/* * Copyright (c) 2007 Pawel Jakub Dawidek * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static MALLOC_DEFINE(M_ZONES, "zones_data", "Zones data"); /* * Structure to record list of ZFS datasets exported to a zone. */ typedef struct zone_dataset { LIST_ENTRY(zone_dataset) zd_next; char zd_dataset[0]; } zone_dataset_t; LIST_HEAD(zone_dataset_head, zone_dataset); static int zone_slot; int zone_dataset_attach(struct ucred *cred, const char *dataset, int jailid) { struct zone_dataset_head *head; zone_dataset_t *zd, *zd2; struct prison *pr; int dofree, error; if ((error = priv_check_cred(cred, PRIV_ZFS_JAIL)) != 0) return (error); /* Allocate memory before we grab prison's mutex. */ zd = malloc(sizeof (*zd) + strlen(dataset) + 1, M_ZONES, M_WAITOK); sx_slock(&allprison_lock); pr = prison_find(jailid); /* Locks &pr->pr_mtx. */ sx_sunlock(&allprison_lock); if (pr == NULL) { free(zd, M_ZONES); return (ENOENT); } head = osd_jail_get(pr, zone_slot); if (head != NULL) { dofree = 0; LIST_FOREACH(zd2, head, zd_next) { if (strcmp(dataset, zd2->zd_dataset) == 0) { free(zd, M_ZONES); error = EEXIST; goto end; } } } else { dofree = 1; prison_hold_locked(pr); mtx_unlock(&pr->pr_mtx); head = malloc(sizeof (*head), M_ZONES, M_WAITOK); LIST_INIT(head); mtx_lock(&pr->pr_mtx); error = osd_jail_set(pr, zone_slot, head); KASSERT(error == 0, ("osd_jail_set() failed (error=%d)", error)); } strcpy(zd->zd_dataset, dataset); LIST_INSERT_HEAD(head, zd, zd_next); end: if (dofree) prison_free_locked(pr); else mtx_unlock(&pr->pr_mtx); return (error); } int zone_dataset_detach(struct ucred *cred, const char *dataset, int jailid) { struct zone_dataset_head *head; zone_dataset_t *zd; struct prison *pr; int error; if ((error = priv_check_cred(cred, PRIV_ZFS_JAIL)) != 0) return (error); sx_slock(&allprison_lock); pr = prison_find(jailid); sx_sunlock(&allprison_lock); if (pr == NULL) return (ENOENT); head = osd_jail_get(pr, zone_slot); if (head == NULL) { error = ENOENT; goto end; } LIST_FOREACH(zd, head, zd_next) { if (strcmp(dataset, zd->zd_dataset) == 0) break; } if (zd == NULL) error = ENOENT; else { LIST_REMOVE(zd, zd_next); free(zd, M_ZONES); if (LIST_EMPTY(head)) osd_jail_del(pr, zone_slot); error = 0; } end: mtx_unlock(&pr->pr_mtx); return (error); } /* * Returns true if the named dataset is visible in the current zone. * The 'write' parameter is set to 1 if the dataset is also writable. */ int zone_dataset_visible(const char *dataset, int *write) { struct zone_dataset_head *head; zone_dataset_t *zd; struct prison *pr; size_t len; int ret = 0; if (dataset[0] == '\0') return (0); if (INGLOBALZONE(curproc)) { if (write != NULL) *write = 1; return (1); } pr = curthread->td_ucred->cr_prison; mtx_lock(&pr->pr_mtx); head = osd_jail_get(pr, zone_slot); if (head == NULL) goto end; /* * Walk the list once, looking for datasets which match exactly, or * specify a dataset underneath an exported dataset. If found, return * true and note that it is writable. */ LIST_FOREACH(zd, head, zd_next) { len = strlen(zd->zd_dataset); if (strlen(dataset) >= len && memcmp(dataset, zd->zd_dataset, len) == 0 && (dataset[len] == '\0' || dataset[len] == '/' || dataset[len] == '@')) { if (write) *write = 1; ret = 1; goto end; } } /* * Walk the list a second time, searching for datasets which are parents * of exported datasets. These should be visible, but read-only. * * Note that we also have to support forms such as 'pool/dataset/', with * a trailing slash. */ LIST_FOREACH(zd, head, zd_next) { len = strlen(dataset); if (dataset[len - 1] == '/') len--; /* Ignore trailing slash */ if (len < strlen(zd->zd_dataset) && memcmp(dataset, zd->zd_dataset, len) == 0 && zd->zd_dataset[len] == '/') { if (write) *write = 0; ret = 1; goto end; } } end: mtx_unlock(&pr->pr_mtx); return (ret); } static void zone_destroy(void *arg) { struct zone_dataset_head *head; zone_dataset_t *zd; head = arg; while ((zd = LIST_FIRST(head)) != NULL) { LIST_REMOVE(zd, zd_next); free(zd, M_ZONES); } free(head, M_ZONES); } uint32_t zone_get_hostid(void *ptr) { KASSERT(ptr == NULL, ("only NULL pointer supported in %s", __func__)); return ((uint32_t)curthread->td_ucred->cr_prison->pr_hostid); } static void zone_sysinit(void *arg __unused) { zone_slot = osd_jail_register(zone_destroy, NULL); } static void zone_sysuninit(void *arg __unused) { osd_jail_deregister(zone_slot); } SYSINIT(zone_sysinit, SI_SUB_DRIVERS, SI_ORDER_ANY, zone_sysinit, NULL); SYSUNINIT(zone_sysuninit, SI_SUB_DRIVERS, SI_ORDER_ANY, zone_sysuninit, NULL);