The mailing list for listmasters using Sympa

[David Verdin <address@concealed>]

Indeed.

However, it works very well against phishings.

Le 26/05/2016 à 16:24, Matthew Caron (via sympa-users Mailing List) a écrit :

address@concealed">

Thanks!

I should also mention that it doesn't actually work. The spam
suppression, I mean. Spammers just set up their own mailservers with
their own DNS records and send "legit" email. So, there was a whole
bunch of work which amounted to naught, and the real "solution" is
heuristic matching (SpamAssassin, what used to be Postini but is now
owned by Google, etc.)

On 05/26/2016 10:09 AM, David Verdin wrote:

I loved the way you explained it!

Actually, I will probably steal it from you the next time I have to
speak about it. :-D

Cheers,
David
Le 26/05/2016 à 15:48, Matthew Caron (via sympa-users Mailing List) a
écrit :

Short answer: Because it has to, else things will bounce.

Long (and very biased) answer: A long time ago, in times immemorial,
anyone could send email through any mailserver as anyone. But, then the
spammers came, abusing these open relays, and folks closed them down,
requiring authenticated connections and restricting from whom they would
relay mail. But, this was not enough, and the spam continued, and some
people who were too clever for their own good sought to restrict what
mail their servers would accept by only accepting mail from
preauthorized (via DNS) servers for that domain[1]. This effectively
prevented spoofing of the from: address to come from a different domain
than the one for which the server is one of the MXs, because if the mail
came from address@concealed and wasn't sent from a mailserver listed in the
SPF DNS record by foo.com, then the receiving MX would refuse receipt.
And lo, there was the wailing and gnashing of teeth because mailing
lists had relied on using that very trick to relay mail from address@concealed
to all of the subs, and there were bounces from the @gmail.com and
@aol.com and the misery was great. And thus, the solution was to have
the email always come from the mailing list, and therefore the server
sending the mail was an authorized MX for that domain, and all was well.

You can, however, tune the presentation, as is done on this list, by
going to Edit List Config -> DKIM and scrolling down to the "New From
name format" configuration. Thus, you get things like:

From: "Simone Dal Maso" (via sympa-users Mailing List)
<address@concealed>

Which helps us humans keep track of who said what.

[1] See also:
SPF - https://en.wikipedia.org/wiki/Sender_Policy_Framework
DKIM - https://en.wikipedia.org/wiki/DomainKeys_Identified_Mail
DMARC - https://en.wikipedia.org/wiki/DMARC

Hope this helps and was mildly amusing.

On 05/26/2016 06:40 AM, Simone Dal Maso (via sympa-users Mailing List)
wrote:

Hello,
I'm really happy because now I had managed postfix+sympa working great!
Following the tutorial suggested by the debian documentation was the
solution. Quite long, but works.
Now... I created my first super mailing list. :-)
I have a problem with the from field, because any email arriving to me
has the listName as sender, and not my name.
I suppose it was the sender_anonymous parameter, but it is empty... from
the web interface. How can I solve this?
Thank you!

-- 
A bug in Sympa? Quick! To the bug tracker!
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*David Verdin*
Études et projets applicatifs
 
Tél : +33 2 23 23 69 71
Fax : +33 2 23 23 71 21
 
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--
A bug in Sympa? Quick! To the bug tracker!

David Verdin Études et projets applicatifs
Tél : +33 2 23 23 69 71 Fax : +33 2 23 23 71 21   www.renater.fr	RENATER 263 Avenue du Gal Leclerc 35042 Rennes Cedex

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