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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 15:54:47 +0200	[thread overview]
Message-ID: <20200927135447.GA8628@salvia> (raw)
In-Reply-To: <rko3n2$jjm$1@ciao.gmane.io>

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)

  parent reply	other threads:[~2020-09-27 13:54 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 [this message]
2020-09-27 14:03   ` Pablo Neira Ayuso
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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