xref: /illumos-gate/usr/src/uts/common/fs/smbsrv/smb_node.c (revision 7a088f03b431bdffa96c3b2175964d4d38420caa)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 /*
26  * SMB Node State Machine
27  * ----------------------
28  *
29  *
30  *		    +----------- Creation/Allocation
31  *		    |
32  *		    | T0
33  *		    |
34  *		    v
35  *    +----------------------------+        T1
36  *    |  SMB_NODE_STATE_AVAILABLE  |--------------------+
37  *    +----------------------------+			|
38  *		    |	     ^				|
39  *		    |	     |				v
40  *		    |	     |	  T2	+-------------------------------+
41  *		    |	     |<---------| SMB_NODE_STATE_OPLOCK_GRANTED |
42  *		    |	     |		+-------------------------------+
43  *		    | T5     |				|
44  *		    |	     |				| T3
45  *		    |	     |				v
46  *		    |	     |	  T4	+--------------------------------+
47  *		    |	     +----------| SMB_NODE_STATE_OPLOCK_BREAKING |
48  *		    |			+--------------------------------+
49  *		    |
50  *		    v
51  *    +-----------------------------+
52  *    |  SMB_NODE_STATE_DESTROYING  |
53  *    +-----------------------------+
54  *		    |
55  *		    |
56  *		    | T6
57  *		    |
58  *		    +----------> Deletion/Free
59  *
60  * Transition T0
61  *
62  *    This transition occurs in smb_node_lookup(). If the node looked for is
63  *    not found in the has table a new node is created. The reference count is
64  *    initialized to 1 and the state initialized to SMB_NODE_STATE_AVAILABLE.
65  *
66  * Transition T1
67  *
68  *    This transition occurs smb_oplock_acquire() during an OPEN.
69  *
70  * Transition T2
71  *
72  *    This transition occurs in smb_oplock_release(). The events triggering
73  *    it are:
74  *
75  *	- LockingAndX sent by the client that was granted the oplock.
76  *	- Closing of the file.
77  *
78  * Transition T3
79  *
80  *    This transition occurs in smb_oplock_break(). The events triggering
81  *    it are:
82  *
83  *	- Another client wants to open the file.
84  *	- A client is trying to delete the file.
85  *	- A client is trying to rename the file.
86  *	- A client is trying to set/modify  the file attributes.
87  *
88  * Transition T4
89  *
90  *    This transition occurs in smb_oplock_release or smb_oplock_break(). The
91  *    events triggering it are:
92  *
93  *	- The client that was granting the oplock releases it (close or
94  *	  LockingAndx).
95  *	- The time alloted to release the oplock expired.
96  *
97  * Transition T5
98  *
99  *    This transition occurs in smb_node_release(). If the reference count
100  *    drops to zero the state is moved to SMB_NODE_STATE_DESTROYING and no more
101  *    reference count will be given out for that node.
102  *
103  * Transition T6
104  *
105  *    This transition occurs in smb_node_release(). The structure is deleted.
106  *
107  * Comments
108  * --------
109  *
110  *    The reason the smb node has 2 states is the following synchronization
111  *    rule:
112  *
113  *    There's a mutex embedded in the node used to protect its fields and
114  *    there's a lock embedded in the bucket of the hash table the node belongs
115  *    to. To increment or to decrement the reference count the mutex must be
116  *    entered. To insert the node into the bucket and to remove it from the
117  *    bucket the lock must be entered in RW_WRITER mode. When both (mutex and
118  *    lock) have to be entered, the lock has always to be entered first then
119  *    the mutex. This prevents a deadlock between smb_node_lookup() and
120  *    smb_node_release() from occurring. However, in smb_node_release() when the
121  *    reference count drops to zero and triggers the deletion of the node, the
122  *    mutex has to be released before entering the lock of the bucket (to
123  *    remove the node). This creates a window during which the node that is
124  *    about to be freed could be given out by smb_node_lookup(). To close that
125  *    window the node is moved to the state SMB_NODE_STATE_DESTROYING before
126  *    releasing the mutex. That way, even if smb_node_lookup() finds it, the
127  *    state will indicate that the node should be treated as non existent (of
128  *    course the state of the node should be tested/updated under the
129  *    protection of the mutex).
130  */
131 #include <smbsrv/smb_incl.h>
132 #include <smbsrv/smb_fsops.h>
133 #include <smbsrv/smb_kstat.h>
134 #include <sys/pathname.h>
135 #include <sys/sdt.h>
136 #include <sys/nbmlock.h>
137 
138 uint32_t smb_is_executable(char *);
139 static void smb_node_delete_on_close(smb_node_t *);
140 static void smb_node_create_audit_buf(smb_node_t *, int);
141 static void smb_node_destroy_audit_buf(smb_node_t *);
142 static void smb_node_audit(smb_node_t *);
143 static smb_node_t *smb_node_alloc(char *, vnode_t *, smb_attr_t *,
144     smb_llist_t *bucket, uint32_t hashkey);
145 static void smb_node_free(smb_node_t *);
146 static int smb_node_constructor(void *, void *, int);
147 static void smb_node_destructor(void *, void *);
148 static smb_llist_t *smb_node_get_hash(fsid_t *, smb_attr_t *, uint32_t *);
149 
150 #define	VALIDATE_DIR_NODE(_dir_, _node_) \
151     ASSERT((_dir_)->n_magic == SMB_NODE_MAGIC); \
152     ASSERT(((_dir_)->vp->v_xattrdir) || ((_dir_)->vp->v_type == VDIR)); \
153     ASSERT((_dir_)->dir_snode != (_node_));
154 
155 static kmem_cache_t	*smb_node_cache = NULL;
156 static boolean_t	smb_node_initialized = B_FALSE;
157 static smb_llist_t	smb_node_hash_table[SMBND_HASH_MASK+1];
158 
159 /*
160  * smb_node_init
161  *
162  * Initialization of the SMB node layer.
163  *
164  * This function is not multi-thread safe. The caller must make sure only one
165  * thread makes the call.
166  */
167 int
168 smb_node_init(void)
169 {
170 	int	i;
171 
172 	if (smb_node_initialized)
173 		return (0);
174 	smb_node_cache = kmem_cache_create(SMBSRV_KSTAT_NODE_CACHE,
175 	    sizeof (smb_node_t), 8, smb_node_constructor, smb_node_destructor,
176 	    NULL, NULL, NULL, 0);
177 
178 	for (i = 0; i <= SMBND_HASH_MASK; i++) {
179 		smb_llist_constructor(&smb_node_hash_table[i],
180 		    sizeof (smb_node_t), offsetof(smb_node_t, n_lnd));
181 	}
182 	smb_node_initialized = B_TRUE;
183 	return (0);
184 }
185 
186 /*
187  * smb_node_fini
188  *
189  * This function is not multi-thread safe. The caller must make sure only one
190  * thread makes the call.
191  */
192 void
193 smb_node_fini(void)
194 {
195 	int	i;
196 
197 	if (!smb_node_initialized)
198 		return;
199 
200 #ifdef DEBUG
201 	for (i = 0; i <= SMBND_HASH_MASK; i++) {
202 		smb_node_t	*node;
203 
204 		/*
205 		 * The following sequence is just intended for sanity check.
206 		 * This will have to be modified when the code goes into
207 		 * production.
208 		 *
209 		 * The SMB node hash table should be emtpy at this point. If the
210 		 * hash table is not empty a panic will be triggered.
211 		 *
212 		 * The reason why SMB nodes are still remaining in the hash
213 		 * table is problably due to a mismatch between calls to
214 		 * smb_node_lookup() and smb_node_release(). You must track that
215 		 * down.
216 		 */
217 		node = smb_llist_head(&smb_node_hash_table[i]);
218 		ASSERT(node == NULL);
219 	}
220 #endif
221 
222 	for (i = 0; i <= SMBND_HASH_MASK; i++) {
223 		smb_llist_destructor(&smb_node_hash_table[i]);
224 	}
225 	kmem_cache_destroy(smb_node_cache);
226 	smb_node_cache = NULL;
227 	smb_node_initialized = B_FALSE;
228 }
229 
230 /*
231  * smb_node_lookup()
232  *
233  * NOTE: This routine should only be called by the file system interface layer,
234  * and not by SMB.
235  *
236  * smb_node_lookup() is called upon successful lookup, mkdir, and create
237  * (for both non-streams and streams).  In each of these cases, a held vnode is
238  * passed into this routine.  If a new smb_node is created it will take its
239  * own hold on the vnode.  The caller's hold therefore still belongs to, and
240  * should be released by, the caller.
241  *
242  * A reference is taken on the smb_node whether found in the hash table
243  * or newly created.
244  *
245  * If an smb_node needs to be created, a reference is also taken on the
246  * dir_snode (if passed in).
247  *
248  * See smb_node_release() for details on the release of these references.
249  */
250 
251 /*ARGSUSED*/
252 smb_node_t *
253 smb_node_lookup(
254     struct smb_request	*sr,
255     struct open_param	*op,
256     cred_t		*cred,
257     vnode_t		*vp,
258     char		*od_name,
259     smb_node_t		*dir_snode,
260     smb_node_t		*unnamed_node,
261     smb_attr_t		*attr)
262 {
263 	smb_llist_t		*node_hdr;
264 	smb_node_t		*node;
265 	uint32_t		hashkey = 0;
266 	fsid_t			fsid;
267 	int			error;
268 	krw_t			lock_mode;
269 	vnode_t			*unnamed_vp = NULL;
270 
271 	/*
272 	 * smb_vop_getattr() is called here instead of smb_fsop_getattr(),
273 	 * because the node may not yet exist.  We also do not want to call
274 	 * it with the list lock held.
275 	 */
276 
277 	if (unnamed_node)
278 		unnamed_vp = unnamed_node->vp;
279 
280 	/*
281 	 * This getattr is performed on behalf of the server
282 	 * that's why kcred is used not the user's cred
283 	 */
284 	attr->sa_mask = SMB_AT_ALL;
285 	error = smb_vop_getattr(vp, unnamed_vp, attr, 0, kcred);
286 	if (error)
287 		return (NULL);
288 
289 	if (sr && sr->tid_tree) {
290 		/*
291 		 * The fsid for a file is that of the tree, even
292 		 * if the file resides in a different mountpoint
293 		 * under the share.
294 		 */
295 		fsid = SMB_TREE_FSID(sr->tid_tree);
296 	} else {
297 		/*
298 		 * This should be getting executed only for the
299 		 * tree root smb_node.
300 		 */
301 		fsid = vp->v_vfsp->vfs_fsid;
302 	}
303 
304 	node_hdr = smb_node_get_hash(&fsid, attr, &hashkey);
305 	lock_mode = RW_READER;
306 
307 	smb_llist_enter(node_hdr, lock_mode);
308 	for (;;) {
309 		node = list_head(&node_hdr->ll_list);
310 		while (node) {
311 			ASSERT(node->n_magic == SMB_NODE_MAGIC);
312 			ASSERT(node->n_hash_bucket == node_hdr);
313 			if ((node->n_hashkey == hashkey) && (node->vp == vp)) {
314 				mutex_enter(&node->n_mutex);
315 				DTRACE_PROBE1(smb_node_lookup_hit,
316 				    smb_node_t *, node);
317 				switch (node->n_state) {
318 				case SMB_NODE_STATE_OPLOCK_GRANTED:
319 				case SMB_NODE_STATE_OPLOCK_BREAKING:
320 				case SMB_NODE_STATE_AVAILABLE:
321 					/* The node was found. */
322 					node->n_refcnt++;
323 					if ((node->dir_snode == NULL) &&
324 					    (dir_snode != NULL) &&
325 					    (strcmp(od_name, "..") != 0) &&
326 					    (strcmp(od_name, ".") != 0)) {
327 						VALIDATE_DIR_NODE(dir_snode,
328 						    node);
329 						node->dir_snode = dir_snode;
330 						smb_node_ref(dir_snode);
331 					}
332 					node->attr = *attr;
333 					node->n_size = attr->sa_vattr.va_size;
334 
335 					smb_node_audit(node);
336 					mutex_exit(&node->n_mutex);
337 					smb_llist_exit(node_hdr);
338 					return (node);
339 
340 				case SMB_NODE_STATE_DESTROYING:
341 					/*
342 					 * Although the node exists it is about
343 					 * to be destroyed. We act as it hasn't
344 					 * been found.
345 					 */
346 					mutex_exit(&node->n_mutex);
347 					break;
348 				default:
349 					/*
350 					 * Although the node exists it is in an
351 					 * unknown state. We act as it hasn't
352 					 * been found.
353 					 */
354 					ASSERT(0);
355 					mutex_exit(&node->n_mutex);
356 					break;
357 				}
358 			}
359 			node = smb_llist_next(node_hdr, node);
360 		}
361 		if ((lock_mode == RW_READER) && smb_llist_upgrade(node_hdr)) {
362 			lock_mode = RW_WRITER;
363 			continue;
364 		}
365 		break;
366 	}
367 	node = smb_node_alloc(od_name, vp, attr, node_hdr, hashkey);
368 	node->n_orig_uid = crgetuid(sr->user_cr);
369 
370 	if (op)
371 		node->flags |= smb_is_executable(op->fqi.last_comp);
372 
373 	if (dir_snode) {
374 		smb_node_ref(dir_snode);
375 		node->dir_snode = dir_snode;
376 		ASSERT(dir_snode->dir_snode != node);
377 		ASSERT((dir_snode->vp->v_xattrdir) ||
378 		    (dir_snode->vp->v_type == VDIR));
379 	}
380 
381 	if (unnamed_node) {
382 		smb_node_ref(unnamed_node);
383 		node->unnamed_stream_node = unnamed_node;
384 	}
385 
386 	DTRACE_PROBE1(smb_node_lookup_miss, smb_node_t *, node);
387 	smb_node_audit(node);
388 	smb_llist_insert_head(node_hdr, node);
389 	smb_llist_exit(node_hdr);
390 	return (node);
391 }
392 
393 /*
394  * smb_stream_node_lookup()
395  *
396  * Note: stream_name (the name that will be stored in the "od_name" field
397  * of a stream's smb_node) is the same as the on-disk name for the stream
398  * except that it does not have SMB_STREAM_PREFIX prepended.
399  */
400 
401 smb_node_t *
402 smb_stream_node_lookup(smb_request_t *sr, cred_t *cr, smb_node_t *fnode,
403     vnode_t *xattrdirvp, vnode_t *vp, char *stream_name, smb_attr_t *ret_attr)
404 {
405 	smb_node_t	*xattrdir_node;
406 	smb_node_t	*snode;
407 	smb_attr_t	tmp_attr;
408 
409 	xattrdir_node = smb_node_lookup(sr, NULL, cr, xattrdirvp, XATTR_DIR,
410 	    fnode, NULL, &tmp_attr);
411 
412 	if (xattrdir_node == NULL)
413 		return (NULL);
414 
415 	snode = smb_node_lookup(sr, NULL, cr, vp, stream_name, xattrdir_node,
416 	    fnode, ret_attr);
417 
418 	(void) smb_node_release(xattrdir_node);
419 	return (snode);
420 }
421 
422 
423 /*
424  * This function should be called whenever a reference is needed on an
425  * smb_node pointer.  The copy of an smb_node pointer from one non-local
426  * data structure to another requires a reference to be taken on the smb_node
427  * (unless the usage is localized).  Each data structure deallocation routine
428  * will call smb_node_release() on its smb_node pointers.
429  *
430  * In general, an smb_node pointer residing in a structure should never be
431  * stale.  A node pointer may be NULL, however, and care should be taken
432  * prior to calling smb_node_ref(), which ASSERTs that the pointer is valid.
433  * Care also needs to be taken with respect to racing deallocations of a
434  * structure.
435  */
436 void
437 smb_node_ref(smb_node_t *node)
438 {
439 	SMB_NODE_VALID(node);
440 
441 	mutex_enter(&node->n_mutex);
442 	switch (node->n_state) {
443 	case SMB_NODE_STATE_AVAILABLE:
444 	case SMB_NODE_STATE_OPLOCK_GRANTED:
445 	case SMB_NODE_STATE_OPLOCK_BREAKING:
446 		node->n_refcnt++;
447 		ASSERT(node->n_refcnt);
448 		DTRACE_PROBE1(smb_node_ref_exit, smb_node_t *, node);
449 		smb_node_audit(node);
450 		break;
451 	default:
452 		SMB_PANIC();
453 	}
454 	mutex_exit(&node->n_mutex);
455 }
456 
457 /*
458  * smb_node_lookup() takes a hold on an smb_node, whether found in the
459  * hash table or newly created.  This hold is expected to be released
460  * in the following manner.
461  *
462  * smb_node_lookup() takes an address of an smb_node pointer.  This should
463  * be getting passed down via a lookup (whether path name or component), mkdir,
464  * create.  If the original smb_node pointer resides in a data structure, then
465  * the deallocation routine for the data structure is responsible for calling
466  * smb_node_release() on the smb_node pointer.  Alternatively,
467  * smb_node_release() can be called as soon as the smb_node pointer is no longer
468  * needed.  In this case, callers are responsible for setting an embedded
469  * pointer to NULL if it is known that the last reference is being released.
470  *
471  * If the passed-in address of the smb_node pointer belongs to a local variable,
472  * then the caller with the local variable should call smb_node_release()
473  * directly.
474  *
475  * smb_node_release() itself will call smb_node_release() on a node's dir_snode,
476  * as smb_node_lookup() takes a hold on dir_snode.
477  */
478 void
479 smb_node_release(smb_node_t *node)
480 {
481 	SMB_NODE_VALID(node);
482 
483 	mutex_enter(&node->n_mutex);
484 	ASSERT(node->n_refcnt);
485 	DTRACE_PROBE1(smb_node_release, smb_node_t *, node);
486 	if (--node->n_refcnt == 0) {
487 		switch (node->n_state) {
488 
489 		case SMB_NODE_STATE_AVAILABLE:
490 			node->n_state = SMB_NODE_STATE_DESTROYING;
491 			mutex_exit(&node->n_mutex);
492 
493 			smb_llist_enter(node->n_hash_bucket, RW_WRITER);
494 			smb_llist_remove(node->n_hash_bucket, node);
495 			smb_llist_exit(node->n_hash_bucket);
496 
497 			/*
498 			 * Check if the file was deleted
499 			 */
500 			smb_node_delete_on_close(node);
501 
502 			if (node->dir_snode) {
503 				ASSERT(node->dir_snode->n_magic ==
504 				    SMB_NODE_MAGIC);
505 				smb_node_release(node->dir_snode);
506 			}
507 
508 			if (node->unnamed_stream_node) {
509 				ASSERT(node->unnamed_stream_node->n_magic ==
510 				    SMB_NODE_MAGIC);
511 				smb_node_release(node->unnamed_stream_node);
512 			}
513 
514 			smb_node_free(node);
515 			return;
516 
517 		default:
518 			SMB_PANIC();
519 		}
520 	}
521 	smb_node_audit(node);
522 	mutex_exit(&node->n_mutex);
523 }
524 
525 static void
526 smb_node_delete_on_close(smb_node_t *node)
527 {
528 	smb_node_t	*d_snode;
529 	int		rc = 0;
530 
531 	d_snode = node->dir_snode;
532 	if (node->flags & NODE_FLAGS_DELETE_ON_CLOSE) {
533 
534 		node->flags &= ~NODE_FLAGS_DELETE_ON_CLOSE;
535 		ASSERT(node->od_name != NULL);
536 		if (node->attr.sa_vattr.va_type == VDIR)
537 			rc = smb_fsop_rmdir(0, node->delete_on_close_cred,
538 			    d_snode, node->od_name, 1);
539 		else
540 			rc = smb_fsop_remove(0, node->delete_on_close_cred,
541 			    d_snode, node->od_name, 1);
542 		smb_cred_rele(node->delete_on_close_cred);
543 	}
544 	if (rc != 0)
545 		cmn_err(CE_WARN, "File %s could not be removed, rc=%d\n",
546 		    node->od_name, rc);
547 	DTRACE_PROBE2(smb_node_delete_on_close, int, rc, smb_node_t *, node);
548 }
549 
550 /*
551  * smb_node_rename()
552  *
553  */
554 void
555 smb_node_rename(
556     smb_node_t	*from_dnode,
557     smb_node_t	*ret_node,
558     smb_node_t	*to_dnode,
559     char	*to_name)
560 {
561 	SMB_NODE_VALID(from_dnode);
562 	SMB_NODE_VALID(to_dnode);
563 	SMB_NODE_VALID(ret_node);
564 
565 	smb_node_ref(to_dnode);
566 	mutex_enter(&ret_node->n_mutex);
567 	switch (ret_node->n_state) {
568 	case SMB_NODE_STATE_AVAILABLE:
569 	case SMB_NODE_STATE_OPLOCK_GRANTED:
570 	case SMB_NODE_STATE_OPLOCK_BREAKING:
571 		ret_node->dir_snode = to_dnode;
572 		mutex_exit(&ret_node->n_mutex);
573 		ASSERT(to_dnode->dir_snode != ret_node);
574 		ASSERT((to_dnode->vp->v_xattrdir) ||
575 		    (to_dnode->vp->v_type == VDIR));
576 		smb_node_release(from_dnode);
577 		(void) strcpy(ret_node->od_name, to_name);
578 		/*
579 		 * XXX Need to update attributes?
580 		 */
581 		break;
582 	default:
583 		SMB_PANIC();
584 	}
585 }
586 
587 int
588 smb_node_root_init(vnode_t *vp, smb_server_t *sv, smb_node_t **root)
589 {
590 	smb_attr_t	va;
591 	int		error;
592 	uint32_t	hashkey;
593 	smb_llist_t	*node_hdr;
594 	smb_node_t	*node;
595 
596 	va.sa_mask = SMB_AT_ALL;
597 	error = smb_vop_getattr(vp, NULL, &va, 0, kcred);
598 	if (error) {
599 		VN_RELE(vp);
600 		return (error);
601 	}
602 
603 	node_hdr = smb_node_get_hash(&vp->v_vfsp->vfs_fsid, &va, &hashkey);
604 
605 	node = smb_node_alloc(ROOTVOL, vp, &va, node_hdr, hashkey);
606 
607 	sv->si_root_smb_node = node;
608 	smb_node_audit(node);
609 	smb_llist_enter(node_hdr, RW_WRITER);
610 	smb_llist_insert_head(node_hdr, node);
611 	smb_llist_exit(node_hdr);
612 	*root = node;
613 	return (0);
614 }
615 
616 /*
617  * smb_node_get_size
618  */
619 u_offset_t
620 smb_node_get_size(smb_node_t *node, smb_attr_t *attr)
621 {
622 	u_offset_t size;
623 
624 	if (attr->sa_vattr.va_type == VDIR)
625 		return (0);
626 
627 	mutex_enter(&node->n_mutex);
628 	if (node && (node->flags & NODE_FLAGS_SET_SIZE))
629 		size = node->n_size;
630 	else
631 		size = attr->sa_vattr.va_size;
632 	mutex_exit(&node->n_mutex);
633 	return (size);
634 }
635 
636 static int
637 timeval_cmp(timestruc_t *a, timestruc_t *b)
638 {
639 	if (a->tv_sec < b->tv_sec)
640 		return (-1);
641 	if (a->tv_sec > b->tv_sec)
642 		return (1);
643 	/* Seconds are equal compare tv_nsec */
644 	if (a->tv_nsec < b->tv_nsec)
645 		return (-1);
646 	return (a->tv_nsec > b->tv_nsec);
647 }
648 
649 /*
650  * smb_node_set_time
651  *
652  * This function will update the time stored in the node and
653  * set the appropriate flags. If there is nothing to update,
654  * the function will return without any updates.  The update
655  * is only in the node level and the attribute in the file system
656  * will be updated when client close the file.
657  */
658 void
659 smb_node_set_time(
660     smb_node_t	*node,
661     timestruc_t	*crtime,
662     timestruc_t	*mtime,
663     timestruc_t	*atime,
664     timestruc_t	*ctime,
665     uint_t	what)
666 {
667 	if (what == 0)
668 		return;
669 
670 	if ((what & SMB_AT_CRTIME && crtime == 0) ||
671 	    (what & SMB_AT_MTIME && mtime == 0) ||
672 	    (what & SMB_AT_ATIME && atime == 0) ||
673 	    (what & SMB_AT_CTIME && ctime == 0))
674 		return;
675 
676 	mutex_enter(&node->n_mutex);
677 
678 	if ((what & SMB_AT_CRTIME) &&
679 	    timeval_cmp((timestruc_t *)&node->attr.sa_crtime,
680 	    crtime) != 0) {
681 		node->what |= SMB_AT_CRTIME;
682 		node->attr.sa_crtime = *((timestruc_t *)crtime);
683 	}
684 
685 	if ((what & SMB_AT_MTIME) &&
686 	    timeval_cmp((timestruc_t *)&node->attr.sa_vattr.va_mtime,
687 	    mtime) != 0) {
688 		node->what |= SMB_AT_MTIME;
689 		node->attr.sa_vattr.va_mtime = *((timestruc_t *)mtime);
690 	}
691 
692 	if ((what & SMB_AT_ATIME) &&
693 	    timeval_cmp((timestruc_t *)&node->attr.sa_vattr.va_atime,
694 	    atime) != 0) {
695 			node->what |= SMB_AT_ATIME;
696 			node->attr.sa_vattr.va_atime = *((timestruc_t *)atime);
697 	}
698 
699 	/*
700 	 * The ctime handling is trickier. It has three scenarios.
701 	 * 1. Only ctime need to be set and it is the same as the ctime
702 	 *    stored in the node. (update not necessary)
703 	 * 2. The ctime is the same as the ctime stored in the node but
704 	 *    is not the only time need to be set. (update required)
705 	 * 3. The ctime need to be set and is not the same as the ctime
706 	 *    stored in the node. (update required)
707 	 * Unlike other time setting, the ctime needs to be set even when
708 	 * it is the same as the ctime in the node if there are other time
709 	 * needs to be set (#2). This will ensure the ctime not being
710 	 * updated when other times are being updated in the file system.
711 	 *
712 	 * Retained file rules:
713 	 *
714 	 * 1. Don't add SMB_AT_CTIME to node->what by default because the
715 	 *    request will be rejected by filesystem
716 	 * 2. 'what' SMB_AT_CTIME shouldn't be set for retained files, i.e.
717 	 *    any request for changing ctime on these files should have
718 	 *    been already rejected
719 	 */
720 	node->what |= SMB_AT_CTIME;
721 	if (what & SMB_AT_CTIME) {
722 		if ((what == SMB_AT_CTIME) &&
723 		    timeval_cmp((timestruc_t *)&node->attr.sa_vattr.va_ctime,
724 		    ctime) == 0) {
725 			node->what &= ~SMB_AT_CTIME;
726 		} else {
727 			gethrestime(&node->attr.sa_vattr.va_ctime);
728 		}
729 	} else {
730 		gethrestime(&node->attr.sa_vattr.va_ctime);
731 	}
732 	mutex_exit(&node->n_mutex);
733 }
734 
735 
736 timestruc_t *
737 smb_node_get_crtime(smb_node_t *node)
738 {
739 	return ((timestruc_t *)&node->attr.sa_crtime);
740 }
741 
742 timestruc_t *
743 smb_node_get_atime(smb_node_t *node)
744 {
745 	return ((timestruc_t *)&node->attr.sa_vattr.va_atime);
746 }
747 
748 timestruc_t *
749 smb_node_get_ctime(smb_node_t *node)
750 {
751 	return ((timestruc_t *)&node->attr.sa_vattr.va_ctime);
752 }
753 
754 timestruc_t *
755 smb_node_get_mtime(smb_node_t *node)
756 {
757 	return ((timestruc_t *)&node->attr.sa_vattr.va_mtime);
758 }
759 
760 /*
761  * smb_node_set_dosattr
762  *
763  * Parse the specified DOS attributes and, if they have been modified,
764  * update the node cache. This call should be followed by a
765  * smb_sync_fsattr() call to write the attribute changes to filesystem.
766  */
767 void
768 smb_node_set_dosattr(smb_node_t *node, uint32_t dosattr)
769 {
770 	uint32_t mode = dosattr & (FILE_ATTRIBUTE_ARCHIVE |
771 	    FILE_ATTRIBUTE_READONLY |
772 	    FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM);
773 
774 	mutex_enter(&node->n_mutex);
775 	if (node->attr.sa_dosattr != mode) {
776 		node->attr.sa_dosattr = mode;
777 		node->what |= SMB_AT_DOSATTR;
778 	}
779 	mutex_exit(&node->n_mutex);
780 }
781 
782 /*
783  * smb_node_get_dosattr()
784  *
785  * This function is used to provide clients with information as to whether
786  * the readonly bit is set.  Hence both the node attribute cache (which
787  * reflects the on-disk attributes) and node->readonly_creator (which
788  * reflects whether a readonly set is pending from a readonly create) are
789  * checked.  In the latter case, the readonly attribute should be visible to
790  * all clients even though the readonly creator fid is immune to the readonly
791  * bit until close.
792  */
793 
794 uint32_t
795 smb_node_get_dosattr(smb_node_t *node)
796 {
797 	uint32_t dosattr = node->attr.sa_dosattr;
798 
799 	if (node->readonly_creator)
800 		dosattr |= FILE_ATTRIBUTE_READONLY;
801 
802 	if (!dosattr)
803 		dosattr = FILE_ATTRIBUTE_NORMAL;
804 
805 	return (dosattr);
806 }
807 
808 int
809 smb_node_set_delete_on_close(smb_node_t *node, cred_t *cr)
810 {
811 	int	rc = -1;
812 
813 	mutex_enter(&node->n_mutex);
814 	if (!(node->attr.sa_dosattr & FILE_ATTRIBUTE_READONLY) &&
815 	    !(node->flags & NODE_FLAGS_DELETE_ON_CLOSE)) {
816 		crhold(cr);
817 		node->delete_on_close_cred = cr;
818 		node->flags |= NODE_FLAGS_DELETE_ON_CLOSE;
819 		rc = 0;
820 	}
821 	mutex_exit(&node->n_mutex);
822 	return (rc);
823 }
824 
825 void
826 smb_node_reset_delete_on_close(smb_node_t *node)
827 {
828 	mutex_enter(&node->n_mutex);
829 	if (node->flags & NODE_FLAGS_DELETE_ON_CLOSE) {
830 		node->flags &= ~NODE_FLAGS_DELETE_ON_CLOSE;
831 		crfree(node->delete_on_close_cred);
832 		node->delete_on_close_cred = NULL;
833 	}
834 	mutex_exit(&node->n_mutex);
835 }
836 
837 /*
838  * smb_node_open_check
839  *
840  * check file sharing rules for current open request
841  * against all existing opens for a file.
842  *
843  * Returns NT_STATUS_SHARING_VIOLATION if there is any
844  * sharing conflict, otherwise returns NT_STATUS_SUCCESS.
845  */
846 uint32_t
847 smb_node_open_check(
848     smb_node_t	*node,
849     cred_t	*cr,
850     uint32_t	desired_access,
851     uint32_t	share_access)
852 {
853 	smb_ofile_t *of;
854 	uint32_t status;
855 
856 	SMB_NODE_VALID(node);
857 
858 	smb_llist_enter(&node->n_ofile_list, RW_READER);
859 	of = smb_llist_head(&node->n_ofile_list);
860 	while (of) {
861 		status = smb_ofile_open_check(of, cr, desired_access,
862 		    share_access);
863 
864 		switch (status) {
865 		case NT_STATUS_INVALID_HANDLE:
866 		case NT_STATUS_SUCCESS:
867 			of = smb_llist_next(&node->n_ofile_list, of);
868 			break;
869 		default:
870 			ASSERT(status == NT_STATUS_SHARING_VIOLATION);
871 			smb_llist_exit(&node->n_ofile_list);
872 			return (status);
873 		}
874 	}
875 
876 	smb_llist_exit(&node->n_ofile_list);
877 	return (NT_STATUS_SUCCESS);
878 }
879 
880 uint32_t
881 smb_node_rename_check(smb_node_t *node)
882 {
883 	smb_ofile_t	*of;
884 	uint32_t	status;
885 
886 	SMB_NODE_VALID(node);
887 
888 	/*
889 	 * Intra-CIFS check
890 	 */
891 	smb_llist_enter(&node->n_ofile_list, RW_READER);
892 	of = smb_llist_head(&node->n_ofile_list);
893 	while (of) {
894 		status = smb_ofile_rename_check(of);
895 
896 		switch (status) {
897 		case NT_STATUS_INVALID_HANDLE:
898 		case NT_STATUS_SUCCESS:
899 			of = smb_llist_next(&node->n_ofile_list, of);
900 			break;
901 		default:
902 			ASSERT(status == NT_STATUS_SHARING_VIOLATION);
903 			smb_llist_exit(&node->n_ofile_list);
904 			return (status);
905 		}
906 	}
907 	smb_llist_exit(&node->n_ofile_list);
908 
909 	/*
910 	 * system-wide share check
911 	 */
912 	if (nbl_share_conflict(node->vp, NBL_RENAME, NULL))
913 		return (NT_STATUS_SHARING_VIOLATION);
914 	else
915 		return (NT_STATUS_SUCCESS);
916 }
917 
918 uint32_t
919 smb_node_delete_check(smb_node_t *node)
920 {
921 	smb_ofile_t	*of;
922 	uint32_t	status;
923 
924 	SMB_NODE_VALID(node);
925 
926 	if (node->attr.sa_vattr.va_type == VDIR)
927 		return (NT_STATUS_SUCCESS);
928 
929 	/*
930 	 * intra-CIFS check
931 	 */
932 	smb_llist_enter(&node->n_ofile_list, RW_READER);
933 	of = smb_llist_head(&node->n_ofile_list);
934 	while (of) {
935 		status = smb_ofile_delete_check(of);
936 
937 		switch (status) {
938 		case NT_STATUS_INVALID_HANDLE:
939 		case NT_STATUS_SUCCESS:
940 			of = smb_llist_next(&node->n_ofile_list, of);
941 			break;
942 		default:
943 			ASSERT(status == NT_STATUS_SHARING_VIOLATION);
944 			smb_llist_exit(&node->n_ofile_list);
945 			return (status);
946 		}
947 	}
948 	smb_llist_exit(&node->n_ofile_list);
949 
950 	/*
951 	 * system-wide share check
952 	 */
953 	if (nbl_share_conflict(node->vp, NBL_REMOVE, NULL))
954 		return (NT_STATUS_SHARING_VIOLATION);
955 	else
956 		return (NT_STATUS_SUCCESS);
957 }
958 
959 /*
960  * smb_node_start_crit()
961  *
962  * Enter critical region for share reservations.
963  * See comments above smb_fsop_shrlock().
964  */
965 
966 void
967 smb_node_start_crit(smb_node_t *node, krw_t mode)
968 {
969 	rw_enter(&node->n_lock, mode);
970 	nbl_start_crit(node->vp, mode);
971 }
972 
973 /*
974  * smb_node_end_crit()
975  *
976  * Exit critical region for share reservations.
977  */
978 
979 void
980 smb_node_end_crit(smb_node_t *node)
981 {
982 	nbl_end_crit(node->vp);
983 	rw_exit(&node->n_lock);
984 }
985 
986 int
987 smb_node_in_crit(smb_node_t *node)
988 {
989 	return (nbl_in_crit(node->vp) && RW_LOCK_HELD(&node->n_lock));
990 }
991 
992 void
993 smb_node_rdlock(smb_node_t *node)
994 {
995 	rw_enter(&node->n_lock, RW_READER);
996 }
997 
998 void
999 smb_node_wrlock(smb_node_t *node)
1000 {
1001 	rw_enter(&node->n_lock, RW_WRITER);
1002 }
1003 
1004 void
1005 smb_node_unlock(smb_node_t *node)
1006 {
1007 	rw_exit(&node->n_lock);
1008 }
1009 
1010 uint32_t
1011 smb_node_get_ofile_count(smb_node_t *node)
1012 {
1013 	uint32_t	cntr;
1014 
1015 	SMB_NODE_VALID(node);
1016 
1017 	smb_llist_enter(&node->n_ofile_list, RW_READER);
1018 	cntr = smb_llist_get_count(&node->n_ofile_list);
1019 	smb_llist_exit(&node->n_ofile_list);
1020 	return (cntr);
1021 }
1022 
1023 void
1024 smb_node_add_ofile(smb_node_t *node, smb_ofile_t *of)
1025 {
1026 	SMB_NODE_VALID(node);
1027 
1028 	smb_llist_enter(&node->n_ofile_list, RW_WRITER);
1029 	smb_llist_insert_tail(&node->n_ofile_list, of);
1030 	smb_llist_exit(&node->n_ofile_list);
1031 }
1032 
1033 void
1034 smb_node_rem_ofile(smb_node_t *node, smb_ofile_t *of)
1035 {
1036 	SMB_NODE_VALID(node);
1037 
1038 	smb_llist_enter(&node->n_ofile_list, RW_WRITER);
1039 	smb_llist_remove(&node->n_ofile_list, of);
1040 	smb_llist_exit(&node->n_ofile_list);
1041 }
1042 
1043 void
1044 smb_node_inc_open_ofiles(smb_node_t *node)
1045 {
1046 	SMB_NODE_VALID(node);
1047 
1048 	mutex_enter(&node->n_mutex);
1049 	node->n_open_count++;
1050 	mutex_exit(&node->n_mutex);
1051 }
1052 
1053 void
1054 smb_node_dec_open_ofiles(smb_node_t *node)
1055 {
1056 	SMB_NODE_VALID(node);
1057 
1058 	mutex_enter(&node->n_mutex);
1059 	node->n_open_count--;
1060 	mutex_exit(&node->n_mutex);
1061 }
1062 
1063 uint32_t
1064 smb_node_get_open_ofiles(smb_node_t *node)
1065 {
1066 	uint32_t	cnt;
1067 
1068 	SMB_NODE_VALID(node);
1069 
1070 	mutex_enter(&node->n_mutex);
1071 	cnt = node->n_open_count;
1072 	mutex_exit(&node->n_mutex);
1073 	return (cnt);
1074 }
1075 
1076 /*
1077  * smb_node_alloc
1078  */
1079 static smb_node_t *
1080 smb_node_alloc(
1081     char	*od_name,
1082     vnode_t	*vp,
1083     smb_attr_t	*attr,
1084     smb_llist_t	*bucket,
1085     uint32_t	hashkey)
1086 {
1087 	smb_node_t	*node;
1088 
1089 	node = kmem_cache_alloc(smb_node_cache, KM_SLEEP);
1090 
1091 	if (node->n_audit_buf != NULL)
1092 		node->n_audit_buf->anb_index = 0;
1093 
1094 	node->attr = *attr;
1095 	node->flags = NODE_FLAGS_ATTR_VALID;
1096 	node->n_size = node->attr.sa_vattr.va_size;
1097 	VN_HOLD(vp);
1098 	node->vp = vp;
1099 	node->n_refcnt = 1;
1100 	node->n_hash_bucket = bucket;
1101 	node->n_hashkey = hashkey;
1102 	node->n_orig_uid = 0;
1103 	node->readonly_creator = NULL;
1104 	node->waiting_event = 0;
1105 	node->what = 0;
1106 	node->n_open_count = 0;
1107 	node->dir_snode = NULL;
1108 	node->unnamed_stream_node = NULL;
1109 	node->delete_on_close_cred = NULL;
1110 
1111 	(void) strlcpy(node->od_name, od_name, sizeof (node->od_name));
1112 	if (strcmp(od_name, XATTR_DIR) == 0)
1113 		node->flags |= NODE_XATTR_DIR;
1114 
1115 	node->n_state = SMB_NODE_STATE_AVAILABLE;
1116 	node->n_magic = SMB_NODE_MAGIC;
1117 	return (node);
1118 }
1119 
1120 /*
1121  * smb_node_free
1122  */
1123 static void
1124 smb_node_free(smb_node_t *node)
1125 {
1126 	SMB_NODE_VALID(node);
1127 
1128 	node->n_magic = 0;
1129 	VERIFY(!list_link_active(&node->n_lnd));
1130 	VERIFY(node->n_lock_list.ll_count == 0);
1131 	VERIFY(node->n_ofile_list.ll_count == 0);
1132 	VERIFY(node->n_oplock.ol_xthread == NULL);
1133 	VERIFY(mutex_owner(&node->n_mutex) == NULL);
1134 	VERIFY(!RW_LOCK_HELD(&node->n_lock));
1135 	VN_RELE(node->vp);
1136 	kmem_cache_free(smb_node_cache, node);
1137 }
1138 
1139 /*
1140  * smb_node_constructor
1141  */
1142 static int
1143 smb_node_constructor(void *buf, void *un, int kmflags)
1144 {
1145 	_NOTE(ARGUNUSED(kmflags, un))
1146 
1147 	smb_node_t	*node = (smb_node_t *)buf;
1148 
1149 	bzero(node, sizeof (smb_node_t));
1150 
1151 	smb_llist_constructor(&node->n_ofile_list, sizeof (smb_ofile_t),
1152 	    offsetof(smb_ofile_t, f_nnd));
1153 	smb_llist_constructor(&node->n_lock_list, sizeof (smb_lock_t),
1154 	    offsetof(smb_lock_t, l_lnd));
1155 	cv_init(&node->n_oplock.ol_cv, NULL, CV_DEFAULT, NULL);
1156 	rw_init(&node->n_lock, NULL, RW_DEFAULT, NULL);
1157 	mutex_init(&node->n_mutex, NULL, MUTEX_DEFAULT, NULL);
1158 	smb_node_create_audit_buf(node, kmflags);
1159 	return (0);
1160 }
1161 
1162 /*
1163  * smb_node_destructor
1164  */
1165 static void
1166 smb_node_destructor(void *buf, void *un)
1167 {
1168 	_NOTE(ARGUNUSED(un))
1169 
1170 	smb_node_t	*node = (smb_node_t *)buf;
1171 
1172 	smb_node_destroy_audit_buf(node);
1173 	mutex_destroy(&node->n_mutex);
1174 	rw_destroy(&node->n_lock);
1175 	cv_destroy(&node->n_oplock.ol_cv);
1176 	smb_llist_destructor(&node->n_lock_list);
1177 	smb_llist_destructor(&node->n_ofile_list);
1178 }
1179 
1180 /*
1181  * smb_node_create_audit_buf
1182  */
1183 static void
1184 smb_node_create_audit_buf(smb_node_t *node, int kmflags)
1185 {
1186 	smb_audit_buf_node_t	*abn;
1187 
1188 	if (smb_audit_flags & SMB_AUDIT_NODE) {
1189 		abn = kmem_zalloc(sizeof (smb_audit_buf_node_t), kmflags);
1190 		abn->anb_max_index = SMB_AUDIT_BUF_MAX_REC - 1;
1191 		node->n_audit_buf = abn;
1192 	}
1193 }
1194 
1195 /*
1196  * smb_node_destroy_audit_buf
1197  */
1198 static void
1199 smb_node_destroy_audit_buf(smb_node_t *node)
1200 {
1201 	if (node->n_audit_buf != NULL) {
1202 		kmem_free(node->n_audit_buf, sizeof (smb_audit_buf_node_t));
1203 		node->n_audit_buf = NULL;
1204 	}
1205 }
1206 
1207 /*
1208  * smb_node_audit
1209  *
1210  * This function saves the calling stack in the audit buffer of the node passed
1211  * in.
1212  */
1213 static void
1214 smb_node_audit(smb_node_t *node)
1215 {
1216 	smb_audit_buf_node_t	*abn;
1217 	smb_audit_record_node_t	*anr;
1218 
1219 	if (node->n_audit_buf) {
1220 		abn = node->n_audit_buf;
1221 		anr = abn->anb_records;
1222 		anr += abn->anb_index;
1223 		abn->anb_index++;
1224 		abn->anb_index &= abn->anb_max_index;
1225 		anr->anr_refcnt = node->n_refcnt;
1226 		anr->anr_depth = getpcstack(anr->anr_stack,
1227 		    SMB_AUDIT_STACK_DEPTH);
1228 	}
1229 }
1230 
1231 static smb_llist_t *
1232 smb_node_get_hash(fsid_t *fsid, smb_attr_t *attr, uint32_t *phashkey)
1233 {
1234 	uint32_t	hashkey;
1235 
1236 	hashkey = fsid->val[0] + attr->sa_vattr.va_nodeid;
1237 	hashkey += (hashkey >> 24) + (hashkey >> 16) + (hashkey >> 8);
1238 	*phashkey = hashkey;
1239 	return (&smb_node_hash_table[(hashkey & SMBND_HASH_MASK)]);
1240 }
1241