Commit Graph

22 Commits

Author SHA1 Message Date
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 cbdfb78f7b HO: move penalty timers to own file as proper API
Separate penalty timers API from specific struct members and move to own .h/.c
file, so that future code may re-use the API arbitrarily.

Change-Id: Ife975a1c7c17a500b1693be620475a8bea72f86f
2018-02-16 16:11:16 +01:00
Neels Hofmeyr cbc999cb93 HO: logging: more logs, and more concise logging
Explicitly log "Handover" or "Assignment", add more info to existing log
statements and add more log statements.

Log ho failure both on RR and HO log categories: RR receives the HO failure
message, while the HO failure is an important event to note when watching the
HO category.

Change-Id: Ia3999755cdd4e0c2861582b20e2dbb7e1538e074
2018-02-16 16:11:16 +01:00
Harald Welte b794887cab remove obsolete gsm_subscriber_connection.bts member
This member was merely a cache for conn->lchan->ts->trx->bts,
so let's avoid having to keep copies of the same data (which needs
to be kept up to date).

Change-Id: Id3bff8b18425ef5d45eb460ac9eb620023013ba0
2018-01-28 03:23:00 +01:00
Andreas Eversberg 084b421fba HO: Add a penalty timer list to the subscriber connection entity
This penalty timer is used to temporarily block cells where handover
or assignment failed or where handover is not allowed. This is usefull
to prevent repeated handover attempts to broken cells or cells that have
limited allowed distance.

Change-Id: I95cb7e3211b2470b773965e7aa94d8eb6c8c1a3a
2018-01-22 01:57:50 +00:00
Andreas Eversberg 935e5d76dd HO: add queue to cache DTAP messages during handover/assignment
Add ho_dtap_cache to gsm_subscriber_connection, a stock msgb queue to be used
with msgb_enqueue() and msgb_dequeue().

Keep a counter of queue length, to enforce a sane maximum counter for cached
messages. So far a hardcoded maximum of 23 messages will be cached.

Have balanced ho_dtap_cache_add() and ho_dtap_cache_flush() functions.

The original patch was by jolly, but I have basically completely replaced it
with the simpler msgb queue pattern.

Change-Id: I6e4d93628befb3d97e5cee0343cd9f8ba0b8620c
2018-01-19 22:09:19 +00:00
Andreas Eversberg 5d45c0732a Allow assignment to TCH channel with signalling only mode
This makes sense, if silent call is used. Assignment allows to change from
SDCCH (or whatever was available) to given TCH rate.

Change-Id: I2efe9d7ab429e902581ebb9e0e006f2aec6d8972
2018-01-19 16:03:16 +01:00
Andreas Eversberg 3106c16b4f Do not perform assignment, if the new channel equals the current one
This can happen, if a TCH/H was requested, but because it is not available,
a TCH/F is allocated. If the old channel was TCH/F already, it makes no
sense to assign it.

Change-Id: I284125483fc14b8f82e32ee61aa3866746238eae
2018-01-19 16:03:16 +01:00
Andreas Eversberg e0cba56dad HO: If handover logic is used to do assignment, signal assignment result
Change-Id: I465caef03626e67d9b3a21bdf730589b9852c211
2018-01-19 16:03:16 +01:00
Andreas Eversberg 4d3baa6bdf Fix of checking TCH rate at chan_compat_with_mode
In case of current channel equals TCH/F and we request half rate, we
must return 0, so the calling function will trigger assignment.

Change-Id: Ibb4cb9aef1a1146f984d7c969bfba53c647cae07
2018-01-19 16:03:16 +01:00
Harald Welte 148ee361b3 cosmetic: Hide all accesses to conn->bts behind conn_get_bts()
This is a new inline function that hides all accesses to conn->bts.

A follow-up patch will then point this to conn->lchan->ts->trx->bts
to get rid of the bts field.

Change-Id: Ib6cf7097ced34eebe80441c29ab1534f21956a33
2017-12-23 00:23:08 +01:00
Harald Welte 472275c301 remove unused 'lac' member of 'struct gsm_subscriber_connection'
This field was used in write-pnly mode, i.e. set but never read.

Change-Id: I319945538fd3e3bc5cf3b9d82533641cb8ba5256
2017-12-19 18:58:51 +01:00
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
Neels Hofmeyr 8c6301cf0d debug log: log Cipher Mode info upon sending down RSL/A-bis
Change-Id: I7f7ec44887f6b40fdce8d348e9e9bd200fe0b689
2017-12-14 21:39:49 +01:00
Neels Hofmeyr 64c2920620 log typo fix in gsm0808_cipher_mode()
Change-Id: I3f6d138df9ddc9c6560d04e2e8baa1f3a50a164f
2017-12-14 21:39:44 +01:00
Pau Espin 73ab3f070a bsc_api: Fix NULL secondary_lchan access in handle_ass_fail
Related: OW#3893

Program terminated with signal SIGSEGV, Segmentation fault.
0  gsm_lchan_name (lchan=lchan@entry=0x0) at gsm_data_shared.c:342
(gdb) bt
0  gsm_lchan_name (lchan=lchan@entry=0x0) at gsm_data_shared.c:342
1  0x0805ab80 in lchan_release (lchan=0x0, sacch_deact=sacch_deact@entry=0, mode=mode@entry=RSL_REL_LOCAL_END)
    at chan_alloc.c:410
2  0x0805c1dd in handle_ass_fail (msg=0x94142b8, conn=0x9251048) at bsc_api.c:459
3  dispatch_dtap (msg=0x94142b8, link_id=0 '\000', conn=0x9251048) at bsc_api.c:598
4  gsm0408_rcvmsg (msg=msg@entry=0x94142b8, link_id=0 '\000') at bsc_api.c:658
5  0x08058ca2 in abis_rsl_rx_rll (msg=0x94142b8) at abis_rsl.c:1686
6  abis_rsl_rcvmsg (msg=0x94142b8) at abis_rsl.c:2097
7  0xb7e8cf9a in handle_ts1_read (bfd=0x94e8e08) at input/ipaccess.c:271
8  ipaccess_fd_cb (bfd=0x94e8e08, what=1) at input/ipaccess.c:386
9  0xb7ee8434 in osmo_select_main (polling=polling@entry=0) at select.c:158
10 0x0804bd7c in main (argc=6, argv=0xbfc27144) at osmo_bsc_main.c:272
(gdb) print lchan
$2 = (const struct gsm_lchan *) 0x0

Possible scenario in which this crash can appear:
1- gsm0808_assign_req() calls handle_new_assignment() which sends an CHAN
ACTIVATE msg and arms T10 timer.
2- ACTIVATE ACK is received (handle_chan_ack), which calls
gsm48_send_rr_ass_cmd() which sends an ASSIGNMENT CMD, and doesn't
disable/modify T10 timer.
3- T10 timeout is triggered (assignment_t10_timeout()), which sets
conn->secondary_lchan = NULL
4- Immediately after, the ASSIGNMENT FAILURE message (which might have been
already queued) is processed in handle_ass_fail, and then the crash occurs.

This race condition is not an issue for handle_ass_compl() path because there's
this check there which would trigger most probably if secondary_lchan is NULL:
"if (conn->secondary_lchan != msg->lchan)"

Change-Id: I3798b36c628f75d4e8bc7b0996c27d695d53fbb1
2017-10-17 10:10:44 +02:00
Neels Hofmeyr c01647914b move include/openbsc to include/osmocom/bsc
Change-Id: I39e7b882caa98334636d19ccd104fd83d07d5055
2017-09-06 16:26:13 +02:00
Neels Hofmeyr 7b656884cf split off osmo-bsc: remove files, apply build
Change-Id: I64d84c52f6e38e98144eb9be8f0ab82e0e1f6cca
2017-08-30 14:11:25 +02:00
Harald Welte 2f97f42d5b bsc_api: Fix copy+paste error in printing name of RR STATUS PDU
Change-Id: I0ef78ef046e4850346569f750693e12938b50ab5
2017-08-27 03:52:45 +02:00
Neels Hofmeyr ce4d88bd62 mscsplit: various preparations to separate MSC from BSC
Disable large parts of the code that depend on BSC presence. The code sections
disabled by #if BEFORE_MSCSPLIT shall be modified or dropped in the course of
adding the A-interface.

Don't set msg->lchan nor msg->dst.
Don't use lchan in libmsc.
Decouple lac from bts.

Prepare entry/exit point for MSC -> BSC and MSC -> RNC communication:
Add msc_ifaces.[hc], a_iface.c, with a general msc_tx_dtap() to redirect to
different interfaces depending on the actual subscriber connection.
While iu_tx() is going to be functional fairly soon, the a_tx() is going to be
just a dummy for some time (see comment).
Add Iu specific fields in gsm_subscriber_connection: the UE connection pointer
and an indicator for the Integrity Protection status on Iu (to be fully
implemented in later commits).
Add lac member to gsm_subscriber_connection, to allow decoupling from
bts->location_area_code. The conn->lac will actually be set in iu.c in an
upcoming commit ("add iucs.[hc]").

move to libcommon-cs: gsm48_extract_mi(), gsm48_paging_extract_mi().

libmsc: duplicate gsm0808 / gsm48 functions (towards BSC).
In osmo-nitb, libmsc would directly call the functions on the BSC level, not
always via the bsc_api. When separating libmsc from libbsc, some functions are
missing from the linkage.
Hence duplicate these functions to libmsc, add an msc_ prefix for clarity, also
add a _tx to gsm0808_cipher_mode():
* add msc_gsm0808_tx_cipher_mode() (dummy/stub)
* add msc_gsm48_tx_mm_serv_ack()
* add msc_gsm48_tx_mm_serv_rej()
Call these from libmsc instead of
* gsm0808_cipher_mode()
* gsm48_tx_mm_serv_ack()
* gsm48_tx_mm_serv_rej()
Also add a comment related to msc_gsm0808_tx_cipher_mode() in two places.

Remove internal RTP streaming code; OsmoNITB supported that, but for OsmoMSC,
this will be done with an external MGCP gateway.

Remove LCHAN_MODIFY from internal MNCC state machine.

Temporarily disable all paging to be able to link libmsc without libbsc.
Skip the paging part of channel_test because the paging is now disabled.
Employ fake paging shims in order for msc_vlr_tests to still work.

msc_compl_l3(): publish in .h, tweak return value.  Use new libmsc enum values
for return val, to avoid dependency on libbsc headers.  Make callable from
other scopes: publish in osmo_msc.h and remove 'static' in osmo_msc.c

add gsm_encr to subscr_conn
move subscr_request to gsm_subscriber.h
subscr_request_channel() -> subscr_request_conn()
move to libmsc: osmo_stats_vty_add_cmds()
gsm_04_08: remove apply_codec_restrictions()
gsm0408_test: use NULL for root ctx
move to libbsc: gsm_bts_neighbor()
move to libbsc: lchan_next_meas_rep()
move vty config for t3212 to network level (periodic lu)
remove unneccessary linking from some tests
remove handle_abisip_signal()
abis_rsl.c: don't use libvlr from libbsc

gsm_subscriber_connection: put the LAC here, so that it is available without
accessing conn->bts. In bsc_api.c, place this lac in conn for the sake of
transition: Iu and A will use this new field to pass the LAC around, but in a
completely separate OsmoBSC this is not actually needed. It can be removed
again from osmo-bsc.git when the time has come.

Siemens MRPCI: completely drop sending the MRPCI messages for now, they shall
be added in osmo-bsc once the A-Interface code has settled. See OS#2389.

Related: OS#1845 OS#2257 OS#2389
Change-Id: Id3705236350d5f69e447046b0a764bbabc3d493c
2017-08-27 03:52:44 +02:00
Harald Welte a43e0b4d9a Use libvlr in libmsc (large refactoring)
Original libvlr code is by Harald Welte <laforge@gnumonks.org>,
polished and tweaked by Neels Hofmeyr <nhofmeyr@sysmocom.de>.

This is a long series of trial-and-error development collapsed in one patch.
This may be split in smaller commits if reviewers prefer that. If we can keep
it as one, we have saved ourselves the additional separation work.

SMS:

The SQL based lookup of SMS for attached subscribers no longer works since the
SQL database no longer has the subscriber data. Replace with a round-robin on
the SMS recipient MSISDNs paired with a VLR subscriber RAM lookup whether the
subscriber is currently attached.

If there are many SMS for not-attached subscribers in the SMS database, this
will become inefficient: a DB hit returns a pending SMS, the RAM lookup will
reveal that the subscriber is not attached, after which the DB is hit for the
next SMS. It would become more efficient e.g. by having an MSISDN based hash
list for the VLR subscribers and by marking non-attached SMS recipients in the
SMS database so that they can be excluded with the SQL query already.

There is a sanity limit to do at most 100 db hits per attempt to find a pending
SMS. So if there are more than 100 stored SMS waiting for their recipients to
actually attach to the MSC, it may take more than one SMS queue trigger to
deliver SMS for subscribers that are actually attached.

This is not very beautiful, but is merely intended to carry us over to a time
when we have a proper separate SMSC entity.

Introduce gsm_subscriber_connection ref-counting in libmsc.

Remove/Disable VTY and CTRL commands to create subscribers, which is now a task
of the OsmoHLR. Adjust the python tests accordingly.

Remove VTY cmd subscriber-keep-in-ram.

Use OSMO_GSUP_PORT = 4222 instead of 2222. See
I4222e21686c823985be8ff1f16b1182be8ad6175.

So far use the LAC from conn->bts, will be replaced by conn->lac in
Id3705236350d5f69e447046b0a764bbabc3d493c.

Related: OS#1592 OS#1974
Change-Id: I639544a6cdda77a3aafc4e3446a55393f60e4050
2017-08-27 03:52:44 +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