On 13 April 2010 21:05, Dino Ciuffetti <d...@tuxweb.it> wrote: > > Hi. > I'm writing a courier global mailfilter in C to verify DKIM signatures on > incoming mails (in second step it will sign outgoing mails too). > > Its goal would be to play very fast and to consume very little resources, > so I thought to develop a process with unblocking multiplexed i/o > techniques for parallel ux socket accept()/read()/write(), and a thread > pool with a request queue for parallel message filtering operations. > > All the DKIM stuff is handled by libopendkim > (http://www.opendkim.org/libopendkim/index.html) > > The very first alpha implementation is working great, but it seems that > courier feeds my filter with mangled headers, so that any signatures is > bad. > > I tried to tcpdump on an incoming mail that comes from gmail to my courier > server. I compared the incoming mail to the mail feeded by courier. This > is a unified diff: > > --- test.eml 2010-04-13 21:32:21.621063539 +0200 > +++ test.eml.OK 2010-04-13 21:13:13.374040723 +0200 > @@ -14,9 +14,7 @@ > b=jpPHcnCIIS4udQHO59Q23wTjccsgbjpMAcWMnQQhzk8jj89yF4nzjUp8epIMgvPXZL > X1hqt0CJuk7/7XLzGicXrb8FhcTMV9Kj34FVuWY8HBEygxqOf7g9yS9IcIqjOiXAEsij > 5kwsmNao/CyuNN/WNXYFoNmCKyAaQwWBo1H1M= > -Mime-Version: 1.0 > -Content-Type: text/plain; charset=iso-8859-1 > -Content-Transfer-Encoding: 7bit > +MIME-Version: 1.0 > Received: by xx.xxx.xx.xxx with HTTP; Tue, 13 Apr 2010 11:56:09 -0700 (PDT) > Date: Tue, 13 Apr 2010 20:56:09 +0200 > Received: by xx.xxx.xxx.xxx with SMTP id n50mr1106102wel.217.1271184969615; > @@ -25,5 +23,6 @@ > Subject: t > From: dAm2K <xxxx...@gmail.com> > To: Dino <d...@xxxxxx.it> > +Content-Type: text/plain; charset=ISO-8859-1 > > t > > > It seems that: > 1) the header called "MIME-Version" become "Mime-Version" and it also > change position > 2) the header called "Content-Type" change its value some way and its > position > 3) a non existent header called "Content-Transfer-Encoding" get added by > courier > > My first query is: is there a way to avoid courier to do header mangling > or to do it after global mailfilter phase? > Second query: someone want to help me writing the filter release (GPLv2)? > > Ciao e grazie, gente di courier!! > Dino. > > -- > Dino Ciuffetti > Linux System Administrator and Architect > TuxWeb S.r.l. - http://www.tuxweb.it/ > > > > ------------------------------------------------------------------------------ > Download Intel® Parallel Studio Eval > Try the new software tools for yourself. Speed compiling, find bugs > proactively, and fine-tune applications for parallel performance. > See why Intel Parallel Studio got high marks during beta. > http://p.sf.net/sfu/intel-sw-dev > _______________________________________________ > courier-users mailing list > courier-users@lists.sourceforge.net > Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users > Remember that the customer is always right, be prepared to accept and process headers that don't quite conform to the relevant standards in all sorts of interesting and annoying ways. I wrote a signing filter in multi-threaded C a couple of years ago, it has been running at work for some time without any problems. More information (and a link to a source code tarball) at http://web.ptwol.net/sigfilter - hope that's useful.
------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ courier-users mailing list courier-users@lists.sourceforge.net Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
