p0f, bpf, and jail
kudzu at tenebras.com
Thu Jul 11 14:51:21 UTC 2019
p0f, tcpdump, etc. will not normally work in a jail – this is by design.
The packet filter device is hidden, and not normally presented in the
There are discussion in the Forums on how to do this. "bpf not available in
freebsd jail" is a useful Google search term.
On Thu, Jul 11, 2019 at 7:28 AM David Mehler <dave.mehler at gmail.com> wrote:
> I'm using FreeBSD 12 on amd64 hardware. p0f is passive os
> fingerprinting, what I'm wanting to do is determine by passively
> analyzing a connecting machines tcp stack what kind of machine it is,
> and based on that result add in an email header to the message. So,
> for example if someone connects to my system by means of an xp laptop
> and tries to send email, I'll know by that email header the type of
> connecting machine. Later down the antispam chain the antispam
> software can take an action most likely a silent drop, based on that
> On 7/10/19, Ernie Luzar <luzar722 at gmail.com> wrote:
> > David Mehler wrote:
> >> Hello,
> >> Is anyone using p0f in a jail on FreeBSD 12? I'm getting two errors
> >> one about bpf not being available, the other about how the jail is
> >> trying to sniff the host's network interface. The tcpdump-type
> >> expression is 'tcp dst 1515'
> >> Thanks.
> >> Dave.
> >> _______________________________________________
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> > I see you have gotten no replies. This maybe to the lack of any details
> > provided by you. You will get better results if you provide details
> > about what your trying to do, what hardware you are using and what
> > version of FreeBSD you are running. BY default bpf is disabled for
> > jails. Have no idea what pof is.
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