diff options
Diffstat (limited to 'crypto/heimdal/lib/krb5/get_host_realm.c')
| -rw-r--r-- | crypto/heimdal/lib/krb5/get_host_realm.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/crypto/heimdal/lib/krb5/get_host_realm.c b/crypto/heimdal/lib/krb5/get_host_realm.c new file mode 100644 index 0000000..e8522cb --- /dev/null +++ b/crypto/heimdal/lib/krb5/get_host_realm.c @@ -0,0 +1,194 @@ +/* + * Copyright (c) 1997, 1998, 1999 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" +#include <resolve.h> + +RCSID("$Id: get_host_realm.c,v 1.25 1999/12/11 23:14:07 assar Exp $"); + +/* To automagically find the correct realm of a host (without + * [domain_realm] in krb5.conf) add a text record for your domain with + * the name of your realm, like this: + * + * krb5-realm IN TXT FOO.SE + * + * The search is recursive, so you can add entries for specific + * hosts. To find the realm of host a.b.c, it first tries + * krb5-realm.a.b.c, then krb5-realm.b.c and so on. + * + * Also supported is _kerberos (following draft-ietf-cat-krb-dns-locate-01.txt) + * + */ + +static int +copy_txt_to_realms (struct resource_record *head, + krb5_realm **realms) +{ + struct resource_record *rr; + int n, i; + + for(n = 0, rr = head; rr; rr = rr->next) + if (rr->type == T_TXT) + ++n; + + if (n == 0) + return -1; + + *realms = malloc ((n + 1) * sizeof(krb5_realm)); + if (*realms == NULL) + return -1; + + for (i = 0; i < n + 1; ++i) + (*realms)[i] = NULL; + + for (i = 0, rr = head; rr; rr = rr->next) { + if (rr->type == T_TXT) { + char *tmp; + + tmp = strdup(rr->u.txt); + if (tmp == NULL) { + for (i = 0; i < n; ++i) + free ((*realms)[i]); + free (*realms); + return -1; + } + (*realms)[i] = tmp; + ++i; + } + } + return 0; +} + +static int +dns_find_realm(krb5_context context, + const char *domain, + const char *dom_string, + krb5_realm **realms) +{ + char dom[MAXHOSTNAMELEN]; + struct dns_reply *r; + int ret; + + if(*domain == '.') + domain++; + snprintf(dom, sizeof(dom), "%s.%s.", dom_string, domain); + r = dns_lookup(dom, "TXT"); + if(r == NULL) + return -1; + + ret = copy_txt_to_realms (r->head, realms); + dns_free_data(r); + return ret; +} + +/* + * Try to figure out what realms host in `domain' belong to from the + * configuration file. + */ + +static int +config_find_realm(krb5_context context, + const char *domain, + krb5_realm **realms) +{ + char **tmp = krb5_config_get_strings (context, NULL, + "domain_realm", + domain, + NULL); + + if (tmp == NULL) + return -1; + *realms = tmp; + return 0; +} + +/* + * This function assumes that `host' is a FQDN (and doesn't handle the + * special case of host == NULL either). + * Try to find mapping in the config file or DNS and it that fails, + * fall back to guessing + */ + +krb5_error_code +krb5_get_host_realm_int (krb5_context context, + const char *host, + krb5_realm **realms) +{ + const char *p; + + for (p = host; p != NULL; p = strchr (p + 1, '.')) { + if(config_find_realm(context, p, realms) == 0) + return 0; + else if(dns_find_realm(context, p, "krb5-realm", realms) == 0) + return 0; + else if(dns_find_realm(context, p, "_kerberos", realms) == 0) + return 0; + } + p = strchr(host, '.'); + if(p != NULL) { + p++; + *realms = malloc(2 * sizeof(krb5_realm)); + if (*realms == NULL) + return ENOMEM; + + (*realms)[0] = strdup(p); + if((*realms)[0] == NULL) { + free(*realms); + return ENOMEM; + } + strupr((*realms)[0]); + (*realms)[1] = NULL; + return 0; + } + return KRB5_ERR_HOST_REALM_UNKNOWN; +} + +/* + * Return the realm(s) of `host' as a NULL-terminated list in `realms'. + */ + +krb5_error_code +krb5_get_host_realm(krb5_context context, + const char *host, + krb5_realm **realms) +{ + char hostname[MAXHOSTNAMELEN]; + + if (host == NULL) { + if (gethostname (hostname, sizeof(hostname))) + return errno; + host = hostname; + } + + return krb5_get_host_realm_int (context, host, realms); +} |
