Re: (no subject)

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Thanks, that's also a good idea. I'll try that too :)


On Sat, 2004-02-21 at 19:23, c0ldbyte wrote:
> How about a faster way to do that, that is static to any interface that
> pops up, "iptables -A INPUT -i ! lo --tcp-flags SYN,FIN SYN,FIN -j DROP"
> that will protect every interface that is not lo(Loop Back).
> 
> On Sat, 21 Feb 2004 19:49:22 -0300
> Alexis <alexis@xxxxxxxxxxxx> wrote:
> 
> > A fast way to do this is with a script and something like this (could
> > be a lot of other options and ways to do this)
> > 
> > MY_IP=`ifconfig eth0 | grep "inet addr" | cut -d':' -f2 | cut -d' '
> > -f1`
> > 
> > and then
> > iptables -A INPUT -p tcp -d $MY_IP --tcp-flags SYN,FIN SYN,FIN -j DROP
> > 
> > of course, you need to change eth0 to the interface that you need to
> > obtain an ip address.
> > 
> > If this interface is related to an ppp interface it could be easy, in
> > a file called ip-up in /etc/ppp you could set your script with the
> > following vars
> > 
> > # When the ppp link comes up, this script is called with the following
> > # parameters
> > #       $1      the interface name used by pppd (e.g. ppp3)
> > #       $2      the tty device name
> > #       $3      the tty device speed
> > #       $4      the local IP address for the interface
> > #       $5      the remote IP address
> > #       $6      the parameter specified by the 'ipparam' option to pppd
> > 
> > 
> > pppd executes this script when it comes up
> > 
> > so you can use $1 where i put $MY_IP in the iptables command.
> > 
> > then, if you need to change some parameters when the ppp connection
> > cames down, just set it in ip-down
> > 
> > and thats it
> > 
> > 
> > 
> > 
> > Hello Anthony,
> > 
> > Saturday, February 21, 2004, 9:46:59 AM, you wrote:
> > 
> > AdAL> Hi, I would like to add a certain rule to my firewall, but I have a
> > AdAL> dynamic IP, I'm wondering if there is some way I can work with this
> > AdAL> the line is as follows:
> > 
> > AdAL> iptables -A INPUT -p tcp -d <MyDynamicIP> --tcp-flags SYN,FIN SYN,FIN -j
> > AdAL> DROP
> > 
> > AdAL> Thanks for any information you can provide.
> > 
> > AdAL> --tony
> > 
> > 
> > -- 
> > Best regards,
> >  Alexis                            mailto:alexis@xxxxxxxxxxxx
> > 
> > 
> > 
-- 
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