freebsd-dev/crypto/heimdal/lib/hdb/keytab.c

265 lines
6.8 KiB
C

/*
* Copyright (c) 1999 - 2002 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 "hdb_locl.h"
/* keytab backend for HDB databases */
RCSID("$Id: keytab.c,v 1.5 2002/08/26 13:28:11 assar Exp $");
struct hdb_data {
char *dbname;
char *mkey;
};
/*
* the format for HDB keytabs is:
* HDB:[database:mkey]
*/
static krb5_error_code
hdb_resolve(krb5_context context, const char *name, krb5_keytab id)
{
struct hdb_data *d;
const char *db, *mkey;
d = malloc(sizeof(*d));
if(d == NULL) {
krb5_set_error_string(context, "malloc: out of memory");
return ENOMEM;
}
db = name;
mkey = strchr(name, ':');
if(mkey == NULL || mkey[1] == '\0') {
if(*name == '\0')
d->dbname = NULL;
else {
d->dbname = strdup(name);
if(d->dbname == NULL) {
free(d);
krb5_set_error_string(context, "malloc: out of memory");
return ENOMEM;
}
}
d->mkey = NULL;
} else {
if((mkey - db) == 0) {
d->dbname = NULL;
} else {
d->dbname = malloc(mkey - db);
if(d->dbname == NULL) {
free(d);
krb5_set_error_string(context, "malloc: out of memory");
return ENOMEM;
}
memmove(d->dbname, db, mkey - db);
d->dbname[mkey - db] = '\0';
}
d->mkey = strdup(mkey + 1);
if(d->mkey == NULL) {
free(d->dbname);
free(d);
krb5_set_error_string(context, "malloc: out of memory");
return ENOMEM;
}
}
id->data = d;
return 0;
}
static krb5_error_code
hdb_close(krb5_context context, krb5_keytab id)
{
struct hdb_data *d = id->data;
free(d->dbname);
free(d->mkey);
free(d);
return 0;
}
static krb5_error_code
hdb_get_name(krb5_context context,
krb5_keytab id,
char *name,
size_t namesize)
{
struct hdb_data *d = id->data;
snprintf(name, namesize, "%s%s%s",
d->dbname ? d->dbname : "",
(d->dbname || d->mkey) ? ":" : "",
d->mkey ? d->mkey : "");
return 0;
}
static void
set_config (krb5_context context,
krb5_config_binding *binding,
const char **dbname,
const char **mkey)
{
*dbname = krb5_config_get_string(context, binding, "dbname", NULL);
*mkey = krb5_config_get_string(context, binding, "mkey_file", NULL);
}
/*
* try to figure out the database (`dbname') and master-key (`mkey')
* that should be used for `principal'.
*/
static void
find_db (krb5_context context,
const char **dbname,
const char **mkey,
krb5_const_principal principal)
{
const krb5_config_binding *top_bind = NULL;
krb5_config_binding *default_binding = NULL;
krb5_config_binding *db;
krb5_realm *prealm = krb5_princ_realm(context, (krb5_principal)principal);
*dbname = *mkey = NULL;
while ((db = (krb5_config_binding *)
krb5_config_get_next(context,
NULL,
&top_bind,
krb5_config_list,
"kdc",
"database",
NULL)) != NULL) {
const char *p;
p = krb5_config_get_string (context, db, "realm", NULL);
if (p == NULL) {
if(default_binding) {
krb5_warnx(context, "WARNING: more than one realm-less "
"database specification");
krb5_warnx(context, "WARNING: using the first encountered");
} else
default_binding = db;
} else if (strcmp (*prealm, p) == 0) {
set_config (context, db, dbname, mkey);
break;
}
}
if (*dbname == NULL && default_binding != NULL)
set_config (context, default_binding, dbname, mkey);
if (*dbname == NULL)
*dbname = HDB_DEFAULT_DB;
}
/*
* find the keytab entry in `id' for `principal, kvno, enctype' and return
* it in `entry'. return 0 or an error code
*/
static krb5_error_code
hdb_get_entry(krb5_context context,
krb5_keytab id,
krb5_const_principal principal,
krb5_kvno kvno,
krb5_enctype enctype,
krb5_keytab_entry *entry)
{
hdb_entry ent;
krb5_error_code ret;
struct hdb_data *d = id->data;
int i;
HDB *db;
const char *dbname = d->dbname;
const char *mkey = d->mkey;
if (dbname == NULL)
find_db (context, &dbname, &mkey, principal);
ret = hdb_create (context, &db, dbname);
if (ret)
return ret;
ret = hdb_set_master_keyfile (context, db, mkey);
if (ret) {
(*db->destroy)(context, db);
return ret;
}
ret = (*db->open)(context, db, O_RDONLY, 0);
if (ret) {
(*db->destroy)(context, db);
return ret;
}
ent.principal = (krb5_principal)principal;
ret = (*db->fetch)(context, db, HDB_F_DECRYPT, &ent);
(*db->close)(context, db);
(*db->destroy)(context, db);
if(ret == HDB_ERR_NOENTRY)
return KRB5_KT_NOTFOUND;
else if(ret)
return ret;
if(kvno && ent.kvno != kvno) {
hdb_free_entry(context, &ent);
return KRB5_KT_NOTFOUND;
}
if(enctype == 0)
if(ent.keys.len > 0)
enctype = ent.keys.val[0].key.keytype;
ret = KRB5_KT_NOTFOUND;
for(i = 0; i < ent.keys.len; i++) {
if(ent.keys.val[i].key.keytype == enctype) {
krb5_copy_principal(context, principal, &entry->principal);
entry->vno = ent.kvno;
krb5_copy_keyblock_contents(context,
&ent.keys.val[i].key,
&entry->keyblock);
ret = 0;
break;
}
}
hdb_free_entry(context, &ent);
return ret;
}
krb5_kt_ops hdb_kt_ops = {
"HDB",
hdb_resolve,
hdb_get_name,
hdb_close,
hdb_get_entry,
NULL, /* start_seq_get */
NULL, /* next_entry */
NULL, /* end_seq_get */
NULL, /* add */
NULL /* remove */
};