OpenSolaris_b135/lib/gss_mechs/mech_krb5/krb5/os/def_realm.c
/*
* lib/krb5/os/def_realm.c
*
* Copyright 1990,1991 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* krb5_get_default_realm(), krb5_set_default_realm(),
* krb5_free_default_realm() functions.
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include "k5-int.h"
#include "os-proto.h"
#include <stdio.h>
/*
* Solaris Kerberos:
* For krb5int_foreach_localaddr()
*/
#include "foreachaddr.h"
#ifdef KRB5_DNS_LOOKUP
#ifdef WSHELPER
#include <wshelper.h>
#else /* WSHELPER */
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <netdb.h>
#endif /* WSHELPER */
/* for old Unixes and friends ... */
#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 64
#endif
#define MAX_DNS_NAMELEN (15*(MAXHOSTNAMELEN + 1)+1)
#endif /* KRB5_DNS_LOOKUP */
/*
* Solaris Kerberos:
* The following prototype is needed because it is a
* private interface that does not have a prototype in any .h
*/
extern struct hostent *res_gethostbyaddr(const char *addr, int len, int type);
/*
* Solaris Kerberos:
* krb5int_address_get_realm() given an address (either IPv4 or IPv6) tries to
* find a realm based on the DNS name of that address. Assumes that its being
* used as a callback for krb5int_foreach_localaddr().
*/
static int krb5int_address_get_realm(void *data, struct sockaddr *addr) {
krb5_context context = data;
struct hostent *he = NULL;
switch (addr->sa_family) {
case AF_INET:
he = res_gethostbyaddr((char*)(&sa2sin(addr)->sin_addr),
sizeof(sa2sin(addr)->sin_addr), AF_INET);
break;
case AF_INET6:
he = res_gethostbyaddr(
(char*)(&sa2sin6(addr)->sin6_addr),
sizeof(sa2sin6(addr)->sin6_addr), AF_INET6);
break;
}
if (he) {
/* Try to find realm using returned DNS name */
krb5int_fqdn_get_realm(context, he->h_name,
&context->default_realm);
/* If a realm was found return 1 to immediately halt
* krb5int_foreach_localaddr()
*/
if (context->default_realm != 0) {
return (1);
}
}
return (0);
}
/*
* Retrieves the default realm to be used if no user-specified realm is
* available. [e.g. to interpret a user-typed principal name with the
* realm omitted for convenience]
*
* returns system errors, NOT_ENOUGH_SPACE, KV5M_CONTEXT
*/
/*
* Implementation: the default realm is stored in a configuration file,
* named by krb5_config_file; the first token in this file is taken as
* the default local realm name.
*/
krb5_error_code KRB5_CALLCONV
krb5_get_default_realm(krb5_context context, char **lrealm)
{
char *realm = 0;
char *cp;
char localhost[MAX_DNS_NAMELEN+1];
krb5_error_code retval;
(void) memset(localhost, 0, sizeof(localhost));
if (!context || (context->magic != KV5M_CONTEXT))
return KV5M_CONTEXT;
if (!context->default_realm) {
context->default_realm = 0;
if (context->profile != 0) {
retval = profile_get_string(context->profile, "libdefaults",
"default_realm", 0, 0,
&realm);
if (!retval && realm) {
context->default_realm = malloc(strlen(realm) + 1);
if (!context->default_realm) {
profile_release_string(realm);
return ENOMEM;
}
strcpy(context->default_realm, realm);
profile_release_string(realm);
}
}
if (context->default_realm == 0) {
#ifdef KRB5_DNS_LOOKUP
if (_krb5_use_dns_realm(context)) {
/*
* Since this didn't appear in our config file, try looking
* it up via DNS. Look for a TXT records of the form:
*
* _kerberos.<localhost>
* _kerberos.<domainname>
* _kerberos.<searchlist>
*
*/
char * p;
krb5int_get_fq_local_hostname (localhost, sizeof(localhost));
if ( localhost[0] ) {
p = localhost;
do {
retval = krb5_try_realm_txt_rr("_kerberos", p,
&context->default_realm);
p = strchr(p,'.');
if (p)
p++;
} while (retval && p && p[0]);
if (retval)
retval = krb5_try_realm_txt_rr("_kerberos", "",
&context->default_realm);
} else {
retval = krb5_try_realm_txt_rr("_kerberos", "",
&context->default_realm);
}
if (retval) {
return(KRB5_CONFIG_NODEFREALM);
}
} else
#endif /* KRB5_DNS_LOOKUP */
{
/*
* Solaris Kerberos:
* Try to find a realm based on one of the local IP addresses
*/
(void) krb5int_foreach_localaddr(context,
krb5int_address_get_realm, 0, 0);
/*
* Solaris Kerberos:
* As a final fallback try to find a realm based on the resolver search
* list
*/
if (context->default_realm == 0) {
struct __res_state res;
int i;
(void) memset(&res, 0, sizeof (res));
if (res_ninit(&res) == 0) {
for (i = 0; res.dnsrch[i]; i++) {
krb5int_domain_get_realm(context,
res.dnsrch[i], &context->default_realm);
if (context->default_realm != 0)
break;
}
res_ndestroy(&res);
}
}
}
}
}
if (context->default_realm == 0)
return(KRB5_CONFIG_NODEFREALM);
if (context->default_realm[0] == 0) {
free (context->default_realm);
context->default_realm = 0;
return KRB5_CONFIG_NODEFREALM;
}
realm = context->default_realm;
/*LINTED*/
if (!(*lrealm = cp = malloc((unsigned int) strlen(realm) + 1)))
return ENOMEM;
strcpy(cp, realm);
return(0);
}
krb5_error_code KRB5_CALLCONV
krb5_set_default_realm(krb5_context context, const char *lrealm)
{
if (!context || (context->magic != KV5M_CONTEXT))
return KV5M_CONTEXT;
if (context->default_realm) {
free(context->default_realm);
context->default_realm = 0;
}
/* Allow the user to clear the default realm setting by passing in
NULL */
if (!lrealm) return 0;
context->default_realm = malloc(strlen (lrealm) + 1);
if (!context->default_realm)
return ENOMEM;
strcpy(context->default_realm, lrealm);
return(0);
}
/*ARGSUSED*/
void KRB5_CALLCONV
krb5_free_default_realm(krb5_context context, char *lrealm)
{
free (lrealm);
}