maintain routing table based on RKN registry
fetch_blacklist.sh is the script that simply fetches RKN registry from rublacklist.net. Run it at least once before trying to use the next script.
route.sh is the script that builds routing table based on list of ip addresses. It should be specified as the "route-up" openvpn parameter but also it can be executed alone (manually, by cron, etc) For the first time it should be executed from openvpn to parse nameservers and gateway from envinroment and store it for further use.
I use three routing tables: vpn, vpn0 and vpn1. I use "ip rule add/del" to switch between vpn{0,1}. Table vpn always have a default route via vpn. To use the script as is you should define them like this:
echo "1000 vpn" >> /etc/iproute2/rt_tables
echo "1001 vpn0" >> /etc/iproute2/rt_tables
echo "1002 vpn1" >> /etc/iproute2/rt_tables
fetch_blacklist.sh can work under any user that have an appropriate file permissions route.sh should be executed as root to perform ip(8) calls.