Wireless cards.

Wireless cards are very different based upon what chipset you have. I personally use Atheros chipset cards which has screwed me up a bit with BackTrack as it has problems with using them for certain attacks.

What I will again show is generic commands for setting up and configuring your wireless interfaces.

The interface name (ath0 below) is entirely dependant on what chipset you are using, you may have any of the following:

ath0 wlan0 wifi0 eth0 You need to find out what you have. To do this you should execute the following bash command:

iwconfig -a

This will show all wireless extension on your machine. You should see all of your network interfaces, but only the wireless ones will have detailed information next to it. Now you know what your wireless cards name is...

Switch on your wireless card:

ifconfig ath0 up

To connect to an 'open' wireless access point (AP):

iwconfig ath0 essid 'nameofnetwork'

The 'nameofnetwork' is your Service Set IDentifer (SSID). That is the name of your network.

To configure a WEP key:

iwconfig ath0 key 3B5D3C7D207E37DCEEEDD301E3

To connect to a specific AP:

iwconfig ath0 ap 03:27:A8:BC:0F:F1

Where '03:27:A8:BC:0F:F1' is the MAC address of your AP, also known as the Basic Service Set IDentifier (BSSID).

Once you have setup your connection, you can get a DHCP address:

dhcpcd ath0

Then check that you have an IP from the wireless network.

But what if the network uses WPA? Again you need to assign the essid and maybe an AP MAC, then:

Create a text based file called wpa_supplicant.conf

Enter the following:

network={ essid="nameofnetwork" key_mgmt=WPA-PSK proto=WPA pairwise=TKIP group=TKIP psk="WPApassphrase"
}

Where nameofnetwork is your essid and psk is your WPA pre-shared key!

Then run the wpa_supplicant tool.

wpa_supplicant -D madwifi -i ath0 -c wpa_supplicant.conf

This will need altering depending on what chipset and drivers you are using. The above should work for an Atheros card.

Saying all of the above about WPA configurations, I have had many problems with it on BackTrack. If someone else has other suggestions, please post here. Also, please post setup commands for other types of wireless cards.

To put your wireless card into monitor mode:

iwconfig ath0 mode monitor

To restrict it to one specific channel:

iwconfig ath0 channel XX

Make sure you use a two figure number, channel 1 tends to put you on channel 11 for some reason!

Again, they are for Atheros cards, other cards have other commands.

I hope this has helped people in understanding a little more about the configuration settings for their wireless cards. Don't forget the wlassisstant tool on BackTrack too.