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be.c
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/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2017 Kyle J. Kneitinger <[email protected]>
*
* 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/ucred.h>
#include <sys/queue.h>
#include <sys/zfs_context.h>
#include <sys/mntent.h>
#include <ctype.h>
#include <libgen.h>
#include <libzfs_core.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#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, 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, 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, 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, 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 (set_error(ldc->lbh, 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 (set_error(ldc->lbh, 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 (set_error(ldc->lbh, 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 (set_error(ldc->lbh, 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, be_clone_cb, ldc);
ldc->depth--;
}
return (set_error(ldc->lbh, 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);
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,
};