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Subject: RE: Some questions on postfix, SUMMARY
From: Karimov, Rashid (NBC, CNBC) (Rashid.Karimovnbc.com)
Date: Fri Mar 03 2000 - 08:46:02 CST

Folx,
(below)
>
> > C. Is modification of B, when instead of directly
> using the same
> > routines as sendmail uses, one just fork()s and exec*()
> sendmail
> > program to drop the message into the maildrop.
> >
> > Possible problems with that:
> >
> > 1. On a slow system, fork()/exec() pair will be slow :)
>
> Have you tried this? Unless you run a dog of an operating system
> you should be able to fork/exec a hundred or more times a second.
> That's more than enough, given that it takes much more time to
> write mail to disk.
>
> There is the other variant, and that is to take a few Postfix
> routines and write a sendmail-like program that injects directly
> into the queue. However, that program would have to run set-uid
> postfix, which is OK only in a tightly-controlled environment.
>
> If that is an option to consider, then I could write such a beast.
> But it would be an optional thing, not recommended for general use.

Wietse,

I think there is definitely a demand for a thing like this, may be
even just a fast routine (thread-safe would be great) one can call:

maildrop_it(** recepients, *message_buffer)

that one can use in a custom message generation program. If it is
a cross-platform (WinNT), it would be a real killer .

Some of our messages are generated on WinNT (don't ask me why ! :),
and if an NT system can just drop off a message into NFS-mounted maildrop
queue, it would ease the transition.

I understand a danger of something like that on a general use system (.edu),
or when used by spammers, but there is a large number of legitimate
business (like ours :) that need this __badly__.

In our case, subs subscribe to be notified about various async (market
driven) events,and when these happen, we must notify them in a hurry.
Some messages are the same, but majority are unique for different users.

And we are talking about lots of these messages - up to 1 Mil per event (!).

Wietse,

- you mention in the docs, that there is very little chance that an
arbitrary
message dropped into maildrop can be considered a valid postfix message -
how
is it protected ? Is there a signature of some kind that only is generated
when
postfix's sendmail is properly called ? Is it the mail_stream_file() that
generates the signature ?

I would like to help you (and the community) with writing this routine (see
above),
and any input from the author or people-in-the-know would be appreciated.

Rashid.
 

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