- "Sam" <[EMAIL PROTECTED]>:
| On Mon, 8 Mar 1999, Jason Haar wrote:
|
| > I know there's a bunch of patches out the to make Qmail do this, but I was
| > wondering if anyone had done it in a similar fashion to rblsmtpd - i.e. it
| > would do the check and then pass the connection onto the next part of the
| > chain - rblsmtpd, qmail-smtpd, whatever.
|
| How would you propose going about writing clairvoyant code which would
| know in advance that the client on the other side of a new SMTP connection
| will do a MAIL FROM: with an unresolvable address at some point in the
| future?
Clearly, you can't. But what you could do is to have a program
sitting between the TCP socket and qmail-smtpd. Normally, it would
just pass every incoming command to qmail-smtpd, but it would check
any MAIL command first. If it's bad, it will take over and reject
every RCPT or DATA command until a RSET or new MAIL command appears.
I am not saying this is a good idea, only that it could be done.
Since the front end has to parse the entire SMTP protocol in order to
avoid responding to data in the body of a message, it would be a lot
easier to simply run a patched qmail-smtpd.
Avoiding patches is a valid goal, but not at any price.
- Harald
