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Linksys WRT54GL resurrection

Last week I was experimenting with various changes to OpenWrt Kamikaze version 7.09 on my Linksys WRT54GL wireless router. The objective was to modify the Kamikaze firmware for WRT54GL in order to implement a rogue access point for use in various penetration testing contracts. I decided to start the whole endeavor since the Airsnarf Rogue Squadron firmware only supports the WRT54G model. After a lot of successful firmware flashings during testing, I eventually (and perhaps unavoidably) flashed my router with a corrupted firmware. The result was a dead WRT54GL that was not replying to pings, not even after a hard reset.

To resurrect it I followed void main’s WRT54G revival guide. Although the guide was written for the WRT54G model, it is mostly applicable to WRT54GL as well. One of the main differences is that I had to short pins 16 and 17, not 15 and 16 (see the photograph):

A rather important tip is that right after a successful flashing you should always enable the boot_wait NVRAM option in order to be able to use the TFTP bootloader. This will save you a lot of time if you are in the “edit-compile-upload firmware-debug” loop.