source: trunk/athena/bin/attach/getrealm.c @ 8843

/*
 * $Source: /afs/dev.mit.edu/source/repository/athena/bin/attach/getrealm.c,v $
 * $Author: ghudson $
 *
 * Copyright 1988 by the Massachusetts Institute of Technology.
 *
 * For copying and distribution information, please see the file
 * <mit-copyright.h>.
 *
 * routine to convert hostname into realm name.
 */

#include "config.h"
#ifdef OLD_KERBEROS

static char *rcsid_getrealm_c =
  "$Header: /afs/dev.mit.edu/source/repository/athena/bin/attach/getrealm.c,v 1.4 1996-09-19 22:13:13 ghudson Exp $";

#include <mit-copyright.h>
#include <strings.h>
#include <stdio.h>
#include <krb.h>
#include <sys/param.h>

/* for Ultrix and friends ... */
#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 64
#endif

/*
 * krb_realmofhost.
 * Given a fully-qualified domain-style primary host name,
 * return the name of the Kerberos realm for the host.
 * If the hostname contains no discernable domain, or an error occurs,
 * return the local realm name, as supplied by get_krbrlm()
 *
 * The format of each line of the translation file is:
 * domain_name kerberos_realm
 * -or-
 * host_name kerberos_realm
 *
 * domain_name should be of the form .XXX.YYY (e.g. .LCS.MIT.EDU)
 * host names should be in the usual form (e.g. FOO.BAR.BAZ)
 */

static char ret_realm[REALM_SZ+1];

char *
krb_realmofhost(host)
char *host;
{
        char *domain, *trans_idx;
        FILE *trans_file;
        char trans_host[MAXHOSTNAMELEN+1];
        char trans_realm[REALM_SZ+1];
        int retval;

        domain = strchr(host, '.');

        /* prepare default */
        if (domain) {
                strncpy(ret_realm, &domain[1], REALM_SZ);
                ret_realm[REALM_SZ] = '\0';
        } else {
                get_krbrlm(ret_realm, 1);
        }

        if ((trans_file = fopen(KRB_RLM_TRANS, "r")) == (FILE *) 0) {
                /* krb_errno = KRB_NO_TRANS */
                return(ret_realm);
        }
        while (1) {
                if ((retval = fscanf(trans_file, "%s %s",
                                     trans_host, trans_realm)) != 2) {
                        if (retval == EOF) {
                                fclose(trans_file);
                                return(ret_realm);
                        }
                        continue;       /* ignore broken lines */
                }
                trans_host[MAXHOSTNAMELEN] = '\0';
                trans_realm[REALM_SZ] = '\0';
                if (!strcasecmp(trans_host, host)) {
                        /* exact match of hostname, so return the realm */
                        (void) strcpy(ret_realm, trans_realm);
                        fclose(trans_file);
                        return(ret_realm);
                }
                if ((trans_host[0] = '.') && domain) { 
                        /* this is a domain match */
                        if (!strcasecmp(trans_host, domain)) {
                                /* domain match, save for later */
                                (void) strcpy(ret_realm, trans_realm);
                                continue;
                        }
                }
        }
}
#endif