README: usage

README.md

@@ -1,6 +1,8 @@
 # AutoFW
 
-Inspired by fail2ban.
+This tool is inspired by fail2ban.
+
+Assumes UFW for now.
 
 ## Building
 
@@ -10,3 +12,13 @@ apt-get install -y cmake libpcre2-dev
 cmake .
 make
 
+## Usage
+
+1. Create a file autofw.whitelist, containing IP addresses and ranges that should always be allowed to connect.
+1. Collect all IP addresses and ranges to block into a new file, say `autofw.badips`. It may be a good idea to filter out entries in the whitelist.
+1. Run `ufw insert 1 deny from $ip` for each entry in `autofw.badips`. The ufw tool will automatically ignore duplicates.
+1. Collect all blacklisted addresses using the following command:
+``ufw status verbose | grep DENY | awk '{print $4}' > autofw.blacklist``
+1. Run `./autofw > ufw.updates`.
+1. Run the `ufw.updates` script.
+