X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/e05f33e0b79c14608757a60f2f3f8588008355f7..e0f3765aeecd3116bb4171bd0c5f9b609e7c0588:/configs/config.samples/F001?ds=sidebyside diff --git a/configs/config.samples/F001 b/configs/config.samples/F001 new file mode 100644 index 000000000..fd219549f --- /dev/null +++ b/configs/config.samples/F001 @@ -0,0 +1,35 @@ +From: Ephraim Silverberg +Date: Tue, 17 Feb 1998 12:55:55 +0200 + +We're using Exim 1.82 and have written a message filter to intercept spam +messages that RBL doesn't catch. Since we have met with reasonable success +since installing (and refining) the filter -- 566 genuine spam messages +intercepted during a time period where there were 67 RBL rejections -- I +thought that the rest of the list may be interested in reviewing our filter +as a starting point for their own system message filter. + +There are a number of caveats, however: + +1. The suspected spam is not automatically rejected as RBL hosts are, but + is saved to a folder that should be read/writable by the mail + administrators. The reason for this is that the filter catches also + some legitimate mail and these messages should be bounced to their + originally intended recipient(s) (ala X-Envelope-To:) and the filter + refined and/or the databases (described below) updated. + +2. My filter traps blank/non-existent To: lines as well as To: lines + contained in From: lines, but firsts exempts the following categories + from this check: mailing lists, local mail, mail originating in the + country (e.g. in our case *.il) and mail coming from autosupport servers. + +Beyond implicit checks, it uses four DBM databases: two that exempt the +message from any spam (beyond RBL) checks (software servers and strange mailing +lists need to be here) -- one based on $sender_address and the other on +$header_to: lines -- and, conversely, two databases for known spammers that +have valid mail headers that aren't caught by implicit checks. All entries +in these databases are lowercase so that we don't need two lines for +'friend@public.com' and 'Friend@Public.com'. + +The sample filter package is at ftp://ftp.cs.huji.ac.il/pub/exim/spam_filter/ + +Comments and suggestions are welcome.