[Mimedefang] HELO filtering (again)

[Jeff Rife]

After the last discussion, I decided to add logging for HELO parameters 
that do not resolve (using a DNS search for 'A' records, like the RFC 
says), but only if the other filtering wouldn't reject it.

Although I only have 13 samples, it's a miserable failure.

Of the thirteen, eleven ended up being blocked by greylisting, and the 
other two were sites that I wanted e-mail from (one was eBay).

If I had not gotten the two false positives, I would have left this 
check in place a while longer.  But, it's gone now, because the time it 
takes to do the DNS call isn't worth it for any kind of check of the 
HELO parameter, at least for me.


--
Jeff Rife | "Women...can't live with 'em...can't explain to  
          |  the desk clerk why you only need one bed." 
          |  
          |         -- Ellen