Banning posts by certain From/Sender/Reply-To mailbox strings.
D. Stussy
mailbox/usenetID in From, Sender, and Reply-To headers as a
troll-elimination policy:
@*.localdomain - where "localdomain" is the TLD. An obvious
misconfiguration, since the user is supposed to substitute their actual
domain in place of a literal "localdomain" string.
@localhost - Everyone is a localhost, so another misconfiguration.
Especially true for a "Reply-To:" header field.
@example.* - where "example" is a RESERVED word for a second-level domain
element that is supposed to appear in RFCs and standards documents only and
never on the live Internet.
Killing these strings has had a good effect in ridding certain newsgroup of
their trolls. However, I have also noted an occasional non-troll using an
address matching one of these patterns, so there is an occasional false
positive. Shouldn't any legitimate user who wishes to properly hide his
true address be using the reserved TLD of ".invalid" (except for
"example.invalid")?
Ralf Döblitz
[...]
> @example.* - where "example" is a RESERVED word for a second-level doma=
in
> element that is supposed to appear in RFCs and standards documents only=
and
> never on the live Internet.
ITYM SLDs example.com, example.net and example.org only, no others
second level domains are claimed by RFC2606. Rejecting e.g. example.de
(which is a perfectly valid and registered domain) would be a bad idea.
Ralf
--=20
Ralf D=C3=B6blitz * Schapenstra=C3=9Fe 6 * 38104 Braunschweig *=
Germany
Phone: +49-531-2361223 Fax: +49-531-2361224 mailto:doeblitz@doeblitz.n=
et
Homepage: http://www.escape.de/users/selene/
Mit UTF-8 kann man gleichzeitig =C3=A4=C3=B6=C3=BC=C3=9F=C3=84=C3=96=C3=9C=
=C3=A6=C5=93=C5=82=C3=B8=E2=80=B1=C2=BC=C2=BD=C2=BE=C2=A4=C2=B9=C2=B2=C2=B3=
=C2=A2=E2=82=AC=C2=A3=C2=A5=C2=B6=C2=A7=C2=AC=C3=B7=C3=97=C2=B1=C2=A9=C2=AE=
=E2=84=A2=C2=A1=C2=BF verwenden=E2=80=A6
D. Stussy
news:gpm9qb$nvc$1...@msgid.netzverwaltung.net...
> D. Stussy <sp...@bde-arc.ampr.org> wrote:
> [...]
> > @example.* - where "example" is a RESERVED word for a second-level
> > element that is supposed to appear in RFCs and standards documents only
> > never on the live Internet.
>
> ITYM SLDs example.com, example.net and example.org only, no others
> second level domains are claimed by RFC2606. Rejecting e.g. example.de
> (which is a perfectly valid and registered domain) would be a bad idea.
OK, but I have found that "example" is often a reserved word in the ICANN
TLD agreements, so you're correct that the RFCs by themselves may not cover
it. I do note that you are correct that "example.de" exists within the
DNS, but I have doubts to whether it's a live domain. Example.info exists
as a registered domain (reserved to ICANN itself) but is missing from the
DNS.
So far, it turns out that "example.com" and "example.invalid" are the only
two I've seen in my logs since I implemented the filter. I have also seen
posts with explict "Reply-To:" headers specifying ...@localhost. Why fake
a "Reply-To" header (as opposed to omitting it)?
Actual log entry snippets:
Banned Reply-To address: @localhost
Banned Reply-To address: @example.invalid
Ralf Döblitz
> "Ralf D=C3=83=C2=B6blitz" <doeb...@doeblitz.net> wrote in message
> news:gpm9qb$nvc$1...@msgid.netzverwaltung.net...
>> D. Stussy <sp...@bde-arc.ampr.org> wrote:
>> [...]
>> > @example.* - where "example" is a RESERVED word for a second-level
> domain
nly
> and
>> > never on the live Internet.
>>
>> ITYM SLDs example.com, example.net and example.org only, no others
>> second level domains are claimed by RFC2606. Rejecting e.g. example.de
>> (which is a perfectly valid and registered domain) would be a bad idea.
> OK, but I have found that "example" is often a reserved word in the ICA=
NN
> TLD agreements, so you're correct that the RFCs by themselves may not c=
over
> it. I do note that you are correct that "example.de" exists within the
> DNS, but I have doubts to whether it's a live domain.
The website shows a logo and an "under construction" notice, but it also
mentions a mail address in the same domain, so it is a live domain at
least to some degree.
D. Stussy
news:gpoqk7$pir$1...@msgid.netzverwaltung.net...
> D. Stussy <sp...@bde-arc.ampr.org> wrote:
> > "Ralf D=C3=83=C2=B6blitz" <doeb...@doeblitz.net> wrote in message
> > news:gpm9qb$nvc$1...@msgid.netzverwaltung.net...
> >> D. Stussy <sp...@bde-arc.ampr.org> wrote:
> >> [...]
> >> > @example.* - where "example" is a RESERVED word for a second-level
domain
> >> > element that is supposed to appear in RFCs and standards documents
> >> > never on the live Internet.
> >>
> >> ITYM SLDs example.com, example.net and example.org only, no others
> >> second level domains are claimed by RFC2606. Rejecting e.g. example.de
> >> (which is a perfectly valid and registered domain) would be a bad
idea.
> >
> > TLD agreements, so you're correct that the RFCs by themselves may not
> > it. I do note that you are correct that "example.de" exists within the
> > DNS, but I have doubts to whether it's a live domain.
>
> The website shows a logo and an "under construction" notice, but it also
> mentions a mail address in the same domain, so it is a live domain at
> least to some degree.
According to the IANA, "example" is a reserved 2LD that should never be
issued.
http://gnso.icann.org/drafts/ICANNandIANA-reserved-names-v.12.pdf
Page 2 - "Table 2: IANA-Related Names" (17 entries). - 6 March 2007
However, with this, one could argue that it doesn't apply to ccTLDs since
they're not enumerated, regardless of IANA's purpose for reserving the
words. Other agreements with the registries may bar it. Therefore, for
the moment, I'll change my regex to:
@.*example\.[a-z]{3,}$
That should let "...@example.de" through if it's ever used on Usenet.
However, the impression I got is that the word "example" is to be reserved
in any and all future agreements, and therefore should never appear on the
live Internet as a 2LD (grandfathered situations excepted). The DE
registry doesn't say when the domain was created, but I bet that if it
didn't already exist, it would be banned as a reserved word.