Mike: Thanks for the quick and elaborate answer. I just commented out the lines in the magic file and recreated magic.mgc. All good now.
Götz Mike Cappella schrieb: > Götz > > On 9/17/2009 11:40 AM, Götz Rieger wrote: >> Hi all, >> >> I've got an issue with amavisd-new banning emails which start with a >> special character (accented E, Hungarian) like in "és " as ms-exe. >> System is SLES 10 SP2, amavisd-new is fairly recent, I've got to look up >> the exact version. >> >> Enconding is: >> Content-Type: text/plain; charset=ISO-8859-2 >> Content-Transfer-Encoding: 8bit >> >> It looks like the Hex representation of the character and MS-DOS COM is >> the same, 0xe9. >> >> Funny enough in newer SuSE versions the line >> >> 0 byte 0xe9 DOS executable (COM) >> >> is commented out in /usr/share/misc/magic, in SLES 10 SP2 it's >> uncommented. So if amavisd-new is using "file" (it does, does it?) it's >> blocked correctly. >> >> But I need to have those emails get through. So my dilemma is: >> >> -Should I just comment the line and risk old style DOS COM executables >> to go through (pretty rare occurence I would say but anyway...) >> >> -Or does anybody know a better way? I reckon using quoted-printable as >> transfer encoding instead of 8bit would avoid the problem, too? >> >> Would be nice to get some thoughts. >> > > I would comment them out personally, if you have email in charsets and > languages that might cause FPs. > > Clearly the simplistic single-byte DOS executable tests are inadequate > to meet today's requirements. There is also (ë = 0xeb and non-breaking > space = 0x8c): > > 0 byte 0x8c DOS executable (COM) > 0 byte 0xeb DOS executable (COM) > > And there might be others that hit too. > > You could do any/all of the following: > > a) check out the latest (cvs) version of file(1) to see if the issue has > been addressed: it is still a problem in 5.03. > > b) comment out the offending magic entries > > c) contact the file(1) maintainer Christos Zoulas over at > http://mx.gw.com/mailman/listinfo/file at get some advice/suggestions. > > d) create your own magic entries in $HOME/magic or $HOME/magic.mgc > (where $HOME is amavis' $HOME) that catch and usurp detection for the > most common cases for your situation (eg, here's one for "és"): > > 0 string \xe9\x73 ISO-8859 text > > Downsides with this solution are 1) you'll need a number of > permutations, and 2) any might overlap with actual DOS executables, > effectively implementing solution (b) above. > > e) create and amavis entry to allow DOS executables returned from file. > > Hope this helps. > -- > Mike > > > ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ AMaViS-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/amavis-user AMaViS-FAQ:http://www.amavis.org/amavis-faq.php3 AMaViS-HowTos:http://www.amavis.org/howto/
