigned connection identifiers and use them to identify
the connections.

Depends: osmo-mgw Iab6a6038e7610c62f34e642cd49c93d11151252c

Closes: OS#2648
Change-Id: Ib379a6f40875bb8f2cf29038a5b5b7a40a21adab
2017-12-01 13:36:30 +01:00
Philipp Maier 2c3bf45449 mgcp: use hexadecimal digits in endpoint names
The current implementation of osmo-mgw parses the numerical
digit inside the endpoint name as hexadecimal number.

also use hexadecimal numbers in endpoint names.

Change-Id: I64a970d300b7290d50ec84b0640d5a321d903f5e
2017-12-01 13:36:30 +01:00
Philipp Maier 4aa2bac0bc mgcp: remove unused variable
The function handle_error asserts mgcp_ctx->conn to be non null,
but it does not access it otherwise.

remove unused variable conn

Change-Id: I09851c957395d1ddb2f9471b99ffc091bc250404
2017-11-12 14:22:46 +00:00
Philipp Maier 2a4c077fca mgcp: add missing out state
Even in the very early ST_CRCX_BTS phase, the error handler may
decide to go to ST_CALL in order to initate the termination of
a possibly half open connection.

Add ST_CALL to the out state list in ST_CRCX_BTS

Change-Id: Ic67aa7c67a4e98a38bff156be3ebf612012eb842
2017-11-12 14:22:46 +00:00
Philipp Maier 7cbea54544 cosmetic: replace term MGCP-GW with MGW
The term MGCP-GW is deprecated, use now MGW

Change-Id: Ibccda7e95c42267ce5f44e9fc4256a0083b6f68f
2017-11-12 14:22:46 +00:00
Philipp Maier 9b7678d65c cosmetic: reorder case list
the switch statement in fsm_send_assignment_complete() has the
default case at the beginning.

Move the default case to the end to match common coding style
rules

Change-Id: I360842fe899b95972c44da3cb74a3dc51b379fdc
2017-11-12 14:22:46 +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