In efforts to customize a D-Link DIR-615 with dd-wrt and enable an ipv6 stack protocol for global ipv6 address resolution device I had to first hack the D-Link and flash with the dd-wrt binary image. Next, I have to modify the firmware image with various packages and alter the linux configuration to enable ipv6 functionality.
There are tools to extract and modify the firmware image here:
dd-wrt and openwrt have cross compatible packages that can be added in and taken away from the linux image. A compressed file system is used in the image given that flash space for the root file system is very limited.
Following other instructions from others who are working on enabling this functionality in routers and learning how to hack arm linux devices. Obviously these basic skills will lead to other possibilities to employ custom wifi routers for other applications, or other arm based linux devices