Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
PMCHECK(1)		     General Commands Manual		      PMCHECK(1)

NAME
     pmcheck - check veracity and applicability of signatures in news articles.

SYNOPSIS
     pmcheck [newsgroups|user] [file]

DESCRIPTION
     Pmcheck  accepts  an  article from the named file (or standard input if not
     specified), and performs certain checks against digital signatures  present
     in  X-Auth: headers in the news articles. There are two common modes of use
     of pmcheck, and these are described separately for simplicity, even  though
     there is considerable ability to mix-and-match.

     The  first  use  is  when a person is reading news, and sees an article and
     wishes to check whether the article is an approved posting to  a  moderated
     newsgroup, or an approved posting from a particular individual user. Piping
     the article through pmcheck will give a list of valid signatures (or signa-
     tures  which couldn't be checked because corresponding PGP public keys were
     unavailable), and of course generate error messages for invalid signatures,
     which indicate either forged or altered articles. Any alteration might have
     been intentional, but bear in mind the possibility that an alteration could
     have been an artifact of the news system, despite precautions against this.

     The second use, and the reason for the existence of the PGP  Moose  system,
     is  when  an  article is automatically checked upon receipt by a designated
     news hub. In this case, a moderated newsgroup or user name (represented  by
     an  electronic mail address) will be specified, and it is considered an er-
     ror if there is no corresponding X-Auth: header, or if for  any  reason  it
     doesn't  check out. Furthermore, there can be a configured file which lists
     pairs of newsgroup/user names, and corresponding PGP user IDs who	are  al-
     lowed  to authorise such postings.  Even a valid signature from an individ-
     ual who is not listed in this file will be considered an error. All X-Auth:
     headers will be checked if their newsgroup/user name appears in the  check-
     ing  file,  the  only  way  in which the argument is special is that such a
     header for that newsgroup or user must appear.  The intention is  that  any
     article  which  fails  this  authentication process will be reported to the
     user or newsgroup moderator(s), and might be automatically cancelled.  This
     is to react quickly to spamming attacks on moderated newsgroups.

EXIT STATUS
     Pmcheck  returns  an  exit status of 0 if everything is all right, and non-
     zero otherwise.  In particular, an exit status of 1 means that the  article
     was  not approved with the PGP Moose when it should have been, and a status
     of 2 is returned for all other authentication problems.

SEE ALSO
     pmapp(1), pmcanon(1) for a description of the fields which go into the sig-
     nature calculation, the PGP User's Manual, the PGP Moose README file for an
     understanding of how it all hangs together.

BUGS
     Currently pmcheck always allows cancel messages to pass, despite  the  fact
     that  pmdaemon  always authenticates them. The potential consequences of an
     automated cancellation-war were simply too horrible to contemplate.

AUTHOR
     Greg Rose, RoSecure Software.

				    PGP Moose			      PMCHECK(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=pmcheck&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

home | help