Bouncing messages in mod_smtpd

[Rian Hunter <ri...@MIT.EDU>]

Hey!

January has brought in some great improvements to mod_smtpd. If you  
compare the code now to the code six months ago you'll see that it is  
very clean and very workable now, not that it wasn't before it's just  
that now some distinctions have been made that makes thinking about  
extending mod_smtpd a lot easier. I expect plugin writers to bring up  
some points where mod_smtpd will have to be extended, and those  
extensions will happen when the time is right.

Anyway, I'm facing one issue. When an SMTP envelope has more than one  
recipient and the queue plugins are only able to queue some of them  
mod_smtpd has the responsibility to bounce the unqueued messages back  
to the sender. Of course in a proper set up this shouldn't happen  
because mod_smtpd won't give a "250 Ok" response to the "RCPT"  
command if it doesn't support the recipient, but there might be cases  
where a plugin is unable to queue for other unexpected reasons.

mod_smtpd needs a bouncing mechanism! I need some help with this  
because I am not sure how to approach this. Should I implement an  
entire SMTP client in mod_smtpd to bounce messages? Should I relegate  
this responsibility to a sendmail command or what platform specific  
mailer there is? Are there other options?

I want to dedicate the rest of this week to writing some drafts of  
documentation and a website for mod_smtpd, so if someone would like  
to volunteer to mess with bouncing that would be a great help! The  
code to look at is in
http://svn.apache.org/repos/asf/httpd/mod_smtpd/trunk/src/ 
smtp_protocol.c, the function is smtpd_bounce_unqueued 
(smtpd_session_rec *). Thanks!!

Rian Hunter

Re: Bouncing messages in mod_smtpd

[Rian Hunter <ri...@MIT.EDU>]

On Feb 1, 2006, at 7:51 PM, Garrett Rooney wrote:
> Well, we already have a small SMTP implementation in the SMTP queue
> module, that could be made somewhat more generic and used for this
> sort of thing.

Yeah I was thinking about that! I'm just so fearful of code-bloat and  
possibly maintaining an SMTP client but I may just end up doing that.

Rian Hunter

Re: Bouncing messages in mod_smtpd

[Garrett Rooney <ro...@electricjellyfish.net>]

On 2/1/06, Rian Hunter <ri...@mit.edu> wrote:

> mod_smtpd needs a bouncing mechanism! I need some help with this
> because I am not sure how to approach this. Should I implement an
> entire SMTP client in mod_smtpd to bounce messages? Should I relegate
> this responsibility to a sendmail command or what platform specific
> mailer there is? Are there other options?

Well, we already have a small SMTP implementation in the SMTP queue
module, that could be made somewhat more generic and used for this
sort of thing.

> I want to dedicate the rest of this week to writing some drafts of
> documentation and a website for mod_smtpd,

Yay!

-garrett