dovecot - Aug 2008 - dovecot sieve sends vacation messages with null envelope sender

I am using this simple sieve script to do "vacation":

require ["fileinto", "vacation"];
if exists "X-Spam-Flag" {
  stop;
}
vacation
  :days 1
  :subject "Out of office reply"
  :addresses ["<email address hidden>", "<email address
hidden>" ]
"I am on vacation until 2008-08-07.
If you have something urgent, please contact: Jan Novak <email address 
hidden>
";

I use sql lookups for users and passwords. For some reason the default 
location ~/.dovecot-sieve did not work for some reason. However I prefer 
to put sieve scripts to /var/lib/sieve and when I added additional field 
to lookup with this location it started to work.

But it sends vacation messages with null envelope sender, which is in my 
opinion undesirable, because many vacation messages are caught in spam 
filters.

I think there could be same sender on envelope.
In dovecot-sieve/src/sieve-cmu.c around line 380 is a call to 
smtp_client_open(src->addr, NULL, &f);
NULL could be replaced with src->fromaddr

Maybe some more patching may be necesary. I found similar patch for 
cyrus-imapd at
http://oss.digirati.com.br/mail/cyrus.html 
<http://oss.digirati.com.br/mail/cyrus.html>

My current system:
1)  Ubuntu 8.04.1

jl at mail:~$ dovecot --version
1.0.15

It is a backported package from ubuntu intrepid ibex. However the same 
applies for dovecot 1.0.10 which is in ubuntu 8.04.


Summary:
I expect messages sent by vacation recipe should have envelope from same 
as user's e-mail address. This is then writen to Return-Path: header by 
receiving MTA

NULL envelope from is used, resulting (in my case) to Return-Path: <> 
rewriten by postfix to Return-Path: <MAILER-DAEMON> by receiving MTA

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Am 12.08.2008 13:32 schrieb Josef Li?ka:
> 
> ?
> But it sends vacation messages with null envelope sender, which is in my 
> opinion undesirable, because many vacation messages are caught in spam 
> filters.
> 
> I think there could be same sender on envelope.
> In dovecot-sieve/src/sieve-cmu.c around line 380 is a call to 
> smtp_client_open(src->addr, NULL, &f);
> NULL could be replaced with src->fromaddr
Hi Josef,

this is not a bug - it's a _fetaure_ :-)
This morning Stephan Bosch wrote:
http://www.dovecot.org/list/dovecot/2008-August/032799.html


Regards,
Pascal

Josef Li?ka schreef:
> But it sends vacation messages with null envelope sender, which is in 
> my opinion undesirable, because many vacation messages are caught in 
> spam filters.
>
> I think there could be same sender on envelope.
> In dovecot-sieve/src/sieve-cmu.c around line 380 is a call to 
> smtp_client_open(src->addr, NULL, &f);
> NULL could be replaced with src->fromaddr
>
> [...]
>
> Summary:
> I expect messages sent by vacation recipe should have envelope from 
> same as user's e-mail address. This is then writen to Return-Path: 
> header by receiving MTA
>
> NULL envelope from is used, resulting (in my case) to Return-Path: <>
> rewriten by postfix to Return-Path: <MAILER-DAEMON> by receiving MTA
Interesting. I've seen a very similar suggestion yesterday. However, as 
I explained in the previous post, the use of a non-null envelope from 
field is discouraged by the Sieve vacation RFC (5230) and also by a more 
generic RFC (3834) describing the do's and dont's regarding
auto-responders:

http://www.dovecot.org/list/dovecot/2008-August/032799.html

It puzzles me why spam filters would reject messages with a <> return 
path, which is a very common an valid use of the SMTP protocol. What 
spam filter are we talking about anyway?

Regards,

Stephan.

On 8/12/2008, Josef Liaka (jl at chl.cz) wrote:
> But it sends vacation messages with null envelope sender, which is in
> my opinion undesirable,
It is not only desirable, as Stephan already pointed out to someone 
else, it is per the spec:

"This behavior is implemented as such on purpose. From RFC5230 
(http://www.ietf.org/rfc/rfc5230.txt):

5.1.  SMTP MAIL FROM Address

    The SMTP MAIL FROM address of the message envelope SHOULD be set to
    <>.  [...]"

 >  because many vacation messages are caught in spam filters.

So what? Many people consider them spam already.

Please don't muck with things like this unless you have a really, really 
good reason...

-- 

Best regards,

Charles

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Hash: SHA1

Josef,
   This is exactly same situation in our environment as well. I had to
make the same change as you stated.  Our central virus/spam email
gateway also cans any message with out a valid from address in the mail
headers.  I would think most virus/spam systems will do the same.
   I understand the concept of having the from empty, namely to keep
another automated system from replying back to your vacation reply, but
what do we do to keep our vacation replies being canned by anti-spam
systems??  Maybe this should be a option in the configuration file to
let the Admin decide whether to fill in the from address field, or a
"donot-reply at domain.com" default, or just empty?


Josef Li?ka wrote:
> I am using this simple sieve script to do "vacation":
> 
> require ["fileinto", "vacation"];
> if exists "X-Spam-Flag" {
>  stop;
> }
> vacation
>  :days 1
>  :subject "Out of office reply"
>  :addresses ["<email address hidden>", "<email
address hidden>" ]
> "I am on vacation until 2008-08-07.
> If you have something urgent, please contact: Jan Novak <email address
> hidden>
> ";
> 
> I use sql lookups for users and passwords. For some reason the default
> location ~/.dovecot-sieve did not work for some reason. However I prefer
> to put sieve scripts to /var/lib/sieve and when I added additional field
> to lookup with this location it started to work.
> 
> But it sends vacation messages with null envelope sender, which is in my
> opinion undesirable, because many vacation messages are caught in spam
> filters.
> 
> I think there could be same sender on envelope.
> In dovecot-sieve/src/sieve-cmu.c around line 380 is a call to
> smtp_client_open(src->addr, NULL, &f);
> NULL could be replaced with src->fromaddr
> 
> Maybe some more patching may be necesary. I found similar patch for
> cyrus-imapd at
> http://oss.digirati.com.br/mail/cyrus.html
> <http://oss.digirati.com.br/mail/cyrus.html>
> 
> My current system:
> 1)  Ubuntu 8.04.1
> 
> jl at mail:~$ dovecot --version
> 1.0.15
> 
> It is a backported package from ubuntu intrepid ibex. However the same
> applies for dovecot 1.0.10 which is in ubuntu 8.04.
> 
> 
> Summary:
> I expect messages sent by vacation recipe should have envelope from same
> as user's e-mail address. This is then writen to Return-Path: header by
> receiving MTA
> 
> NULL envelope from is used, resulting (in my case) to Return-Path: <>
> rewriten by postfix to Return-Path: <MAILER-DAEMON> by receiving MTA
> 
- --
C. J. Keist                     Email: cj.keist at colostate.edu
UNIX/Network Manager            Phone: 970-491-0630
Engineering Network Services    Fax:   970-491-5569
College of Engineering, CSU
Ft. Collins, CO 80523-1301

All I want is a chance to prove 'Money can't buy happiness'
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