----- Original Message -----
> From: "José Ferreira" <[email protected]>
> To: [email protected]
> Sent: Thursday, November 27, 2014 3:34:57 AM
> Subject: [dmarc-ietf] DMARC and Bounces (was: Indirect Mail Flows)
> 
> >From: "Franck Martin" <[email protected]>
> >Sent: Wednesday, November 26, 2014 10:29:35 PM
> >
> >Therefore it is important to read
> >http://trac.tools.ietf.org/html/rfc7208#section-10.1.3 on how to setup SPF
> >to work with >bounces.
> >
> >I know (or have known) several large properties that did not have this
> >setup. Unfortunately, bounces are not very visible >and it is hard to stop
> >sending emails to an invalid address if you cannot receive bounces due to
> >policy.
> 
> So let's see how this must work in bounces ( DSN ):
> 
> Requirements:
>  * For the domain, the RFC5321.EHLO/HELO domain is used if the
>  RFC5321.MailFrom is null.
>  * RFC5321.MailFrom must have a domain.
>  * alignment must exits between RFC5321.MailFrom domain, SPF identifier
>  domain and DKIM's d= value.
> 
> So a DMARC compliant DSN must:
>  * Have a RFC5321.MailFrom with domain
>  * Must present a HELO/EHLO hostname aligned  domain and/or DKIM sign with d=
>  of the same domain.
> 
> 
> Considerations:
>  * This can be tricky in strict mode. Probably we should define a new
>  specific field to define how this should align.
>  * Some MTAs, at least Postfix, by default generate bounces with "From:
>  MAILER-DAEMON (Mail Delivery System)".
> 
RFC5321.From (envelope from) must be a valid email address or be null <>

RFC5322.From must have a domain (the From Header, not the envelope From 
RFC5321):
http://tools.ietf.org/html/rfc5322#section-3.6.2
http://tools.ietf.org/html/rfc5322#section-3.4

   from            =   "From:" mailbox-list CRLF

   mailbox-list    =   (mailbox *("," mailbox)) / obs-mbox-list

   mailbox         =   name-addr / addr-spec

   name-addr       =   [display-name] angle-addr

   angle-addr      =   [CFWS] "<" addr-spec ">" [CFWS] /
                       obs-angle-addr

   addr-spec       =   local-part "@" domain

As such the construct you indicate is illegal:
From: MAILER-DAEMON (Mail Delivery System)

http://www.postfix.com/bounce.5.html, it is indeed a problem with postfix out 
of the box and empty_address_recipient needs to be configured properly.

Note: this rule for RFC5322.From may be relaxed by RFC6854 for EAI/SMTPUTF8 
compatibility reasons only during the transition.

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