Hi Domi,
Thanks! While I building the same, I was wondering 'may be SAP protocol' was built for it. But thanks again for confirming it! And Yes, I used an external card reader too. I did not check all osmocom projects, just checked out softSIM it does mention SAP. Sounds great! Thanks for the feedback again.
Thanks, Gerard
On Tue, Mar 28, 2017 at 12:27 AM, Tomcsányi, Domonkos domi@tomcsanyi.net wrote:
Hi Gerard
- márc. 28. dátummal, 9:10 időpontban Gerard Pinto <
gerardfly9@gmail.com> írta:
- I have been trying something different with OsmocomBB, osmo-sim-auth
and Tor lately - I would like to hear your views on the same.
Attack Model: Geo-Location Anonymous calling in GSM.
Description:
- The attacker uses OsmocomBB phone to make a call using a sim card
service. (No sim card present in the phone).
- For this, I have taken the SIM card outside OsmocomBB and re-written
all SIM API's in osmo-sim-auth (which is the sim card service).
- This sim card service is deployed over Tor network, so no one can
actually know the location of the SIM card service.
4, The osmocombb connects to the network and uses this sim card service
for authentication etc.
- The whole setup of calling etc is initiated by the sim card service,
which is itself behind Tor.
- Now, This SIM card service can be used my multiple phones, so now you
are not exactly going to track the phone since if I use the SIM card service to another phone (cell area) the DB entry in VLR has changed which says the location has changed.
- My experiments worked well on a LIVE network, understanding the delay
in Tor the network, still, the BTS was accepting RES response challenge from the SIM card service behind Tor - I still have to calculate the exact max acceptable delay in sending RES back to BTS to confirm this!
This is a very interesting idea, I like it! I wanted to mention the SAP protocol that is available in OsmocomBB's mobile app via a Unix domain socket since some time now. It might be even easier to use it for your idea. I used it via an external card reader and softSIM to provide a SIM card for OsmocomBB.
Cheers,
Domi