/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2017 Kyle J. Kneitinger * * 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 REGENTS 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 REGENTS 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 __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "be.h" #include "be_impl.h" struct promote_entry { char name[BE_MAXPATHLEN]; SLIST_ENTRY(promote_entry) link; }; struct be_destroy_data { libbe_handle_t *lbh; char target_name[BE_MAXPATHLEN]; char *snapname; SLIST_HEAD(, promote_entry) promotelist; }; #if SOON static int be_create_child_noent(libbe_handle_t *lbh, const char *active, const char *child_path); static int be_create_child_cloned(libbe_handle_t *lbh, const char *active); #endif /* Arbitrary... should tune */ #define BE_SNAP_SERIAL_MAX 1024 /* * Iterator function for locating the rootfs amongst the children of the * zfs_be_root set by loader(8). data is expected to be a libbe_handle_t *. */ static int be_locate_rootfs(libbe_handle_t *lbh) { struct statfs sfs; struct mnttab entry; zfs_handle_t *zfs; /* * Check first if root is ZFS; if not, we'll bail on rootfs capture. * Unfortunately needed because zfs_path_to_zhandle will emit to * stderr if / isn't actually a ZFS filesystem, which we'd like * to avoid. */ if (statfs("/", &sfs) == 0) { statfs2mnttab(&sfs, &entry); if (strcmp(entry.mnt_fstype, MNTTYPE_ZFS) != 0) return (1); } else return (1); zfs = zfs_path_to_zhandle(lbh->lzh, "/", ZFS_TYPE_FILESYSTEM); if (zfs == NULL) return (1); strlcpy(lbh->rootfs, zfs_get_name(zfs), sizeof(lbh->rootfs)); zfs_close(zfs); return (0); } /* * Initializes the libbe context to operate in the root boot environment * dataset, for example, zroot/ROOT. */ libbe_handle_t * libbe_init(const char *root) { char altroot[MAXPATHLEN]; libbe_handle_t *lbh; char *poolname, *pos; int pnamelen; lbh = NULL; poolname = pos = NULL; if ((lbh = calloc(1, sizeof(libbe_handle_t))) == NULL) goto err; if ((lbh->lzh = libzfs_init()) == NULL) goto err; /* * Grab rootfs, we'll work backwards from there if an optional BE root * has not been passed in. */ if (be_locate_rootfs(lbh) != 0) { if (root == NULL) goto err; *lbh->rootfs = '\0'; } if (root == NULL) { /* Strip off the final slash from rootfs to get the be root */ strlcpy(lbh->root, lbh->rootfs, sizeof(lbh->root)); pos = strrchr(lbh->root, '/'); if (pos == NULL) goto err; *pos = '\0'; } else strlcpy(lbh->root, root, sizeof(lbh->root)); if ((pos = strchr(lbh->root, '/')) == NULL) goto err; pnamelen = pos - lbh->root; poolname = malloc(pnamelen + 1); if (poolname == NULL) goto err; strlcpy(poolname, lbh->root, pnamelen + 1); if ((lbh->active_phandle = zpool_open(lbh->lzh, poolname)) == NULL) goto err; free(poolname); poolname = NULL; if (zpool_get_prop(lbh->active_phandle, ZPOOL_PROP_BOOTFS, lbh->bootfs, sizeof(lbh->bootfs), NULL, true) != 0) goto err; if (zpool_get_prop(lbh->active_phandle, ZPOOL_PROP_ALTROOT, altroot, sizeof(altroot), NULL, true) == 0 && strcmp(altroot, "-") != 0) lbh->altroot_len = strlen(altroot); return (lbh); err: if (lbh != NULL) { if (lbh->active_phandle != NULL) zpool_close(lbh->active_phandle); if (lbh->lzh != NULL) libzfs_fini(lbh->lzh); free(lbh); } free(poolname); return (NULL); } /* * Free memory allocated by libbe_init() */ void libbe_close(libbe_handle_t *lbh) { if (lbh->active_phandle != NULL) zpool_close(lbh->active_phandle); libzfs_fini(lbh->lzh); free(lbh); } /* * Proxy through to libzfs for the moment. */ void be_nicenum(uint64_t num, char *buf, size_t buflen) { zfs_nicenum(num, buf, buflen); } static bool be_should_promote_clones(zfs_handle_t *zfs_hdl, struct be_destroy_data *bdd) { char *atpos; if (zfs_get_type(zfs_hdl) != ZFS_TYPE_SNAPSHOT) return (false); /* * If we're deleting a snapshot, we need to make sure we only promote * clones that are derived from one of the snapshots we're deleting, * rather than that of a snapshot we're not touching. This keeps stuff * in a consistent state, making sure that we don't error out unless * we really need to. */ if (bdd->snapname == NULL) return (true); atpos = strchr(zfs_get_name(zfs_hdl), '@'); return (strcmp(atpos + 1, bdd->snapname) == 0); } /* * This is executed from be_promote_dependent_clones via zfs_iter_dependents, * It checks if the dependent type is a snapshot then attempts to find any * clones associated with it. Any clones not related to the destroy target are * added to the promote list. */ static int be_dependent_clone_cb(zfs_handle_t *zfs_hdl, void *data) { int err; bool found; char *name; struct nvlist *nvl; struct nvpair *nvp; struct be_destroy_data *bdd; struct promote_entry *entry, *newentry; nvp = NULL; err = 0; bdd = (struct be_destroy_data *)data; if (be_should_promote_clones(zfs_hdl, bdd) && (nvl = zfs_get_clones_nvl(zfs_hdl)) != NULL) { while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) { name = nvpair_name(nvp); /* * Skip if the clone is equal to, or a child of, the * destroy target. */ if (strncmp(name, bdd->target_name, strlen(bdd->target_name)) == 0 || strstr(name, bdd->target_name) == name) { continue; } found = false; SLIST_FOREACH(entry, &bdd->promotelist, link) { if (strcmp(entry->name, name) == 0) { found = true; break; } } if (found) continue; newentry = malloc(sizeof(struct promote_entry)); if (newentry == NULL) { err = ENOMEM; break; } #define BE_COPY_NAME(entry, src) \ strlcpy((entry)->name, (src), sizeof((entry)->name)) if (BE_COPY_NAME(newentry, name) >= sizeof(newentry->name)) { /* Shouldn't happen. */ free(newentry); err = ENAMETOOLONG; break; } #undef BE_COPY_NAME /* * We're building up a SLIST here to make sure both that * we get the order right and so that we don't * inadvertently observe the wrong state by promoting * datasets while we're still walking the tree. The * latter can lead to situations where we promote a BE * then effectively demote it again. */ SLIST_INSERT_HEAD(&bdd->promotelist, newentry, link); } nvlist_free(nvl); } zfs_close(zfs_hdl); return (err); } /* * This is called before a destroy, so that any datasets(environments) that are * dependent on this one get promoted before destroying the target. */ static int be_promote_dependent_clones(zfs_handle_t *zfs_hdl, struct be_destroy_data *bdd) { int err; zfs_handle_t *clone; struct promote_entry *entry; snprintf(bdd->target_name, BE_MAXPATHLEN, "%s/", zfs_get_name(zfs_hdl)); err = zfs_iter_dependents(zfs_hdl, 0, true, be_dependent_clone_cb, bdd); /* * Drain the list and walk away from it if we're only deleting a * snapshot. */ if (bdd->snapname != NULL && !SLIST_EMPTY(&bdd->promotelist)) err = BE_ERR_HASCLONES; while (!SLIST_EMPTY(&bdd->promotelist)) { entry = SLIST_FIRST(&bdd->promotelist); SLIST_REMOVE_HEAD(&bdd->promotelist, link); #define ZFS_GRAB_CLONE() \ zfs_open(bdd->lbh->lzh, entry->name, ZFS_TYPE_FILESYSTEM) /* * Just skip this part on error, we still want to clean up the * promotion list after the first error. We'll then preserve it * all the way back. */ if (err == 0 && (clone = ZFS_GRAB_CLONE()) != NULL) { err = zfs_promote(clone); if (err != 0) err = BE_ERR_DESTROYMNT; zfs_close(clone); } #undef ZFS_GRAB_CLONE free(entry); } return (err); } static int be_destroy_cb(zfs_handle_t *zfs_hdl, void *data) { char path[BE_MAXPATHLEN]; struct be_destroy_data *bdd; zfs_handle_t *snap; int err; bdd = (struct be_destroy_data *)data; if (bdd->snapname == NULL) { err = zfs_iter_children(zfs_hdl, 0, be_destroy_cb, data); if (err != 0) return (err); return (zfs_destroy(zfs_hdl, false)); } /* If we're dealing with snapshots instead, delete that one alone */ err = zfs_iter_filesystems(zfs_hdl, 0, be_destroy_cb, data); if (err != 0) return (err); /* * This part is intentionally glossing over any potential errors, * because there's a lot less potential for errors when we're cleaning * up snapshots rather than a full deep BE. The primary error case * here being if the snapshot doesn't exist in the first place, which * the caller will likely deem insignificant as long as it doesn't * exist after the call. Thus, such a missing snapshot shouldn't jam * up the destruction. */ snprintf(path, sizeof(path), "%s@%s", zfs_get_name(zfs_hdl), bdd->snapname); if (!zfs_dataset_exists(bdd->lbh->lzh, path, ZFS_TYPE_SNAPSHOT)) return (0); snap = zfs_open(bdd->lbh->lzh, path, ZFS_TYPE_SNAPSHOT); if (snap != NULL) zfs_destroy(snap, false); return (0); } #define BE_DESTROY_WANTORIGIN (BE_DESTROY_ORIGIN | BE_DESTROY_AUTOORIGIN) /* * Destroy the boot environment or snapshot specified by the name * parameter. Options are or'd together with the possible values: * BE_DESTROY_FORCE : forces operation on mounted datasets * BE_DESTROY_ORIGIN: destroy the origin snapshot as well */ static int be_destroy_internal(libbe_handle_t *lbh, const char *name, int options, bool odestroyer) { struct be_destroy_data bdd; char origin[BE_MAXPATHLEN], path[BE_MAXPATHLEN]; zfs_handle_t *fs; char *snapdelim; int err, force, mounted; size_t rootlen; bdd.lbh = lbh; bdd.snapname = NULL; SLIST_INIT(&bdd.promotelist); force = options & BE_DESTROY_FORCE; *origin = '\0'; be_root_concat(lbh, name, path); if ((snapdelim = strchr(path, '@')) == NULL) { if (!zfs_dataset_exists(lbh->lzh, path, ZFS_TYPE_FILESYSTEM)) return (set_error(lbh, BE_ERR_NOENT)); if (strcmp(path, lbh->rootfs) == 0 || strcmp(path, lbh->bootfs) == 0) return (set_error(lbh, BE_ERR_DESTROYACT)); fs = zfs_open(lbh->lzh, path, ZFS_TYPE_FILESYSTEM); if (fs == NULL) return (set_error(lbh, BE_ERR_ZFSOPEN)); /* Don't destroy a mounted dataset unless force is specified */ if ((mounted = zfs_is_mounted(fs, NULL)) != 0) { if (force) { zfs_unmount(fs, NULL, 0); } else { free(bdd.snapname); return (set_error(lbh, BE_ERR_DESTROYMNT)); } } } else { /* * If we're initially destroying a snapshot, origin options do * not make sense. If we're destroying the origin snapshot of * a BE, we want to maintain the options in case we need to * fake success after failing to promote. */ if (!odestroyer) options &= ~BE_DESTROY_WANTORIGIN; if (!zfs_dataset_exists(lbh->lzh, path, ZFS_TYPE_SNAPSHOT)) return (set_error(lbh, BE_ERR_NOENT)); bdd.snapname = strdup(snapdelim + 1); if (bdd.snapname == NULL) return (set_error(lbh, BE_ERR_NOMEM)); *snapdelim = '\0'; fs = zfs_open(lbh->lzh, path, ZFS_TYPE_DATASET); if (fs == NULL) { free(bdd.snapname); return (set_error(lbh, BE_ERR_ZFSOPEN)); } } /* * Whether we're destroying a BE or a single snapshot, we need to walk * the tree of what we're going to destroy and promote everything in our * path so that we can make it happen. */ if ((err = be_promote_dependent_clones(fs, &bdd)) != 0) { free(bdd.snapname); /* * If we're just destroying the origin of some other dataset * we were invoked to destroy, then we just ignore * BE_ERR_HASCLONES and return success unless the caller wanted * to force the issue. */ if (odestroyer && err == BE_ERR_HASCLONES && (options & BE_DESTROY_AUTOORIGIN) != 0) return (0); return (set_error(lbh, err)); } /* * This was deferred until after we promote all of the derivatives so * that we grab the new origin after everything's settled down. */ if ((options & BE_DESTROY_WANTORIGIN) != 0 && zfs_prop_get(fs, ZFS_PROP_ORIGIN, origin, sizeof(origin), NULL, NULL, 0, 1) != 0 && (options & BE_DESTROY_ORIGIN) != 0) return (set_error(lbh, BE_ERR_NOORIGIN)); /* * If the caller wants auto-origin destruction and the origin * name matches one of our automatically created snapshot names * (i.e. strftime("%F-%T") with a serial at the end), then * we'll set the DESTROY_ORIGIN flag and nuke it * be_is_auto_snapshot_name is exported from libbe(3) so that * the caller can determine if it needs to warn about the origin * not being destroyed or not. */ if ((options & BE_DESTROY_AUTOORIGIN) != 0 && *origin != '\0' && be_is_auto_snapshot_name(lbh, origin)) options |= BE_DESTROY_ORIGIN; err = be_destroy_cb(fs, &bdd); zfs_close(fs); free(bdd.snapname); if (err != 0) { /* Children are still present or the mount is referenced */ if (err == EBUSY) return (set_error(lbh, BE_ERR_DESTROYMNT)); return (set_error(lbh, BE_ERR_UNKNOWN)); } if ((options & BE_DESTROY_ORIGIN) == 0) return (0); /* The origin can't possibly be shorter than the BE root */ rootlen = strlen(lbh->root); if (*origin == '\0' || strlen(origin) <= rootlen + 1) return (set_error(lbh, BE_ERR_INVORIGIN)); /* * We'll be chopping off the BE root and running this back through * be_destroy, so that we properly handle the origin snapshot whether * it be that of a deep BE or not. */ if (strncmp(origin, lbh->root, rootlen) != 0 || origin[rootlen] != '/') return (0); return (be_destroy_internal(lbh, origin + rootlen + 1, options & ~BE_DESTROY_ORIGIN, true)); } int be_destroy(libbe_handle_t *lbh, const char *name, int options) { /* * The consumer must not set both BE_DESTROY_AUTOORIGIN and * BE_DESTROY_ORIGIN. Internally, we'll set the latter from the former. * The latter should imply that we must succeed at destroying the * origin, or complain otherwise. */ if ((options & BE_DESTROY_WANTORIGIN) == BE_DESTROY_WANTORIGIN) return (set_error(lbh, BE_ERR_UNKNOWN)); return (be_destroy_internal(lbh, name, options, false)); } static void be_setup_snapshot_name(libbe_handle_t *lbh, char *buf, size_t buflen) { time_t rawtime; int len, serial; time(&rawtime); len = strlen(buf); len += strftime(buf + len, buflen - len, "@%F-%T", localtime(&rawtime)); /* No room for serial... caller will do its best */ if (buflen - len < 2) return; for (serial = 0; serial < BE_SNAP_SERIAL_MAX; ++serial) { snprintf(buf + len, buflen - len, "-%d", serial); if (!zfs_dataset_exists(lbh->lzh, buf, ZFS_TYPE_SNAPSHOT)) return; } } bool be_is_auto_snapshot_name(libbe_handle_t *lbh __unused, const char *name) { const char *snap; int day, hour, minute, month, second, serial, year; if ((snap = strchr(name, '@')) == NULL) return (false); ++snap; /* We'll grab the individual components and do some light validation. */ if (sscanf(snap, "%d-%d-%d-%d:%d:%d-%d", &year, &month, &day, &hour, &minute, &second, &serial) != 7) return (false); return (year >= 1970) && (month >= 1 && month <= 12) && (day >= 1 && day <= 31) && (hour >= 0 && hour <= 23) && (minute >= 0 && minute <= 59) && (second >= 0 && second <= 60) && serial >= 0; } int be_snapshot(libbe_handle_t *lbh, const char *source, const char *snap_name, bool recursive, char *result) { char buf[BE_MAXPATHLEN]; int err; be_root_concat(lbh, source, buf); if ((err = be_exists(lbh, buf)) != 0) return (set_error(lbh, err)); if (snap_name != NULL) { if (strlcat(buf, "@", sizeof(buf)) >= sizeof(buf)) return (set_error(lbh, BE_ERR_INVALIDNAME)); if (strlcat(buf, snap_name, sizeof(buf)) >= sizeof(buf)) return (set_error(lbh, BE_ERR_INVALIDNAME)); if (result != NULL) snprintf(result, BE_MAXPATHLEN, "%s@%s", source, snap_name); } else { be_setup_snapshot_name(lbh, buf, sizeof(buf)); if (result != NULL && strlcpy(result, strrchr(buf, '/') + 1, sizeof(buf)) >= sizeof(buf)) return (set_error(lbh, BE_ERR_INVALIDNAME)); } if ((err = zfs_snapshot(lbh->lzh, buf, recursive, NULL)) != 0) { switch (err) { case EZFS_INVALIDNAME: return (set_error(lbh, BE_ERR_INVALIDNAME)); default: /* * The other errors that zfs_ioc_snapshot might return * shouldn't happen if we've set things up properly, so * we'll gloss over them and call it UNKNOWN as it will * require further triage. */ if (errno == ENOTSUP) return (set_error(lbh, BE_ERR_NOPOOL)); return (set_error(lbh, BE_ERR_UNKNOWN)); } } return (BE_ERR_SUCCESS); } /* * Create the boot environment specified by the name parameter */ int be_create(libbe_handle_t *lbh, const char *name) { int err; err = be_create_from_existing(lbh, name, be_active_path(lbh)); return (set_error(lbh, err)); } static int be_deep_clone_prop(int prop, void *cb) { int err; struct libbe_dccb *dccb; zprop_source_t src; char pval[BE_MAXPATHLEN]; char source[BE_MAXPATHLEN]; char *val; dccb = cb; /* Skip some properties we don't want to touch */ if (prop == ZFS_PROP_CANMOUNT) return (ZPROP_CONT); /* Don't copy readonly properties */ if (zfs_prop_readonly(prop)) return (ZPROP_CONT); if ((err = zfs_prop_get(dccb->zhp, prop, (char *)&pval, sizeof(pval), &src, (char *)&source, sizeof(source), false))) /* Just continue if we fail to read a property */ return (ZPROP_CONT); /* * Only copy locally defined or received properties. This continues * to avoid temporary/default/local properties intentionally without * breaking received datasets. */ if (src != ZPROP_SRC_LOCAL && src != ZPROP_SRC_RECEIVED) return (ZPROP_CONT); /* Augment mountpoint with altroot, if needed */ val = pval; if (prop == ZFS_PROP_MOUNTPOINT) val = be_mountpoint_augmented(dccb->lbh, val); nvlist_add_string(dccb->props, zfs_prop_to_name(prop), val); return (ZPROP_CONT); } /* * Return the corresponding boot environment path for a given * dataset path, the constructed path is placed in 'result'. * * example: say our new boot environment name is 'bootenv' and * the dataset path is 'zroot/ROOT/default/data/set'. * * result should produce: 'zroot/ROOT/bootenv/data/set' */ static int be_get_path(struct libbe_deep_clone *ldc, const char *dspath, char *result, int result_size) { char *pos; char *child_dataset; /* match the root path for the boot environments */ pos = strstr(dspath, ldc->lbh->root); /* no match, different pools? */ if (pos == NULL) return (BE_ERR_BADPATH); /* root path of the new boot environment */ snprintf(result, result_size, "%s/%s", ldc->lbh->root, ldc->bename); /* gets us to the parent dataset, the +1 consumes a trailing slash */ pos += strlen(ldc->lbh->root) + 1; /* skip the parent dataset */ if ((child_dataset = strchr(pos, '/')) != NULL) strlcat(result, child_dataset, result_size); return (BE_ERR_SUCCESS); } static int be_clone_cb(zfs_handle_t *ds, void *data) { int err; char be_path[BE_MAXPATHLEN]; char snap_path[BE_MAXPATHLEN]; const char *dspath; zfs_handle_t *snap_hdl; nvlist_t *props; struct libbe_deep_clone *ldc; struct libbe_dccb dccb; ldc = (struct libbe_deep_clone *)data; dspath = zfs_get_name(ds); snprintf(snap_path, sizeof(snap_path), "%s@%s", dspath, ldc->snapname); /* construct the boot environment path from the dataset we're cloning */ if (be_get_path(ldc, dspath, be_path, sizeof(be_path)) != BE_ERR_SUCCESS) return (BE_ERR_UNKNOWN); /* the dataset to be created (i.e. the boot environment) already exists */ if (zfs_dataset_exists(ldc->lbh->lzh, be_path, ZFS_TYPE_DATASET)) return (BE_ERR_EXISTS); /* no snapshot found for this dataset, silently skip it */ if (!zfs_dataset_exists(ldc->lbh->lzh, snap_path, ZFS_TYPE_SNAPSHOT)) return (0); if ((snap_hdl = zfs_open(ldc->lbh->lzh, snap_path, ZFS_TYPE_SNAPSHOT)) == NULL) return (BE_ERR_ZFSOPEN); nvlist_alloc(&props, NV_UNIQUE_NAME, KM_SLEEP); nvlist_add_string(props, "canmount", "noauto"); dccb.lbh = ldc->lbh; dccb.zhp = ds; dccb.props = props; if (zprop_iter(be_deep_clone_prop, &dccb, B_FALSE, B_FALSE, ZFS_TYPE_FILESYSTEM) == ZPROP_INVAL) return (-1); if ((err = zfs_clone(snap_hdl, be_path, props)) != 0) return (BE_ERR_ZFSCLONE); nvlist_free(props); zfs_close(snap_hdl); if (ldc->depth_limit == -1 || ldc->depth < ldc->depth_limit) { ldc->depth++; err = zfs_iter_filesystems(ds, 0, be_clone_cb, ldc); ldc->depth--; } return (err); } /* * Create a boot environment with a given name from a given snapshot. * Snapshots can be in the format 'zroot/ROOT/default@snapshot' or * 'default@snapshot'. In the latter case, 'default@snapshot' will be prepended * with the root path that libbe was initailized with. */ static int be_clone(libbe_handle_t *lbh, const char *bename, const char *snapshot, int depth) { int err; char snap_path[BE_MAXPATHLEN]; char *parentname, *snapname; zfs_handle_t *parent_hdl; struct libbe_deep_clone ldc; /* ensure the boot environment name is valid */ if ((err = be_validate_name(lbh, bename)) != 0) return (set_error(lbh, err)); /* * prepend the boot environment root path if we're * given a partial snapshot name. */ if ((err = be_root_concat(lbh, snapshot, snap_path)) != 0) return (set_error(lbh, err)); /* ensure the snapshot exists */ if ((err = be_validate_snap(lbh, snap_path)) != 0) return (set_error(lbh, err)); /* get a copy of the snapshot path so we can disect it */ if ((parentname = strdup(snap_path)) == NULL) return (set_error(lbh, BE_ERR_UNKNOWN)); /* split dataset name from snapshot name */ snapname = strchr(parentname, '@'); if (snapname == NULL) { free(parentname); return (set_error(lbh, BE_ERR_UNKNOWN)); } *snapname = '\0'; snapname++; /* set-up the boot environment */ ldc.lbh = lbh; ldc.bename = bename; ldc.snapname = snapname; ldc.depth = 0; ldc.depth_limit = depth; /* the boot environment will be cloned from this dataset */ parent_hdl = zfs_open(lbh->lzh, parentname, ZFS_TYPE_DATASET); /* create the boot environment */ err = be_clone_cb(parent_hdl, &ldc); free(parentname); return (set_error(lbh, err)); } /* * Create a boot environment from pre-existing snapshot, specifying a depth. */ int be_create_depth(libbe_handle_t *lbh, const char *bename, const char *snap, int depth) { return (be_clone(lbh, bename, snap, depth)); } /* * Create the boot environment from pre-existing snapshot */ int be_create_from_existing_snap(libbe_handle_t *lbh, const char *bename, const char *snap) { return (be_clone(lbh, bename, snap, -1)); } /* * Create a boot environment from an existing boot environment */ int be_create_from_existing(libbe_handle_t *lbh, const char *bename, const char *old) { int err; char snap[BE_MAXPATHLEN]; if ((err = be_snapshot(lbh, old, NULL, true, snap)) != 0) return (set_error(lbh, err)); err = be_clone(lbh, bename, snap, -1); return (set_error(lbh, err)); } /* * Verifies that a snapshot has a valid name, exists, and has a mountpoint of * '/'. Returns BE_ERR_SUCCESS (0), upon success, or the relevant BE_ERR_* upon * failure. Does not set the internal library error state. */ int be_validate_snap(libbe_handle_t *lbh, const char *snap_name) { if (strlen(snap_name) >= BE_MAXPATHLEN) return (BE_ERR_PATHLEN); if (!zfs_name_valid(snap_name, ZFS_TYPE_SNAPSHOT)) return (BE_ERR_INVALIDNAME); if (!zfs_dataset_exists(lbh->lzh, snap_name, ZFS_TYPE_SNAPSHOT)) return (BE_ERR_NOENT); return (BE_ERR_SUCCESS); } /* * Idempotently appends the name argument to the root boot environment path * and copies the resulting string into the result buffer (which is assumed * to be at least BE_MAXPATHLEN characters long. Returns BE_ERR_SUCCESS upon * success, BE_ERR_PATHLEN if the resulting path is longer than BE_MAXPATHLEN, * or BE_ERR_INVALIDNAME if the name is a path that does not begin with * zfs_be_root. Does not set internal library error state. */ int be_root_concat(libbe_handle_t *lbh, const char *name, char *result) { size_t name_len, root_len; name_len = strlen(name); root_len = strlen(lbh->root); /* Act idempotently; return be name if it is already a full path */ if (strrchr(name, '/') != NULL) { if (strstr(name, lbh->root) != name) return (BE_ERR_INVALIDNAME); if (name_len >= BE_MAXPATHLEN) return (BE_ERR_PATHLEN); strlcpy(result, name, BE_MAXPATHLEN); return (BE_ERR_SUCCESS); } else if (name_len + root_len + 1 < BE_MAXPATHLEN) { snprintf(result, BE_MAXPATHLEN, "%s/%s", lbh->root, name); return (BE_ERR_SUCCESS); } return (BE_ERR_PATHLEN); } /* * Verifies the validity of a boot environment name (A-Za-z0-9-_.). Returns * BE_ERR_SUCCESS (0) if name is valid, otherwise returns BE_ERR_INVALIDNAME * or BE_ERR_PATHLEN. * Does not set internal library error state. */ int be_validate_name(libbe_handle_t *lbh, const char *name) { /* * Impose the additional restriction that the entire dataset name must * not exceed the maximum length of a dataset, i.e. MAXNAMELEN. */ if (strlen(lbh->root) + 1 + strlen(name) > MAXNAMELEN) return (BE_ERR_PATHLEN); if (!zfs_name_valid(name, ZFS_TYPE_DATASET)) return (BE_ERR_INVALIDNAME); /* * ZFS allows spaces in boot environment names, but the kernel can't * handle booting from such a dataset right now. vfs.root.mountfrom * is defined to be a space-separated list, and there's no protocol for * escaping whitespace in the path component of a dev:path spec. So * while loader can handle this situation alright, it can't safely pass * it on to mountroot. */ if (strchr(name, ' ') != NULL) return (BE_ERR_INVALIDNAME); return (BE_ERR_SUCCESS); } /* * usage */ int be_rename(libbe_handle_t *lbh, const char *old, const char *new) { char full_old[BE_MAXPATHLEN]; char full_new[BE_MAXPATHLEN]; zfs_handle_t *zfs_hdl; int err; /* * be_validate_name is documented not to set error state, so we should * do so here. */ if ((err = be_validate_name(lbh, new)) != 0) return (set_error(lbh, err)); if ((err = be_root_concat(lbh, old, full_old)) != 0) return (set_error(lbh, err)); if ((err = be_root_concat(lbh, new, full_new)) != 0) return (set_error(lbh, err)); if (!zfs_dataset_exists(lbh->lzh, full_old, ZFS_TYPE_DATASET)) return (set_error(lbh, BE_ERR_NOENT)); if (zfs_dataset_exists(lbh->lzh, full_new, ZFS_TYPE_DATASET)) return (set_error(lbh, BE_ERR_EXISTS)); if ((zfs_hdl = zfs_open(lbh->lzh, full_old, ZFS_TYPE_FILESYSTEM)) == NULL) return (set_error(lbh, BE_ERR_ZFSOPEN)); /* recurse, nounmount, forceunmount */ struct renameflags flags = { .nounmount = 1, }; err = zfs_rename(zfs_hdl, full_new, flags); zfs_close(zfs_hdl); if (err != 0) return (set_error(lbh, BE_ERR_UNKNOWN)); return (0); } int be_export(libbe_handle_t *lbh, const char *bootenv, int fd) { char snap_name[BE_MAXPATHLEN]; char buf[BE_MAXPATHLEN]; zfs_handle_t *zfs; sendflags_t flags = { 0 }; int err; if ((err = be_snapshot(lbh, bootenv, NULL, true, snap_name)) != 0) /* Use the error set by be_snapshot */ return (err); be_root_concat(lbh, snap_name, buf); if ((zfs = zfs_open(lbh->lzh, buf, ZFS_TYPE_DATASET)) == NULL) return (set_error(lbh, BE_ERR_ZFSOPEN)); err = zfs_send_one(zfs, NULL, fd, &flags, /* redactbook */ NULL); zfs_close(zfs); return (err); } int be_import(libbe_handle_t *lbh, const char *bootenv, int fd) { char buf[BE_MAXPATHLEN]; nvlist_t *props; zfs_handle_t *zfs; recvflags_t flags = { .nomount = 1 }; int err; be_root_concat(lbh, bootenv, buf); if ((err = zfs_receive(lbh->lzh, buf, NULL, &flags, fd, NULL)) != 0) { switch (err) { case EINVAL: return (set_error(lbh, BE_ERR_NOORIGIN)); case ENOENT: return (set_error(lbh, BE_ERR_NOENT)); case EIO: return (set_error(lbh, BE_ERR_IO)); default: return (set_error(lbh, BE_ERR_UNKNOWN)); } } if ((zfs = zfs_open(lbh->lzh, buf, ZFS_TYPE_FILESYSTEM)) == NULL) return (set_error(lbh, BE_ERR_ZFSOPEN)); nvlist_alloc(&props, NV_UNIQUE_NAME, KM_SLEEP); nvlist_add_string(props, "canmount", "noauto"); nvlist_add_string(props, "mountpoint", "none"); err = zfs_prop_set_list(zfs, props); nvlist_free(props); zfs_close(zfs); if (err != 0) return (set_error(lbh, BE_ERR_UNKNOWN)); return (0); } #if SOON static int be_create_child_noent(libbe_handle_t *lbh, const char *active, const char *child_path) { nvlist_t *props; zfs_handle_t *zfs; int err; nvlist_alloc(&props, NV_UNIQUE_NAME, KM_SLEEP); nvlist_add_string(props, "canmount", "noauto"); nvlist_add_string(props, "mountpoint", child_path); /* Create */ if ((err = zfs_create(lbh->lzh, active, ZFS_TYPE_DATASET, props)) != 0) { switch (err) { case EZFS_EXISTS: return (set_error(lbh, BE_ERR_EXISTS)); case EZFS_NOENT: return (set_error(lbh, BE_ERR_NOENT)); case EZFS_BADTYPE: case EZFS_BADVERSION: return (set_error(lbh, BE_ERR_NOPOOL)); case EZFS_BADPROP: default: /* We set something up wrong, probably... */ return (set_error(lbh, BE_ERR_UNKNOWN)); } } nvlist_free(props); if ((zfs = zfs_open(lbh->lzh, active, ZFS_TYPE_DATASET)) == NULL) return (set_error(lbh, BE_ERR_ZFSOPEN)); /* Set props */ if ((err = zfs_prop_set(zfs, "canmount", "noauto")) != 0) { zfs_close(zfs); /* * Similar to other cases, this shouldn't fail unless we've * done something wrong. This is a new dataset that shouldn't * have been mounted anywhere between creation and now. */ if (err == EZFS_NOMEM) return (set_error(lbh, BE_ERR_NOMEM)); return (set_error(lbh, BE_ERR_UNKNOWN)); } zfs_close(zfs); return (BE_ERR_SUCCESS); } static int be_create_child_cloned(libbe_handle_t *lbh, const char *active) { char buf[BE_MAXPATHLEN], tmp[BE_MAXPATHLEN];; zfs_handle_t *zfs; int err; /* XXX TODO ? */ /* * Establish if the existing path is a zfs dataset or just * the subdirectory of one */ strlcpy(tmp, "tmp/be_snap.XXXXX", sizeof(tmp)); if (mktemp(tmp) == NULL) return (set_error(lbh, BE_ERR_UNKNOWN)); be_root_concat(lbh, tmp, buf); printf("Here %s?\n", buf); if ((err = zfs_snapshot(lbh->lzh, buf, false, NULL)) != 0) { switch (err) { case EZFS_INVALIDNAME: return (set_error(lbh, BE_ERR_INVALIDNAME)); default: /* * The other errors that zfs_ioc_snapshot might return * shouldn't happen if we've set things up properly, so * we'll gloss over them and call it UNKNOWN as it will * require further triage. */ if (errno == ENOTSUP) return (set_error(lbh, BE_ERR_NOPOOL)); return (set_error(lbh, BE_ERR_UNKNOWN)); } } /* Clone */ if ((zfs = zfs_open(lbh->lzh, buf, ZFS_TYPE_SNAPSHOT)) == NULL) return (BE_ERR_ZFSOPEN); if ((err = zfs_clone(zfs, active, NULL)) != 0) /* XXX TODO correct error */ return (set_error(lbh, BE_ERR_UNKNOWN)); /* set props */ zfs_close(zfs); return (BE_ERR_SUCCESS); } int be_add_child(libbe_handle_t *lbh, const char *child_path, bool cp_if_exists) { struct stat sb; char active[BE_MAXPATHLEN], buf[BE_MAXPATHLEN]; nvlist_t *props; const char *s; /* Require absolute paths */ if (*child_path != '/') return (set_error(lbh, BE_ERR_BADPATH)); strlcpy(active, be_active_path(lbh), BE_MAXPATHLEN); strcpy(buf, active); /* Create non-mountable parent dataset(s) */ s = child_path; for (char *p; (p = strchr(s+1, '/')) != NULL; s = p) { size_t len = p - s; strncat(buf, s, len); nvlist_alloc(&props, NV_UNIQUE_NAME, KM_SLEEP); nvlist_add_string(props, "canmount", "off"); nvlist_add_string(props, "mountpoint", "none"); zfs_create(lbh->lzh, buf, ZFS_TYPE_DATASET, props); nvlist_free(props); } /* Path does not exist as a descendent of / yet */ if (strlcat(active, child_path, BE_MAXPATHLEN) >= BE_MAXPATHLEN) return (set_error(lbh, BE_ERR_PATHLEN)); if (stat(child_path, &sb) != 0) { /* Verify that error is ENOENT */ if (errno != ENOENT) return (set_error(lbh, BE_ERR_UNKNOWN)); return (be_create_child_noent(lbh, active, child_path)); } else if (cp_if_exists) /* Path is already a descendent of / and should be copied */ return (be_create_child_cloned(lbh, active)); return (set_error(lbh, BE_ERR_EXISTS)); } #endif /* SOON */ /* * Deactivate old BE dataset; currently just sets canmount=noauto or * resets boot once configuration. */ int be_deactivate(libbe_handle_t *lbh, const char *ds, bool temporary) { zfs_handle_t *zfs; if (temporary) { return (lzbe_set_boot_device( zpool_get_name(lbh->active_phandle), lzbe_add, NULL)); } if ((zfs = zfs_open(lbh->lzh, ds, ZFS_TYPE_DATASET)) == NULL) return (1); if (zfs_prop_set(zfs, "canmount", "noauto") != 0) return (1); zfs_close(zfs); return (0); } int be_activate(libbe_handle_t *lbh, const char *bootenv, bool temporary) { char be_path[BE_MAXPATHLEN]; nvlist_t *dsprops; char *origin; zfs_handle_t *zhp; int err; be_root_concat(lbh, bootenv, be_path); /* Note: be_exists fails if mountpoint is not / */ if ((err = be_exists(lbh, be_path)) != 0) return (set_error(lbh, err)); if (temporary) { return (lzbe_set_boot_device( zpool_get_name(lbh->active_phandle), lzbe_add, be_path)); } else { if (strncmp(lbh->bootfs, "-", 1) != 0 && be_deactivate(lbh, lbh->bootfs, false) != 0) return (-1); /* Obtain bootenv zpool */ err = zpool_set_prop(lbh->active_phandle, "bootfs", be_path); if (err) return (-1); zhp = zfs_open(lbh->lzh, be_path, ZFS_TYPE_FILESYSTEM); if (zhp == NULL) return (-1); if (be_prop_list_alloc(&dsprops) != 0) return (-1); if (be_get_dataset_props(lbh, be_path, dsprops) != 0) { nvlist_free(dsprops); return (-1); } if (nvlist_lookup_string(dsprops, "origin", &origin) == 0) err = zfs_promote(zhp); nvlist_free(dsprops); zfs_close(zhp); if (err) return (-1); } return (BE_ERR_SUCCESS); }