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/*
Unix SMB/CIFS implementation.
Samba kpasswd implementation
Copyright (c) 2005 Andrew Bartlett <abartlet@samba.org>
Copyright (c) 2016 Andreas Schneider <asn@samba.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "system/kerberos.h"
#include "librpc/gen_ndr/samr.h"
#include "dsdb/samdb/samdb.h"
#include "auth/auth.h"
#include "kdc/kpasswd-helper.h"
bool kpasswd_make_error_reply(TALLOC_CTX *mem_ctx,
krb5_error_code error_code,
const char *error_string,
DATA_BLOB *error_data)
{
bool ok;
char *s;
size_t slen;
if (error_code == 0) {
DBG_DEBUG("kpasswd reply - %s\n", error_string);
} else {
DBG_INFO("kpasswd reply - %s\n", error_string);
}
ok = push_utf8_talloc(mem_ctx, &s, error_string, &slen);
if (!ok) {
return false;
}
/*
* The string 's' has one terminating nul-byte which is also
* reflected by 'slen'. We subtract it from the length.
*/
if (slen < 1) {
talloc_free(s);
return false;
}
slen--;
/* Two bytes are added to the length to account for the error code. */
if (2 + slen < slen) {
talloc_free(s);
return false;
}
error_data->length = 2 + slen;
error_data->data = talloc_size(mem_ctx, error_data->length);
if (error_data->data == NULL) {
talloc_free(s);
return false;
}
RSSVAL(error_data->data, 0, error_code);
memcpy(error_data->data + 2, s, slen);
talloc_free(s);
return true;
}
bool kpasswd_make_pwchange_reply(TALLOC_CTX *mem_ctx,
NTSTATUS status,
enum samPwdChangeReason reject_reason,
struct samr_DomInfo1 *dominfo,
DATA_BLOB *error_blob)
{
const char *reject_string = NULL;
if (NT_STATUS_EQUAL(status, NT_STATUS_NO_SUCH_USER)) {
return kpasswd_make_error_reply(mem_ctx,
KRB5_KPASSWD_ACCESSDENIED,
"No such user when changing password",
error_blob);
} else if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
return kpasswd_make_error_reply(mem_ctx,
KRB5_KPASSWD_ACCESSDENIED,
"Not permitted to change password",
error_blob);
}
if (dominfo != NULL &&
NT_STATUS_EQUAL(status, NT_STATUS_PASSWORD_RESTRICTION)) {
switch (reject_reason) {
case SAM_PWD_CHANGE_PASSWORD_TOO_SHORT:
reject_string =
talloc_asprintf(mem_ctx,
"Password too short, password "
"must be at least %d characters "
"long.",
dominfo->min_password_length);
if (reject_string == NULL) {
reject_string = "Password too short";
}
break;
case SAM_PWD_CHANGE_NOT_COMPLEX:
reject_string = "Password does not meet complexity "
"requirements";
break;
case SAM_PWD_CHANGE_PWD_IN_HISTORY:
reject_string =
talloc_asprintf(mem_ctx,
"Password is already in password "
"history. New password must not "
"match any of your %d previous "
"passwords.",
dominfo->password_history_length);
if (reject_string == NULL) {
reject_string = "Password is already in password "
"history";
}
break;
default:
reject_string = "Password change rejected, password "
"changes may not be permitted on this "
"account, or the minimum password age "
"may not have elapsed.";
break;
}
return kpasswd_make_error_reply(mem_ctx,
KRB5_KPASSWD_SOFTERROR,
reject_string,
error_blob);
}
if (!NT_STATUS_IS_OK(status)) {
reject_string = talloc_asprintf(mem_ctx,
"Failed to set password: %s",
nt_errstr(status));
if (reject_string == NULL) {
reject_string = "Failed to set password";
}
return kpasswd_make_error_reply(mem_ctx,
KRB5_KPASSWD_HARDERROR,
reject_string,
error_blob);
}
return kpasswd_make_error_reply(mem_ctx,
KRB5_KPASSWD_SUCCESS,
"Password changed",
error_blob);
}
NTSTATUS kpasswd_samdb_set_password(TALLOC_CTX *mem_ctx,
struct tevent_context *event_ctx,
struct loadparm_context *lp_ctx,
struct auth_session_info *session_info,
bool is_service_principal,
const char *target_principal_name,
DATA_BLOB *password,
enum samPwdChangeReason *reject_reason,
struct samr_DomInfo1 **dominfo)
{
NTSTATUS status;
struct ldb_context *samdb;
struct ldb_dn *target_dn = NULL;
int rc;
samdb = samdb_connect(mem_ctx,
event_ctx,
lp_ctx,
session_info,
NULL,
0);
if (samdb == NULL) {
return NT_STATUS_INTERNAL_DB_CORRUPTION;
}
DBG_INFO("%s\\%s (%s) is changing password of %s\n",
session_info->info->domain_name,
session_info->info->account_name,
dom_sid_string(mem_ctx,
&session_info->security_token->sids[PRIMARY_USER_SID_INDEX]),
target_principal_name);
rc = ldb_transaction_start(samdb);
if (rc != LDB_SUCCESS) {
return NT_STATUS_TRANSACTION_ABORTED;
}
if (is_service_principal) {
status = crack_service_principal_name(samdb,
mem_ctx,
target_principal_name,
&target_dn,
NULL);
} else {
status = crack_user_principal_name(samdb,
mem_ctx,
target_principal_name,
&target_dn,
NULL);
}
if (!NT_STATUS_IS_OK(status)) {
ldb_transaction_cancel(samdb);
return status;
}
status = samdb_set_password(samdb,
mem_ctx,
target_dn,
NULL, /* domain_dn */
password,
NULL, /* ntNewHash */
DSDB_PASSWORD_RESET,
reject_reason,
dominfo);
if (NT_STATUS_IS_OK(status)) {
rc = ldb_transaction_commit(samdb);
if (rc != LDB_SUCCESS) {
DBG_WARNING("Failed to commit transaction to "
"set password on %s: %s\n",
ldb_dn_get_linearized(target_dn),
ldb_errstring(samdb));
return NT_STATUS_TRANSACTION_ABORTED;
}
} else {
ldb_transaction_cancel(samdb);
}
return status;
}
krb5_error_code kpasswd_check_non_tgt(struct auth_session_info *session_info,
const char **error_string)
{
switch(session_info->ticket_type) {
case TICKET_TYPE_TGT:
/* TGTs are disallowed here. */
*error_string = "A TGT may not be used as a ticket to kpasswd";
return KRB5_KPASSWD_AUTHERROR;
case TICKET_TYPE_NON_TGT:
/* Non-TGTs are permitted, and expected. */
break;
default:
/* In case we forgot to set the type. */
*error_string = "Failed to ascertain that ticket to kpasswd is not a TGT";
return KRB5_KPASSWD_HARDERROR;
}
return 0;
}
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