freebsd-dev/crypto/heimdal/lib/krb5/expand_hostname.c
2000-02-24 11:28:20 +00:00

149 lines
4.3 KiB
C

/*
* Copyright (c) 1999 - 2000 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "krb5_locl.h"
RCSID("$Id: expand_hostname.c,v 1.8 2000/02/20 02:25:29 assar Exp $");
static krb5_error_code
copy_hostname(krb5_context context,
const char *orig_hostname,
char **new_hostname)
{
*new_hostname = strdup (orig_hostname);
if (*new_hostname == NULL)
return ENOMEM;
strlwr (*new_hostname);
return 0;
}
/*
* Try to make `orig_hostname' into a more canonical one in the newly
* allocated space returned in `new_hostname'.
*/
krb5_error_code
krb5_expand_hostname (krb5_context context,
const char *orig_hostname,
char **new_hostname)
{
struct addrinfo *ai, *a, hints;
int error;
memset (&hints, 0, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
error = getaddrinfo (orig_hostname, NULL, &hints, &ai);
if (error)
return copy_hostname (context, orig_hostname, new_hostname);
for (a = ai; a != NULL; a = a->ai_next) {
if (a->ai_canonname != NULL) {
*new_hostname = strdup (a->ai_canonname);
freeaddrinfo (ai);
if (*new_hostname == NULL)
return ENOMEM;
else
return 0;
}
}
freeaddrinfo (ai);
return copy_hostname (context, orig_hostname, new_hostname);
}
/*
* handle the case of the hostname being unresolvable and thus identical
*/
static krb5_error_code
vanilla_hostname (krb5_context context,
const char *orig_hostname,
char **new_hostname,
char ***realms)
{
krb5_error_code ret;
ret = copy_hostname (context, orig_hostname, new_hostname);
if (ret)
return ret;
strlwr (*new_hostname);
ret = krb5_get_host_realm (context, *new_hostname, realms);
if (ret) {
free (*new_hostname);
return ret;
}
return 0;
}
/*
* expand `hostname' to a name we believe to be a hostname in newly
* allocated space in `host' and return realms in `realms'.
*/
krb5_error_code
krb5_expand_hostname_realms (krb5_context context,
const char *orig_hostname,
char **new_hostname,
char ***realms)
{
struct addrinfo *ai, *a, hints;
int error;
krb5_error_code ret = 0;
memset (&hints, 0, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
error = getaddrinfo (orig_hostname, NULL, &hints, &ai);
if (error)
return vanilla_hostname (context, orig_hostname, new_hostname,
realms);
for (a = ai; a != NULL; a = a->ai_next) {
if (a->ai_canonname != NULL) {
ret = copy_hostname (context, orig_hostname, new_hostname);
if (ret) {
freeaddrinfo (ai);
return ret;
}
strlwr (*new_hostname);
ret = krb5_get_host_realm (context, *new_hostname, realms);
if (ret == 0) {
freeaddrinfo (ai);
return 0;
}
free (*new_hostname);
}
}
return vanilla_hostname (context, orig_hostname, new_hostname, realms);
}