Whitelist IP addresses based on SSH origin

Here is how you create a list of IP addresses, to be used with NGINX, based on successful ssh connections.

$ cat /usr/bin/auth-list.sh

#!/bin/bash
WHITELIST=/etc/nginx/conf/whitelist.conf

# Make sure that we don't add it more than once.
if ! grep -q $PAM_RHOST $WHITELIST; then
	echo allow $PAM_RHOST\; >> $WHITELIST
fi

$ cat /etc/pam.d/sshd

session optional pam_exec.so seteuid /usr/bin/auth-list.sh

Login via ssh and it will add your external IP address to the list.

$ cat /etc/nginx/conf/whitelist.conf

allow 208.67.222.222;
allow 208.67.220.220;

Reload NGINX for it to take affect.

13 Aug 2016