March 2013 - OpenBSC - lists.osmocom.org

GPRS - local and foreign TLLIs
by Luca Melette 04 Feb '26

04 Feb '26

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

5 6

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

Re: Any interest for Osmocom meetings in Bavaria ?
by Dieter Spaar 11 Jun '13

11 Jun '13

So far three persons have indicated their interest to join a meeting at my place. Considering the time it takes to drive to my place, it probably makes sense to have the meeting at the weekend (either Saturday or Sunday) so that there is more time for the meeting itself. I can suggest one of the following dates for the first meeting, somewhere between 10:00 to 18:00 on each day: 25.8. (Sa) or 26.8. (Su) 1.9. (Sa) or 2.9. (Su) 8.9. (Sa) or 9.9. (Su) So please let me know when you have time and also make suggestions in which Osmocom topic you are interested in so that we can have some sort of agenda for the meeting to make best use of the time. Best regards, Dieter -- Dieter Spaar, Germany spaar(a)mirider.augusta.de

10 40

SimpleHLR: A web interface for OpenBSC
by Peter Caprioli 03 Jun '13

03 Jun '13

Hello everyone, I've just finnished writing together a small web interface for the OpenBSC HLR. It allows you to modify various parameters in the database and also provides a set of functions to modify the HLR or sending SMSes in your own scripts. The project is still very alpha but it seems to work reasonably good. Feel free to give any feedback! Screenshots and source code is available on my website: https://stormhub.org/simplehlr/ -- *Best regards, Peter Caprioli*

3 6

Bounce action notification
by mailman＠lists.osmocom.org 31 Mar '13

31 Mar '13

This is a Mailman mailing list bounce action notice: List: OpenBSC Member: fabrice.poundeu(a)smail.inf.fh-bonn-rhein-sieg.de Action: Subscription disabled. Reason: Excessive or fatal bounces. The triggering bounce notice is attached below. Questions? Contact the Mailman site administrator at mailman(a)lists.osmocom.org.

1 0

NEWSDR'13 Workshop / OpenBSC / OsmocomBB
by Harald Welte 31 Mar '13

31 Mar '13

Hi All, as I've just been made aware of by a business contact, there is a NEWSDR'13 workshop which, among other things, has OsmocomBB and OpenBSC on the list of topics: http://ecewp.ece.wpi.edu/wordpress/sdr-boston/newsdr-13/call-for-papers/ Did anyone ever hear of this workshop? Did the organizers ever make contact with us? I'm a bit surprised that somebody organizes a workshop with "our" projects on the agenda without even sending the CfP to us. Or maybe I just missed it? In case somebody is submitting a paper there: Please make sure to coordinate here in order to avoid different developers/contributors from submitting similar/related topics. Regards, Harald -- - Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

2 1

Re: NEWSDR'13 Workshop / OpenBSC / OsmocomBB (Harald Welte)
by Robin Coxe 30 Mar '13

30 Mar '13

I've never heard of either this workshop or the SDR Boston Listserv and don't know any of the people on the organizing committee. One of the moderators of the mailing list, which I just joined, is an EE professor at Northeastern University, Miriam Lesser, who is well known in the FPGA community. Since I'm based in Boston, I'll plan to attend provided I'm not traveling for my day job. If anyone would like to participate by proxy, please let me know. [If I can get my act together in time, I may demo OpenBTS ported to a Xilinx Zynq using the new Close-Haul GAPfiller RF front end.] -Robin

1 0

Problem with flashing BS-11
by Sergey V. Efimov 27 Mar '13

27 Mar '13

Hello All, Did anyone ever experienced such strange problems when downloading firmware into BS-11? === $ bs11_config bs11_config (C) 2009-2010 by Harald Welte and Dieter Spaar This is FREE SOFTWARE with ABSOLUTELY NO WARRANTY LMT LOGON: ACK PHASE: 1 Software required Abis-link: Down <0005> abis_nm.c:1196 Software Load (BTS 0, File "BTSBMC76.SWI") Software Load Initiate ACK === ...and then nothing happens for hours. I.e., no progress percentage, segment acknowledges, etc. Does it mean that BTS is broken or something other? Regards, Sergey.

1 1

Range Networks: Open Source Cellular Networks
by Markus Zielonka 27 Mar '13

27 Mar '13

"Range Networks formally introduced today its executive management team to deliver a complete open source software version of the cellular system. Range Networks says it is the world’s leading provider of American-made commercial open source cellular systems and is slashing the cost to own and operate mobile networks." http://www.dailywireless.org/2013/03/26/range-networks-open-source-cellular…

1 0

Leak/Double-free handling in SGSN
by Holger Hans Peter Freyther 26 Mar '13

26 Mar '13

Hi, I was discussing this crash[1] with Jan at the 29C3 and recently in Iceland. On top of that Katarina pointed me to the best practises[2] of talloc. In general I disagree with them[3] but they provide a nice solution for the SGSN/MSGB ownership issue. Methods that send a msgb should create a new local context and attach it to a global context for all local contexts (so we see them in the leak report). This would probably be done with a helper function in libosmocore. Once the msgb is created, we will steal it into the local context. Then we pass it down the rabbit hole. Once it is reaching the write_queue it is stolen back (or into a write queue context). The initial caller will free his local context. And now there are three options: a.) The msgb has made it into the write_queue. b.) The msgb has been already deleted due to an error c.) The msgb is still in the local context and will be freed. Using the talloc_steal and the local context will make sure we do not leak and do not double free. We can (and should) add a warning to see under which circumstances the msgb has not been freed. I think the implementation of this will be about 10-15 lines of code (probably too optimistic). comments? holger [1] http://openbsc.osmocom.org/trac/ticket/55 [2] http://talloc.samba.org/talloc/doc/html/libtalloc__bestpractices.html [3] Most of our functions only allocate one object. There is no point in having a hierachy of ROOT -> SingleObject. This indirection is wasteful in most cases.

1 1