xref: /illumos-gate/usr/src/uts/common/fs/smbsrv/smb_delete.c (revision c5bab7026b8e0ac44b25ee08507ea360f177d844)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
25  */
26 
27 #include <sys/sunddi.h>
28 #include <sys/nbmlock.h>
29 
30 #include <smbsrv/smb_kproto.h>
31 #include <smbsrv/smb_fsops.h>
32 #include <smbsrv/smbinfo.h>
33 
34 static int smb_delete_check_path(smb_request_t *);
35 static int smb_delete_single_file(smb_request_t *, smb_error_t *);
36 static int smb_delete_multiple_files(smb_request_t *, smb_error_t *);
37 static int smb_delete_find_fname(smb_request_t *, smb_odir_t *, char *, int);
38 static int smb_delete_check_dosattr(smb_request_t *, smb_error_t *);
39 static int smb_delete_remove_file(smb_request_t *, smb_error_t *);
40 
41 static void smb_delete_error(smb_error_t *, uint32_t, uint16_t, uint16_t);
42 
43 /*
44  * smb_com_delete
45  *
46  * The delete file message is sent to delete a data file. The appropriate
47  * Tid and additional pathname are passed. Read only files may not be
48  * deleted, the read-only attribute must be reset prior to file deletion.
49  *
50  * NT supports a hidden permission known as File Delete Child (FDC). If
51  * the user has FullControl access to a directory, the user is permitted
52  * to delete any object in the directory regardless of the permissions
53  * on the object.
54  *
55  * Client Request                     Description
56  * ================================== =================================
57  * UCHAR WordCount;                   Count of parameter words = 1
58  * USHORT SearchAttributes;
59  * USHORT ByteCount;                  Count of data bytes; min = 2
60  * UCHAR BufferFormat;                0x04
61  * STRING FileName[];                 File name
62  *
63  * Multiple files may be deleted in response to a single request as
64  * SMB_COM_DELETE supports wildcards
65  *
66  * SearchAttributes indicates the attributes that the target file(s) must
67  * have. If the attribute is zero then only normal files are deleted. If
68  * the system file or hidden attributes are specified then the delete is
69  * inclusive -both the specified type(s) of files and normal files are
70  * deleted. Attributes are described in the "Attribute Encoding" section
71  * of this document.
72  *
73  * If bit0 of the Flags2 field of the SMB header is set, a pattern is
74  * passed in, and the file has a long name, then the passed pattern  much
75  * match the long file name for the delete to succeed. If bit0 is clear, a
76  * pattern is passed in, and the file has a long name, then the passed
77  * pattern must match the file's short name for the deletion to succeed.
78  *
79  * Server Response                    Description
80  * ================================== =================================
81  * UCHAR WordCount;                   Count of parameter words = 0
82  * USHORT ByteCount;                  Count of data bytes = 0
83  *
84  * 4.2.10.1  Errors
85  *
86  * ERRDOS/ERRbadpath
87  * ERRDOS/ERRbadfile
88  * ERRDOS/ERRnoaccess
89  * ERRDOS/ERRbadshare	# returned by NT for files that are already open
90  * ERRHRD/ERRnowrite
91  * ERRSRV/ERRaccess
92  * ERRSRV/ERRinvdevice
93  * ERRSRV/ERRinvid
94  * ERRSRV/ERRbaduid
95  */
96 smb_sdrc_t
97 smb_pre_delete(smb_request_t *sr)
98 {
99 	int rc;
100 	smb_fqi_t *fqi;
101 
102 	fqi = &sr->arg.dirop.fqi;
103 
104 	if ((rc = smbsr_decode_vwv(sr, "w", &fqi->fq_sattr)) == 0)
105 		rc = smbsr_decode_data(sr, "%S", sr, &fqi->fq_path.pn_path);
106 
107 	DTRACE_SMB_2(op__Delete__start, smb_request_t *, sr, smb_fqi_t *, fqi);
108 
109 	return ((rc == 0) ? SDRC_SUCCESS : SDRC_ERROR);
110 }
111 
112 void
113 smb_post_delete(smb_request_t *sr)
114 {
115 	DTRACE_SMB_1(op__Delete__done, smb_request_t *, sr);
116 }
117 
118 /*
119  * smb_com_delete
120  *
121  * 1. intialize, pre-process and validate pathname
122  *
123  * 2. process the path to get directory node & last_comp,
124  *    store these in fqi
125  *    - If smb_pathname_reduce cannot find the specified path,
126  *      the error (ENOTDIR) is translated to NT_STATUS_OBJECT_PATH_NOT_FOUND
127  *      if the target is a single file (no wildcards).  If there are
128  *      wildcards in the last_comp, NT_STATUS_OBJECT_NAME_NOT_FOUND is
129  *      used instead.
130  *    - If the directory node is the mount point and the last component
131  *      is ".." NT_STATUS_OBJECT_PATH_SYNTAX_BAD is returned.
132  *
133  * 3. check access permissions
134  *
135  * 4. invoke the appropriate deletion routine to find and remove
136  *    the specified file(s).
137  *    - if target is a single file (no wildcards) - smb_delete_single_file
138  *    - if the target contains wildcards - smb_delete_multiple_files
139  *
140  * Returns: SDRC_SUCCESS or SDRC_ERROR
141  */
142 smb_sdrc_t
143 smb_com_delete(smb_request_t *sr)
144 {
145 	int rc;
146 	smb_error_t err;
147 	uint32_t status;
148 	boolean_t wildcards = B_FALSE;
149 	smb_fqi_t *fqi;
150 	smb_pathname_t *pn;
151 
152 	fqi = &sr->arg.dirop.fqi;
153 	pn = &fqi->fq_path;
154 
155 	smb_pathname_init(sr, pn, pn->pn_path);
156 	if (!smb_pathname_validate(sr, pn))
157 		return (SDRC_ERROR);
158 	if (smb_delete_check_path(sr) != 0)
159 		return (SDRC_ERROR);
160 
161 	wildcards = smb_contains_wildcards(pn->pn_fname);
162 
163 	rc = smb_pathname_reduce(sr, sr->user_cr, fqi->fq_path.pn_path,
164 	    sr->tid_tree->t_snode, sr->tid_tree->t_snode,
165 	    &fqi->fq_dnode, fqi->fq_last_comp);
166 	if (rc == 0) {
167 		if (!smb_node_is_dir(fqi->fq_dnode)) {
168 			smb_node_release(fqi->fq_dnode);
169 			rc = ENOTDIR;
170 		}
171 	}
172 	if (rc != 0) {
173 		if (rc == ENOTDIR) {
174 			if (wildcards)
175 				status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
176 			else
177 				status = NT_STATUS_OBJECT_PATH_NOT_FOUND;
178 			smbsr_error(sr, status, ERRDOS, ERROR_FILE_NOT_FOUND);
179 		} else {
180 			smbsr_errno(sr, rc);
181 		}
182 
183 		return (SDRC_ERROR);
184 	}
185 
186 	if ((fqi->fq_dnode == sr->tid_tree->t_snode) &&
187 	    (strcmp(fqi->fq_last_comp, "..") == 0)) {
188 		smb_node_release(fqi->fq_dnode);
189 		smbsr_error(sr, NT_STATUS_OBJECT_PATH_SYNTAX_BAD,
190 		    ERRDOS, ERROR_BAD_PATHNAME);
191 		return (SDRC_ERROR);
192 	}
193 
194 	rc = smb_fsop_access(sr, sr->user_cr, fqi->fq_dnode,
195 	    FILE_LIST_DIRECTORY);
196 	if (rc != 0) {
197 		smb_node_release(fqi->fq_dnode);
198 		smbsr_error(sr, NT_STATUS_ACCESS_DENIED,
199 		    ERRDOS, ERROR_ACCESS_DENIED);
200 		return (SDRC_ERROR);
201 	}
202 
203 	if (wildcards)
204 		rc = smb_delete_multiple_files(sr, &err);
205 	else
206 		rc = smb_delete_single_file(sr, &err);
207 
208 	smb_node_release(fqi->fq_dnode);
209 
210 	if (rc != 0)
211 		smbsr_set_error(sr, &err);
212 	else
213 		rc = smbsr_encode_empty_result(sr);
214 
215 	return (rc == 0 ? SDRC_SUCCESS : SDRC_ERROR);
216 }
217 
218 /*
219  * smb_delete_single_file
220  *
221  * Find the specified file and, if its attributes match the search
222  * criteria, delete it.
223  *
224  * Returns 0 - success (file deleted)
225  *        -1 - error, err is populated with error details
226  */
227 static int
228 smb_delete_single_file(smb_request_t *sr, smb_error_t *err)
229 {
230 	smb_fqi_t *fqi;
231 	smb_pathname_t *pn;
232 
233 	fqi = &sr->arg.dirop.fqi;
234 	pn = &fqi->fq_path;
235 
236 	/* pn already initialized and validated */
237 	if (!smb_validate_object_name(sr, pn)) {
238 		smb_delete_error(err, sr->smb_error.status,
239 		    ERRDOS, ERROR_INVALID_NAME);
240 		return (-1);
241 	}
242 
243 	if (smb_fsop_lookup_name(sr, sr->user_cr, 0, sr->tid_tree->t_snode,
244 	    fqi->fq_dnode, fqi->fq_last_comp, &fqi->fq_fnode) != 0) {
245 		smb_delete_error(err, NT_STATUS_OBJECT_NAME_NOT_FOUND,
246 		    ERRDOS, ERROR_FILE_NOT_FOUND);
247 		return (-1);
248 	}
249 
250 	if (smb_delete_check_dosattr(sr, err) != 0) {
251 		smb_node_release(fqi->fq_fnode);
252 		return (-1);
253 	}
254 
255 	if (smb_delete_remove_file(sr, err) != 0) {
256 		smb_node_release(fqi->fq_fnode);
257 		return (-1);
258 	}
259 
260 	smb_node_release(fqi->fq_fnode);
261 	return (0);
262 }
263 
264 /*
265  * smb_delete_multiple_files
266  *
267  * For each matching file found by smb_delete_find_fname:
268  * 1. lookup file
269  * 2. check the file's attributes
270  *    - The search ends with an error if a readonly file
271  *      (NT_STATUS_CANNOT_DELETE) is matched.
272  *    - The search ends (but not an error) if a directory is
273  *      matched and the request's search did not include
274  *      directories.
275  *    - Otherwise, if smb_delete_check_dosattr fails the file
276  *      is skipped and the search continues (at step 1)
277  * 3. delete the file
278  *
279  * Returns 0 - success
280  *        -1 - error, err is populated with error details
281  */
282 static int
283 smb_delete_multiple_files(smb_request_t *sr, smb_error_t *err)
284 {
285 	char namebuf[MAXNAMELEN];
286 	smb_fqi_t *fqi;
287 	smb_odir_t *od;
288 	uint32_t status;
289 	int rc, deleted = 0;
290 
291 	fqi = &sr->arg.dirop.fqi;
292 
293 	/*
294 	 * Specify all search attributes (SMB_SEARCH_ATTRIBUTES) so that
295 	 * delete-specific checking can be done (smb_delete_check_dosattr).
296 	 */
297 	status = smb_odir_openpath(sr, fqi->fq_path.pn_path,
298 	    SMB_SEARCH_ATTRIBUTES, 0, &od);
299 	if (status != 0) {
300 		err->status = status;
301 		return (-1);
302 	}
303 
304 	for (;;) {
305 		rc = smb_delete_find_fname(sr, od, namebuf, MAXNAMELEN);
306 		if (rc != 0)
307 			break;
308 
309 		rc = smb_fsop_lookup_name(sr, sr->user_cr, SMB_CASE_SENSITIVE,
310 		    sr->tid_tree->t_snode, fqi->fq_dnode,
311 		    namebuf, &fqi->fq_fnode);
312 		if (rc != 0)
313 			break;
314 
315 		if (smb_delete_check_dosattr(sr, err) != 0) {
316 			smb_node_release(fqi->fq_fnode);
317 			if (err->status == NT_STATUS_CANNOT_DELETE) {
318 				smb_odir_close(od);
319 				smb_odir_release(od);
320 				return (-1);
321 			}
322 			if ((err->status == NT_STATUS_FILE_IS_A_DIRECTORY) &&
323 			    (SMB_SEARCH_DIRECTORY(fqi->fq_sattr) != 0))
324 				break;
325 			continue;
326 		}
327 
328 		if (smb_delete_remove_file(sr, err) == 0) {
329 			++deleted;
330 			smb_node_release(fqi->fq_fnode);
331 			continue;
332 		}
333 		if (err->status == NT_STATUS_OBJECT_NAME_NOT_FOUND) {
334 			smb_node_release(fqi->fq_fnode);
335 			continue;
336 		}
337 
338 		smb_odir_close(od);
339 		smb_odir_release(od);
340 		smb_node_release(fqi->fq_fnode);
341 		return (-1);
342 	}
343 
344 	smb_odir_close(od);
345 	smb_odir_release(od);
346 
347 	if ((rc != 0) && (rc != ENOENT)) {
348 		smbsr_map_errno(rc, err);
349 		return (-1);
350 	}
351 
352 	if (deleted == 0) {
353 		smb_delete_error(err, NT_STATUS_NO_SUCH_FILE,
354 		    ERRDOS, ERROR_FILE_NOT_FOUND);
355 		return (-1);
356 	}
357 
358 	return (0);
359 }
360 
361 /*
362  * smb_delete_find_fname
363  *
364  * Find next filename that matches search pattern and return it
365  * in namebuf.
366  *
367  * Returns: 0 - success
368  *          errno
369  */
370 static int
371 smb_delete_find_fname(smb_request_t *sr, smb_odir_t *od, char *namebuf, int len)
372 {
373 	int		rc;
374 	smb_odirent_t	*odirent;
375 	boolean_t	eos;
376 
377 	odirent = kmem_alloc(sizeof (smb_odirent_t), KM_SLEEP);
378 
379 	rc = smb_odir_read(sr, od, odirent, &eos);
380 	if (rc == 0) {
381 		(void) strlcpy(namebuf, odirent->od_name, len);
382 	}
383 	kmem_free(odirent, sizeof (smb_odirent_t));
384 	return (rc);
385 }
386 
387 /*
388  * smb_delete_check_dosattr
389  *
390  * Check file's dos atributes to ensure that
391  * 1. the file is not a directory - NT_STATUS_FILE_IS_A_DIRECTORY
392  * 2. the file is not readonly - NT_STATUS_CANNOT_DELETE
393  * 3. the file's dos attributes comply with the specified search attributes
394  *     If the file is either hidden or system and those attributes
395  *     are not specified in the search attributes - NT_STATUS_NO_SUCH_FILE
396  *
397  * Returns: 0 - file's attributes pass all checks
398  *         -1 - err populated with error details
399  */
400 static int
401 smb_delete_check_dosattr(smb_request_t *sr, smb_error_t *err)
402 {
403 	smb_fqi_t *fqi;
404 	smb_node_t *node;
405 	smb_attr_t attr;
406 	uint16_t sattr;
407 
408 	fqi = &sr->arg.dirop.fqi;
409 	sattr = fqi->fq_sattr;
410 	node = fqi->fq_fnode;
411 
412 	bzero(&attr, sizeof (attr));
413 	attr.sa_mask = SMB_AT_DOSATTR;
414 	if (smb_node_getattr(sr, node, zone_kcred(), NULL, &attr) != 0) {
415 		smb_delete_error(err, NT_STATUS_INTERNAL_ERROR,
416 		    ERRDOS, ERROR_INTERNAL_ERROR);
417 		return (-1);
418 	}
419 
420 	if (attr.sa_dosattr & FILE_ATTRIBUTE_DIRECTORY) {
421 		smb_delete_error(err, NT_STATUS_FILE_IS_A_DIRECTORY,
422 		    ERRDOS, ERROR_ACCESS_DENIED);
423 		return (-1);
424 	}
425 
426 	if (SMB_PATHFILE_IS_READONLY(sr, node)) {
427 		smb_delete_error(err, NT_STATUS_CANNOT_DELETE,
428 		    ERRDOS, ERROR_ACCESS_DENIED);
429 		return (-1);
430 	}
431 
432 	if ((attr.sa_dosattr & FILE_ATTRIBUTE_HIDDEN) &&
433 	    !(SMB_SEARCH_HIDDEN(sattr))) {
434 		smb_delete_error(err, NT_STATUS_NO_SUCH_FILE,
435 		    ERRDOS, ERROR_FILE_NOT_FOUND);
436 		return (-1);
437 	}
438 
439 	if ((attr.sa_dosattr & FILE_ATTRIBUTE_SYSTEM) &&
440 	    !(SMB_SEARCH_SYSTEM(sattr))) {
441 		smb_delete_error(err, NT_STATUS_NO_SUCH_FILE,
442 		    ERRDOS, ERROR_FILE_NOT_FOUND);
443 		return (-1);
444 	}
445 
446 	return (0);
447 }
448 
449 /*
450  * smb_delete_remove_file
451  *
452  * For consistency with Windows 2000, the range check should be done
453  * after checking for sharing violations.  Attempting to delete a
454  * locked file will result in sharing violation, which is the same
455  * thing that will happen if you try to delete a non-locked open file.
456  *
457  * Note that windows 2000 rejects lock requests on open files that
458  * have been opened with metadata open modes.  The error is
459  * STATUS_ACCESS_DENIED.
460  *
461  * NT does not always close a file immediately, which can cause the
462  * share and access checking to fail (the node refcnt is greater
463  * than one), and the file doesn't get deleted. Breaking the oplock
464  * before share and lock checking gives the client a chance to
465  * close the file.
466  *
467  * Returns: 0 - success
468  *         -1 - error, err populated with error details
469  */
470 static int
471 smb_delete_remove_file(smb_request_t *sr, smb_error_t *err)
472 {
473 	int rc, count;
474 	uint32_t status;
475 	smb_fqi_t *fqi;
476 	smb_node_t *node;
477 	uint32_t flags = 0;
478 
479 	fqi = &sr->arg.dirop.fqi;
480 	node = fqi->fq_fnode;
481 
482 	/*
483 	 * Break BATCH oplock before ofile checks. If a client
484 	 * has a file open, this will force a flush or close,
485 	 * which may affect the outcome of any share checking.
486 	 */
487 	(void) smb_oplock_break(sr, node,
488 	    SMB_OPLOCK_BREAK_TO_LEVEL_II | SMB_OPLOCK_BREAK_BATCH);
489 
490 	/*
491 	 * Wait (a little) for the oplock break to be
492 	 * responded to by clients closing handles.
493 	 * Hold node->n_lock as reader to keep new
494 	 * ofiles from showing up after we check.
495 	 */
496 	smb_node_rdlock(node);
497 	for (count = 0; count <= 12; count++) {
498 		status = smb_node_delete_check(node);
499 		if (status != NT_STATUS_SHARING_VIOLATION)
500 			break;
501 		smb_node_unlock(node);
502 		delay(MSEC_TO_TICK(100));
503 		smb_node_rdlock(node);
504 	}
505 	if (status != NT_STATUS_SUCCESS) {
506 		smb_delete_error(err, NT_STATUS_SHARING_VIOLATION,
507 		    ERRDOS, ERROR_SHARING_VIOLATION);
508 		smb_node_unlock(node);
509 		return (-1);
510 	}
511 
512 	/*
513 	 * Note, the combination of these two:
514 	 *	smb_node_rdlock(node);
515 	 *	nbl_start_crit(node->vp, RW_READER);
516 	 * is equivalent to this call:
517 	 *	smb_node_start_crit(node, RW_READER)
518 	 *
519 	 * Cleanup after this point should use:
520 	 *	smb_node_end_crit(node)
521 	 */
522 	nbl_start_crit(node->vp, RW_READER);
523 
524 	/*
525 	 * This checks nbl_share_conflict, nbl_lock_conflict
526 	 */
527 	status = smb_nbl_conflict(node, 0, UINT64_MAX, NBL_REMOVE);
528 	if (status == NT_STATUS_SHARING_VIOLATION) {
529 		smb_node_end_crit(node);
530 		smb_delete_error(err, NT_STATUS_SHARING_VIOLATION,
531 		    ERRDOS, ERROR_SHARING_VIOLATION);
532 		return (-1);
533 	}
534 	if (status != NT_STATUS_SUCCESS) {
535 		smb_node_end_crit(node);
536 		smb_delete_error(err, NT_STATUS_ACCESS_DENIED,
537 		    ERRDOS, ERROR_ACCESS_DENIED);
538 		return (-1);
539 	}
540 
541 	if (SMB_TREE_SUPPORTS_CATIA(sr))
542 		flags |= SMB_CATIA;
543 
544 	rc = smb_fsop_remove(sr, sr->user_cr, node->n_dnode,
545 	    node->od_name, flags);
546 	if (rc != 0) {
547 		if (rc == ENOENT)
548 			smb_delete_error(err, NT_STATUS_OBJECT_NAME_NOT_FOUND,
549 			    ERRDOS, ERROR_FILE_NOT_FOUND);
550 		else
551 			smbsr_map_errno(rc, err);
552 
553 		smb_node_end_crit(node);
554 		return (-1);
555 	}
556 
557 	smb_node_end_crit(node);
558 	return (0);
559 }
560 
561 
562 /*
563  * smb_delete_check_path
564  *
565  * smb_pathname_validate() should already have been used to
566  * perform initial validation on the pathname. Additional
567  * request specific validation of the filename is performed
568  * here.
569  *
570  * - pn->pn_fname is NULL should result in NT_STATUS_FILE_IS_A_DIRECTORY
571  *
572  * - Any wildcard filename that resolves to '.' should result in
573  *   NT_STATUS_OBJECT_NAME_INVALID if the search attributes include
574  *   FILE_ATTRIBUTE_DIRECTORY
575  *
576  * Returns:
577  *   0: path is valid.
578  *  -1: path is invalid. Sets error information in sr.
579  */
580 static int
581 smb_delete_check_path(smb_request_t *sr)
582 {
583 	smb_fqi_t *fqi = &sr->arg.dirop.fqi;
584 	smb_pathname_t *pn = &fqi->fq_path;
585 
586 	if (pn->pn_fname == NULL) {
587 		smbsr_error(sr, NT_STATUS_FILE_IS_A_DIRECTORY,
588 		    ERRDOS, ERROR_ACCESS_DENIED);
589 		return (-1);
590 	}
591 
592 	/* fname component is, or resolves to, '.' (dot) */
593 	if ((strcmp(pn->pn_fname, ".") == 0) ||
594 	    (SMB_SEARCH_DIRECTORY(fqi->fq_sattr) &&
595 	    (smb_match(pn->pn_fname, ".", B_FALSE)))) {
596 		smbsr_error(sr, NT_STATUS_OBJECT_NAME_INVALID,
597 		    ERRDOS, ERROR_INVALID_NAME);
598 		return (-1);
599 	}
600 
601 	return (0);
602 }
603 
604 /*
605  * smb_delete_error
606  */
607 static void
608 smb_delete_error(smb_error_t *err,
609     uint32_t status, uint16_t errcls, uint16_t errcode)
610 {
611 	err->status = status;
612 	err->errcls = errcls;
613 	err->errcode = errcode;
614 }
615