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samba-mirror/source3/auth/token_util.c
Stefan Metzmacher 7f47f9e1f2 s3:auth: remove static from finalize_local_nt_token()
BUG: https://bugzilla.samba.org/show_bug.cgi?id=13328

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
2018-03-15 21:54:17 +01:00

1238 lines
32 KiB
C

/*
* Unix SMB/CIFS implementation.
* Authentication utility functions
* Copyright (C) Andrew Tridgell 1992-1998
* Copyright (C) Andrew Bartlett 2001
* Copyright (C) Jeremy Allison 2000-2001
* Copyright (C) Rafal Szczesniak 2002
* Copyright (C) Volker Lendecke 2006
* Copyright (C) Michael Adam 2007
*
* 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/>.
*/
/* functions moved from auth/auth_util.c to minimize linker deps */
#include "includes.h"
#include "lib/util_unixsids.h"
#include "system/passwd.h"
#include "auth.h"
#include "secrets.h"
#include "../lib/util/memcache.h"
#include "../librpc/gen_ndr/netlogon.h"
#include "../libcli/security/security.h"
#include "../lib/util/util_pw.h"
#include "passdb.h"
#include "lib/privileges.h"
/****************************************************************************
Check for a SID in an struct security_token
****************************************************************************/
bool nt_token_check_sid ( const struct dom_sid *sid, const struct security_token *token )
{
if ( !sid || !token )
return False;
return security_token_has_sid(token, sid);
}
bool nt_token_check_domain_rid( struct security_token *token, uint32_t rid )
{
struct dom_sid domain_sid;
/* if we are a domain member, the get the domain SID, else for
a DC or standalone server, use our own SID */
if ( lp_server_role() == ROLE_DOMAIN_MEMBER ) {
if ( !secrets_fetch_domain_sid( lp_workgroup(),
&domain_sid ) ) {
DEBUG(1,("nt_token_check_domain_rid: Cannot lookup "
"SID for domain [%s]\n", lp_workgroup()));
return False;
}
}
else
sid_copy( &domain_sid, get_global_sam_sid() );
sid_append_rid( &domain_sid, rid );
return nt_token_check_sid( &domain_sid, token );\
}
/******************************************************************************
Create a token for the root user to be used internally by smbd.
This is similar to running under the context of the LOCAL_SYSTEM account
in Windows. This is a read-only token. Do not modify it or free() it.
Create a copy if you need to change it.
******************************************************************************/
struct security_token *get_root_nt_token( void )
{
struct security_token *token, *for_cache;
struct dom_sid u_sid, g_sid;
struct passwd *pw;
void *cache_data;
cache_data = memcache_lookup_talloc(
NULL, SINGLETON_CACHE_TALLOC,
data_blob_string_const_null("root_nt_token"));
if (cache_data != NULL) {
return talloc_get_type_abort(
cache_data, struct security_token);
}
if ( !(pw = getpwuid(0)) ) {
if ( !(pw = getpwnam("root")) ) {
DEBUG(0,("get_root_nt_token: both getpwuid(0) "
"and getpwnam(\"root\") failed!\n"));
return NULL;
}
}
/* get the user and primary group SIDs; although the
BUILTIN\Administrators SId is really the one that matters here */
uid_to_sid(&u_sid, pw->pw_uid);
gid_to_sid(&g_sid, pw->pw_gid);
token = create_local_nt_token(talloc_tos(), &u_sid, False,
1, &global_sid_Builtin_Administrators);
security_token_set_privilege(token, SEC_PRIV_DISK_OPERATOR);
for_cache = token;
memcache_add_talloc(
NULL, SINGLETON_CACHE_TALLOC,
data_blob_string_const_null("root_nt_token"), &for_cache);
return token;
}
/*
* Add alias SIDs from memberships within the partially created token SID list
*/
NTSTATUS add_aliases(const struct dom_sid *domain_sid,
struct security_token *token)
{
uint32_t *aliases;
size_t i, num_aliases;
NTSTATUS status;
TALLOC_CTX *tmp_ctx;
if (!(tmp_ctx = talloc_init("add_aliases"))) {
return NT_STATUS_NO_MEMORY;
}
aliases = NULL;
num_aliases = 0;
status = pdb_enum_alias_memberships(tmp_ctx, domain_sid,
token->sids,
token->num_sids,
&aliases, &num_aliases);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(10, ("pdb_enum_alias_memberships failed: %s\n",
nt_errstr(status)));
goto done;
}
for (i=0; i<num_aliases; i++) {
struct dom_sid alias_sid;
sid_compose(&alias_sid, domain_sid, aliases[i]);
status = add_sid_to_array_unique(token, &alias_sid,
&token->sids,
&token->num_sids);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0, ("add_sid_to_array failed\n"));
goto done;
}
}
done:
TALLOC_FREE(tmp_ctx);
return NT_STATUS_OK;
}
/*******************************************************************
*******************************************************************/
static NTSTATUS add_builtin_administrators(struct security_token *token,
const struct dom_sid *dom_sid)
{
struct dom_sid domadm;
NTSTATUS status;
/* nothing to do if we aren't in a domain */
if ( !(IS_DC || lp_server_role()==ROLE_DOMAIN_MEMBER) ) {
return NT_STATUS_OK;
}
/* Find the Domain Admins SID */
if ( IS_DC ) {
sid_copy( &domadm, get_global_sam_sid() );
} else {
if (dom_sid == NULL) {
return NT_STATUS_INVALID_PARAMETER_MIX;
}
sid_copy(&domadm, dom_sid);
}
sid_append_rid( &domadm, DOMAIN_RID_ADMINS );
/* Add Administrators if the user beloongs to Domain Admins */
if ( nt_token_check_sid( &domadm, token ) ) {
status = add_sid_to_array(token,
&global_sid_Builtin_Administrators,
&token->sids, &token->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
}
return NT_STATUS_OK;
}
static NTSTATUS add_builtin_guests(struct security_token *token,
const struct dom_sid *dom_sid)
{
struct dom_sid tmp_sid;
NTSTATUS status;
/*
* First check the local GUEST account.
*/
sid_copy(&tmp_sid, get_global_sam_sid());
sid_append_rid(&tmp_sid, DOMAIN_RID_GUEST);
if (nt_token_check_sid(&tmp_sid, token)) {
status = add_sid_to_array_unique(token,
&global_sid_Builtin_Guests,
&token->sids, &token->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
return NT_STATUS_OK;
}
/*
* First check the local GUESTS group.
*/
sid_copy(&tmp_sid, get_global_sam_sid());
sid_append_rid(&tmp_sid, DOMAIN_RID_GUESTS);
if (nt_token_check_sid(&tmp_sid, token)) {
status = add_sid_to_array_unique(token,
&global_sid_Builtin_Guests,
&token->sids, &token->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
return NT_STATUS_OK;
}
if (lp_server_role() != ROLE_DOMAIN_MEMBER) {
return NT_STATUS_OK;
}
if (dom_sid == NULL) {
return NT_STATUS_INVALID_PARAMETER_MIX;
}
/*
* First check the domain GUESTS group.
*/
sid_copy(&tmp_sid, dom_sid);
sid_append_rid(&tmp_sid, DOMAIN_RID_GUESTS);
if (nt_token_check_sid(&tmp_sid, token)) {
status = add_sid_to_array_unique(token,
&global_sid_Builtin_Guests,
&token->sids, &token->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
return NT_STATUS_OK;
}
return NT_STATUS_OK;
}
static NTSTATUS add_local_groups(struct security_token *result,
bool is_guest);
NTSTATUS get_user_sid_info3_and_extra(const struct netr_SamInfo3 *info3,
const struct extra_auth_info *extra,
struct dom_sid *sid)
{
/* USER SID */
if (info3->base.rid == (uint32_t)(-1)) {
/* this is a signal the user was fake and generated,
* the actual SID we want to use is stored in the extra
* sids */
if (is_null_sid(&extra->user_sid)) {
/* we couldn't find the user sid, bail out */
DEBUG(3, ("Invalid user SID\n"));
return NT_STATUS_UNSUCCESSFUL;
}
sid_copy(sid, &extra->user_sid);
} else {
sid_copy(sid, info3->base.domain_sid);
sid_append_rid(sid, info3->base.rid);
}
return NT_STATUS_OK;
}
NTSTATUS create_local_nt_token_from_info3(TALLOC_CTX *mem_ctx,
bool is_guest,
const struct netr_SamInfo3 *info3,
const struct extra_auth_info *extra,
struct security_token **ntok)
{
struct security_token *usrtok = NULL;
uint32_t session_info_flags = 0;
NTSTATUS status;
int i;
DEBUG(10, ("Create local NT token for %s\n",
info3->base.account_name.string));
usrtok = talloc_zero(mem_ctx, struct security_token);
if (!usrtok) {
DEBUG(0, ("talloc failed\n"));
return NT_STATUS_NO_MEMORY;
}
/* Add the user and primary group sid FIRST */
/* check if the user rid is the special "Domain Guests" rid.
* If so pick the first sid for the extra sids instead as it
* is a local fake account */
usrtok->sids = talloc_array(usrtok, struct dom_sid, 2);
if (!usrtok->sids) {
TALLOC_FREE(usrtok);
return NT_STATUS_NO_MEMORY;
}
usrtok->num_sids = 2;
status = get_user_sid_info3_and_extra(info3, extra, &usrtok->sids[0]);
if (!NT_STATUS_IS_OK(status)) {
TALLOC_FREE(usrtok);
return status;
}
/* GROUP SID */
if (info3->base.primary_gid == (uint32_t)(-1)) {
/* this is a signal the user was fake and generated,
* the actual SID we want to use is stored in the extra
* sids */
if (is_null_sid(&extra->pgid_sid)) {
/* we couldn't find the user sid, bail out */
DEBUG(3, ("Invalid group SID\n"));
TALLOC_FREE(usrtok);
return NT_STATUS_UNSUCCESSFUL;
}
sid_copy(&usrtok->sids[1], &extra->pgid_sid);
} else {
sid_copy(&usrtok->sids[1], info3->base.domain_sid);
sid_append_rid(&usrtok->sids[1],
info3->base.primary_gid);
}
/* Now the SIDs we got from authentication. These are the ones from
* the info3 struct or from the pdb_enum_group_memberships, depending
* on who authenticated the user.
* Note that we start the for loop at "1" here, we already added the
* first group sid as primary above. */
for (i = 0; i < info3->base.groups.count; i++) {
struct dom_sid tmp_sid;
sid_copy(&tmp_sid, info3->base.domain_sid);
sid_append_rid(&tmp_sid, info3->base.groups.rids[i].rid);
status = add_sid_to_array_unique(usrtok, &tmp_sid,
&usrtok->sids,
&usrtok->num_sids);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to add SID to nt token\n"));
TALLOC_FREE(usrtok);
return status;
}
}
/* now also add extra sids if they are not the special user/group
* sids */
for (i = 0; i < info3->sidcount; i++) {
status = add_sid_to_array_unique(usrtok,
info3->sids[i].sid,
&usrtok->sids,
&usrtok->num_sids);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to add SID to nt token\n"));
TALLOC_FREE(usrtok);
return status;
}
}
status = add_local_groups(usrtok, is_guest);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to add local groups\n"));
TALLOC_FREE(usrtok);
return status;
}
session_info_flags |= AUTH_SESSION_INFO_DEFAULT_GROUPS;
if (!is_guest) {
session_info_flags |= AUTH_SESSION_INFO_AUTHENTICATED;
}
status = finalize_local_nt_token(usrtok, session_info_flags);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to finalize nt token\n"));
TALLOC_FREE(usrtok);
return status;
}
*ntok = usrtok;
return NT_STATUS_OK;
}
/*******************************************************************
Create a NT token for the user, expanding local aliases
*******************************************************************/
struct security_token *create_local_nt_token(TALLOC_CTX *mem_ctx,
const struct dom_sid *user_sid,
bool is_guest,
int num_groupsids,
const struct dom_sid *groupsids)
{
struct security_token *result = NULL;
int i;
NTSTATUS status;
uint32_t session_info_flags = 0;
DEBUG(10, ("Create local NT token for %s\n",
sid_string_dbg(user_sid)));
if (!(result = talloc_zero(mem_ctx, struct security_token))) {
DEBUG(0, ("talloc failed\n"));
return NULL;
}
/* Add the user and primary group sid */
status = add_sid_to_array(result, user_sid,
&result->sids, &result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
TALLOC_FREE(result);
return NULL;
}
/* For guest, num_groupsids may be zero. */
if (num_groupsids) {
status = add_sid_to_array(result, &groupsids[0],
&result->sids,
&result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
TALLOC_FREE(result);
return NULL;
}
}
/* Now the SIDs we got from authentication. These are the ones from
* the info3 struct or from the pdb_enum_group_memberships, depending
* on who authenticated the user.
* Note that we start the for loop at "1" here, we already added the
* first group sid as primary above. */
for (i=1; i<num_groupsids; i++) {
status = add_sid_to_array_unique(result, &groupsids[i],
&result->sids,
&result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
TALLOC_FREE(result);
return NULL;
}
}
status = add_local_groups(result, is_guest);
if (!NT_STATUS_IS_OK(status)) {
TALLOC_FREE(result);
return NULL;
}
session_info_flags |= AUTH_SESSION_INFO_DEFAULT_GROUPS;
if (!is_guest) {
session_info_flags |= AUTH_SESSION_INFO_AUTHENTICATED;
}
status = finalize_local_nt_token(result, session_info_flags);
if (!NT_STATUS_IS_OK(status)) {
TALLOC_FREE(result);
return NULL;
}
if (is_guest) {
/*
* It's ugly, but for now it's
* needed to add Builtin_Guests
* here, the "local" token only
* consist of S-1-22-* SIDs
* and finalize_local_nt_token()
* doesn't have the chance to
* to detect it need to
* add Builtin_Guests via
* add_builtin_guests().
*/
status = add_sid_to_array_unique(result,
&global_sid_Builtin_Guests,
&result->sids,
&result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to add SID to nt token\n"));
TALLOC_FREE(result);
return NULL;
}
}
return result;
}
/***************************************************
Merge in any groups from /etc/group.
***************************************************/
static NTSTATUS add_local_groups(struct security_token *result,
bool is_guest)
{
gid_t *gids = NULL;
uint32_t getgroups_num_group_sids = 0;
struct passwd *pass = NULL;
TALLOC_CTX *tmp_ctx = talloc_stackframe();
int i;
if (is_guest) {
/*
* Guest is a special case. It's always
* a user that can be looked up, but
* result->sids[0] is set to DOMAIN\Guest.
* Lookup by account name instead.
*/
pass = Get_Pwnam_alloc(tmp_ctx, lp_guest_account());
} else {
uid_t uid;
/* For non-guest result->sids[0] is always the user sid. */
if (!sid_to_uid(&result->sids[0], &uid)) {
/*
* Non-mappable SID like SYSTEM.
* Can't be in any /etc/group groups.
*/
TALLOC_FREE(tmp_ctx);
return NT_STATUS_OK;
}
pass = getpwuid_alloc(tmp_ctx, uid);
if (pass == NULL) {
DEBUG(1, ("SID %s -> getpwuid(%u) failed\n",
sid_string_dbg(&result->sids[0]),
(unsigned int)uid));
}
}
if (!pass) {
TALLOC_FREE(tmp_ctx);
return NT_STATUS_UNSUCCESSFUL;
}
/*
* Now we must get any groups this user has been
* added to in /etc/group and merge them in.
* This has to be done in every code path
* that creates an NT token, as remote users
* may have been added to the local /etc/group
* database. Tokens created merely from the
* info3 structs (via the DC or via the krb5 PAC)
* won't have these local groups. Note the
* groups added here will only be UNIX groups
* (S-1-22-2-XXXX groups) as getgroups_unix_user()
* turns off winbindd before calling getgroups().
*
* NB. This is duplicating work already
* done in the 'unix_user:' case of
* create_token_from_sid() but won't
* do anything other than be inefficient
* in that case.
*/
if (!getgroups_unix_user(tmp_ctx, pass->pw_name, pass->pw_gid,
&gids, &getgroups_num_group_sids)) {
DEBUG(1, ("getgroups_unix_user for user %s failed\n",
pass->pw_name));
TALLOC_FREE(tmp_ctx);
return NT_STATUS_UNSUCCESSFUL;
}
for (i=0; i<getgroups_num_group_sids; i++) {
NTSTATUS status;
struct dom_sid grp_sid;
gid_to_sid(&grp_sid, gids[i]);
status = add_sid_to_array_unique(result,
&grp_sid,
&result->sids,
&result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to add UNIX SID to nt token\n"));
TALLOC_FREE(tmp_ctx);
return status;
}
}
TALLOC_FREE(tmp_ctx);
return NT_STATUS_OK;
}
NTSTATUS finalize_local_nt_token(struct security_token *result,
uint32_t session_info_flags)
{
struct dom_sid _dom_sid = { 0, };
struct dom_sid *domain_sid = NULL;
NTSTATUS status;
struct acct_info *info;
bool ok;
result->privilege_mask = 0;
result->rights_mask = 0;
if (result->num_sids == 0) {
return NT_STATUS_INVALID_TOKEN;
}
if (session_info_flags & AUTH_SESSION_INFO_DEFAULT_GROUPS) {
status = add_sid_to_array(result, &global_sid_World,
&result->sids, &result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
status = add_sid_to_array(result, &global_sid_Network,
&result->sids, &result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
}
/*
* Don't expand nested groups of system, anonymous etc
*
* Note that they still get SID_WORLD and SID_NETWORK
* for now in order let existing tests pass.
*
* But SYSTEM doesn't get AUTHENTICATED_USERS
* and ANONYMOUS doesn't get BUILTIN GUESTS anymore.
*/
if (security_token_is_anonymous(result)) {
return NT_STATUS_OK;
}
if (security_token_is_system(result)) {
result->privilege_mask = ~0;
return NT_STATUS_OK;
}
if (session_info_flags & AUTH_SESSION_INFO_AUTHENTICATED) {
status = add_sid_to_array(result,
&global_sid_Authenticated_Users,
&result->sids,
&result->num_sids);
if (!NT_STATUS_IS_OK(status)) {
return status;
}
}
/* Add in BUILTIN sids */
become_root();
ok = secrets_fetch_domain_sid(lp_workgroup(), &_dom_sid);
if (ok) {
domain_sid = &_dom_sid;
} else {
DEBUG(3, ("Failed to fetch domain sid for %s\n",
lp_workgroup()));
}
unbecome_root();
info = talloc_zero(talloc_tos(), struct acct_info);
if (info == NULL) {
DEBUG(0, ("talloc failed!\n"));
return NT_STATUS_NO_MEMORY;
}
/* Deal with the BUILTIN\Administrators group. If the SID can
be resolved then assume that the add_aliasmem( S-1-5-32 )
handled it. */
status = pdb_get_aliasinfo(&global_sid_Builtin_Administrators, info);
if (!NT_STATUS_IS_OK(status)) {
become_root();
status = create_builtin_administrators(domain_sid);
unbecome_root();
if (NT_STATUS_EQUAL(status, NT_STATUS_PROTOCOL_UNREACHABLE)) {
/* Add BUILTIN\Administrators directly to token. */
status = add_builtin_administrators(result, domain_sid);
if ( !NT_STATUS_IS_OK(status) ) {
DEBUG(3, ("Failed to check for local "
"Administrators membership (%s)\n",
nt_errstr(status)));
}
} else if (!NT_STATUS_IS_OK(status)) {
DEBUG(2, ("WARNING: Failed to create "
"BUILTIN\\Administrators group! Can "
"Winbind allocate gids?\n"));
}
}
/* Deal with the BUILTIN\Users group. If the SID can
be resolved then assume that the add_aliasmem( S-1-5-32 )
handled it. */
status = pdb_get_aliasinfo(&global_sid_Builtin_Users, info);
if (!NT_STATUS_IS_OK(status)) {
become_root();
status = create_builtin_users(domain_sid);
unbecome_root();
if (!NT_STATUS_EQUAL(status, NT_STATUS_PROTOCOL_UNREACHABLE) &&
!NT_STATUS_IS_OK(status))
{
DEBUG(2, ("WARNING: Failed to create BUILTIN\\Users group! "
"Can Winbind allocate gids?\n"));
}
}
/*
* Add BUILTIN\Guests directly to token.
* But only if the token already indicates
* real guest access by:
* - local GUEST account
* - local GUESTS group
* - domain GUESTS group
*
* Even if a user was authenticated, it
* can be member of a guest related group.
*/
status = add_builtin_guests(result, domain_sid);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(3, ("Failed to check for local "
"Guests membership (%s)\n",
nt_errstr(status)));
/*
* This is a hard error.
*/
return status;
}
TALLOC_FREE(info);
/* Deal with local groups */
if (lp_winbind_nested_groups()) {
become_root();
/* Now add the aliases. First the one from our local SAM */
status = add_aliases(get_global_sam_sid(), result);
if (!NT_STATUS_IS_OK(status)) {
unbecome_root();
return status;
}
/* Finally the builtin ones */
status = add_aliases(&global_sid_Builtin, result);
if (!NT_STATUS_IS_OK(status)) {
unbecome_root();
return status;
}
unbecome_root();
}
if (session_info_flags & AUTH_SESSION_INFO_SIMPLE_PRIVILEGES) {
if (security_token_has_builtin_administrators(result)) {
result->privilege_mask = ~0;
}
} else {
/* Add privileges based on current user sids */
get_privileges_for_sids(&result->privilege_mask, result->sids,
result->num_sids);
}
return NT_STATUS_OK;
}
/****************************************************************************
prints a UNIX 'token' to debug output.
****************************************************************************/
void debug_unix_user_token(int dbg_class, int dbg_lev, uid_t uid, gid_t gid,
int n_groups, gid_t *groups)
{
int i;
DEBUGC(dbg_class, dbg_lev,
("UNIX token of user %ld\n", (long int)uid));
DEBUGADDC(dbg_class, dbg_lev,
("Primary group is %ld and contains %i supplementary "
"groups\n", (long int)gid, n_groups));
for (i = 0; i < n_groups; i++)
DEBUGADDC(dbg_class, dbg_lev, ("Group[%3i]: %ld\n", i,
(long int)groups[i]));
}
/*
* Create an artificial NT token given just a domain SID.
*
* We have 3 cases:
*
* unmapped unix users: Go directly to nss to find the user's group.
*
* A passdb user: The list of groups is provided by pdb_enum_group_memberships.
*
* If the user is provided by winbind, the primary gid is set to "domain
* users" of the user's domain. For an explanation why this is necessary, see
* the thread starting at
* http://lists.samba.org/archive/samba-technical/2006-January/044803.html.
*/
static NTSTATUS create_token_from_sid(TALLOC_CTX *mem_ctx,
const struct dom_sid *user_sid,
bool is_guest,
uid_t *uid, gid_t *gid,
char **found_username,
struct security_token **token)
{
NTSTATUS result = NT_STATUS_NO_SUCH_USER;
TALLOC_CTX *tmp_ctx = talloc_stackframe();
gid_t *gids;
struct dom_sid *group_sids;
struct dom_sid tmp_sid;
uint32_t num_group_sids;
uint32_t num_gids;
uint32_t i;
uint32_t high, low;
bool range_ok;
if (sid_check_is_in_our_sam(user_sid)) {
bool ret;
uint32_t pdb_num_group_sids;
/* This is a passdb user, so ask passdb */
struct samu *sam_acct = NULL;
if ( !(sam_acct = samu_new( tmp_ctx )) ) {
result = NT_STATUS_NO_MEMORY;
goto done;
}
become_root();
ret = pdb_getsampwsid(sam_acct, user_sid);
unbecome_root();
if (!ret) {
DEBUG(1, ("pdb_getsampwsid(%s) failed\n",
sid_string_dbg(user_sid)));
DEBUGADD(1, ("Fall back to unix user\n"));
goto unix_user;
}
result = pdb_enum_group_memberships(tmp_ctx, sam_acct,
&group_sids, &gids,
&pdb_num_group_sids);
if (!NT_STATUS_IS_OK(result)) {
DEBUG(1, ("enum_group_memberships failed for %s: "
"%s\n", sid_string_dbg(user_sid),
nt_errstr(result)));
DEBUGADD(1, ("Fall back to unix uid lookup\n"));
goto unix_user;
}
num_group_sids = pdb_num_group_sids;
/* see the smb_panic() in pdb_default_enum_group_memberships */
SMB_ASSERT(num_group_sids > 0);
/* Ensure we're returning the found_username on the right context. */
*found_username = talloc_strdup(mem_ctx,
pdb_get_username(sam_acct));
if (*found_username == NULL) {
result = NT_STATUS_NO_MEMORY;
goto done;
}
/*
* If the SID from lookup_name() was the guest sid, passdb knows
* about the mapping of guest sid to lp_guest_account()
* username and will return the unix_pw info for a guest
* user. Use it if it's there, else lookup the *uid details
* using Get_Pwnam_alloc(). See bug #6291 for details. JRA.
*/
/* We must always assign the *uid. */
if (sam_acct->unix_pw == NULL) {
struct passwd *pwd = Get_Pwnam_alloc(sam_acct, *found_username );
if (!pwd) {
DEBUG(10, ("Get_Pwnam_alloc failed for %s\n",
*found_username));
result = NT_STATUS_NO_SUCH_USER;
goto done;
}
result = samu_set_unix(sam_acct, pwd );
if (!NT_STATUS_IS_OK(result)) {
DEBUG(10, ("samu_set_unix failed for %s\n",
*found_username));
result = NT_STATUS_NO_SUCH_USER;
goto done;
}
}
*uid = sam_acct->unix_pw->pw_uid;
} else if (sid_check_is_in_unix_users(user_sid)) {
uint32_t getgroups_num_group_sids;
/* This is a unix user not in passdb. We need to ask nss
* directly, without consulting passdb */
struct passwd *pass;
/*
* This goto target is used as a fallback for the passdb
* case. The concrete bug report is when passdb gave us an
* unmapped gid.
*/
unix_user:
if (!sid_to_uid(user_sid, uid)) {
DEBUG(1, ("unix_user case, sid_to_uid for %s failed\n",
sid_string_dbg(user_sid)));
result = NT_STATUS_NO_SUCH_USER;
goto done;
}
uid_to_unix_users_sid(*uid, &tmp_sid);
user_sid = &tmp_sid;
pass = getpwuid_alloc(tmp_ctx, *uid);
if (pass == NULL) {
DEBUG(1, ("getpwuid(%u) failed\n",
(unsigned int)*uid));
goto done;
}
if (!getgroups_unix_user(tmp_ctx, pass->pw_name, pass->pw_gid,
&gids, &getgroups_num_group_sids)) {
DEBUG(1, ("getgroups_unix_user for user %s failed\n",
pass->pw_name));
goto done;
}
num_group_sids = getgroups_num_group_sids;
group_sids = talloc_array(tmp_ctx, struct dom_sid, num_group_sids);
if (group_sids == NULL) {
DEBUG(1, ("talloc_array failed\n"));
result = NT_STATUS_NO_MEMORY;
goto done;
}
for (i=0; i<num_group_sids; i++) {
gid_to_sid(&group_sids[i], gids[i]);
}
/* In getgroups_unix_user we always set the primary gid */
SMB_ASSERT(num_group_sids > 0);
/* Ensure we're returning the found_username on the right context. */
*found_username = talloc_strdup(mem_ctx, pass->pw_name);
if (*found_username == NULL) {
result = NT_STATUS_NO_MEMORY;
goto done;
}
} else {
/* This user is from winbind, force the primary gid to the
* user's "domain users" group. Under certain circumstances
* (user comes from NT4), this might be a loss of
* information. But we can not rely on winbind getting the
* correct info. AD might prohibit winbind looking up that
* information. */
/* We must always assign the *uid. */
if (!sid_to_uid(user_sid, uid)) {
DEBUG(1, ("winbindd case, sid_to_uid for %s failed\n",
sid_string_dbg(user_sid)));
result = NT_STATUS_NO_SUCH_USER;
goto done;
}
num_group_sids = 1;
group_sids = talloc_array(tmp_ctx, struct dom_sid, num_group_sids);
if (group_sids == NULL) {
DEBUG(1, ("talloc_array failed\n"));
result = NT_STATUS_NO_MEMORY;
goto done;
}
gids = talloc_array(tmp_ctx, gid_t, num_group_sids);
if (gids == NULL) {
result = NT_STATUS_NO_MEMORY;
goto done;
}
sid_copy(&group_sids[0], user_sid);
sid_split_rid(&group_sids[0], NULL);
sid_append_rid(&group_sids[0], DOMAIN_RID_USERS);
if (!sid_to_gid(&group_sids[0], &gids[0])) {
DEBUG(1, ("sid_to_gid(%s) failed\n",
sid_string_dbg(&group_sids[0])));
goto done;
}
*found_username = NULL;
}
*gid = gids[0];
/* Add the "Unix Group" SID for each gid to catch mapped groups
and their Unix equivalent. This is to solve the backwards
compatibility problem of 'valid users = +ntadmin' where
ntadmin has been paired with "Domain Admins" in the group
mapping table. Otherwise smb.conf would need to be changed
to 'valid user = "Domain Admins"'. --jerry */
num_gids = num_group_sids;
range_ok = lp_idmap_default_range(&low, &high);
for ( i=0; i<num_gids; i++ ) {
struct dom_sid unix_group_sid;
/* don't pickup anything managed by Winbind */
if (range_ok && (gids[i] >= low) && (gids[i] <= high)) {
continue;
}
gid_to_unix_groups_sid(gids[i], &unix_group_sid);
result = add_sid_to_array_unique(tmp_ctx, &unix_group_sid,
&group_sids, &num_group_sids);
if (!NT_STATUS_IS_OK(result)) {
goto done;
}
}
/* Ensure we're creating the nt_token on the right context. */
*token = create_local_nt_token(mem_ctx, user_sid,
is_guest, num_group_sids, group_sids);
if (*token == NULL) {
result = NT_STATUS_NO_MEMORY;
goto done;
}
result = NT_STATUS_OK;
done:
TALLOC_FREE(tmp_ctx);
return result;
}
/*
* Create an artificial NT token given just a username. (Initially intended
* for force user)
*
* We go through lookup_name() to avoid problems we had with 'winbind use
* default domain'.
*
* We have 3 cases:
*
* unmapped unix users: Go directly to nss to find the user's group.
*
* A passdb user: The list of groups is provided by pdb_enum_group_memberships.
*
* If the user is provided by winbind, the primary gid is set to "domain
* users" of the user's domain. For an explanation why this is necessary, see
* the thread starting at
* http://lists.samba.org/archive/samba-technical/2006-January/044803.html.
*/
NTSTATUS create_token_from_username(TALLOC_CTX *mem_ctx, const char *username,
bool is_guest,
uid_t *uid, gid_t *gid,
char **found_username,
struct security_token **token)
{
NTSTATUS result = NT_STATUS_NO_SUCH_USER;
TALLOC_CTX *tmp_ctx = talloc_stackframe();
struct dom_sid user_sid;
enum lsa_SidType type;
if (!lookup_name_smbconf(tmp_ctx, username, LOOKUP_NAME_ALL,
NULL, NULL, &user_sid, &type)) {
DEBUG(1, ("lookup_name_smbconf for %s failed\n", username));
goto done;
}
if (type != SID_NAME_USER) {
DEBUG(1, ("%s is a %s, not a user\n", username,
sid_type_lookup(type)));
goto done;
}
result = create_token_from_sid(mem_ctx, &user_sid, is_guest, uid, gid, found_username, token);
if (!NT_STATUS_IS_OK(result)) {
goto done;
}
/*
* If result == NT_STATUS_OK then
* we know we have a valid token. Ensure
* we also have a valid username to match.
*/
if (*found_username == NULL) {
*found_username = talloc_strdup(mem_ctx, username);
if (*found_username == NULL) {
result = NT_STATUS_NO_MEMORY;
}
}
done:
TALLOC_FREE(tmp_ctx);
return result;
}
/***************************************************************************
Build upon create_token_from_sid:
Expensive helper function to figure out whether a user given its sid is
member of a particular group.
***************************************************************************/
bool user_sid_in_group_sid(const struct dom_sid *sid, const struct dom_sid *group_sid)
{
NTSTATUS status;
uid_t uid;
gid_t gid;
char *found_username;
struct security_token *token;
bool result = false;
enum lsa_SidType type;
TALLOC_CTX *mem_ctx = talloc_stackframe();
if (!lookup_sid(mem_ctx, sid,
NULL, NULL, &type)) {
DEBUG(1, ("lookup_sid for %s failed\n", dom_sid_string(mem_ctx, sid)));
goto done;
}
if (type != SID_NAME_USER) {
DEBUG(5, ("%s is a %s, not a user\n", dom_sid_string(mem_ctx, sid),
sid_type_lookup(type)));
goto done;
}
status = create_token_from_sid(mem_ctx, sid, False,
&uid, &gid, &found_username,
&token);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(10, ("could not create token for %s\n", dom_sid_string(mem_ctx, sid)));
goto done;
}
result = security_token_has_sid(token, group_sid);
done:
TALLOC_FREE(mem_ctx);
return result;
}
/***************************************************************************
Build upon create_token_from_username:
Expensive helper function to figure out whether a user given its name is
member of a particular group.
***************************************************************************/
bool user_in_group_sid(const char *username, const struct dom_sid *group_sid)
{
NTSTATUS status;
uid_t uid;
gid_t gid;
char *found_username;
struct security_token *token;
bool result;
TALLOC_CTX *mem_ctx = talloc_stackframe();
status = create_token_from_username(mem_ctx, username, False,
&uid, &gid, &found_username,
&token);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(10, ("could not create token for %s\n", username));
TALLOC_FREE(mem_ctx);
return False;
}
result = security_token_has_sid(token, group_sid);
TALLOC_FREE(mem_ctx);
return result;
}
bool user_in_group(const char *username, const char *groupname)
{
TALLOC_CTX *mem_ctx = talloc_stackframe();
struct dom_sid group_sid;
bool ret;
ret = lookup_name(mem_ctx, groupname, LOOKUP_NAME_ALL,
NULL, NULL, &group_sid, NULL);
TALLOC_FREE(mem_ctx);
if (!ret) {
DEBUG(10, ("lookup_name for (%s) failed.\n", groupname));
return False;
}
return user_in_group_sid(username, &group_sid);
}
/* END */