4.3BSD-Reno/share/man/cat3/krb_realmofhost.0

KRB_REALMOFHOST(3)	       4.0	       KRB_REALMOFHOST(3)



NNAAMMEE
     krb_realmofhost, krb_get_phost, krb_get_krbhst,
     krb_get_admhst, krb_get_lrealm - additional Kerberos utility
     routines

SSYYNNOOPPSSIISS
     ##iinncclluuddee <<kkeerrbbeerroossIIVV//kkrrbb..hh>>
     ##iinncclluuddee <<kkeerrbbeerroossIIVV//ddeess..hh>>
     ##iinncclluuddee <<nneettiinneett//iinn..hh>>

     cchhaarr **kkrrbb__rreeaallmmooffhhoosstt((hhoosstt))
     cchhaarr **hhoosstt;;

     cchhaarr **kkrrbb__ggeett__pphhoosstt((aalliiaass))
     cchhaarr **aalliiaass;;

     kkrrbb__ggeett__kkrrbbhhsstt((hhoosstt,,rreeaallmm,,nn))
     cchhaarr **hhoosstt;;
     cchhaarr **rreeaallmm;;
     iinntt nn;;

     kkrrbb__ggeett__aaddmmhhsstt((hhoosstt,,rreeaallmm,,nn))
     cchhaarr **hhoosstt;;
     cchhaarr **rreeaallmm;;
     iinntt nn;;

     kkrrbb__ggeett__llrreeaallmm((rreeaallmm,,nn))
     cchhaarr **rreeaallmm;;
     iinntt nn;;

DDEESSCCRRIIPPTTIIOONN
     _k_r_b__r_e_a_l_m_o_f_h_o_s_t returns the Kerberos realm of the host _h_o_s_t,
     as determined by the translation table
     /_e_t_c/_k_e_r_b_e_r_o_s_I_V/_k_r_b._r_e_a_l_m_s.  _h_o_s_t should be the fully-
     qualified domain-style primary host name of the host in
     question.	In order to prevent certain security attacks,
     this routine must either have _a _p_r_i_o_r_i knowledge of a host's
     realm, or obtain such information securely.

     The format of the translation file is described by
     _k_r_b._r_e_a_l_m_s(5).  If _h_o_s_t exactly matches a host_name line,
     the corresponding realm is returned.  Otherwise, if the
     domain portion of _h_o_s_t matches a domain_name line, the
     corresponding realm is returned.  If _h_o_s_t contains a domain,
     but no translation is found, _h_o_s_t's domain is converted to
     upper-case and returned.  If _h_o_s_t contains no discernable
     domain, or an error occurs, the local realm name, as sup-
     plied by _k_r_b__g_e_t__l_r_e_a_l_m(3), is returned.

     _k_r_b__g_e_t__p_h_o_s_t converts the hostname _a_l_i_a_s (which can be
     either an official name or an alias) into the instance name
     to be used in obtaining Kerberos tickets for most services,



Printed 7/27/90             Kerberos				1






KRB_REALMOFHOST(3)	       4.0	       KRB_REALMOFHOST(3)



     including the Berkeley rcmd suite (rlogin, rcp, rsh).
     The current convention is to return the first segment of the
     official domain-style name after conversion to lower case.

     _k_r_b__g_e_t__k_r_b_h_s_t fills in _h_o_s_t with the hostname of the _nth
     host running a Kerberos key distribution center (KDC) for
     realm _r_e_a_l_m, as specified in the configuration file
     (/_e_t_c/_k_e_r_b_e_r_o_s_I_V/_k_r_b._c_o_n_f).  The configuration file is
     described by _k_r_b._c_o_n_f(5).	If the host is successfully
     filled in, the routine returns KSUCCESS.  If the file cannot
     be opened, and _n equals 1, then the value of KRB_HOST as
     defined in <_k_r_b._h> is filled in, and KSUCCESS is returned.
     If there are fewer than _n hosts running a Kerberos KDC for
     the requested realm, or the configuration file is malformed,
     the routine returns KFAILURE.

     _k_r_b__g_e_t__a_d_m_h_s_t fills in _h_o_s_t with the hostname of the _nth
     host running a Kerberos KDC database administration server
     for realm _r_e_a_l_m, as specified in the configuration file
     (/_e_t_c/_k_e_r_b_e_r_o_s_I_V/_k_r_b._c_o_n_f).  If the file cannot be opened or
     is malformed, or there are fewer than _n hosts running a Ker-
     beros KDC database administration server, the routine
     returns KFAILURE.

     The character arrays used as return values for
     _k_r_b__g_e_t__k_r_b_h_s_t, _k_r_b__g_e_t__a_d_m_h_s_t, should be large enough to
     hold any hostname (MAXHOSTNAMELEN from <sys/param.h>).

     _k_r_b__g_e_t__l_r_e_a_l_m fills in _r_e_a_l_m with the _nth realm of the
     local host, as specified in the configuration file.  _r_e_a_l_m
     should be at least REALM_SZ (from <_k_r_b._h>)characters_l_o_n_g.

SSEEEE AALLSSOO
     kerberos(3), krb.conf(5), krb.realms(5)

FFIILLEESS
     /etc/kerberosIV/krb.realms
			 translation file for host-to-realm map-
			 ping.

     /etc/kerberosIV/krb.conf
			 local realm-name and realm/server confi-
			 guration file.

BBUUGGSS
     The current convention for instance names is too limited;
     the full domain name should be used.

     _k_r_b__g_e_t__l_r_e_a_l_m currently only supports _n = 1.  It should
     really consult the user's ticket cache to determine the
     user's current realm, rather than consulting a file on the
     host.



Printed 7/27/90             Kerberos				2