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-rw-r--r--module/zfs/zfs_fuid.c704
1 files changed, 704 insertions, 0 deletions
diff --git a/module/zfs/zfs_fuid.c b/module/zfs/zfs_fuid.c
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+++ b/module/zfs/zfs_fuid.c
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+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#include <sys/zfs_context.h>
+#include <sys/sunddi.h>
+#include <sys/dmu.h>
+#include <sys/avl.h>
+#include <sys/zap.h>
+#include <sys/refcount.h>
+#include <sys/nvpair.h>
+#ifdef _KERNEL
+#include <sys/kidmap.h>
+#include <sys/sid.h>
+#include <sys/zfs_vfsops.h>
+#include <sys/zfs_znode.h>
+#endif
+#include <sys/zfs_fuid.h>
+
+/*
+ * FUID Domain table(s).
+ *
+ * The FUID table is stored as a packed nvlist of an array
+ * of nvlists which contain an index, domain string and offset
+ *
+ * During file system initialization the nvlist(s) are read and
+ * two AVL trees are created. One tree is keyed by the index number
+ * and the other by the domain string. Nodes are never removed from
+ * trees, but new entries may be added. If a new entry is added then the
+ * on-disk packed nvlist will also be updated.
+ */
+
+#define FUID_IDX "fuid_idx"
+#define FUID_DOMAIN "fuid_domain"
+#define FUID_OFFSET "fuid_offset"
+#define FUID_NVP_ARRAY "fuid_nvlist"
+
+typedef struct fuid_domain {
+ avl_node_t f_domnode;
+ avl_node_t f_idxnode;
+ ksiddomain_t *f_ksid;
+ uint64_t f_idx;
+} fuid_domain_t;
+
+static char *nulldomain = "";
+
+/*
+ * Compare two indexes.
+ */
+static int
+idx_compare(const void *arg1, const void *arg2)
+{
+ const fuid_domain_t *node1 = arg1;
+ const fuid_domain_t *node2 = arg2;
+
+ if (node1->f_idx < node2->f_idx)
+ return (-1);
+ else if (node1->f_idx > node2->f_idx)
+ return (1);
+ return (0);
+}
+
+/*
+ * Compare two domain strings.
+ */
+static int
+domain_compare(const void *arg1, const void *arg2)
+{
+ const fuid_domain_t *node1 = arg1;
+ const fuid_domain_t *node2 = arg2;
+ int val;
+
+ val = strcmp(node1->f_ksid->kd_name, node2->f_ksid->kd_name);
+ if (val == 0)
+ return (0);
+ return (val > 0 ? 1 : -1);
+}
+
+/*
+ * load initial fuid domain and idx trees. This function is used by
+ * both the kernel and zdb.
+ */
+uint64_t
+zfs_fuid_table_load(objset_t *os, uint64_t fuid_obj, avl_tree_t *idx_tree,
+ avl_tree_t *domain_tree)
+{
+ dmu_buf_t *db;
+ uint64_t fuid_size;
+
+ avl_create(idx_tree, idx_compare,
+ sizeof (fuid_domain_t), offsetof(fuid_domain_t, f_idxnode));
+ avl_create(domain_tree, domain_compare,
+ sizeof (fuid_domain_t), offsetof(fuid_domain_t, f_domnode));
+
+ VERIFY(0 == dmu_bonus_hold(os, fuid_obj, FTAG, &db));
+ fuid_size = *(uint64_t *)db->db_data;
+ dmu_buf_rele(db, FTAG);
+
+ if (fuid_size) {
+ nvlist_t **fuidnvp;
+ nvlist_t *nvp = NULL;
+ uint_t count;
+ char *packed;
+ int i;
+
+ packed = kmem_alloc(fuid_size, KM_SLEEP);
+ VERIFY(dmu_read(os, fuid_obj, 0, fuid_size, packed) == 0);
+ VERIFY(nvlist_unpack(packed, fuid_size,
+ &nvp, 0) == 0);
+ VERIFY(nvlist_lookup_nvlist_array(nvp, FUID_NVP_ARRAY,
+ &fuidnvp, &count) == 0);
+
+ for (i = 0; i != count; i++) {
+ fuid_domain_t *domnode;
+ char *domain;
+ uint64_t idx;
+
+ VERIFY(nvlist_lookup_string(fuidnvp[i], FUID_DOMAIN,
+ &domain) == 0);
+ VERIFY(nvlist_lookup_uint64(fuidnvp[i], FUID_IDX,
+ &idx) == 0);
+
+ domnode = kmem_alloc(sizeof (fuid_domain_t), KM_SLEEP);
+
+ domnode->f_idx = idx;
+ domnode->f_ksid = ksid_lookupdomain(domain);
+ avl_add(idx_tree, domnode);
+ avl_add(domain_tree, domnode);
+ }
+ nvlist_free(nvp);
+ kmem_free(packed, fuid_size);
+ }
+ return (fuid_size);
+}
+
+void
+zfs_fuid_table_destroy(avl_tree_t *idx_tree, avl_tree_t *domain_tree)
+{
+ fuid_domain_t *domnode;
+ void *cookie;
+
+ cookie = NULL;
+ while (domnode = avl_destroy_nodes(domain_tree, &cookie))
+ ksiddomain_rele(domnode->f_ksid);
+
+ avl_destroy(domain_tree);
+ cookie = NULL;
+ while (domnode = avl_destroy_nodes(idx_tree, &cookie))
+ kmem_free(domnode, sizeof (fuid_domain_t));
+ avl_destroy(idx_tree);
+}
+
+char *
+zfs_fuid_idx_domain(avl_tree_t *idx_tree, uint32_t idx)
+{
+ fuid_domain_t searchnode, *findnode;
+ avl_index_t loc;
+
+ searchnode.f_idx = idx;
+
+ findnode = avl_find(idx_tree, &searchnode, &loc);
+
+ return (findnode ? findnode->f_ksid->kd_name : nulldomain);
+}
+
+#ifdef _KERNEL
+/*
+ * Load the fuid table(s) into memory.
+ */
+static void
+zfs_fuid_init(zfsvfs_t *zfsvfs, dmu_tx_t *tx)
+{
+ int error = 0;
+
+ rw_enter(&zfsvfs->z_fuid_lock, RW_WRITER);
+
+ if (zfsvfs->z_fuid_loaded) {
+ rw_exit(&zfsvfs->z_fuid_lock);
+ return;
+ }
+
+ if (zfsvfs->z_fuid_obj == 0) {
+
+ /* first make sure we need to allocate object */
+
+ error = zap_lookup(zfsvfs->z_os, MASTER_NODE_OBJ,
+ ZFS_FUID_TABLES, 8, 1, &zfsvfs->z_fuid_obj);
+ if (error == ENOENT && tx != NULL) {
+ zfsvfs->z_fuid_obj = dmu_object_alloc(zfsvfs->z_os,
+ DMU_OT_FUID, 1 << 14, DMU_OT_FUID_SIZE,
+ sizeof (uint64_t), tx);
+ VERIFY(zap_add(zfsvfs->z_os, MASTER_NODE_OBJ,
+ ZFS_FUID_TABLES, sizeof (uint64_t), 1,
+ &zfsvfs->z_fuid_obj, tx) == 0);
+ }
+ }
+
+ if (zfsvfs->z_fuid_obj != 0) {
+ zfsvfs->z_fuid_size = zfs_fuid_table_load(zfsvfs->z_os,
+ zfsvfs->z_fuid_obj, &zfsvfs->z_fuid_idx,
+ &zfsvfs->z_fuid_domain);
+ zfsvfs->z_fuid_loaded = B_TRUE;
+ }
+
+ rw_exit(&zfsvfs->z_fuid_lock);
+}
+
+/*
+ * Query domain table for a given domain.
+ *
+ * If domain isn't found it is added to AVL trees and
+ * the results are pushed out to disk.
+ */
+int
+zfs_fuid_find_by_domain(zfsvfs_t *zfsvfs, const char *domain, char **retdomain,
+ dmu_tx_t *tx)
+{
+ fuid_domain_t searchnode, *findnode;
+ avl_index_t loc;
+ krw_t rw = RW_READER;
+
+ /*
+ * If the dummy "nobody" domain then return an index of 0
+ * to cause the created FUID to be a standard POSIX id
+ * for the user nobody.
+ */
+ if (domain[0] == '\0') {
+ *retdomain = nulldomain;
+ return (0);
+ }
+
+ searchnode.f_ksid = ksid_lookupdomain(domain);
+ if (retdomain) {
+ *retdomain = searchnode.f_ksid->kd_name;
+ }
+ if (!zfsvfs->z_fuid_loaded)
+ zfs_fuid_init(zfsvfs, tx);
+
+retry:
+ rw_enter(&zfsvfs->z_fuid_lock, rw);
+ findnode = avl_find(&zfsvfs->z_fuid_domain, &searchnode, &loc);
+
+ if (findnode) {
+ rw_exit(&zfsvfs->z_fuid_lock);
+ ksiddomain_rele(searchnode.f_ksid);
+ return (findnode->f_idx);
+ } else {
+ fuid_domain_t *domnode;
+ nvlist_t *nvp;
+ nvlist_t **fuids;
+ uint64_t retidx;
+ size_t nvsize = 0;
+ char *packed;
+ dmu_buf_t *db;
+ int i = 0;
+
+ if (rw == RW_READER && !rw_tryupgrade(&zfsvfs->z_fuid_lock)) {
+ rw_exit(&zfsvfs->z_fuid_lock);
+ rw = RW_WRITER;
+ goto retry;
+ }
+
+ domnode = kmem_alloc(sizeof (fuid_domain_t), KM_SLEEP);
+ domnode->f_ksid = searchnode.f_ksid;
+
+ retidx = domnode->f_idx = avl_numnodes(&zfsvfs->z_fuid_idx) + 1;
+
+ avl_add(&zfsvfs->z_fuid_domain, domnode);
+ avl_add(&zfsvfs->z_fuid_idx, domnode);
+ /*
+ * Now resync the on-disk nvlist.
+ */
+ VERIFY(nvlist_alloc(&nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+
+ domnode = avl_first(&zfsvfs->z_fuid_domain);
+ fuids = kmem_alloc(retidx * sizeof (void *), KM_SLEEP);
+ while (domnode) {
+ VERIFY(nvlist_alloc(&fuids[i],
+ NV_UNIQUE_NAME, KM_SLEEP) == 0);
+ VERIFY(nvlist_add_uint64(fuids[i], FUID_IDX,
+ domnode->f_idx) == 0);
+ VERIFY(nvlist_add_uint64(fuids[i],
+ FUID_OFFSET, 0) == 0);
+ VERIFY(nvlist_add_string(fuids[i++], FUID_DOMAIN,
+ domnode->f_ksid->kd_name) == 0);
+ domnode = AVL_NEXT(&zfsvfs->z_fuid_domain, domnode);
+ }
+ VERIFY(nvlist_add_nvlist_array(nvp, FUID_NVP_ARRAY,
+ fuids, retidx) == 0);
+ for (i = 0; i != retidx; i++)
+ nvlist_free(fuids[i]);
+ kmem_free(fuids, retidx * sizeof (void *));
+ VERIFY(nvlist_size(nvp, &nvsize, NV_ENCODE_XDR) == 0);
+ packed = kmem_alloc(nvsize, KM_SLEEP);
+ VERIFY(nvlist_pack(nvp, &packed, &nvsize,
+ NV_ENCODE_XDR, KM_SLEEP) == 0);
+ nvlist_free(nvp);
+ zfsvfs->z_fuid_size = nvsize;
+ dmu_write(zfsvfs->z_os, zfsvfs->z_fuid_obj, 0,
+ zfsvfs->z_fuid_size, packed, tx);
+ kmem_free(packed, zfsvfs->z_fuid_size);
+ VERIFY(0 == dmu_bonus_hold(zfsvfs->z_os, zfsvfs->z_fuid_obj,
+ FTAG, &db));
+ dmu_buf_will_dirty(db, tx);
+ *(uint64_t *)db->db_data = zfsvfs->z_fuid_size;
+ dmu_buf_rele(db, FTAG);
+
+ rw_exit(&zfsvfs->z_fuid_lock);
+ return (retidx);
+ }
+}
+
+/*
+ * Query domain table by index, returning domain string
+ *
+ * Returns a pointer from an avl node of the domain string.
+ *
+ */
+static char *
+zfs_fuid_find_by_idx(zfsvfs_t *zfsvfs, uint32_t idx)
+{
+ char *domain;
+
+ if (idx == 0 || !zfsvfs->z_use_fuids)
+ return (NULL);
+
+ if (!zfsvfs->z_fuid_loaded)
+ zfs_fuid_init(zfsvfs, NULL);
+
+ rw_enter(&zfsvfs->z_fuid_lock, RW_READER);
+
+ if (zfsvfs->z_fuid_obj)
+ domain = zfs_fuid_idx_domain(&zfsvfs->z_fuid_idx, idx);
+ else
+ domain = nulldomain;
+ rw_exit(&zfsvfs->z_fuid_lock);
+
+ ASSERT(domain);
+ return (domain);
+}
+
+void
+zfs_fuid_map_ids(znode_t *zp, cred_t *cr, uid_t *uidp, uid_t *gidp)
+{
+ *uidp = zfs_fuid_map_id(zp->z_zfsvfs, zp->z_phys->zp_uid,
+ cr, ZFS_OWNER);
+ *gidp = zfs_fuid_map_id(zp->z_zfsvfs, zp->z_phys->zp_gid,
+ cr, ZFS_GROUP);
+}
+
+uid_t
+zfs_fuid_map_id(zfsvfs_t *zfsvfs, uint64_t fuid,
+ cred_t *cr, zfs_fuid_type_t type)
+{
+ uint32_t index = FUID_INDEX(fuid);
+ char *domain;
+ uid_t id;
+
+ if (index == 0)
+ return (fuid);
+
+ domain = zfs_fuid_find_by_idx(zfsvfs, index);
+ ASSERT(domain != NULL);
+
+ if (type == ZFS_OWNER || type == ZFS_ACE_USER) {
+ (void) kidmap_getuidbysid(crgetzone(cr), domain,
+ FUID_RID(fuid), &id);
+ } else {
+ (void) kidmap_getgidbysid(crgetzone(cr), domain,
+ FUID_RID(fuid), &id);
+ }
+ return (id);
+}
+
+/*
+ * Add a FUID node to the list of fuid's being created for this
+ * ACL
+ *
+ * If ACL has multiple domains, then keep only one copy of each unique
+ * domain.
+ */
+static void
+zfs_fuid_node_add(zfs_fuid_info_t **fuidpp, const char *domain, uint32_t rid,
+ uint64_t idx, uint64_t id, zfs_fuid_type_t type)
+{
+ zfs_fuid_t *fuid;
+ zfs_fuid_domain_t *fuid_domain;
+ zfs_fuid_info_t *fuidp;
+ uint64_t fuididx;
+ boolean_t found = B_FALSE;
+
+ if (*fuidpp == NULL)
+ *fuidpp = zfs_fuid_info_alloc();
+
+ fuidp = *fuidpp;
+ /*
+ * First find fuid domain index in linked list
+ *
+ * If one isn't found then create an entry.
+ */
+
+ for (fuididx = 1, fuid_domain = list_head(&fuidp->z_domains);
+ fuid_domain; fuid_domain = list_next(&fuidp->z_domains,
+ fuid_domain), fuididx++) {
+ if (idx == fuid_domain->z_domidx) {
+ found = B_TRUE;
+ break;
+ }
+ }
+
+ if (!found) {
+ fuid_domain = kmem_alloc(sizeof (zfs_fuid_domain_t), KM_SLEEP);
+ fuid_domain->z_domain = domain;
+ fuid_domain->z_domidx = idx;
+ list_insert_tail(&fuidp->z_domains, fuid_domain);
+ fuidp->z_domain_str_sz += strlen(domain) + 1;
+ fuidp->z_domain_cnt++;
+ }
+
+ if (type == ZFS_ACE_USER || type == ZFS_ACE_GROUP) {
+ /*
+ * Now allocate fuid entry and add it on the end of the list
+ */
+
+ fuid = kmem_alloc(sizeof (zfs_fuid_t), KM_SLEEP);
+ fuid->z_id = id;
+ fuid->z_domidx = idx;
+ fuid->z_logfuid = FUID_ENCODE(fuididx, rid);
+
+ list_insert_tail(&fuidp->z_fuids, fuid);
+ fuidp->z_fuid_cnt++;
+ } else {
+ if (type == ZFS_OWNER)
+ fuidp->z_fuid_owner = FUID_ENCODE(fuididx, rid);
+ else
+ fuidp->z_fuid_group = FUID_ENCODE(fuididx, rid);
+ }
+}
+
+/*
+ * Create a file system FUID, based on information in the users cred
+ */
+uint64_t
+zfs_fuid_create_cred(zfsvfs_t *zfsvfs, zfs_fuid_type_t type,
+ dmu_tx_t *tx, cred_t *cr, zfs_fuid_info_t **fuidp)
+{
+ uint64_t idx;
+ ksid_t *ksid;
+ uint32_t rid;
+ char *kdomain;
+ const char *domain;
+ uid_t id;
+
+ VERIFY(type == ZFS_OWNER || type == ZFS_GROUP);
+
+ ksid = crgetsid(cr, (type == ZFS_OWNER) ? KSID_OWNER : KSID_GROUP);
+ if (ksid) {
+ id = ksid_getid(ksid);
+ } else {
+ if (type == ZFS_OWNER)
+ id = crgetuid(cr);
+ else
+ id = crgetgid(cr);
+ }
+
+ if (!zfsvfs->z_use_fuids || (!IS_EPHEMERAL(id)))
+ return ((uint64_t)id);
+
+ rid = ksid_getrid(ksid);
+ domain = ksid_getdomain(ksid);
+
+ idx = zfs_fuid_find_by_domain(zfsvfs, domain, &kdomain, tx);
+
+ zfs_fuid_node_add(fuidp, kdomain, rid, idx, id, type);
+
+ return (FUID_ENCODE(idx, rid));
+}
+
+/*
+ * Create a file system FUID for an ACL ace
+ * or a chown/chgrp of the file.
+ * This is similar to zfs_fuid_create_cred, except that
+ * we can't find the domain + rid information in the
+ * cred. Instead we have to query Winchester for the
+ * domain and rid.
+ *
+ * During replay operations the domain+rid information is
+ * found in the zfs_fuid_info_t that the replay code has
+ * attached to the zfsvfs of the file system.
+ */
+uint64_t
+zfs_fuid_create(zfsvfs_t *zfsvfs, uint64_t id, cred_t *cr,
+ zfs_fuid_type_t type, dmu_tx_t *tx, zfs_fuid_info_t **fuidpp)
+{
+ const char *domain;
+ char *kdomain;
+ uint32_t fuid_idx = FUID_INDEX(id);
+ uint32_t rid;
+ idmap_stat status;
+ uint64_t idx;
+ boolean_t is_replay = (zfsvfs->z_assign >= TXG_INITIAL);
+ zfs_fuid_t *zfuid = NULL;
+ zfs_fuid_info_t *fuidp;
+
+ /*
+ * If POSIX ID, or entry is already a FUID then
+ * just return the id
+ *
+ * We may also be handed an already FUID'ized id via
+ * chmod.
+ */
+
+ if (!zfsvfs->z_use_fuids || !IS_EPHEMERAL(id) || fuid_idx != 0)
+ return (id);
+
+ if (is_replay) {
+ fuidp = zfsvfs->z_fuid_replay;
+
+ /*
+ * If we are passed an ephemeral id, but no
+ * fuid_info was logged then return NOBODY.
+ * This is most likely a result of idmap service
+ * not being available.
+ */
+ if (fuidp == NULL)
+ return (UID_NOBODY);
+
+ switch (type) {
+ case ZFS_ACE_USER:
+ case ZFS_ACE_GROUP:
+ zfuid = list_head(&fuidp->z_fuids);
+ rid = FUID_RID(zfuid->z_logfuid);
+ idx = FUID_INDEX(zfuid->z_logfuid);
+ break;
+ case ZFS_OWNER:
+ rid = FUID_RID(fuidp->z_fuid_owner);
+ idx = FUID_INDEX(fuidp->z_fuid_owner);
+ break;
+ case ZFS_GROUP:
+ rid = FUID_RID(fuidp->z_fuid_group);
+ idx = FUID_INDEX(fuidp->z_fuid_group);
+ break;
+ };
+ domain = fuidp->z_domain_table[idx -1];
+ } else {
+ if (type == ZFS_OWNER || type == ZFS_ACE_USER)
+ status = kidmap_getsidbyuid(crgetzone(cr), id,
+ &domain, &rid);
+ else
+ status = kidmap_getsidbygid(crgetzone(cr), id,
+ &domain, &rid);
+
+ if (status != 0) {
+ /*
+ * When returning nobody we will need to
+ * make a dummy fuid table entry for logging
+ * purposes.
+ */
+ rid = UID_NOBODY;
+ domain = nulldomain;
+ }
+ }
+
+ idx = zfs_fuid_find_by_domain(zfsvfs, domain, &kdomain, tx);
+
+ if (!is_replay)
+ zfs_fuid_node_add(fuidpp, kdomain, rid, idx, id, type);
+ else if (zfuid != NULL) {
+ list_remove(&fuidp->z_fuids, zfuid);
+ kmem_free(zfuid, sizeof (zfs_fuid_t));
+ }
+ return (FUID_ENCODE(idx, rid));
+}
+
+void
+zfs_fuid_destroy(zfsvfs_t *zfsvfs)
+{
+ rw_enter(&zfsvfs->z_fuid_lock, RW_WRITER);
+ if (!zfsvfs->z_fuid_loaded) {
+ rw_exit(&zfsvfs->z_fuid_lock);
+ return;
+ }
+ zfs_fuid_table_destroy(&zfsvfs->z_fuid_idx, &zfsvfs->z_fuid_domain);
+ rw_exit(&zfsvfs->z_fuid_lock);
+}
+
+/*
+ * Allocate zfs_fuid_info for tracking FUIDs created during
+ * zfs_mknode, VOP_SETATTR() or VOP_SETSECATTR()
+ */
+zfs_fuid_info_t *
+zfs_fuid_info_alloc(void)
+{
+ zfs_fuid_info_t *fuidp;
+
+ fuidp = kmem_zalloc(sizeof (zfs_fuid_info_t), KM_SLEEP);
+ list_create(&fuidp->z_domains, sizeof (zfs_fuid_domain_t),
+ offsetof(zfs_fuid_domain_t, z_next));
+ list_create(&fuidp->z_fuids, sizeof (zfs_fuid_t),
+ offsetof(zfs_fuid_t, z_next));
+ return (fuidp);
+}
+
+/*
+ * Release all memory associated with zfs_fuid_info_t
+ */
+void
+zfs_fuid_info_free(zfs_fuid_info_t *fuidp)
+{
+ zfs_fuid_t *zfuid;
+ zfs_fuid_domain_t *zdomain;
+
+ while ((zfuid = list_head(&fuidp->z_fuids)) != NULL) {
+ list_remove(&fuidp->z_fuids, zfuid);
+ kmem_free(zfuid, sizeof (zfs_fuid_t));
+ }
+
+ if (fuidp->z_domain_table != NULL)
+ kmem_free(fuidp->z_domain_table,
+ (sizeof (char **)) * fuidp->z_domain_cnt);
+
+ while ((zdomain = list_head(&fuidp->z_domains)) != NULL) {
+ list_remove(&fuidp->z_domains, zdomain);
+ kmem_free(zdomain, sizeof (zfs_fuid_domain_t));
+ }
+
+ kmem_free(fuidp, sizeof (zfs_fuid_info_t));
+}
+
+/*
+ * Check to see if id is a groupmember. If cred
+ * has ksid info then sidlist is checked first
+ * and if still not found then POSIX groups are checked
+ *
+ * Will use a straight FUID compare when possible.
+ */
+boolean_t
+zfs_groupmember(zfsvfs_t *zfsvfs, uint64_t id, cred_t *cr)
+{
+ ksid_t *ksid = crgetsid(cr, KSID_GROUP);
+ uid_t gid;
+
+ if (ksid) {
+ int i;
+ ksid_t *ksid_groups;
+ ksidlist_t *ksidlist = crgetsidlist(cr);
+ uint32_t idx = FUID_INDEX(id);
+ uint32_t rid = FUID_RID(id);
+
+ ASSERT(ksidlist);
+ ksid_groups = ksidlist->ksl_sids;
+
+ for (i = 0; i != ksidlist->ksl_nsid; i++) {
+ if (idx == 0) {
+ if (id != IDMAP_WK_CREATOR_GROUP_GID &&
+ id == ksid_groups[i].ks_id) {
+ return (B_TRUE);
+ }
+ } else {
+ char *domain;
+
+ domain = zfs_fuid_find_by_idx(zfsvfs, idx);
+ ASSERT(domain != NULL);
+
+ if (strcmp(domain,
+ IDMAP_WK_CREATOR_SID_AUTHORITY) == 0)
+ return (B_FALSE);
+
+ if ((strcmp(domain,
+ ksid_groups[i].ks_domain->kd_name) == 0) &&
+ rid == ksid_groups[i].ks_rid)
+ return (B_TRUE);
+ }
+ }
+ }
+
+ /*
+ * Not found in ksidlist, check posix groups
+ */
+ gid = zfs_fuid_map_id(zfsvfs, id, cr, ZFS_GROUP);
+ return (groupmember(gid, cr));
+}
+#endif