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<rss version='2.0' xmlns:lj='http://www.livejournal.org/rss/lj/1.0/' xmlns:atom="http://www.w3.org/2005/Atom">
        <channel>
                <title>Petter Reinholdtsen</title>
                <description></description>
                <link>http://people.skolelinux.org/pere/blog/</link>
                <atom:link href="http://people.skolelinux.org/pere/blog/index.rss" rel="self" type="application/rss+xml" />
        
        <item>
                <title>Running TP-Link MR3040 as a batman-adv mesh node using openwrt</title>
                <link>http://people.skolelinux.org/pere/blog/Running_TP_Link_MR3040_as_a_batman_adv_mesh_node_using_openwrt.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Running_TP_Link_MR3040_as_a_batman_adv_mesh_node_using_openwrt.html</guid>
                <pubDate>Sun, 10 Nov 2013 23:00:00 +0100</pubDate>
                <description>&lt;p&gt;Continuing my research into mesh networking, I was recommended to
use TP-Link 3040 and 3600 access points as mesh nodes, and the pair I
bought arrived on Friday.  Here are my notes on how to set up the
MR3040 as a mesh node using
&lt;a href=&quot;http://www.openwrt.org/&quot;&gt;OpenWrt&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;I started by following the instructions on the OpenWRT wiki for
&lt;a href=&quot;http://wiki.openwrt.org/toh/tp-link/tl-mr3040&quot;&gt;TL-MR3040&lt;/a&gt;,
and downloaded
&lt;a href=&quot;http://downloads.openwrt.org/snapshots/trunk/ar71xx/openwrt-ar71xx-generic-tl-mr3040-v2-squashfs-factory.bin&quot;&gt;the
recommended firmware image&lt;/a&gt;
(openwrt-ar71xx-generic-tl-mr3040-v2-squashfs-factory.bin) and
uploaded it into the original web interface.  The flashing went fine,
and the machine was available via telnet on the ethernet port.  After
logging in and setting the root password, ssh was available and I
could start to set it up as a batman-adv mesh node.&lt;/p&gt;

&lt;p&gt;I started off by reading the instructions from
&lt;a href=&quot;http://wirelessafrica.meraka.org.za/wiki/index.php?title=Antoine&#39;s_Research&quot;&gt;Wireless
Africa&lt;/a&gt;, which had quite a lot of useful information, but
eventually I followed the recipe from the Open Mesh wiki for
&lt;a href=&quot;http://www.open-mesh.org/projects/batman-adv/wiki/Batman-adv-openwrt-config&quot;&gt;using
batman-adv on OpenWrt&lt;/a&gt;.  A small snag was the fact that the
&lt;tt&gt;opkg install kmod-batman-adv&lt;/tt&gt; command did not work as it
should.  The batman-adv kernel module would fail to load because its
dependency crc16 was not already loaded.  I
&lt;a href=&quot;https://dev.openwrt.org/ticket/14452&quot;&gt;reported the bug&lt;/a&gt; to
the openwrt project and hope it will be fixed soon.  But the problem
only seem to affect initial testing of batman-adv, as configuration
seem to work when booting from scratch.&lt;/p&gt;

&lt;p&gt;The setup is done using files in /etc/config/.  I did not bridge
the Ethernet and mesh interfaces this time, to be able to hook up the
box on my local network and log into it for configuration updates.
The following files were changed and look like this after modifying
them:&lt;/p&gt;

&lt;p&gt;&lt;tt&gt;/etc/config/network&lt;/tt&gt;&lt;/p&gt;

&lt;pre&gt;

config interface &#39;loopback&#39;
        option ifname &#39;lo&#39;
        option proto &#39;static&#39;
        option ipaddr &#39;127.0.0.1&#39;
        option netmask &#39;255.0.0.0&#39;

config globals &#39;globals&#39;
        option ula_prefix &#39;fdbf:4c12:3fed::/48&#39;

config interface &#39;lan&#39;
        option ifname &#39;eth0&#39;
        option type &#39;bridge&#39;
        option proto &#39;dhcp&#39;
        option ipaddr &#39;192.168.1.1&#39;
        option netmask &#39;255.255.255.0&#39;
        option hostname &#39;tl-mr3040&#39;
        option ip6assign &#39;60&#39;

config interface &#39;mesh&#39;
        option ifname &#39;adhoc0&#39;
        option mtu &#39;1528&#39;
        option proto &#39;batadv&#39;
        option mesh &#39;bat0&#39;
&lt;/pre&gt;

&lt;p&gt;&lt;tt&gt;/etc/config/wireless&lt;/tt&gt;&lt;/p&gt;
&lt;pre&gt;

config wifi-device &#39;radio0&#39;
        option type &#39;mac80211&#39;
        option channel &#39;11&#39;
        option hwmode &#39;11ng&#39;
        option path &#39;platform/ar933x_wmac&#39;
        option htmode &#39;HT20&#39;
        list ht_capab &#39;SHORT-GI-20&#39;
        list ht_capab &#39;SHORT-GI-40&#39;
        list ht_capab &#39;RX-STBC1&#39;
        list ht_capab &#39;DSSS_CCK-40&#39;
        option disabled &#39;0&#39;

config wifi-iface &#39;wmesh&#39;
        option device &#39;radio0&#39;
        option ifname &#39;adhoc0&#39;
        option network &#39;mesh&#39;
        option encryption &#39;none&#39;
        option mode &#39;adhoc&#39;
        option bssid &#39;02:BA:00:00:00:01&#39;
        option ssid &#39;meshfx@hackeriet&#39;
&lt;/pre&gt;
&lt;p&gt;&lt;tt&gt;/etc/config/batman-adv&lt;/tt&gt;&lt;/p&gt;
&lt;pre&gt;

config &#39;mesh&#39; &#39;bat0&#39;
        option interfaces &#39;adhoc0&#39;
        option &#39;aggregated_ogms&#39;
        option &#39;ap_isolation&#39;
        option &#39;bonding&#39;
        option &#39;fragmentation&#39;
        option &#39;gw_bandwidth&#39;
        option &#39;gw_mode&#39;
        option &#39;gw_sel_class&#39;
        option &#39;log_level&#39;
        option &#39;orig_interval&#39;
        option &#39;vis_mode&#39;
        option &#39;bridge_loop_avoidance&#39;
        option &#39;distributed_arp_table&#39;
        option &#39;network_coding&#39;
        option &#39;hop_penalty&#39;

# yet another batX instance
# config &#39;mesh&#39; &#39;bat5&#39;
#       option &#39;interfaces&#39; &#39;second_mesh&#39;
&lt;/pre&gt;

&lt;p&gt;The mesh node is now operational.  I have yet to test its range,
but I hope it is good.  I have not yet tested the TP-Link 3600 box
still wrapped up in plastic.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Debian init.d boot script example for rsyslog</title>
                <link>http://people.skolelinux.org/pere/blog/Debian_init_d_boot_script_example_for_rsyslog.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Debian_init_d_boot_script_example_for_rsyslog.html</guid>
                <pubDate>Sat, 2 Nov 2013 22:40:00 +0100</pubDate>
                <description>&lt;p&gt;If one of the points of switching to a new init system in Debian is
&lt;a href=&quot;http://thomas.goirand.fr/blog/?p=147&quot;&gt;to get rid of huge
init.d scripts&lt;/a&gt;, I doubt we need to switch away from sysvinit and
init.d scripts at all.  Here is an example init.d script, ie a rewrite
of /etc/init.d/rsyslog:&lt;/p&gt;

&lt;p&gt;&lt;pre&gt;
#!/lib/init/init-d-script
### BEGIN INIT INFO
# Provides:          rsyslog
# Required-Start:    $remote_fs $time
# Required-Stop:     umountnfs $time
# X-Stop-After:      sendsigs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: enhanced syslogd
# Description:       Rsyslog is an enhanced multi-threaded syslogd.
#                    It is quite compatible to stock sysklogd and can be 
#                    used as a drop-in replacement.
### END INIT INFO
DESC=&quot;enhanced syslogd&quot;
DAEMON=/usr/sbin/rsyslogd
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;Pretty minimalistic to me... For the record, the original sysv-rc
script was 137 lines, and the above is just 15 lines, most of it meta
info/comments.&lt;/p&gt;

&lt;p&gt;How to do this, you ask?  Well, one create a new script
/lib/init/init-d-script looking something like this:

&lt;p&gt;&lt;pre&gt;
#!/bin/sh

# Define LSB log_* functions.
# Depend on lsb-base (&gt;= 3.2-14) to ensure that this file is present
# and status_of_proc is working.
. /lib/lsb/init-functions

#
# Function that starts the daemon/service

#
do_start()
{
        # Return
        #   0 if daemon has been started
        #   1 if daemon was already running
        #   2 if daemon could not be started
        start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test &gt; /dev/null \
                || return 1
        start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
                $DAEMON_ARGS \
                || return 2
        # Add code here, if necessary, that waits for the process to be ready
        # to handle requests from services started subsequently which depend
        # on this one.  As a last resort, sleep for some time.
}

#
# Function that stops the daemon/service
#
do_stop()
{
        # Return
        #   0 if daemon has been stopped
        #   1 if daemon was already stopped
        #   2 if daemon could not be stopped
        #   other if a failure occurred
        start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME
        RETVAL=&quot;$?&quot;
        [ &quot;$RETVAL&quot; = 2 ] &amp;&amp; return 2
        # Wait for children to finish too if this is a daemon that forks
        # and if the daemon is only ever run from this initscript.
        # If the above conditions are not satisfied then add some other code
        # that waits for the process to drop all resources that could be
        # needed by services started subsequently.  A last resort is to
        # sleep for some time.
        start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON
        [ &quot;$?&quot; = 2 ] &amp;&amp; return 2
        # Many daemons don&#39;t delete their pidfiles when they exit.
        rm -f $PIDFILE
        return &quot;$RETVAL&quot;
}

#
# Function that sends a SIGHUP to the daemon/service
#
do_reload() {
        #
        # If the daemon can reload its configuration without
        # restarting (for example, when it is sent a SIGHUP),
        # then implement that here.
        #
        start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --name $NAME
        return 0
}

SCRIPTNAME=$1
scriptbasename=&quot;$(basename $1)&quot;
echo &quot;SN: $scriptbasename&quot;
if [ &quot;$scriptbasename&quot; != &quot;init-d-library&quot; ] ; then
    script=&quot;$1&quot;
    shift
    . $script
else
    exit 0
fi

NAME=$(basename $DAEMON)
PIDFILE=/var/run/$NAME.pid

# Exit if the package is not installed
#[ -x &quot;$DAEMON&quot; ] || exit 0

# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] &amp;&amp; . /etc/default/$NAME

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

case &quot;$1&quot; in
  start)
        [ &quot;$VERBOSE&quot; != no ] &amp;&amp; log_daemon_msg &quot;Starting $DESC&quot; &quot;$NAME&quot;
        do_start
        case &quot;$?&quot; in
                0|1) [ &quot;$VERBOSE&quot; != no ] &amp;&amp; log_end_msg 0 ;;
                2) [ &quot;$VERBOSE&quot; != no ] &amp;&amp; log_end_msg 1 ;;
        esac
        ;;
  stop)
        [ &quot;$VERBOSE&quot; != no ] &amp;&amp; log_daemon_msg &quot;Stopping $DESC&quot; &quot;$NAME&quot;
        do_stop
        case &quot;$?&quot; in
                0|1) [ &quot;$VERBOSE&quot; != no ] &amp;&amp; log_end_msg 0 ;;
                2) [ &quot;$VERBOSE&quot; != no ] &amp;&amp; log_end_msg 1 ;;
        esac
        ;;
  status)
        status_of_proc &quot;$DAEMON&quot; &quot;$NAME&quot; &amp;&amp; exit 0 || exit $?
        ;;
  #reload|force-reload)
        #
        # If do_reload() is not implemented then leave this commented out
        # and leave &#39;force-reload&#39; as an alias for &#39;restart&#39;.
        #
        #log_daemon_msg &quot;Reloading $DESC&quot; &quot;$NAME&quot;
        #do_reload
        #log_end_msg $?
        #;;
  restart|force-reload)
        #
        # If the &quot;reload&quot; option is implemented then remove the
        # &#39;force-reload&#39; alias
        #
        log_daemon_msg &quot;Restarting $DESC&quot; &quot;$NAME&quot;
        do_stop
        case &quot;$?&quot; in
          0|1)
                do_start
                case &quot;$?&quot; in
                        0) log_end_msg 0 ;;
                        1) log_end_msg 1 ;; # Old process is still running
                        *) log_end_msg 1 ;; # Failed to start
                esac
                ;;
          *)
                # Failed to stop
                log_end_msg 1
                ;;
        esac
        ;;
  *)
        echo &quot;Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}&quot; &gt;&amp;2
        exit 3
        ;;
esac

:
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;It is based on /etc/init.d/skeleton, and could be improved quite a
lot.  I did not really polish the approach, so it might not always
work out of the box, but you get the idea.  I did not try very hard to
optimize it nor make it more robust either.&lt;/p&gt;

&lt;p&gt;A better argument for switching init system in Debian than reducing
the size of init scripts (which is a good thing to do anyway), is to
get boot system that is able to handle the kernel events sensibly and
robustly, and do not depend on the boot to run sequentially.  The boot
and the kernel have not behaved sequentially in years.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Browser plugin for SPICE (spice-xpi) uploaded to Debian</title>
                <link>http://people.skolelinux.org/pere/blog/Browser_plugin_for_SPICE__spice_xpi__uploaded_to_Debian.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Browser_plugin_for_SPICE__spice_xpi__uploaded_to_Debian.html</guid>
                <pubDate>Fri, 1 Nov 2013 11:00:00 +0100</pubDate>
                <description>&lt;p&gt;&lt;a href=&quot;http://www.spice-space.org/&quot;&gt;The SPICE protocol&lt;/a&gt; for
remote display access is the preferred solution with oVirt and RedHat
Enterprise Virtualization, and I was sad to discover the other day
that the browser plugin needed to use these systems seamlessly was
missing in Debian.  The &lt;a href=&quot;http://bugs.debian.org/668284&quot;&gt;request
for a package&lt;/a&gt; was from 2012-04-10 with no progress since
2013-04-01, so I decided to wrap up a package based on the great work
from Cajus Pollmeier and put it in a collab-maint maintained git
repository to get a package I could use.  I would very much like
others to help me maintain the package (or just take over, I do not
mind), but as no-one had volunteered so far, I just uploaded it to
NEW.  I hope it will be available in Debian in a few days.&lt;/p&gt;

&lt;p&gt;The source is now available from
&lt;a href=&quot;http://anonscm.debian.org/gitweb/?p=collab-maint/spice-xpi.git;a=summary&quot;&gt;http://anonscm.debian.org/gitweb/?p=collab-maint/spice-xpi.git;a=summary&lt;/a&gt;.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Teaching vmdebootstrap to create Raspberry Pi SD card images</title>
                <link>http://people.skolelinux.org/pere/blog/Teaching_vmdebootstrap_to_create_Raspberry_Pi_SD_card_images.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Teaching_vmdebootstrap_to_create_Raspberry_Pi_SD_card_images.html</guid>
                <pubDate>Sun, 27 Oct 2013 17:00:00 +0100</pubDate>
                <description>&lt;p&gt;The
&lt;a href=&quot;http://packages.qa.debian.org/v/vmdebootstrap.html&quot;&gt;vmdebootstrap&lt;/a&gt;
program is a a very nice system to create virtual machine images.  It
create a image file, add a partition table, mount it and run
debootstrap in the mounted directory to create a Debian system on a
stick.  Yesterday, I decided to try to teach it how to make images for
&lt;a href=&quot;https://wiki.debian.org/RaspberryPi&quot;&gt;Raspberry Pi&lt;/a&gt;, as part
of a plan to simplify the build system for
&lt;a href=&quot;https://wiki.debian.org/FreedomBox&quot;&gt;the FreedomBox
project&lt;/a&gt;.  The FreedomBox project already uses vmdebootstrap for
the virtualbox images, but its current build system made multistrap
based system for Dreamplug images, and it is lacking support for
Raspberry Pi.&lt;/p&gt;

&lt;p&gt;Armed with the knowledge on how to build &quot;foreign&quot; (aka non-native
architecture) chroots for Raspberry Pi, I dived into the vmdebootstrap
code and adjusted it to be able to build armel images on my amd64
Debian laptop.  I ended up giving vmdebootstrap five new options,
allowing me to replicate the image creation process I use to make
&lt;a href=&quot;http://people.skolelinux.org/pere/blog/A_Raspberry_Pi_based_batman_adv_Mesh_network_node.html&quot;&gt;Debian
Jessie based mesh node images for the Raspberry Pi&lt;/a&gt;.  First, the
&lt;tt&gt;--foreign /path/to/binfm_handler&lt;/tt&gt; option tell vmdebootstrap to
call debootstrap with --foreign and to copy the handler into the
generated chroot before running the second stage.  This allow
vmdebootstrap to create armel images on an amd64 host.  Next I added
two new options &lt;tt&gt;--bootsize size&lt;/tt&gt; and &lt;tt&gt;--boottype
fstype&lt;/tt&gt; to teach it to create a separate /boot/ partition with the
given file system type, allowing me to create an image with a vfat
partition for the /boot/ stuff.  I also added a &lt;tt&gt;--variant
variant&lt;/tt&gt; option to allow me to create smaller images without the
Debian base system packages installed.  Finally, I added an option
&lt;tt&gt;--no-extlinux&lt;/tt&gt; to tell vmdebootstrap to not install extlinux
as a boot loader.  It is not needed on the Raspberry Pi and probably
most other non-x86 architectures.  The changes were accepted by the
upstream author of vmdebootstrap yesterday and today, and is now
available from
&lt;a href=&quot;http://git.liw.fi/cgi-bin/cgit/cgit.cgi/vmdebootstrap/&quot;&gt;the
upstream project page&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;To use it to build a Raspberry Pi image using Debian Jessie, first
create a small script (the customize script) to add the non-free
binary blob needed to boot the Raspberry Pi and the APT source
list:&lt;/p&gt;

&lt;p&gt;&lt;pre&gt;
#!/bin/sh
set -e # Exit on first error
rootdir=&quot;$1&quot;
cd &quot;$rootdir&quot;
cat &amp;lt;&amp;lt;EOF &gt; etc/apt/sources.list
deb http://http.debian.net/debian/ jessie main contrib non-free
EOF
# Install non-free binary blob needed to boot Raspberry Pi.  This
# install a kernel somewhere too.
wget https://raw.github.com/Hexxeh/rpi-update/master/rpi-update \
    -O $rootdir/usr/bin/rpi-update
chmod a+x $rootdir/usr/bin/rpi-update
mkdir -p $rootdir/lib/modules
touch $rootdir/boot/start.elf
chroot $rootdir rpi-update
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;Next, fetch the latest vmdebootstrap script and call it like this
to build the image:&lt;/p&gt;

&lt;pre&gt;
sudo ./vmdebootstrap \
    --variant minbase \
    --arch armel \
    --distribution jessie \
    --mirror http://http.debian.net/debian \
    --image test.img \
    --size 600M \
    --bootsize 64M \
    --boottype vfat \
    --log-level debug \
    --verbose \
    --no-kernel \
    --no-extlinux \
    --root-password raspberry \
    --hostname raspberrypi \
    --foreign /usr/bin/qemu-arm-static \
    --customize `pwd`/customize \
    --package netbase \
    --package git-core \
    --package binutils \
    --package ca-certificates \
    --package wget \
    --package kmod
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;The list of packages being installed are the ones needed by
rpi-update to make the image bootable on the Raspberry Pi, with the
exception of netbase, which is needed by debootstrap to find
/etc/hosts with the minbase variant.  I really wish there was a way to
set up an Raspberry Pi using only packages in the Debian archive, but
that is not possible as far as I know, because it boots from the GPU
using a non-free binary blob.&lt;/p&gt;

&lt;p&gt;The build host need debootstrap, kpartx and qemu-user-static and
probably a few others installed.  I have not checked the complete
build dependency list.&lt;/p&gt;

&lt;p&gt;The resulting image will not use the hardware floating point unit
on the Raspberry PI, because the armel architecture in Debian is not
optimized for that use.  So the images created will be a bit slower
than &lt;a href=&quot;http://www.raspbian.org/&quot;&gt;Raspbian&lt;/a&gt; based images.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Det er jo makta som er mest sårbar ved massiv overvåkning av Internett</title>
                <link>http://people.skolelinux.org/pere/blog/Det_er_jo_makta_som_er_mest_s_rbar_ved_massiv_overv_kning_av_Internett.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Det_er_jo_makta_som_er_mest_s_rbar_ved_massiv_overv_kning_av_Internett.html</guid>
                <pubDate>Sat, 26 Oct 2013 20:30:00 +0200</pubDate>
                <description>&lt;p&gt;De siste måneders eksponering av
&lt;a href=&quot;http://www.aftenposten.no/nyheter/uriks/Her-er-Edvard-Snowdens-mest-omtalte-avsloringer-7351734.html&quot;&gt;den
totale overvåkningen som foregår i den vestlige verden dokumenterer
hvor sårbare vi er&lt;/a&gt;.  Men det slår meg at de som er mest sårbare
for dette, myndighetspersoner på alle nivåer, neppe har innsett at de
selv er de mest interessante personene å lage profiler på, for å kunne
påvirke dem.&lt;/p&gt;

&lt;p&gt;For å ta et lite eksempel: Stortingets nettsted,
&lt;a href=&quot;http://www.stortinget.no/&quot;&gt;www.stortinget.no&lt;/a&gt; (og
forsåvidt også
&lt;a href=&quot;http://data.stortinget.no/&quot;&gt;data.stortinget.no&lt;/a&gt;),
inneholder informasjon om det som foregår på Stortinget, og jeg antar
de største brukerne av informasjonen der er representanter og
rådgivere på Stortinget.  Intet overraskende med det.  Det som derimot
er mer skjult er at Stortingets nettsted bruker
&lt;a href=&quot;http://en.wikipedia.org/wiki/Google_Analytics&quot;&gt;Google
Analytics&lt;/a&gt;, hvilket gjør at enhver som besøker nettsidene der også
rapporterer om besøket via Internett-linjer som passerer Sverige,
England og videre til USA.  Det betyr at informasjon om ethvert besøk
på stortingets nettsider kan snappes opp av svensk, britisk og USAs
etterretningsvesen.  De kan dermed holde et øye med hvilke
Stortingssaker stortingsrepresentantene synes er interessante å sjekke
ut, og hvilke sider rådgivere og andre på stortinget synes er
interessant å besøke, når de gjør det og hvilke andre representanter
som sjekker de samme sidene omtrent samtidig.  Stortingets bruk av
Google Analytics gjør det dermed enkelt for utenlands etteretning å
spore representantenes aktivitet og interesse.  Hvis noen av
representantene bruker Google Mail eller noen andre tjenestene som
krever innlogging, så vil det være enda enklere å finne ut nøyaktig
hvilke personer som bruker hvilke nettlesere og dermed knytte
informasjonen opp til enkeltpersoner på Stortinget.&lt;/p&gt;

&lt;p&gt;Og jo flere nettsteder som bruker Google Analytics, jo bedre
oversikt over stortingsrepresentantenes lesevaner og interesse blir
tilgjengelig for svensk, britisk og USAs etterretning.  Hva de kan
bruke den informasjonen til overlater jeg til leseren å undres
over.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>A Raspberry Pi based batman-adv Mesh network node</title>
                <link>http://people.skolelinux.org/pere/blog/A_Raspberry_Pi_based_batman_adv_Mesh_network_node.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/A_Raspberry_Pi_based_batman_adv_Mesh_network_node.html</guid>
                <pubDate>Mon, 21 Oct 2013 11:40:00 +0200</pubDate>
                <description>&lt;p&gt;The last few days I have been experimenting with
&lt;a href=&quot;http://www.open-mesh.org/projects/batman-adv/wiki&quot;&gt;the
batman-adv mesh technology&lt;/a&gt;.  I want to gain some experience to see
if it will fit &lt;a href=&quot;https://wiki.debian.org/FreedomBox&quot;&gt;the
Freedombox project&lt;/a&gt;, and together with my neighbors try to build a
mesh network around the park where I live.  Batman-adv is a layer 2
mesh system (&quot;ethernet&quot; in other words), where the mesh network appear
as if all the mesh clients are connected to the same switch.&lt;/p&gt;

&lt;p&gt;My hardware of choice was the Linksys WRT54GL routers I had lying
around, but I&#39;ve been unable to get them working with batman-adv.  So
instead, I started playing with a
&lt;a href=&quot;http://www.raspberrypi.org/&quot;&gt;Raspberry Pi&lt;/a&gt;, and tried to
get it working as a mesh node.  My idea is to use it to create a mesh
node which function as a switch port, where everything connected to
the Raspberry Pi ethernet plug is connected (bridged) to the mesh
network.  This allow me to hook a wifi base station like the Linksys
WRT54GL to the mesh by plugging it into a Raspberry Pi, and allow
non-mesh clients to hook up to the mesh.  This in turn is useful for
Android phones using &lt;a href=&quot;http://servalproject.org/&quot;&gt;the Serval
Project&lt;/a&gt; voip client, allowing every one around the playground to
phone and message each other for free.  The reason is that Android
phones do not see ad-hoc wifi networks (they are filtered away from
the GUI view), and can not join the mesh without being rooted.  But if
they are connected using a normal wifi base station, they can talk to
every client on the local network.&lt;/p&gt;

&lt;p&gt;To get this working, I&#39;ve created a debian package
&lt;a href=&quot;https://github.com/petterreinholdtsen/meshfx-node&quot;&gt;meshfx-node&lt;/a&gt;
and a script
&lt;a href=&quot;https://github.com/petterreinholdtsen/meshfx-node/blob/master/build-rpi-mesh-node&quot;&gt;build-rpi-mesh-node&lt;/a&gt;
to create the Raspberry Pi boot image.  I&#39;m using Debian Jessie (and
not Raspbian), to get more control over the packages available.
Unfortunately a huge binary blob need to be inserted into the boot
image to get it booting, but I&#39;ll ignore that for now.  Also, as
Debian lack support for the CPU features available in the Raspberry
Pi, the system do not use the hardware floating point unit.  I hope
the routing performance isn&#39;t affected by the lack of hardware FPU
support.&lt;/p&gt;

&lt;p&gt;To create an image, run the following with a sudo enabled user
after inserting the target SD card into the build machine:&lt;/p&gt;

&lt;p&gt;&lt;pre&gt;
% wget -O build-rpi-mesh-node \
    https://raw.github.com/petterreinholdtsen/meshfx-node/master/build-rpi-mesh-node
% sudo bash -x ./build-rpi-mesh-node &gt; build.log 2&gt;&amp;1
% dd if=/root/rpi/rpi_basic_jessie_$(date +%Y%m%d).img of=/dev/mmcblk0 bs=1M
%
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;Booting with the resulting SD card on a Raspberry PI with a USB
wifi card inserted should give you a mesh node.  At least it does for
me with a the wifi card I am using. The default mesh settings are the
ones used by the Oslo mesh project at Hackeriet, as I mentioned in
&lt;a href=&quot;http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html&quot;&gt;an
earlier blog post about this mesh testing&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;The mesh node was not horribly expensive either.  I bought
everything over the counter in shops nearby.  If I had ordered online
from the lowest bidder, the price should be significantly lower:&lt;/p&gt;

&lt;p&gt;&lt;table&gt;

&lt;tr&gt;&lt;th&gt;Supplier&lt;/th&gt;&lt;th&gt;Model&lt;/th&gt;&lt;th&gt;NOK&lt;/th&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;Teknikkmagasinet&lt;/td&gt;&lt;td&gt;Raspberry Pi model B&lt;/td&gt;&lt;td&gt;349.90&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;Teknikkmagasinet&lt;/td&gt;&lt;td&gt;Raspberry Pi type B case&lt;/td&gt;&lt;td&gt;99.90&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;Lefdal&lt;/td&gt;&lt;td&gt;Jensen Air:Link 25150&lt;/td&gt;&lt;td&gt;295.-&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;Clas Ohlson&lt;/td&gt;&lt;td&gt;Kingston 16 GB SD card&lt;/td&gt;&lt;td&gt;199.-&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;Total cost&lt;/td&gt;&lt;td&gt;&lt;/td&gt;&lt;td&gt;943.80&lt;/td&gt;&lt;/tr&gt;

&lt;/table&gt;&lt;/p&gt;

&lt;p&gt;Now my mesh network at home consist of one laptop in the basement
connected to my production network, one Raspberry Pi node on the 1th
floor that can be seen by my neighbor across the park, and one
play-node I use to develop the image building script.  And some times
I hook up my work horse laptop to the mesh to test it.  I look forward
to figuring out what kind of latency the batman-adv setup will give,
and how much packet loss we will experience around the park. :)&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Perl library to control the Spykee robot moved to github</title>
                <link>http://people.skolelinux.org/pere/blog/Perl_library_to_control_the_Spykee_robot_moved_to_github.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Perl_library_to_control_the_Spykee_robot_moved_to_github.html</guid>
                <pubDate>Sat, 19 Oct 2013 10:20:00 +0200</pubDate>
                <description>&lt;p&gt;Back in 2010, I created a Perl library to talk to
&lt;a href=&quot;http://en.wikipedia.org/wiki/Spykee&quot;&gt;the Spykee robot&lt;/a&gt;
(with two belts, wifi, USB and Linux) and made it available from my
web page.  Today I concluded that it should move to a site that is
easier to use to cooperate with others, and moved it to github.  If
you got a Spykee robot, you might want to check out
&lt;a href=&quot;https://github.com/petterreinholdtsen/libspykee-perl&quot;&gt;the
libspykee-perl github repository&lt;/a&gt;.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Good causes: Debian Outreach Program for Women, EFF documenting the spying and Open access in Norway</title>
                <link>http://people.skolelinux.org/pere/blog/Good_causes__Debian_Outreach_Program_for_Women__EFF_documenting_the_spying_and_Open_access_in_Norway.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Good_causes__Debian_Outreach_Program_for_Women__EFF_documenting_the_spying_and_Open_access_in_Norway.html</guid>
                <pubDate>Tue, 15 Oct 2013 21:30:00 +0200</pubDate>
                <description>&lt;p&gt;The last few days I came across a few good causes that should get
wider attention.  I recommend signing and donating to each one of
these. :)&lt;/p&gt;

&lt;p&gt;Via &lt;a href=&quot;http://www.debian.org/News/weekly/2013/18/&quot;&gt;Debian
Project News for 2013-10-14&lt;/a&gt; I came across the Outreach Program for
Women program which is a Google Summer of Code like initiative to get
more women involved in free software.  One debian sponsor has offered
to match &lt;a href=&quot;http://debian.ch/opw2013&quot;&gt;any donation done to Debian
earmarked&lt;/a&gt; for this initiative.  I donated a few minutes ago, and
hope you will to. :)&lt;/p&gt;

&lt;p&gt;And the Electronic Frontier Foundation just announced plans to
create &lt;a href=&quot;https://supporters.eff.org/donate/nsa-videos&quot;&gt;video
documentaries about the excessive spying&lt;/a&gt; on every Internet user that
take place these days, and their need to fund the work.  I&#39;ve already
donated.  Are you next?&lt;/p&gt;

&lt;p&gt;For my Norwegian audience, the organisation Studentenes og
Akademikernes Internasjonale Hjelpefond is collecting signatures for a
statement under the heading
&lt;a href=&quot;http://saih.no/Bloggers_United/&quot;&gt;Bloggers United for Open
Access&lt;/a&gt; for those of us asking for more focus on open access in the
Norwegian government.  So far 499 signatures.  I hope you will sign it
too.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Oslo community mesh network - with NUUG and Hackeriet at Hausmania</title>
                <link>http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html</guid>
                <pubDate>Fri, 11 Oct 2013 14:10:00 +0200</pubDate>
                <description>&lt;p&gt;Wireless mesh networks are self organising and self healing
networks that can be used to connect computers across small and large
areas, depending on the radio technology used.  Normal wifi equipment
can be used to create home made radio networks, and there are several
successful examples like
&lt;a href=&quot;http://www.freifunk.net/&quot;&gt;Freifunk&lt;/a&gt; and
&lt;a href=&quot;http://www.awmn.net/&quot;&gt;Athens Wireless Metropolitan Network&lt;/a&gt;
(see
&lt;a href=&quot;http://en.wikipedia.org/wiki/List_of_wireless_community_networks_by_region#Greece&quot;&gt;wikipedia
for a large list&lt;/a&gt;) around the globe.  To give you an idea how it
work, check out the nice overview of the Kiel Freifunk community which
can be seen from their
&lt;a href=&quot;http://freifunk.in-kiel.de/ffmap/nodes.html&quot;&gt;dynamically
updated node graph and map&lt;/a&gt;, where one can see how the mesh nodes
automatically handle routing and recover from nodes disappearing.
There is also a small community mesh network group in Oslo, Norway,
and that is the main topic of this blog post.&lt;/p&gt;

&lt;p&gt;I&#39;ve wanted to check out mesh networks for a while now, and hoped
to do it as part of my involvement with the &lt;a
href=&quot;http://www.nuug.no/&quot;&gt;NUUG member organisation&lt;/a&gt; community, and
my recent involvement in
&lt;a href=&quot;https://wiki.debian.org/FreedomBox&quot;&gt;the Freedombox project&lt;/a&gt;
finally lead me to give mesh networks some priority, as I suspect a
Freedombox should use mesh networks to connect neighbours and family
when possible, given that most communication between people are
between those nearby (as shown for example by research on Facebook
communication patterns).  It also allow people to communicate without
any central hub to tap into for those that want to listen in on the
private communication of citizens, which have become more and more
important over the years.&lt;/p&gt;

&lt;p&gt;So far I have only been able to find one group of people in Oslo
working on community mesh networks, over at the hack space
&lt;a href=&quot;http://hackeriet.no/&quot;&gt;Hackeriet&lt;/a&gt; at Husmania.  They seem to
have started with some Freifunk based effort using OLSR, called
&lt;a href=&quot;http://oslo.freifunk.net/index.php?title=Main_Page&quot;&gt;the Oslo
Freifunk project&lt;/a&gt;, but that effort is now dead and the people
behind it have moved on to a batman-adv based system called
&lt;a href=&quot;http://meshfx.org/trac&quot;&gt;meshfx&lt;/a&gt;.  Unfortunately the wiki
site for the Oslo Freifunk project is no longer possible to update to
reflect this fact, so the old project page can&#39;t be updated to point to
the new project.  A while back, the people at Hackeriet invited people
from the Freifunk community to Oslo to talk about mesh networks.  I
came across this video where Hans Jørgen Lysglimt interview the
speakers about this talk (from
&lt;a href=&quot;https://www.youtube.com/watch?v=N2Kd7CLkhSY&quot;&gt;youtube&lt;/a&gt;):&lt;/p&gt;

&lt;p&gt;&lt;iframe width=&quot;420&quot; height=&quot;315&quot; src=&quot;https://www.youtube.com/embed/N2Kd7CLkhSY&quot; frameborder=&quot;0&quot; allowfullscreen&gt;&lt;/iframe&gt;&lt;/p&gt;

&lt;p&gt;I mentioned OLSR and batman-adv, which are mesh routing protocols.
There are heaps of different protocols, and I am still struggling to
figure out which one would be &quot;best&quot; for some definitions of best, but
given that the community mesh group in Oslo is so small, I believe it
is best to hook up with the existing one instead of trying to create a
completely different setup, and thus I have decided to focus on
batman-adv for now.  It sure help me to  know that the very cool
&lt;a href=&quot;http://www.servalproject.org/&quot;&gt;Serval project in Australia&lt;/a&gt;
is using batman-adv as their meshing technology when it create a self
organizing and self healing telephony system for disaster areas and
less industrialized communities.  Check out this cool video presenting
that project (from
&lt;a href=&quot;https://www.youtube.com/watch?v=30qNfzJCQOA&quot;&gt;youtube&lt;/a&gt;):&lt;/p&gt;

&lt;p&gt;&lt;iframe width=&quot;560&quot; height=&quot;315&quot; src=&quot;https://www.youtube.com/embed/30qNfzJCQOA&quot; frameborder=&quot;0&quot; allowfullscreen&gt;&lt;/iframe&gt;&lt;/p&gt;

&lt;p&gt;According to the wikipedia page on
&lt;a href=&quot;http://en.wikipedia.org/wiki/Wireless_mesh_network&quot;&gt;Wireless
mesh network&lt;/a&gt; there are around 70 competing schemes for routing
packets across mesh networks, and OLSR, B.A.T.M.A.N. and
B.A.T.M.A.N. advanced are protocols used by several free software
based community mesh networks.&lt;/p&gt;

&lt;p&gt;The batman-adv protocol is a bit special, as it provide layer 2
(as in ethernet ) routing, allowing ipv4 and ipv6 to work on the same
network.  One way to think about it is that it provide a mesh based
vlan you can bridge to or handle like any other vlan connected to your
computer.  The required drivers are already in the Linux kernel at
least since Debian Wheezy, and it is fairly easy to set up.  A
&lt;a href=&quot;http://www.open-mesh.org/projects/batman-adv/wiki/Quick-start-guide&quot;&gt;good
introduction&lt;/a&gt; is available from the Open Mesh project.  These are
the key settings needed to join the Oslo meshfx network:&lt;/p&gt;

&lt;p&gt;&lt;table&gt;
&lt;tr&gt;&lt;th&gt;Setting&lt;/th&gt;&lt;th&gt;Value&lt;/th&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;Protocol / kernel module&lt;/td&gt;&lt;td&gt;batman-adv&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;ESSID&lt;/td&gt;&lt;td&gt;meshfx@hackeriet&lt;/td&gt;&lt;/tr&gt;
&lt;td&gt;Channel / Frequency&lt;/td&gt;&lt;td&gt;11 / 2462&lt;/td&gt;&lt;/tr&gt;
&lt;td&gt;Cell ID&lt;/td&gt;&lt;td&gt;02:BA:00:00:00:01&lt;/td&gt;
&lt;/table&gt;&lt;/p&gt;

&lt;p&gt;The reason for setting ad-hoc wifi Cell ID is to work around bugs
in firmware used in wifi card and wifi drivers.  (See a nice post from
VillageTelco about
&quot;&lt;a href=&quot;http://tiebing.blogspot.no/2009/12/ad-hoc-cell-splitting-re-post-original.html&quot;&gt;Information
about cell-id splitting, stuck beacons, and failed IBSS merges!&lt;/a&gt;
for details.)  When these settings are activated and you have some
other mesh node nearby, your computer will be connected to the mesh
network and can communicate with any mesh node that is connected to
any of the nodes in your network of nodes. :)&lt;/p&gt;

&lt;p&gt;My initial plan was to reuse my old Linksys WRT54GL as a mesh node,
but that seem to be very hard, as I have not been able to locate a
firmware supporting batman-adv.  If anyone know how to use that old
wifi access point with batman-adv these days, please let me know.&lt;/p&gt;

&lt;p&gt;If you find this project interesting and want to join, please join
us on IRC, either channel
&lt;a href=&quot;irc://irc.freenode.net/#oslohackerspace&quot;&gt;#oslohackerspace&lt;/a&gt;
or &lt;a href=&quot;irc://irc.freenode.net/#nuug&quot;&gt;#nuug&lt;/a&gt; on
irc.freenode.net.&lt;/p&gt;

&lt;p&gt;While investigating mesh networks in Oslo, I came across an old
research paper from the university of Stavanger and Telenor Research
and Innovation called
&lt;a href=&quot;http://folk.uio.no/paalee/publications/netrel-egeland-iswcs-2008.pdf&quot;&gt;The
reliability of wireless backhaul mesh networks&lt;/a&gt; and elsewhere
learned that Telenor have been experimenting with mesh networks at
Grünerløkka in Oslo.  So mesh networks are also interesting for
commercial companies, even though Telenor discovered that it was hard
to figure out a good business plan for mesh networking and as far as I
know have closed down the experiment.  Perhaps Telenor or others would
be interested in a cooperation?&lt;/p&gt;

&lt;p&gt;&lt;strong&gt;Update 2013-10-12&lt;/strong&gt;: I was just
&lt;a href=&quot;http://lists.alioth.debian.org/pipermail/freedombox-discuss/2013-October/005900.html&quot;&gt;told
by the Serval project developers&lt;/a&gt; that they no longer use
batman-adv (but are compatible with it), but their own crypto based
mesh system.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Skolelinux / Debian Edu 7.1 install and overview video from Marcelo Salvador</title>
                <link>http://people.skolelinux.org/pere/blog/Skolelinux___Debian_Edu_7_1_install_and_overview_video_from_Marcelo_Salvador.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Skolelinux___Debian_Edu_7_1_install_and_overview_video_from_Marcelo_Salvador.html</guid>
                <pubDate>Tue, 8 Oct 2013 17:10:00 +0200</pubDate>
                <description>&lt;p&gt;The other day I was pleased and surprised to discover that Marcelo
Salvador had published a
&lt;a href=&quot;https://www.youtube.com/watch?v=w-GgpdqgLFc&quot;&gt;video on
Youtube&lt;/a&gt; showing how to install the standalone Debian Edu /
Skolelinux profile.  This is the profile intended for use at home or
on laptops that should not be integrated into the provided network
services (no central home directory, no Kerberos / LDAP directory etc,
in other word a single user machine).  The result is 11 minutes long,
and show some user applications (seem to be rather randomly picked).
Missed a few of my favorites like celestia, planets and chromium
showing the &lt;a href=&quot;http://www.zygotebody.com/&quot;&gt;Zygote Body 3D model
of the human body&lt;/a&gt;, but I guess he did not know about those or find
other programs more interesting. :) And the video do not show the
advantages I believe is one of the most valuable featuers in Debian
Edu, its central school server making it possible to run hundreds of
computers without hard drives by installing one central
&lt;a href=&quot;http://www.ltsp.org/&quot;&gt;LTSP server&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;Anyway, check out the video, embedded below and linked to above:&lt;/p&gt;

&lt;iframe width=&quot;420&quot; height=&quot;315&quot; src=&quot;http://www.youtube.com/embed/w-GgpdqgLFc&quot; frameborder=&quot;0&quot; allowfullscreen&gt;&lt;/iframe&gt;

&lt;p&gt;Are there other nice videos demonstrating Skolelinux?  Please let
me know. :)&lt;/p&gt;
</description>
        </item>
        
        </channel>
</rss>