?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
s3: smbd: VFS: All the places that are currently calling vfs_stat_smb_fname() and...
[Samba.git] / source3 / modules / vfs_acl_common.c
blobc9124a573a86231545738314f5628e5fc66aa0b0
1 /*
2 * Store Windows ACLs in data store - common functions.
3 * #included into modules/vfs_acl_xattr.c and modules/vfs_acl_tdb.c
4 *
5 * Copyright (C) Volker Lendecke, 2008
6 * Copyright (C) Jeremy Allison, 2009
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 3 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "smbd/smbd.h"
23 #include "system/filesys.h"
24 #include "../libcli/security/security.h"
25 #include "../librpc/gen_ndr/ndr_security.h"
26 #include "../lib/util/bitmap.h"
27
28 static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
29 DATA_BLOB *pblob,
30 uint16_t hash_type,
31 uint8_t hash[XATTR_SD_HASH_SIZE]);
32
33 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
34 vfs_handle_struct *handle,
35 files_struct *fsp,
36 const char *name,
37 DATA_BLOB *pblob);
38
39 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
40 files_struct *fsp,
41 DATA_BLOB *pblob);
42
43 #define HASH_SECURITY_INFO (SECINFO_OWNER | \
44 SECINFO_GROUP | \
45 SECINFO_DACL | \
46 SECINFO_SACL)
47
48 /*******************************************************************
49 Hash a security descriptor.
50 *******************************************************************/
51
52 static NTSTATUS hash_blob_sha256(DATA_BLOB blob,
53 uint8_t *hash)
54 {
55 SHA256_CTX tctx;
56
57 memset(hash, '\0', XATTR_SD_HASH_SIZE);
58
59 samba_SHA256_Init(&tctx);
60 samba_SHA256_Update(&tctx, blob.data, blob.length);
61 samba_SHA256_Final(hash, &tctx);
62
63 return NT_STATUS_OK;
64 }
65
66 /*******************************************************************
67 Hash a security descriptor.
68 *******************************************************************/
69
70 static NTSTATUS hash_sd_sha256(struct security_descriptor *psd,
71 uint8_t *hash)
72 {
73 DATA_BLOB blob;
74 NTSTATUS status;
75
76 memset(hash, '\0', XATTR_SD_HASH_SIZE);
77 status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
78 if (!NT_STATUS_IS_OK(status)) {
79 return status;
80 }
81 return hash_blob_sha256(blob, hash);
82 }
83
84 /*******************************************************************
85 Parse out a struct security_descriptor from a DATA_BLOB.
86 *******************************************************************/
87
88 static NTSTATUS parse_acl_blob(const DATA_BLOB *pblob,
89 TALLOC_CTX *mem_ctx,
90 struct security_descriptor **ppdesc,
91 uint16_t *p_hash_type,
92 uint16_t *p_version,
93 uint8_t hash[XATTR_SD_HASH_SIZE],
94 uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE])
95 {
96 struct xattr_NTACL xacl;
97 enum ndr_err_code ndr_err;
98 size_t sd_size;
99 TALLOC_CTX *frame = talloc_stackframe();
100
101 ndr_err = ndr_pull_struct_blob(pblob, frame, &xacl,
102 (ndr_pull_flags_fn_t)ndr_pull_xattr_NTACL);
103
104 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
105 DEBUG(5, ("parse_acl_blob: ndr_pull_xattr_NTACL failed: %s\n",
106 ndr_errstr(ndr_err)));
107 TALLOC_FREE(frame);
108 return ndr_map_error2ntstatus(ndr_err);
109 }
110
111 *p_version = xacl.version;
112
113 switch (xacl.version) {
114 case 1:
115 *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
116 xacl.info.sd->type | SEC_DESC_SELF_RELATIVE,
117 xacl.info.sd->owner_sid,
118 xacl.info.sd->group_sid,
119 xacl.info.sd->sacl,
120 xacl.info.sd->dacl,
121 &sd_size);
122 /* No hash - null out. */
123 *p_hash_type = XATTR_SD_HASH_TYPE_NONE;
124 memset(hash, '\0', XATTR_SD_HASH_SIZE);
125 break;
126 case 2:
127 *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
128 xacl.info.sd_hs2->sd->type | SEC_DESC_SELF_RELATIVE,
129 xacl.info.sd_hs2->sd->owner_sid,
130 xacl.info.sd_hs2->sd->group_sid,
131 xacl.info.sd_hs2->sd->sacl,
132 xacl.info.sd_hs2->sd->dacl,
133 &sd_size);
134 /* No hash - null out. */
135 *p_hash_type = XATTR_SD_HASH_TYPE_NONE;
136 memset(hash, '\0', XATTR_SD_HASH_SIZE);
137 break;
138 case 3:
139 *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
140 xacl.info.sd_hs3->sd->type | SEC_DESC_SELF_RELATIVE,
141 xacl.info.sd_hs3->sd->owner_sid,
142 xacl.info.sd_hs3->sd->group_sid,
143 xacl.info.sd_hs3->sd->sacl,
144 xacl.info.sd_hs3->sd->dacl,
145 &sd_size);
146 *p_hash_type = xacl.info.sd_hs3->hash_type;
147 /* Current version 3 (if no sys acl hash available). */
148 memcpy(hash, xacl.info.sd_hs3->hash, XATTR_SD_HASH_SIZE);
149 break;
150 case 4:
151 *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
152 xacl.info.sd_hs4->sd->type | SEC_DESC_SELF_RELATIVE,
153 xacl.info.sd_hs4->sd->owner_sid,
154 xacl.info.sd_hs4->sd->group_sid,
155 xacl.info.sd_hs4->sd->sacl,
156 xacl.info.sd_hs4->sd->dacl,
157 &sd_size);
158 *p_hash_type = xacl.info.sd_hs4->hash_type;
159 /* Current version 4. */
160 memcpy(hash, xacl.info.sd_hs4->hash, XATTR_SD_HASH_SIZE);
161 memcpy(sys_acl_hash, xacl.info.sd_hs4->sys_acl_hash, XATTR_SD_HASH_SIZE);
162 break;
163 default:
164 TALLOC_FREE(frame);
165 return NT_STATUS_REVISION_MISMATCH;
166 }
167
168 TALLOC_FREE(frame);
169
170 return (*ppdesc != NULL) ? NT_STATUS_OK : NT_STATUS_NO_MEMORY;
171 }
172
173 /*******************************************************************
174 Create a DATA_BLOB from a hash of the security descriptor storead at
175 the system layer and the NT ACL we wish to preserve
176 *******************************************************************/
177
178 static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
179 DATA_BLOB *pblob,
180 uint16_t hash_type,
181 uint8_t hash[XATTR_SD_HASH_SIZE])
182 {
183 struct xattr_NTACL xacl;
184 struct security_descriptor_hash_v3 sd_hs3;
185 enum ndr_err_code ndr_err;
186 TALLOC_CTX *ctx = talloc_tos();
187
188 ZERO_STRUCT(xacl);
189 ZERO_STRUCT(sd_hs3);
190
191 xacl.version = 3;
192 xacl.info.sd_hs3 = &sd_hs3;
193 xacl.info.sd_hs3->sd = discard_const_p(struct security_descriptor, psd);
194 xacl.info.sd_hs3->hash_type = hash_type;
195 memcpy(&xacl.info.sd_hs3->hash[0], hash, XATTR_SD_HASH_SIZE);
196
197 ndr_err = ndr_push_struct_blob(
198 pblob, ctx, &xacl,
199 (ndr_push_flags_fn_t)ndr_push_xattr_NTACL);
200
201 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
202 DEBUG(5, ("create_acl_blob: ndr_push_xattr_NTACL failed: %s\n",
203 ndr_errstr(ndr_err)));
204 return ndr_map_error2ntstatus(ndr_err);
205 }
206
207 return NT_STATUS_OK;
208 }
209
210 /*******************************************************************
211 Create a DATA_BLOB from a hash of the security descriptors
212 (system and NT) stored at the system layer and the NT ACL we wish
213 to preserve.
214 *******************************************************************/
215
216 static NTSTATUS create_sys_acl_blob(const struct security_descriptor *psd,
217 DATA_BLOB *pblob,
218 uint16_t hash_type,
219 uint8_t hash[XATTR_SD_HASH_SIZE],
220 const char *description,
221 uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE])
222 {
223 struct xattr_NTACL xacl;
224 struct security_descriptor_hash_v4 sd_hs4;
225 enum ndr_err_code ndr_err;
226 TALLOC_CTX *ctx = talloc_tos();
227 NTTIME nttime_now;
228 struct timeval now = timeval_current();
229 nttime_now = timeval_to_nttime(&now);
230
231 ZERO_STRUCT(xacl);
232 ZERO_STRUCT(sd_hs4);
233
234 xacl.version = 4;
235 xacl.info.sd_hs4 = &sd_hs4;
236 xacl.info.sd_hs4->sd = discard_const_p(struct security_descriptor, psd);
237 xacl.info.sd_hs4->hash_type = hash_type;
238 memcpy(&xacl.info.sd_hs4->hash[0], hash, XATTR_SD_HASH_SIZE);
239 xacl.info.sd_hs4->description = description;
240 xacl.info.sd_hs4->time = nttime_now;
241 memcpy(&xacl.info.sd_hs4->sys_acl_hash[0], sys_acl_hash, XATTR_SD_HASH_SIZE);
242
243 ndr_err = ndr_push_struct_blob(
244 pblob, ctx, &xacl,
245 (ndr_push_flags_fn_t)ndr_push_xattr_NTACL);
246
247 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
248 DEBUG(5, ("create_acl_blob: ndr_push_xattr_NTACL failed: %s\n",
249 ndr_errstr(ndr_err)));
250 return ndr_map_error2ntstatus(ndr_err);
251 }
252
253 return NT_STATUS_OK;
254 }
255
256 /*******************************************************************
257 Add in 3 inheritable components for a non-inheritable directory ACL.
258 CREATOR_OWNER/CREATOR_GROUP/WORLD.
259 *******************************************************************/
260
261 static NTSTATUS add_directory_inheritable_components(vfs_handle_struct *handle,
262 const char *name,
263 SMB_STRUCT_STAT *psbuf,
264 struct security_descriptor *psd)
265 {
266 struct connection_struct *conn = handle->conn;
267 int num_aces = (psd->dacl ? psd->dacl->num_aces : 0);
268 struct smb_filename smb_fname;
269 enum security_ace_type acltype;
270 uint32_t access_mask;
271 mode_t dir_mode;
272 mode_t file_mode;
273 mode_t mode;
274 struct security_ace *new_ace_list;
275
276 if (psd->dacl) {
277 new_ace_list = talloc_zero_array(psd->dacl,
278 struct security_ace,
279 num_aces + 3);
280 } else {
281 /*
282 * make_sec_acl() at the bottom of this function
283 * dupliates new_ace_list
284 */
285 new_ace_list = talloc_zero_array(talloc_tos(),
286 struct security_ace,
287 num_aces + 3);
288 }
289
290 if (new_ace_list == NULL) {
291 return NT_STATUS_NO_MEMORY;
292 }
293
294 /* Fake a quick smb_filename. */
295 ZERO_STRUCT(smb_fname);
296 smb_fname.st = *psbuf;
297 smb_fname.base_name = discard_const_p(char, name);
298
299 dir_mode = unix_mode(conn,
300 FILE_ATTRIBUTE_DIRECTORY, &smb_fname, NULL);
301 file_mode = unix_mode(conn,
302 FILE_ATTRIBUTE_ARCHIVE, &smb_fname, NULL);
303
304 mode = dir_mode | file_mode;
305
306 DEBUG(10, ("add_directory_inheritable_components: directory %s, "
307 "mode = 0%o\n",
308 name,
309 (unsigned int)mode ));
310
311 if (num_aces) {
312 memcpy(new_ace_list, psd->dacl->aces,
313 num_aces * sizeof(struct security_ace));
314 }
315 access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
316 mode & 0700, false);
317
318 init_sec_ace(&new_ace_list[num_aces],
319 &global_sid_Creator_Owner,
320 acltype,
321 access_mask,
322 SEC_ACE_FLAG_CONTAINER_INHERIT|
323 SEC_ACE_FLAG_OBJECT_INHERIT|
324 SEC_ACE_FLAG_INHERIT_ONLY);
325 access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
326 (mode << 3) & 0700, false);
327 init_sec_ace(&new_ace_list[num_aces+1],
328 &global_sid_Creator_Group,
329 acltype,
330 access_mask,
331 SEC_ACE_FLAG_CONTAINER_INHERIT|
332 SEC_ACE_FLAG_OBJECT_INHERIT|
333 SEC_ACE_FLAG_INHERIT_ONLY);
334 access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
335 (mode << 6) & 0700, false);
336 init_sec_ace(&new_ace_list[num_aces+2],
337 &global_sid_World,
338 acltype,
339 access_mask,
340 SEC_ACE_FLAG_CONTAINER_INHERIT|
341 SEC_ACE_FLAG_OBJECT_INHERIT|
342 SEC_ACE_FLAG_INHERIT_ONLY);
343 if (psd->dacl) {
344 psd->dacl->aces = new_ace_list;
345 psd->dacl->num_aces += 3;
346 } else {
347 psd->dacl = make_sec_acl(psd,
348 NT4_ACL_REVISION,
349 3,
350 new_ace_list);
351 if (psd->dacl == NULL) {
352 return NT_STATUS_NO_MEMORY;
353 }
354 }
355 return NT_STATUS_OK;
356 }
357
358 /*******************************************************************
359 Pull a DATA_BLOB from an xattr given a pathname.
360 If the hash doesn't match, or doesn't exist - return the underlying
361 filesystem sd.
362 *******************************************************************/
363
364 static NTSTATUS get_nt_acl_internal(vfs_handle_struct *handle,
365 files_struct *fsp,
366 const char *name,
367 uint32_t security_info,
368 TALLOC_CTX *mem_ctx,
369 struct security_descriptor **ppdesc)
370 {
371 DATA_BLOB blob = data_blob_null;
372 NTSTATUS status;
373 uint16_t hash_type = XATTR_SD_HASH_TYPE_NONE;
374 uint16_t xattr_version = 0;
375 uint8_t hash[XATTR_SD_HASH_SIZE];
376 uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
377 uint8_t hash_tmp[XATTR_SD_HASH_SIZE];
378 uint8_t sys_acl_hash_tmp[XATTR_SD_HASH_SIZE];
379 struct security_descriptor *psd = NULL;
380 struct security_descriptor *pdesc_next = NULL;
381 bool ignore_file_system_acl = lp_parm_bool(SNUM(handle->conn),
382 ACL_MODULE_NAME,
383 "ignore system acls",
384 false);
385 TALLOC_CTX *frame = talloc_stackframe();
386
387 if (fsp && name == NULL) {
388 name = fsp->fsp_name->base_name;
389 }
390
391 DEBUG(10, ("get_nt_acl_internal: name=%s\n", name));
392
393 status = get_acl_blob(frame, handle, fsp, name, &blob);
394 if (!NT_STATUS_IS_OK(status)) {
395 DEBUG(10, ("get_nt_acl_internal: get_acl_blob returned %s\n",
396 nt_errstr(status)));
397 psd = NULL;
398 goto out;
399 } else {
400 status = parse_acl_blob(&blob, mem_ctx, &psd,
401 &hash_type, &xattr_version, &hash[0], &sys_acl_hash[0]);
402 if (!NT_STATUS_IS_OK(status)) {
403 DEBUG(10, ("parse_acl_blob returned %s\n",
404 nt_errstr(status)));
405 psd = NULL;
406 goto out;
407 }
408 }
409
410 /* Ensure we don't leak psd if we don't choose it.
411 *
412 * We don't allocate it onto frame as it is preferred not to
413 * steal from a talloc pool.
414 */
415 talloc_steal(frame, psd);
416
417 /* determine which type of xattr we got */
418 switch (xattr_version) {
419 case 1:
420 case 2:
421 /* These xattr types are unilatteral, they do not
422 * require confirmation of the hash. In particular,
423 * the NTVFS file server uses version 1, but
424 * 'samba-tool ntacl' can set these as well */
425 goto out;
426 case 3:
427 case 4:
428 if (ignore_file_system_acl) {
429 goto out;
430 }
431
432 break;
433 default:
434 DEBUG(10, ("get_nt_acl_internal: ACL blob revision "
435 "mismatch (%u) for file %s\n",
436 (unsigned int)hash_type,
437 name));
438 TALLOC_FREE(psd);
439 psd = NULL;
440 goto out;
441 }
442
443 /* determine which type of xattr we got */
444 if (hash_type != XATTR_SD_HASH_TYPE_SHA256) {
445 DEBUG(10, ("get_nt_acl_internal: ACL blob hash type "
446 "(%u) unexpected for file %s\n",
447 (unsigned int)hash_type,
448 name));
449 TALLOC_FREE(psd);
450 psd = NULL;
451 goto out;
452 }
453
454 /* determine which type of xattr we got */
455 switch (xattr_version) {
456 case 4:
457 {
458 int ret;
459 char *sys_acl_blob_description;
460 DATA_BLOB sys_acl_blob;
461 if (fsp) {
462 /* Get the full underlying sd, then hash. */
463 ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
464 fsp,
465 frame,
466 &sys_acl_blob_description,
467 &sys_acl_blob);
468 } else {
469 /* Get the full underlying sd, then hash. */
470 ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FILE(handle,
471 name,
472 frame,
473 &sys_acl_blob_description,
474 &sys_acl_blob);
475 }
476
477 /* If we fail to get the ACL blob (for some reason) then this
478 * is not fatal, we just work based on the NT ACL only */
479 if (ret == 0) {
480 status = hash_blob_sha256(sys_acl_blob, sys_acl_hash_tmp);
481 if (!NT_STATUS_IS_OK(status)) {
482 TALLOC_FREE(frame);
483 return status;
484 }
485
486 if (memcmp(&sys_acl_hash[0], &sys_acl_hash_tmp[0],
487 XATTR_SD_HASH_SIZE) == 0) {
488 /* Hash matches, return blob sd. */
489 DEBUG(10, ("get_nt_acl_internal: blob hash "
490 "matches for file %s\n",
491 name ));
492 goto out;
493 }
494 }
495
496 /* Otherwise, fall though and see if the NT ACL hash matches */
497 }
498 case 3:
499 /* Get the full underlying sd for the hash
500 or to return as backup. */
501 if (fsp) {
502 status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
503 fsp,
504 HASH_SECURITY_INFO,
505 mem_ctx,
506 &pdesc_next);
507 } else {
508 status = SMB_VFS_NEXT_GET_NT_ACL(handle,
509 name,
510 HASH_SECURITY_INFO,
511 mem_ctx,
512 &pdesc_next);
513 }
514
515 if (!NT_STATUS_IS_OK(status)) {
516 DEBUG(10, ("get_nt_acl_internal: get_next_acl for file %s "
517 "returned %s\n",
518 name,
519 nt_errstr(status)));
520 TALLOC_FREE(frame);
521 return status;
522 }
523
524 /* Ensure we don't leak psd_next if we don't choose it.
525 *
526 * We don't allocate it onto frame as it is preferred not to
527 * steal from a talloc pool.
528 */
529 talloc_steal(frame, pdesc_next);
530
531 status = hash_sd_sha256(pdesc_next, hash_tmp);
532 if (!NT_STATUS_IS_OK(status)) {
533 TALLOC_FREE(psd);
534 psd = pdesc_next;
535 goto out;
536 }
537
538 if (memcmp(&hash[0], &hash_tmp[0], XATTR_SD_HASH_SIZE) == 0) {
539 /* Hash matches, return blob sd. */
540 DEBUG(10, ("get_nt_acl_internal: blob hash "
541 "matches for file %s\n",
542 name ));
543 goto out;
544 }
545
546 /* Hash doesn't match, return underlying sd. */
547 DEBUG(10, ("get_nt_acl_internal: blob hash "
548 "does not match for file %s - returning "
549 "file system SD mapping.\n",
550 name ));
551
552 if (DEBUGLEVEL >= 10) {
553 DEBUG(10,("get_nt_acl_internal: acl for blob hash for %s is:\n",
554 name ));
555 NDR_PRINT_DEBUG(security_descriptor, pdesc_next);
556 }
557
558 TALLOC_FREE(psd);
559 psd = pdesc_next;
560 }
561 out:
562
563 if (psd == NULL) {
564 /* Get the full underlying sd, as we failed to get the
565 * blob for the hash, or the revision/hash type wasn't
566 * known */
567 if (fsp) {
568 status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
569 fsp,
570 security_info,
571 mem_ctx,
572 &pdesc_next);
573 } else {
574 status = SMB_VFS_NEXT_GET_NT_ACL(handle,
575 name,
576 security_info,
577 mem_ctx,
578 &pdesc_next);
579 }
580
581 if (!NT_STATUS_IS_OK(status)) {
582 DEBUG(10, ("get_nt_acl_internal: get_next_acl for file %s "
583 "returned %s\n",
584 name,
585 nt_errstr(status)));
586 TALLOC_FREE(frame);
587 return status;
588 }
589
590 /* Ensure we don't leak psd_next if we don't choose it.
591 *
592 * We don't allocate it onto frame as it is preferred not to
593 * steal from a talloc pool.
594 */
595 talloc_steal(frame, pdesc_next);
596 psd = pdesc_next;
597 }
598
599 if (psd != pdesc_next) {
600 /* We're returning the blob, throw
601 * away the filesystem SD. */
602 TALLOC_FREE(pdesc_next);
603 } else {
604 SMB_STRUCT_STAT sbuf;
605 SMB_STRUCT_STAT *psbuf = &sbuf;
606 bool is_directory = false;
607 /*
608 * We're returning the underlying ACL from the
609 * filesystem. If it's a directory, and has no
610 * inheritable ACE entries we have to fake them.
611 */
612 if (fsp) {
613 status = vfs_stat_fsp(fsp);
614 if (!NT_STATUS_IS_OK(status)) {
615 TALLOC_FREE(frame);
616 return status;
617 }
618 psbuf = &fsp->fsp_name->st;
619 } else {
620 /*
621 * https://bugzilla.samba.org/show_bug.cgi?id=11249
622 *
623 * We are currently guaranteed that 'name' here is
624 * a smb_fname->base_name, which *cannot* contain
625 * a stream name (':'). vfs_stat_smb_fname() splits
626 * a name into a base name + stream name, which
627 * when we get here we know we've already done.
628 * So we have to call the stat or lstat VFS
629 * calls directly here. Else, a base_name that
630 * contains a ':' (from a demangled name) will
631 * get split again.
632 *
633 * FIXME.
634 * This uglyness will go away once smb_fname
635 * is fully plumbed through the VFS.
636 */
637 int ret = vfs_stat_smb_basename(handle->conn,
638 name,
639 &sbuf);
640 if (ret == -1) {
641 TALLOC_FREE(frame);
642 return map_nt_error_from_unix(errno);
643 }
644 }
645 is_directory = S_ISDIR(psbuf->st_ex_mode);
646
647 if (ignore_file_system_acl) {
648 TALLOC_FREE(pdesc_next);
649 status = make_default_filesystem_acl(mem_ctx,
650 name,
651 psbuf,
652 &psd);
653 if (!NT_STATUS_IS_OK(status)) {
654 TALLOC_FREE(frame);
655 return status;
656 }
657 } else {
658 if (is_directory &&
659 !sd_has_inheritable_components(psd,
660 true)) {
661 status = add_directory_inheritable_components(
662 handle,
663 name,
664 psbuf,
665 psd);
666 if (!NT_STATUS_IS_OK(status)) {
667 TALLOC_FREE(frame);
668 return status;
669 }
670 }
671 /* The underlying POSIX module always sets
672 the ~SEC_DESC_DACL_PROTECTED bit, as ACLs
673 can't be inherited in this way under POSIX.
674 Remove it for Windows-style ACLs. */
675 psd->type &= ~SEC_DESC_DACL_PROTECTED;
676 }
677 }
678
679 if (!(security_info & SECINFO_OWNER)) {
680 psd->owner_sid = NULL;
681 }
682 if (!(security_info & SECINFO_GROUP)) {
683 psd->group_sid = NULL;
684 }
685 if (!(security_info & SECINFO_DACL)) {
686 psd->type &= ~SEC_DESC_DACL_PRESENT;
687 psd->dacl = NULL;
688 }
689 if (!(security_info & SECINFO_SACL)) {
690 psd->type &= ~SEC_DESC_SACL_PRESENT;
691 psd->sacl = NULL;
692 }
693
694 TALLOC_FREE(blob.data);
695
696 if (DEBUGLEVEL >= 10) {
697 DEBUG(10,("get_nt_acl_internal: returning acl for %s is:\n",
698 name ));
699 NDR_PRINT_DEBUG(security_descriptor, psd);
700 }
701
702 /* The VFS API is that the ACL is expected to be on mem_ctx */
703 *ppdesc = talloc_move(mem_ctx, &psd);
704
705 TALLOC_FREE(frame);
706 return NT_STATUS_OK;
707 }
708
709 /*********************************************************************
710 Fetch a security descriptor given an fsp.
711 *********************************************************************/
712
713 static NTSTATUS fget_nt_acl_common(vfs_handle_struct *handle,
714 files_struct *fsp,
715 uint32_t security_info,
716 TALLOC_CTX *mem_ctx,
717 struct security_descriptor **ppdesc)
718 {
719 return get_nt_acl_internal(handle, fsp,
720 NULL, security_info, mem_ctx, ppdesc);
721 }
722
723 /*********************************************************************
724 Fetch a security descriptor given a pathname.
725 *********************************************************************/
726
727 static NTSTATUS get_nt_acl_common(vfs_handle_struct *handle,
728 const char *name,
729 uint32_t security_info,
730 TALLOC_CTX *mem_ctx,
731 struct security_descriptor **ppdesc)
732 {
733 return get_nt_acl_internal(handle, NULL,
734 name, security_info, mem_ctx, ppdesc);
735 }
736
737 /*********************************************************************
738 Store a security descriptor given an fsp.
739 *********************************************************************/
740
741 static NTSTATUS fset_nt_acl_common(vfs_handle_struct *handle, files_struct *fsp,
742 uint32_t security_info_sent, const struct security_descriptor *orig_psd)
743 {
744 NTSTATUS status;
745 int ret;
746 DATA_BLOB blob, sys_acl_blob;
747 struct security_descriptor *pdesc_next = NULL;
748 struct security_descriptor *psd = NULL;
749 uint8_t hash[XATTR_SD_HASH_SIZE];
750 uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
751 bool chown_needed = false;
752 char *sys_acl_description;
753 TALLOC_CTX *frame = talloc_stackframe();
754
755 if (DEBUGLEVEL >= 10) {
756 DEBUG(10,("fset_nt_acl_xattr: incoming sd for file %s\n",
757 fsp_str_dbg(fsp)));
758 NDR_PRINT_DEBUG(security_descriptor,
759 discard_const_p(struct security_descriptor, orig_psd));
760 }
761
762 status = get_nt_acl_internal(handle, fsp,
763 NULL,
764 SECINFO_OWNER|SECINFO_GROUP|SECINFO_DACL|SECINFO_SACL,
765 frame,
766 &psd);
767
768 if (!NT_STATUS_IS_OK(status)) {
769 TALLOC_FREE(frame);
770 return status;
771 }
772
773 psd->revision = orig_psd->revision;
774 /* All our SD's are self relative. */
775 psd->type = orig_psd->type | SEC_DESC_SELF_RELATIVE;
776
777 if ((security_info_sent & SECINFO_OWNER) && (orig_psd->owner_sid != NULL)) {
778 if (!dom_sid_equal(orig_psd->owner_sid, psd->owner_sid)) {
779 /* We're changing the owner. */
780 chown_needed = true;
781 }
782 psd->owner_sid = orig_psd->owner_sid;
783 }
784 if ((security_info_sent & SECINFO_GROUP) && (orig_psd->group_sid != NULL)) {
785 if (!dom_sid_equal(orig_psd->group_sid, psd->group_sid)) {
786 /* We're changing the group. */
787 chown_needed = true;
788 }
789 psd->group_sid = orig_psd->group_sid;
790 }
791 if (security_info_sent & SECINFO_DACL) {
792 psd->dacl = orig_psd->dacl;
793 psd->type |= SEC_DESC_DACL_PRESENT;
794 }
795 if (security_info_sent & SECINFO_SACL) {
796 psd->sacl = orig_psd->sacl;
797 psd->type |= SEC_DESC_SACL_PRESENT;
798 }
799
800 status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
801 if (!NT_STATUS_IS_OK(status)) {
802 if (!NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
803 TALLOC_FREE(frame);
804 return status;
805 }
806 /* We got access denied here. If we're already root,
807 or we didn't need to do a chown, or the fsp isn't
808 open with WRITE_OWNER access, just return. */
809 if (get_current_uid(handle->conn) == 0 ||
810 chown_needed == false ||
811 !(fsp->access_mask & SEC_STD_WRITE_OWNER)) {
812 TALLOC_FREE(frame);
813 return NT_STATUS_ACCESS_DENIED;
814 }
815
816 DEBUG(10,("fset_nt_acl_common: overriding chown on file %s "
817 "for sid %s\n",
818 fsp_str_dbg(fsp),
819 sid_string_tos(psd->owner_sid)
820 ));
821
822 /* Ok, we failed to chown and we have
823 SEC_STD_WRITE_OWNER access - override. */
824 become_root();
825 status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp,
826 security_info_sent, psd);
827 unbecome_root();
828 if (!NT_STATUS_IS_OK(status)) {
829 TALLOC_FREE(frame);
830 return status;
831 }
832 }
833
834 /* Get the full underlying sd, then hash. */
835 status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
836 fsp,
837 HASH_SECURITY_INFO,
838 frame,
839 &pdesc_next);
840
841 if (!NT_STATUS_IS_OK(status)) {
842 TALLOC_FREE(frame);
843 return status;
844 }
845
846 status = hash_sd_sha256(pdesc_next, hash);
847 if (!NT_STATUS_IS_OK(status)) {
848 TALLOC_FREE(frame);
849 return status;
850 }
851
852 /* Get the full underlying sd, then hash. */
853 ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
854 fsp,
855 frame,
856 &sys_acl_description,
857 &sys_acl_blob);
858
859 /* If we fail to get the ACL blob (for some reason) then this
860 * is not fatal, we just work based on the NT ACL only */
861 if (ret != 0) {
862 if (DEBUGLEVEL >= 10) {
863 DEBUG(10,("fset_nt_acl_xattr: storing xattr sd for file %s\n",
864 fsp_str_dbg(fsp)));
865 NDR_PRINT_DEBUG(security_descriptor,
866 discard_const_p(struct security_descriptor, psd));
867
868 DEBUG(10,("fset_nt_acl_xattr: storing has in xattr sd based on \n"));
869 NDR_PRINT_DEBUG(security_descriptor,
870 discard_const_p(struct security_descriptor, pdesc_next));
871 }
872 status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
873 if (!NT_STATUS_IS_OK(status)) {
874 DEBUG(10, ("fset_nt_acl_xattr: create_acl_blob failed\n"));
875 TALLOC_FREE(frame);
876 return status;
877 }
878
879 status = store_acl_blob_fsp(handle, fsp, &blob);
880
881 TALLOC_FREE(frame);
882 return status;
883 }
884
885 status = hash_blob_sha256(sys_acl_blob, sys_acl_hash);
886 if (!NT_STATUS_IS_OK(status)) {
887 TALLOC_FREE(frame);
888 return status;
889 }
890
891 if (DEBUGLEVEL >= 10) {
892 DEBUG(10,("fset_nt_acl_xattr: storing xattr sd for file %s based on system ACL\n",
893 fsp_str_dbg(fsp)));
894 NDR_PRINT_DEBUG(security_descriptor,
895 discard_const_p(struct security_descriptor, psd));
896
897 DEBUG(10,("fset_nt_acl_xattr: storing hash in xattr sd based on system ACL and:\n"));
898 NDR_PRINT_DEBUG(security_descriptor,
899 discard_const_p(struct security_descriptor, pdesc_next));
900 }
901
902 /* We store hashes of both the sys ACL blob and the NT
903 * security desciptor mapped from that ACL so as to improve
904 * our chances against some inadvertant change breaking the
905 * hash used */
906 status = create_sys_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash,
907 sys_acl_description, sys_acl_hash);
908 if (!NT_STATUS_IS_OK(status)) {
909 DEBUG(10, ("fset_nt_acl_xattr: create_sys_acl_blob failed\n"));
910 TALLOC_FREE(frame);
911 return status;
912 }
913
914 status = store_acl_blob_fsp(handle, fsp, &blob);
915
916 TALLOC_FREE(frame);
917 return status;
918 }
919
920 static int acl_common_remove_object(vfs_handle_struct *handle,
921 const char *path,
922 bool is_directory)
923 {
924 connection_struct *conn = handle->conn;
925 struct file_id id;
926 files_struct *fsp = NULL;
927 int ret = 0;
928 char *parent_dir = NULL;
929 const char *final_component = NULL;
930 struct smb_filename local_fname;
931 int saved_errno = 0;
932 char *saved_dir = NULL;
933
934 saved_dir = vfs_GetWd(talloc_tos(),conn);
935 if (!saved_dir) {
936 saved_errno = errno;
937 goto out;
938 }
939
940 if (!parent_dirname(talloc_tos(), path,
941 &parent_dir, &final_component)) {
942 saved_errno = ENOMEM;
943 goto out;
944 }
945
946 DEBUG(10,("acl_common_remove_object: removing %s %s/%s\n",
947 is_directory ? "directory" : "file",
948 parent_dir, final_component ));
949
950 /* cd into the parent dir to pin it. */
951 ret = vfs_ChDir(conn, parent_dir);
952 if (ret == -1) {
953 saved_errno = errno;
954 goto out;
955 }
956
957 ZERO_STRUCT(local_fname);
958 local_fname.base_name = discard_const_p(char, final_component);
959
960 /* Must use lstat here. */
961 ret = SMB_VFS_LSTAT(conn, &local_fname);
962 if (ret == -1) {
963 saved_errno = errno;
964 goto out;
965 }
966
967 /* Ensure we have this file open with DELETE access. */
968 id = vfs_file_id_from_sbuf(conn, &local_fname.st);
969 for (fsp = file_find_di_first(conn->sconn, id); fsp;
970 fsp = file_find_di_next(fsp)) {
971 if (fsp->access_mask & DELETE_ACCESS &&
972 fsp->delete_on_close) {
973 /* We did open this for delete,
974 * allow the delete as root.
975 */
976 break;
977 }
978 }
979
980 if (!fsp) {
981 DEBUG(10,("acl_common_remove_object: %s %s/%s "
982 "not an open file\n",
983 is_directory ? "directory" : "file",
984 parent_dir, final_component ));
985 saved_errno = EACCES;
986 goto out;
987 }
988
989 become_root();
990 if (is_directory) {
991 ret = SMB_VFS_NEXT_RMDIR(handle, final_component);
992 } else {
993 ret = SMB_VFS_NEXT_UNLINK(handle, &local_fname);
994 }
995 unbecome_root();
996
997 if (ret == -1) {
998 saved_errno = errno;
999 }
1000
1001 out:
1002
1003 TALLOC_FREE(parent_dir);
1004
1005 if (saved_dir) {
1006 vfs_ChDir(conn, saved_dir);
1007 }
1008 if (saved_errno) {
1009 errno = saved_errno;
1010 }
1011 return ret;
1012 }
1013
1014 static int rmdir_acl_common(struct vfs_handle_struct *handle,
1015 const char *path)
1016 {
1017 int ret;
1018
1019 /* Try the normal rmdir first. */
1020 ret = SMB_VFS_NEXT_RMDIR(handle, path);
1021 if (ret == 0) {
1022 return 0;
1023 }
1024 if (errno == EACCES || errno == EPERM) {
1025 /* Failed due to access denied,
1026 see if we need to root override. */
1027 return acl_common_remove_object(handle,
1028 path,
1029 true);
1030 }
1031
1032 DEBUG(10,("rmdir_acl_common: unlink of %s failed %s\n",
1033 path,
1034 strerror(errno) ));
1035 return -1;
1036 }
1037
1038 static int unlink_acl_common(struct vfs_handle_struct *handle,
1039 const struct smb_filename *smb_fname)
1040 {
1041 int ret;
1042
1043 /* Try the normal unlink first. */
1044 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname);
1045 if (ret == 0) {
1046 return 0;
1047 }
1048 if (errno == EACCES || errno == EPERM) {
1049 /* Failed due to access denied,
1050 see if we need to root override. */
1051
1052 /* Don't do anything fancy for streams. */
1053 if (smb_fname->stream_name) {
1054 return -1;
1055 }
1056 return acl_common_remove_object(handle,
1057 smb_fname->base_name,
1058 false);
1059 }
1060
1061 DEBUG(10,("unlink_acl_common: unlink of %s failed %s\n",
1062 smb_fname->base_name,
1063 strerror(errno) ));
1064 return -1;
1065 }
1066
1067 static int chmod_acl_module_common(struct vfs_handle_struct *handle,
1068 const char *path, mode_t mode)
1069 {
1070 if (lp_posix_pathnames()) {
1071 /* Only allow this on POSIX pathnames. */
1072 return SMB_VFS_NEXT_CHMOD(handle, path, mode);
1073 }
1074 return 0;
1075 }
1076
1077 static int fchmod_acl_module_common(struct vfs_handle_struct *handle,
1078 struct files_struct *fsp, mode_t mode)
1079 {
1080 if (fsp->posix_open) {
1081 /* Only allow this on POSIX opens. */
1082 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
1083 }
1084 return 0;
1085 }
1086
1087 static int chmod_acl_acl_module_common(struct vfs_handle_struct *handle,
1088 const char *name, mode_t mode)
1089 {
1090 if (lp_posix_pathnames()) {
1091 /* Only allow this on POSIX pathnames. */
1092 return SMB_VFS_NEXT_CHMOD_ACL(handle, name, mode);
1093 }
1094 return 0;
1095 }
1096
1097 static int fchmod_acl_acl_module_common(struct vfs_handle_struct *handle,
1098 struct files_struct *fsp, mode_t mode)
1099 {
1100 if (fsp->posix_open) {
1101 /* Only allow this on POSIX opens. */
1102 return SMB_VFS_NEXT_FCHMOD_ACL(handle, fsp, mode);
1103 }
1104 return 0;
1105 }
Samba GIT mirror