Thanks much Brian, for your input. Actually the intent is not to identify spam per se... the system I'm building already has a pretty tight anti-spam in that messages are only accepted if the recipient has previously authorized the sender (e.g. senders are present in the recipient's addressbook).
However, I can't simply rule out everything because DSNs and other potential messages from postmaster@ or mailer-daemon@ need to get through as well. So I was building a mailfilter rule which allows messages like that to go through safely. But I did want to do my best at trying to "validate" the DSNs... meaning, if a message with an empty sender "<>" comes in, is this likely a legitimate DSN type message, or does it look like junk? So what I ended up with was to only accept empty sender messages that are of the type multipart/report, and deny all others. I'm just wondering if the "deny all others" (with empty sender) will present a problem. Ricardo On Tue, 4 Mar 2003 23:19:18 +0000 Brian Candler wrote: > On Tue, Mar 04, 2003 at 06:26:59AM -0800, [EMAIL PROTECTED] wrote: > > You mean Qmail does not produce a multipart/report message? The empty > > sender is ok, what I'm trying to do is match up an empty sender with a > > multipart/report message. > > > > If Qmail doesn't provide multipart/report, then I guess I'm making the > > wrong assumption. > > > > Is that the case? If so, can someone point me to documentation of how > > Qmail formats its bounces? > > It sounds to me like you may be looking for the wrong solution. > > The underlying problem you are trying to solve, if I understand correctly, > is to reduce the amount of spam which is delivered into your mailbox. > If so, > identifying mail with <> empty envelope sender but not a bounce is > going to > make hardly any impact. Most spam is sent with forged sender > addresses. So I > think your efforts in this area will be wasted, and in any case, if > you can > identify bounces which qmail generates, you won't be able to identify > bounces from xyz-random-mailer which is also in use on the Internet. > > Tools which you may find useful in reducing spam include: > http://www.spamassassin.org/ > http://tmda.net/ > http://www.paulgraham.com/antispam.html > http://www.paulgraham.com/filters.html > > Regards, > > Brian.
