/*
* Copyright (c) 1997 - 2001 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 "kdc_locl.h"
static int
name_type_ok(krb5_context context,
krb5_kdc_configuration *config,
krb5_const_principal principal)
{
int nt = krb5_principal_get_type(context, principal);
if (!krb5_principal_is_krbtgt(context, principal))
return 1;
if (nt == KRB5_NT_SRV_INST || nt == KRB5_NT_UNKNOWN)
return 1;
if (config->strict_nametypes == 0)
return 1;
return 0;
}
struct timeval _kdc_now;
static krb5_error_code
synthesize_hdb_close(krb5_context context, struct HDB *db)
{
(void) context;
(void) db;
return 0;
}
/*
* Synthesize an HDB entry suitable for PKINIT and GSS preauth.
*/
static krb5_error_code
synthesize_client(krb5_context context,
krb5_kdc_configuration *config,
krb5_const_principal princ,
HDB **db,
hdb_entry **h)
{
static HDB null_db;
krb5_error_code ret;
hdb_entry *e;
/* Hope this works! */
null_db.hdb_destroy = synthesize_hdb_close;
null_db.hdb_close = synthesize_hdb_close;
if (db)
*db = &null_db;
ret = (e = calloc(1, sizeof(*e))) ? 0 : krb5_enomem(context);
if (ret == 0) {
e->flags.client = 1;
e->flags.immutable = 1;
e->flags.virtual = 1;
e->flags.synthetic = 1;
e->flags.do_not_store = 1;
e->kvno = 1;
e->keys.len = 0;
e->keys.val = NULL;
e->created_by.time = time(NULL);
e->modified_by = NULL;
e->valid_start = NULL;
e->valid_end = NULL;
e->pw_end = NULL;
e->etypes = NULL;
e->generation = NULL;
e->extensions = NULL;
}
if (ret == 0)
ret = (e->max_renew = calloc(1, sizeof(*e->max_renew))) ?
0 : krb5_enomem(context);
if (ret == 0)
ret = (e->max_life = calloc(1, sizeof(*e->max_life))) ?
0 : krb5_enomem(context);
if (ret == 0)
ret = krb5_copy_principal(context, princ, &e->principal);
if (ret == 0)
ret = krb5_copy_principal(context, princ, &e->created_by.principal);
if (ret == 0) {
/*
* We can't check OCSP in the TGS path, so we can't let tickets for
* synthetic principals live very long.
*/
*(e->max_renew) = config->synthetic_clients_max_renew;
*(e->max_life) = config->synthetic_clients_max_life;
*h = e;
} else if (e) {
hdb_free_entry(context, &null_db, e);
}
return ret;
}
KDC_LIB_FUNCTION krb5_error_code KDC_LIB_CALL
_kdc_db_fetch(krb5_context context,
krb5_kdc_configuration *config,
krb5_const_principal principal,
unsigned flags,
krb5uint32 *kvno_ptr,
HDB **db,
hdb_entry **h)
{
hdb_entry *ent = NULL;
krb5_error_code ret = HDB_ERR_NOENTRY;
int i;
unsigned kvno = 0;
krb5_principal enterprise_principal = NULL;
krb5_const_principal princ;
*h = NULL;
if (db)
*db = NULL;
if (!name_type_ok(context, config, principal))
return HDB_ERR_NOENTRY;
flags |= HDB_F_DECRYPT;
if (kvno_ptr != NULL && *kvno_ptr != 0) {
kvno = *kvno_ptr;
flags |= HDB_F_KVNO_SPECIFIED;
} else {
flags |= HDB_F_ALL_KVNOS;
}
ent = calloc(1, sizeof (*ent));
if (ent == NULL)
return krb5_enomem(context);
if (principal->name.name_type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
if (principal->name.name_string.len != 1) {
ret = KRB5_PARSE_MALFORMED;
krb5_set_error_message(context, ret,
"malformed request: "
"enterprise name with %d name components",
principal->name.name_string.len);
goto out;
}
ret = krb5_parse_name(context, principal->name.name_string.val[0],
&enterprise_principal);
if (ret)
goto out;
}
for (i = 0; i < config->num_db; i++) {
HDB *curdb = config->db[i];
if (db)
*db = curdb;
ret = curdb->hdb_open(context, curdb, O_RDONLY, 0);
if (ret) {
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "Failed to open database: %s", msg);
krb5_free_error_message(context, msg);
continue;
}
princ = principal;
if (!(curdb->hdb_capability_flags & HDB_CAP_F_HANDLE_ENTERPRISE_PRINCIPAL) && enterprise_principal)
princ = enterprise_principal;
ret = hdb_fetch_kvno(context, curdb, princ, flags, 0, 0, kvno, ent);
curdb->hdb_close(context, curdb);
if (ret == HDB_ERR_NOENTRY)
continue; /* Check the other databases */
/*
* This is really important, because errors like
* HDB_ERR_NOT_FOUND_HERE (used to indicate to Samba that
* the RODC on which this code is running does not have
* the key we need, and so a proxy to the KDC is required)
* have specific meaning, and need to be propogated up.
*/
break;
}
switch (ret) {
case HDB_ERR_WRONG_REALM:
case 0:
/*
* the ent->entry.principal just contains hints for the client
* to retry. This is important for enterprise principal routing
* between trusts.
*/
*h = ent;
ent = NULL;
break;
case HDB_ERR_NOENTRY:
if (db)
*db = NULL;
if ((flags & HDB_F_GET_CLIENT) && (flags & HDB_F_SYNTHETIC_OK) &&
config->synthetic_clients) {
ret = synthesize_client(context, config, principal, db, h);
if (ret) {
krb5_set_error_message(context, ret, "could not synthesize "
"HDB client principal entry");
ret = HDB_ERR_NOENTRY;
krb5_prepend_error_message(context, ret, "no such entry found in hdb");
}
} else {
krb5_set_error_message(context, ret, "no such entry found in hdb");
}
break;
default:
if (db)
*db = NULL;
break;
}
out:
krb5_free_principal(context, enterprise_principal);
free(ent);
return ret;
}
KDC_LIB_FUNCTION void KDC_LIB_CALL
_kdc_free_ent(krb5_context context, HDB *db, hdb_entry *ent)
{
hdb_free_entry (context, db, ent);
free (ent);
}
/*
* Use the order list of preferred encryption types and sort the
* available keys and return the most preferred key.
*/
krb5_error_code
_kdc_get_preferred_key(krb5_context context,
krb5_kdc_configuration *config,
hdb_entry *h,
const char *name,
krb5_enctype *enctype,
Key **key)
{
krb5_error_code ret;
int i;
if (config->use_strongest_server_key) {
const krb5_enctype *p = krb5_kerberos_enctypes(context);
for (i = 0; p[i] != ETYPE_NULL; i++) {
if (krb5_enctype_valid(context, p[i]) != 0 &&
!_kdc_is_weak_exception(h->principal, p[i]))
continue;
ret = hdb_enctype2key(context, h, NULL, p[i], key);
if (ret != 0)
continue;
if (enctype != NULL)
*enctype = p[i];
return 0;
}
} else {
*key = NULL;
for (i = 0; i < h->keys.len; i++) {
if (krb5_enctype_valid(context, h->keys.val[i].key.keytype) != 0 &&
!_kdc_is_weak_exception(h->principal, h->keys.val[i].key.keytype))
continue;
ret = hdb_enctype2key(context, h, NULL,
h->keys.val[i].key.keytype, key);
if (ret != 0)
continue;
if (enctype != NULL)
*enctype = (*key)->key.keytype;
return 0;
}
}
krb5_set_error_message(context, EINVAL,
"No valid kerberos key found for %s", name);
return EINVAL; /* XXX */
}
krb5_error_code
_kdc_verify_checksum(krb5_context context,
krb5_crypto crypto,
krb5_key_usage usage,
const krb5_data *data,
Checksum *cksum)
{
krb5_error_code ret;
ret = krb5_verify_checksum(context, crypto, usage,
data->data, data->length,
cksum);
if (ret == KRB5_PROG_SUMTYPE_NOSUPP)
ret = KRB5KDC_ERR_SUMTYPE_NOSUPP;
return ret;
}
/*
* Returns TRUE if a PAC should be included in ticket authorization data.
*
* Per [MS-KILE] 3.3.5.3, PACs are always included for TGTs; for service
* tickets, policy is governed by whether the client explicitly requested
* a PAC be omitted when requesting a TGT, or if the no-auth-data-reqd
* flag is set on the service principal entry.
*
* However, when issuing a cross-realm TGT to an AD realm our PAC might not
* interoperate correctly. Therefore we honor the no-auth-data-reqd HDB entry
* flag on cross-realm TGTs.
*/
krb5_boolean
_kdc_include_pac_p(astgs_request_t r)
{
/* Always include a PAC in root TGTs */
if (krb5_principal_is_krbtgt(r->context, r->server->principal)) {
if (krb5_principal_is_root_krbtgt(r->context, r->server->principal) ||
!r->server->flags.no_auth_data_reqd)
return TRUE;
}
if (r->server->flags.no_auth_data_reqd)
return FALSE;
if (r->server->flags.auth_data_reqd)
return TRUE;
if (r->config->disable_pac)
return FALSE;
return !!(r->pac_attributes & (KRB5_PAC_WAS_REQUESTED | KRB5_PAC_WAS_GIVEN_IMPLICITLY));
}
/*
* Notify the HDB backend and KDC plugin of the audited event.
*/
krb5_error_code
_kdc_audit_request(astgs_request_t r)
{
krb5_error_code ret;
struct HDB *hdb;
ret = _kdc_plugin_audit(r);
if (ret == 0 &&
(hdb = r->clientdb ? r->clientdb : r->config->db[0]) &&
hdb->hdb_audit)
ret = hdb->hdb_audit(r->context, hdb, r->client, (hdb_request_t)r);
return ret;
}