Connecting a computer without WLAN to a WLAN access point
Wireless network clients don't have bridging capabilities, because the network adapter cannot change it's MAC-address. However, it is possible to »bridge« a single computer over Wireless, by not using the wireless adapter locally and forwarding all the packet to a destination computer.
WLAN_Kabel implements this use case. It allows to connect a computer without any Wireless adapters to a Wireless LAN using a »proxy« device, such as a netbook, equipped with both Ethernet and Wireless.
WLAN_Kabel will only work for one single network device. It will not work with multiple devices, not even with virtualized ones.
If you want to bridge multiple devices, you'll have to use 4addr mode on the WLAN device instead of WLAN_Kabel. However, in practise this is often not an option, because almost every AP will completely ignore any 4addr packets per default for security reasons. WLAN_Kabel, on the other hand, will work with every AP out of the box.
You can compile WLAN_Kabel by just entering make. You will probably need make, a C-compiler and kernel headers installed.
To use WLAN_Kabel, you have to install it on the proxy device. Both the Wireless and the Ethernet adapter must be up, but not configured for any IP addresses. You can then start as root it like this:
# ./wlan_kabel <wlan-adapter> <ethernet-adapter> <MAC of device to connect>
Example:
# ./wlan_kabel wlan0 eth0 00:22:15:49:e5:55
You can then connect your computer to the proxy device with a patch cable and bring it up normally - it will work with DHCP, etc.
WLAN_Kabel has been tested on:
- ATH9K chipset with Ubuntu 10.10
- Ralink RT2870 on a Raspberry Pi
You may use this code under the conditions of the GNU GPL v2 or later.