On Sun, Jun 11, 2017 at 8:48 AM, Stefan Seefeld via Boost < boost@lists.boost.org> wrote:

On 11.06.2017 04:33, Daniel James via Boost wrote:

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On 10 June 2017 at 21:28, Vladimir Prus via Boost <boost@lists.boost.org> wrote:

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Hi,

it seems that most of recent posts to the mailing lists have rather strange "From" field, e.g.

From: Daniel James via Boost <boost@lists.boost.org>

I see this problem both via NTTP and regular mail, including emails that appear to be posted directly with a mail client.

That extra "via Boost" adds no value, and clutters mailbox. Is there any change to return back to having "From" field have just the name of the person?

+1

The "From:" field could contain the full address of the original poster, not just his name. That's how things were before the change, IIUC. But, AFAIU, that had to change because some mail servers would refuse to serve mail whose "From:" address differed from the "sender" field (which is the list address in our case). Am I describing this correctly ? I wonder how others handle this situation (in particular, how mailman and similar tools deal with this themselves), given how frequent a use-case this is...

They deal with it by not setting "Sender:" at all. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

On Sun, Jun 11, 2017 at 4:00 PM, Rene Rivera via Boost <boost@lists.boost.org> wrote:

They deal with it by not setting "Sender:" at all.

Doesn't that run into problems with SPF? -- Olaf

On 12/06/2017 23:32, Michael Caisse via Boost wrote:

On 6/11/17 06:48, Stefan Seefeld via Boost wrote:

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The "From:" field could contain the full address of the original poster, not just his name. That's how things were before the change, IIUC. But, AFAIU, that had to change because some mail servers would refuse to serve mail whose "From:" address differed from the "sender" field (which is the list address in our case). Am I describing this correctly ? I wonder how others handle this situation (in particular, how mailman and similar tools deal with this themselves), given how frequent a use-case this is...

Stefan

With the old system, many people were having issues with DMARC filtering emails as-if they were spoof'd. In the recent couple years many corporate accounts have moved to utilize DMARC as part of their inbound authentication and the popularity continues to increase.

Unfortunately, Mail Lists normally break because the original sender's domain DKIM signature doesn't match the Mail List. The most popular work around is rewriting the From header field. We are doing that in the most basic manner.

Hi Michael, thanks for the explanation. So, if I understand correctly, the problem is that some *senders* have their domains configured to ask recipients to reject emails that don't pass DKIM or SPF? In other words, the question is not how many organizations have DMARC for inbound authentication, but how many users are sending emails to a mailing list (which, by definition, forwards email with modifications) while also requesting than any forwared with modifications emails are rejected by recipients? How many such sending users/domains do we have? I personally think it would be reasonable to just require that posters don't use such domain configuration. If that's not possible, can't we make Mailman not add any footers, and don't add any DKIM signature of its own. Maybe, that will cause original DKIM signature to remain valid and DMARC check to pass? Thanks, Volodya

On 13/06/2017 14:59, Olaf van der Spek via Boost wrote:

On Tue, Jun 13, 2017 at 10:22 AM, Vladimir Prus via Boost <boost@lists.boost.org> wrote:

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thanks for the explanation. So, if I understand correctly, the problem is that some *senders* have their domains configured to ask recipients to reject emails that don't pass DKIM or SPF? In other words, the question is not how many organizations have DMARC for inbound authentication, but how many users are sending emails to a mailing list (which, by definition, forwards email with modifications) while also requesting than any forwared with modifications emails are rejected by recipients? How many such sending users/domains do we have?

I personally think it would be reasonable to just require that posters don't use such domain configuration.

Doesn't gmail also use dmarc?

It does, as can be seen at https://dmarcian.com/dmarc-inspector/gmail.com But that configuration (p=none) asks recipient servers to report back to gmail about any problems they see, not drop email, whereas some other email providers have "p=reject".

...

If that's not possible, can't we make Mailman not add any footers, and don't add any DKIM signature of its own. Maybe, that will cause original DKIM signature to remain valid and DMARC check to pass?

The original From header is still problematic AFAIK.

It is my understanding that if you don't modify From header and don't modify body, then DKIM will pass and SPF will fail, and it's enough for one of the tests to pass. - Volodya

On 14/06/2017 01:17, Michael Caisse via Boost wrote:

On 6/13/17 01:22, Vladimir Prus via Boost wrote:

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On 12/06/2017 23:32, Michael Caisse via Boost wrote:

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On 6/11/17 06:48, Stefan Seefeld via Boost wrote:

...

The "From:" field could contain the full address of the original poster, not just his name. That's how things were before the change, IIUC. But, AFAIU, that had to change because some mail servers would refuse to serve mail whose "From:" address differed from the "sender" field (which is the list address in our case). Am I describing this correctly ? I wonder how others handle this situation (in particular, how mailman and similar tools deal with this themselves), given how frequent a use-case this is...

Stefan

With the old system, many people were having issues with DMARC filtering emails as-if they were spoof'd. In the recent couple years many corporate accounts have moved to utilize DMARC as part of their inbound authentication and the popularity continues to increase.

Unfortunately, Mail Lists normally break because the original sender's domain DKIM signature doesn't match the Mail List. The most popular work around is rewriting the From header field. We are doing that in the most basic manner.

Hi Michael,

thanks for the explanation. So, if I understand correctly, the problem is that some *senders* have their domains configured to ask recipients to reject emails that don't pass DKIM or SPF? In other words, the question is not how many organizations have DMARC for inbound authentication, but how many users are sending emails to a mailing list (which, by definition, forwards email with modifications) while also requesting than any forwared with modifications emails are rejected by recipients? How many such sending users/domains do we have?

I might have explained poorly. When the ML sends emails, it is the receiving side (inbound) that is doing the check. The receiving server confirms headers, checks the signature against what is in the original sender's domain entries and then fails the message.

According to what I read, only if *sending side* requests to fail the message with "p=reject" in DMARC DNS entry. Is it not true? Also, according to what I read, if ML does not modify any headers and does not modify body, and does not add its own DKIM signature, then DKIM test will pass. Is it not true? At present, it seems that mailing list: - Adds footer (which breaks original DKIM signature) - Adds its own DKIM signature (in fact, two) - Modifies From header to "fix" things up. I am asking whether we've tried to configure Mailman to try not modifying anything at all, and act as close to perfect forwarding as possible.

Some of the organizations/services that utilize DMARC: Microsoft, Yahoo, Pixar, any thing through Rackspace, and gmail.

According to: https://dmarcian.com/dmarc-inspector/outlook.com https://dmarcian.com/dmarc-inspector/exchange.microsoft.com Microsoft has "p=none" as well. Gmail likewise. Only Yahoo has "p=reject".

We are talking about some other solutions... but most of them are horrible or short lived until the entire world moves to DMARC.

I am not 100% sure that Mailman can be configured to keep original DKIM signature valid (and seems like its developers don't know either), but it seems to me that loosing mailing list footer is better than mangling From field, and therefore worth a try? - Volodya

On 6/13/17 01:22, Vladimir Prus via Boost wrote:

If that's not possible, can't we make Mailman not add any footers, and don't add any DKIM signature of its own. Maybe, that will cause original DKIM signature to remain valid and DMARC check to pass?

I meant to respond to this part too: This is what we used to do with the old ML when it was ran by IU. We were dropping thousands of emails a day because of DMARC and we had quite a number of complaints from individuals who used to be involved with the list but could no longer receive emails. As more companies are using DMARC, we will have to find a better solution. michael -- Michael Caisse Ciere Consulting ciere.com

On 14.06.2017 12:15, Olaf van der Spek via Boost wrote:

On Mon, Jun 12, 2017 at 10:32 PM, Michael Caisse via Boost <boost@lists.boost.org> wrote:

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We can consider some other possible changes; however, it is impolite to modify the From field with an address that would indicate an individual but represents the entire list.

Is it?

I get notifications from github with From: User Name <notifications@github.com> It seems like the best solution.

I think it would greatly increase the chance of someone mistakenly sending private mails to the list. That's not an issue with the github mail address. Regards - Asbjørn

On 14.06.2017 13:01, Olaf van der Spek via Boost wrote:

On Wed, Jun 14, 2017 at 12:55 PM, Asbjørn via Boost

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I think it would greatly increase the chance of someone mistakenly sending private mails to the list. That's not an issue with the github mail address.

Why not? If you reply it ends up in the public issue tracker.

In that case it has the same issue, one which I'd consider a defect. YMMV. Regards - Asbjørn