From: Pablo Neira Ayuso <pablo@netfilter.org>
To: sean darcy <seandarcy2@gmail.com>
Cc: netfilter@vger.kernel.org
Subject: Re: rate limit SIP INVITES
Date: Sun, 27 Sep 2020 16:03:56 +0200 [thread overview]
Message-ID: <20200927140356.GA8727@salvia> (raw)
In-Reply-To: <20200927135447.GA8628@salvia>
On Sun, Sep 27, 2020 at 03:54:47PM +0200, Pablo Neira Ayuso wrote:
> On Sat, Sep 26, 2020 at 03:10:24PM -0400, sean darcy wrote:
> > nftables-0.9.6
> >
> > I'm running a VOIP server. There are lots of script kiddies who will bang
> > away with 10/sec SIP INVITES or REGISTERS .
> >
> > In iptables you can match on the string:
> >
> > -A SIP -i eth0 -p udp -m udp --dport 5060 -m string --string "INVITE"
> > --algo bm --from 23 --to 28 -m comment --comment "Catch SIP INVITEs" -j
> > SIPINVITE
> >
> > -A SIP -i eth0 -p udp -m udp --dport 5060 -m string --string "REGISTER"
> > --algo bm --from 23 --to 30 -m comment --comment "Catch SIP REGISTERs" -j
> > SIPREGISTER
> >
> > I'm looking at RAW to do the same:
>
> nft add rule x y udp dport 5060 @th,64,48 0x494e56495445 counter
>
> @th => transport header
> 64 => from bit number 64 (8 bytes after the UDP header)
> 48 => extract 48 bits (6 bytes for INVITE)
@th,offset,length
where offset and length are expressed in bits.
next prev parent reply other threads:[~2020-09-27 14:03 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-26 19:10 rate limit SIP INVITES sean darcy
2020-09-26 20:26 ` sean darcy
2020-09-26 20:34 ` sean darcy
2020-09-26 20:45 ` sean darcy
2020-09-27 13:54 ` Pablo Neira Ayuso
2020-09-27 14:03 ` Pablo Neira Ayuso [this message]
2020-09-27 15:42 ` sean darcy
2020-09-27 19:12 ` Florian Westphal
2020-09-27 20:59 ` Pablo Neira Ayuso
2020-09-28 18:09 ` sean darcy
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