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+ <title>Petter Reinholdtsen: Easier recipe to observe the cell phones around you</title>
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+ <div class="title">
+ <h1>
+ <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
+
+ </h1>
+
+</div>
+
+
+ <div class="entry">
+ <div class="title">Easier recipe to observe the cell phones around you</div>
+ <div class="date">24th September 2017</div>
+ <div class="body"><p>A little more than a month ago I wrote
+<a href="http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html">how
+to observe the SIM card ID (aka IMSI number) of mobile phones talking
+to nearby mobile phone base stations using Debian GNU/Linux and a
+cheap USB software defined radio</a>, and thus being able to pinpoint
+the location of people and equipment (like cars and trains) with an
+accuracy of a few kilometer. Since then we have worked to make the
+procedure even simpler, and it is now possible to do this without any
+manual frequency tuning and without building your own packages.</p>
+
+<p>The <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a>
+package is now included in Debian testing and unstable, and the
+IMSI-catcher code no longer require root access to fetch and decode
+the GSM data collected using gr-gsm.</p>
+
+<p>Here is an updated recipe, using packages built by Debian and a git
+clone of two python scripts:</p>
+
+<ol>
+
+<li>Start with a Debian machine running the Buster version (aka
+ testing).</li>
+
+<li>Run '<tt>apt install gr-gsm python-numpy python-scipy
+ python-scapy</tt>' as root to install required packages.</li>
+
+<li>Fetch the code decoding GSM packages using '<tt>git clone
+ github.com/Oros42/IMSI-catcher.git</tt>'.</li>
+
+<li>Insert USB software defined radio supported by GNU Radio.</li>
+
+<li>Enter the IMSI-catcher directory and run '<tt>python
+ scan-and-livemon</tt>' to locate the frequency of nearby base
+ stations and start listening for GSM packages on one of them.</li>
+
+<li>Enter the IMSI-catcher directory and run '<tt>python
+ simple_IMSI-catcher.py</tt>' to display the collected information.</li>
+
+</ol>
+
+<p>Note, due to a bug somewhere the scan-and-livemon program (actually
+<a href="https://github.com/ptrkrysik/gr-gsm/issues/336">its underlying
+program grgsm_scanner</a>) do not work with the HackRF radio. It do
+work with RTL 8232 and other similar USB radio receivers you can get
+very cheaply
+(<a href="https://www.ebay.com/sch/items/?_nkw=rtl+2832">for example
+from ebay</a>), so for now the solution is to scan using the RTL radio
+and only use HackRF for fetching GSM data.</p>
+
+<p>As far as I can tell, a cell phone only show up on one of the
+frequencies at the time, so if you are going to track and count every
+cell phone around you, you need to listen to all the frequencies used.
+To listen to several frequencies, use the --numrecv argument to
+scan-and-livemon to use several receivers. Further, I am not sure if
+phones using 3G or 4G will show as talking GSM to base stations, so
+this approach might not see all phones around you. I typically see
+0-400 IMSI numbers an hour when looking around where I live.</p>
+
+<p>I've tried to run the scanner on a
+<a href="https://wiki.debian.org/RaspberryPi">Raspberry Pi 2 and 3
+running Debian Buster</a>, but the grgsm_livemon_headless process seem
+to be too CPU intensive to keep up. When GNU Radio print 'O' to
+stdout, I am told there it is caused by a buffer overflow between the
+radio and GNU Radio, caused by the program being unable to read the
+GSM data fast enough. If you see a stream of 'O's from the terminal
+where you started scan-and-livemon, you need a give the process more
+CPU power. Perhaps someone are able to optimize the code to a point
+where it become possible to set up RPi3 based GSM sniffers? I tried
+using Raspbian instead of Debian, but there seem to be something wrong
+with GNU Radio on raspbian, causing glibc to abort().</p>
+</div>
+
+ <div class="tags">Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.</div>
+
+
+ </div>
+
+
+
+
+ <div id="sidebar">
+
+
+
+<h2>Archive</h2>
+<ul>
+
+<li>2017
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2017/09/">September (2)</a></li>
+
+</ul></li>
+
+<li>2016
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
+
+</ul></li>
+
+<li>2015
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
+
+</ul></li>
+
+<li>2014
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
+
+</ul></li>
+
+<li>2013
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
+
+</ul></li>
+
+<li>2012
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
+
+</ul></li>
+
+<li>2011
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
+
+</ul></li>
+
+<li>2010
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
+
+</ul></li>
+
+<li>2009
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
+
+</ul></li>
+
+<li>2008
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
+
+</ul></li>
+
+</ul>
+
+
+
+<h2>Tags</h2>
+<ul>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (16)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (152)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (158)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (17)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (24)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (352)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (30)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (18)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (42)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (15)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (20)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (39)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (292)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (189)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (33)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (64)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (103)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (10)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (5)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (53)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (55)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (6)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (12)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (51)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (3)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (59)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (40)</a></li>
+
+</ul>
+
+
+ </div>
+ <p style="text-align: right">
+ Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
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+
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