OpenBSC November 2018

openbsc@lists.osmocom.org

23 participants
34 discussions

Splitting out M3UA and MTP3 out of Open BSC into a separate library
by Arran Cudbard-Bell 19 Nov '25

19 Nov '25

Hi, Developing a module for FreeRADIUS to support EAP-SIM and EAP-AKA authentication against a HLR. The HLR we were targeting only supported a SCTP/M3UA/SCCP/TCAP/MAP stack, so we couldn't use SUA. Ripping the M3UA/MTP3 code out of OpenBSC worked surprisingly well. We ended up running the event loop in a separate thread to work around the threading issues. Unfortunately the HLR implements the ANSI variant of everything, whereas OpenBSC and supporting libraries seem to have been written to be compatible with the ITU standards. ...but the differences are fairly minor at MTP3 and SCCP layers, and i've started work on a patchset for libosmo-sccp. https://gerrit.osmocom.org/#/c/73/ Anyway, trying to gauge interest in splitting those layers out of Open BSC into a separate library, would be happy to take on M2UA as well for consistency. It would almost certainly get more projects using the code. There's very little out there even in Perl land for working with SS7. Thanks, -Arran Arran Cudbard-Bell <a.cudbardb(a)freeradius.org> FreeRADIUS Development Team FD31 3077 42EC 7FCD 32FE 5EE2 56CF 27F9 30A8 CAA2

5 5

ip.access nano 3G S8 Configuration
by John Thewlis - Meath Broadband 18 Nov '25

18 Nov '25

We are trying to setup this AP as part of the 3.5G Osmocom project. We have the software stack operational and are now preparing the nano for testing. When we try to login via telnet at port 8090 we are getting a constant refusal to connect:- root@osm/openbsc/openbsc/src/ipaccess# telnet 192.168.192.30 8090 Trying 192.168.192.30... telnet: Unable to connect to remote host: Connection refused The device seems to be locked as indicated by the leds on the front panel. We have tried resetting the nano to see if this would help but to no avail. Any ideas as to how to access the device for initial configuration?. Thanks John

4 4

GPRS - local and foreign TLLIs
by Luca Melette 18 Nov '25

18 Nov '25

Hello everybody, after setting up a nanoBTS with OpenBSC/SGSN/GGSN, I had some troubles trying to connect my smartphone to the GPRS cell. Investigating the BTS-to-SGSN traffic, I saw that the frames sent by the SGSN were all marked with the same N(U) value (at LLC layer), the value was 0. With some debug, I found that the there was a mismatch in the TLLI storage, used to keep the status of attached terminals. The mentioned code is contained in gprs_llc.c, involving LL Entity functions and gprs_llc_tx_ui(). /* look-up or create the LL Entity for this (TLLI, SAPI) tuple */ lle = lle_by_tlli_sapi(msgb_tlli(msg), sapi); if (!lle) { struct gprs_llc_llme *llme; LOGP(DLLC, LOGL_ERROR, "LLC TX: unknown TLLI 0x%08x, " "creating LLME on the fly\n", msgb_tlli(msg)); llme = llme_alloc(msgb_tlli(msg)); lle = &llme->lle[sapi]; } The TX function uses the previously received TLLI to lookup for the LLE. The lle_by_tlli_sapi() performs the search, but preliminary it applies a foreign2local TLLI conversion to ensure to have a local one. Since no valid entry for the searched TLLI is found, a new one is created. And the problem is here. The new entry has the foreign TLLI. Next time the lookup fails again, and a new entry is created. This way, the counter N(U) is always reset, and the mobile do not recognize the message sequence and no attach is possible. My question is about foreign and local TLLIs. I patched the lookup, avoiding the conversion, so that the LLE is found and everything works fine... but... What is the sense of the conversion? Should the TLLI be always stored as a local one? Can this problem be solved with another foreign2local while allocating new entries? Actually, my problem has been solved with that workaround. But I'm curious to know what is the right way. Hope somebody can answer :) Thanks. Cheers, LM

4 5

Need nano3G (S8 - Model 237A)
by Akib Sayyed 18 Nov '25

18 Nov '25

Dear List I am extremely sorry for off the topic question. I am willing to buy nano3G Nodeb. Is anyone in list have spare which can be sold. Please let me know. -- Akib Sayyed Matrix-Shell akibsayyed(a)gmail.com akibsayyed(a)matrixshell.com Mob:- +91-966-514-2243 <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campai…> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campai…> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

4 3

Pysim error: SW match failed
by Martin Nagy 16 Aug '25

16 Aug '25

Hi all, After buying a super Sim Kit (16 in 1) from China, I tried the reader (green PCB inside a blue transparent plastic case with a blue LED) and SIM (identified as a fakesupersim) with pysim tool. However i am getting the following error: /pySim-prog.py -n 26C3 -c 49 -x 262 -y 42 -z 1234 -j 1 -t auto Insert card now (or CTRL-C to cancel) Autodetected card type fakemagicsim Generated card parameters : > Name : 26C3 > SMSP : e1ffffffffffffffffffffffff058100945555ffffffffffff000000 > ICCID : 8949262427518313026 > MCC/MNC : 262/42 > IMSI : 262422461512085 > Ki : 7b74741a1ee14337ec23f9ab92a13648 > OPC : ccd867d60797d8d45354a51b3ef568ff Programming ... Traceback (most recent call last): File "./pySim-prog.py", line 530, in <module> card.program(cp) File "/home/nadicek/pysim/pysim/pySim/cards.py", line 231, in program self._scc.update_binary('6f30', hplmn + 'ff' * (tl-3)) File "/home/nadicek/pysim/pysim/pySim/commands.py", line 53, in update_binary return self._tp.send_apdu_checksw(pdu) File "/home/nadicek/pysim/pysim/pySim/transport/__init__.py", line 87, in send_apdu_checksw raise RuntimeError("SW match failed ! Expected %s and got %s." % (sw.lower(), rv[1])) RuntimeError: SW match failed ! Expected 9000 and got 9804. I checked mailing lists and haven’t found anybody who had similar problem with pysim. Also I have tried forcing different models of SIM, but nothing is working. Obviously I can remove this check from the script file (__init__.py in /pySim/transport), however somebody had a reason to put such condition there. I would like to ask if it is safe to remove that line of code and the purpose of that line of code. Thanks a lot and best regards Martin

3 3

Re: Help with sccp library
by mosbah abdelkader 07 Jul '25

07 Jul '25

> I don't understand. This callback will be called with data you need to write > to the network. In case of MTP Level3 you will need to wrap that around the > msgb you got. I means: is the interaction with mtp3 layer implemented (is sending sccp data by mtp3 implemented by the library?)? Also, what about the reception of data from mtp3 layer. is that implemented in the sccp lib. I am asking these questions because I see the code of mtp3 in the lib but no significant call is present in the sccp part of the lib. Thank you for your help.

4 3

dynamic traffic channels
by Neels Hofmeyr 20 May '25

20 May '25

On Tue, Jun 28, 2016 at 10:05:28AM +0200, Harald Welte wrote: > [translated from german] > is it certain that we switch a channel to PDCH only when > gprs mode != none? A TS can be GSM_PCHAN_TCH_F_PDCH; those are the only ones for which we send a PDCH ACT message. We send a PDCH ACT message - during init (CHANNEL OML's state changed to enabled -> send PDCH ACT), - and upon channel release ack when pchan == GSM_PCHAN_TCH_F_PDCH. So the question is, when we receive a channel release ack, could that be the PDCH release and we switch PDCH right back on by accident? No, because we only receive a chan rel ack when the *TCH/F* is being released. That is because the PDCH release is initiated "internally" from the PDCH DEACT, and thus this condition in common/rsl.c rsl_tx_rf_rel_ack() catches on, which existed before dyn PDCH: if (lchan->rel_act_kind != LCHAN_REL_ACT_RSL) { LOGP(DRSL, LOGL_NOTICE, "%s not sending REL ACK\n", gsm_lchan_name(lchan)); return 0; } In rsl_rx_rf_chan_rel() the rel_act_kind is set to LCHAN_REL_ACT_RSL, but not in the rsl_rx_dyn_pdch(). This is analogous to the ip.access way -- the ip.access nanobts replies to a PDCH DEACT with a PDCH DEACT ACK and doesn't send a separate channel release ack. Maybe we could set rel_act_kind to some new LCHAN_REL_ACT_IPAC_DYN_PDCH for clarity? (But we shouldn't actually send a release ack, to stay compatible.) Even though it works as-is, we should indeed add another flag check: - We do check the flags that no ACT/DEACT is already pending; - And we do send a PDCH DEACT only if ts->flags & TS_F_PDCH_ACTIVE; - But we would send a PDCH ACT despite ts->flags & TS_F_PDCH_ACTIVE. This should never happen, but it would make sense to ensure that. ~Neels

3 5

voting in gerrit: merge at +3? (+2+1 / +1+1+1)
by Stefan Sperling 12 Dec '18

12 Dec '18

There has been some face-to-face discussion about Osmocom's code review process within sysmocom recently. I am posting to this list now with the consent of everyone involved so far, in order to involve the Osmocom community at large in this discussion as well. There has been a lack of code review from people who don't have "+2" super powers in Gerrit. This applies to anyone among us, independently of any individual's relationship with sysmocom. The bulk of the work involved in reviewing code falls on Harald's shoulders, with Pau and Neels sharing most of the rest between themselves. At present, while people who add a +1 have their voices heard, their input does not formally affect the decision to merge a change. A change still has to pass by the pre-selected +2 gatekeepers in order to be merged, no matter how many other people have provided input. The implication for developers without +2 powers is that their time is more effectively spent on advancing their own changes towards a +2 vote, rather than spending time on whatever else is waiting in Gerrit. This may not apply to everyone, of course. But at least for me, this is certainly the case; I have only been reviewing other people's patches when I was explicitly asked to do so. Myself and several other developers hope that with a change to our review process we can fix this inertia, spread code review across more shoulders and encourage more collaborative code review in Osmocom. The basic idea is that everyone's input should count for something. If those among us with +1 powers were given a partial say on the fate of every change, our decisions will carry more weight and our influence within the project will slightly increase. We'd also be encouraged to step out of our own corners of expertise every now and then, and look at what other developers are working on. On the flip side, this means we'd carry more responsibility than we do now. We wouldn't always be relying on our +2 gate keepers and would have to apply our own judgement more carefully. The concrete proposal is to make votes in Gerrit accumulative. Each change would require a total score of +3 to be merged. This score can consist of either a +2 and a +1 vote, or three +1 votes; and no -1 votes. Also, +2 developers would keep their ability to unilaterally block or revert changes under this new model. They'd keep their existing role as arbiters in case of disputes. Max figured out how Gerrit could be configured for this behaviour. It involves Prolog code, but since we're all quite smart we should be able to figure that out, right? https://gerrit-review.googlesource.com/Documentation/prolog-cookbook.html#_… We'd be interested to hear what the community thinks about this proposal. Thanks, Stefan

7 43

Info on Alcatel Femtocells
by Alex 29 Nov '18

29 Nov '18

Hi to everyone! I'm a new member and I really appreciate the work done here! I'm trying to use Alcatel Femtocells (ALU 9361/9362/9363) with osmo-hnbgw, but I'm still blocked at the IPSEC tunnel step. I've created an IPSEC server with EAP support, but I suspect there is a problem with my self signed certificate. Probably the femtocell has an internal trusted CA which validates server certs. I din't find the console pins on the board also, so I cannot simply connect to it and have a look at the system level. Has anyone any experience with this kind of HW or just an idea about a possible work around? Thank you and best regards Alex

2 6

HEADS UP: don't merge .adoc or vty ref changes to osmo-gsm-manuals.git anymore!
by Neels Hofmeyr 28 Nov '18

28 Nov '18

The adocs and vty reference content from osmo-gsm-manuals.git has been "moved" to the individual project repositories. That means if you apply more .adoc changes to osmo-gsm-manuals.git, we have to port that to the new location. (The content is not yet removed from osmo-gsm-manuals.git, so you might run into believing the move hasn't happened yet.) You can already edit in the individual osmo-bsc,-msc,... repositories, and build with 'configure --enable-manuals'. The jenkins publishing job isn't updated yet, should follow soon. right, osmith? ~N

3 4

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

OpenBSC November 2018