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An easy firewall management system

LiNuXaDDiKt

An easy firewall management system
« on: May 04, 2005, 05:38:26 AM »
I dont know if I'm the only one on earth :-) that is looking for a firewall management system, but it seems hard to find a distro that includes such tool.

I may well be wrongly informed (maybe there are some tools that just do that) but I think SME-Server could include that.

What do you think?

Rob.

Offline raem

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An easy firewall management system
« Reply #1 on: May 05, 2005, 02:31:11 AM »
At the basic level you already have a firewall management tool, it's called server manager. Instead of tweaking firewall rules directly, you select functions and the appropriate ports are open/closed as required & services enabled/disabled as required.
sme policy is to only have a port open if it is neeeded by the functions you have selected.
Port forwarding is a panel in server manager.

If you need more extensive control then there are port opening contribs & masq manager contribs, search !

If you really want to customise your firewall then you can manipulate firewall rules using masq custom templates, under command line control.

iptables -L to show what's happening

Search here on masq & iptables to find more info.
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LiNuXaDDiKt

An easy firewall management system
« Reply #2 on: May 05, 2005, 03:26:40 AM »
As I understand things, it sounds like it is by design.

My needs are not really to open more ports that are already opened since I'm quite happy with what SME delivers the way it is built.  But, a way to restrict the access to some services to a limited group of known users (mostly on the public side) would be the best solution for me.  By applying specific rules to public services there are less chances for security breaches.

I just want to make sure you dont understand my intervention here as a complain (wich is not).  I really feel that SME is a good distro that fits my home and business needs but there is always room to make things better.

It is mainly a constatation that there is so many packages for about everything that sticks to almost every Linux distribution but I have'nt seen any with a complete, easy to use, free, Web based iptables management system.

I will definitely have a look at your suggestions.

Rob.

floflood

An easy firewall management system
« Reply #3 on: May 08, 2005, 03:01:06 AM »
Hello forum...

as we're about to get SME running for a 10
people office soon, i think it's a good
idea to have a firewall onboard. Maybe it's
a bit of a Windows paranoia, but just
helpful to see which of your computers
software connects to the internet by using
a firewall.

Even if i can close ports manually etc, i
still don't have that kind of control a
firewall provides for the way OUT into the
net. f.e. my last win-xp virus was detected
on it's way OUT, since certain programs are
not allowed to send mails. Actuylly it was
a keyboard tracker-spyer, so i was lucky
detecting it although wondering about my
"sleeping" live virus-detector.

Thanks for your support ..

..what about the IPCop firewall ?

Flo

Offline jackl

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An easy firewall management system
« Reply #4 on: May 09, 2005, 01:22:00 AM »
Hi All,
Check out this contrib:
http://www.muzo.homeip.net/nest/contribs/Rpm/Masq_Manager/

I have used it to create a stealth mode by setting icmp parameters and also blocked an ip address from having any access to our server purely using the spoofed ip address section options.
Only started to use it this weekend but so far it looks great for what I want to do.

Regards
Jack
......

Offline hanscees

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An easy firewall management system
« Reply #5 on: September 01, 2005, 12:35:28 AM »
Quote

In 7.0, all you need to do to open a port is to create a service db record:

config set blah status enabled access public TCPPort nnn

then:

expand-template /etc/rc.d/init.d/masq
/etc/rc.d/init.d/masq adjust

Voila!


I am sorry but I find this really not the point. A good firewall panel is not just about incoming traffic. It is also about restricting traffic outbound and all kinds of other stuuf more. I have my own custom script and don't allow any udp outbound for instance. That restricts internal worms going outside for instance. I do not allow irc and so on.

my script is here:
http://www.hanscees.net/iptables5

But that is just an example (and there are much better ones).
nl.linkedin.com/in/hanscees/

Offline CharlieBrady

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An easy firewall management system
« Reply #6 on: September 01, 2005, 01:37:40 AM »
Quote from: "floflood"

as we're about to get SME running for a 10
people office soon, i think it's a good
idea to have a firewall onboard.


It does have a firewall onboard.

Offline CharlieBrady

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An easy firewall management system
« Reply #7 on: September 01, 2005, 01:40:40 AM »
Quote from: "hanscees"

A good firewall panel is not just about incoming traffic. It is also about restricting traffic outbound and all kinds of other stuuf more.


Well, that depends on the firewall, and the firewall policy. The current SME policy is to allow outbound connections. We'd be happy to have a code contribution which added a panel to the server-manager which allowed that policy to be changed.

Offline calisun

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An easy firewall management system
« Reply #8 on: September 21, 2005, 07:56:27 PM »
Management in SME server is very hard, for that reason I use Linksys routers at all my locations and use SME in server mode only. In SME you don't have DHCP leased ip table and you don't have port forwarding. Many of our people work from home and they need to access their workstations from home or from hotel during business trip. Our workers connect using VNC, and Linksys allows me to forward VNC ports to specific workststions.
SME user and community member since 2005.
Want to install Wordpress in iBay of SME Server?
See my step-by-step How-To wiki here:
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Offline arne

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An easy firewall management system
« Reply #9 on: September 21, 2005, 10:33:52 PM »
I am testing out the SME 7.0 beta 4 just now. I think it can do all the functions mentioned above. Don't know exactely what is meant with: "In SME you don't have DHCP leased ip table" - Well I'm using it's dhcp just now.

"Management in SME server is very hard" No,no - abselutely not - management of the SME server functions is very, very quick and easy.

Have played with Linux for allmost 10 years now, but will still need some monts of debugging before a standard Linux server can run without to much bugs or security risks. With the sme server I can set it up a bether and more secure server in half an hour.

When it cames to firewalling, the SME 7.0 kernel seems to be supporting most of the standard firewalling functions of the 2.6.x kernel including bridging firewall. Any firewall can be easy applied via a standard firewall script.

When it comes to a task like remote controll of diverse workstations can be done via portforwarding trough the standard configuration tools of the server manager. (And of cource som remote controll program like vnc or Windows remote desktop.)

Because of a PPPoA ADSL connection in my home I have a PPPoA nat router I can't get rid of.

I belive a thing that could work in such a case is to forward all ports and protocolls to a sme 7.0 gateway and from there firewalling/forwarding using the standard functions of the sme. Have not tried yet, but guess it will work for individual remote controll of individual work stations as well. (This will eventuelly be a double DNAT, but I still believe it should work.)

I think there is one major problem to implement realy advanced firewalling capabilities to the sme server-admin panel. The concept of the server-manager panel is to automate a lot of complex tasks and this way to make a lot of things very easy.

If you should apply a more advanced firewall, this will also require a lot of new firewall configuration functions. Even though if you used all of the existing menues og the server-admin panel just for firewall configuration, it will still be rather little, compared with the firewalling potencial of the Linux kernel 2.6.x and the SME 7.0. It has the potencial of doing allmost anything.

If you want a clean and easy configuration interface that fit into the server-manager panel, you will be restricted to a few standard firewall configurations because of all the configuration menues that are not there.

My personal point of veiw is that if you want things to be simle and easy to use, things have to be like they are. If you want to make use of some of the meny advanced firewall functions it will be neccessary to build up some aditional configuration tool that is not a part of the server-admin panel. You can not build in a lot of advanced firewall configurations tool and still keep the existing simplicity of the server-manager panel.

One way of doing this could be to build up some kind of interactive (or editable) script that flushes out the existing firewall and replace it with a new firewall with the alternatively wanted properties. Doing it this way will keep the orgianal SME firewall, so there will be allmost no risk. You just reboot the server/gateway and the orginal SME firewall with original firewall configuration will be back.

By the way - including a filtering of outbound trafic of the sme gateway as it is will be a very bad idea. This will require a lot of maintenace and a fine masked configuration tool for the outbound trafic, that is not there. (And that can not be there as long as things should be kept simple.)


Best reg Arne.
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Offline CharlieBrady

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An easy firewall management system
« Reply #10 on: September 21, 2005, 10:50:55 PM »
Quote from: "calisun"

In SME you don't have DHCP leased ip table ...


I don't know why you want to view that table, but there's a contrib to do that.

Quote

and you don't have port forwarding.


I'm afraid you're wrong there.

Offline calisun

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An easy firewall management system
« Reply #11 on: September 21, 2005, 11:23:56 PM »
Quote:
I don't know why you want to view DHCP leased IP table.

Well, it is nice if John calls me and says that he wants to connect to his workstation from home in the next 5 minutes, I just pull up the table to find out what is his workstation IP address, so I can forward port to his computer. Instead of going to his workstation to find out his IP address.
I am sure that there is a way to do that in SME server, but it is not part of "server manager"
Linksys routers have a very nice and easy user interface that I can complete both functions, view table and forward port both under 15 seconds.

As far as port forwarding, you are right. I just have not used that feature since I use Linksys router for my DHCP. Besides, using a router gives another layer of protection for the server itself.
SME user and community member since 2005.
Want to install Wordpress in iBay of SME Server?
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Offline arne

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An easy firewall management system
« Reply #12 on: September 21, 2005, 11:36:14 PM »
I think iptraf is included by default at the sme 7.0 beta 4. With this trafic monitor I think you will normally se the clients that is up and running (as long as it not a big network with a lot of trafic.)

The portsanner nmap can be easy installed via the server-manager panel. With this you can make a quick scan to see the clients.
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Offline arne

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« Reply #13 on: September 21, 2005, 11:48:53 PM »
To ping 254 local ip adresses using nmap:
nmap -sP 10.0.0.1-254
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Offline calisun

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An easy firewall management system
« Reply #14 on: September 22, 2005, 12:20:52 AM »
My issue is, I am running the server headless (no monitor, no keyboard  for security reasons) and we all use MacOS X workstations. So I just fire up my web browser on my workstation, connect to my Linksys router, view tables and configure on the fly. Same thing with SME server, I do all my configuratin from "server manager" I only connect the monitor and keyboard when there is a problem. So far I only had to use it to upgrade, no problems so far..  :-)
SME user and community member since 2005.
Want to install Wordpress in iBay of SME Server?
See my step-by-step How-To wiki here:
http://wiki.contribs.org/Wordpress_Multisite