Rails - Mar 2005 - How to set ''Return-Path'' in ActionMailer to avoid SPF failure?

I was wondering if there was any way to set the ''Return-Path''
of an
email when using ActionMailer.  Without the ability to set the 
''Return-Path'' of an email, it is impossible to avoid being
labeled as
''spam'' by many SMTP gateways if trying to send mail on
another''s
behalf.  SPF doesn''t care about the ''from'' line in an
email, only the
''Return-Path''.

Why would I want to do that?  Because I am working as a consultant for 
another company, and when responding to bug reports I want to make 
things easier for the users by replying ''from'' the
client''s domain.
Unfortunately, they can''t give me access to their SMTP server
(they''re
afraid to muck with sendmail and so I get ''can not relay'' when
I use
their SMTP gateway).

For example, here are the headers from a mail I sent to myself using 
ActionMailer.  As you can see, Gmail has marked it as ''fail''
(in
''Received-SPF'') :

X-Gmail-Received: aac7ac60620782da0f1e605962a47ceaf022a2d0
Delivered-To: jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
Received: by 10.38.12.43 with SMTP id 43cs8575rnl;
         Tue, 8 Mar 2005 22:51:57 -0800 (PST)
Received: by 10.38.82.76 with SMTP id f76mr547559rnb;
         Tue, 08 Mar 2005 22:51:57 -0800 (PST)
Return-Path: <do-not-reply-5tc4TXWwyLM@public.gmane.org>
Received: from omta16.mta.everyone.net (sitemail2.everyone.net 
[216.200.145.36])
         by mx.gmail.com with ESMTP id 71si394734rna.2005.03.08.22.51.56;
         Tue, 08 Mar 2005 22:51:56 -0800 (PST)
Received-SPF: fail (gmail.com: domain of
do-not-reply-5tc4TXWwyLM@public.gmane.org does not
designate 216.200.145.36 as permitted sender)
Received: from pmta01.mta.everyone.net (bigiplb-dsnat [172.16.0.19])
	by omta16.mta.everyone.net (Postfix) with ESMTP id 301233FDA8
	for <jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>; Tue,  8 Mar 2005
22:51:55 -0800 (PST)
X-Eon-Sig: AQIdLpBCLp0L6UAQSwIAAAAB,99b3d5966c8c0368c842a831fa4ddfdd
Received: from smtp.everyone.net (62.245.95.172 [62.245.95.172])
	by pmta01.mta.everyone.net (EON-AUTHRELAY) with ESMTP id 24AB116D
	for <jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>; Tue, 8 Mar 2005
22:51:55 -0800
Date: Wed, 9 Mar 2005 07:51:53 +0100
From: do-not-reply-5tc4TXWwyLM@public.gmane.org
To: jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
Subject: =Thank you for your bug report
Content-Type: text/plain; charset=utf-8
Message-Id:
<20050309065155.301233FDA8-CkVda1wFVPjdi7ou1J7GeDGekZJkHWME@public.gmane.org>

I tried this:
class MyMailer < ActionMailer::Base
     def my_mail(recipients, post)
       @headers["Return-Path"]      =
"jdeneut-4GWaZ2qAA/nQT0dZR+AlfA@public.gmane.org"
      end
end

but it doesn''t work (trying to set the ''Return-Path''
by playing with
the headers doesn''t work in JavaMail either.  Java has an SMTP wrapper 
for setting ''Return-Path''). I''ve looked in TMail as
well, but didn''t
see it there. Is this even supported in Ruby (setting the 
''Return-Path'')?

  Regards,

Jack DeNeut

Jack DeNeut <jdeneut-4GWaZ2qAA/nQT0dZR+AlfA@public.gmane.org> wrote:
> I was wondering if there was any way to set the
''Return-Path'' of an
> email when using ActionMailer.
I believe this is an MTA configuration issue. If you send the mail
by SMTP, the MTA typically sets the Return-Path header to be the
same as the envelope sender. Afaik, there is no way around this 
without changing the MTA configuration. Talk to your sysadmin.

If you send it with sendmail, some systems allow you to specify
the sender address with the -f option, but this normally means that
the user running the process that sends the mail must be a trusted
user. But I don''t even know if there is a way to specidy the -f option
with ActionMailer.

-- 
Regards,
Stian Grytøyr

On 9 Mar 2005, at 9:37, Stian Grytøyr wrote:
> Jack DeNeut <jdeneut-4GWaZ2qAA/nQT0dZR+AlfA@public.gmane.org> wrote:
>
>> I was wondering if there was any way to set the
''Return-Path'' of an
>> email when using ActionMailer.
>
> I believe this is an MTA configuration issue. If you send the mail
> by SMTP, the MTA typically sets the Return-Path header to be the
> same as the envelope sender. Afaik, there is no way around this
> without changing the MTA configuration. Talk to your sysadmin.
>
> If you send it with sendmail, some systems allow you to specify
> the sender address with the -f option, but this normally means that
> the user running the process that sends the mail must be a trusted
> user. But I don''t even know if there is a way to specidy the -f
option
> with ActionMailer.
It''s not an MTA configuration issue. Actually, it''s even
easier to set
Return-Path when you''re sending with SMTP, because Return-Path is 
simply the envelope sender address. Consider:

[guan@guanmac guan]$ telnet unicast.org 25
Trying 213.150.32.36...
Connected to unicast.org.
Escape character is ''^]''.
220 charon.unicast.org ESMTP
ehlo localhost
250-charon.unicast.org
250-AUTH LOGIN CRAM-MD5 PLAIN
250-AUTH=LOGIN CRAM-MD5 PLAIN
250-PIPELINING
250 8BITMIME
mail from:<fake-return-path-Tn7NQuJrROJAfugRpC6u6w@public.gmane.org>
250 ok
rcpt to:<guan-Tn7NQuJrROJAfugRpC6u6w@public.gmane.org>
250 ok
data
354 go ahead
From: real-return-path-Tn7NQuJrROJAfugRpC6u6w@public.gmane.org
To: guan-Tn7NQuJrROJAfugRpC6u6w@public.gmane.org
Subject: I''m faking it!

.
250 ok 1110359482 qp 1884
quit
221 charon.unicast.org
Connection closed by foreign host.

The address that I''ve entered in the mail from line, 
fake-return-path-Tn7NQuJrROJAfugRpC6u6w@public.gmane.org, is known as the
envelope sender in the
SMTP world, and shows up as return-path when I receive the message.

Of course, I don''t actually know how to set it using ActionMailer ;-)

Guan

Guan Yang <guan-Tn7NQuJrROJAfugRpC6u6w@public.gmane.org> wrote:
> It''s not an MTA configuration issue. Actually, it''s even
easier to set
> Return-Path when you''re sending with SMTP, because Return-Path is
> simply the envelope sender address. Consider:
I may have misread OP, but I got the impression that he needed to 
set the Return-Path to something different from the envelope sender
address. In that case, you''d need to configure the MTA to _not_ set
the Return-Path to the same as the envelope sender address.

-- 
Regards,
Stian Grytøyr

Stian Grytøyr <sgrytoyr-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> I may have misread OP, but I got the impression that he needed to
> set the Return-Path to something different from the envelope sender
> address. In that case, you''d need to configure the MTA to _not_
set
> the Return-Path to the same as the envelope sender address.
I need to correct myself here. It is not possible to have a Return-Path
that is different from the envelope sender address, no matter how much
you configure the local MTA. At least that''s my conclusion after
discussing
this with Guan off-list.

SPF uses the envelope sender address to determine whether or not
the mail should pass. The Return-Path header is then added by the 
last MTA. My tests seem to confirm this. There is no Return-Path in 
the headers as the mail goes over the network from the originating MTA 
to the recipient''s MTA.

-- 
Regards,
Stian Grytøyr

Stian Grytøyr wrote:
>SPF uses the envelope sender address to determine whether or not
>the mail should pass. The Return-Path header is then added by the 
>last MTA. My tests seem to confirm this. There is no Return-Path in 
>the headers as the mail goes over the network from the originating MTA 
>to the recipient''s MTA.
>
>  
>
the Return-Path header is a qmail-specific header. The last (qmail) MTA 
sets it to the envelope address it got when receiving the mail via SMTP. 
Sendmail does the same thing, but writes a "From a@b.com" (without a 
colon) in the first line of the mbox. When using SMTP you can set the 
envelope from address to whatever you want as was shown earlier in this 
thread.

Sebastian

On Wed, 9 Mar 2005 08:37:59 +0100, Jack DeNeut
<jdeneut-4GWaZ2qAA/nQT0dZR+AlfA@public.gmane.org>
wrote:
> I was wondering if there was any way to set the
''Return-Path'' of an
> email when using ActionMailer.  Without the ability to set the
> ''Return-Path'' of an email, it is impossible to avoid
being labeled as
> ''spam'' by many SMTP gateways if trying to send mail on
another''s
> behalf.  SPF doesn''t care about the ''from'' line
in an email, only the
> ''Return-Path''.
It strikes me that what you''re trying to do is the *reason* SPF was
created.  If it were easy for any old person to set the relevant
headers SPF would be .... useless.

Have I missed something?
> Why would I want to do that?  Because I am working as a consultant for
> another company, and when responding to bug reports I want to make
> things easier for the users by replying ''from'' the
client''s domain.
> Unfortunately, they can''t give me access to their SMTP server
(they''re
> afraid to muck with sendmail and so I get ''can not relay''
when I use
> their SMTP gateway).
> 
> For example, here are the headers from a mail I sent to myself using
> ActionMailer.  As you can see, Gmail has marked it as
''fail'' (in
> ''Received-SPF'') :
> 
> X-Gmail-Received: aac7ac60620782da0f1e605962a47ceaf022a2d0
> Delivered-To: jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
> Received: by 10.38.12.43 with SMTP id 43cs8575rnl;
>          Tue, 8 Mar 2005 22:51:57 -0800 (PST)
> Received: by 10.38.82.76 with SMTP id f76mr547559rnb;
>          Tue, 08 Mar 2005 22:51:57 -0800 (PST)
> Return-Path: <do-not-reply-5tc4TXWwyLM@public.gmane.org>
> Received: from omta16.mta.everyone.net (sitemail2.everyone.net
> [216.200.145.36])
>          by mx.gmail.com with ESMTP id 71si394734rna.2005.03.08.22.51.56;
>          Tue, 08 Mar 2005 22:51:56 -0800 (PST)
> Received-SPF: fail (gmail.com: domain of
do-not-reply-5tc4TXWwyLM@public.gmane.org does not
> designate 216.200.145.36 as permitted sender)
> Received: from pmta01.mta.everyone.net (bigiplb-dsnat [172.16.0.19])
>         by omta16.mta.everyone.net (Postfix) with ESMTP id 301233FDA8
>         for <jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>; Tue, 
8 Mar 2005 22:51:55 -0800 (PST)
> X-Eon-Sig: AQIdLpBCLp0L6UAQSwIAAAAB,99b3d5966c8c0368c842a831fa4ddfdd
> Received: from smtp.everyone.net (62.245.95.172 [62.245.95.172])
>         by pmta01.mta.everyone.net (EON-AUTHRELAY) with ESMTP id 24AB116D
>         for <jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>; Tue, 8
Mar 2005 22:51:55 -0800
> Date: Wed, 9 Mar 2005 07:51:53 +0100
> From: do-not-reply-5tc4TXWwyLM@public.gmane.org
> To: jdeneut-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
> Subject: =Thank you for your bug report
> Content-Type: text/plain; charset=utf-8
> Message-Id:
<20050309065155.301233FDA8-CkVda1wFVPjdi7ou1J7GeDGekZJkHWME@public.gmane.org>
> 
> I tried this:
> class MyMailer < ActionMailer::Base
>      def my_mail(recipients, post)
>        @headers["Return-Path"]      =
"jdeneut-4GWaZ2qAA/nQT0dZR+AlfA@public.gmane.org"
>       end
> end
> 
> but it doesn''t work (trying to set the
''Return-Path'' by playing with
> the headers doesn''t work in JavaMail either.  Java has an SMTP
wrapper
> for setting ''Return-Path''). I''ve looked in TMail
as well, but didn''t
> see it there. Is this even supported in Ruby (setting the
> ''Return-Path'')?
> 
>   Regards,
> 
> Jack DeNeut
> 
> _______________________________________________
> Rails mailing list
> Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
> 

-- 
Cheers

Koz

On 9 Mar 2005, at 20:51, Sebastian Kanthak wrote:
> the Return-Path header is a qmail-specific header.
Return-Path is defined in RFC2821 section 4.4. It''s not qmail specific.

Guan

Hi,

Michael Koziarski wrote:
>On Wed, 9 Mar 2005 08:37:59 +0100, Jack DeNeut
<jdeneut-4GWaZ2qAA/nQT0dZR+AlfA@public.gmane.org> wrote:
>  
>
>>I was wondering if there was any way to set the
''Return-Path'' of an
>>email when using ActionMailer.  Without the ability to set the
>>''Return-Path'' of an email, it is impossible to avoid
being labeled as
>>''spam'' by many SMTP gateways if trying to send mail on
another''s
>>behalf.  SPF doesn''t care about the ''from''
line in an email, only the
>>''Return-Path''.
>>    
>>
>
>It strikes me that what you''re trying to do is the *reason* SPF was
>created.  If it were easy for any old person to set the relevant
>headers SPF would be .... useless.
>
>Have I missed something?
>
>  
>
AFAIK, what SPF does, is to check whether the domain of the Return-Path 
address and the IP-address of the last SMTP server that sent the message 
(can be found in the last "Received:" header and can not be
manipulated
as it is added by the receiving mail server) match. "Match" means that
you check a special DNS entry to see, if this IP is authorized to send 
e-mails with the domain used in the Return-Path. So to be SPF-compliant 
you have to set the Return-Path to a domain where you control DNS and 
have a DNS entry that permits your IP to send e-mails with this domain 
in the Return-Path.

So in the scenario described, you are fine, when you set the 
from-address to the value supplied by the user, but the Return-Path 
address to a mailbox in your domain. This means that you''ll get bounces
and that it is clear, who is responsible for the e-mail.

Hope this explanation was mostly correct...

Sebastian