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 or tlid network configuration files.

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. This applies only when the extended access control language is enabled (build with -DPROCESS_OPTIONS).
-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 or tlid.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