tcpdchk - tcp wrapper configuration checker


   tcpdchk [-a] [-d] [-i inet_conf] [-v]


   tcpdchk  examines  your  tcp  wrapper  configuration  and  reports  all
   potential and real problems it can find. The program examines the  tcpd
   access  control  files  (by  default,  these  are  /etc/hosts.allow and
   /etc/hosts.deny), and compares  the  entries  in  these  files  against
   entries in the inetd network configuration file.

   tcpdchk  reports problems such as non-existent pathnames; services that
   appear in tcpd access control rules, but are not  controlled  by  tcpd;
   services  that  should  not be wrapped; non-existent host names or non-
   internet address forms; occurrences of host aliases instead of official
   host  names;  hosts  with a name/address conflict; inappropriate use of
   wildcard patterns; inappropriate use of NIS netgroups or references  to
   non-existent NIS netgroups; references to non-existent options; invalid
   arguments to options; and so on.

   Where possible, tcpdchk  provides  a  helpful  suggestion  to  fix  the


   -a     Report  access  control  rules  that  permit  access  without an
          explicit ALLOW keyword.

   -d     Examine  hosts.allow  and  hosts.deny  files  in   the   current
          directory instead of the default ones.

   -i inet_conf
          Specify  this  option  when  tcpdchk  is  unable  to  find  your
          inetd.conf network configuration file, or when you suspect  that
          the program uses the wrong one.

   -v     Display the contents of each access control rule.  Daemon lists,
          client lists, shell commands and options are shown in a  pretty-
          printed  format;  this  makes  it  easier  for  you  to spot any
          discrepancies  between  what  you  want  and  what  the  program


   The default locations of the tcpd access control tables are:



   tcpdmatch(8), explain what tcpd would do in specific cases.
   hosts_access(5), format of the tcpd access control tables.
   hosts_options(5), format of the language extensions.
   inetd.conf(5), format of the inetd control file.


   Wietse Venema (,
   Department of Mathematics and Computing Science,
   Eindhoven University of Technology
   Den Dolech 2, P.O. Box 513,
   5600 MB Eindhoven, The Netherlands



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