On Thu 24/Jan/2013 02:00:15 +0100 Sam Varshavchik wrote: > Alessandro Vesely writes: > >> -allow=zone[,varspec]... >> >> [...] >> Now for passing the results to global filters. In 2010 we thought of > > I still think -allow is ok, but I don't see much need to do anything > with regards to the headers. If the purpose is to allow per-recipient > mail filtering, then environment variables set by couriertcpd should > be accessible in rcptfilter and smtpfilter-based scripts for that > purpose, and it's better to do it there.
Global filters, however, cannot. My initial idea was to use ctlfile records to pass values to --and possibly among-- filters. It's you who said it's simpler to use the message header (there were traces of that argument quoted in my previous message.) An advantage, in large systems, is that it makes it possible to pass values from a boundary MTA to an internal MTA. In addition, using a standardized header would allow independently developed filters, e.g. SA, to reuse that result rather than querying the list again on their own. Oh, I forgot to mention to add, say, "opt BOFHARGUARDATOMS=2". That is the number of rightmost "atoms" to be kept from config-me: The lower the safer. For example, if me is host.example.com, 2 yields example.com, and an A-R header purportedly by whatever.example.com gets renamed. That's a possible implementation of RFC 5451. > And I'd rather keep it simple, and avoid the need to bring in PCRE. > I'm not even quite sure why that's necessary. A DNSBL that offers > multiple results should do it by returning pseudo-IP addresses, which > couriertcpd should be able to handle. Yes, that was my initial approach as well. Lists deliver their content as A records in the 127.0.0.0/8 range, but each list has its own encoding. Dnswl.org, for example, encodes the score is the last byte, valued 0-3. After a few attempts at defining a suitable syntax, I realized I was reinventing regular expressions, so I turned to the real thing. Some decisions, e.g. SPFALLOW, ought to be made that early. Would PCRE unduly aggravate tcpd's footprint? And how'd you compare its cpu cost to the time/bandwidth cost of the query itself? ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnnow-d2d _______________________________________________ courier-users mailing list courier-users@lists.sourceforge.net Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
