Provided by: inn2_2.6.5-1_amd64 bug

NAME

       perl-nocem - A NoCeM-on-spool implementation for INN 2.x

SYNOPSIS

       perl-nocem

DESCRIPTION

       NoCeM, which is pronounced No See 'Em, is a protocol enabling authenticated third-parties
       to issue notices which can be used to cancel unwanted articles (like spam and articles in
       moderated newsgroups which were not approved by their moderators).  It can also be used by
       readers as a third-party killfile.  It is intended to eventually replace the protocol for
       third-party cancel messages.

       perl-nocem processes third-party, PGP-signed article cancellation notices.  It is possible
       not to honour all NoCeM notices but only those which are sent by people whom you trust
       (that is to say if you trust the PGP key they use to sign their NoCeM notices).  Indeed,
       it is up to you to decide whether you wish to honour their notices, depending on the
       criteria they use.

       Processing NoCeM notices is easy to set up:

       1.  If not already done, install GnuPG, or an equivalent implementation of the OpenPGP
           standard, to be able to verify the signature of NoCeM notices.  It will provide the
           gpg and gpgv programs.  If GnuPG was already installed when INN was configured, then
           the paths to these programs were taken into account.  Otherwise, you have to set the
           $gpg and $gpgv variables in pathlib/perl/INN/Config.pm to the paths to these programs.

           All still active NoCeM issuers use rather modern PGP keys accepted by both GnuPG 1.x
           and 2.x versions.  It is no longer needed to explicitly use gpg1 to process NoCeM
           notices.

       2.  Import the keys of the NoCeM issuers you trust in order to check the authenticity of
           their notices.  You can run the following command:

               gpg --no-default-keyring --allow-non-selfsigned-uid \
                   --primary-keyring <pathetc>/pgp/ncmring.gpg --no-options \
                   --no-permission-warning --batch --import <key-file>
               chmod 644 <pathetc>/pgp/ncmring.gpg

           where <pathetc> is the value of the pathetc parameter set in inn.conf and <key-file>
           the file containing the key(s) to import.  The keyring must be located in
           <pathetc>/pgp/ncmring.gpg; you only have to create the directory <pathetc>/pgp before
           using gpg (it will automatically generate the ncmring.gpg file) and make sure the news
           user can read this file, once generated.

           The keys of NoCeM issuers can be found in the web site of The NoCeM Registry:
           <http://rosalind.home.xs4all.nl/nocemreg/nocemreg.html>.  You can even download there
           a unique file which contains all the keys.

       3.  Create a nocem.ctl config file in pathetc indicating the NoCeM issuers and notices you
           want to follow.  This permission file contains lines like:

               bleachbot@httrack.com:spam,site
               pgpmoose@killfile.org:pgpmoose-forged-moderation

           This will remove all articles for which the issuer (first part of the line, before the
           colon ":") has issued NoCeM notices corresponding to the criteria specified after the
           colon.  Usually, you just keep the lines corresponding to the keys previously
           installed.

           You will also find information about that on the web site of The NoCeM Registry.  Note
           that INN is shipped with an up-to-date nocem.ctl file already configured with the
           current NoCeM issuers.  (Only the keys installed at the previous step are not
           included, so as to leave you the choice of whom to trust, and download the most recent
           ones, in case they have changed.)

       4.  Add to the newsfeeds file an entry like this one in order to feed perl-nocem the NoCeM
           notices posted to alt.nocem.misc and news.lists.filters, the usual groups where
           notices are sent:

               nocem!\
                   :!*,alt.nocem.misc,news.lists.filters\
                   :Tc,Wf,Ap:<pathbin>/perl-nocem

           with the correct path to perl-nocem, located in <pathbin>.  Then, run "inncheck" to
           ensure the syntax of the modified newsfeeds file is correct, and reload it (via
           "ctlinnd reload newsfeeds 'NoCeM channel feed'").

           Note that you should at least carry news.lists.filters on your news server (or other
           newsgroups where NoCeM notices are sent) if you wish to process them.

       5.  Everything should now work.  However, do not hesitate to manually test perl-nocem with
           a NoCeM notice, using:

               grephistory '<Message-ID>' | perl-nocem

           Indeed, perl-nocem expects tokens on its standard input, and grephistory can easily
           give it the token of a known article, thanks to its Message-ID.

       When you have verified that everything works, you can eventually turn off regular spam
       cancels, if you want, not processing any longer cancels containing "cyberspam" in the
       Path: header (see the refusecybercancels parameter in inn.conf).

FILES

       pathbin/perl-nocem
           The Perl script itself used to process NoCeM notices.

       pathetc/nocem.ctl
           The configuration file which specifies the NoCeM notices to be processed.

       pathetc/pgp/ncmring.gpg
           The keyring which contains the public keys of trusted NoCeM issuers.

BUGS

       The Subject header field body is not checked for the @@NCM string and there is no check
       for the presence of the References header field.

       The Newsgroups pseudo header field body is not checked, but this can be done in
       "local_want_cancel_id()".

       The Hierarchies: header is ignored.

HISTORY

       Copyright 2000 by Miquel van Smoorenburg <miquels@cistron.nl>.

       Copyright 2001 by Marco d'Itri <md@linux.it>.

SEE ALSO

       gpg(1), gpgv(1), grephistory(1), inn.conf(5), newsfeeds(5), pgp(1).