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tcpdchk(8)


NAME

   tcpdchk - tcp wrapper configuration checker

SYNOPSIS

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

DESCRIPTION

   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
   problem.

OPTIONS

   -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
          understands.

FILES

   The default locations of the tcpd access control tables are:

   /etc/hosts.allow
   /etc/hosts.deny

SEE ALSO

   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.

AUTHORS

   Wietse Venema (wietse@wzv.win.tue.nl),
   Department of Mathematics and Computing Science,
   Eindhoven University of Technology
   Den Dolech 2, P.O. Box 513,
   5600 MB Eindhoven, The Netherlands

                                                                TCPDCHK(8)



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