0 Starting access point hangs!
Matias Barcenas edited this page 2017-12-10 07:03:03 -06:00

About This Issue

The access point service hangs when a problem occurs with the wireless interface preventing the start of the AP service chosen. Before checking if your wireless device supports master mode with the linux drivers, try disabling any network managers that might be interfering with the networking interface you're trying to use. Beware, the following commands will disconnect your device from any networks it's currently connected to (temporarily):

# The following is the network manager for Kali, and other Debian derivatives.
# After you're done with fluxion, start the service by replacing stop with start.
systemctl stop network-manager.service

# The following is the network manager for used for Raspbian, and similar platforms.
# After you're done with fluxion, start the service by replacing stop with start.
systemctl stop wpa_supplicant.service

Try running fluxion after disabling the network manager for your system.

If you continue to have the same issue after following the instructions above, you must verify your wireless device supports both, master mode, and virtual interfaces.

** Notice, fluxion supports using two wireless devices simultaneously.** This means you can avoid virtual interfaces by using a secondary wireless interface. If you take this route, make sure the interface you select for the scanner supports injection, and the second interface you choose (once you launch the Captive Portal attack) supports master mode.

Verifying Master Mode

To verify your driver supports master mode with hostpad, try the following.
Pick an interface you'd like to use and switch it to monitor mode:

airmon-ng start wlanX

Alternatively, try:

ip link set wlanX down
iwconfig wlanX mode monitor
ip link set wlanX up

Alternatively, try:

ifconfig wlanX down
iwconfig wlanX mode monitor
ifconfig wlanX up

Check the interface is in monitor mode by looking for "Mode:Monitor" after running:

iwconfig wlanX

Now, create a test configuration file with the following content:

interface=wlanX
driver=nl80211
ssid=TestAP
channel=1

Save it as hostapd.conf, then try starting hostapd with it:

hostapd hostapd.conf

You should get the following output on your terminal:

Configuration file: hostapd.conf
Using interface wlanX with hwaddr XX:XX:XX:XX:XX:XX and ssid "TestAP"
wlanX: interface state UNINITIALIZED->ENABLED
wlanX: AP-ENABLED

If this looks fine, check with another device (like a phone/tablet) if a new AP is available.
The AP will not have any routes. That means any attempts to connect to it will fail. However, it should spawn and you should see it available on the other device.

If all the steps succeeded and you're able to see a new wireless network, your driver supports master mode with hostapd.
To kill hostapd, simply do ctrl+c.

Verify Virtual Interface Functionality

Fluxion requires virtual networking interfaces when utilizing a single interface. This is due to the fact some attacks, such as the Captive Portal attack, require two different wireless actions to succeed, such as Captive Portal requiring a jammer for the target AP and an access point for the rogue AP.

The objective here is to utilize a single physical device with two virtual interfaces. For this we need to create a secondary interface from our main interface. First we need to select an interface we would like to work with and "reserve it" by setting it into monitor mode:

ip link set wlanX down # Deactivate interface
iwconfig wlanX mode monitor # Switch interface to monitor mode (revert by switching to "managed" mode)
ip link set wlanX up # Activate interface

The command(s) in the block above should not generate any type of output, if any output is shown chances are something went wrong.

Next, we need to add the secondary virtual interface from the primary interface:

iw dev wlanX interface add wlanY type monitor

The command(s) in the block above should not generate any type of output, if any output is shown chances are something went wrong.

Both interfaces should be ready at this point, so now we'll attempt to use them simultaneously.

The primary interface, wlanX, will run the jammer, while the secondary interface, wlanY, will run the rogue AP. Make sure you're running the jammer legally, follow your local laws and don't be an asshole. For this part, you'll need the channel set in the configuration file for hostapd created above. Create a file with the target's MAC address, not the rogue network's MAC address:

XX:XX:XX:XX:XX:XX

Save it as target.lst in your desktop.

Modify the hostapd configuration file created in the hostapd section to update the interface

interface=wlanY
driver=nl80211
ssid=TestAP
channel=1

Save it on your desktop as hostapd.conf.

Start the mdk3 deauthenticator on the primary interface:

mdk3 wlanX d -c TARGET_CHANNEL_HERE -b ~/Desktop/target.lst

This will start mdk3 in deauthentication test mode.

On another terminal, start hostapd on the secondary interface:

hostapd ~/Desktop/hostapd.conf

If everything succeeded, you should see mdk3 and hostapd running and working without stopping. If everything succeeded, fluxion should work fine.