The US Government policy towards permitting it’s citizens to create/modify firmware on some forms of devices has been clarified:
More info:
http://www.extremetech.com/internet/218017-fcc-removes-reference-to-dd-wrt-from-guidelines-swears-it-will-not-ban-third-party-router-firmware
http://arstechnica.com/information-technology/2015/11/fcc-we-arent-banning-dd-wrt-on-wi-fi-routers/
http://www.theregister.co.uk/2015/11/12/fcc_revises_router_update_rules/
http://hightechforum.org/fcc-clarifies-the-ask-for-wi-fi-routers/
Firmware Security 