_t_c_p_d_c_h_k examines your tcp wrapper configuration and reports all potential and real problems it can find. The program examines the _t_c_p_d access control files (by default, these are _/_e_t_c_/_h_o_s_t_s_._a_l_l_o_w and _/_e_t_c_/_h_o_s_t_s_._d_e_n_y), and compares the entries in these files against entries in the _i_n_e_t_d or _t_l_i_d network configuration files.
_t_c_p_d_c_h_k reports problems such as non-existent pathnames; services that appear in _t_c_p_d access control rules, but are not controlled by _t_c_p_d; 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, _t_c_p_d_c_h_k provides a helpful suggestion to fix the problem.
The default locations of the _t_c_p_d 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 (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