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Jelmer Vernooij 773cfba9af Avoid including libds/common/roles.h in public loadparm.h header.
Signed-Off-By: Jelmer Vernooij <jelmer@samba.org>
Reviewed-By: Andrew Bartlett <abartlet@samba.org>
Reviewed-By: Stefan Metzmacher <metze@samba.org>
2016-01-13 04:43:23 +01:00

718 lines
21 KiB
C

/*
Unix SMB/CIFS implementation.
Password and authentication handling
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2009
Copyright (C) Gerald Carter 2003
Copyright (C) Stefan Metzmacher 2005
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/time.h"
#include <ldb.h>
#include "libcli/ldap/ldap_ndr.h"
#include "libcli/security/security.h"
#include "auth/auth.h"
#include "../libcli/auth/ntlm_check.h"
#include "auth/ntlm/auth_proto.h"
#include "auth/auth_sam.h"
#include "dsdb/samdb/samdb.h"
#include "dsdb/common/util.h"
#include "param/param.h"
#include "librpc/gen_ndr/ndr_irpc_c.h"
#include "lib/messaging/irpc.h"
#include "libcli/auth/libcli_auth.h"
#include "libds/common/roles.h"
NTSTATUS auth_sam_init(void);
extern const char *user_attrs[];
extern const char *domain_ref_attrs[];
/****************************************************************************
Look for the specified user in the sam, return ldb result structures
****************************************************************************/
static NTSTATUS authsam_search_account(TALLOC_CTX *mem_ctx, struct ldb_context *sam_ctx,
const char *account_name,
struct ldb_dn *domain_dn,
struct ldb_message **ret_msg)
{
int ret;
/* pull the user attributes */
ret = dsdb_search_one(sam_ctx, mem_ctx, ret_msg, domain_dn, LDB_SCOPE_SUBTREE,
user_attrs,
DSDB_SEARCH_SHOW_EXTENDED_DN,
"(&(sAMAccountName=%s)(objectclass=user))",
ldb_binary_encode_string(mem_ctx, account_name));
if (ret == LDB_ERR_NO_SUCH_OBJECT) {
DEBUG(3,("sam_search_user: Couldn't find user [%s] in samdb, under %s\n",
account_name, ldb_dn_get_linearized(domain_dn)));
return NT_STATUS_NO_SUCH_USER;
}
if (ret != LDB_SUCCESS) {
return NT_STATUS_INTERNAL_DB_CORRUPTION;
}
return NT_STATUS_OK;
}
/****************************************************************************
Do a specific test for an smb password being correct, given a smb_password and
the lanman and NT responses.
****************************************************************************/
static NTSTATUS authsam_password_ok(struct auth4_context *auth_context,
TALLOC_CTX *mem_ctx,
uint16_t acct_flags,
const struct samr_Password *lm_pwd,
const struct samr_Password *nt_pwd,
const struct auth_usersupplied_info *user_info,
DATA_BLOB *user_sess_key,
DATA_BLOB *lm_sess_key)
{
NTSTATUS status;
switch (user_info->password_state) {
case AUTH_PASSWORD_PLAIN:
{
const struct auth_usersupplied_info *user_info_temp;
status = encrypt_user_info(mem_ctx, auth_context,
AUTH_PASSWORD_HASH,
user_info, &user_info_temp);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to convert plaintext password to password HASH: %s\n", nt_errstr(status)));
return status;
}
user_info = user_info_temp;
/*fall through*/
}
case AUTH_PASSWORD_HASH:
*lm_sess_key = data_blob(NULL, 0);
*user_sess_key = data_blob(NULL, 0);
status = hash_password_check(mem_ctx,
lpcfg_lanman_auth(auth_context->lp_ctx),
user_info->password.hash.lanman,
user_info->password.hash.nt,
user_info->mapped.account_name,
lm_pwd, nt_pwd);
NT_STATUS_NOT_OK_RETURN(status);
break;
case AUTH_PASSWORD_RESPONSE:
status = ntlm_password_check(mem_ctx,
lpcfg_lanman_auth(auth_context->lp_ctx),
lpcfg_ntlm_auth(auth_context->lp_ctx),
user_info->logon_parameters,
&auth_context->challenge.data,
&user_info->password.response.lanman,
&user_info->password.response.nt,
user_info->mapped.account_name,
user_info->client.account_name,
user_info->client.domain_name,
lm_pwd, nt_pwd,
user_sess_key, lm_sess_key);
NT_STATUS_NOT_OK_RETURN(status);
break;
}
return NT_STATUS_OK;
}
/*
send a message to the drepl server telling it to initiate a
REPL_SECRET getncchanges extended op to fetch the users secrets
*/
static void auth_sam_trigger_repl_secret(struct auth4_context *auth_context,
struct ldb_dn *user_dn)
{
struct dcerpc_binding_handle *irpc_handle;
struct drepl_trigger_repl_secret r;
struct tevent_req *req;
TALLOC_CTX *tmp_ctx;
tmp_ctx = talloc_new(auth_context);
if (tmp_ctx == NULL) {
return;
}
irpc_handle = irpc_binding_handle_by_name(tmp_ctx, auth_context->msg_ctx,
"dreplsrv",
&ndr_table_irpc);
if (irpc_handle == NULL) {
DEBUG(1,(__location__ ": Unable to get binding handle for dreplsrv\n"));
TALLOC_FREE(tmp_ctx);
return;
}
r.in.user_dn = ldb_dn_get_linearized(user_dn);
/*
* This seem to rely on the current IRPC implementation,
* which delivers the message in the _send function.
*
* TODO: we need a ONE_WAY IRPC handle and register
* a callback and wait for it to be triggered!
*/
req = dcerpc_drepl_trigger_repl_secret_r_send(tmp_ctx,
auth_context->event_ctx,
irpc_handle,
&r);
/* we aren't interested in a reply */
talloc_free(req);
TALLOC_FREE(tmp_ctx);
}
/*
* Check that a password is OK, and update badPwdCount if required.
*/
static NTSTATUS authsam_password_check_and_record(struct auth4_context *auth_context,
TALLOC_CTX *mem_ctx,
struct ldb_dn *domain_dn,
struct ldb_message *msg,
uint16_t acct_flags,
const struct auth_usersupplied_info *user_info,
DATA_BLOB *user_sess_key,
DATA_BLOB *lm_sess_key)
{
NTSTATUS nt_status;
NTSTATUS auth_status;
TALLOC_CTX *tmp_ctx;
int i, ret;
int history_len = 0;
struct ldb_context *sam_ctx = auth_context->sam_ctx;
const char * const attrs[] = { "pwdHistoryLength", NULL };
struct ldb_message *dom_msg;
struct samr_Password *lm_pwd;
struct samr_Password *nt_pwd;
tmp_ctx = talloc_new(mem_ctx);
if (tmp_ctx == NULL) {
return NT_STATUS_NO_MEMORY;
}
/*
* This call does more than what it appears to do, it also
* checks for the account lockout.
*
* It is done here so that all parts of Samba that read the
* password refuse to even operate on it if the account is
* locked out, to avoid mistakes like CVE-2013-4496.
*/
nt_status = samdb_result_passwords(tmp_ctx, auth_context->lp_ctx,
msg, &lm_pwd, &nt_pwd);
if (!NT_STATUS_IS_OK(nt_status)) {
TALLOC_FREE(tmp_ctx);
return nt_status;
}
if (lm_pwd == NULL && nt_pwd == NULL) {
bool am_rodc;
if (samdb_rodc(auth_context->sam_ctx, &am_rodc) == LDB_SUCCESS && am_rodc) {
/*
* we don't have passwords for this
* account. We are an RODC, and this account
* may be one for which we either are denied
* REPL_SECRET replication or we haven't yet
* done the replication. We return
* NT_STATUS_NOT_IMPLEMENTED which tells the
* auth code to try the next authentication
* mechanism. We also send a message to our
* drepl server to tell it to try and
* replicate the secrets for this account.
*/
auth_sam_trigger_repl_secret(auth_context, msg->dn);
TALLOC_FREE(tmp_ctx);
return NT_STATUS_NOT_IMPLEMENTED;
}
}
auth_status = authsam_password_ok(auth_context, tmp_ctx,
acct_flags,
lm_pwd, nt_pwd,
user_info,
user_sess_key, lm_sess_key);
if (NT_STATUS_IS_OK(auth_status)) {
if (user_sess_key->data) {
talloc_steal(mem_ctx, user_sess_key->data);
}
if (lm_sess_key->data) {
talloc_steal(mem_ctx, lm_sess_key->data);
}
TALLOC_FREE(tmp_ctx);
return NT_STATUS_OK;
}
*user_sess_key = data_blob_null;
*lm_sess_key = data_blob_null;
if (!NT_STATUS_EQUAL(auth_status, NT_STATUS_WRONG_PASSWORD)) {
TALLOC_FREE(tmp_ctx);
return auth_status;
}
/*
* We only continue if this was a wrong password
* and we'll always return NT_STATUS_WRONG_PASSWORD
* no matter what error happens.
*/
/* pull the domain password property attributes */
ret = dsdb_search_one(sam_ctx, tmp_ctx, &dom_msg, domain_dn, LDB_SCOPE_BASE,
attrs, 0, "objectClass=domain");
if (ret == LDB_SUCCESS) {
history_len = ldb_msg_find_attr_as_uint(dom_msg, "pwdHistoryLength", 0);
} else if (ret == LDB_ERR_NO_SUCH_OBJECT) {
DEBUG(3,("Couldn't find domain %s: %s!\n",
ldb_dn_get_linearized(domain_dn),
ldb_errstring(sam_ctx)));
} else {
DEBUG(3,("error finding domain %s: %s!\n",
ldb_dn_get_linearized(domain_dn),
ldb_errstring(sam_ctx)));
}
for (i = 1; i < MIN(history_len, 3); i++) {
static const struct samr_Password zero_hash;
struct samr_Password zero_string_hash;
struct samr_Password zero_string_des_hash;
struct samr_Password *nt_history_pwd = NULL;
struct samr_Password *lm_history_pwd = NULL;
NTTIME pwdLastSet;
struct timeval tv_now;
NTTIME now;
int allowed_period_mins;
NTTIME allowed_period;
nt_status = samdb_result_passwords_from_history(tmp_ctx,
auth_context->lp_ctx,
msg, i,
&lm_history_pwd,
&nt_history_pwd);
if (!NT_STATUS_IS_OK(nt_status)) {
/*
* If we don't find element 'i' we won't find
* 'i+1' ...
*/
break;
}
/*
* We choose to avoid any issues
* around different LM and NT history
* lengths by only checking the NT
* history
*/
if (nt_history_pwd == NULL) {
/*
* If we don't find element 'i' we won't find
* 'i+1' ...
*/
break;
}
/* Skip over all-zero hashes in the history */
if (memcmp(nt_history_pwd->hash, zero_hash.hash,
sizeof(zero_hash.hash)) == 0) {
continue;
}
/*
* This looks odd, but the password_hash module writes this in if
* (somehow) we didn't have an old NT hash
*/
E_md4hash("", zero_string_hash.hash);
if (memcmp(nt_history_pwd->hash, zero_string_hash.hash, 16) == 0) {
continue;
}
E_deshash("", zero_string_des_hash.hash);
if (!lm_history_pwd || memcmp(lm_history_pwd->hash, zero_string_des_hash.hash, 16) == 0) {
lm_history_pwd = NULL;
}
auth_status = authsam_password_ok(auth_context, tmp_ctx,
acct_flags,
lm_history_pwd,
nt_history_pwd,
user_info,
user_sess_key,
lm_sess_key);
if (!NT_STATUS_IS_OK(auth_status)) {
/*
* If this was not a correct password, try the next
* one from the history
*/
*user_sess_key = data_blob_null;
*lm_sess_key = data_blob_null;
continue;
}
if (i != 1) {
/*
* The authentication was OK, but not against
* the previous password, which is stored at index 1.
*
* We just return the original wrong password.
* This skips the update of the bad pwd count,
* because this is almost certainly user error
* (or automatic login on a computer using a cached
* password from before the password change),
* not an attack.
*/
TALLOC_FREE(tmp_ctx);
return NT_STATUS_WRONG_PASSWORD;
}
if (user_info->password_state != AUTH_PASSWORD_RESPONSE) {
/*
* The authentication was OK against the previous password,
* but it's not a NTLM network authentication.
*
* We just return the original wrong password.
* This skips the update of the bad pwd count,
* because this is almost certainly user error
* (or automatic login on a computer using a cached
* password from before the password change),
* not an attack.
*/
TALLOC_FREE(tmp_ctx);
return NT_STATUS_WRONG_PASSWORD;
}
/*
* If the password was OK, it's a NTLM network authentication
* and it was the previous password.
*
* Now we see if it is within the grace period,
* so that we don't break cached sessions on other computers
* before the user can lock and unlock their other screens
* (resetting their cached password).
*
* See http://support.microsoft.com/kb/906305
* OldPasswordAllowedPeriod ("old password allowed period")
* is specified in minutes. The default is 60.
*/
allowed_period_mins = lpcfg_old_password_allowed_period(auth_context->lp_ctx);
/*
* NTTIME uses 100ns units
*/
allowed_period = allowed_period_mins * 60 * 1000*1000*10;
pwdLastSet = samdb_result_nttime(msg, "pwdLastSet", 0);
tv_now = timeval_current();
now = timeval_to_nttime(&tv_now);
if (now < pwdLastSet) {
/*
* time jump?
*
* We just return the original wrong password.
* This skips the update of the bad pwd count,
* because this is almost certainly user error
* (or automatic login on a computer using a cached
* password from before the password change),
* not an attack.
*/
TALLOC_FREE(tmp_ctx);
return NT_STATUS_WRONG_PASSWORD;
}
if ((now - pwdLastSet) >= allowed_period) {
/*
* The allowed period is over.
*
* We just return the original wrong password.
* This skips the update of the bad pwd count,
* because this is almost certainly user error
* (or automatic login on a computer using a cached
* password from before the password change),
* not an attack.
*/
TALLOC_FREE(tmp_ctx);
return NT_STATUS_WRONG_PASSWORD;
}
/*
* We finally allow the authentication with the
* previous password within the allowed period.
*/
if (user_sess_key->data) {
talloc_steal(mem_ctx, user_sess_key->data);
}
if (lm_sess_key->data) {
talloc_steal(mem_ctx, lm_sess_key->data);
}
TALLOC_FREE(tmp_ctx);
return auth_status;
}
/*
* If we are not in the allowed period or match an old password,
* we didn't return early. Now update the badPwdCount et al.
*/
nt_status = authsam_update_bad_pwd_count(auth_context->sam_ctx,
msg, domain_dn);
if (!NT_STATUS_IS_OK(nt_status)) {
/*
* We need to return the original
* NT_STATUS_WRONG_PASSWORD error, so there isn't
* anything more we can do than write something into
* the log
*/
DEBUG(0, ("Failed to note bad password for user [%s]: %s\n",
user_info->mapped.account_name,
nt_errstr(nt_status)));
}
TALLOC_FREE(tmp_ctx);
return NT_STATUS_WRONG_PASSWORD;
}
static NTSTATUS authsam_authenticate(struct auth4_context *auth_context,
TALLOC_CTX *mem_ctx, struct ldb_context *sam_ctx,
struct ldb_dn *domain_dn,
struct ldb_message *msg,
const struct auth_usersupplied_info *user_info,
DATA_BLOB *user_sess_key, DATA_BLOB *lm_sess_key)
{
NTSTATUS nt_status;
bool interactive = (user_info->password_state == AUTH_PASSWORD_HASH);
uint16_t acct_flags = samdb_result_acct_flags(msg, NULL);
TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
if (!tmp_ctx) {
return NT_STATUS_NO_MEMORY;
}
/* You can only do an interactive login to normal accounts */
if (user_info->flags & USER_INFO_INTERACTIVE_LOGON) {
if (!(acct_flags & ACB_NORMAL)) {
TALLOC_FREE(tmp_ctx);
return NT_STATUS_NO_SUCH_USER;
}
}
nt_status = authsam_password_check_and_record(auth_context, tmp_ctx,
domain_dn, msg, acct_flags,
user_info,
user_sess_key, lm_sess_key);
if (!NT_STATUS_IS_OK(nt_status)) {
TALLOC_FREE(tmp_ctx);
return nt_status;
}
nt_status = authsam_account_ok(tmp_ctx, auth_context->sam_ctx,
user_info->logon_parameters,
domain_dn,
msg,
user_info->workstation_name,
user_info->mapped.account_name,
false, false);
if (!NT_STATUS_IS_OK(nt_status)) {
TALLOC_FREE(tmp_ctx);
return nt_status;
}
nt_status = authsam_logon_success_accounting(auth_context->sam_ctx,
msg, domain_dn,
interactive);
if (!NT_STATUS_IS_OK(nt_status)) {
TALLOC_FREE(tmp_ctx);
return nt_status;
}
if (user_sess_key && user_sess_key->data) {
talloc_steal(mem_ctx, user_sess_key->data);
}
if (lm_sess_key && lm_sess_key->data) {
talloc_steal(mem_ctx, lm_sess_key->data);
}
TALLOC_FREE(tmp_ctx);
return nt_status;
}
static NTSTATUS authsam_check_password_internals(struct auth_method_context *ctx,
TALLOC_CTX *mem_ctx,
const struct auth_usersupplied_info *user_info,
struct auth_user_info_dc **user_info_dc)
{
NTSTATUS nt_status;
const char *account_name = user_info->mapped.account_name;
struct ldb_message *msg;
struct ldb_dn *domain_dn;
DATA_BLOB user_sess_key, lm_sess_key;
TALLOC_CTX *tmp_ctx;
if (ctx->auth_ctx->sam_ctx == NULL) {
DEBUG(0, ("No SAM available, cannot log in users\n"));
return NT_STATUS_INVALID_SYSTEM_SERVICE;
}
if (!account_name || !*account_name) {
/* 'not for me' */
return NT_STATUS_NOT_IMPLEMENTED;
}
tmp_ctx = talloc_new(mem_ctx);
if (!tmp_ctx) {
return NT_STATUS_NO_MEMORY;
}
domain_dn = ldb_get_default_basedn(ctx->auth_ctx->sam_ctx);
if (domain_dn == NULL) {
talloc_free(tmp_ctx);
return NT_STATUS_NO_SUCH_DOMAIN;
}
nt_status = authsam_search_account(tmp_ctx, ctx->auth_ctx->sam_ctx, account_name, domain_dn, &msg);
if (!NT_STATUS_IS_OK(nt_status)) {
talloc_free(tmp_ctx);
return nt_status;
}
nt_status = authsam_authenticate(ctx->auth_ctx, tmp_ctx, ctx->auth_ctx->sam_ctx, domain_dn, msg, user_info,
&user_sess_key, &lm_sess_key);
if (!NT_STATUS_IS_OK(nt_status)) {
talloc_free(tmp_ctx);
return nt_status;
}
nt_status = authsam_make_user_info_dc(tmp_ctx, ctx->auth_ctx->sam_ctx, lpcfg_netbios_name(ctx->auth_ctx->lp_ctx),
lpcfg_sam_name(ctx->auth_ctx->lp_ctx),
domain_dn,
msg,
user_sess_key, lm_sess_key,
user_info_dc);
if (!NT_STATUS_IS_OK(nt_status)) {
talloc_free(tmp_ctx);
return nt_status;
}
talloc_steal(mem_ctx, *user_info_dc);
talloc_free(tmp_ctx);
return NT_STATUS_OK;
}
static NTSTATUS authsam_ignoredomain_want_check(struct auth_method_context *ctx,
TALLOC_CTX *mem_ctx,
const struct auth_usersupplied_info *user_info)
{
if (!user_info->mapped.account_name || !*user_info->mapped.account_name) {
return NT_STATUS_NOT_IMPLEMENTED;
}
return NT_STATUS_OK;
}
/****************************************************************************
Check SAM security (above) but with a few extra checks.
****************************************************************************/
static NTSTATUS authsam_want_check(struct auth_method_context *ctx,
TALLOC_CTX *mem_ctx,
const struct auth_usersupplied_info *user_info)
{
bool is_local_name, is_my_domain;
if (!user_info->mapped.account_name || !*user_info->mapped.account_name) {
return NT_STATUS_NOT_IMPLEMENTED;
}
is_local_name = lpcfg_is_myname(ctx->auth_ctx->lp_ctx,
user_info->mapped.domain_name);
is_my_domain = lpcfg_is_mydomain(ctx->auth_ctx->lp_ctx,
user_info->mapped.domain_name);
/* check whether or not we service this domain/workgroup name */
switch (lpcfg_server_role(ctx->auth_ctx->lp_ctx)) {
case ROLE_STANDALONE:
return NT_STATUS_OK;
case ROLE_DOMAIN_MEMBER:
if (!is_local_name) {
DEBUG(6,("authsam_check_password: %s is not one of my local names (DOMAIN_MEMBER)\n",
user_info->mapped.domain_name));
return NT_STATUS_NOT_IMPLEMENTED;
}
return NT_STATUS_OK;
case ROLE_ACTIVE_DIRECTORY_DC:
if (!is_local_name && !is_my_domain) {
DEBUG(6,("authsam_check_password: %s is not one of my local names or domain name (DC)\n",
user_info->mapped.domain_name));
return NT_STATUS_NOT_IMPLEMENTED;
}
return NT_STATUS_OK;
}
DEBUG(6,("authsam_check_password: lpcfg_server_role() has an undefined value\n"));
return NT_STATUS_NOT_IMPLEMENTED;
}
/* Wrapper for the auth subsystem pointer */
static NTSTATUS authsam_get_user_info_dc_principal_wrapper(TALLOC_CTX *mem_ctx,
struct auth4_context *auth_context,
const char *principal,
struct ldb_dn *user_dn,
struct auth_user_info_dc **user_info_dc)
{
return authsam_get_user_info_dc_principal(mem_ctx, auth_context->lp_ctx, auth_context->sam_ctx,
principal, user_dn, user_info_dc);
}
static const struct auth_operations sam_ignoredomain_ops = {
.name = "sam_ignoredomain",
.want_check = authsam_ignoredomain_want_check,
.check_password = authsam_check_password_internals,
.get_user_info_dc_principal = authsam_get_user_info_dc_principal_wrapper,
.flags = AUTH_METHOD_LOCAL_SAM
};
static const struct auth_operations sam_ops = {
.name = "sam",
.want_check = authsam_want_check,
.check_password = authsam_check_password_internals,
.get_user_info_dc_principal = authsam_get_user_info_dc_principal_wrapper,
.flags = AUTH_METHOD_LOCAL_SAM
};
_PUBLIC_ NTSTATUS auth4_sam_init(void);
_PUBLIC_ NTSTATUS auth4_sam_init(void)
{
NTSTATUS ret;
ret = auth_register(&sam_ops);
if (!NT_STATUS_IS_OK(ret)) {
DEBUG(0,("Failed to register 'sam' auth backend!\n"));
return ret;
}
ret = auth_register(&sam_ignoredomain_ops);
if (!NT_STATUS_IS_OK(ret)) {
DEBUG(0,("Failed to register 'sam_ignoredomain' auth backend!\n"));
return ret;
}
return ret;
}