Re: zmailer filter function

[Matti Aarnio <mea@nic.funet.fi>]

> Just wondering if you saw my note in the zmailer mailing list. Would such
> a thing be possible? You could filter the entire contents of the
> message to an external process. The process would expect the message to
> arrive via stdin, and then it could pipe out the new message via stdout,
> which zmailer would read from, for the new message to work with.
> I'm sure alot of people would be able to use this. Here is the message
> that I sent to the list:

	Yes, I saw it, and have been thinking about it.
	... though I only envisioned getting filtered headers
	and some addressing information back.

	The thing I am "a bit" shy about, is the usage of separate
	(external) process to do the filtering.

> I know about the intercept function in crossbar.cf with it's drop, file
> and error "functions".. but would it be possible to add a filter function
> to zmailer??
> Basically I need to be able to 'rewrite' ANY incoming/outgoing headers and
> possibly scan a message for specific contents (ie uuencoded/mime
> attachments and decode them and test for a virus).. what I am thinking is the
> following:
> 
> .... basically what I described above ..
> 
> You should be able to get the idea of what I am trying to do. Can this be
> done? It would add ALOT of functionality to zmailer. Which is already a great
> system.

	If the plan is to allow integration of some sort of LISTSERV
	into the mailer proper -- well, I am not entirely appealed to
	an idea of letting the ROUTER run such thing.
	(It would require forking for each message, reading things,
	 and outputting proper data back..)

	On the other hand...  If such module does basic header rewriting,
	(scrubs away some, edits others), and returns the new set to the
	router along with addresses, it could be used to implemend a
	moderated lists -- and as ubiquitously insertable censor function..

	I must say, I am somewhat uncertain if it would be Good Idea
	at all...

> --
>  Name:Trevor Paquette      |Alberta Energy Company Ltd |Work:(403) 266-8400
> Email:TrevorPaquette@aec.ca|3900, 421 7th Ave S.W.     | Fax:(403) 290-8400
>       postmaster@aec.ca    |Calgary, Alberta, Canada   |ICBM:51'05"N/114'01"W
>       root@aec.ca          |T2P 4K9                    |Mind:In the Rockies..

	/Matti Aarnio <mea@nic.funet.fi>