I see no documents in the Dovecot documents wiki on how Dovecot features can be used in the fight against spam. One hit came up in a search, and it was about how to fight spam in the MoinMoin Wiki itself (e.g. TextCHAs and such). I already asked in another thread about removing message files at the search from a designated "learn-spam" folder. My next question would be how to automatically place detected spam into a specific folder for the user to access or ignore as they deem fit. That would seem to me to be something for the deliver command and its -m option. But this might be more of a Dovecot and MTA coordination issue, too (e.g. how to get the spam detection done in the MTA ... Postfix in my case ... to become a label of some sort that ends deciding the folder. The -m option might be harder to get it dynamically set since it would be hard coded in master.cf for Postfix (so a variable has to be able to direct it to INBOX in this case). But maybe the "standard" way of doing this is to shim another program between the MTA (Postfix for me) and the LDA (Dovecot deliver) to dynamically add the -m option on the fly? Lacking any other clever solution, this seems to me to be the way I could make it work. Maybe there is a special header deliver could detect, such as "X-Spam: yes"? A wiki document on how Dovecot helps (or how to help Dovecot) in the fight against spam, I think, would be helpful.
On Tue, 1 Jun 2010 09:42:18 -0400 Phil Howard wrote:> I see no documents in the Dovecot documents wiki on how Dovecot > features can be used in the fight against spam. One hit came up in a > search, and it was about how to fight spam in the MoinMoin Wiki itself > (e.g. TextCHAs and such).Fighting against SPAM is the MTA's job. Dovecot's job is to provide access to the mailboxes for the users. --Frank Elsner
On Tue, 1 Jun 2010 09:42:18 -0400 Phil Howard <ttiphil at gmail.com> articulated:> I see no documents in the Dovecot documents wiki on how Dovecot > features can be used in the fight against spam. One hit came up in a > search, and it was about how to fight spam in the MoinMoin Wiki itself > (e.g. TextCHAs and such)The fight against SPAM is NOT Dovecots responsibility. There are numerous applications that work with your MTA for that purpose. I suggest that you investigate this further. You might want to start here: http://www.ijs.si/software/amavisd/ They also have their own mailing list that you can use to answer any questions that you might have. -- Jerry Dovecot.user at seibercom.net Disclaimer: off-list followups get on-list replies or get ignored. Please do not ignore the Reply-To header. __________________________________________________________________
On 2010-06-01 9:42 AM, Phil Howard wrote:> I see no documents in the Dovecot documents wiki on how Dovecot > features can be used in the fight against spam. One hit came up in a > search, and it was about how to fight spam in the MoinMoin Wiki itself > (e.g. TextCHAs and such).1. Set up postfix (or whatever MTA you are using) to reject as much as possible at SMTP time. If done right postfix can reject 90+% (depending on how much /what type of spam your domains get) with pretty much zero FPs... Lots of examples down in the UCE/Virus section here: http://www.postfix.org/docs.html 2. Add amavisd-new+spamassassin to the mix, and tag+deliver anything it detects as spam into the junk folder using sieve... http://wiki.dovecot.org/LDA/Sieve#SpamAssassin_tagged_mail_filtering There is also a plugin for dovecot that makes it easy for users to reclassify stuff as spam or not spam by simply moving the messages to the appropriate folder, but I think it is mainly designed for DSPAM... anyone using it with spamassassin? -- Best regards, Charles
On 2010-06-01 10:34 AM, Charles Marcus wrote:> There is also a plugin for dovecot that makes it easy for users to > reclassify stuff as spam or not spam by simply moving the messages to > the appropriate folder, but I think it is mainly designed for DSPAM... > anyone using it with spamassassin?Sorry, meant to include a link: http://johannes.sipsolutions.net/Projects/dovecot-antispam -- Best regards, Charles
On Tuesday 01 June 2010 15:42:18 Phil Howard wrote:> I see no documents in the Dovecot documents wiki on how Dovecot > features can be used in the fight against spam. One hit came up in a > search, and it was about how to fight spam in the MoinMoin Wiki itself > (e.g. TextCHAs and such).I guess you'll have the mental transfer of "fight spam" into "cause dovecot to perform this and that action" yourself. The possible actions are, in general, documented.> I already asked in another thread about removing message files at the > search from a designated "learn-spam" folder. My next question would > be how to automatically place detected spam into a specific folder for > the user to access or ignore as they deem fit.You need to configure the MTA to accept and tag spam messages, e.g. with Amavis D_PASS policy and appropriate tag levels. Then the most flexible way to put the mails into a spam folder is to use the deliver plugin for sieve, which can sort and filter mails depending on many different conditions, like presence and/or value of any header. You can deploy a single system wide default script for all users, which can be complemented or overwritten by individual users (depending on configuration). See http://wiki.dovecot.org/LDA/Sieve If you use dovecot 1.2, using the new Dovecot Sieve plugin is highly recommended above the old CMUsieve. See http://wiki.dovecot.org/LDA/Sieve/Dovecot The really recommended way nowadays is different though: *reject* as much spam as possible in the MTA in the receiving SMTP dialog, with a combination of blacklists, sender validation (e.g.DKIM), potentially greylisting (as you deem appropriate) and lastly content scanning with s.th. like amavis+spamassassin. I'd not expect a noticable amount of false positives, and in the rare cases the sender will be notified. The false positives rate of users scanning through a folder of tagged mail will be higher.> A wiki document on how Dovecot helps (or how to help Dovecot) in the > fight against spam, I think, would be helpful.A howto-like page to describe the usage of some dovecot features in an anti- spam context wouldn't hurt, OTOH there is not much anti-spam specific stuff at all at the dovecot side. Rainer
On 01/06/2010 14:42, Phil Howard wrote:> I see no documents in the Dovecot documents wiki on how Dovecot > features can be used in the fight against spam. One hit came up in a > search, and it was about how to fight spam in the MoinMoin Wiki itself > (e.g. TextCHAs and such). > > I already asked in another thread about removing message files at the > search from a designated "learn-spam" folder. My next question would > be how to automatically place detected spam into a specific folder for > the user to access or ignore as they deem fit. That would seem to me > to be something for the deliver command and its -m option. But this > might be more of a Dovecot and MTA coordination issue, too (e.g. how > to get the spam detection done in the MTA ... Postfix in my case ... > to become a label of some sort that ends deciding the folder. The -m > option might be harder to get it dynamically set since it would be > hard coded in master.cf for Postfix (so a variable has to be able to > direct it to INBOX in this case). > > But maybe the "standard" way of doing this is to shim another program > between the MTA (Postfix for me) and the LDA (Dovecot deliver) to > dynamically add the -m option on the fly? Lacking any other clever > solution, this seems to me to be the way I could make it work. Maybe > there is a special header deliver could detect, such as "X-Spam: yes"? > > A wiki document on how Dovecot helps (or how to help Dovecot) in the > fight against spam, I think, would be helpful.Get your anti-spam software to add header records to the messages, then use Dovecot LDA Sieve to filter based on those header records. Bill
On Tue, Jun 1, 2010 at 11:01, William Blunn <bill+dovecot at blunn.org> wrote:> Get your anti-spam software to add header records to the messages, then use > Dovecot LDA Sieve to filter based on those header records.So I can run Sieve as part of the deliver? Or does it run soon after that?
-------- Original-Nachricht --------> Datum: Tue, 1 Jun 2010 09:42:18 -0400 > Von: Phil Howard <ttiphil at gmail.com> > An: Dovecot Mailing List <dovecot at dovecot.org> > Betreff: [Dovecot] Dovecot aspects of fighting spam> I see no documents in the Dovecot documents wiki on how Dovecot > features can be used in the fight against spam. One hit came up in a > search, and it was about how to fight spam in the MoinMoin Wiki itself > (e.g. TextCHAs and such). > > I already asked in another thread about removing message files at the > search from a designated "learn-spam" folder. My next question would > be how to automatically place detected spam into a specific folder for > the user to access or ignore as they deem fit. That would seem to me > to be something for the deliver command and its -m option. But this > might be more of a Dovecot and MTA coordination issue, too (e.g. how > to get the spam detection done in the MTA ... Postfix in my case ... > to become a label of some sort that ends deciding the folder. The -m > option might be harder to get it dynamically set since it would be > hard coded in master.cf for Postfix (so a variable has to be able to > direct it to INBOX in this case). > > But maybe the "standard" way of doing this is to shim another program > between the MTA (Postfix for me) and the LDA (Dovecot deliver) to > dynamically add the -m option on the fly? Lacking any other clever > solution, this seems to me to be the way I could make it work. Maybe > there is a special header deliver could detect, such as "X-Spam: yes"? > > A wiki document on how Dovecot helps (or how to help Dovecot) in the > fight against spam, I think, would be helpful. >Maybe you are looking for something like this: https://sourceforge.net/apps/mediawiki/dspam/index.php?title=Filter_results_with_Dovecot_Sieve -- GRATIS f?r alle GMX-Mitglieder: Die maxdome Movie-FLAT! Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01