@Adam Any computer with the right ports can be a router, but you really would want a computer GNU/Linux installed and then you can configure the routing with ip and netfilter (the config is the same for a GNUbooted one running GNU/Linux-libre).

Optionally you can plug in a PCIe Wi-Fi card and configure wpa_supplicant and the routing.

"Open"WRT is just BusyBox/Linux with routing and netfilter pre-configured.


One company does sell routers that run LibreCMC (freed version of "Open"WRT); https://www.thinkpenguin.com/catalog/networking-gear-gnu-linux although that's just really a heavy markup on decent hardware - you can just purchase the hardware quite cheaply yourself and flash LibreCMC for much less costs.

People do sell GNUbooted computers, but not pre-configured as a router.


If you are installing something, what you are doing is installing software - firmware is impossible to install via software means, you need to physically replace the ROM or PROM chip to update firmware.