xref: /titanic_52/usr/src/lib/libshare/common/libshare_zfs.c (revision 24fe0b3bf671e123467ce1df0b67cadd3614c8e4)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <stdio.h>
28 #include <libzfs.h>
29 #include <string.h>
30 #include <strings.h>
31 #include <libshare.h>
32 #include "libshare_impl.h"
33 #include <libintl.h>
34 #include <sys/mnttab.h>
35 #include <sys/mntent.h>
36 
37 extern sa_share_t _sa_add_share(sa_group_t, char *, int, int *, uint64_t);
38 extern sa_group_t _sa_create_zfs_group(sa_group_t, char *);
39 extern char *sa_fstype(char *);
40 extern void set_node_attr(void *, char *, char *);
41 extern int sa_is_share(void *);
42 extern void sa_update_sharetab_ts(sa_handle_t);
43 
44 /*
45  * File system specific code for ZFS. The original code was stolen
46  * from the "zfs" command and modified to better suit this library's
47  * usage.
48  */
49 
50 typedef struct get_all_cbdata {
51 	zfs_handle_t	**cb_handles;
52 	size_t		cb_alloc;
53 	size_t		cb_used;
54 	uint_t		cb_types;
55 } get_all_cbdata_t;
56 
57 /*
58  * sa_zfs_init(impl_handle)
59  *
60  * Initialize an access handle into libzfs.  The handle needs to stay
61  * around until sa_zfs_fini() in order to maintain the cache of
62  * mounts.
63  */
64 
65 int
66 sa_zfs_init(sa_handle_impl_t impl_handle)
67 {
68 	impl_handle->zfs_libhandle = libzfs_init();
69 	if (impl_handle->zfs_libhandle != NULL) {
70 		libzfs_print_on_error(impl_handle->zfs_libhandle, B_TRUE);
71 		return (B_TRUE);
72 	}
73 	return (B_FALSE);
74 }
75 
76 /*
77  * sa_zfs_fini(impl_handle)
78  *
79  * cleanup data structures and the libzfs handle used for accessing
80  * zfs file share info.
81  */
82 
83 void
84 sa_zfs_fini(sa_handle_impl_t impl_handle)
85 {
86 	if (impl_handle->zfs_libhandle != NULL) {
87 		if (impl_handle->zfs_list != NULL) {
88 			zfs_handle_t **zhp = impl_handle->zfs_list;
89 			size_t i;
90 
91 			/*
92 			 * Contents of zfs_list need to be freed so we
93 			 * don't lose ZFS handles.
94 			 */
95 			for (i = 0; i < impl_handle->zfs_list_count; i++) {
96 				zfs_close(zhp[i]);
97 			}
98 			free(impl_handle->zfs_list);
99 			impl_handle->zfs_list = NULL;
100 			impl_handle->zfs_list_count = 0;
101 		}
102 
103 		libzfs_fini(impl_handle->zfs_libhandle);
104 		impl_handle->zfs_libhandle = NULL;
105 	}
106 }
107 
108 /*
109  * get_one_filesystem(zfs_handle_t, data)
110  *
111  * an iterator function called while iterating through the ZFS
112  * root. It accumulates into an array of file system handles that can
113  * be used to derive info about those file systems.
114  *
115  * Note that as this function is called, we close all zhp handles that
116  * are not going to be places into the cp_handles list. We don't want
117  * to close the ones we are keeping, but all others would be leaked if
118  * not closed here.
119  */
120 
121 static int
122 get_one_filesystem(zfs_handle_t *zhp, void *data)
123 {
124 	get_all_cbdata_t *cbp = data;
125 	zfs_type_t type = zfs_get_type(zhp);
126 
127 	/*
128 	 * Interate over any nested datasets.
129 	 */
130 	if (type == ZFS_TYPE_FILESYSTEM &&
131 	    zfs_iter_filesystems(zhp, get_one_filesystem, data) != 0) {
132 		zfs_close(zhp);
133 		return (1);
134 	}
135 
136 	/*
137 	 * Skip any datasets whose type does not match.
138 	 */
139 	if ((type & cbp->cb_types) == 0) {
140 		zfs_close(zhp);
141 		return (0);
142 	}
143 
144 	if (cbp->cb_alloc == cbp->cb_used) {
145 		zfs_handle_t **handles;
146 
147 		if (cbp->cb_alloc == 0)
148 			cbp->cb_alloc = 64;
149 		else
150 			cbp->cb_alloc *= 2;
151 
152 		handles = (zfs_handle_t **)calloc(1,
153 		    cbp->cb_alloc * sizeof (void *));
154 
155 		if (handles == NULL) {
156 			zfs_close(zhp);
157 			return (0);
158 		}
159 		if (cbp->cb_handles) {
160 			bcopy(cbp->cb_handles, handles,
161 			    cbp->cb_used * sizeof (void *));
162 			free(cbp->cb_handles);
163 		}
164 
165 		cbp->cb_handles = handles;
166 	}
167 
168 	cbp->cb_handles[cbp->cb_used++] = zhp;
169 
170 	return (0);
171 }
172 
173 /*
174  * get_all_filesystems(zfs_handle_t ***fslist, size_t *count)
175  *
176  * iterate through all ZFS file systems starting at the root. Returns
177  * a count and an array of handle pointers. Allocating is only done
178  * once. The caller does not need to free since it will be done at
179  * sa_zfs_fini() time.
180  */
181 
182 static void
183 get_all_filesystems(sa_handle_impl_t impl_handle,
184 			zfs_handle_t ***fslist, size_t *count)
185 {
186 	get_all_cbdata_t cb = { 0 };
187 	cb.cb_types = ZFS_TYPE_FILESYSTEM;
188 
189 	if (impl_handle->zfs_list != NULL) {
190 		*fslist = impl_handle->zfs_list;
191 		*count = impl_handle->zfs_list_count;
192 		return;
193 	}
194 
195 	(void) zfs_iter_root(impl_handle->zfs_libhandle,
196 	    get_one_filesystem, &cb);
197 
198 	impl_handle->zfs_list = *fslist = cb.cb_handles;
199 	impl_handle->zfs_list_count = *count = cb.cb_used;
200 }
201 
202 /*
203  * mountpoint_compare(a, b)
204  *
205  * compares the mountpoint on two zfs file systems handles.
206  * returns values following strcmp() model.
207  */
208 
209 static int
210 mountpoint_compare(const void *a, const void *b)
211 {
212 	zfs_handle_t **za = (zfs_handle_t **)a;
213 	zfs_handle_t **zb = (zfs_handle_t **)b;
214 	char mounta[MAXPATHLEN];
215 	char mountb[MAXPATHLEN];
216 
217 	verify(zfs_prop_get(*za, ZFS_PROP_MOUNTPOINT, mounta,
218 	    sizeof (mounta), NULL, NULL, 0, B_FALSE) == 0);
219 	verify(zfs_prop_get(*zb, ZFS_PROP_MOUNTPOINT, mountb,
220 	    sizeof (mountb), NULL, NULL, 0, B_FALSE) == 0);
221 
222 	return (strcmp(mounta, mountb));
223 }
224 
225 /*
226  * return legacy mountpoint.  Caller provides space for mountpoint and
227  * dataset.
228  */
229 int
230 get_legacy_mountpoint(char *path, char *dataset, size_t dlen,
231     char *mountpoint, size_t mlen)
232 {
233 	FILE *fp;
234 	struct mnttab entry;
235 
236 	if ((fp = fopen(MNTTAB, "r")) == NULL) {
237 		return (1);
238 	}
239 
240 	while (getmntent(fp, &entry) == 0) {
241 
242 		if (entry.mnt_fstype == NULL ||
243 		    strcmp(entry.mnt_fstype, MNTTYPE_ZFS) != 0)
244 			continue;
245 
246 		if (strcmp(entry.mnt_mountp, path) == 0) {
247 			if (mlen > 0)
248 				(void) strlcpy(mountpoint, entry.mnt_mountp,
249 				    mlen);
250 			if (dlen > 0)
251 				(void) strlcpy(dataset, entry.mnt_special,
252 				    dlen);
253 			break;
254 		}
255 	}
256 	(void) fclose(fp);
257 	return (1);
258 }
259 
260 /*
261  * get_zfs_dataset(impl_handle, path)
262  *
263  * get the name of the ZFS dataset the path is equivalent to.  The
264  * dataset name is used for get/set of ZFS properties since libzfs
265  * requires a dataset to do a zfs_open().
266  */
267 
268 static char *
269 get_zfs_dataset(sa_handle_impl_t impl_handle, char *path,
270     boolean_t search_mnttab)
271 {
272 	size_t i, count = 0;
273 	char *dataset = NULL;
274 	zfs_handle_t **zlist;
275 	char mountpoint[ZFS_MAXPROPLEN];
276 	char canmount[ZFS_MAXPROPLEN];
277 
278 	get_all_filesystems(impl_handle, &zlist, &count);
279 	qsort(zlist, count, sizeof (void *), mountpoint_compare);
280 	for (i = 0; i < count; i++) {
281 		/* must have a mountpoint */
282 		if (zfs_prop_get(zlist[i], ZFS_PROP_MOUNTPOINT, mountpoint,
283 		    sizeof (mountpoint), NULL, NULL, 0, B_FALSE) != 0) {
284 			/* no mountpoint */
285 			continue;
286 		}
287 
288 		/* mountpoint must be a path */
289 		if (strcmp(mountpoint, ZFS_MOUNTPOINT_NONE) == 0 ||
290 		    strcmp(mountpoint, ZFS_MOUNTPOINT_LEGACY) == 0) {
291 			/*
292 			 * Search mmttab for mountpoint and get dataset.
293 			 */
294 
295 			if (search_mnttab == B_TRUE &&
296 			    get_legacy_mountpoint(path, mountpoint,
297 			    sizeof (mountpoint), NULL, 0) == 0) {
298 				dataset = mountpoint;
299 				break;
300 			}
301 			continue;
302 		}
303 
304 		/* canmount must be set */
305 		canmount[0] = '\0';
306 		if (zfs_prop_get(zlist[i], ZFS_PROP_CANMOUNT, canmount,
307 		    sizeof (canmount), NULL, NULL, 0, B_FALSE) != 0 ||
308 		    strcmp(canmount, "off") == 0)
309 			continue;
310 
311 		/*
312 		 * have a mountable handle but want to skip those marked none
313 		 * and legacy
314 		 */
315 		if (strcmp(mountpoint, path) == 0) {
316 			dataset = (char *)zfs_get_name(zlist[i]);
317 			break;
318 		}
319 
320 	}
321 
322 	if (dataset != NULL)
323 		dataset = strdup(dataset);
324 
325 	return (dataset);
326 }
327 
328 /*
329  * get_zfs_property(dataset, property)
330  *
331  * Get the file system property specified from the ZFS dataset.
332  */
333 
334 static char *
335 get_zfs_property(char *dataset, zfs_prop_t property)
336 {
337 	zfs_handle_t *handle = NULL;
338 	char shareopts[ZFS_MAXPROPLEN];
339 	libzfs_handle_t *libhandle;
340 
341 	libhandle = libzfs_init();
342 	if (libhandle != NULL) {
343 		handle = zfs_open(libhandle, dataset, ZFS_TYPE_FILESYSTEM);
344 		if (handle != NULL) {
345 			if (zfs_prop_get(handle, property, shareopts,
346 			    sizeof (shareopts), NULL, NULL, 0,
347 			    B_FALSE) == 0) {
348 				zfs_close(handle);
349 				libzfs_fini(libhandle);
350 				return (strdup(shareopts));
351 			}
352 			zfs_close(handle);
353 		}
354 		libzfs_fini(libhandle);
355 	}
356 	return (NULL);
357 }
358 
359 /*
360  * sa_zfs_is_shared(handle, path)
361  *
362  * Check to see if the ZFS path provided has the sharenfs option set
363  * or not.
364  */
365 
366 int
367 sa_zfs_is_shared(sa_handle_t sahandle, char *path)
368 {
369 	int ret = 0;
370 	char *dataset;
371 	zfs_handle_t *handle = NULL;
372 	char shareopts[ZFS_MAXPROPLEN];
373 	libzfs_handle_t *libhandle;
374 
375 	dataset = get_zfs_dataset((sa_handle_t)sahandle, path, B_FALSE);
376 	if (dataset != NULL) {
377 		libhandle = libzfs_init();
378 		if (libhandle != NULL) {
379 			handle = zfs_open(libhandle, dataset,
380 			    ZFS_TYPE_FILESYSTEM);
381 			if (handle != NULL) {
382 				if (zfs_prop_get(handle, ZFS_PROP_SHARENFS,
383 				    shareopts, sizeof (shareopts), NULL, NULL,
384 				    0, B_FALSE) == 0 &&
385 				    strcmp(shareopts, "off") != 0) {
386 					ret = 1; /* it is shared */
387 				}
388 				zfs_close(handle);
389 			}
390 			libzfs_fini(libhandle);
391 		}
392 		free(dataset);
393 	}
394 	return (ret);
395 }
396 
397 /*
398  * find_or_create_group(handle, groupname, proto, *err)
399  *
400  * While walking the ZFS tree, we need to add shares to a defined
401  * group. If the group doesn't exist, create it first, making sure it
402  * is marked as a ZFS group.
403  *
404  * Note that all ZFS shares are in a subgroup of the top level group
405  * called "zfs".
406  */
407 
408 static sa_group_t
409 find_or_create_group(sa_handle_t handle, char *groupname, char *proto, int *err)
410 {
411 	sa_group_t group;
412 	sa_optionset_t optionset;
413 	int ret = SA_OK;
414 
415 	/*
416 	 * we check to see if the "zfs" group exists. Since this
417 	 * should be the top level group, we don't want the
418 	 * parent. This is to make sure the zfs group has been created
419 	 * and to created if it hasn't been.
420 	 */
421 	group = sa_get_group(handle, groupname);
422 	if (group == NULL) {
423 		group = sa_create_group(handle, groupname, &ret);
424 
425 		/* make sure this is flagged as a ZFS group */
426 		if (group != NULL)
427 			ret = sa_set_group_attr(group, "zfs", "true");
428 	}
429 	if (group != NULL) {
430 		if (proto != NULL) {
431 			optionset = sa_get_optionset(group, proto);
432 			if (optionset == NULL)
433 				optionset = sa_create_optionset(group, proto);
434 		}
435 	}
436 	if (err != NULL)
437 		*err = ret;
438 	return (group);
439 }
440 
441 /*
442  * find_or_create_zfs_subgroup(groupname, optstring, *err)
443  *
444  * ZFS shares will be in a subgroup of the "zfs" master group.  This
445  * function looks to see if the groupname exists and returns it if it
446  * does or else creates a new one with the specified name and returns
447  * that.  The "zfs" group will exist before we get here, but we make
448  * sure just in case.
449  *
450  * err must be a valid pointer.
451  */
452 
453 static sa_group_t
454 find_or_create_zfs_subgroup(sa_handle_t handle, char *groupname, char *proto,
455     char *optstring, int *err)
456 {
457 	sa_group_t group = NULL;
458 	sa_group_t zfs;
459 	char *name;
460 	char *options;
461 
462 	/* start with the top-level "zfs" group */
463 	zfs = sa_get_group(handle, "zfs");
464 	*err = SA_OK;
465 	if (zfs != NULL) {
466 		for (group = sa_get_sub_group(zfs); group != NULL;
467 		    group = sa_get_next_group(group)) {
468 			name = sa_get_group_attr(group, "name");
469 			if (name != NULL && strcmp(name, groupname) == 0) {
470 				/* have the group so break out of here */
471 				sa_free_attr_string(name);
472 				break;
473 			}
474 			if (name != NULL)
475 				sa_free_attr_string(name);
476 		}
477 
478 		if (group == NULL) {
479 			/*
480 			 * Need to create the sub-group since it doesn't exist
481 			 */
482 			group = _sa_create_zfs_group(zfs, groupname);
483 			if (group == NULL) {
484 				*err = SA_NO_MEMORY;
485 				return (NULL);
486 			}
487 			set_node_attr(group, "zfs", "true");
488 		}
489 		if (strcmp(optstring, "on") == 0)
490 			optstring = "rw";
491 		options = strdup(optstring);
492 		if (options != NULL) {
493 			*err = sa_parse_legacy_options(group, options,
494 			    proto);
495 			/* If no optionset, add one. */
496 			if (sa_get_optionset(group, proto) == NULL)
497 				(void) sa_create_optionset(group, proto);
498 			free(options);
499 		} else {
500 			*err = SA_NO_MEMORY;
501 		}
502 	}
503 	return (group);
504 }
505 
506 /*
507  * zfs_construct_resource(share, name, base, dataset)
508  *
509  * Add a resource to the share using name as a template. If name ==
510  * NULL, then construct a name based on the dataset value.
511  * name.
512  */
513 static void
514 zfs_construct_resource(sa_share_t share, char *dataset)
515 {
516 	char buff[SA_MAX_RESOURCE_NAME + 1];
517 	int ret = SA_OK;
518 
519 	(void) snprintf(buff, SA_MAX_RESOURCE_NAME, "%s", dataset);
520 	sa_fix_resource_name(buff);
521 	(void) sa_add_resource(share, buff, SA_SHARE_TRANSIENT, &ret);
522 }
523 
524 /*
525  * zfs_inherited(handle, source, sourcestr)
526  *
527  * handle case of inherited share{nfs,smb}. Pulled out of sa_get_zfs_shares
528  * for readability.
529  */
530 static int
531 zfs_inherited(sa_handle_t handle, sa_share_t share, char *sourcestr,
532     char *shareopts, char *mountpoint, char *proto, char *dataset)
533 {
534 	int doshopt = 0;
535 	int err = SA_OK;
536 	sa_group_t group;
537 	sa_resource_t resource;
538 	uint64_t features;
539 
540 	/*
541 	 * Need to find the "real" parent sub-group. It may not be
542 	 * mounted, but it was identified in the "sourcestr"
543 	 * variable. The real parent not mounted can occur if
544 	 * "canmount=off and sharenfs=on".
545 	 */
546 	group = find_or_create_zfs_subgroup(handle, sourcestr, proto,
547 	    shareopts, &doshopt);
548 	if (group != NULL) {
549 		/*
550 		 * We may need the first share for resource
551 		 * prototype. We only care about it if it has a
552 		 * resource that sets a prefix value.
553 		 */
554 		if (share == NULL)
555 			share = _sa_add_share(group, mountpoint,
556 			    SA_SHARE_TRANSIENT, &err,
557 			    (uint64_t)SA_FEATURE_NONE);
558 		/*
559 		 * some options may only be on shares. If the opt
560 		 * string contains one of those, we put it just on the
561 		 * share.
562 		 */
563 		if (share != NULL && doshopt == SA_PROP_SHARE_ONLY) {
564 			char *options;
565 			options = strdup(shareopts);
566 			if (options != NULL) {
567 				set_node_attr(share, "dataset", dataset);
568 				err = sa_parse_legacy_options(share, options,
569 				    proto);
570 				set_node_attr(share, "dataset", NULL);
571 				free(options);
572 			}
573 			if (sa_get_optionset(group, proto) == NULL)
574 				(void) sa_create_optionset(group, proto);
575 		}
576 		features = sa_proto_get_featureset(proto);
577 		if (share != NULL && features & SA_FEATURE_RESOURCE) {
578 			/*
579 			 * We have a share and the protocol requires
580 			 * that at least one resource exist (probably
581 			 * SMB). We need to make sure that there is at
582 			 * least one.
583 			 */
584 			resource = sa_get_share_resource(share, NULL);
585 			if (resource == NULL) {
586 				zfs_construct_resource(share, dataset);
587 			}
588 		}
589 	} else {
590 		err = SA_NO_MEMORY;
591 	}
592 	return (err);
593 }
594 
595 /*
596  * zfs_notinherited(group, share, mountpoint, shareopts, proto, dataset,
597  *     grouperr)
598  *
599  * handle case where this is the top of a sub-group in ZFS. Pulled out
600  * of sa_get_zfs_shares for readability. We need the grouperr from the
601  * creation of the subgroup to know whether to add the public
602  * property, etc. to the specific share.
603  */
604 static int
605 zfs_notinherited(sa_group_t group, sa_share_t share, char *mountpoint,
606     char *shareopts, char *proto, char *dataset, int grouperr)
607 {
608 	int err = SA_OK;
609 	sa_resource_t resource;
610 	uint64_t features;
611 
612 	set_node_attr(group, "zfs", "true");
613 	if (share == NULL)
614 		share = _sa_add_share(group, mountpoint, SA_SHARE_TRANSIENT,
615 		    &err, (uint64_t)SA_FEATURE_NONE);
616 
617 	if (err != SA_OK)
618 		return (err);
619 
620 	if (strcmp(shareopts, "on") == 0)
621 		shareopts = "";
622 	if (shareopts != NULL) {
623 		char *options;
624 		if (grouperr == SA_PROP_SHARE_ONLY) {
625 			/*
626 			 * Some properties may only be on shares, but
627 			 * due to the ZFS sub-groups being artificial,
628 			 * we sometimes get this and have to deal with
629 			 * it. We do it by attempting to put it on the
630 			 * share.
631 			 */
632 			options = strdup(shareopts);
633 			if (options != NULL) {
634 				err = sa_parse_legacy_options(share,
635 				    options, proto);
636 				free(options);
637 			}
638 		}
639 		/* Unmark the share's changed state */
640 		set_node_attr(share, "changed", NULL);
641 	}
642 	features = sa_proto_get_featureset(proto);
643 	if (share != NULL && features & SA_FEATURE_RESOURCE) {
644 		/*
645 		 * We have a share and the protocol requires that at
646 		 * least one resource exist (probably SMB). We need to
647 		 * make sure that there is at least one.
648 		 */
649 		resource = sa_get_share_resource(share, NULL);
650 		if (resource == NULL) {
651 			zfs_construct_resource(share, dataset);
652 		}
653 	}
654 	return (err);
655 }
656 
657 /*
658  * zfs_grp_error(err)
659  *
660  * Print group create error, but only once. If err is 0 do the
661  * print else don't.
662  */
663 
664 static void
665 zfs_grp_error(int err)
666 {
667 	if (err == 0) {
668 		/* only print error once */
669 		(void) fprintf(stderr, dgettext(TEXT_DOMAIN,
670 		    "Cannot create ZFS subgroup during initialization:"
671 		    " %s\n"), sa_errorstr(SA_SYSTEM_ERR));
672 	}
673 }
674 
675 /*
676  * zfs_process_share(handle, share, mountpoint, proto, source,
677  *     shareopts, sourcestr)
678  *
679  * Creates the subgroup, if necessary and adds shares, resources
680  * and properties.
681  */
682 int
683 sa_zfs_process_share(sa_handle_t handle, sa_group_t group, sa_share_t share,
684     char *mountpoint, char *proto, zprop_source_t source, char *shareopts,
685     char *sourcestr, char *dataset)
686 {
687 	int err = SA_OK;
688 
689 	if (source & ZPROP_SRC_INHERITED) {
690 		err = zfs_inherited(handle, share, sourcestr, shareopts,
691 		    mountpoint, proto, dataset);
692 	} else {
693 		group = find_or_create_zfs_subgroup(handle, dataset, proto,
694 		    shareopts, &err);
695 		if (group == NULL) {
696 			static boolean_t reported_error = B_FALSE;
697 			/*
698 			 * There is a problem, but we can't do
699 			 * anything about it at this point so we issue
700 			 * a warning and move on.
701 			 */
702 			zfs_grp_error(reported_error);
703 			reported_error = B_TRUE;
704 		}
705 		set_node_attr(group, "zfs", "true");
706 		/*
707 		 * Add share with local opts via zfs_notinherited.
708 		 */
709 		err = zfs_notinherited(group, share, mountpoint, shareopts,
710 		    proto, dataset, err);
711 	}
712 	return (err);
713 }
714 
715 /*
716  * sa_get_zfs_shares(handle, groupname)
717  *
718  * Walk the mnttab for all zfs mounts and determine which are
719  * shared. Find or create the appropriate group/sub-group to contain
720  * the shares.
721  *
722  * All shares are in a sub-group that will hold the properties. This
723  * allows representing the inherited property model.
724  *
725  * One area of complication is if "sharenfs" is set at one level of
726  * the directory tree and "sharesmb" is set at a different level, the
727  * a sub-group must be formed at the lower level for both
728  * protocols. That is the nature of the problem in CR 6667349.
729  */
730 
731 int
732 sa_get_zfs_shares(sa_handle_t handle, char *groupname)
733 {
734 	sa_group_t zfsgroup;
735 	boolean_t nfs;
736 	boolean_t nfs_inherited;
737 	boolean_t smb;
738 	boolean_t smb_inherited;
739 	zfs_handle_t **zlist;
740 	char nfsshareopts[ZFS_MAXPROPLEN];
741 	char smbshareopts[ZFS_MAXPROPLEN];
742 	sa_share_t share;
743 	zprop_source_t source;
744 	char nfssourcestr[ZFS_MAXPROPLEN];
745 	char smbsourcestr[ZFS_MAXPROPLEN];
746 	char mountpoint[ZFS_MAXPROPLEN];
747 	size_t count = 0, i;
748 	libzfs_handle_t *zfs_libhandle;
749 	int err = SA_OK;
750 
751 	/*
752 	 * If we can't access libzfs, don't bother doing anything.
753 	 */
754 	zfs_libhandle = ((sa_handle_impl_t)handle)->zfs_libhandle;
755 	if (zfs_libhandle == NULL)
756 		return (SA_SYSTEM_ERR);
757 
758 	zfsgroup = find_or_create_group(handle, groupname, NULL, &err);
759 	/* Not an error, this could be a legacy condition */
760 	if (zfsgroup == NULL)
761 		return (SA_OK);
762 
763 	/*
764 	 * need to walk the mounted ZFS pools and datasets to
765 	 * find shares that are possible.
766 	 */
767 	get_all_filesystems((sa_handle_impl_t)handle, &zlist, &count);
768 	qsort(zlist, count, sizeof (void *), mountpoint_compare);
769 
770 	for (i = 0; i < count; i++) {
771 		char *dataset;
772 
773 		source = ZPROP_SRC_ALL;
774 		/* If no mountpoint, skip. */
775 		if (zfs_prop_get(zlist[i], ZFS_PROP_MOUNTPOINT,
776 		    mountpoint, sizeof (mountpoint), NULL, NULL, 0,
777 		    B_FALSE) != 0)
778 			continue;
779 
780 		/*
781 		 * zfs_get_name value must not be freed. It is just a
782 		 * pointer to a value in the handle.
783 		 */
784 		if ((dataset = (char *)zfs_get_name(zlist[i])) == NULL)
785 			continue;
786 
787 		/*
788 		 * only deal with "mounted" file systems since
789 		 * unmounted file systems can't actually be shared.
790 		 */
791 
792 		if (!zfs_is_mounted(zlist[i], NULL))
793 			continue;
794 
795 		nfs = nfs_inherited = B_FALSE;
796 
797 		if (zfs_prop_get(zlist[i], ZFS_PROP_SHARENFS, nfsshareopts,
798 		    sizeof (nfsshareopts), &source, nfssourcestr,
799 		    ZFS_MAXPROPLEN, B_FALSE) == 0 &&
800 		    strcmp(nfsshareopts, "off") != 0) {
801 			if (source & ZPROP_SRC_INHERITED)
802 				nfs_inherited = B_TRUE;
803 			else
804 				nfs = B_TRUE;
805 		}
806 
807 		smb = smb_inherited = B_FALSE;
808 		if (zfs_prop_get(zlist[i], ZFS_PROP_SHARESMB, smbshareopts,
809 		    sizeof (smbshareopts), &source, smbsourcestr,
810 		    ZFS_MAXPROPLEN, B_FALSE) == 0 &&
811 		    strcmp(smbshareopts, "off") != 0) {
812 			if (source & ZPROP_SRC_INHERITED)
813 				smb_inherited = B_TRUE;
814 			else
815 				smb = B_TRUE;
816 		}
817 
818 		/*
819 		 * If the mountpoint is already shared, it must be a
820 		 * non-ZFS share. We want to remove the share from its
821 		 * parent group and reshare it under ZFS.
822 		 */
823 		share = sa_find_share(handle, mountpoint);
824 		if (share != NULL &&
825 		    (nfs || smb || nfs_inherited || smb_inherited)) {
826 			err = sa_remove_share(share);
827 			share = NULL;
828 		}
829 
830 		/*
831 		 * At this point, we have the information needed to
832 		 * determine what to do with the share.
833 		 *
834 		 * If smb or nfs is set, we have a new sub-group.
835 		 * If smb_inherit and/or nfs_inherit is set, then
836 		 * place on an existing sub-group. If both are set,
837 		 * the existing sub-group is the closest up the tree.
838 		 */
839 		if (nfs || smb) {
840 			/*
841 			 * Non-inherited is the straightforward
842 			 * case. sa_zfs_process_share handles it
843 			 * directly. Make sure that if the "other"
844 			 * protocol is inherited, that we treat it as
845 			 * non-inherited as well.
846 			 */
847 			if (nfs || nfs_inherited) {
848 				err = sa_zfs_process_share(handle, zfsgroup,
849 				    share, mountpoint, "nfs",
850 				    0, nfsshareopts,
851 				    nfssourcestr, dataset);
852 				share = sa_find_share(handle, mountpoint);
853 			}
854 			if (smb || smb_inherited) {
855 				err = sa_zfs_process_share(handle, zfsgroup,
856 				    share, mountpoint, "smb",
857 				    0, smbshareopts,
858 				    smbsourcestr, dataset);
859 			}
860 		} else if (nfs_inherited || smb_inherited) {
861 			char *grpdataset;
862 			/*
863 			 * If we only have inherited groups, it is
864 			 * important to find the closer of the two if
865 			 * the protocols are set at different
866 			 * levels. The closest sub-group is the one we
867 			 * want to work with.
868 			 */
869 			if (nfs_inherited && smb_inherited) {
870 				if (strcmp(nfssourcestr, smbsourcestr) <= 0)
871 					grpdataset = nfssourcestr;
872 				else
873 					grpdataset = smbsourcestr;
874 			} else if (nfs_inherited) {
875 				grpdataset = nfssourcestr;
876 			} else if (smb_inherited) {
877 				grpdataset = smbsourcestr;
878 			}
879 			if (nfs_inherited) {
880 				err = sa_zfs_process_share(handle, zfsgroup,
881 				    share, mountpoint, "nfs",
882 				    ZPROP_SRC_INHERITED, nfsshareopts,
883 				    grpdataset, dataset);
884 				share = sa_find_share(handle, mountpoint);
885 			}
886 			if (smb_inherited) {
887 				err = sa_zfs_process_share(handle, zfsgroup,
888 				    share, mountpoint, "smb",
889 				    ZPROP_SRC_INHERITED, smbshareopts,
890 				    grpdataset, dataset);
891 			}
892 		}
893 	}
894 	/*
895 	 * Don't need to free the "zlist" variable since it is only a
896 	 * pointer to a cached value that will be freed when
897 	 * sa_fini() is called.
898 	 */
899 	return (err);
900 }
901 
902 #define	COMMAND		"/usr/sbin/zfs"
903 
904 /*
905  * sa_zfs_set_sharenfs(group, path, on)
906  *
907  * Update the "sharenfs" property on the path. If on is true, then set
908  * to the properties on the group or "on" if no properties are
909  * defined. Set to "off" if on is false.
910  */
911 
912 int
913 sa_zfs_set_sharenfs(sa_group_t group, char *path, int on)
914 {
915 	int ret = SA_NOT_IMPLEMENTED;
916 	char *command;
917 
918 	command = malloc(ZFS_MAXPROPLEN * 2);
919 	if (command != NULL) {
920 		char *opts = NULL;
921 		char *dataset = NULL;
922 		FILE *pfile;
923 		sa_handle_impl_t impl_handle;
924 		/* for now, NFS is always available for "zfs" */
925 		if (on) {
926 			opts = sa_proto_legacy_format("nfs", group, 1);
927 			if (opts != NULL && strlen(opts) == 0) {
928 				free(opts);
929 				opts = strdup("on");
930 			}
931 		}
932 
933 		impl_handle = (sa_handle_impl_t)sa_find_group_handle(group);
934 		assert(impl_handle != NULL);
935 		if (impl_handle != NULL)
936 			dataset = get_zfs_dataset(impl_handle, path, B_FALSE);
937 		else
938 			ret = SA_SYSTEM_ERR;
939 
940 		if (dataset != NULL) {
941 			(void) snprintf(command, ZFS_MAXPROPLEN * 2,
942 			    "%s set sharenfs=\"%s\" %s", COMMAND,
943 			    opts != NULL ? opts : "off", dataset);
944 			pfile = popen(command, "r");
945 			if (pfile != NULL) {
946 				ret = pclose(pfile);
947 				if (ret != 0)
948 					ret = SA_SYSTEM_ERR;
949 			}
950 		}
951 		if (opts != NULL)
952 			free(opts);
953 		if (dataset != NULL)
954 			free(dataset);
955 		free(command);
956 	}
957 	return (ret);
958 }
959 
960 /*
961  * add_resources(share, opt)
962  *
963  * Add resource properties to those in "opt".  Resources are prefixed
964  * with name=resourcename.
965  */
966 static char *
967 add_resources(sa_share_t share, char *opt)
968 {
969 	char *newopt = NULL;
970 	char *propstr;
971 	sa_resource_t resource;
972 
973 	newopt = strdup(opt);
974 	if (newopt == NULL)
975 		return (newopt);
976 
977 	for (resource = sa_get_share_resource(share, NULL);
978 	    resource != NULL;
979 	    resource = sa_get_next_resource(resource)) {
980 		char *name;
981 		size_t size;
982 
983 		name = sa_get_resource_attr(resource, "name");
984 		if (name == NULL) {
985 			free(newopt);
986 			return (NULL);
987 		}
988 		size = strlen(name) + strlen(opt) + sizeof ("name=") + 1;
989 		newopt = calloc(1, size);
990 		if (newopt != NULL)
991 			(void) snprintf(newopt, size, "%s,name=%s", opt, name);
992 		free(opt);
993 		opt = newopt;
994 		propstr = sa_proto_legacy_format("smb", resource, 0);
995 		if (propstr == NULL) {
996 			free(opt);
997 			return (NULL);
998 		}
999 		size = strlen(propstr) + strlen(opt) + 2;
1000 		newopt = calloc(1, size);
1001 		if (newopt != NULL)
1002 			(void) snprintf(newopt, size, "%s,%s", opt, propstr);
1003 		free(opt);
1004 		opt = newopt;
1005 	}
1006 	return (opt);
1007 }
1008 
1009 /*
1010  * sa_zfs_set_sharesmb(group, path, on)
1011  *
1012  * Update the "sharesmb" property on the path. If on is true, then set
1013  * to the properties on the group or "on" if no properties are
1014  * defined. Set to "off" if on is false.
1015  */
1016 
1017 int
1018 sa_zfs_set_sharesmb(sa_group_t group, char *path, int on)
1019 {
1020 	int ret = SA_NOT_IMPLEMENTED;
1021 	char *command;
1022 	sa_share_t share;
1023 
1024 	/* In case SMB not enabled */
1025 	if (sa_get_optionset(group, "smb") == NULL)
1026 		return (SA_NOT_SUPPORTED);
1027 
1028 	command = malloc(ZFS_MAXPROPLEN * 2);
1029 	if (command != NULL) {
1030 		char *opts = NULL;
1031 		char *dataset = NULL;
1032 		FILE *pfile;
1033 		sa_handle_impl_t impl_handle;
1034 
1035 		if (on) {
1036 			char *newopt;
1037 
1038 			share = sa_get_share(group, NULL);
1039 			opts = sa_proto_legacy_format("smb", share, 1);
1040 			if (opts != NULL && strlen(opts) == 0) {
1041 				free(opts);
1042 				opts = strdup("on");
1043 			}
1044 			newopt = add_resources(opts, share);
1045 			free(opts);
1046 			opts = newopt;
1047 		}
1048 
1049 		impl_handle = (sa_handle_impl_t)sa_find_group_handle(group);
1050 		assert(impl_handle != NULL);
1051 		if (impl_handle != NULL)
1052 			dataset = get_zfs_dataset(impl_handle, path, B_FALSE);
1053 		else
1054 			ret = SA_SYSTEM_ERR;
1055 
1056 		if (dataset != NULL) {
1057 			(void) snprintf(command, ZFS_MAXPROPLEN * 2,
1058 			    "echo %s set sharesmb=\"%s\" %s", COMMAND,
1059 			    opts != NULL ? opts : "off", dataset);
1060 			pfile = popen(command, "r");
1061 			if (pfile != NULL) {
1062 				ret = pclose(pfile);
1063 				if (ret != 0)
1064 					ret = SA_SYSTEM_ERR;
1065 			}
1066 		}
1067 		if (opts != NULL)
1068 			free(opts);
1069 		if (dataset != NULL)
1070 			free(dataset);
1071 		free(command);
1072 	}
1073 	return (ret);
1074 }
1075 
1076 /*
1077  * sa_zfs_update(group)
1078  *
1079  * call back to ZFS to update the share if necessary.
1080  * Don't do it if it isn't a real change.
1081  */
1082 int
1083 sa_zfs_update(sa_group_t group)
1084 {
1085 	sa_optionset_t protopt;
1086 	sa_group_t parent;
1087 	char *command;
1088 	char *optstring;
1089 	int ret = SA_OK;
1090 	int doupdate = 0;
1091 	FILE *pfile;
1092 
1093 	if (sa_is_share(group))
1094 		parent = sa_get_parent_group(group);
1095 	else
1096 		parent = group;
1097 
1098 	if (parent != NULL) {
1099 		command = malloc(ZFS_MAXPROPLEN * 2);
1100 		if (command == NULL)
1101 			return (SA_NO_MEMORY);
1102 
1103 		*command = '\0';
1104 		for (protopt = sa_get_optionset(parent, NULL); protopt != NULL;
1105 		    protopt = sa_get_next_optionset(protopt)) {
1106 
1107 			char *proto = sa_get_optionset_attr(protopt, "type");
1108 			char *path;
1109 			char *dataset = NULL;
1110 			char *zfsopts = NULL;
1111 
1112 			if (sa_is_share(group)) {
1113 				path = sa_get_share_attr((sa_share_t)group,
1114 				    "path");
1115 				if (path != NULL) {
1116 					sa_handle_impl_t impl_handle;
1117 
1118 					impl_handle = sa_find_group_handle(
1119 					    group);
1120 					if (impl_handle != NULL)
1121 						dataset = get_zfs_dataset(
1122 						    impl_handle, path, B_FALSE);
1123 					else
1124 						ret = SA_SYSTEM_ERR;
1125 
1126 					sa_free_attr_string(path);
1127 				}
1128 			} else {
1129 				dataset = sa_get_group_attr(group, "name");
1130 			}
1131 			/* update only when there is an optstring found */
1132 			doupdate = 0;
1133 			if (proto != NULL && dataset != NULL) {
1134 				optstring = sa_proto_legacy_format(proto,
1135 				    group, 1);
1136 				zfsopts = get_zfs_property(dataset,
1137 				    ZFS_PROP_SHARENFS);
1138 
1139 				if (optstring != NULL && zfsopts != NULL) {
1140 					if (strcmp(optstring, zfsopts) != 0)
1141 						doupdate++;
1142 				}
1143 				if (doupdate) {
1144 					if (optstring != NULL &&
1145 					    strlen(optstring) > 0) {
1146 						(void) snprintf(command,
1147 						    ZFS_MAXPROPLEN * 2,
1148 						    "%s set share%s=%s %s",
1149 						    COMMAND, proto,
1150 						    optstring, dataset);
1151 					} else {
1152 						(void) snprintf(command,
1153 						    ZFS_MAXPROPLEN * 2,
1154 						    "%s set share%s=on %s",
1155 						    COMMAND, proto,
1156 						    dataset);
1157 					}
1158 					pfile = popen(command, "r");
1159 					if (pfile != NULL)
1160 						ret = pclose(pfile);
1161 					switch (ret) {
1162 					default:
1163 					case 1:
1164 						ret = SA_SYSTEM_ERR;
1165 						break;
1166 					case 2:
1167 						ret = SA_SYNTAX_ERR;
1168 						break;
1169 					case 0:
1170 						break;
1171 					}
1172 				}
1173 				if (optstring != NULL)
1174 					free(optstring);
1175 				if (zfsopts != NULL)
1176 					free(zfsopts);
1177 			}
1178 			if (proto != NULL)
1179 				sa_free_attr_string(proto);
1180 			if (dataset != NULL)
1181 				free(dataset);
1182 		}
1183 		free(command);
1184 	}
1185 	return (ret);
1186 }
1187 
1188 /*
1189  * sa_group_is_zfs(group)
1190  *
1191  * Given the group, determine if the zfs attribute is set.
1192  */
1193 
1194 int
1195 sa_group_is_zfs(sa_group_t group)
1196 {
1197 	char *zfs;
1198 	int ret = 0;
1199 
1200 	zfs = sa_get_group_attr(group, "zfs");
1201 	if (zfs != NULL) {
1202 		ret = 1;
1203 		sa_free_attr_string(zfs);
1204 	}
1205 	return (ret);
1206 }
1207 
1208 /*
1209  * sa_path_is_zfs(path)
1210  *
1211  * Check to see if the file system path represents is of type "zfs".
1212  */
1213 
1214 int
1215 sa_path_is_zfs(char *path)
1216 {
1217 	char *fstype;
1218 	int ret = 0;
1219 
1220 	fstype = sa_fstype(path);
1221 	if (fstype != NULL && strcmp(fstype, "zfs") == 0)
1222 		ret = 1;
1223 	if (fstype != NULL)
1224 		sa_free_fstype(fstype);
1225 	return (ret);
1226 }
1227 
1228 int
1229 sa_sharetab_fill_zfs(sa_share_t share, share_t *sh, char *proto)
1230 {
1231 	char *path;
1232 
1233 	/* Make sure path is valid */
1234 
1235 	path = sa_get_share_attr(share, "path");
1236 	if (path != NULL) {
1237 		(void) memset(sh, 0, sizeof (sh));
1238 		(void) sa_fillshare(share, proto, sh);
1239 		sa_free_attr_string(path);
1240 		return (0);
1241 	} else
1242 		return (1);
1243 }
1244 
1245 #define	SMAX(i, j)	\
1246 	if ((j) > (i)) { \
1247 		(i) = (j); \
1248 	}
1249 
1250 int
1251 sa_share_zfs(sa_share_t share, sa_resource_t resource, char *path, share_t *sh,
1252     void *exportdata, zfs_share_op_t operation)
1253 {
1254 	libzfs_handle_t *libhandle;
1255 	sa_group_t group;
1256 	sa_handle_t sahandle;
1257 	char *dataset;
1258 	int err = EINVAL;
1259 	int i, j;
1260 	char newpath[MAXPATHLEN];
1261 	char *pathp;
1262 
1263 	/*
1264 	 * First find the dataset name
1265 	 */
1266 	if ((group = sa_get_parent_group(share)) == NULL)  {
1267 		return (SA_SYSTEM_ERR);
1268 	}
1269 	if ((sahandle = sa_find_group_handle(group)) == NULL) {
1270 		return (SA_SYSTEM_ERR);
1271 	}
1272 
1273 	/*
1274 	 * If get_zfs_dataset fails, see if it is a subdirectory
1275 	 */
1276 
1277 	pathp = path;
1278 	while ((dataset = get_zfs_dataset(sahandle, pathp, B_TRUE)) == NULL) {
1279 		char *p;
1280 
1281 		if (pathp == path) {
1282 			(void) strlcpy(newpath, path, sizeof (newpath));
1283 			pathp = newpath;
1284 		}
1285 
1286 		/*
1287 		 * Make sure only one leading '/' This condition came
1288 		 * about when using HAStoragePlus which insisted on
1289 		 * putting an extra leading '/' in the ZFS path
1290 		 * name. The problem is fixed in other areas, but this
1291 		 * will catch any other ways that a double slash might
1292 		 * get introduced.
1293 		 */
1294 		while (*pathp == '/' && *(pathp + 1) == '/')
1295 			pathp++;
1296 
1297 		/*
1298 		 * chop off part of path, but if we are at root then
1299 		 * make sure path is a /
1300 		 */
1301 		if ((strlen(pathp) > 1) && (p = strrchr(pathp, '/'))) {
1302 			if (pathp == p) {
1303 				*(p + 1) = '\0';  /* skip over /, root case */
1304 			} else {
1305 				*p = '\0';
1306 			}
1307 		} else {
1308 			return (SA_SYSTEM_ERR);
1309 		}
1310 	}
1311 
1312 	libhandle = libzfs_init();
1313 	if (libhandle != NULL) {
1314 		char *resource_name;
1315 
1316 		i = (sh->sh_path ? strlen(sh->sh_path) : 0);
1317 		sh->sh_size = i;
1318 
1319 		j = (sh->sh_res ? strlen(sh->sh_res) : 0);
1320 		sh->sh_size += j;
1321 		SMAX(i, j);
1322 
1323 		j = (sh->sh_fstype ? strlen(sh->sh_fstype) : 0);
1324 		sh->sh_size += j;
1325 		SMAX(i, j);
1326 
1327 		j = (sh->sh_opts ? strlen(sh->sh_opts) : 0);
1328 		sh->sh_size += j;
1329 		SMAX(i, j);
1330 
1331 		j = (sh->sh_descr ? strlen(sh->sh_descr) : 0);
1332 		sh->sh_size += j;
1333 		SMAX(i, j);
1334 
1335 		resource_name = sa_get_resource_attr(resource, "name");
1336 
1337 		err = zfs_deleg_share_nfs(libhandle, dataset, path,
1338 		    resource_name, exportdata, sh, i, operation);
1339 		if (err == SA_OK)
1340 			sa_update_sharetab_ts(sahandle);
1341 		if (resource_name)
1342 			sa_free_attr_string(resource_name);
1343 
1344 		libzfs_fini(libhandle);
1345 	}
1346 	free(dataset);
1347 	return (err);
1348 }
1349 
1350 /*
1351  * sa_get_zfs_handle(handle)
1352  *
1353  * Given an sa_handle_t, return the libzfs_handle_t *. This is only
1354  * used internally by libzfs. Needed in order to avoid including
1355  * libshare_impl.h in libzfs.
1356  */
1357 
1358 libzfs_handle_t *
1359 sa_get_zfs_handle(sa_handle_t handle)
1360 {
1361 	sa_handle_impl_t implhandle = (sa_handle_impl_t)handle;
1362 
1363 	return (implhandle->zfs_libhandle);
1364 }
1365 
1366 /*
1367  * sa_get_zfs_info(libzfs, path, mountpoint, dataset)
1368  *
1369  * Find the ZFS dataset and mountpoint for a given path
1370  */
1371 int
1372 sa_zfs_get_info(libzfs_handle_t *libzfs, char *path, char *mountpointp,
1373     char *datasetp)
1374 {
1375 	get_all_cbdata_t cb = { 0 };
1376 	int i;
1377 	char mountpoint[ZFS_MAXPROPLEN];
1378 	char dataset[ZFS_MAXPROPLEN];
1379 	char canmount[ZFS_MAXPROPLEN];
1380 	char *dp;
1381 	int count;
1382 	int ret = 0;
1383 
1384 	cb.cb_types = ZFS_TYPE_FILESYSTEM;
1385 
1386 	if (libzfs == NULL)
1387 		return (0);
1388 
1389 	(void) zfs_iter_root(libzfs, get_one_filesystem, &cb);
1390 	count = cb.cb_used;
1391 
1392 	qsort(cb.cb_handles, count, sizeof (void *), mountpoint_compare);
1393 	for (i = 0; i < count; i++) {
1394 		/* must have a mountpoint */
1395 		if (zfs_prop_get(cb.cb_handles[i], ZFS_PROP_MOUNTPOINT,
1396 		    mountpoint, sizeof (mountpoint),
1397 		    NULL, NULL, 0, B_FALSE) != 0) {
1398 			/* no mountpoint */
1399 			continue;
1400 		}
1401 
1402 		/* mountpoint must be a path */
1403 		if (strcmp(mountpoint, ZFS_MOUNTPOINT_NONE) == 0 ||
1404 		    strcmp(mountpoint, ZFS_MOUNTPOINT_LEGACY) == 0) {
1405 			/*
1406 			 * Search mmttab for mountpoint
1407 			 */
1408 
1409 			if (get_legacy_mountpoint(path, dataset,
1410 			    ZFS_MAXPROPLEN, mountpoint,
1411 			    ZFS_MAXPROPLEN) == 0) {
1412 				ret = 1;
1413 				break;
1414 			}
1415 			continue;
1416 		}
1417 
1418 		/* canmount must be set */
1419 		canmount[0] = '\0';
1420 		if (zfs_prop_get(cb.cb_handles[i], ZFS_PROP_CANMOUNT, canmount,
1421 		    sizeof (canmount), NULL, NULL, 0, B_FALSE) != 0 ||
1422 		    strcmp(canmount, "off") == 0)
1423 			continue;
1424 
1425 		/*
1426 		 * have a mountable handle but want to skip those marked none
1427 		 * and legacy
1428 		 */
1429 		if (strcmp(mountpoint, path) == 0) {
1430 			dp = (char *)zfs_get_name(cb.cb_handles[i]);
1431 			if (dp != NULL) {
1432 				if (datasetp != NULL)
1433 					(void) strcpy(datasetp, dp);
1434 				if (mountpointp != NULL)
1435 					(void) strcpy(mountpointp, mountpoint);
1436 				ret = 1;
1437 			}
1438 			break;
1439 		}
1440 
1441 	}
1442 
1443 	return (ret);
1444 }
1445