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	vees	2007-04-28 , 02:41
	Posts: 95 \| Thanked: 6 times \| Joined on Apr 2007 @ the Imperial Homeland	#1

Hi,
Nokia's Internet tablets are pretty secure out of the box, ports are well closed, but a small firewall never hurts. Alas, I have not found one (so far). So here is a small hack:

open an editor and create a file with this inside:

#!/bin/sh
iptables -F
iptables -A INPUT -p all -s 127.0.0.1 -j ACCEPT
iptables -A INPUT -p tcp --syn -j DROP

save it, and make it executable (chmod +x). Then, run it as root.

You will have a very basic, but solid, firewall.

HTH,

VS

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	SeRi@lDiE	2007-04-28 , 09:37
	Posts: 919 \| Thanked: 37 times \| Joined on Aug 2006 @ /dev/null	#2

Thanks for the tip.

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	vees	2007-04-28 , 11:28
	Posts: 95 \| Thanked: 6 times \| Joined on Apr 2007 @ the Imperial Homeland	#3

you are welcome. BTW there are far more advanced iptables scripts out there, but this one being super-easy and short I thought I would share it.
on the down side, this does requier some prospective newbie to install Xterm, get a root account, etc.
I wonder if somebody would write a mini-applet and turn this into a mini-firewall package for the N770/N800
Any ideas?
Kind regards,
VS

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gsagers	2007-04-28 , 13:42
Posts: 245 \| Thanked: 25 times \| Joined on Apr 2007	#4

Thanks, great tip! I'd offer the following change for those who want remote SSH access to their Nokia from anywhere - and if I typed something wrong, please correct me - I'm no iptables guru, but it seems to work here!

Code:

#!/bin/sh
iptables -F
iptables -A INPUT -p all -s 127.0.0.1 -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -p tcp --syn -j DROP

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Ricky-Lee	2008-12-10 , 15:06
Posts: 47 \| Thanked: 10 times \| Joined on Jan 2008 @ UK	#5

Any chance of some one getting a version of iptables with logging working?

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	grog	2008-12-10 , 15:47
	Posts: 546 \| Thanked: 85 times \| Joined on Feb 2008 @ Winnipeg, Canada	#6

Would this have to be rerun after a reboot? If so, it could be slapped as is into an rc file like /etc/init.d/firewall & linked to /etc/rc0.d/S40firewall (for example).

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Ricky-Lee	2008-12-10 , 15:57
Posts: 47 \| Thanked: 10 times \| Joined on Jan 2008 @ UK	#7

Yes it would have to be rerun after a reboot. An yer linking it in that way should work

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	brendan	2008-12-10 , 16:34
	Posts: 531 \| Thanked: 79 times \| Joined on Oct 2006 @ This side of insane, that side of genius	#8

why not just

Code:

vi /etc/sysconfig/iptables

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	grog	2008-12-10 , 16:40
	Posts: 546 \| Thanked: 85 times \| Joined on Feb 2008 @ Winnipeg, Canada	#9

I know nothing about iptables, but wouldn't it be "proper" to issue the above commands in the shell to set up the firewall, then use something like 'iptables-save > /etc/iptables.conf' & then just have the rc script call 'iptables-restore < /etc/iptables.conf'? Or am I making things too complicated, as usual?

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	allnameswereout	2008-12-10 , 17:20
	Posts: 3,397 \| Thanked: 1,212 times \| Joined on Jul 2008 @ Netherlands	#10

Damn, I thought we'd discuss firewall appliances

Originally Posted by grog

I know nothing about iptables, but wouldn't it be "proper" to issue the above commands in the shell to set up the firewall, then use something like 'iptables-save > /etc/iptables.conf' & then just have the rc script call 'iptables-restore < /etc/iptables.conf'? Or am I making things too complicated, as usual?

That is the easy and proper way. Put these commands in rc scripts and you're done.

So, issue these commands as root:

Code:

iptables -F # Clears INPUT, OUTPUT, FORWARD rules
iptables -P INPUT DROP # Change INPUT policy to DROP
iptables -A INPUT -p all -s 127.0.0.1 -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -j ACCEPT

To save current firewall rules (before reboot):

Code:

iptables-save >/etc/iptables.conf

To restore previously last firewall rules (during boot or right after boot)

Code:

iptables-restore </etc/iptables.conf

NOTE you should accept traffic to/from local loopback device instead of 127.0.0.1. You should deny traffic from 127.0.0.1 on network because this can only be spoofed traffic. However, I'm no IPT wizard; I prefer OpenBSD PF.

Keep in mind legit network services such as DHCP traffic and Avahi...

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