I'm looking to develop a custom firmware similiar to DD-WRT, Tomato, or other popular custom router firmwares.
I was thinking it would be best if it were based off OpenWRT, but am open to alternative suggestions. I'm looking for it to supported under the most commonly available hardware (WRT54G, etc).
On the WAN side It will need to support several VPN clients (PPTP, L2TP/IPSec and OpenVPN) as well as a passthrough mode (for direct connectivity via WAN with out dialing a VPN) for connectivity. The WAN port will need to first obtain an IP address via DHCP before connecting to a VPN, or appling passthrough mode as per settings. Will need to have a custom web interface to allow the user to configure LAN, WAN, and common NAT/security settings. Router will need to contact our servers to obtain an XML list of vpn server locations, addresses, and relevant settings for easy configuration.