1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
  24  */
  25 /*
  26  * Copyright 2012 Nexenta Systems, Inc.  All rights reserved.
  27  * Copyright (c) 2012, 2016 by Delphix. All rights reserved.
  28  * Copyright 2017 RackTop Systems.
  29  */
  30 
  31 #include <stdio.h>
  32 #include <libzfs.h>
  33 #include <string.h>
  34 #include <strings.h>
  35 #include <errno.h>
  36 #include <libshare.h>
  37 #include "libshare_impl.h"
  38 #include <libintl.h>
  39 #include <sys/mnttab.h>
  40 #include <sys/mntent.h>
  41 #include <assert.h>
  42 
  43 extern sa_share_t _sa_add_share(sa_group_t, char *, int, int *, uint64_t);
  44 extern sa_group_t _sa_create_zfs_group(sa_group_t, char *);
  45 extern char *sa_fstype(char *);
  46 extern void set_node_attr(void *, char *, char *);
  47 extern int sa_is_share(void *);
  48 extern void sa_update_sharetab_ts(sa_handle_t);
  49 
  50 /*
  51  * File system specific code for ZFS. The original code was stolen
  52  * from the "zfs" command and modified to better suit this library's
  53  * usage.
  54  */
  55 
  56 typedef struct get_all_cbdata {
  57         zfs_handle_t    **cb_handles;
  58         size_t          cb_alloc;
  59         size_t          cb_used;
  60         uint_t          cb_types;
  61 } get_all_cbdata_t;
  62 
  63 /*
  64  * sa_zfs_init(impl_handle)
  65  *
  66  * Initialize an access handle into libzfs.  The handle needs to stay
  67  * around until sa_zfs_fini() in order to maintain the cache of
  68  * mounts.
  69  */
  70 
  71 int
  72 sa_zfs_init(sa_handle_impl_t impl_handle)
  73 {
  74         impl_handle->zfs_libhandle = libzfs_init();
  75         if (impl_handle->zfs_libhandle != NULL) {
  76                 libzfs_print_on_error(impl_handle->zfs_libhandle, B_TRUE);
  77                 return (B_TRUE);
  78         }
  79         return (B_FALSE);
  80 }
  81 
  82 /*
  83  * sa_zfs_fini(impl_handle)
  84  *
  85  * cleanup data structures and the libzfs handle used for accessing
  86  * zfs file share info.
  87  */
  88 
  89 void
  90 sa_zfs_fini(sa_handle_impl_t impl_handle)
  91 {
  92         if (impl_handle->zfs_libhandle != NULL) {
  93                 if (impl_handle->zfs_list != NULL) {
  94                         zfs_handle_t **zhp = impl_handle->zfs_list;
  95                         size_t i;
  96 
  97                         /*
  98                          * Contents of zfs_list need to be freed so we
  99                          * don't lose ZFS handles.
 100                          */
 101                         for (i = 0; i < impl_handle->zfs_list_count; i++) {
 102                                 zfs_close(zhp[i]);
 103                         }
 104                         free(impl_handle->zfs_list);
 105                         impl_handle->zfs_list = NULL;
 106                         impl_handle->zfs_list_count = 0;
 107                 }
 108 
 109                 libzfs_fini(impl_handle->zfs_libhandle);
 110                 impl_handle->zfs_libhandle = NULL;
 111         }
 112 }
 113 
 114 /*
 115  * get_one_filesystem(zfs_handle_t, data)
 116  *
 117  * an iterator function called while iterating through the ZFS
 118  * root. It accumulates into an array of file system handles that can
 119  * be used to derive info about those file systems.
 120  *
 121  * Note that as this function is called, we close all zhp handles that
 122  * are not going to be places into the cp_handles list. We don't want
 123  * to close the ones we are keeping, but all others would be leaked if
 124  * not closed here.
 125  */
 126 
 127 static int
 128 get_one_filesystem(zfs_handle_t *zhp, void *data)
 129 {
 130         get_all_cbdata_t *cbp = data;
 131         zfs_type_t type = zfs_get_type(zhp);
 132 
 133         /*
 134          * Interate over any nested datasets.
 135          */
 136         if (type == ZFS_TYPE_FILESYSTEM &&
 137             zfs_iter_filesystems(zhp, get_one_filesystem, data) != 0) {
 138                 zfs_close(zhp);
 139                 return (1);
 140         }
 141 
 142         /*
 143          * Skip any datasets whose type does not match.
 144          */
 145         if ((type & cbp->cb_types) == 0) {
 146                 zfs_close(zhp);
 147                 return (0);
 148         }
 149 
 150         if (cbp->cb_alloc == cbp->cb_used) {
 151                 zfs_handle_t **handles;
 152 
 153                 if (cbp->cb_alloc == 0)
 154                         cbp->cb_alloc = 64;
 155                 else
 156                         cbp->cb_alloc *= 2;
 157 
 158                 handles = (zfs_handle_t **)calloc(1,
 159                     cbp->cb_alloc * sizeof (void *));
 160 
 161                 if (handles == NULL) {
 162                         zfs_close(zhp);
 163                         return (0);
 164                 }
 165                 if (cbp->cb_handles) {
 166                         bcopy(cbp->cb_handles, handles,
 167                             cbp->cb_used * sizeof (void *));
 168                         free(cbp->cb_handles);
 169                 }
 170 
 171                 cbp->cb_handles = handles;
 172         }
 173 
 174         cbp->cb_handles[cbp->cb_used++] = zhp;
 175 
 176         return (0);
 177 }
 178 
 179 /*
 180  * get_all_filesystems(zfs_handle_t ***fslist, size_t *count)
 181  *
 182  * iterate through all ZFS file systems starting at the root. Returns
 183  * a count and an array of handle pointers. Allocating is only done
 184  * once. The caller does not need to free since it will be done at
 185  * sa_zfs_fini() time.
 186  */
 187 
 188 static void
 189 get_all_filesystems(sa_handle_impl_t impl_handle,
 190     zfs_handle_t ***fslist, size_t *count)
 191 {
 192         get_all_cbdata_t cb = { 0 };
 193         cb.cb_types = ZFS_TYPE_FILESYSTEM;
 194 
 195         if (impl_handle->zfs_list != NULL) {
 196                 *fslist = impl_handle->zfs_list;
 197                 *count = impl_handle->zfs_list_count;
 198                 return;
 199         }
 200 
 201         (void) zfs_iter_root(impl_handle->zfs_libhandle,
 202             get_one_filesystem, &cb);
 203 
 204         impl_handle->zfs_list = *fslist = cb.cb_handles;
 205         impl_handle->zfs_list_count = *count = cb.cb_used;
 206 }
 207 
 208 /*
 209  * mountpoint_compare(a, b)
 210  *
 211  * compares the mountpoint on two zfs file systems handles.
 212  * returns values following strcmp() model.
 213  */
 214 
 215 static int
 216 mountpoint_compare(const void *a, const void *b)
 217 {
 218         zfs_handle_t **za = (zfs_handle_t **)a;
 219         zfs_handle_t **zb = (zfs_handle_t **)b;
 220         char mounta[MAXPATHLEN];
 221         char mountb[MAXPATHLEN];
 222 
 223         verify(zfs_prop_get(*za, ZFS_PROP_MOUNTPOINT, mounta,
 224             sizeof (mounta), NULL, NULL, 0, B_FALSE) == 0);
 225         verify(zfs_prop_get(*zb, ZFS_PROP_MOUNTPOINT, mountb,
 226             sizeof (mountb), NULL, NULL, 0, B_FALSE) == 0);
 227 
 228         return (strcmp(mounta, mountb));
 229 }
 230 
 231 /*
 232  * return legacy mountpoint.  Caller provides space for mountpoint and
 233  * dataset.
 234  */
 235 int
 236 get_legacy_mountpoint(const char *path, char *dataset, size_t dlen,
 237     char *mountpoint, size_t mlen)
 238 {
 239         FILE *fp;
 240         struct mnttab entry;
 241 
 242         if ((fp = fopen(MNTTAB, "r")) == NULL) {
 243                 return (1);
 244         }
 245 
 246         while (getmntent(fp, &entry) == 0) {
 247 
 248                 if (entry.mnt_fstype == NULL ||
 249                     strcmp(entry.mnt_fstype, MNTTYPE_ZFS) != 0)
 250                         continue;
 251 
 252                 if (strcmp(entry.mnt_mountp, path) == 0) {
 253                         if (mlen > 0)
 254                                 (void) strlcpy(mountpoint, entry.mnt_mountp,
 255                                     mlen);
 256                         if (dlen > 0)
 257                                 (void) strlcpy(dataset, entry.mnt_special,
 258                                     dlen);
 259                         break;
 260                 }
 261         }
 262         (void) fclose(fp);
 263         return (1);
 264 }
 265 
 266 
 267 /*
 268  * Verifies that a specific zfs filesystem handle meets the criteria necessary
 269  * to be used by libshare operations. See get_zfs_dataset.
 270  */
 271 static char *
 272 verify_zfs_handle(zfs_handle_t *hdl, const char *path, boolean_t search_mnttab)
 273 {
 274         char mountpoint[ZFS_MAXPROPLEN];
 275         char canmount[ZFS_MAXPROPLEN] = { 0 };
 276         /* must have a mountpoint */
 277         if (zfs_prop_get(hdl, ZFS_PROP_MOUNTPOINT, mountpoint,
 278             sizeof (mountpoint), NULL, NULL, 0, B_FALSE) != 0) {
 279                 /* no mountpoint */
 280                 return (NULL);
 281         }
 282 
 283         /* mountpoint must be a path */
 284         if (strcmp(mountpoint, ZFS_MOUNTPOINT_NONE) == 0 ||
 285             strcmp(mountpoint, ZFS_MOUNTPOINT_LEGACY) == 0) {
 286                 /*
 287                  * Search mmttab for mountpoint and get dataset.
 288                  */
 289 
 290                 if (search_mnttab == B_TRUE &&
 291                     get_legacy_mountpoint(path, mountpoint,
 292                     sizeof (mountpoint), NULL, 0) == 0) {
 293                         return (strdup(mountpoint));
 294                 }
 295                 return (NULL);
 296         }
 297 
 298         /* canmount must be set */
 299         if (zfs_prop_get(hdl, ZFS_PROP_CANMOUNT, canmount,
 300             sizeof (canmount), NULL, NULL, 0, B_FALSE) != 0 ||
 301             strcmp(canmount, "off") == 0)
 302                 return (NULL);
 303 
 304         /*
 305          * have a mountable handle but want to skip those marked none
 306          * and legacy
 307          */
 308         if (strcmp(mountpoint, path) == 0) {
 309                 return (strdup((char *)zfs_get_name(hdl)));
 310         }
 311 
 312         return (NULL);
 313 }
 314 
 315 /*
 316  * get_zfs_dataset(impl_handle, path)
 317  *
 318  * get the name of the ZFS dataset the path is equivalent to.  The
 319  * dataset name is used for get/set of ZFS properties since libzfs
 320  * requires a dataset to do a zfs_open().
 321  */
 322 
 323 static char *
 324 get_zfs_dataset(sa_handle_impl_t impl_handle, char *path,
 325     boolean_t search_mnttab)
 326 {
 327         size_t i, count = 0;
 328         zfs_handle_t **zlist;
 329         char *cutpath;
 330         zfs_handle_t *handle_from_path;
 331         char *ret = NULL;
 332 
 333         /*
 334          * First we optimistically assume that the mount path for the filesystem
 335          * is the same as the name of the filesystem (minus some number of
 336          * leading slashes). If this is true, then zfs_open should properly open
 337          * the filesystem. We duplicate the error checking done later in the
 338          * function for consistency. If anything fails, we resort to the
 339          * (extremely slow) search of all the filesystems.
 340          */
 341         cutpath = path + strspn(path, "/");
 342 
 343         assert(impl_handle->zfs_libhandle != NULL);
 344         libzfs_print_on_error(impl_handle->zfs_libhandle, B_FALSE);
 345         handle_from_path = zfs_open(impl_handle->zfs_libhandle, cutpath,
 346             ZFS_TYPE_FILESYSTEM);
 347         libzfs_print_on_error(impl_handle->zfs_libhandle, B_TRUE);
 348         if (handle_from_path != NULL) {
 349                 ret = verify_zfs_handle(handle_from_path, path, search_mnttab);
 350                 zfs_close(handle_from_path);
 351                 if (ret != NULL) {
 352                         return (ret);
 353                 }
 354         }
 355         /*
 356          * Couldn't find a filesystem optimistically, check all the handles we
 357          * can.
 358          */
 359         get_all_filesystems(impl_handle, &zlist, &count);
 360         for (i = 0; i < count; i++) {
 361                 assert(zlist[i]);
 362                 if ((ret = verify_zfs_handle(zlist[i], path,
 363                     search_mnttab)) != NULL)
 364                         return (ret);
 365         }
 366 
 367         /* Couldn't find a matching dataset */
 368         return (NULL);
 369 }
 370 
 371 /*
 372  * get_zfs_property(dataset, property)
 373  *
 374  * Get the file system property specified from the ZFS dataset.
 375  */
 376 
 377 static char *
 378 get_zfs_property(char *dataset, zfs_prop_t property)
 379 {
 380         zfs_handle_t *handle = NULL;
 381         char shareopts[ZFS_MAXPROPLEN];
 382         libzfs_handle_t *libhandle;
 383 
 384         libhandle = libzfs_init();
 385         if (libhandle != NULL) {
 386                 handle = zfs_open(libhandle, dataset, ZFS_TYPE_FILESYSTEM);
 387                 if (handle != NULL) {
 388                         if (zfs_prop_get(handle, property, shareopts,
 389                             sizeof (shareopts), NULL, NULL, 0,
 390                             B_FALSE) == 0) {
 391                                 zfs_close(handle);
 392                                 libzfs_fini(libhandle);
 393                                 return (strdup(shareopts));
 394                         }
 395                         zfs_close(handle);
 396                 }
 397                 libzfs_fini(libhandle);
 398         }
 399         return (NULL);
 400 }
 401 
 402 /*
 403  * sa_zfs_is_shared(handle, path)
 404  *
 405  * Check to see if the ZFS path provided has the sharenfs option set
 406  * or not.
 407  */
 408 
 409 int
 410 sa_zfs_is_shared(sa_handle_t sahandle, char *path)
 411 {
 412         int ret = 0;
 413         char *dataset;
 414         zfs_handle_t *handle = NULL;
 415         char shareopts[ZFS_MAXPROPLEN];
 416         libzfs_handle_t *libhandle;
 417 
 418         dataset = get_zfs_dataset((sa_handle_t)sahandle, path, B_FALSE);
 419         if (dataset != NULL) {
 420                 libhandle = libzfs_init();
 421                 if (libhandle != NULL) {
 422                         handle = zfs_open(libhandle, dataset,
 423                             ZFS_TYPE_FILESYSTEM);
 424                         if (handle != NULL) {
 425                                 if (zfs_prop_get(handle, ZFS_PROP_SHARENFS,
 426                                     shareopts, sizeof (shareopts), NULL, NULL,
 427                                     0, B_FALSE) == 0 &&
 428                                     strcmp(shareopts, "off") != 0) {
 429                                         ret = 1; /* it is shared */
 430                                 }
 431                                 zfs_close(handle);
 432                         }
 433                         libzfs_fini(libhandle);
 434                 }
 435                 free(dataset);
 436         }
 437         return (ret);
 438 }
 439 
 440 /*
 441  * find_or_create_group(handle, groupname, proto, *err)
 442  *
 443  * While walking the ZFS tree, we need to add shares to a defined
 444  * group. If the group doesn't exist, create it first, making sure it
 445  * is marked as a ZFS group.
 446  *
 447  * Note that all ZFS shares are in a subgroup of the top level group
 448  * called "zfs".
 449  */
 450 
 451 static sa_group_t
 452 find_or_create_group(sa_handle_t handle, char *groupname, char *proto, int *err)
 453 {
 454         sa_group_t group;
 455         sa_optionset_t optionset;
 456         int ret = SA_OK;
 457 
 458         /*
 459          * we check to see if the "zfs" group exists. Since this
 460          * should be the top level group, we don't want the
 461          * parent. This is to make sure the zfs group has been created
 462          * and to created if it hasn't been.
 463          */
 464         group = sa_get_group(handle, groupname);
 465         if (group == NULL) {
 466                 group = sa_create_group(handle, groupname, &ret);
 467 
 468                 /* make sure this is flagged as a ZFS group */
 469                 if (group != NULL)
 470                         ret = sa_set_group_attr(group, "zfs", "true");
 471         }
 472         if (group != NULL) {
 473                 if (proto != NULL) {
 474                         optionset = sa_get_optionset(group, proto);
 475                         if (optionset == NULL)
 476                                 optionset = sa_create_optionset(group, proto);
 477                 }
 478         }
 479         if (err != NULL)
 480                 *err = ret;
 481         return (group);
 482 }
 483 
 484 /*
 485  * find_or_create_zfs_subgroup(groupname, optstring, *err)
 486  *
 487  * ZFS shares will be in a subgroup of the "zfs" master group.  This
 488  * function looks to see if the groupname exists and returns it if it
 489  * does or else creates a new one with the specified name and returns
 490  * that.  The "zfs" group will exist before we get here, but we make
 491  * sure just in case.
 492  *
 493  * err must be a valid pointer.
 494  */
 495 
 496 static sa_group_t
 497 find_or_create_zfs_subgroup(sa_handle_t handle, char *groupname, char *proto,
 498     char *optstring, int *err)
 499 {
 500         sa_group_t group = NULL;
 501         sa_group_t zfs;
 502         char *name;
 503         char *options;
 504 
 505         /* start with the top-level "zfs" group */
 506         zfs = sa_get_group(handle, "zfs");
 507         *err = SA_OK;
 508         if (zfs != NULL) {
 509                 for (group = sa_get_sub_group(zfs); group != NULL;
 510                     group = sa_get_next_group(group)) {
 511                         name = sa_get_group_attr(group, "name");
 512                         if (name != NULL && strcmp(name, groupname) == 0) {
 513                                 /* have the group so break out of here */
 514                                 sa_free_attr_string(name);
 515                                 break;
 516                         }
 517                         if (name != NULL)
 518                                 sa_free_attr_string(name);
 519                 }
 520 
 521                 if (group == NULL) {
 522                         /*
 523                          * Need to create the sub-group since it doesn't exist
 524                          */
 525                         group = _sa_create_zfs_group(zfs, groupname);
 526                         if (group == NULL) {
 527                                 *err = SA_NO_MEMORY;
 528                                 return (NULL);
 529                         }
 530                         set_node_attr(group, "zfs", "true");
 531                 }
 532                 if (strcmp(optstring, "on") == 0)
 533                         optstring = "rw";
 534                 options = strdup(optstring);
 535                 if (options != NULL) {
 536                         *err = sa_parse_legacy_options(group, options,
 537                             proto);
 538                         /* If no optionset, add one. */
 539                         if (sa_get_optionset(group, proto) == NULL)
 540                                 (void) sa_create_optionset(group, proto);
 541 
 542                         /*
 543                          * Do not forget to update an optionset of
 544                          * the parent group so that it contains
 545                          * all protocols its subgroups have.
 546                          */
 547                         if (sa_get_optionset(zfs, proto) == NULL)
 548                                 (void) sa_create_optionset(zfs, proto);
 549 
 550                         free(options);
 551                 } else {
 552                         *err = SA_NO_MEMORY;
 553                 }
 554         }
 555         return (group);
 556 }
 557 
 558 /*
 559  * zfs_construct_resource(share, name, base, dataset)
 560  *
 561  * Add a resource to the share using name as a template. If name ==
 562  * NULL, then construct a name based on the dataset value.
 563  * name.
 564  */
 565 static void
 566 zfs_construct_resource(sa_share_t share, char *dataset)
 567 {
 568         char buff[SA_MAX_RESOURCE_NAME + 1];
 569         int ret = SA_OK;
 570 
 571         (void) snprintf(buff, SA_MAX_RESOURCE_NAME, "%s", dataset);
 572         sa_fix_resource_name(buff);
 573         (void) sa_add_resource(share, buff, SA_SHARE_TRANSIENT, &ret);
 574 }
 575 
 576 /*
 577  * zfs_inherited(handle, source, sourcestr)
 578  *
 579  * handle case of inherited share{nfs,smb}. Pulled out of sa_get_zfs_shares
 580  * for readability.
 581  */
 582 static int
 583 zfs_inherited(sa_handle_t handle, sa_share_t share, char *sourcestr,
 584     char *shareopts, char *mountpoint, char *proto, char *dataset)
 585 {
 586         int doshopt = 0;
 587         int err = SA_OK;
 588         sa_group_t group;
 589         sa_resource_t resource;
 590         uint64_t features;
 591 
 592         /*
 593          * Need to find the "real" parent sub-group. It may not be
 594          * mounted, but it was identified in the "sourcestr"
 595          * variable. The real parent not mounted can occur if
 596          * "canmount=off and sharenfs=on".
 597          */
 598         group = find_or_create_zfs_subgroup(handle, sourcestr, proto,
 599             shareopts, &doshopt);
 600         if (group != NULL) {
 601                 /*
 602                  * We may need the first share for resource
 603                  * prototype. We only care about it if it has a
 604                  * resource that sets a prefix value.
 605                  */
 606                 if (share == NULL)
 607                         share = _sa_add_share(group, mountpoint,
 608                             SA_SHARE_TRANSIENT, &err,
 609                             (uint64_t)SA_FEATURE_NONE);
 610                 /*
 611                  * some options may only be on shares. If the opt
 612                  * string contains one of those, we put it just on the
 613                  * share.
 614                  */
 615                 if (share != NULL && doshopt == SA_PROP_SHARE_ONLY) {
 616                         char *options;
 617                         options = strdup(shareopts);
 618                         if (options != NULL) {
 619                                 set_node_attr(share, "dataset", dataset);
 620                                 err = sa_parse_legacy_options(share, options,
 621                                     proto);
 622                                 set_node_attr(share, "dataset", NULL);
 623                                 free(options);
 624                         }
 625                         if (sa_get_optionset(group, proto) == NULL)
 626                                 (void) sa_create_optionset(group, proto);
 627                 }
 628                 features = sa_proto_get_featureset(proto);
 629                 if (share != NULL && features & SA_FEATURE_RESOURCE) {
 630                         /*
 631                          * We have a share and the protocol requires
 632                          * that at least one resource exist (probably
 633                          * SMB). We need to make sure that there is at
 634                          * least one.
 635                          */
 636                         resource = sa_get_share_resource(share, NULL);
 637                         if (resource == NULL) {
 638                                 zfs_construct_resource(share, dataset);
 639                         }
 640                 }
 641         } else {
 642                 err = SA_NO_MEMORY;
 643         }
 644         return (err);
 645 }
 646 
 647 /*
 648  * zfs_notinherited(group, share, mountpoint, shareopts, proto, dataset,
 649  *     grouperr)
 650  *
 651  * handle case where this is the top of a sub-group in ZFS. Pulled out
 652  * of sa_get_zfs_shares for readability. We need the grouperr from the
 653  * creation of the subgroup to know whether to add the public
 654  * property, etc. to the specific share.
 655  */
 656 static int
 657 zfs_notinherited(sa_group_t group, sa_share_t share, char *mountpoint,
 658     char *shareopts, char *proto, char *dataset, int grouperr)
 659 {
 660         int err = SA_OK;
 661         sa_resource_t resource;
 662         uint64_t features;
 663 
 664         set_node_attr(group, "zfs", "true");
 665         if (share == NULL)
 666                 share = _sa_add_share(group, mountpoint, SA_SHARE_TRANSIENT,
 667                     &err, (uint64_t)SA_FEATURE_NONE);
 668 
 669         if (err != SA_OK)
 670                 return (err);
 671 
 672         if (strcmp(shareopts, "on") == 0)
 673                 shareopts = "";
 674         if (shareopts != NULL) {
 675                 char *options;
 676                 if (grouperr == SA_PROP_SHARE_ONLY) {
 677                         /*
 678                          * Some properties may only be on shares, but
 679                          * due to the ZFS sub-groups being artificial,
 680                          * we sometimes get this and have to deal with
 681                          * it. We do it by attempting to put it on the
 682                          * share.
 683                          */
 684                         options = strdup(shareopts);
 685                         if (options != NULL) {
 686                                 err = sa_parse_legacy_options(share,
 687                                     options, proto);
 688                                 free(options);
 689                         }
 690                 }
 691                 /* Unmark the share's changed state */
 692                 set_node_attr(share, "changed", NULL);
 693         }
 694         features = sa_proto_get_featureset(proto);
 695         if (share != NULL && features & SA_FEATURE_RESOURCE) {
 696                 /*
 697                  * We have a share and the protocol requires that at
 698                  * least one resource exist (probably SMB). We need to
 699                  * make sure that there is at least one.
 700                  */
 701                 resource = sa_get_share_resource(share, NULL);
 702                 if (resource == NULL) {
 703                         zfs_construct_resource(share, dataset);
 704                 }
 705         }
 706         return (err);
 707 }
 708 
 709 /*
 710  * zfs_grp_error(err)
 711  *
 712  * Print group create error, but only once. If err is 0 do the
 713  * print else don't.
 714  */
 715 
 716 static void
 717 zfs_grp_error(int err)
 718 {
 719         if (err == 0) {
 720                 /* only print error once */
 721                 (void) fprintf(stderr, dgettext(TEXT_DOMAIN,
 722                     "Cannot create ZFS subgroup during initialization:"
 723                     " %s\n"), sa_errorstr(SA_SYSTEM_ERR));
 724         }
 725 }
 726 
 727 /*
 728  * zfs_process_share(handle, share, mountpoint, proto, source,
 729  *     shareopts, sourcestr)
 730  *
 731  * Creates the subgroup, if necessary and adds shares, resources
 732  * and properties.
 733  */
 734 int
 735 sa_zfs_process_share(sa_handle_t handle, sa_group_t group, sa_share_t share,
 736     char *mountpoint, char *proto, zprop_source_t source, char *shareopts,
 737     char *sourcestr, char *dataset)
 738 {
 739         int err = SA_OK;
 740 
 741         if (source & ZPROP_SRC_INHERITED) {
 742                 err = zfs_inherited(handle, share, sourcestr, shareopts,
 743                     mountpoint, proto, dataset);
 744         } else {
 745                 group = find_or_create_zfs_subgroup(handle, dataset, proto,
 746                     shareopts, &err);
 747                 if (group == NULL) {
 748                         static boolean_t reported_error = B_FALSE;
 749                         /*
 750                          * There is a problem, but we can't do
 751                          * anything about it at this point so we issue
 752                          * a warning and move on.
 753                          */
 754                         zfs_grp_error(reported_error);
 755                         reported_error = B_TRUE;
 756                 }
 757                 set_node_attr(group, "zfs", "true");
 758                 /*
 759                  * Add share with local opts via zfs_notinherited.
 760                  */
 761                 err = zfs_notinherited(group, share, mountpoint, shareopts,
 762                     proto, dataset, err);
 763         }
 764         return (err);
 765 }
 766 
 767 /*
 768  * Walk the mnttab for all zfs mounts and determine which are
 769  * shared. Find or create the appropriate group/sub-group to contain
 770  * the shares.
 771  *
 772  * All shares are in a sub-group that will hold the properties. This
 773  * allows representing the inherited property model.
 774  *
 775  * One area of complication is if "sharenfs" is set at one level of
 776  * the directory tree and "sharesmb" is set at a different level, the
 777  * a sub-group must be formed at the lower level for both
 778  * protocols. That is the nature of the problem in CR 6667349.
 779  */
 780 static int
 781 sa_get_zfs_share_common(sa_handle_t handle, zfs_handle_t *fs_handle, char *path,
 782     sa_group_t zfsgroup)
 783 {
 784         boolean_t smb, nfs;
 785         boolean_t smb_inherited, nfs_inherited;
 786         char nfsshareopts[ZFS_MAXPROPLEN];
 787         char smbshareopts[ZFS_MAXPROPLEN];
 788         char nfssourcestr[ZFS_MAXPROPLEN];
 789         char smbsourcestr[ZFS_MAXPROPLEN];
 790         char mountpoint[ZFS_MAXPROPLEN];
 791         int err = SA_OK;
 792         zprop_source_t source;
 793         sa_share_t share;
 794         char *dataset;
 795 
 796         source = ZPROP_SRC_ALL;
 797         /* If no mountpoint, skip. */
 798         if (zfs_prop_get(fs_handle, ZFS_PROP_MOUNTPOINT,
 799             mountpoint, sizeof (mountpoint), NULL, NULL, 0,
 800             B_FALSE) != 0)
 801                 return (SA_SYSTEM_ERR);
 802 
 803         if (path != NULL)
 804                 (void) strncpy(path, mountpoint, sizeof (mountpoint));
 805         /*
 806          * zfs_get_name value must not be freed. It is just a
 807          * pointer to a value in the handle.
 808          */
 809         if ((dataset = (char *)zfs_get_name(fs_handle)) == NULL)
 810                 return (SA_SYSTEM_ERR);
 811 
 812         /*
 813          * only deal with "mounted" file systems since
 814          * unmounted file systems can't actually be shared.
 815          */
 816 
 817         if (!zfs_is_mounted(fs_handle, NULL))
 818                 return (SA_SYSTEM_ERR);
 819 
 820         nfs = nfs_inherited = B_FALSE;
 821 
 822         if (zfs_prop_get(fs_handle, ZFS_PROP_SHARENFS, nfsshareopts,
 823             sizeof (nfsshareopts), &source, nfssourcestr,
 824             ZFS_MAXPROPLEN, B_FALSE) == 0 &&
 825             strcmp(nfsshareopts, "off") != 0) {
 826                 if (source & ZPROP_SRC_INHERITED)
 827                         nfs_inherited = B_TRUE;
 828                 else
 829                         nfs = B_TRUE;
 830         }
 831 
 832         smb = smb_inherited = B_FALSE;
 833         if (zfs_prop_get(fs_handle, ZFS_PROP_SHARESMB, smbshareopts,
 834             sizeof (smbshareopts), &source, smbsourcestr,
 835             ZFS_MAXPROPLEN, B_FALSE) == 0 &&
 836             strcmp(smbshareopts, "off") != 0) {
 837                 if (source & ZPROP_SRC_INHERITED)
 838                         smb_inherited = B_TRUE;
 839                 else
 840                         smb = B_TRUE;
 841         }
 842 
 843         /*
 844          * If the mountpoint is already shared, it must be a
 845          * non-ZFS share. We want to remove the share from its
 846          * parent group and reshare it under ZFS.
 847          */
 848         share = sa_find_share(handle, mountpoint);
 849         if (share != NULL &&
 850             (nfs || smb || nfs_inherited || smb_inherited)) {
 851                 err = sa_remove_share(share);
 852                 share = NULL;
 853         }
 854 
 855         /*
 856          * At this point, we have the information needed to
 857          * determine what to do with the share.
 858          *
 859          * If smb or nfs is set, we have a new sub-group.
 860          * If smb_inherit and/or nfs_inherit is set, then
 861          * place on an existing sub-group. If both are set,
 862          * the existing sub-group is the closest up the tree.
 863          */
 864         if (nfs || smb) {
 865                 /*
 866                  * Non-inherited is the straightforward
 867                  * case. sa_zfs_process_share handles it
 868                  * directly. Make sure that if the "other"
 869                  * protocol is inherited, that we treat it as
 870                  * non-inherited as well.
 871                  */
 872                 if (nfs || nfs_inherited) {
 873                         err = sa_zfs_process_share(handle, zfsgroup,
 874                             share, mountpoint, "nfs",
 875                             0, nfsshareopts,
 876                             nfssourcestr, dataset);
 877                         share = sa_find_share(handle, mountpoint);
 878                 }
 879                 if (smb || smb_inherited) {
 880                         err = sa_zfs_process_share(handle, zfsgroup,
 881                             share, mountpoint, "smb",
 882                             0, smbshareopts,
 883                             smbsourcestr, dataset);
 884                 }
 885         } else if (nfs_inherited || smb_inherited) {
 886                 char *grpdataset;
 887                 /*
 888                  * If we only have inherited groups, it is
 889                  * important to find the closer of the two if
 890                  * the protocols are set at different
 891                  * levels. The closest sub-group is the one we
 892                  * want to work with.
 893                  */
 894                 if (nfs_inherited && smb_inherited) {
 895                         if (strcmp(nfssourcestr, smbsourcestr) <= 0)
 896                                 grpdataset = nfssourcestr;
 897                         else
 898                                 grpdataset = smbsourcestr;
 899                 } else if (nfs_inherited) {
 900                         grpdataset = nfssourcestr;
 901                 } else if (smb_inherited) {
 902                         grpdataset = smbsourcestr;
 903                 }
 904                 if (nfs_inherited) {
 905                         err = sa_zfs_process_share(handle, zfsgroup,
 906                             share, mountpoint, "nfs",
 907                             ZPROP_SRC_INHERITED, nfsshareopts,
 908                             grpdataset, dataset);
 909                         share = sa_find_share(handle, mountpoint);
 910                 }
 911                 if (smb_inherited) {
 912                         err = sa_zfs_process_share(handle, zfsgroup,
 913                             share, mountpoint, "smb",
 914                             ZPROP_SRC_INHERITED, smbshareopts,
 915                             grpdataset, dataset);
 916                 }
 917         }
 918         return (err);
 919 }
 920 
 921 /*
 922  * Handles preparing generic objects such as the libzfs handle and group for
 923  * sa_get_one_zfs_share, sa_get_zfs_share_for_name, and sa_get_zfs_shares.
 924  */
 925 static int
 926 prep_zfs_handle_and_group(sa_handle_t handle, char *groupname,
 927     libzfs_handle_t **zfs_libhandle, sa_group_t *zfsgroup, int *err)
 928 {
 929         /*
 930          * If we can't access libzfs, don't bother doing anything.
 931          */
 932         *zfs_libhandle = ((sa_handle_impl_t)handle)->zfs_libhandle;
 933         if (*zfs_libhandle == NULL)
 934                 return (SA_SYSTEM_ERR);
 935 
 936         *zfsgroup = find_or_create_group(handle, groupname, NULL, err);
 937         return (SA_OK);
 938 }
 939 
 940 /*
 941  * The O.G. zfs share preparation function. This initializes all zfs shares for
 942  * use with libshare.
 943  */
 944 int
 945 sa_get_zfs_shares(sa_handle_t handle, char *groupname)
 946 {
 947         sa_group_t zfsgroup;
 948         zfs_handle_t **zlist;
 949         size_t count = 0;
 950         libzfs_handle_t *zfs_libhandle;
 951         int err;
 952 
 953         if ((err = prep_zfs_handle_and_group(handle, groupname, &zfs_libhandle,
 954             &zfsgroup, &err)) != SA_OK) {
 955                 return (err);
 956         }
 957         /* Not an error, this could be a legacy condition */
 958         if (zfsgroup == NULL)
 959                 return (SA_OK);
 960 
 961         /*
 962          * need to walk the mounted ZFS pools and datasets to
 963          * find shares that are possible.
 964          */
 965         get_all_filesystems((sa_handle_impl_t)handle, &zlist, &count);
 966         qsort(zlist, count, sizeof (void *), mountpoint_compare);
 967 
 968         for (int i = 0; i < count; i++) {
 969                 err = sa_get_zfs_share_common(handle, zlist[i], NULL, zfsgroup);
 970         }
 971         /*
 972          * Don't need to free the "zlist" variable since it is only a
 973          * pointer to a cached value that will be freed when
 974          * sa_fini() is called.
 975          */
 976         return (err);
 977 }
 978 
 979 /*
 980  * Initializes only the handles specified in the sharearg for use with libshare.
 981  * This is used as a performance optimization relative to sa_get_zfs_shares.
 982  */
 983 int
 984 sa_get_one_zfs_share(sa_handle_t handle, char *groupname,
 985     sa_init_selective_arg_t *sharearg, char ***paths, size_t *paths_len)
 986 {
 987         sa_group_t zfsgroup;
 988         libzfs_handle_t *zfs_libhandle;
 989         int err;
 990 
 991         if ((err = prep_zfs_handle_and_group(handle, groupname, &zfs_libhandle,
 992             &zfsgroup, &err)) != SA_OK) {
 993                 return (err);
 994         }
 995         /* Not an error, this could be a legacy condition */
 996         if (zfsgroup == NULL)
 997                 return (SA_OK);
 998 
 999         *paths_len = sharearg->zhandle_len;
1000         *paths = calloc(*paths_len, sizeof (char *));
1001         for (int i = 0; i < sharearg->zhandle_len; ++i) {
1002                 zfs_handle_t *fs_handle =
1003                     ((zfs_handle_t **)(sharearg->zhandle_arr))[i];
1004                 if (fs_handle == NULL) {
1005                         /* Free non-null elements of the paths array */
1006                         for (int free_idx = 0; free_idx < *paths_len;
1007                             ++free_idx) {
1008                                 if ((*paths)[free_idx] != NULL)
1009                                         free((*paths)[free_idx]);
1010                         }
1011                         free(*paths);
1012                         *paths = NULL;
1013                         *paths_len = 0;
1014                         return (SA_SYSTEM_ERR);
1015                 }
1016                 (*paths)[i] = malloc(sizeof (char) * ZFS_MAXPROPLEN);
1017                 err |= sa_get_zfs_share_common(handle, fs_handle, (*paths)[i],
1018                     zfsgroup);
1019         }
1020 
1021         return (err);
1022 }
1023 
1024 /*
1025  * Initializes only the share with the specified sharename for use with
1026  * libshare.
1027  */
1028 int
1029 sa_get_zfs_share_for_name(sa_handle_t handle, char *groupname,
1030     const char *sharename, char *outpath)
1031 {
1032         sa_group_t zfsgroup;
1033         libzfs_handle_t *zfs_libhandle;
1034         int err;
1035 
1036         if ((err = prep_zfs_handle_and_group(handle, groupname, &zfs_libhandle,
1037             &zfsgroup, &err)) != SA_OK) {
1038                 return (err);
1039         }
1040         /* Not an error, this could be a legacy condition */
1041         if (zfsgroup == NULL)
1042                 return (SA_OK);
1043 
1044         zfs_handle_t *fs_handle = zfs_open(zfs_libhandle,
1045             sharename + strspn(sharename, "/"), ZFS_TYPE_DATASET);
1046         if (fs_handle == NULL)
1047                 return (SA_SYSTEM_ERR);
1048 
1049         err = sa_get_zfs_share_common(handle, fs_handle, outpath, zfsgroup);
1050         zfs_close(fs_handle);
1051         return (err);
1052 }
1053 
1054 
1055 
1056 #define COMMAND         "/usr/sbin/zfs"
1057 
1058 /*
1059  * sa_zfs_set_sharenfs(group, path, on)
1060  *
1061  * Update the "sharenfs" property on the path. If on is true, then set
1062  * to the properties on the group or "on" if no properties are
1063  * defined. Set to "off" if on is false.
1064  */
1065 
1066 int
1067 sa_zfs_set_sharenfs(sa_group_t group, char *path, int on)
1068 {
1069         int ret = SA_NOT_IMPLEMENTED;
1070         char *command;
1071 
1072         command = malloc(ZFS_MAXPROPLEN * 2);
1073         if (command != NULL) {
1074                 char *opts = NULL;
1075                 char *dataset = NULL;
1076                 FILE *pfile;
1077                 sa_handle_impl_t impl_handle;
1078                 /* for now, NFS is always available for "zfs" */
1079                 if (on) {
1080                         opts = sa_proto_legacy_format("nfs", group, 1);
1081                         if (opts != NULL && strlen(opts) == 0) {
1082                                 free(opts);
1083                                 opts = strdup("on");
1084                         }
1085                 }
1086 
1087                 impl_handle = (sa_handle_impl_t)sa_find_group_handle(group);
1088                 assert(impl_handle != NULL);
1089                 if (impl_handle != NULL)
1090                         dataset = get_zfs_dataset(impl_handle, path, B_FALSE);
1091                 else
1092                         ret = SA_SYSTEM_ERR;
1093 
1094                 if (dataset != NULL) {
1095                         (void) snprintf(command, ZFS_MAXPROPLEN * 2,
1096                             "%s set sharenfs=\"%s\" %s", COMMAND,
1097                             opts != NULL ? opts : "off", dataset);
1098                         pfile = popen(command, "r");
1099                         if (pfile != NULL) {
1100                                 ret = pclose(pfile);
1101                                 if (ret != 0)
1102                                         ret = SA_SYSTEM_ERR;
1103                         }
1104                 }
1105                 if (opts != NULL)
1106                         free(opts);
1107                 if (dataset != NULL)
1108                         free(dataset);
1109                 free(command);
1110         }
1111         return (ret);
1112 }
1113 
1114 /*
1115  * add_resources(share, opt)
1116  *
1117  * Add resource properties to those in "opt".  Resources are prefixed
1118  * with name=resourcename.
1119  */
1120 static char *
1121 add_resources(sa_share_t share, char *opt)
1122 {
1123         char *newopt = NULL;
1124         char *propstr;
1125         sa_resource_t resource;
1126 
1127         newopt = strdup(opt);
1128         if (newopt == NULL)
1129                 return (newopt);
1130 
1131         for (resource = sa_get_share_resource(share, NULL);
1132             resource != NULL;
1133             resource = sa_get_next_resource(resource)) {
1134                 char *name;
1135                 size_t size;
1136 
1137                 name = sa_get_resource_attr(resource, "name");
1138                 if (name == NULL) {
1139                         free(newopt);
1140                         return (NULL);
1141                 }
1142                 size = strlen(name) + strlen(opt) + sizeof ("name=") + 1;
1143                 newopt = calloc(1, size);
1144                 if (newopt != NULL)
1145                         (void) snprintf(newopt, size, "%s,name=%s", opt, name);
1146                 sa_free_attr_string(name);
1147                 free(opt);
1148                 opt = newopt;
1149                 propstr = sa_proto_legacy_format("smb", resource, 0);
1150                 if (propstr == NULL) {
1151                         free(opt);
1152                         return (NULL);
1153                 }
1154                 size = strlen(propstr) + strlen(opt) + 2;
1155                 newopt = calloc(1, size);
1156                 if (newopt != NULL)
1157                         (void) snprintf(newopt, size, "%s,%s", opt, propstr);
1158                 free(opt);
1159                 opt = newopt;
1160         }
1161         return (opt);
1162 }
1163 
1164 /*
1165  * sa_zfs_set_sharesmb(group, path, on)
1166  *
1167  * Update the "sharesmb" property on the path. If on is true, then set
1168  * to the properties on the group or "on" if no properties are
1169  * defined. Set to "off" if on is false.
1170  */
1171 
1172 int
1173 sa_zfs_set_sharesmb(sa_group_t group, char *path, int on)
1174 {
1175         int ret = SA_NOT_IMPLEMENTED;
1176         char *command;
1177         sa_share_t share;
1178 
1179         /* In case SMB not enabled */
1180         if (sa_get_optionset(group, "smb") == NULL)
1181                 return (SA_NOT_SUPPORTED);
1182 
1183         command = malloc(ZFS_MAXPROPLEN * 2);
1184         if (command != NULL) {
1185                 char *opts = NULL;
1186                 char *dataset = NULL;
1187                 FILE *pfile;
1188                 sa_handle_impl_t impl_handle;
1189 
1190                 if (on) {
1191                         char *newopt;
1192 
1193                         share = sa_get_share(group, NULL);
1194                         opts = sa_proto_legacy_format("smb", share, 1);
1195                         if (opts != NULL && strlen(opts) == 0) {
1196                                 free(opts);
1197                                 opts = strdup("on");
1198                         }
1199                         newopt = add_resources(opts, share);
1200                         free(opts);
1201                         opts = newopt;
1202                 }
1203 
1204                 impl_handle = (sa_handle_impl_t)sa_find_group_handle(group);
1205                 assert(impl_handle != NULL);
1206                 if (impl_handle != NULL)
1207                         dataset = get_zfs_dataset(impl_handle, path, B_FALSE);
1208                 else
1209                         ret = SA_SYSTEM_ERR;
1210 
1211                 if (dataset != NULL) {
1212                         (void) snprintf(command, ZFS_MAXPROPLEN * 2,
1213                             "echo %s set sharesmb=\"%s\" %s", COMMAND,
1214                             opts != NULL ? opts : "off", dataset);
1215                         pfile = popen(command, "r");
1216                         if (pfile != NULL) {
1217                                 ret = pclose(pfile);
1218                                 if (ret != 0)
1219                                         ret = SA_SYSTEM_ERR;
1220                         }
1221                 }
1222                 if (opts != NULL)
1223                         free(opts);
1224                 if (dataset != NULL)
1225                         free(dataset);
1226                 free(command);
1227         }
1228         return (ret);
1229 }
1230 
1231 /*
1232  * sa_zfs_update(group)
1233  *
1234  * call back to ZFS to update the share if necessary.
1235  * Don't do it if it isn't a real change.
1236  */
1237 int
1238 sa_zfs_update(sa_group_t group)
1239 {
1240         sa_optionset_t protopt;
1241         sa_group_t parent;
1242         char *command;
1243         char *optstring;
1244         int ret = SA_OK;
1245         int doupdate = 0;
1246         FILE *pfile;
1247 
1248         if (sa_is_share(group))
1249                 parent = sa_get_parent_group(group);
1250         else
1251                 parent = group;
1252 
1253         if (parent != NULL) {
1254                 command = malloc(ZFS_MAXPROPLEN * 2);
1255                 if (command == NULL)
1256                         return (SA_NO_MEMORY);
1257 
1258                 *command = '\0';
1259                 for (protopt = sa_get_optionset(parent, NULL); protopt != NULL;
1260                     protopt = sa_get_next_optionset(protopt)) {
1261 
1262                         char *proto = sa_get_optionset_attr(protopt, "type");
1263                         char *path;
1264                         char *dataset = NULL;
1265                         char *zfsopts = NULL;
1266 
1267                         if (sa_is_share(group)) {
1268                                 path = sa_get_share_attr((sa_share_t)group,
1269                                     "path");
1270                                 if (path != NULL) {
1271                                         sa_handle_impl_t impl_handle;
1272 
1273                                         impl_handle = sa_find_group_handle(
1274                                             group);
1275                                         if (impl_handle != NULL)
1276                                                 dataset = get_zfs_dataset(
1277                                                     impl_handle, path, B_FALSE);
1278                                         else
1279                                                 ret = SA_SYSTEM_ERR;
1280 
1281                                         sa_free_attr_string(path);
1282                                 }
1283                         } else {
1284                                 dataset = sa_get_group_attr(group, "name");
1285                         }
1286                         /* update only when there is an optstring found */
1287                         doupdate = 0;
1288                         if (proto != NULL && dataset != NULL) {
1289                                 optstring = sa_proto_legacy_format(proto,
1290                                     group, 1);
1291                                 zfsopts = get_zfs_property(dataset,
1292                                     ZFS_PROP_SHARENFS);
1293 
1294                                 if (optstring != NULL && zfsopts != NULL) {
1295                                         if (strcmp(optstring, zfsopts) != 0)
1296                                                 doupdate++;
1297                                 }
1298                                 if (doupdate) {
1299                                         if (optstring != NULL &&
1300                                             strlen(optstring) > 0) {
1301                                                 (void) snprintf(command,
1302                                                     ZFS_MAXPROPLEN * 2,
1303                                                     "%s set share%s=%s %s",
1304                                                     COMMAND, proto,
1305                                                     optstring, dataset);
1306                                         } else {
1307                                                 (void) snprintf(command,
1308                                                     ZFS_MAXPROPLEN * 2,
1309                                                     "%s set share%s=on %s",
1310                                                     COMMAND, proto,
1311                                                     dataset);
1312                                         }
1313                                         pfile = popen(command, "r");
1314                                         if (pfile != NULL)
1315                                                 ret = pclose(pfile);
1316                                         switch (ret) {
1317                                         default:
1318                                         case 1:
1319                                                 ret = SA_SYSTEM_ERR;
1320                                                 break;
1321                                         case 2:
1322                                                 ret = SA_SYNTAX_ERR;
1323                                                 break;
1324                                         case 0:
1325                                                 break;
1326                                         }
1327                                 }
1328                                 if (optstring != NULL)
1329                                         free(optstring);
1330                                 if (zfsopts != NULL)
1331                                         free(zfsopts);
1332                         }
1333                         if (proto != NULL)
1334                                 sa_free_attr_string(proto);
1335                         if (dataset != NULL)
1336                                 free(dataset);
1337                 }
1338                 free(command);
1339         }
1340         return (ret);
1341 }
1342 
1343 /*
1344  * sa_group_is_zfs(group)
1345  *
1346  * Given the group, determine if the zfs attribute is set.
1347  */
1348 
1349 int
1350 sa_group_is_zfs(sa_group_t group)
1351 {
1352         char *zfs;
1353         int ret = 0;
1354 
1355         zfs = sa_get_group_attr(group, "zfs");
1356         if (zfs != NULL) {
1357                 ret = 1;
1358                 sa_free_attr_string(zfs);
1359         }
1360         return (ret);
1361 }
1362 
1363 /*
1364  * sa_path_is_zfs(path)
1365  *
1366  * Check to see if the file system path represents is of type "zfs".
1367  */
1368 
1369 int
1370 sa_path_is_zfs(char *path)
1371 {
1372         char *fstype;
1373         int ret = 0;
1374 
1375         fstype = sa_fstype(path);
1376         if (fstype != NULL && strcmp(fstype, "zfs") == 0)
1377                 ret = 1;
1378         if (fstype != NULL)
1379                 sa_free_fstype(fstype);
1380         return (ret);
1381 }
1382 
1383 int
1384 sa_sharetab_fill_zfs(sa_share_t share, share_t *sh, char *proto)
1385 {
1386         char *path;
1387 
1388         /* Make sure path is valid */
1389 
1390         path = sa_get_share_attr(share, "path");
1391         if (path != NULL) {
1392                 (void) memset(sh, 0, sizeof (sh));
1393                 (void) sa_fillshare(share, proto, sh);
1394                 sa_free_attr_string(path);
1395                 return (0);
1396         } else
1397                 return (1);
1398 }
1399 
1400 #define SMAX(i, j)      \
1401         if ((j) > (i)) { \
1402                 (i) = (j); \
1403         }
1404 
1405 int
1406 sa_share_zfs(sa_share_t share, sa_resource_t resource, char *path, share_t *sh,
1407     void *exportdata, zfs_share_op_t operation)
1408 {
1409         libzfs_handle_t *libhandle;
1410         sa_group_t group;
1411         sa_handle_t sahandle;
1412         char *dataset;
1413         int err = EINVAL;
1414         int i, j;
1415         char newpath[MAXPATHLEN];
1416         char *pathp;
1417 
1418         /*
1419          * First find the dataset name
1420          */
1421         if ((group = sa_get_parent_group(share)) == NULL)  {
1422                 return (EINVAL);
1423         }
1424         if ((sahandle = sa_find_group_handle(group)) == NULL) {
1425                 return (EINVAL);
1426         }
1427 
1428         /*
1429          * If get_zfs_dataset fails, see if it is a subdirectory
1430          */
1431 
1432         pathp = path;
1433         while ((dataset = get_zfs_dataset(sahandle, pathp, B_TRUE)) == NULL) {
1434                 char *p;
1435 
1436                 if (pathp == path) {
1437                         (void) strlcpy(newpath, path, sizeof (newpath));
1438                         pathp = newpath;
1439                 }
1440 
1441                 /*
1442                  * Make sure only one leading '/' This condition came
1443                  * about when using HAStoragePlus which insisted on
1444                  * putting an extra leading '/' in the ZFS path
1445                  * name. The problem is fixed in other areas, but this
1446                  * will catch any other ways that a double slash might
1447                  * get introduced.
1448                  */
1449                 while (*pathp == '/' && *(pathp + 1) == '/')
1450                         pathp++;
1451 
1452                 /*
1453                  * chop off part of path, but if we are at root then
1454                  * make sure path is a /
1455                  */
1456                 if ((strlen(pathp) > 1) && (p = strrchr(pathp, '/'))) {
1457                         if (pathp == p) {
1458                                 *(p + 1) = '\0';  /* skip over /, root case */
1459                         } else {
1460                                 *p = '\0';
1461                         }
1462                 } else {
1463                         return (EINVAL);
1464                 }
1465         }
1466 
1467         libhandle = libzfs_init();
1468         if (libhandle != NULL) {
1469                 char *resource_name;
1470 
1471                 i = (sh->sh_path ? strlen(sh->sh_path) : 0);
1472                 sh->sh_size = i;
1473 
1474                 j = (sh->sh_res ? strlen(sh->sh_res) : 0);
1475                 sh->sh_size += j;
1476                 SMAX(i, j);
1477 
1478                 j = (sh->sh_fstype ? strlen(sh->sh_fstype) : 0);
1479                 sh->sh_size += j;
1480                 SMAX(i, j);
1481 
1482                 j = (sh->sh_opts ? strlen(sh->sh_opts) : 0);
1483                 sh->sh_size += j;
1484                 SMAX(i, j);
1485 
1486                 j = (sh->sh_descr ? strlen(sh->sh_descr) : 0);
1487                 sh->sh_size += j;
1488                 SMAX(i, j);
1489 
1490                 resource_name = sa_get_resource_attr(resource, "name");
1491 
1492                 err = zfs_deleg_share_nfs(libhandle, dataset, path,
1493                     resource_name, exportdata, sh, i, operation);
1494                 if (err == SA_OK)
1495                         sa_update_sharetab_ts(sahandle);
1496                 else
1497                         err = errno;
1498                 if (resource_name)
1499                         sa_free_attr_string(resource_name);
1500 
1501                 libzfs_fini(libhandle);
1502         }
1503         free(dataset);
1504         return (err);
1505 }
1506 
1507 /*
1508  * sa_get_zfs_handle(handle)
1509  *
1510  * Given an sa_handle_t, return the libzfs_handle_t *. This is only
1511  * used internally by libzfs. Needed in order to avoid including
1512  * libshare_impl.h in libzfs.
1513  */
1514 
1515 libzfs_handle_t *
1516 sa_get_zfs_handle(sa_handle_t handle)
1517 {
1518         sa_handle_impl_t implhandle = (sa_handle_impl_t)handle;
1519 
1520         return (implhandle->zfs_libhandle);
1521 }
1522 
1523 /*
1524  * sa_get_zfs_info(libzfs, path, mountpoint, dataset)
1525  *
1526  * Find the ZFS dataset and mountpoint for a given path
1527  */
1528 int
1529 sa_zfs_get_info(libzfs_handle_t *libzfs, char *path, char *mountpointp,
1530     char *datasetp)
1531 {
1532         get_all_cbdata_t cb = { 0 };
1533         int i;
1534         char mountpoint[ZFS_MAXPROPLEN];
1535         char dataset[ZFS_MAXPROPLEN];
1536         char canmount[ZFS_MAXPROPLEN];
1537         char *dp;
1538         int count;
1539         int ret = 0;
1540 
1541         cb.cb_types = ZFS_TYPE_FILESYSTEM;
1542 
1543         if (libzfs == NULL)
1544                 return (0);
1545 
1546         (void) zfs_iter_root(libzfs, get_one_filesystem, &cb);
1547         count = cb.cb_used;
1548 
1549         qsort(cb.cb_handles, count, sizeof (void *), mountpoint_compare);
1550         for (i = 0; i < count; i++) {
1551                 /* must have a mountpoint */
1552                 if (zfs_prop_get(cb.cb_handles[i], ZFS_PROP_MOUNTPOINT,
1553                     mountpoint, sizeof (mountpoint),
1554                     NULL, NULL, 0, B_FALSE) != 0) {
1555                         /* no mountpoint */
1556                         continue;
1557                 }
1558 
1559                 /* mountpoint must be a path */
1560                 if (strcmp(mountpoint, ZFS_MOUNTPOINT_NONE) == 0 ||
1561                     strcmp(mountpoint, ZFS_MOUNTPOINT_LEGACY) == 0) {
1562                         /*
1563                          * Search mmttab for mountpoint
1564                          */
1565 
1566                         if (get_legacy_mountpoint(path, dataset,
1567                             ZFS_MAXPROPLEN, mountpoint,
1568                             ZFS_MAXPROPLEN) == 0) {
1569                                 ret = 1;
1570                                 break;
1571                         }
1572                         continue;
1573                 }
1574 
1575                 /* canmount must be set */
1576                 canmount[0] = '\0';
1577                 if (zfs_prop_get(cb.cb_handles[i], ZFS_PROP_CANMOUNT, canmount,
1578                     sizeof (canmount), NULL, NULL, 0, B_FALSE) != 0 ||
1579                     strcmp(canmount, "off") == 0)
1580                         continue;
1581 
1582                 /*
1583                  * have a mountable handle but want to skip those marked none
1584                  * and legacy
1585                  */
1586                 if (strcmp(mountpoint, path) == 0) {
1587                         dp = (char *)zfs_get_name(cb.cb_handles[i]);
1588                         if (dp != NULL) {
1589                                 if (datasetp != NULL)
1590                                         (void) strcpy(datasetp, dp);
1591                                 if (mountpointp != NULL)
1592                                         (void) strcpy(mountpointp, mountpoint);
1593                                 ret = 1;
1594                         }
1595                         break;
1596                 }
1597 
1598         }
1599 
1600         return (ret);
1601 }
1602 
1603 /*
1604  * This method builds values for "sharesmb" property from the
1605  * nvlist argument. The values are returned in sharesmb_val variable.
1606  */
1607 static int
1608 sa_zfs_sprintf_new_prop(nvlist_t *nvl, char *sharesmb_val)
1609 {
1610         char cur_val[MAXPATHLEN];
1611         char *name, *val;
1612         nvpair_t *cur;
1613         int err = 0;
1614 
1615         cur = nvlist_next_nvpair(nvl, NULL);
1616         while (cur != NULL) {
1617                 name = nvpair_name(cur);
1618                 err = nvpair_value_string(cur, &val);
1619                 if ((err != 0) || (name == NULL) || (val == NULL))
1620                         return (-1);
1621 
1622                 (void) snprintf(cur_val, MAXPATHLEN, "%s=%s,", name, val);
1623                 (void) strlcat(sharesmb_val, cur_val, MAXPATHLEN);
1624 
1625                 cur = nvlist_next_nvpair(nvl, cur);
1626         }
1627 
1628         return (0);
1629 }
1630 
1631 /*
1632  * This method builds values for "sharesmb" property from values
1633  * already existing on the share. The properties set via sa_zfs_sprint_new_prop
1634  * method are passed in sharesmb_val. If a existing property is already
1635  * set via sa_zfs_sprint_new_prop method, then they are not appended
1636  * to the sharesmb_val string. The returned sharesmb_val string is a combination
1637  * of new and existing values for 'sharesmb' property.
1638  */
1639 static int
1640 sa_zfs_sprintf_existing_prop(zfs_handle_t *handle, char *sharesmb_val)
1641 {
1642         char shareopts[ZFS_MAXPROPLEN], cur_val[MAXPATHLEN];
1643         char *token, *last, *value;
1644 
1645         if (zfs_prop_get(handle, ZFS_PROP_SHARESMB, shareopts,
1646             sizeof (shareopts), NULL, NULL, 0, B_FALSE) != 0)
1647                 return (-1);
1648 
1649         if (strstr(shareopts, "=") == NULL)
1650                 return (0);
1651 
1652         for (token = strtok_r(shareopts, ",", &last); token != NULL;
1653             token = strtok_r(NULL, ",", &last)) {
1654                 value = strchr(token, '=');
1655                 if (value == NULL)
1656                         return (-1);
1657                 *value++ = '\0';
1658 
1659                 (void) snprintf(cur_val, MAXPATHLEN, "%s=", token);
1660                 if (strstr(sharesmb_val, cur_val) == NULL) {
1661                         (void) strlcat(cur_val, value, MAXPATHLEN);
1662                         (void) strlcat(cur_val, ",", MAXPATHLEN);
1663                         (void) strlcat(sharesmb_val, cur_val, MAXPATHLEN);
1664                 }
1665         }
1666 
1667         return (0);
1668 }
1669 
1670 /*
1671  * Sets the share properties on a ZFS share. For now, this method sets only
1672  * the "sharesmb" property.
1673  *
1674  * This method includes building a comma seperated name-value string to be
1675  * set on the "sharesmb" property of a ZFS share. This name-value string is
1676  * build in 2 steps:
1677  *    - New property values given as name-value pair are set first.
1678  *    - Existing optionset properties, which are not part of the new properties
1679  *      passed in step 1, are appended to the newly set properties.
1680  */
1681 int
1682 sa_zfs_setprop(sa_handle_t handle, char *path, nvlist_t *nvl)
1683 {
1684         zfs_handle_t *z_fs;
1685         libzfs_handle_t *z_lib;
1686         char sharesmb_val[MAXPATHLEN];
1687         char *dataset, *lastcomma;
1688 
1689         if (nvlist_empty(nvl))
1690                 return (0);
1691 
1692         if ((handle == NULL) || (path == NULL))
1693                 return (-1);
1694 
1695         if ((dataset = get_zfs_dataset(handle, path, B_FALSE)) == NULL)
1696                 return (-1);
1697 
1698         if ((z_lib = libzfs_init()) == NULL) {
1699                 free(dataset);
1700                 return (-1);
1701         }
1702 
1703         z_fs = zfs_open(z_lib, dataset, ZFS_TYPE_DATASET);
1704         if (z_fs == NULL) {
1705                 free(dataset);
1706                 libzfs_fini(z_lib);
1707                 return (-1);
1708         }
1709 
1710         bzero(sharesmb_val, MAXPATHLEN);
1711         if (sa_zfs_sprintf_new_prop(nvl, sharesmb_val) != 0) {
1712                 free(dataset);
1713                 zfs_close(z_fs);
1714                 libzfs_fini(z_lib);
1715                 return (-1);
1716         }
1717 
1718         if (sa_zfs_sprintf_existing_prop(z_fs, sharesmb_val) != 0) {
1719                 free(dataset);
1720                 zfs_close(z_fs);
1721                 libzfs_fini(z_lib);
1722                 return (-1);
1723         }
1724 
1725         lastcomma = strrchr(sharesmb_val, ',');
1726         if ((lastcomma != NULL) && (lastcomma[1] == '\0'))
1727                 *lastcomma = '\0';
1728 
1729         (void) zfs_prop_set(z_fs, zfs_prop_to_name(ZFS_PROP_SHARESMB),
1730             sharesmb_val);
1731         free(dataset);
1732         zfs_close(z_fs);
1733         libzfs_fini(z_lib);
1734 
1735         return (0);
1736 }