xref: /illumos-gate/usr/src/uts/common/fs/smbsrv/smb_delete.c (revision 1b8adde7ba7d5e04395c141c5400dc2cffd7d809)
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  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <smbsrv/smb_incl.h>
27 #include <smbsrv/smb_fsops.h>
28 #include <smbsrv/smbinfo.h>
29 #include <sys/nbmlock.h>
30 
31 static int smb_delete_check_path(smb_request_t *, boolean_t *);
32 static int smb_delete_single_file(smb_request_t *, smb_error_t *);
33 static int smb_delete_multiple_files(smb_request_t *, smb_error_t *);
34 static int smb_delete_find_fname(smb_request_t *, uint32_t *);
35 static int smb_delete_check_attr(smb_request_t *, smb_error_t *);
36 static int smb_delete_remove_file(smb_request_t *, smb_error_t *);
37 
38 static void smb_delete_error(smb_error_t *, uint32_t, uint16_t, uint16_t);
39 
40 /*
41  * smb_com_delete
42  *
43  * The delete file message is sent to delete a data file. The appropriate
44  * Tid and additional pathname are passed. Read only files may not be
45  * deleted, the read-only attribute must be reset prior to file deletion.
46  *
47  * NT supports a hidden permission known as File Delete Child (FDC). If
48  * the user has FullControl access to a directory, the user is permitted
49  * to delete any object in the directory regardless of the permissions
50  * on the object.
51  *
52  * Client Request                     Description
53  * ================================== =================================
54  * UCHAR WordCount;                   Count of parameter words = 1
55  * USHORT SearchAttributes;
56  * USHORT ByteCount;                  Count of data bytes; min = 2
57  * UCHAR BufferFormat;                0x04
58  * STRING FileName[];                 File name
59  *
60  * Multiple files may be deleted in response to a single request as
61  * SMB_COM_DELETE supports wildcards
62  *
63  * SearchAttributes indicates the attributes that the target file(s) must
64  * have. If the attribute is zero then only normal files are deleted. If
65  * the system file or hidden attributes are specified then the delete is
66  * inclusive -both the specified type(s) of files and normal files are
67  * deleted. Attributes are described in the "Attribute Encoding" section
68  * of this document.
69  *
70  * If bit0 of the Flags2 field of the SMB header is set, a pattern is
71  * passed in, and the file has a long name, then the passed pattern  much
72  * match the long file name for the delete to succeed. If bit0 is clear, a
73  * pattern is passed in, and the file has a long name, then the passed
74  * pattern must match the file's short name for the deletion to succeed.
75  *
76  * Server Response                    Description
77  * ================================== =================================
78  * UCHAR WordCount;                   Count of parameter words = 0
79  * USHORT ByteCount;                  Count of data bytes = 0
80  *
81  * 4.2.10.1  Errors
82  *
83  * ERRDOS/ERRbadpath
84  * ERRDOS/ERRbadfile
85  * ERRDOS/ERRnoaccess
86  * ERRDOS/ERRbadshare	# returned by NT for files that are already open
87  * ERRHRD/ERRnowrite
88  * ERRSRV/ERRaccess
89  * ERRSRV/ERRinvdevice
90  * ERRSRV/ERRinvid
91  * ERRSRV/ERRbaduid
92  */
93 smb_sdrc_t
94 smb_pre_delete(smb_request_t *sr)
95 {
96 	int rc;
97 	smb_fqi_t *fqi;
98 
99 	fqi = &sr->arg.dirop.fqi;
100 
101 	if ((rc = smbsr_decode_vwv(sr, "w", &fqi->srch_attr)) == 0)
102 		rc = smbsr_decode_data(sr, "%S", sr, &fqi->path);
103 
104 	DTRACE_SMB_2(op__Delete__start, smb_request_t *, sr, smb_fqi_t *, fqi);
105 
106 	return ((rc == 0) ? SDRC_SUCCESS : SDRC_ERROR);
107 }
108 
109 void
110 smb_post_delete(smb_request_t *sr)
111 {
112 	DTRACE_SMB_1(op__Delete__done, smb_request_t *, sr);
113 }
114 
115 /*
116  * smb_com_delete
117  *
118  * 1. pre-process pathname -  smb_delete_check_path()
119  *    checks dot, bad path syntax, wildcards in path
120  *
121  * 2. process the path to get directory node & last_comp,
122  *    store these in fqi
123  *    - If smb_pathname_reduce cannot find the specified path,
124  *      the error (ENOTDIR) is translated to NT_STATUS_OBJECT_PATH_NOT_FOUND
125  *      if the target is a single file (no wildcards).  If there are
126  *      wildcards in the last_comp, NT_STATUS_OBJECT_NAME_NOT_FOUND is
127  *      used instead.
128  *    - If the directory node is the mount point and the last component
129  *      is ".." NT_STATUS_OBJECT_PATH_SYNTAX_BAD is returned.
130  *
131  * 3. check access permissions
132  *
133  * 4. invoke the appropriate deletion routine to find and remove
134  *    the specified file(s).
135  *    - if target is a single file (no wildcards) - smb_delete_single_file
136  *    - if the target contains wildcards - smb_delete_multiple_files
137  *
138  * Returns: SDRC_SUCCESS or SDRC_ERROR
139  */
140 smb_sdrc_t
141 smb_com_delete(smb_request_t *sr)
142 {
143 	int rc;
144 	smb_error_t err;
145 	uint32_t status;
146 	boolean_t wildcards;
147 	smb_fqi_t *fqi;
148 
149 	fqi = &sr->arg.dirop.fqi;
150 
151 	if (smb_delete_check_path(sr, &wildcards) != 0)
152 		return (SDRC_ERROR);
153 
154 	rc = smb_pathname_reduce(sr, sr->user_cr, fqi->path,
155 	    sr->tid_tree->t_snode, sr->tid_tree->t_snode,
156 	    &fqi->dir_snode, fqi->last_comp);
157 	if (rc == 0) {
158 		if (fqi->dir_snode->vp->v_type != VDIR) {
159 			smb_node_release(fqi->dir_snode);
160 			rc = ENOTDIR;
161 		}
162 	}
163 	if (rc != 0) {
164 		if (rc == ENOTDIR) {
165 			if (wildcards)
166 				status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
167 			else
168 				status = NT_STATUS_OBJECT_PATH_NOT_FOUND;
169 			smbsr_error(sr, status, ERRDOS, ERROR_FILE_NOT_FOUND);
170 		} else {
171 			smbsr_errno(sr, rc);
172 		}
173 
174 		return (SDRC_ERROR);
175 	}
176 
177 	if ((fqi->dir_snode == sr->tid_tree->t_snode) &&
178 	    (strcmp(fqi->last_comp, "..") == 0)) {
179 		smb_node_release(fqi->dir_snode);
180 		smbsr_error(sr, NT_STATUS_OBJECT_PATH_SYNTAX_BAD,
181 		    ERRDOS, ERROR_BAD_PATHNAME);
182 		return (SDRC_ERROR);
183 	}
184 
185 	rc = smb_fsop_access(sr, sr->user_cr, fqi->dir_snode,
186 	    FILE_LIST_DIRECTORY);
187 	if (rc != 0) {
188 		smb_node_release(fqi->dir_snode);
189 		smbsr_error(sr, NT_STATUS_ACCESS_DENIED,
190 		    ERRDOS, ERROR_ACCESS_DENIED);
191 		return (SDRC_ERROR);
192 	}
193 
194 	if (wildcards)
195 		rc = smb_delete_multiple_files(sr, &err);
196 	else
197 		rc = smb_delete_single_file(sr, &err);
198 
199 	smb_node_release(fqi->dir_snode);
200 
201 	if (rc != 0)
202 		smbsr_set_error(sr, &err);
203 	else
204 		rc = smbsr_encode_empty_result(sr);
205 
206 	return (rc == 0 ? SDRC_SUCCESS : SDRC_ERROR);
207 }
208 
209 /*
210  * smb_delete_single_file
211  *
212  * Find the specified file and, if its attributes match the search
213  * criteria, delete it.
214  *
215  * Returns 0 - success (file deleted)
216  *        -1 - error, err is populated with error details
217  */
218 static int
219 smb_delete_single_file(smb_request_t *sr, smb_error_t *err)
220 {
221 	smb_fqi_t *fqi;
222 	smb_attr_t ret_attr;
223 
224 	fqi = &sr->arg.dirop.fqi;
225 
226 	if (smb_fsop_lookup_name(sr, sr->user_cr, 0, sr->tid_tree->t_snode,
227 	    fqi->dir_snode, fqi->last_comp, &fqi->last_snode, &ret_attr) != 0) {
228 		smb_delete_error(err, NT_STATUS_OBJECT_NAME_NOT_FOUND,
229 		    ERRDOS, ERROR_FILE_NOT_FOUND);
230 		return (-1);
231 	}
232 
233 	if (smb_delete_check_attr(sr, err) != 0) {
234 		smb_node_release(fqi->last_snode);
235 		return (-1);
236 	}
237 
238 	if (smb_delete_remove_file(sr, err) != 0) {
239 		smb_node_release(fqi->last_snode);
240 		return (-1);
241 	}
242 
243 	smb_node_release(fqi->last_snode);
244 	return (0);
245 }
246 
247 /*
248  * smb_delete_multiple_files
249  *
250  * For each matching file found by smb_delete_find_name:
251  * 1. lookup file
252  * 2. check the file's attributes
253  *    - The search ends with an error if a readonly file
254  *      (NT_STATUS_CANNOT_DELETE) is matched.
255  *    - The search ends (but not an error) if a directory is
256  *      matched and the request's search did not include
257  *      directories.
258  *    - Otherwise, if smb_delete_check_attr fails the file
259  *      is skipped and the search continues (at step 1)
260  * 3. delete the file
261  *
262  * Returns 0 - success
263  *        -1 - error, err is populated with error details
264  */
265 static int
266 smb_delete_multiple_files(smb_request_t *sr, smb_error_t *err)
267 {
268 	int rc, deleted = 0;
269 	uint32_t cookie = 0;
270 	smb_fqi_t *fqi;
271 	smb_attr_t ret_attr;
272 
273 	fqi = &sr->arg.dirop.fqi;
274 
275 	for (;;) {
276 		rc = smb_delete_find_fname(sr, &cookie);
277 		if (rc != 0)
278 			break;
279 
280 		rc = smb_fsop_lookup_name(sr, sr->user_cr, 0,
281 		    sr->tid_tree->t_snode, fqi->dir_snode,
282 		    fqi->last_comp_od, &fqi->last_snode, &ret_attr);
283 		if (rc != 0)
284 			break;
285 
286 		if (smb_delete_check_attr(sr, err) != 0) {
287 			smb_node_release(fqi->last_snode);
288 			if (err->status == NT_STATUS_CANNOT_DELETE) {
289 				return (-1);
290 			}
291 			if ((err->status == NT_STATUS_FILE_IS_A_DIRECTORY) &&
292 			    (SMB_SEARCH_DIRECTORY(fqi->srch_attr) != 0))
293 				break;
294 			continue;
295 		}
296 
297 		if (smb_delete_remove_file(sr, err) == 0) {
298 			++deleted;
299 			smb_node_release(fqi->last_snode);
300 			continue;
301 		}
302 		if (err->status == NT_STATUS_OBJECT_NAME_NOT_FOUND) {
303 			smb_node_release(fqi->last_snode);
304 			continue;
305 		}
306 
307 		smb_node_release(fqi->last_snode);
308 		return (-1);
309 	}
310 
311 
312 	if ((rc != 0) && (rc != ENOENT)) {
313 		smbsr_map_errno(rc, err);
314 		return (-1);
315 	}
316 
317 	if (deleted == 0) {
318 		smb_delete_error(err, NT_STATUS_NO_SUCH_FILE,
319 		    ERRDOS, ERROR_FILE_NOT_FOUND);
320 		return (-1);
321 	}
322 
323 	return (0);
324 }
325 
326 /*
327  * smb_delete_find_fname
328  *
329  * Find next filename that matches search pattern (fqi->last_comp)
330  * and save it in fqi->last_comp_od.
331  *
332  * Returns: 0 - success
333  *          errno
334  */
335 static int
336 smb_delete_find_fname(smb_request_t *sr, uint32_t *cookie)
337 {
338 	int rc, n_name;
339 	ino64_t fileid;
340 	smb_fqi_t *fqi;
341 	char name83[SMB_SHORTNAMELEN];
342 	char shortname[SMB_SHORTNAMELEN];
343 	boolean_t ignore_case;
344 
345 	fqi = &sr->arg.dirop.fqi;
346 
347 	ignore_case = SMB_TREE_IS_CASEINSENSITIVE(sr);
348 
349 	for (;;) {
350 		n_name = sizeof (fqi->last_comp_od)  - 1;
351 
352 		rc = smb_fsop_readdir(sr, sr->user_cr, fqi->dir_snode, cookie,
353 		    fqi->last_comp_od, &n_name, &fileid, NULL, NULL, NULL);
354 
355 		if (rc != 0)
356 			return (rc);
357 
358 		/* check for EOF */
359 		if (n_name == 0)
360 			return (ENOENT);
361 
362 		fqi->last_comp_od[n_name] = '\0';
363 
364 		if (smb_match_name(fileid, fqi->last_comp_od, shortname, name83,
365 		    fqi->last_comp, ignore_case))
366 			return (0);
367 	}
368 }
369 
370 /*
371  * smb_delete_check_attr
372  *
373  * Check file's dos atributes to ensure that
374  * 1. the file is not a directory - NT_STATUS_FILE_IS_A_DIRECTORY
375  * 2. the file is not readonly - NT_STATUS_CANNOT_DELETE
376  * 3. the file's dos attributes comply with the specified search attributes
377  *     If the file is either hidden or system and those attributes
378  *     are not specified in the search attributes - NT_STATUS_NO_SUCH_FILE
379  *
380  * Returns: 0 - file's attributes pass all checks
381  *         -1 - err populated with error details
382  */
383 static int
384 smb_delete_check_attr(smb_request_t *sr, smb_error_t *err)
385 {
386 	smb_fqi_t *fqi;
387 	smb_node_t *node;
388 	uint16_t dosattr, sattr;
389 
390 	fqi = &sr->arg.dirop.fqi;
391 	sattr = fqi->srch_attr;
392 	node = fqi->last_snode;
393 	dosattr = smb_node_get_dosattr(node);
394 
395 	if (dosattr & FILE_ATTRIBUTE_DIRECTORY) {
396 		smb_delete_error(err, NT_STATUS_FILE_IS_A_DIRECTORY,
397 		    ERRDOS, ERROR_ACCESS_DENIED);
398 		return (-1);
399 	}
400 
401 	if (SMB_PATHFILE_IS_READONLY(sr, node)) {
402 		smb_delete_error(err, NT_STATUS_CANNOT_DELETE,
403 		    ERRDOS, ERROR_ACCESS_DENIED);
404 		return (-1);
405 	}
406 
407 	if ((dosattr & FILE_ATTRIBUTE_HIDDEN) && !(SMB_SEARCH_HIDDEN(sattr))) {
408 		smb_delete_error(err, NT_STATUS_NO_SUCH_FILE,
409 		    ERRDOS, ERROR_FILE_NOT_FOUND);
410 		return (-1);
411 	}
412 
413 	if ((dosattr & FILE_ATTRIBUTE_SYSTEM) && !(SMB_SEARCH_SYSTEM(sattr))) {
414 		smb_delete_error(err, NT_STATUS_NO_SUCH_FILE,
415 		    ERRDOS, ERROR_FILE_NOT_FOUND);
416 		return (-1);
417 	}
418 
419 	return (0);
420 }
421 
422 /*
423  * smb_delete_remove_file
424  *
425  * For consistency with Windows 2000, the range check should be done
426  * after checking for sharing violations.  Attempting to delete a
427  * locked file will result in sharing violation, which is the same
428  * thing that will happen if you try to delete a non-locked open file.
429  *
430  * Note that windows 2000 rejects lock requests on open files that
431  * have been opened with metadata open modes.  The error is
432  * STATUS_ACCESS_DENIED.
433  *
434  * NT does not always close a file immediately, which can cause the
435  * share and access checking to fail (the node refcnt is greater
436  * than one), and the file doesn't get deleted. Breaking the oplock
437  * before share and access checking gives the client a chance to
438  * close the file.
439  *
440  * Returns: 0 - success
441  *         -1 - error, err populated with error details
442  */
443 static int
444 smb_delete_remove_file(smb_request_t *sr, smb_error_t *err)
445 {
446 	int rc;
447 	uint32_t status;
448 	smb_fqi_t *fqi;
449 	smb_node_t *node;
450 
451 	fqi = &sr->arg.dirop.fqi;
452 	node = fqi->last_snode;
453 
454 	smb_oplock_break(node);
455 
456 	smb_node_start_crit(node, RW_READER);
457 
458 	status = smb_node_delete_check(node);
459 	if (status != NT_STATUS_SUCCESS) {
460 		smb_delete_error(err, NT_STATUS_SHARING_VIOLATION,
461 		    ERRDOS, ERROR_SHARING_VIOLATION);
462 		smb_node_end_crit(node);
463 		return (-1);
464 	}
465 
466 	status = smb_range_check(sr, node, 0, UINT64_MAX, B_TRUE);
467 	if (status != NT_STATUS_SUCCESS) {
468 		smb_delete_error(err, NT_STATUS_ACCESS_DENIED,
469 		    ERRDOS, ERROR_ACCESS_DENIED);
470 		smb_node_end_crit(node);
471 		return (-1);
472 	}
473 
474 	rc = smb_fsop_remove(sr, sr->user_cr, node->dir_snode,
475 	    node->od_name, 1);
476 	if (rc != 0) {
477 		if (rc == ENOENT)
478 			smb_delete_error(err, NT_STATUS_OBJECT_NAME_NOT_FOUND,
479 			    ERRDOS, ERROR_FILE_NOT_FOUND);
480 		else
481 			smbsr_map_errno(rc, err);
482 
483 		smb_node_end_crit(node);
484 		return (-1);
485 	}
486 
487 	smb_node_end_crit(node);
488 	return (0);
489 }
490 
491 
492 /*
493  * smb_delete_check_path
494  *
495  * Perform initial validation on the pathname and last_comp.
496  *
497  * wildcards in path:
498  * Wildcards in the path (excluding the last_comp) should result
499  * in NT_STATUS_OBJECT_NAME_INVALID.
500  *
501  * bad path syntax:
502  * On unix .. at the root of a file system links to the root. Thus
503  * an attempt to lookup "/../../.." will be the same as looking up "/"
504  * CIFs clients expect the above to result in
505  * NT_STATUS_OBJECT_PATH_SYNTAX_BAD. It is currently not possible
506  * (and questionable if it's desirable) to deal with all cases
507  * but paths beginning with \\.. are handled. See bad_paths[].
508  * Cases like "\\dir\\..\\.." will be caught and handled after the
509  * pnreduce.  Cases like "\\dir\\..\\..\\filename" will still result
510  * in "\\filename" which is contrary to windows behavior.
511  *
512  * dot:
513  * A filename of '.' should result in NT_STATUS_OBJECT_NAME_INVALID
514  * Any wildcard filename that resolves to '.' should result in
515  * NT_STATUS_OBJECT_NAME_INVALID if the search attributes include
516  * FILE_ATTRIBUTE_DIRECTORY
517  *
518  * Returns:
519  *   0:  path is valid. Sets *wildcard to TRUE if wildcard delete
520  *	         i.e. if wildcards in last component
521  *  -1: path is invalid. Sets error information in sr.
522  */
523 static int
524 smb_delete_check_path(smb_request_t *sr, boolean_t *wildcard)
525 {
526 	smb_fqi_t *fqi = &sr->arg.dirop.fqi;
527 	char *p, *last_comp;
528 	int i, wildcards;
529 
530 	struct {
531 		char *name;
532 		int len;
533 	} *bad, bad_paths[] = {
534 		{"\\..\0", 4},
535 		{"\\..\\", 4},
536 		{"..\0", 3},
537 		{"..\\", 3}
538 	};
539 
540 	/* check for wildcards in path */
541 	wildcards = smb_convert_unicode_wildcards(fqi->path);
542 
543 	/* find last component, strip trailing '\\' */
544 	p = fqi->path + strlen(fqi->path) - 1;
545 	while (*p == '\\') {
546 		*p = '\0';
547 		--p;
548 	}
549 	if ((p = strrchr(fqi->path, '\\')) == NULL) {
550 		last_comp = fqi->path;
551 	} else {
552 		last_comp = ++p;
553 
554 		/* wildcards in path > wildcards in last_comp */
555 		if (smb_convert_unicode_wildcards(last_comp) != wildcards) {
556 			smbsr_error(sr, NT_STATUS_OBJECT_NAME_INVALID,
557 			    ERRDOS, ERROR_INVALID_NAME);
558 			return (-1);
559 		}
560 	}
561 
562 	/* path above the mount point */
563 	for (i = 0; i < sizeof (bad_paths) / sizeof (bad_paths[0]); ++i) {
564 		bad = &bad_paths[i];
565 		if (strncmp(fqi->path, bad->name, bad->len) == 0) {
566 			smbsr_error(sr, NT_STATUS_OBJECT_PATH_SYNTAX_BAD,
567 			    ERRDOS, ERROR_BAD_PATHNAME);
568 			return (-1);
569 		}
570 	}
571 
572 	/* last component is, or resolves to, '.' (dot) */
573 	if ((strcmp(last_comp, ".") == 0) ||
574 	    (SMB_SEARCH_DIRECTORY(fqi->srch_attr) &&
575 	    (smb_match(last_comp, ".")))) {
576 		smbsr_error(sr, NT_STATUS_OBJECT_NAME_INVALID,
577 		    ERRDOS, ERROR_INVALID_NAME);
578 		return (-1);
579 	}
580 
581 	*wildcard = (wildcards != 0);
582 	return (0);
583 }
584 
585 /*
586  * smb_delete_error
587  */
588 static void
589 smb_delete_error(smb_error_t *err,
590     uint32_t status, uint16_t errcls, uint16_t errcode)
591 {
592 	err->severity = ERROR_SEVERITY_ERROR;
593 	err->status = status;
594 	err->errcls = errcls;
595 	err->errcode = errcode;
596 }
597