Enhance README

README.md

@@ -3,3 +3,35 @@
 iblock is an inetd program adding the client IP to a Packet Filter table.
 
 It is meant to be used to block scanner connecting on unused ports.
+
+
+# How to use
+
+Start inetd service with this in `/etc/inetd.conf`:
+
+```
+666 stream tcp nowait root /usr/local/bin/iblock iblock
+```
+
+Use this in `/etc/pf.conf`, choose which ports will trigger the ban from the variable:
+
+```
+# services triggering a block
+blocking_tcp="{ 3306 5432 3389 27019 }"
+
+table <blocked> persist
+
+pass in quick on egress proto tcp to port $blocking_tcp rdr-to 127.0.0.1 port 666
+block in quick from <blocked>
+```
+
+Done! You can see IP banned using `pfctl -t blocked -T show` and iBlock will log blocking too.
+
+
+# TODO
+
+- make install doing something
+- A proper man page
+- Support IPv6
+- make it work with doas
+- pf table as a parameter