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Re: [ietf-smtp] SMTP Over TLS on Port 26 - Implicit TLS Proposal

Viruthagiri Thirumavalavan <giri@dombox.org> Wed, 09 January 2019 03:12 UTC

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From: Viruthagiri Thirumavalavan <giri@dombox.org>
Date: Wed, 09 Jan 2019 08:41:55 +0530
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To: Mark Andrews <marka@isc.org>
Cc: ietf-smtp@ietf.org
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Subject: Re: [ietf-smtp] SMTP Over TLS on Port 26 - Implicit TLS Proposal
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>
> So the snooper just makes a connection over port 26 to the server to fill
> in the missing
> information if they want it.


Ok I missed that one. Good point.

I'm not sure whether all snoopers would know all these loopholes.

You already mentioned "No" to this proposal. If anything else following
this thread, please let me know where you stand.

Thanks

On Wed, Jan 9, 2019 at 8:33 AM Mark Andrews <marka@isc.org> wrote:

>
>
> > On 9 Jan 2019, at 1:59 pm, Viruthagiri Thirumavalavan <giri@dombox.org>
> wrote:
> >
> > The point is that when it's *that* easy to get the information
> indirectly, you're
> > not providing actual security, you're providing security theater.
> >
> > It's not *that* easy. And that's my whole point. There are ptr records
> that points to in-addr.arpa rather than real domain.
> > But if you believe this proposal is pointless, then I'll take your vote
> as "No" for this proposal.
>
> So the snooper just makes a connection over port 26 to the server to fill
> in the missing
> information if they want it.
>
> > Thanks
> >
> > On Wed, Jan 9, 2019 at 8:08 AM <valdis.kletnieks@vt.edu> wrote:
> > On Wed, 09 Jan 2019 07:38:14 +0530, Viruthagiri Thirumavalavan said:
> >
> > > Not every PTR queries resolves to the correct domain.
> > >
> > > 74.125.129.26 => jm-in-f26.1e100.net (A google IP address, but point
> to a
> > > different domain owned by google)
> > >
> > > I would be ok with indirectly someone getting the info rather than
> directly
> > > providing it.
> >
> > The point is that when it's *that* easy to get the information
> indirectly, you're
> > not providing actual security, you're providing security theater.
> >
> >
> > --
> > Best Regards,
> >
> > Viruthagiri Thirumavalavan
> > Dombox, Inc.
> > _______________________________________________
> > ietf-smtp mailing list
> > ietf-smtp@ietf.org
> > https://www.ietf.org/mailman/listinfo/ietf-smtp
>
> --
> Mark Andrews, ISC
> 1 Seymour St., Dundas Valley, NSW 2117, Australia
> PHONE: +61 2 9871 4742              INTERNET: marka@isc.org
>
>

-- 
Best Regards,

Viruthagiri Thirumavalavan
Dombox, Inc.

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