==== Using Kismet under FreeBSD ====

Kismet sounds to be a nice tool for Wi-Fi diagnostics.
Port installation can be easily done via:

<code>
cd /usr/ports/net-mgmt/kismet && make install clean
</code>

Within newly installed ''%%/usr/local/etc/kismet.conf%%'', one
needs to enable particular packet sources, Wi-Fi channels
and a user, to which ''%%kismet(1)%%'' with ''%%setuid(2)%%'':

Depending on ''%%kismet%%'' version, there are two different packet sources formats. Users of port version older than **2010.07.r1,1** (port tree copy older than 2010-10-03)  have **Kismet-Old**, newer port version use **Kismet-Newcore**.

=== Kismet-Newcore ===

Kismet-Newcore (currently the base Kismet code) use ''%%ncsource=%%'' variable and this syntax:

<code>
ncsource=<wireless device>:type=<wireless nic type/capture format>,name=<user friendly source name>
</code>

Sample Kismet-Newcore configuration:

<code>
ncsource=wlan0:type=radiotap_bsd_g,name=ath_pci
</code>

%%FreeBSD%% supports following types (depending on hardware): radiotap_bsd_ag, radiotap_bsd_a, radiotap_bsd_g, radiotap_bsd_b.

Kismet-Newcore have setuid-root capture helper binary ''%%kismet_capture%%'' which may be executed by users in the kismet group. Add your user to kismet group before you run kismet. Option ''%%suiduser%%'' was removed from configuration file in Kismet-Newcore.

=== Kismet-Old ===

Kismet-Old release (Kismet-Old2009-05-R1) use ''%%source=%%'' variable, with different format:

<code>
source=<wireless nic type/capture format>,<wireless device>,<user friendly source name>
</code>

Sample %%FreeBSD%% configuration for Kismet-Old:

<code>
suiduser = <your user here>

[...]

source=radiotap_bsd_ab,wlan0,bsd

[...]
sourcechannels=radiotap_bsd_ab:1,6,11,2,7,3,8,4,9,5,10
</code>

In order to make kismet text-based CLI to work, one needs
to enable DBUS. It should be already installed in your system.
Enabling means inserting particular line into your ''%%/etc/rc.conf%%''
file:

<code>
dbus_enable="yes"
</code>

=== Creating monitor VAP ===

In order to start working with ''%%wlan0%%'' interface which we have mentioned
as a available packet source, we need to create it. This step is different
from creating WLAN interface in default mode -- we need to create VAP
(Virtual Access Point) interface working in "monitor mode":

<code>
ifconfig wlan create wlandev bwi0 wlanmode monitor
</code>

for Broadcom-based card, or:

<code>
ifconfig wlan create wlandev ath0 wlanmode monitor
</code>

for Atheros-based card.

This is basically the end of the setup procedure. You can start Kismet
right now.

Let me know if this short tutorial has some flaws:

[[wkoszek@FreeBSD.org|Wojciech A. Koszek]]