🚀 go-pugleaf

Hello,

I first post a message which main subject was :

>I first apologize for this cross-posting (and for my poor english),
>but I *really* need a quick answer and I think the newsgroups I choose
>are all corresponding to my question. 
>[...]
>So, here is my question : is there a way to use Linux (whatever the
>kernel is 1.2.13 or 2.0.0 or 2.1) as a routing / filtering machine ?
>I'd like to be able at least to filter incoming / outgoing IP adresses
>and port if possible.
>
>Maybe should I recompile (again ;-) the Kernel with modifications in
>the /inet/* sources ? Which one ?
>[...]

I really thank you for all the response I received !

I asked in my previous post for an e-mail reply because I only had
mail access at my job but I promised to publish the answers.

Here they are (breefly) : 

There were two kind of answers :
1/
It is possible to have IP filtering with 'ipfwadm'
You can find information about it in every webcrawler. It is in fact a
kind of shell for all ip_fw.c subprograms. It helps to maintain 3
files in /proc/net : ip_acct, ip_block and ip_forward.
The possibilities offered by this 3 files are kernel dependant. So
there are 2 release versions of ipfwadm : one for kernel version  >=
1.2.1 and one for kernel version >= 2.0.

This kind of IP filtering is done by the kernel. It looks to be quit
secured. I'm I wrong ? (note : you have to compile the kernel with
some special options. See any ipfwadm doc)

There are others filtering possibilities done by upper layer softwares

2/
It is also possible to filter IP with TIS or SOCKS or tcpwrapper (tcpd
?) or maybe others. These are in fact 'proxies' so they are listening
on certain port and filter IP packets then.
I didn't look further out about TIS because I currently working on a
routing/filtering Linux box. So I can't say more for the moment but
I'll certainly use it later.

tcpd is the standard software distributed with linux which is
configured in /etc/inetd.conf and uses 2 configuration files
/etc/hosts.allow and /etc/hosts.deny. Man pages are simple to
understand. Is tcpd enough to protect for un-wished connections ?


Didn't I make any mistake ?? please tell me (this time, don't mail.
everybody should be inform of something wrong)


So, thank you very much for helping me, particulary to :
- Samuel Tardieu <sam@inf.enst.fr>
- Etienne Bernard <eb@eb.via.ecp.fr>
- dplatt@iq.navio.com
- Jonathan Loh <jloh@scorpion.sirius.com>
- dan@experts-exchange.com (Dan Gardner)
- Jan-Peter Wilhelms <jp-wilhelms@itsec-debis.de>
- Robert Millner <millner@millner.bevc.blacksburg.va.us>
- R I Bagnall <menrib@sun.leeds.ac.uk> (thanks for your forwarding,
compare your quote with his  :-) (I can translate it if needed)


******* ******* ******* ******* ******* ******* ******* ******* 
I'm now looking for any ipfwadm configuration files samples ! If you
have some, could you send to me please (by mail, same reason) ?
******* ******* ******* ******* ******* ******* ******* ******* 


A special note for merrion@pobox.com (french) :
Vous avez dit : 
>PS: follow-up dans les news fran�aises parce que moi j'cause fran�ais.
>
Lorsque l'on post en reply, tous les groupes de news ayant recus le
post initial recoivent la reponse (c'est du moins ainsi qu'est
configure votre lecteur de news). En conscequence, votre reponse m'est
correctement parvenue par mail, merci, mais aussi a tous les groupes
que j'avais choisis pour mon cross-posting. Moyennant quoi, votre
reponse, je cite,  'dans les news fran�aises parce que moi j'cause
fran�ais', a gentiment ete postee dans les news en langue anglaise.
Vous n'avez pas honte ? :-P




Charles DELORME          __   delorme@worldnet.net
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Today's quote : Dans /dev/null personne ne vous entend crier...