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token_util.c

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Last change on this file was 989, checked in by Silvan Scherrer, 9 years ago
Samba Server: update vendor to version 4.4.7
File size: 28.3 KB

Line
1	/*
2	* Unix SMB/CIFS implementation.
3	* Authentication utility functions
4	* Copyright (C) Andrew Tridgell 1992-1998
5	* Copyright (C) Andrew Bartlett 2001
6	* Copyright (C) Jeremy Allison 2000-2001
7	* Copyright (C) Rafal Szczesniak 2002
8	* Copyright (C) Volker Lendecke 2006
9	* Copyright (C) Michael Adam 2007
10	*
11	* This program is free software; you can redistribute it and/or modify
12	* it under the terms of the GNU General Public License as published by
13	* the Free Software Foundation; either version 3 of the License, or
14	* (at your option) any later version.
15	*
16	* This program is distributed in the hope that it will be useful,
17	* but WITHOUT ANY WARRANTY; without even the implied warranty of
18	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19	* GNU General Public License for more details.
20	*
21	* You should have received a copy of the GNU General Public License
22	* along with this program; if not, see <http://www.gnu.org/licenses/>.
23	*/
24
25	/* functions moved from auth/auth_util.c to minimize linker deps */
26
27	#include "includes.h"
28	#include "system/passwd.h"
29	#include "auth.h"
30	#include "secrets.h"
31	#include "../lib/util/memcache.h"
32	#include "../librpc/gen_ndr/netlogon.h"
33	#include "../libcli/security/security.h"
34	#include "../lib/util/util_pw.h"
35	#include "passdb.h"
36	#include "lib/privileges.h"
37
38	/****************************************************************************
39	Check for a SID in an struct security_token
40	****************************************************************************/
41
42	bool nt_token_check_sid ( const struct dom_sid sid, const struct security_token token )
43	{
44	if ( !sid \|\| !token )
45	return False;
46
47	return security_token_has_sid(token, sid);
48	}
49
50	bool nt_token_check_domain_rid( struct security_token *token, uint32_t rid )
51	{
52	struct dom_sid domain_sid;
53
54	/* if we are a domain member, the get the domain SID, else for
55	a DC or standalone server, use our own SID */
56
57	if ( lp_server_role() == ROLE_DOMAIN_MEMBER ) {
58	if ( !secrets_fetch_domain_sid( lp_workgroup(),
59	&domain_sid ) ) {
60	DEBUG(1,("nt_token_check_domain_rid: Cannot lookup "
61	"SID for domain [%s]\n", lp_workgroup()));
62	return False;
63	}
64	}
65	else
66	sid_copy( &domain_sid, get_global_sam_sid() );
67
68	sid_append_rid( &domain_sid, rid );
69
70	return nt_token_check_sid( &domain_sid, token );\
71	}
72
73	/******************************************************************************
74	Create a token for the root user to be used internally by smbd.
75	This is similar to running under the context of the LOCAL_SYSTEM account
76	in Windows. This is a read-only token. Do not modify it or free() it.
77	Create a copy if you need to change it.
78	******************************************************************************/
79
80	struct security_token *get_root_nt_token( void )
81	{
82	struct security_token token, for_cache;
83	struct dom_sid u_sid, g_sid;
84	struct passwd *pw;
85	void *cache_data;
86
87	cache_data = memcache_lookup_talloc(
88	NULL, SINGLETON_CACHE_TALLOC,
89	data_blob_string_const_null("root_nt_token"));
90
91	if (cache_data != NULL) {
92	return talloc_get_type_abort(
93	cache_data, struct security_token);
94	}
95
96	if ( !(pw = getpwuid(0)) ) {
97	if ( !(pw = getpwnam("root")) ) {
98	DEBUG(0,("get_root_nt_token: both getpwuid(0) "
99	"and getpwnam(\"root\") failed!\n"));
100	return NULL;
101	}
102	}
103
104	/* get the user and primary group SIDs; although the
105	BUILTIN\Administrators SId is really the one that matters here */
106
107	uid_to_sid(&u_sid, pw->pw_uid);
108	gid_to_sid(&g_sid, pw->pw_gid);
109
110	token = create_local_nt_token(talloc_tos(), &u_sid, False,
111	1, &global_sid_Builtin_Administrators);
112
113	security_token_set_privilege(token, SEC_PRIV_DISK_OPERATOR);
114
115	for_cache = token;
116
117	memcache_add_talloc(
118	NULL, SINGLETON_CACHE_TALLOC,
119	data_blob_string_const_null("root_nt_token"), &for_cache);
120
121	return token;
122	}
123
124
125	/*
126	* Add alias SIDs from memberships within the partially created token SID list
127	*/
128
129	NTSTATUS add_aliases(const struct dom_sid *domain_sid,
130	struct security_token *token)
131	{
132	uint32_t *aliases;
133	size_t i, num_aliases;
134	NTSTATUS status;
135	TALLOC_CTX *tmp_ctx;
136
137	if (!(tmp_ctx = talloc_init("add_aliases"))) {
138	return NT_STATUS_NO_MEMORY;
139	}
140
141	aliases = NULL;
142	num_aliases = 0;
143
144	status = pdb_enum_alias_memberships(tmp_ctx, domain_sid,
145	token->sids,
146	token->num_sids,
147	&aliases, &num_aliases);
148
149	if (!NT_STATUS_IS_OK(status)) {
150	DEBUG(10, ("pdb_enum_alias_memberships failed: %s\n",
151	nt_errstr(status)));
152	goto done;
153	}
154
155	for (i=0; i<num_aliases; i++) {
156	struct dom_sid alias_sid;
157	sid_compose(&alias_sid, domain_sid, aliases[i]);
158	status = add_sid_to_array_unique(token, &alias_sid,
159	&token->sids,
160	&token->num_sids);
161	if (!NT_STATUS_IS_OK(status)) {
162	DEBUG(0, ("add_sid_to_array failed\n"));
163	goto done;
164	}
165	}
166
167	done:
168	TALLOC_FREE(tmp_ctx);
169	return NT_STATUS_OK;
170	}
171
172	/*******************************************************************
173	*******************************************************************/
174
175	static NTSTATUS add_builtin_administrators(struct security_token *token,
176	const struct dom_sid *dom_sid)
177	{
178	struct dom_sid domadm;
179	NTSTATUS status;
180
181	/* nothing to do if we aren't in a domain */
182
183	if ( !(IS_DC \|\| lp_server_role()==ROLE_DOMAIN_MEMBER) ) {
184	return NT_STATUS_OK;
185	}
186
187	/* Find the Domain Admins SID */
188
189	if ( IS_DC ) {
190	sid_copy( &domadm, get_global_sam_sid() );
191	} else {
192	sid_copy(&domadm, dom_sid);
193	}
194	sid_append_rid( &domadm, DOMAIN_RID_ADMINS );
195
196	/* Add Administrators if the user beloongs to Domain Admins */
197
198	if ( nt_token_check_sid( &domadm, token ) ) {
199	status = add_sid_to_array(token,
200	&global_sid_Builtin_Administrators,
201	&token->sids, &token->num_sids);
202	if (!NT_STATUS_IS_OK(status)) {
203	return status;
204	}
205	}
206
207	return NT_STATUS_OK;
208	}
209
210	static NTSTATUS finalize_local_nt_token(struct security_token *result,
211	bool is_guest);
212
213	NTSTATUS create_local_nt_token_from_info3(TALLOC_CTX *mem_ctx,
214	bool is_guest,
215	const struct netr_SamInfo3 *info3,
216	const struct extra_auth_info *extra,
217	struct security_token **ntok)
218	{
219	struct security_token *usrtok = NULL;
220	NTSTATUS status;
221	int i;
222
223	DEBUG(10, ("Create local NT token for %s\n",
224	info3->base.account_name.string));
225
226	usrtok = talloc_zero(mem_ctx, struct security_token);
227	if (!usrtok) {
228	DEBUG(0, ("talloc failed\n"));
229	return NT_STATUS_NO_MEMORY;
230	}
231
232	/* Add the user and primary group sid FIRST */
233	/* check if the user rid is the special "Domain Guests" rid.
234	* If so pick the first sid for the extra sids instead as it
235	* is a local fake account */
236	usrtok->sids = talloc_array(usrtok, struct dom_sid, 2);
237	if (!usrtok->sids) {
238	TALLOC_FREE(usrtok);
239	return NT_STATUS_NO_MEMORY;
240	}
241	usrtok->num_sids = 2;
242
243	/* USER SID */
244	if (info3->base.rid == (uint32_t)(-1)) {
245	/* this is a signal the user was fake and generated,
246	* the actual SID we want to use is stored in the extra
247	* sids */
248	if (is_null_sid(&extra->user_sid)) {
249	/* we couldn't find the user sid, bail out */
250	DEBUG(3, ("Invalid user SID\n"));
251	TALLOC_FREE(usrtok);
252	return NT_STATUS_UNSUCCESSFUL;
253	}
254	sid_copy(&usrtok->sids[0], &extra->user_sid);
255	} else {
256	sid_copy(&usrtok->sids[0], info3->base.domain_sid);
257	sid_append_rid(&usrtok->sids[0], info3->base.rid);
258	}
259
260	/* GROUP SID */
261	if (info3->base.primary_gid == (uint32_t)(-1)) {
262	/* this is a signal the user was fake and generated,
263	* the actual SID we want to use is stored in the extra
264	* sids */
265	if (is_null_sid(&extra->pgid_sid)) {
266	/* we couldn't find the user sid, bail out */
267	DEBUG(3, ("Invalid group SID\n"));
268	TALLOC_FREE(usrtok);
269	return NT_STATUS_UNSUCCESSFUL;
270	}
271	sid_copy(&usrtok->sids[1], &extra->pgid_sid);
272	} else {
273	sid_copy(&usrtok->sids[1], info3->base.domain_sid);
274	sid_append_rid(&usrtok->sids[1],
275	info3->base.primary_gid);
276	}
277
278	/* Now the SIDs we got from authentication. These are the ones from
279	* the info3 struct or from the pdb_enum_group_memberships, depending
280	* on who authenticated the user.
281	* Note that we start the for loop at "1" here, we already added the
282	* first group sid as primary above. */
283
284	for (i = 0; i < info3->base.groups.count; i++) {
285	struct dom_sid tmp_sid;
286
287	sid_copy(&tmp_sid, info3->base.domain_sid);
288	sid_append_rid(&tmp_sid, info3->base.groups.rids[i].rid);
289
290	status = add_sid_to_array_unique(usrtok, &tmp_sid,
291	&usrtok->sids,
292	&usrtok->num_sids);
293	if (!NT_STATUS_IS_OK(status)) {
294	DEBUG(3, ("Failed to add SID to nt token\n"));
295	TALLOC_FREE(usrtok);
296	return status;
297	}
298	}
299
300	/* now also add extra sids if they are not the special user/group
301	* sids */
302	for (i = 0; i < info3->sidcount; i++) {
303	status = add_sid_to_array_unique(usrtok,
304	info3->sids[i].sid,
305	&usrtok->sids,
306	&usrtok->num_sids);
307	if (!NT_STATUS_IS_OK(status)) {
308	DEBUG(3, ("Failed to add SID to nt token\n"));
309	TALLOC_FREE(usrtok);
310	return status;
311	}
312	}
313
314	status = finalize_local_nt_token(usrtok, is_guest);
315	if (!NT_STATUS_IS_OK(status)) {
316	DEBUG(3, ("Failed to finalize nt token\n"));
317	TALLOC_FREE(usrtok);
318	return status;
319	}
320
321	*ntok = usrtok;
322	return NT_STATUS_OK;
323	}
324
325	/*******************************************************************
326	Create a NT token for the user, expanding local aliases
327	*******************************************************************/
328
329	struct security_token create_local_nt_token(TALLOC_CTX mem_ctx,
330	const struct dom_sid *user_sid,
331	bool is_guest,
332	int num_groupsids,
333	const struct dom_sid *groupsids)
334	{
335	struct security_token *result = NULL;
336	int i;
337	NTSTATUS status;
338
339	DEBUG(10, ("Create local NT token for %s\n",
340	sid_string_dbg(user_sid)));
341
342	if (!(result = talloc_zero(mem_ctx, struct security_token))) {
343	DEBUG(0, ("talloc failed\n"));
344	return NULL;
345	}
346
347	/* Add the user and primary group sid */
348
349	status = add_sid_to_array(result, user_sid,
350	&result->sids, &result->num_sids);
351	if (!NT_STATUS_IS_OK(status)) {
352	TALLOC_FREE(result);
353	return NULL;
354	}
355
356	/* For guest, num_groupsids may be zero. */
357	if (num_groupsids) {
358	status = add_sid_to_array(result, &groupsids[0],
359	&result->sids,
360	&result->num_sids);
361	if (!NT_STATUS_IS_OK(status)) {
362	TALLOC_FREE(result);
363	return NULL;
364	}
365	}
366
367	/* Now the SIDs we got from authentication. These are the ones from
368	* the info3 struct or from the pdb_enum_group_memberships, depending
369	* on who authenticated the user.
370	* Note that we start the for loop at "1" here, we already added the
371	* first group sid as primary above. */
372
373	for (i=1; i<num_groupsids; i++) {
374	status = add_sid_to_array_unique(result, &groupsids[i],
375	&result->sids,
376	&result->num_sids);
377	if (!NT_STATUS_IS_OK(status)) {
378	TALLOC_FREE(result);
379	return NULL;
380	}
381	}
382
383	status = finalize_local_nt_token(result, is_guest);
384	if (!NT_STATUS_IS_OK(status)) {
385	TALLOC_FREE(result);
386	return NULL;
387	}
388
389	return result;
390	}
391
392	/***************************************************
393	Merge in any groups from /etc/group.
394	***************************************************/
395
396	static NTSTATUS add_local_groups(struct security_token *result,
397	bool is_guest)
398	{
399	gid_t *gids = NULL;
400	uint32_t getgroups_num_group_sids = 0;
401	struct passwd *pass = NULL;
402	TALLOC_CTX *tmp_ctx = talloc_stackframe();
403	int i;
404
405	if (is_guest) {
406	/*
407	* Guest is a special case. It's always
408	* a user that can be looked up, but
409	* result->sids[0] is set to DOMAIN\Guest.
410	* Lookup by account name instead.
411	*/
412	pass = Get_Pwnam_alloc(tmp_ctx, lp_guest_account());
413	} else {
414	uid_t uid;
415
416	/* For non-guest result->sids[0] is always the user sid. */
417	if (!sid_to_uid(&result->sids[0], &uid)) {
418	/*
419	* Non-mappable SID like SYSTEM.
420	* Can't be in any /etc/group groups.
421	*/
422	TALLOC_FREE(tmp_ctx);
423	return NT_STATUS_OK;
424	}
425
426	pass = getpwuid_alloc(tmp_ctx, uid);
427	if (pass == NULL) {
428	DEBUG(1, ("SID %s -> getpwuid(%u) failed\n",
429	sid_string_dbg(&result->sids[0]),
430	(unsigned int)uid));
431	}
432	}
433
434	if (!pass) {
435	TALLOC_FREE(tmp_ctx);
436	return NT_STATUS_UNSUCCESSFUL;
437	}
438
439	/*
440	* Now we must get any groups this user has been
441	* added to in /etc/group and merge them in.
442	* This has to be done in every code path
443	* that creates an NT token, as remote users
444	* may have been added to the local /etc/group
445	* database. Tokens created merely from the
446	* info3 structs (via the DC or via the krb5 PAC)
447	* won't have these local groups. Note the
448	* groups added here will only be UNIX groups
449	* (S-1-22-2-XXXX groups) as getgroups_unix_user()
450	* turns off winbindd before calling getgroups().
451	*
452	* NB. This is duplicating work already
453	* done in the 'unix_user:' case of
454	* create_token_from_sid() but won't
455	* do anything other than be inefficient
456	* in that case.
457	*/
458
459	if (!getgroups_unix_user(tmp_ctx, pass->pw_name, pass->pw_gid,
460	&gids, &getgroups_num_group_sids)) {
461	DEBUG(1, ("getgroups_unix_user for user %s failed\n",
462	pass->pw_name));
463	TALLOC_FREE(tmp_ctx);
464	return NT_STATUS_UNSUCCESSFUL;
465	}
466
467	for (i=0; i<getgroups_num_group_sids; i++) {
468	NTSTATUS status;
469	struct dom_sid grp_sid;
470	gid_to_sid(&grp_sid, gids[i]);
471
472	status = add_sid_to_array_unique(result,
473	&grp_sid,
474	&result->sids,
475	&result->num_sids);
476	if (!NT_STATUS_IS_OK(status)) {
477	DEBUG(3, ("Failed to add UNIX SID to nt token\n"));
478	TALLOC_FREE(tmp_ctx);
479	return status;
480	}
481	}
482	TALLOC_FREE(tmp_ctx);
483	return NT_STATUS_OK;
484	}
485
486	static NTSTATUS finalize_local_nt_token(struct security_token *result,
487	bool is_guest)
488	{
489	struct dom_sid dom_sid;
490	NTSTATUS status;
491	struct acct_info *info;
492
493	/* Add any local groups. */
494
495	status = add_local_groups(result, is_guest);
496	if (!NT_STATUS_IS_OK(status)) {
497	return status;
498	}
499
500	/* Add in BUILTIN sids */
501
502	status = add_sid_to_array(result, &global_sid_World,
503	&result->sids, &result->num_sids);
504	if (!NT_STATUS_IS_OK(status)) {
505	return status;
506	}
507	status = add_sid_to_array(result, &global_sid_Network,
508	&result->sids, &result->num_sids);
509	if (!NT_STATUS_IS_OK(status)) {
510	return status;
511	}
512
513	if (is_guest) {
514	status = add_sid_to_array(result, &global_sid_Builtin_Guests,
515	&result->sids,
516	&result->num_sids);
517	if (!NT_STATUS_IS_OK(status)) {
518	return status;
519	}
520	} else {
521	status = add_sid_to_array(result,
522	&global_sid_Authenticated_Users,
523	&result->sids,
524	&result->num_sids);
525	if (!NT_STATUS_IS_OK(status)) {
526	return status;
527	}
528	}
529
530	info = talloc_zero(talloc_tos(), struct acct_info);
531	if (info == NULL) {
532	DEBUG(0, ("talloc failed!\n"));
533	return NT_STATUS_NO_MEMORY;
534	}
535
536	/* Deal with the BUILTIN\Administrators group. If the SID can
537	be resolved then assume that the add_aliasmem( S-1-5-32 )
538	handled it. */
539
540	status = pdb_get_aliasinfo(&global_sid_Builtin_Administrators, info);
541	if (!NT_STATUS_IS_OK(status)) {
542
543	become_root();
544	if (!secrets_fetch_domain_sid(lp_workgroup(), &dom_sid)) {
545	status = NT_STATUS_OK;
546	DEBUG(3, ("Failed to fetch domain sid for %s\n",
547	lp_workgroup()));
548	} else {
549	status = create_builtin_administrators(&dom_sid);
550	}
551	unbecome_root();
552
553	if (NT_STATUS_EQUAL(status, NT_STATUS_PROTOCOL_UNREACHABLE)) {
554	/* Add BUILTIN\Administrators directly to token. */
555	status = add_builtin_administrators(result, &dom_sid);
556	if ( !NT_STATUS_IS_OK(status) ) {
557	DEBUG(3, ("Failed to check for local "
558	"Administrators membership (%s)\n",
559	nt_errstr(status)));
560	}
561	} else if (!NT_STATUS_IS_OK(status)) {
562	DEBUG(2, ("WARNING: Failed to create "
563	"BUILTIN\\Administrators group! Can "
564	"Winbind allocate gids?\n"));
565	}
566	}
567
568	/* Deal with the BUILTIN\Users group. If the SID can
569	be resolved then assume that the add_aliasmem( S-1-5-32 )
570	handled it. */
571
572	status = pdb_get_aliasinfo(&global_sid_Builtin_Users, info);
573	if (!NT_STATUS_IS_OK(status)) {
574
575	become_root();
576	if (!secrets_fetch_domain_sid(lp_workgroup(), &dom_sid)) {
577	status = NT_STATUS_OK;
578	DEBUG(3, ("Failed to fetch domain sid for %s\n",
579	lp_workgroup()));
580	} else {
581	status = create_builtin_users(&dom_sid);
582	}
583	unbecome_root();
584
585	if (!NT_STATUS_EQUAL(status, NT_STATUS_PROTOCOL_UNREACHABLE) &&
586	!NT_STATUS_IS_OK(status))
587	{
588	DEBUG(2, ("WARNING: Failed to create BUILTIN\\Users group! "
589	"Can Winbind allocate gids?\n"));
590	}
591	}
592
593	TALLOC_FREE(info);
594
595	/* Deal with local groups */
596
597	if (lp_winbind_nested_groups()) {
598
599	become_root();
600
601	/* Now add the aliases. First the one from our local SAM */
602
603	status = add_aliases(get_global_sam_sid(), result);
604
605	if (!NT_STATUS_IS_OK(status)) {
606	unbecome_root();
607	return status;
608	}
609
610	/* Finally the builtin ones */
611
612	status = add_aliases(&global_sid_Builtin, result);
613
614	if (!NT_STATUS_IS_OK(status)) {
615	unbecome_root();
616	return status;
617	}
618
619	unbecome_root();
620	}
621
622	/* Add privileges based on current user sids */
623
624	get_privileges_for_sids(&result->privilege_mask, result->sids,
625	result->num_sids);
626
627	return NT_STATUS_OK;
628	}
629
630	/****************************************************************************
631	prints a UNIX 'token' to debug output.
632	****************************************************************************/
633
634	void debug_unix_user_token(int dbg_class, int dbg_lev, uid_t uid, gid_t gid,
635	int n_groups, gid_t *groups)
636	{
637	int i;
638	DEBUGC(dbg_class, dbg_lev,
639	("UNIX token of user %ld\n", (long int)uid));
640
641	DEBUGADDC(dbg_class, dbg_lev,
642	("Primary group is %ld and contains %i supplementary "
643	"groups\n", (long int)gid, n_groups));
644	for (i = 0; i < n_groups; i++)
645	DEBUGADDC(dbg_class, dbg_lev, ("Group[%3i]: %ld\n", i,
646	(long int)groups[i]));
647	}
648
649	/*
650	* Create an artificial NT token given just a domain SID.
651	*
652	* We have 3 cases:
653	*
654	* unmapped unix users: Go directly to nss to find the user's group.
655	*
656	* A passdb user: The list of groups is provided by pdb_enum_group_memberships.
657	*
658	* If the user is provided by winbind, the primary gid is set to "domain
659	* users" of the user's domain. For an explanation why this is necessary, see
660	* the thread starting at
661	* http://lists.samba.org/archive/samba-technical/2006-January/044803.html.
662	*/
663
664	static NTSTATUS create_token_from_sid(TALLOC_CTX *mem_ctx,
665	const struct dom_sid *user_sid,
666	bool is_guest,
667	uid_t uid, gid_t gid,
668	char **found_username,
669	struct security_token **token)
670	{
671	NTSTATUS result = NT_STATUS_NO_SUCH_USER;
672	TALLOC_CTX *tmp_ctx = talloc_stackframe();
673	gid_t *gids;
674	struct dom_sid *group_sids;
675	struct dom_sid tmp_sid;
676	uint32_t num_group_sids;
677	uint32_t num_gids;
678	uint32_t i;
679	uint32_t high, low;
680	bool range_ok;
681
682	if (sid_check_is_in_our_sam(user_sid)) {
683	bool ret;
684	uint32_t pdb_num_group_sids;
685	/* This is a passdb user, so ask passdb */
686
687	struct samu *sam_acct = NULL;
688
689	if ( !(sam_acct = samu_new( tmp_ctx )) ) {
690	result = NT_STATUS_NO_MEMORY;
691	goto done;
692	}
693
694	become_root();
695	ret = pdb_getsampwsid(sam_acct, user_sid);
696	unbecome_root();
697
698	if (!ret) {
699	DEBUG(1, ("pdb_getsampwsid(%s) failed\n",
700	sid_string_dbg(user_sid)));
701	DEBUGADD(1, ("Fall back to unix user\n"));
702	goto unix_user;
703	}
704
705	result = pdb_enum_group_memberships(tmp_ctx, sam_acct,
706	&group_sids, &gids,
707	&pdb_num_group_sids);
708	if (!NT_STATUS_IS_OK(result)) {
709	DEBUG(1, ("enum_group_memberships failed for %s: "
710	"%s\n", sid_string_dbg(user_sid),
711	nt_errstr(result)));
712	DEBUGADD(1, ("Fall back to unix uid lookup\n"));
713	goto unix_user;
714	}
715	num_group_sids = pdb_num_group_sids;
716
717	/* see the smb_panic() in pdb_default_enum_group_memberships */
718	SMB_ASSERT(num_group_sids > 0);
719
720	/* Ensure we're returning the found_username on the right context. */
721	*found_username = talloc_strdup(mem_ctx,
722	pdb_get_username(sam_acct));
723
724	if (*found_username == NULL) {
725	result = NT_STATUS_NO_MEMORY;
726	goto done;
727	}
728
729	/*
730	* If the SID from lookup_name() was the guest sid, passdb knows
731	* about the mapping of guest sid to lp_guest_account()
732	* username and will return the unix_pw info for a guest
733	* user. Use it if it's there, else lookup the *uid details
734	* using Get_Pwnam_alloc(). See bug #6291 for details. JRA.
735	*/
736
737	/* We must always assign the uid. /
738	if (sam_acct->unix_pw == NULL) {
739	struct passwd pwd = Get_Pwnam_alloc(sam_acct, found_username );
740	if (!pwd) {
741	DEBUG(10, ("Get_Pwnam_alloc failed for %s\n",
742	*found_username));
743	result = NT_STATUS_NO_SUCH_USER;
744	goto done;
745	}
746	result = samu_set_unix(sam_acct, pwd );
747	if (!NT_STATUS_IS_OK(result)) {
748	DEBUG(10, ("samu_set_unix failed for %s\n",
749	*found_username));
750	result = NT_STATUS_NO_SUCH_USER;
751	goto done;
752	}
753	}
754	*uid = sam_acct->unix_pw->pw_uid;
755
756	} else if (sid_check_is_in_unix_users(user_sid)) {
757	uint32_t getgroups_num_group_sids;
758	/* This is a unix user not in passdb. We need to ask nss
759	* directly, without consulting passdb */
760
761	struct passwd *pass;
762
763	/*
764	* This goto target is used as a fallback for the passdb
765	* case. The concrete bug report is when passdb gave us an
766	* unmapped gid.
767	*/
768
769	unix_user:
770
771	if (!sid_to_uid(user_sid, uid)) {
772	DEBUG(1, ("unix_user case, sid_to_uid for %s failed\n",
773	sid_string_dbg(user_sid)));
774	result = NT_STATUS_NO_SUCH_USER;
775	goto done;
776	}
777
778	uid_to_unix_users_sid(*uid, &tmp_sid);
779	user_sid = &tmp_sid;
780
781	pass = getpwuid_alloc(tmp_ctx, *uid);
782	if (pass == NULL) {
783	DEBUG(1, ("getpwuid(%u) failed\n",
784	(unsigned int)*uid));
785	goto done;
786	}
787
788	if (!getgroups_unix_user(tmp_ctx, pass->pw_name, pass->pw_gid,
789	&gids, &getgroups_num_group_sids)) {
790	DEBUG(1, ("getgroups_unix_user for user %s failed\n",
791	pass->pw_name));
792	goto done;
793	}
794	num_group_sids = getgroups_num_group_sids;
795
796	group_sids = talloc_array(tmp_ctx, struct dom_sid, num_group_sids);
797	if (group_sids == NULL) {
798	DEBUG(1, ("talloc_array failed\n"));
799	result = NT_STATUS_NO_MEMORY;
800	goto done;
801	}
802
803	for (i=0; i<num_group_sids; i++) {
804	gid_to_sid(&group_sids[i], gids[i]);
805	}
806
807	/* In getgroups_unix_user we always set the primary gid */
808	SMB_ASSERT(num_group_sids > 0);
809
810	/* Ensure we're returning the found_username on the right context. */
811	*found_username = talloc_strdup(mem_ctx, pass->pw_name);
812	if (*found_username == NULL) {
813	result = NT_STATUS_NO_MEMORY;
814	goto done;
815	}
816	} else {
817
818	/* This user is from winbind, force the primary gid to the
819	* user's "domain users" group. Under certain circumstances
820	* (user comes from NT4), this might be a loss of
821	* information. But we can not rely on winbind getting the
822	* correct info. AD might prohibit winbind looking up that
823	* information. */
824
825	/* We must always assign the uid. /
826	if (!sid_to_uid(user_sid, uid)) {
827	DEBUG(1, ("winbindd case, sid_to_uid for %s failed\n",
828	sid_string_dbg(user_sid)));
829	result = NT_STATUS_NO_SUCH_USER;
830	goto done;
831	}
832
833	num_group_sids = 1;
834	group_sids = talloc_array(tmp_ctx, struct dom_sid, num_group_sids);
835	if (group_sids == NULL) {
836	DEBUG(1, ("talloc_array failed\n"));
837	result = NT_STATUS_NO_MEMORY;
838	goto done;
839	}
840
841	gids = talloc_array(tmp_ctx, gid_t, num_group_sids);
842	if (gids == NULL) {
843	result = NT_STATUS_NO_MEMORY;
844	goto done;
845	}
846
847	sid_copy(&group_sids[0], user_sid);
848	sid_split_rid(&group_sids[0], NULL);
849	sid_append_rid(&group_sids[0], DOMAIN_RID_USERS);
850
851	if (!sid_to_gid(&group_sids[0], &gids[0])) {
852	DEBUG(1, ("sid_to_gid(%s) failed\n",
853	sid_string_dbg(&group_sids[0])));
854	goto done;
855	}
856
857	*found_username = NULL;
858	}
859
860	*gid = gids[0];
861
862	/* Add the "Unix Group" SID for each gid to catch mapped groups
863	and their Unix equivalent. This is to solve the backwards
864	compatibility problem of 'valid users = +ntadmin' where
865	ntadmin has been paired with "Domain Admins" in the group
866	mapping table. Otherwise smb.conf would need to be changed
867	to 'valid user = "Domain Admins"'. --jerry */
868
869	num_gids = num_group_sids;
870	range_ok = lp_idmap_default_range(&low, &high);
871	for ( i=0; i<num_gids; i++ ) {
872	struct dom_sid unix_group_sid;
873
874	/* don't pickup anything managed by Winbind */
875	if (range_ok && (gids[i] >= low) && (gids[i] <= high)) {
876	continue;
877	}
878
879	gid_to_unix_groups_sid(gids[i], &unix_group_sid);
880
881	result = add_sid_to_array_unique(tmp_ctx, &unix_group_sid,
882	&group_sids, &num_group_sids);
883	if (!NT_STATUS_IS_OK(result)) {
884	goto done;
885	}
886	}
887
888	/* Ensure we're creating the nt_token on the right context. */
889	*token = create_local_nt_token(mem_ctx, user_sid,
890	is_guest, num_group_sids, group_sids);
891
892	if (*token == NULL) {
893	result = NT_STATUS_NO_MEMORY;
894	goto done;
895	}
896
897	result = NT_STATUS_OK;
898	done:
899	TALLOC_FREE(tmp_ctx);
900	return result;
901	}
902
903	/*
904	* Create an artificial NT token given just a username. (Initially intended
905	* for force user)
906	*
907	* We go through lookup_name() to avoid problems we had with 'winbind use
908	* default domain'.
909	*
910	* We have 3 cases:
911	*
912	* unmapped unix users: Go directly to nss to find the user's group.
913	*
914	* A passdb user: The list of groups is provided by pdb_enum_group_memberships.
915	*
916	* If the user is provided by winbind, the primary gid is set to "domain
917	* users" of the user's domain. For an explanation why this is necessary, see
918	* the thread starting at
919	* http://lists.samba.org/archive/samba-technical/2006-January/044803.html.
920	*/
921
922	NTSTATUS create_token_from_username(TALLOC_CTX mem_ctx, const char username,
923	bool is_guest,
924	uid_t uid, gid_t gid,
925	char **found_username,
926	struct security_token **token)
927	{
928	NTSTATUS result = NT_STATUS_NO_SUCH_USER;
929	TALLOC_CTX *tmp_ctx = talloc_stackframe();
930	struct dom_sid user_sid;
931	enum lsa_SidType type;
932
933	if (!lookup_name_smbconf(tmp_ctx, username, LOOKUP_NAME_ALL,
934	NULL, NULL, &user_sid, &type)) {
935	DEBUG(1, ("lookup_name_smbconf for %s failed\n", username));
936	goto done;
937	}
938
939	if (type != SID_NAME_USER) {
940	DEBUG(1, ("%s is a %s, not a user\n", username,
941	sid_type_lookup(type)));
942	goto done;
943	}
944
945	result = create_token_from_sid(mem_ctx, &user_sid, is_guest, uid, gid, found_username, token);
946
947	if (!NT_STATUS_IS_OK(result)) {
948	goto done;
949	}
950
951	/*
952	* If result == NT_STATUS_OK then
953	* we know we have a valid token. Ensure
954	* we also have a valid username to match.
955	*/
956
957	if (*found_username == NULL) {
958	*found_username = talloc_strdup(mem_ctx, username);
959	if (*found_username == NULL) {
960	result = NT_STATUS_NO_MEMORY;
961	}
962	}
963
964	done:
965	TALLOC_FREE(tmp_ctx);
966	return result;
967	}
968
969	/***************************************************************************
970	Build upon create_token_from_sid:
971
972	Expensive helper function to figure out whether a user given its sid is
973	member of a particular group.
974	***************************************************************************/
975
976	bool user_sid_in_group_sid(const struct dom_sid sid, const struct dom_sid group_sid)
977	{
978	NTSTATUS status;
979	uid_t uid;
980	gid_t gid;
981	char *found_username;
982	struct security_token *token;
983	bool result = false;
984	enum lsa_SidType type;
985	TALLOC_CTX *mem_ctx = talloc_stackframe();
986
987	if (!lookup_sid(mem_ctx, sid,
988	NULL, NULL, &type)) {
989	DEBUG(1, ("lookup_sid for %s failed\n", dom_sid_string(mem_ctx, sid)));
990	goto done;
991	}
992
993	if (type != SID_NAME_USER) {
994	DEBUG(5, ("%s is a %s, not a user\n", dom_sid_string(mem_ctx, sid),
995	sid_type_lookup(type)));
996	goto done;
997	}
998
999	status = create_token_from_sid(mem_ctx, sid, False,
1000	&uid, &gid, &found_username,
1001	&token);
1002
1003	if (!NT_STATUS_IS_OK(status)) {
1004	DEBUG(10, ("could not create token for %s\n", dom_sid_string(mem_ctx, sid)));
1005	goto done;
1006	}
1007
1008	result = security_token_has_sid(token, group_sid);
1009
1010	done:
1011	TALLOC_FREE(mem_ctx);
1012	return result;
1013	}
1014
1015	/***************************************************************************
1016	Build upon create_token_from_username:
1017
1018	Expensive helper function to figure out whether a user given its name is
1019	member of a particular group.
1020	***************************************************************************/
1021
1022	bool user_in_group_sid(const char username, const struct dom_sid group_sid)
1023	{
1024	NTSTATUS status;
1025	uid_t uid;
1026	gid_t gid;
1027	char *found_username;
1028	struct security_token *token;
1029	bool result;
1030	TALLOC_CTX *mem_ctx = talloc_stackframe();
1031
1032	status = create_token_from_username(mem_ctx, username, False,
1033	&uid, &gid, &found_username,
1034	&token);
1035
1036	if (!NT_STATUS_IS_OK(status)) {
1037	DEBUG(10, ("could not create token for %s\n", username));
1038	TALLOC_FREE(mem_ctx);
1039	return False;
1040	}
1041
1042	result = security_token_has_sid(token, group_sid);
1043
1044	TALLOC_FREE(mem_ctx);
1045	return result;
1046	}
1047
1048	bool user_in_group(const char username, const char groupname)
1049	{
1050	TALLOC_CTX *mem_ctx = talloc_stackframe();
1051	struct dom_sid group_sid;
1052	bool ret;
1053
1054	ret = lookup_name(mem_ctx, groupname, LOOKUP_NAME_ALL,
1055	NULL, NULL, &group_sid, NULL);
1056	TALLOC_FREE(mem_ctx);
1057
1058	if (!ret) {
1059	DEBUG(10, ("lookup_name for (%s) failed.\n", groupname));
1060	return False;
1061	}
1062
1063	return user_in_group_sid(username, &group_sid);
1064	}
1065
1066	/* END */

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source: vendor/current/source3/auth/token_util.c

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