Line data Source code
1 : /*
2 : * Unix SMB/Netbios implementation.
3 : * SEC_DESC handling functions
4 : * Copyright (C) Jeremy R. Allison 1995-2003.
5 : *
6 : * This program is free software; you can redistribute it and/or modify
7 : * it under the terms of the GNU General Public License as published by
8 : * the Free Software Foundation; either version 3 of the License, or
9 : * (at your option) any later version.
10 : *
11 : * This program is distributed in the hope that it will be useful,
12 : * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 : * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 : * GNU General Public License for more details.
15 : *
16 : * You should have received a copy of the GNU General Public License
17 : * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 : */
19 :
20 : #include "includes.h"
21 : #include "system/filesys.h"
22 : #include "../libcli/security/security.h"
23 : #include "../librpc/gen_ndr/ndr_security.h"
24 : #include "dbwrap/dbwrap.h"
25 : #include "dbwrap/dbwrap_open.h"
26 : #include "util_tdb.h"
27 : #include "libcli/util/ntstatus.h"
28 :
29 : /*******************************************************************
30 : Create the share security tdb.
31 : ********************************************************************/
32 :
33 : static struct db_context *share_db; /* used for share security descriptors */
34 : #define SHARE_DATABASE_VERSION_V1 1
35 : #define SHARE_DATABASE_VERSION_V2 2 /* version id in little endian. */
36 : #define SHARE_DATABASE_VERSION_V3 3 /* canonicalized sharenames as lower case */
37 :
38 : #define SHARE_SECURITY_DB_KEY_PREFIX_STR "SECDESC/"
39 : /* Map generic permissions to file object specific permissions */
40 :
41 : extern const struct generic_mapping file_generic_mapping;
42 :
43 0 : static int delete_fn(struct db_record *rec, void *priv)
44 : {
45 0 : dbwrap_record_delete(rec);
46 0 : return 0;
47 : }
48 :
49 : /*****************************************************
50 : Looking for keys of the form: SHARE_SECURITY_DB_KEY_PREFIX_STR + "non lower case str".
51 : If we find one re-write it into a canonical case form.
52 : *****************************************************/
53 :
54 87 : static int upgrade_v2_to_v3(struct db_record *rec, void *priv)
55 : {
56 87 : size_t prefix_len = strlen(SHARE_SECURITY_DB_KEY_PREFIX_STR);
57 87 : const char *servicename = NULL;
58 87 : char *c_servicename = NULL;
59 87 : char *newkey = NULL;
60 87 : bool *p_upgrade_ok = (bool *)priv;
61 5 : NTSTATUS status;
62 5 : TDB_DATA key;
63 5 : TDB_DATA value;
64 :
65 87 : key = dbwrap_record_get_key(rec);
66 :
67 : /* Is there space for a one character sharename ? */
68 87 : if (key.dsize <= prefix_len+2) {
69 0 : return 0;
70 : }
71 :
72 : /* Does it start with the share key prefix ? */
73 87 : if (memcmp(key.dptr, SHARE_SECURITY_DB_KEY_PREFIX_STR,
74 : prefix_len) != 0) {
75 82 : return 0;
76 : }
77 :
78 : /* Is it a null terminated string as a key ? */
79 0 : if (key.dptr[key.dsize-1] != '\0') {
80 0 : return 0;
81 : }
82 :
83 : /* Bytes after the prefix are the sharename string. */
84 0 : servicename = (char *)&key.dptr[prefix_len];
85 0 : c_servicename = canonicalize_servicename(talloc_tos(), servicename);
86 0 : if (!c_servicename) {
87 0 : smb_panic("out of memory upgrading share security db from v2 -> v3");
88 : }
89 :
90 0 : if (strcmp(servicename, c_servicename) == 0) {
91 : /* Old and new names match. No canonicalization needed. */
92 0 : TALLOC_FREE(c_servicename);
93 0 : return 0;
94 : }
95 :
96 : /* Oops. Need to canonicalize name, delete old then store new. */
97 0 : status = dbwrap_record_delete(rec);
98 0 : if (!NT_STATUS_IS_OK(status)) {
99 0 : DEBUG(1, ("upgrade_v2_to_v3: Failed to delete secdesc for "
100 : "%s: %s\n", (const char *)key.dptr,
101 : nt_errstr(status)));
102 0 : TALLOC_FREE(c_servicename);
103 0 : *p_upgrade_ok = false;
104 0 : return -1;
105 : } else {
106 0 : DEBUG(10, ("upgrade_v2_to_v3: deleted secdesc for "
107 : "%s\n", (const char *)key.dptr));
108 : }
109 :
110 0 : if (!(newkey = talloc_asprintf(talloc_tos(),
111 : SHARE_SECURITY_DB_KEY_PREFIX_STR "%s",
112 : c_servicename))) {
113 0 : smb_panic("out of memory upgrading share security db from v2 -> v3");
114 : }
115 :
116 0 : value = dbwrap_record_get_value(rec);
117 0 : status = dbwrap_store(share_db,
118 : string_term_tdb_data(newkey),
119 : value,
120 : TDB_REPLACE);
121 :
122 0 : if (!NT_STATUS_IS_OK(status)) {
123 0 : DEBUG(1, ("upgrade_v2_to_v3: Failed to store secdesc for "
124 : "%s: %s\n", c_servicename, nt_errstr(status)));
125 0 : TALLOC_FREE(c_servicename);
126 0 : TALLOC_FREE(newkey);
127 0 : *p_upgrade_ok = false;
128 0 : return -1;
129 : } else {
130 0 : DEBUG(10, ("upgrade_v2_to_v3: stored secdesc for "
131 : "%s\n", newkey ));
132 : }
133 :
134 0 : TALLOC_FREE(newkey);
135 0 : TALLOC_FREE(c_servicename);
136 :
137 0 : return 0;
138 : }
139 :
140 107118 : NTSTATUS share_info_db_init(void)
141 : {
142 107118 : const char *vstring = "INFO/version";
143 107118 : int32_t vers_id = 0;
144 107118 : bool upgrade_ok = true;
145 1657 : NTSTATUS status;
146 1657 : char *db_path;
147 :
148 107118 : if (share_db != NULL) {
149 106701 : return NT_STATUS_OK;
150 : }
151 :
152 417 : db_path = state_path(talloc_tos(), "share_info.tdb");
153 417 : if (db_path == NULL) {
154 0 : return NT_STATUS_NO_MEMORY;
155 : }
156 :
157 417 : share_db = db_open(NULL, db_path, 0,
158 : TDB_DEFAULT, O_RDWR|O_CREAT, 0600,
159 : DBWRAP_LOCK_ORDER_1, DBWRAP_FLAG_NONE);
160 417 : if (share_db == NULL) {
161 0 : DEBUG(0,("Failed to open share info database %s (%s)\n",
162 : db_path, strerror(errno)));
163 0 : TALLOC_FREE(db_path);
164 0 : return map_nt_error_from_unix_common(errno);
165 : }
166 417 : TALLOC_FREE(db_path);
167 :
168 417 : status = dbwrap_fetch_int32_bystring(share_db, vstring, &vers_id);
169 417 : if (!NT_STATUS_IS_OK(status)) {
170 87 : vers_id = 0;
171 : }
172 :
173 417 : if (vers_id == SHARE_DATABASE_VERSION_V3) {
174 330 : return NT_STATUS_OK;
175 : }
176 :
177 87 : if (dbwrap_transaction_start(share_db) != 0) {
178 0 : DEBUG(0, ("transaction_start failed\n"));
179 0 : TALLOC_FREE(share_db);
180 0 : return NT_STATUS_INTERNAL_DB_ERROR;
181 : }
182 :
183 87 : status = dbwrap_fetch_int32_bystring(share_db, vstring, &vers_id);
184 87 : if (!NT_STATUS_IS_OK(status)) {
185 87 : vers_id = 0;
186 : }
187 :
188 87 : if (vers_id == SHARE_DATABASE_VERSION_V3) {
189 : /*
190 : * Race condition
191 : */
192 0 : if (dbwrap_transaction_cancel(share_db)) {
193 0 : smb_panic("transaction_cancel failed");
194 : }
195 0 : return NT_STATUS_OK;
196 : }
197 :
198 : /* Move to at least V2. */
199 :
200 : /* Cope with byte-reversed older versions of the db. */
201 87 : if ((vers_id == SHARE_DATABASE_VERSION_V1) || (IREV(vers_id) == SHARE_DATABASE_VERSION_V1)) {
202 : /* Written on a bigendian machine with old fetch_int code. Save as le. */
203 :
204 0 : status = dbwrap_store_int32_bystring(
205 : share_db, vstring, SHARE_DATABASE_VERSION_V2);
206 0 : if (!NT_STATUS_IS_OK(status)) {
207 0 : DEBUG(0, ("dbwrap_store_int32 failed: %s\n",
208 : nt_errstr(status)));
209 0 : goto cancel;
210 : }
211 0 : vers_id = SHARE_DATABASE_VERSION_V2;
212 : }
213 :
214 87 : if (vers_id != SHARE_DATABASE_VERSION_V2) {
215 87 : status = dbwrap_traverse(share_db, delete_fn, NULL, NULL);
216 87 : if (!NT_STATUS_IS_OK(status)) {
217 0 : DEBUG(0, ("traverse failed\n"));
218 0 : goto cancel;
219 : }
220 87 : status = dbwrap_store_int32_bystring(
221 : share_db, vstring, SHARE_DATABASE_VERSION_V2);
222 87 : if (!NT_STATUS_IS_OK(status)) {
223 0 : DEBUG(0, ("dbwrap_store_int32 failed: %s\n",
224 : nt_errstr(status)));
225 0 : goto cancel;
226 : }
227 : }
228 :
229 : /* Finally upgrade to version 3, with canonicalized sharenames. */
230 :
231 87 : status = dbwrap_traverse(share_db, upgrade_v2_to_v3, &upgrade_ok, NULL);
232 87 : if (!NT_STATUS_IS_OK(status)) {
233 0 : DEBUG(0, ("traverse failed\n"));
234 0 : goto cancel;
235 : }
236 87 : if (!upgrade_ok) {
237 0 : DBG_ERR("upgrade failed.\n");
238 0 : status = NT_STATUS_INTERNAL_ERROR;
239 0 : goto cancel;
240 : }
241 :
242 87 : status = dbwrap_store_int32_bystring(
243 : share_db, vstring, SHARE_DATABASE_VERSION_V3);
244 87 : if (!NT_STATUS_IS_OK(status)) {
245 0 : DEBUG(0, ("dbwrap_store_int32 failed: %s\n",
246 : nt_errstr(status)));
247 0 : goto cancel;
248 : }
249 :
250 87 : if (dbwrap_transaction_commit(share_db) != 0) {
251 0 : DEBUG(0, ("transaction_commit failed\n"));
252 0 : return NT_STATUS_INTERNAL_ERROR;
253 : }
254 :
255 87 : return NT_STATUS_OK;
256 :
257 0 : cancel:
258 0 : if (dbwrap_transaction_cancel(share_db)) {
259 0 : smb_panic("transaction_cancel failed");
260 : }
261 :
262 0 : return status;
263 : }
264 :
265 : /*******************************************************************
266 : Fake up a Everyone, default access as a default.
267 : def_access is a GENERIC_XXX access mode.
268 : ********************************************************************/
269 :
270 106370 : static struct security_descriptor *get_share_security_default(TALLOC_CTX *ctx,
271 : size_t *psize,
272 : uint32_t def_access)
273 : {
274 1657 : uint32_t sa;
275 1657 : struct security_ace ace;
276 106370 : struct security_acl *psa = NULL;
277 106370 : struct security_descriptor *psd = NULL;
278 106370 : uint32_t spec_access = def_access;
279 :
280 106370 : se_map_generic(&spec_access, &file_generic_mapping);
281 :
282 106370 : sa = (def_access | spec_access );
283 106370 : init_sec_ace(&ace, &global_sid_World, SEC_ACE_TYPE_ACCESS_ALLOWED, sa, 0);
284 :
285 106370 : if ((psa = make_sec_acl(ctx, NT4_ACL_REVISION, 1, &ace)) != NULL) {
286 106370 : psd = make_sec_desc(ctx, SECURITY_DESCRIPTOR_REVISION_1,
287 : SEC_DESC_SELF_RELATIVE, NULL, NULL, NULL,
288 : psa, psize);
289 : }
290 :
291 106370 : if (!psd) {
292 0 : DEBUG(0,("get_share_security: Failed to make SEC_DESC.\n"));
293 0 : return NULL;
294 : }
295 :
296 104713 : return psd;
297 : }
298 :
299 : /*******************************************************************
300 : Pull a security descriptor from the share tdb.
301 : ********************************************************************/
302 :
303 106926 : struct security_descriptor *get_share_security( TALLOC_CTX *ctx, const char *servicename,
304 : size_t *psize)
305 : {
306 1657 : char *key;
307 106926 : struct security_descriptor *psd = NULL;
308 1657 : TDB_DATA data;
309 106926 : char *c_servicename = canonicalize_servicename(talloc_tos(), servicename);
310 1657 : NTSTATUS status;
311 :
312 106926 : if (!c_servicename) {
313 0 : return NULL;
314 : }
315 :
316 106926 : status = share_info_db_init();
317 106926 : if (!NT_STATUS_IS_OK(status)) {
318 0 : TALLOC_FREE(c_servicename);
319 0 : return NULL;
320 : }
321 :
322 106926 : if (!(key = talloc_asprintf(ctx, SHARE_SECURITY_DB_KEY_PREFIX_STR "%s", c_servicename))) {
323 0 : TALLOC_FREE(c_servicename);
324 0 : DEBUG(0, ("talloc_asprintf failed\n"));
325 0 : return NULL;
326 : }
327 :
328 106926 : TALLOC_FREE(c_servicename);
329 :
330 106926 : status = dbwrap_fetch_bystring(share_db, talloc_tos(), key, &data);
331 :
332 106926 : TALLOC_FREE(key);
333 :
334 106926 : if (!NT_STATUS_IS_OK(status)) {
335 106370 : return get_share_security_default(ctx, psize,
336 : SEC_RIGHTS_DIR_ALL);
337 : }
338 :
339 556 : status = unmarshall_sec_desc(ctx, data.dptr, data.dsize, &psd);
340 :
341 556 : TALLOC_FREE(data.dptr);
342 :
343 556 : if (!NT_STATUS_IS_OK(status)) {
344 0 : return get_share_security_default(ctx, psize,
345 : SEC_RIGHTS_DIR_ALL);
346 : }
347 :
348 556 : if (psd) {
349 556 : *psize = ndr_size_security_descriptor(psd, 0);
350 : } else {
351 0 : return get_share_security_default(ctx, psize,
352 : SEC_RIGHTS_DIR_ALL);
353 : }
354 :
355 556 : return psd;
356 : }
357 :
358 : /*******************************************************************
359 : Store a security descriptor in the share db.
360 : ********************************************************************/
361 :
362 64 : NTSTATUS set_share_security(const char *share_name,
363 : struct security_descriptor *psd)
364 : {
365 64 : TALLOC_CTX *frame = talloc_stackframe();
366 0 : char *key;
367 0 : TDB_DATA blob;
368 0 : NTSTATUS status;
369 64 : char *c_share_name = canonicalize_servicename(frame, share_name);
370 :
371 64 : if (c_share_name == NULL) {
372 0 : status = NT_STATUS_INVALID_PARAMETER;
373 0 : goto out;
374 : }
375 :
376 64 : status = share_info_db_init();
377 64 : if (!NT_STATUS_IS_OK(status)) {
378 0 : goto out;
379 : }
380 :
381 64 : status = marshall_sec_desc(frame, psd, &blob.dptr, &blob.dsize);
382 :
383 64 : if (!NT_STATUS_IS_OK(status)) {
384 0 : DEBUG(0, ("marshall_sec_desc failed: %s\n",
385 : nt_errstr(status)));
386 0 : goto out;
387 : }
388 :
389 64 : if (!(key = talloc_asprintf(frame, SHARE_SECURITY_DB_KEY_PREFIX_STR "%s", c_share_name))) {
390 0 : DEBUG(0, ("talloc_asprintf failed\n"));
391 0 : status = NT_STATUS_NO_MEMORY;
392 0 : goto out;
393 : }
394 :
395 64 : status = dbwrap_trans_store(share_db, string_term_tdb_data(key), blob,
396 : TDB_REPLACE);
397 64 : if (!NT_STATUS_IS_OK(status)) {
398 0 : DEBUG(1, ("set_share_security: Failed to store secdesc for "
399 : "%s: %s\n", share_name, nt_errstr(status)));
400 0 : goto out;
401 : }
402 :
403 64 : DEBUG(5,("set_share_security: stored secdesc for %s\n", share_name ));
404 64 : status = NT_STATUS_OK;
405 :
406 64 : out:
407 64 : TALLOC_FREE(frame);
408 64 : return status;
409 : }
410 :
411 : /*******************************************************************
412 : Delete a security descriptor.
413 : ********************************************************************/
414 :
415 10 : NTSTATUS delete_share_security(const char *servicename)
416 : {
417 0 : TDB_DATA kbuf;
418 0 : char *key;
419 0 : NTSTATUS status;
420 10 : char *c_servicename = canonicalize_servicename(talloc_tos(), servicename);
421 :
422 10 : if (c_servicename == NULL) {
423 0 : return NT_STATUS_INVALID_PARAMETER;
424 : }
425 :
426 10 : status = share_info_db_init();
427 10 : if (!NT_STATUS_IS_OK(status)) {
428 0 : TALLOC_FREE(c_servicename);
429 0 : return status;
430 : }
431 :
432 10 : if (!(key = talloc_asprintf(talloc_tos(), SHARE_SECURITY_DB_KEY_PREFIX_STR "%s",
433 : c_servicename))) {
434 0 : TALLOC_FREE(c_servicename);
435 0 : return NT_STATUS_NO_MEMORY;
436 : }
437 10 : kbuf = string_term_tdb_data(key);
438 :
439 10 : status = dbwrap_trans_delete(share_db, kbuf);
440 10 : if (!NT_STATUS_IS_OK(status)) {
441 8 : DEBUG(0, ("delete_share_security: Failed to delete entry for "
442 : "share %s: %s\n", c_servicename, nt_errstr(status)));
443 8 : TALLOC_FREE(c_servicename);
444 8 : return status;
445 : }
446 :
447 2 : TALLOC_FREE(c_servicename);
448 2 : return NT_STATUS_OK;
449 : }
450 :
451 : /*******************************************************************
452 : Can this user access with share with the required permissions ?
453 : ********************************************************************/
454 :
455 106316 : bool share_access_check(const struct security_token *token,
456 : const char *sharename,
457 : uint32_t desired_access,
458 : uint32_t *pgranted)
459 : {
460 1657 : uint32_t granted;
461 1657 : NTSTATUS status;
462 106316 : struct security_descriptor *psd = NULL;
463 1657 : size_t sd_size;
464 :
465 106316 : psd = get_share_security(talloc_tos(), sharename, &sd_size);
466 :
467 106316 : if (!psd) {
468 0 : if (pgranted != NULL) {
469 0 : *pgranted = desired_access;
470 : }
471 0 : return false;
472 : }
473 :
474 106316 : status = se_file_access_check(psd, token, true, desired_access, &granted);
475 :
476 106316 : TALLOC_FREE(psd);
477 :
478 106316 : if (pgranted != NULL) {
479 106286 : *pgranted = granted;
480 : }
481 :
482 106316 : return NT_STATUS_IS_OK(status);
483 : }
484 :
485 : /***************************************************************************
486 : Parse the contents of an acl string from a usershare file.
487 : ***************************************************************************/
488 :
489 4 : bool parse_usershare_acl(TALLOC_CTX *ctx, const char *acl_str, struct security_descriptor **ppsd)
490 : {
491 4 : size_t s_size = 0;
492 4 : const char *pacl = acl_str;
493 4 : int num_aces = 0;
494 4 : struct security_ace *ace_list = NULL;
495 4 : struct security_acl *psa = NULL;
496 4 : struct security_descriptor *psd = NULL;
497 4 : size_t sd_size = 0;
498 0 : int i;
499 :
500 4 : *ppsd = NULL;
501 :
502 : /* If the acl string is blank return "Everyone:R" */
503 4 : if (!*acl_str) {
504 0 : struct security_descriptor *default_psd = get_share_security_default(ctx, &s_size, GENERIC_READ_ACCESS);
505 0 : if (!default_psd) {
506 0 : return False;
507 : }
508 0 : *ppsd = default_psd;
509 0 : return True;
510 : }
511 :
512 4 : num_aces = 1;
513 :
514 : /* Add the number of ',' characters to get the number of aces. */
515 4 : num_aces += count_chars(pacl,',');
516 :
517 4 : ace_list = talloc_array(ctx, struct security_ace, num_aces);
518 4 : if (!ace_list) {
519 0 : return False;
520 : }
521 :
522 8 : for (i = 0; i < num_aces; i++) {
523 0 : uint32_t sa;
524 0 : uint32_t g_access;
525 0 : uint32_t s_access;
526 0 : struct dom_sid sid;
527 0 : char *sidstr;
528 4 : enum security_ace_type type = SEC_ACE_TYPE_ACCESS_ALLOWED;
529 :
530 4 : if (!next_token_talloc(ctx, &pacl, &sidstr, ":")) {
531 0 : DEBUG(0,("parse_usershare_acl: malformed usershare acl looking "
532 : "for ':' in string '%s'\n", pacl));
533 0 : return False;
534 : }
535 :
536 4 : if (!string_to_sid(&sid, sidstr)) {
537 0 : DEBUG(0,("parse_usershare_acl: failed to convert %s to sid.\n",
538 : sidstr ));
539 0 : return False;
540 : }
541 :
542 4 : switch (*pacl) {
543 0 : case 'F': /* Full Control, ie. R+W */
544 : case 'f': /* Full Control, ie. R+W */
545 0 : s_access = g_access = GENERIC_ALL_ACCESS;
546 0 : break;
547 4 : case 'R': /* Read only. */
548 : case 'r': /* Read only. */
549 4 : s_access = g_access = GENERIC_READ_ACCESS;
550 4 : break;
551 0 : case 'D': /* Deny all to this SID. */
552 : case 'd': /* Deny all to this SID. */
553 0 : type = SEC_ACE_TYPE_ACCESS_DENIED;
554 0 : s_access = g_access = GENERIC_ALL_ACCESS;
555 0 : break;
556 0 : default:
557 0 : DEBUG(0,("parse_usershare_acl: unknown acl type at %s.\n",
558 : pacl ));
559 0 : return False;
560 : }
561 :
562 4 : pacl++;
563 4 : if (*pacl && *pacl != ',') {
564 0 : DEBUG(0,("parse_usershare_acl: bad acl string at %s.\n",
565 : pacl ));
566 0 : return False;
567 : }
568 4 : pacl++; /* Go past any ',' */
569 :
570 4 : se_map_generic(&s_access, &file_generic_mapping);
571 4 : sa = (g_access | s_access);
572 4 : init_sec_ace(&ace_list[i], &sid, type, sa, 0);
573 : }
574 :
575 4 : if ((psa = make_sec_acl(ctx, NT4_ACL_REVISION, num_aces, ace_list)) != NULL) {
576 4 : psd = make_sec_desc(ctx, SECURITY_DESCRIPTOR_REVISION_1,
577 : SEC_DESC_SELF_RELATIVE, NULL, NULL, NULL,
578 : psa, &sd_size);
579 : }
580 :
581 4 : if (!psd) {
582 0 : DEBUG(0,("parse_usershare_acl: Failed to make SEC_DESC.\n"));
583 0 : return False;
584 : }
585 :
586 4 : *ppsd = psd;
587 4 : return True;
588 : }
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