Subject: [tcpm] FW: Enabling DMARC workaround code for all IETF/IRTF mailing lists

From: "Scharf, Michael (Nokia - DE/Stuttgart)" <[email-masked]>
Date: Fri, 11 May 2018 11:54:02 +0000

FYI

I believe that, unfortunately, some TCPM list subscribers had issues with this in the past, and e.g. got unsubscribed. That was never a TCPM-specific problem.

I am myself not familiar with the technical details, and TCPM is not the right list to discuss this...

Michael

-----Original Message-----
From: ietf [mailto:[email-masked]] On Behalf Of Alexey Melnikov
Sent: Friday, May 11, 2018 2:00 PM
To: [email-masked]
Subject: Enabling DMARC workaround code for all IETF/IRTF mailing lists

Hi,
Many of you have seen several long discussions thread about DMARC and how it affects use of IETF/IRTF mailing lists.

After testing DMARC workaround code written by Henrik Levkowetz on several high volume IETF and IRTF mailing lists (e.g. CFRG, WebRTC, DMARC, QUIC), the tools team and the IESG decided that Henrik's code should be deployed for all IETF and IRTF mailing lists. In particular the workaround allows people from DMARC p=reject domains to participate in IETF mailing lists, as well as to avoid the problem of recipients being unsubscribed from mailing lists. These 2 issues were the main reasons for developing the DMARC workaround code..

The workaround will be deployed today, May 11th.

Below are some technical details on how the email address rewriting workaround is going to work:

Emails from domains that don't have a p=reject DMARC setting are not going to be affected in any way.

For emails from p=reject domains:

- The From header field of such emails will be rewritten to be under @dmarc.ietf.org domain (which will have a p=none policy). For example, "[email-masked]" email address would become "alexey=[email-masked]". The original From header field will be preserved in the X-Original-From header field, which can be used for automatic message processing by Sieve and Mail User Agents.

Note that the mapping is reversible, so it is possible to send replies or new messages to an original sender by sending them to the corresponding mapped @dmarc.ietf.org email address.

Best Regards,
Alexey