Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 06 Dec 2009 18:01:16 -0500
From:      Tom Uffner <tom@uffner.com>
To:        Torsten Kersandt <torsten@cnc-london.net>
Cc:        freebsd-pf@freebsd.org
Subject:   Re: Limit connections doesn't work
Message-ID:  <4B1C37BC.1010104@uffner.com>
In-Reply-To: <015501ca768f$a42353e0$ec69fba0$@net>
References:  <6783768.102251260022192330.JavaMail.root@zimbra-store>	<4B1BAF1D.9070105@gmx.de> <015501ca768f$a42353e0$ec69fba0$@net>

next in thread | previous in thread | raw e-mail | index | archive | help
Torsten Kersandt wrote:
> HI 
> I personally have all ssh and alike ports closed on my servers.
> If I want to connect to the server per ssh or whatever function, I login to a hidden php which adds my current IP to a sql table.
> I use sql because I'm not the only one using this and want to keep track which admin is logging in.
> A cron job is running every minute looking in the table and adding the new ip addresses to the pf include file and reloading PF
> 
> Every night at 4am, I empty the text file and reload pf.
> 
> I know that this could be done more elegant but KISS is what I like.

that script is horribly inefficient and disruptive to your firewall
throughput.

you could save a lot of unnecessary cpu cycles and speed up your
connections a bit by simply replacing the reloads with pfctl
commands that manipulate the table directly.

> #!/bin/sh
> ### MySQL Setup ###
> MUSER="username"
> MPASS="password"
> MHOST="localhost"
> MYSQL="/usr/local/bin/mysql"
> #
> ### Get all new IP addresses ###
> DBS="$($MYSQL -u $MUSER -h $MHOST -p$MPASS -Bse 'select ipAddress from intranet.ipCleared WHERE `timestamp` > (UNIX_TIMESTAMP()-60)')"
> for ip in $DBS
> do
>  ## this bit is emailed to me over cron run-output if a new IP address was found
>  echo $ip >> /usr/local/etc/pf/pf.VNCallow
>  echo "Added $ip to VNC Access from MYSQL Table"
>  /etc/rc.d/pf reload
> done

that loop at the end is anything but KISS.

select the new addresses and add them to the table with something like

pfctl -t VNCallow -T add $DBS

instead of that do loop. for persistence across reboots, select all the
address in your SQL table & add them to the pf table when pf starts.
clear the table with

pfctl -t VNCallow -T flush



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4B1C37BC.1010104>