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auth: Provide a way to use the auth stack for winbindd authentication
[Samba/wip.git] / source3 / auth / token_util.c
blob8b0174fc44cbf73f6df2eb165d99bd9320e8f3a5
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 "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 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 *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 unix_group_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 *gid = gids[0];
721
722 /* Ensure we're returning the found_username on the right context. */
723 *found_username = talloc_strdup(mem_ctx,
724 pdb_get_username(sam_acct));
725
726 if (*found_username == NULL) {
727 result = NT_STATUS_NO_MEMORY;
728 goto done;
729 }
730
731 /*
732 * If the SID from lookup_name() was the guest sid, passdb knows
733 * about the mapping of guest sid to lp_guest_account()
734 * username and will return the unix_pw info for a guest
735 * user. Use it if it's there, else lookup the *uid details
736 * using Get_Pwnam_alloc(). See bug #6291 for details. JRA.
737 */
738
739 /* We must always assign the *uid. */
740 if (sam_acct->unix_pw == NULL) {
741 struct passwd *pwd = Get_Pwnam_alloc(sam_acct, *found_username );
742 if (!pwd) {
743 DEBUG(10, ("Get_Pwnam_alloc failed for %s\n",
744 *found_username));
745 result = NT_STATUS_NO_SUCH_USER;
746 goto done;
747 }
748 result = samu_set_unix(sam_acct, pwd );
749 if (!NT_STATUS_IS_OK(result)) {
750 DEBUG(10, ("samu_set_unix failed for %s\n",
751 *found_username));
752 result = NT_STATUS_NO_SUCH_USER;
753 goto done;
754 }
755 }
756 *uid = sam_acct->unix_pw->pw_uid;
757
758 } else if (sid_check_is_in_unix_users(user_sid)) {
759 struct dom_sid tmp_sid;
760 uint32_t getgroups_num_group_sids;
761 /* This is a unix user not in passdb. We need to ask nss
762 * directly, without consulting passdb */
763
764 struct passwd *pass;
765
766 /*
767 * This goto target is used as a fallback for the passdb
768 * case. The concrete bug report is when passdb gave us an
769 * unmapped gid.
770 */
771
772 unix_user:
773
774 if (!sid_to_uid(user_sid, uid)) {
775 DEBUG(1, ("unix_user case, sid_to_uid for %s failed\n",
776 sid_string_dbg(user_sid)));
777 result = NT_STATUS_NO_SUCH_USER;
778 goto done;
779 }
780
781 uid_to_unix_users_sid(*uid, &tmp_sid);
782 user_sid = &tmp_sid;
783
784 pass = getpwuid_alloc(tmp_ctx, *uid);
785 if (pass == NULL) {
786 DEBUG(1, ("getpwuid(%u) failed\n",
787 (unsigned int)*uid));
788 goto done;
789 }
790
791 if (!getgroups_unix_user(tmp_ctx, pass->pw_name, pass->pw_gid,
792 &gids, &getgroups_num_group_sids)) {
793 DEBUG(1, ("getgroups_unix_user for user %s failed\n",
794 pass->pw_name));
795 goto done;
796 }
797 num_group_sids = getgroups_num_group_sids;
798
799 if (num_group_sids) {
800 group_sids = talloc_array(tmp_ctx, struct dom_sid, num_group_sids);
801 if (group_sids == NULL) {
802 DEBUG(1, ("talloc_array failed\n"));
803 result = NT_STATUS_NO_MEMORY;
804 goto done;
805 }
806 } else {
807 group_sids = NULL;
808 }
809
810 for (i=0; i<num_group_sids; i++) {
811 gid_to_sid(&group_sids[i], gids[i]);
812 }
813
814 /* In getgroups_unix_user we always set the primary gid */
815 SMB_ASSERT(num_group_sids > 0);
816
817 *gid = gids[0];
818
819 /* Ensure we're returning the found_username on the right context. */
820 *found_username = talloc_strdup(mem_ctx, pass->pw_name);
821 if (*found_username == NULL) {
822 result = NT_STATUS_NO_MEMORY;
823 goto done;
824 }
825 } else {
826
827 /* This user is from winbind, force the primary gid to the
828 * user's "domain users" group. Under certain circumstances
829 * (user comes from NT4), this might be a loss of
830 * information. But we can not rely on winbind getting the
831 * correct info. AD might prohibit winbind looking up that
832 * information. */
833
834 /* We must always assign the *uid. */
835 if (!sid_to_uid(user_sid, uid)) {
836 DEBUG(1, ("winbindd case, sid_to_uid for %s failed\n",
837 sid_string_dbg(user_sid)));
838 result = NT_STATUS_NO_SUCH_USER;
839 goto done;
840 }
841
842 num_group_sids = 1;
843 group_sids = talloc_array(tmp_ctx, struct dom_sid, num_group_sids);
844 if (group_sids == NULL) {
845 DEBUG(1, ("talloc_array failed\n"));
846 result = NT_STATUS_NO_MEMORY;
847 goto done;
848 }
849
850 sid_copy(&group_sids[0], user_sid);
851 sid_split_rid(&group_sids[0], NULL);
852 sid_append_rid(&group_sids[0], DOMAIN_RID_USERS);
853
854 if (!sid_to_gid(&group_sids[0], gid)) {
855 DEBUG(1, ("sid_to_gid(%s) failed\n",
856 sid_string_dbg(&group_sids[0])));
857 goto done;
858 }
859
860 gids = gid;
861
862 *found_username = NULL;
863 }
864
865 /* Add the "Unix Group" SID for each gid to catch mapped groups
866 and their Unix equivalent. This is to solve the backwards
867 compatibility problem of 'valid users = +ntadmin' where
868 ntadmin has been paired with "Domain Admins" in the group
869 mapping table. Otherwise smb.conf would need to be changed
870 to 'valid user = "Domain Admins"'. --jerry */
871
872 num_gids = num_group_sids;
873 range_ok = lp_idmap_default_range(&low, &high);
874 for ( i=0; i<num_gids; i++ ) {
875
876 /* don't pickup anything managed by Winbind */
877 if (range_ok && (gids[i] >= low) && (gids[i] <= high)) {
878 continue;
879 }
880
881 gid_to_unix_groups_sid(gids[i], &unix_group_sid);
882
883 result = add_sid_to_array_unique(tmp_ctx, &unix_group_sid,
884 &group_sids, &num_group_sids);
885 if (!NT_STATUS_IS_OK(result)) {
886 goto done;
887 }
888 }
889
890 /* Ensure we're creating the nt_token on the right context. */
891 *token = create_local_nt_token(mem_ctx, user_sid,
892 is_guest, num_group_sids, group_sids);
893
894 if (*token == NULL) {
895 result = NT_STATUS_NO_MEMORY;
896 goto done;
897 }
898
899 result = NT_STATUS_OK;
900 done:
901 TALLOC_FREE(tmp_ctx);
902 return result;
903 }
904
905 /*
906 * Create an artificial NT token given just a username. (Initially intended
907 * for force user)
908 *
909 * We go through lookup_name() to avoid problems we had with 'winbind use
910 * default domain'.
911 *
912 * We have 3 cases:
913 *
914 * unmapped unix users: Go directly to nss to find the user's group.
915 *
916 * A passdb user: The list of groups is provided by pdb_enum_group_memberships.
917 *
918 * If the user is provided by winbind, the primary gid is set to "domain
919 * users" of the user's domain. For an explanation why this is necessary, see
920 * the thread starting at
921 * http://lists.samba.org/archive/samba-technical/2006-January/044803.html.
922 */
923
924 NTSTATUS create_token_from_username(TALLOC_CTX *mem_ctx, const char *username,
925 bool is_guest,
926 uid_t *uid, gid_t *gid,
927 char **found_username,
928 struct security_token **token)
929 {
930 NTSTATUS result = NT_STATUS_NO_SUCH_USER;
931 TALLOC_CTX *tmp_ctx = talloc_stackframe();
932 struct dom_sid user_sid;
933 enum lsa_SidType type;
934
935 if (!lookup_name_smbconf(tmp_ctx, username, LOOKUP_NAME_ALL,
936 NULL, NULL, &user_sid, &type)) {
937 DEBUG(1, ("lookup_name_smbconf for %s failed\n", username));
938 goto done;
939 }
940
941 if (type != SID_NAME_USER) {
942 DEBUG(1, ("%s is a %s, not a user\n", username,
943 sid_type_lookup(type)));
944 goto done;
945 }
946
947 result = create_token_from_sid(mem_ctx, &user_sid, is_guest, uid, gid, found_username, token);
948
949 if (!NT_STATUS_IS_OK(result)) {
950 goto done;
951 }
952
953 /*
954 * If result == NT_STATUS_OK then
955 * we know we have a valid token. Ensure
956 * we also have a valid username to match.
957 */
958
959 if (*found_username == NULL) {
960 *found_username = talloc_strdup(mem_ctx, username);
961 if (*found_username == NULL) {
962 result = NT_STATUS_NO_MEMORY;
963 }
964 }
965
966 done:
967 TALLOC_FREE(tmp_ctx);
968 return result;
969 }
970
971 /***************************************************************************
972 Build upon create_token_from_sid:
973
974 Expensive helper function to figure out whether a user given its sid is
975 member of a particular group.
976 ***************************************************************************/
977
978 bool user_sid_in_group_sid(const struct dom_sid *sid, const struct dom_sid *group_sid)
979 {
980 NTSTATUS status;
981 uid_t uid;
982 gid_t gid;
983 char *found_username;
984 struct security_token *token;
985 bool result = false;
986 enum lsa_SidType type;
987 TALLOC_CTX *mem_ctx = talloc_stackframe();
988
989 if (!lookup_sid(mem_ctx, sid,
990 NULL, NULL, &type)) {
991 DEBUG(1, ("lookup_sid for %s failed\n", dom_sid_string(mem_ctx, sid)));
992 goto done;
993 }
994
995 if (type != SID_NAME_USER) {
996 DEBUG(5, ("%s is a %s, not a user\n", dom_sid_string(mem_ctx, sid),
997 sid_type_lookup(type)));
998 goto done;
999 }
1000
1001 status = create_token_from_sid(mem_ctx, sid, False,
1002 &uid, &gid, &found_username,
1003 &token);
1004
1005 if (!NT_STATUS_IS_OK(status)) {
1006 DEBUG(10, ("could not create token for %s\n", dom_sid_string(mem_ctx, sid)));
1007 goto done;
1008 }
1009
1010 result = security_token_has_sid(token, group_sid);
1011
1012 done:
1013 TALLOC_FREE(mem_ctx);
1014 return result;
1015 }
1016
1017 /***************************************************************************
1018 Build upon create_token_from_username:
1019
1020 Expensive helper function to figure out whether a user given its name is
1021 member of a particular group.
1022 ***************************************************************************/
1023
1024 bool user_in_group_sid(const char *username, const struct dom_sid *group_sid)
1025 {
1026 NTSTATUS status;
1027 uid_t uid;
1028 gid_t gid;
1029 char *found_username;
1030 struct security_token *token;
1031 bool result;
1032 TALLOC_CTX *mem_ctx = talloc_stackframe();
1033
1034 status = create_token_from_username(mem_ctx, username, False,
1035 &uid, &gid, &found_username,
1036 &token);
1037
1038 if (!NT_STATUS_IS_OK(status)) {
1039 DEBUG(10, ("could not create token for %s\n", username));
1040 TALLOC_FREE(mem_ctx);
1041 return False;
1042 }
1043
1044 result = security_token_has_sid(token, group_sid);
1045
1046 TALLOC_FREE(mem_ctx);
1047 return result;
1048 }
1049
1050 bool user_in_group(const char *username, const char *groupname)
1051 {
1052 TALLOC_CTX *mem_ctx = talloc_stackframe();
1053 struct dom_sid group_sid;
1054 bool ret;
1055
1056 ret = lookup_name(mem_ctx, groupname, LOOKUP_NAME_ALL,
1057 NULL, NULL, &group_sid, NULL);
1058 TALLOC_FREE(mem_ctx);
1059
1060 if (!ret) {
1061 DEBUG(10, ("lookup_name for (%s) failed.\n", groupname));
1062 return False;
1063 }
1064
1065 return user_in_group_sid(username, &group_sid);
1066 }
1067
1068 /* END */
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