-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Josh Grebe wrote: > Hello, > > I have been comtemplating writing a pre-DATA hook into courier to allow for more > efficient greylisting. I guess it would actually hook into the RCPT TO: handler. > The biggest problem with the current method (in my opinion) is that it runs so > late in the process, after having already recieved the message. It also uses > hashes of the entire message, which seems to me to be a level of paranoia that > will cause more problems than solve. > > If each successful message stores remote address, sender email, and recipient > email, a "2 out of 3" test seems pretty reasonable to me. > > Has anyone seen a situation where the MAIL FROM: changes on a retry? I'm > thinking of things like mailing lists that automagically handle bounces, things > like that. > > I'm interested in any comments or criticism. > > Josh > > Sander Holthaus wrote: >> Dino Ciuffetti wrote: >> >>>>>> http://www.freenux.org/~mm/wordpress/?p=6 >>>>>> http://swik.net/courier-pythonfilter >>>> I'm testing greylist.py pythonfilter module for courier-mta. I >>>> wrote a little consideration about it. You'll find at >>>> http://www.freenux.org/~mm/wordpress/?p=6 >>>> >>>> Ciao, Dino. >>>> >>>> >>>> >>>> >>>> ------------------------------------------------------- This SF.Net >>>> email is sponsored by xPML, a groundbreaking scripting language >>>> that extends applications into web and mobile media. Attend the >>>> live webcast and join the prime developer group breaking into this >>>> new coding territory! >>>> http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 >>>> _______________________________________________ courier-users >>>> mailing list [email protected] Unsubscribe: >>>> https://lists.sourceforge.net/lists/listinfo/courier-users >>>> >> I'm interested in seeing the changes you made. As I recall, I had >> several reasons not to implement greylisting/comeback-again as it was >> and lacked the time (and Python knowledge) to hack it myself. >> I would still like to see Greylisting in the default codebase of >> Courier, as it is a very potent anti-spam/phising/virus sollution. >> >> Kind Regards, >> Sander Holthaus > That is an interesting idea. A pre-DATA filter would indeed allow much more efficient greylisting as well as doing call-backs before acceptence. As for the md-5 hashes, I'm not sure about those. They can cause some extra problems, but you could solve those by using a fuzzy signature such as Nilsimsa. You can also just hash the message-body, which should always stay the same (?).
I'm not sure if MAIL FROM's get changed on 4xx's. My guess would be, no, otherwise I can't understand why greylisting is used so widely. Kind Regards, Sander Holthaus -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.2 (MingW32) iD8DBQFEMxc8Vf373DysOTURAiBVAJ9ALe48eBmSvufQw+UGpozaxsQrvgCgyar+ gfoy4Ww3xdn5XPVuI4P0Yyo= =8KVD -----END PGP SIGNATURE----- ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ courier-users mailing list [email protected] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
