dovecot - Feb 2023 - Pigeonhole Sieve Vacation Reply-To peculiarity with inbound AWS-SES

> Am 08.02.2023 um 08:37 schrieb Stephan Bosch <stephan at
rename-it.nl>:
> 
>
https://doc.dovecot.org/settings/pigeonhole-ext/vacation/#pigeonhole_setting-sieve_vacation_send_from_recipient
> 
> On 7-2-2023 15:01, Dr. Rolf Jansen wrote:
>> To begin with, usage of Amazons Simple Email Service (SES) is mandatory
for outgoing mails from AWS-EC2 instances. The Pro is, it does work and we may
utilize email relays with high reputation for our outgoing mails at no
additional costs. The Con's are that (A) SES does not relay mails with empty
<> MAIL FROM addresses and (B) it fiddles with the envelope addresses of
the relayed mails.
>> 
>> Anyway this is out of our control, and while I could avoid (A) by
switching the e-mail service provider, I still have no control over (B) because
this affects replying to emails from others using AWS-SES.
>> 
>> Problem A) The empty-MAIL-FROM may be effectively addressed by setting
Pigeonhole?s sieve_vacation_send_from_recipient to ?yes?.
Yes that?s important for resolving problem A, and I wrote this already (s.
above).

Without my patch, problem B remains unresolved, though.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: pigeonhole-vacation-sender-fix.patch
Type: application/octet-stream
Size: 597 bytes
Desc: not available
URL:
<https://dovecot.org/pipermail/dovecot/attachments/20230208/3c9f0628/attachment.obj>

On 8-2-2023 13:10, Dr. Rolf Jansen wrote:
>> Am 08.02.2023 um 08:37 schrieb Stephan Bosch <stephan at
rename-it.nl>:
>>
>>
https://doc.dovecot.org/settings/pigeonhole-ext/vacation/#pigeonhole_setting-sieve_vacation_send_from_recipient
>>
>> On 7-2-2023 15:01, Dr. Rolf Jansen wrote:
>>> To begin with, usage of Amazons Simple Email Service (SES) is
mandatory for outgoing mails from AWS-EC2 instances. The Pro is, it does work
and we may utilize email relays with high reputation for our outgoing mails at
no additional costs. The Con's are that (A) SES does not relay mails with
empty <> MAIL FROM addresses and (B) it fiddles with the envelope
addresses of the relayed mails.
>>>
>>> Anyway this is out of our control, and while I could avoid (A) by
switching the e-mail service provider, I still have no control over (B) because
this affects replying to emails from others using AWS-SES.
>>>
>>> Problem A) The empty-MAIL-FROM may be effectively addressed by
setting Pigeonhole?s sieve_vacation_send_from_recipient to ?yes?.
> Yes that?s important for resolving problem A, and I wrote this already (s.
above).
>
> Without my patch, problem B remains unresolved, though.
Oh, right..let's say it's early here.
Your patch seems a bit risky though. It will try to send replies to whatever is
in sender, resent-from, or from header (whichever is found first in that order),
without considering where it might have actually come from. Just hoping that MTA
in between checks whether headers match the envelope, before it is mangled by
AWS.

 ?Regards,

Stephan.