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 problem.
-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.
The default locations of the tcpd access control tables are: /etc/hosts.allow /etc/hosts.deny
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 (firstname.lastname@example.org), 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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