xinetd ipop3d & dns lookups

xinetd ipop3d & dns lookups

Post by saul » Fri, 27 Jul 2001 22:45:52



Hi all

here is my pblm : when a user is connecting to my mail server (using telnet
port 110 or outlook for ex), it's waiting a long long time before allowing
auth and catching mails.
I think that xinetd or ipop3d makes a dns lookup before processing, instead
of just reading /etc/hosts.

How could I tell xinetd or ipop3d not to use DNS and just allow my mail
serer to walk normally (without having to wait for 30 seconds each time)

Thx a lot

 
 
 

xinetd ipop3d & dns lookups

Post by Dean Thompso » Fri, 27 Jul 2001 22:48:34


Hi!,

Quote:> here is my pblm : when a user is connecting to my mail server (using telnet
> port 110 or outlook for ex), it's waiting a long long time before allowing
> auth and catching mails.
> I think that xinetd or ipop3d makes a dns lookup before processing, instead
> of just reading /etc/hosts.

> How could I tell xinetd or ipop3d not to use DNS and just allow my mail
> serer to walk normally (without having to wait for 30 seconds each time)

It is part of the xinetd process.  Some people have reported success by
editing the "pop" definition files located in the directory /etc/xinetd.d.
Once they load the pop files up, they remove all references to the USERID
directive.  Once you have saved the file, re-load the xinetd service and see
whether that improves your access times.

See ya

Dean Thompson

--
+____________________________+____________________________________________+

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xinetd ipop3d & dns lookups

Post by saul » Sat, 28 Jul 2001 02:06:08


Hi Dean, thx for replying

Quote:> > here is my pblm : when a user is connecting to my mail server (using
telnet
> > port 110 or outlook for ex), it's waiting a long long time before
allowing
> > auth and catching mails.
> It is part of the xinetd process.  Some people have reported success by
> editing the "pop" definition files located in the directory /etc/xinetd.d.

I already tried to : removing USERID, writing HOST, removing whole line,
etc...
but no way.

Quote:> Once they load the pop files up, they remove all references to the USERID
> directive.  Once you have saved the file, re-load the xinetd service and
see
> whether that improves your access times.

I found an alternate solution : /etc/named.conf was not properly setup :

====> Jul 26 18:33:35 ns1 named[18897]:
unapproved query from [127.0.0.1].1525 for "25
4.11.168.192.in-addr.arpa"
Jul 26 18:34:08 ns1 ipop3d[19798]: pop3 service init from 192.168.11.254
Jul 26 18:34:08 ns1 ipop3d[19798]: Login user=william
host=skynet.blondeaux-etage.fsc-france.com [192.168.11.4] nmsgs=0/0
Jul 26 18:34:08 ns1 ipop3d[19798]: Logout user=william
host=skynet.blondeaux-etage.fsc-france.com [192.168.11.4] nmsgs=0 ndele=0

I allowed my PCs to make queries on "254-arpa-I-dont-know-what", but the
problem is that I'm not supposed to have a working dedicated DNS on the LAN.
There must be another solution to prevent ipop3d from querying a DNS, it
should just read /etc/hosts in fact.

I EVEN tried to use old inetd daemon, but the problem stays the same, so
it's ipop3d which has to be incriminated :)
I don't understand, cause it walked on my last installation (from a Mdk 7.2)
without changing a lot of security related params.

However, I hope this little alternative (allowing queries) will help some
other users here.

Cu

 
 
 

xinetd ipop3d & dns lookups

Post by Dean Thompso » Sat, 28 Jul 2001 09:10:29


Hi!,

Quote:> I allowed my PCs to make queries on "254-arpa-I-dont-know-what", but the
> problem is that I'm not supposed to have a working dedicated DNS on the
> LAN. There must be another solution to prevent ipop3d from querying a DNS,
> it should just read /etc/hosts in fact.

Nope, when performing a reverse lookup, you will find that the /etc/hosts file
is not trusted/consulted but the system rather takes its responses from a DNS
server instead.  From a security perspective I can understand why it does
this.

Quote:> I EVEN tried to use old inetd daemon, but the problem stays the same, so
> it's ipop3d which has to be incriminated :)
> I don't understand, cause it walked on my last installation (from a Mdk
> 7.2) without changing a lot of security related params.

> However, I hope this little alternative (allowing queries) will help some
> other users here.

Well, if you have a DNS within your own network, then I would use it.

See ya

Dean Thompson

--
+____________________________+____________________________________________+

| Bach. Computing (Hons)     | ICQ     - 45191180                         |
| PhD Student                | Office  - <Off-Campus>                     |
| School Comp.Sci & Soft.Eng | Phone   - +61 3 9903 2787 (Gen. Office)    |
| MONASH (Caulfield Campus)  | Fax     - +61 3 9903 1077                  |
| Melbourne, Australia       |                                            |
+----------------------------+--------------------------------------------+

 
 
 

1. xinetd/ipop3d: how do i turn off the dang logging?

Redhat 7.2, xinetd, ipop3d.

When a client connects to port 110 three lines are logged to the
maillog about his connection: init, login, and logout.  I tried
to
redirect the logging to /var/log/pop.log but it creates the file,
leaves
it 0 byte, and continues loggin to maillog.

Below is xinetd.conf (and the included ipop3 file).  How do I
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it from logging to syslog?  How do I get it to log to my file?

defaults
{
        instances               = 60
        log_type                = SYSLOG authpriv
        log_on_success          = HOST PID
        log_on_failure          = HOST
        cps                     = 25 30

includedir /etc/xinetd.d

##### from included file #####
service pop3
{
        socket_type             = stream
        wait                    = no
        user                    = root
        server                  = /usr/sbin/ipop3d
        only_from               = 10.0.2.0
        log_type                = FILE  /var/log/pop.log
        log_on_success          = PID HOST USERID EXIT DURATION
        log_on_failure          = HOST USERID ATTEMPT RECORD

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