Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 29 Apr 1999 14:55:05 +1000
From:      Andrew Johns <A_Johns@TurnAround.com.au>
To:        hjcs@home.com
Cc:        Guy Helmer <ghelmer@scl.ameslab.gov>, freebsd-questions@FreeBSD.ORG
Subject:   Re: ipfw rules
Message-ID:  <3727E629.275F333F@TurnAround.com.au>
References:  <Pine.SGI.4.10.9904281932230.4039-100000@demios.scl.ameslab.gov> <3727B56C.2D8D0ED1@home.com> <3727D06A.23DECCAA@TurnAround.com.au> <3727E51B.6B0C7935@home.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Christoff Snijders wrote:
> 
> Andrew Johns wrote:
> >
> 
> [snip]
> 
> >
> > What you could try is to enable logging - when I was unsure of what
> > was happening, I retained the existing rules that I was using and
> > added a rule such as:
> > ipfw add 65530 deny log all from any to any
> 
> [snip]
> 
> Great idea!  I did this, but now my problem is that I don't know how to
> interpret the output, or what I should do about what I see.
> 
> There are only two entries in the log file, repeated 50 times each,
> before the logger stops for that rule. The entries read:
> 
> Apr 28 21:13:15 hostname /kernel: ipfw: 63000 Deny UDP 0.0.0.0:68
> 255.255.255.255:67 in via ed2
> Apr 28 21:13:15 hostname /kernel: ipfw: 63000 Deny UDP 123.456.78.123:68
> 255.255.255.255:67 in via ed2
> Apr 28 21:13:15 hostname /kernel: ipfw: limit reached on rule #63000
> 
> I don't really know what this means, but I tried adding the following
> rules in the appropriate place in the rule set, but they did not work.
> Assume that my IP address is 111.111.111.111:
> 
> ipfw add allow udp from 0.0.0.0 to 111.111.111.111 in via ed2
> ipfw add allow udp from 123.456.78.123 to 111.111.111.111 in via ed2
> 

Eeek! Never allow something in until you know what it is. 
http://www.con.wesleyan.edu/~triemer/network/docservs.html identifies
port 68 as the bootp client port - so it looks as though someone is
trying to boot their machine from yours - I could be wrong on this -
anybody else have any ideas? (I'm unaware of any potential security
probs with bootp, although I've done no searching to find out either
:) )

-- 
Regards                        |  _/\_/\
Andrew Johns BSc (Comp Sci)    | /      \
TurnAround Solutions Pty Ltd   | \_...__/
http://www.turnaround.com.au/  |      \/

"The box said 'Requires Windows 98, NT, Linux or better' so I
installed FreeBSD."


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3727E629.275F333F>