How to block Tor exit nodes from accessing your website

//SRC: http://mikhailian.mova.org/node/194

Internet trolls are using Tor nowadays to avoid bans by IP. However, banning Tor exit nodes is just slightly more complex. The Tor Project provides a regularly updated list of exit nodes that can access your IP here:
(https://check.torproject.org/cgi-bin/TorBulkExitList.py).

As there may be many hundreds or even thousands of nodes, adding them to iptables can hurt your server's network performance. Enter ipset(http://ipset.netfilter.org/), a user-space hash table for iptables:

x----x----x----x_____________________________________x----x_____________________________________x----x----x----x
	# create a new set for individual IP addresses
	ipset -N tor iphash
		# get a list of Tor exit nodes that can access $YOUR_IP, skip the comments and read line by line
		wget -q https://check.torproject.org/cgi-bin/TorBulkExitList.py?ip=$YOUR_IP -O -|sed '/^#/d' |while read IP
	do
	  	# add each IP address to the new set, silencing the warnings for IPs that have already been added
  		ipset -q -A tor $IP
	done
		# filter our new set in iptables
		iptables -A INPUT -m set --match-set tor src -j DROP
x----x----x----x_____________________________________x----x_____________________________________x----x----x----x