/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2017 Kyle J. Kneitinger <kyle@kneit.in>
* Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
* Copyright (c) 2019 Wes Maag <wes@jwmaag.org>
*
* 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/mntent.h>
#include "be.h"
#include "be_impl.h"
struct be_mountcheck_info {
const char *path;
char *name;
};
struct be_mount_info {
libbe_handle_t *lbh;
const char *be;
const char *mountpoint;
int mntflags;
int deepmount;
int depth;
};
static int
be_mountcheck_cb(zfs_handle_t *zfs_hdl, void *data)
{
struct be_mountcheck_info *info;
char *mountpoint;
if (data == NULL)
return (1);
info = (struct be_mountcheck_info *)data;
if (!zfs_is_mounted(zfs_hdl, &mountpoint))
return (0);
if (strcmp(mountpoint, info->path) == 0) {
info->name = strdup(zfs_get_name(zfs_hdl));
free(mountpoint);
return (1);
}
free(mountpoint);
return (0);
}
/*
* Called from be_mount, uses the given zfs_handle and attempts to
* mount it at the passed mountpoint. If the deepmount flag is set, continue
* calling the function for each child dataset.
*/
static int
be_mount_iter(zfs_handle_t *zfs_hdl, void *data)
{
int err;
char *mountpoint;
char tmp[BE_MAXPATHLEN], zfs_mnt[BE_MAXPATHLEN];
struct be_mount_info *info;
info = (struct be_mount_info *)data;
if (zfs_is_mounted(zfs_hdl, &mountpoint)) {
free(mountpoint);
return (0);
}
/*
* canmount and mountpoint are both ignored for the BE dataset, because
* the rest of the system (kernel and loader) will effectively do the
* same.
*/
if (info->depth == 0) {
snprintf(tmp, BE_MAXPATHLEN, "%s", info->mountpoint);
} else {
if (zfs_prop_get_int(zfs_hdl, ZFS_PROP_CANMOUNT) ==
ZFS_CANMOUNT_OFF)
return (0);
if (zfs_prop_get(zfs_hdl, ZFS_PROP_MOUNTPOINT, zfs_mnt,
BE_MAXPATHLEN, NULL, NULL, 0, 1))
return (1);
/*
* We've encountered mountpoint=none at some intermediate
* dataset (e.g. zroot/var) that will have children that may
* need to be mounted. Skip mounting it, but iterate through
* the children.
*/
if (strcmp("none", zfs_mnt) == 0)
goto skipmount;
mountpoint = be_mountpoint_augmented(info->lbh, zfs_mnt);
snprintf(tmp, BE_MAXPATHLEN, "%s%s", info->mountpoint,
mountpoint);
}
if ((err = zfs_mount_at(zfs_hdl, NULL, info->mntflags, tmp)) != 0) {
switch (errno) {
case ENAMETOOLONG:
return (set_error(info->lbh, BE_ERR_PATHLEN));
case ELOOP:
case ENOENT:
case ENOTDIR:
return (set_error(info->lbh, BE_ERR_BADPATH));
case EPERM:
return (set_error(info->lbh, BE_ERR_PERMS));
case EBUSY:
return (set_error(info->lbh, BE_ERR_PATHBUSY));
default:
return (set_error(info->lbh, BE_ERR_UNKNOWN));
}
}
if (!info->deepmount)
return (0);
skipmount:
++info->depth;
err = zfs_iter_filesystems(zfs_hdl, 0, be_mount_iter, info);
--info->depth;
return (err);
}
static int
be_umount_iter(zfs_handle_t *zfs_hdl, void *data)
{
int err;
char *mountpoint;
struct be_mount_info *info;
info = (struct be_mount_info *)data;
++info->depth;
if((err = zfs_iter_filesystems(zfs_hdl, 0, be_umount_iter, info)) != 0) {
return (err);
}
--info->depth;
if (!zfs_is_mounted(zfs_hdl, &mountpoint)) {
return (0);
}
free(mountpoint);
if (zfs_unmount(zfs_hdl, NULL, info->mntflags) != 0) {
switch (errno) {
case ENAMETOOLONG:
return (set_error(info->lbh, BE_ERR_PATHLEN));
case ELOOP:
case ENOENT:
case ENOTDIR:
return (set_error(info->lbh, BE_ERR_BADPATH));
case EPERM:
return (set_error(info->lbh, BE_ERR_PERMS));
case EBUSY:
return (set_error(info->lbh, BE_ERR_PATHBUSY));
default:
return (set_error(info->lbh, BE_ERR_UNKNOWN));
}
}
return (0);
}
/*
* usage
*/
int
be_mounted_at(libbe_handle_t *lbh, const char *path, nvlist_t *details)
{
char be[BE_MAXPATHLEN];
zfs_handle_t *root_hdl;
struct be_mountcheck_info info;
prop_data_t propinfo;
bzero(&be, BE_MAXPATHLEN);
if ((root_hdl = zfs_open(lbh->lzh, lbh->root,
ZFS_TYPE_FILESYSTEM)) == NULL)
return (BE_ERR_ZFSOPEN);
info.path = path;
info.name = NULL;
zfs_iter_filesystems(root_hdl, 0, be_mountcheck_cb, &info);
zfs_close(root_hdl);
if (info.name != NULL) {
if (details != NULL) {
if ((root_hdl = zfs_open(lbh->lzh, info.name,
ZFS_TYPE_FILESYSTEM)) == NULL) {
free(info.name);
return (BE_ERR_ZFSOPEN);
}
propinfo.lbh = lbh;
propinfo.list = details;
propinfo.single_object = false;
propinfo.bootonce = NULL;
prop_list_builder_cb(root_hdl, &propinfo);
zfs_close(root_hdl);
}
free(info.name);
return (0);
}
return (1);
}
/*
* usage
*/
int
be_mount(libbe_handle_t *lbh, const char *bootenv, const char *mountpoint,
int flags, char *result_loc)
{
char be[BE_MAXPATHLEN];
char mnt_temp[BE_MAXPATHLEN];
int mntflags, mntdeep;
int err;
struct be_mount_info info;
zfs_handle_t *zhdl;
if ((err = be_root_concat(lbh, bootenv, be)) != 0)
return (set_error(lbh, err));
if ((err = be_exists(lbh, bootenv)) != 0)
return (set_error(lbh, err));
if (is_mounted(lbh->lzh, be, NULL))
return (set_error(lbh, BE_ERR_MOUNTED));
mntdeep = (flags & BE_MNT_DEEP) ? 1 : 0;
mntflags = (flags & BE_MNT_FORCE) ? MNT_FORCE : 0;
/* Create mountpoint if it is not specified */
if (mountpoint == NULL) {
strlcpy(mnt_temp, "/tmp/be_mount.XXXX", sizeof(mnt_temp));
if (mkdtemp(mnt_temp) == NULL)
return (set_error(lbh, BE_ERR_IO));
}
if ((zhdl = zfs_open(lbh->lzh, be, ZFS_TYPE_FILESYSTEM)) == NULL)
return (set_error(lbh, BE_ERR_ZFSOPEN));
info.lbh = lbh;
info.be = be;
info.mountpoint = (mountpoint == NULL) ? mnt_temp : mountpoint;
info.mntflags = mntflags;
info.deepmount = mntdeep;
info.depth = 0;
if((err = be_mount_iter(zhdl, &info) != 0)) {
zfs_close(zhdl);
return (err);
}
zfs_close(zhdl);
if (result_loc != NULL)
strlcpy(result_loc, mountpoint == NULL ? mnt_temp : mountpoint,
BE_MAXPATHLEN);
return (BE_ERR_SUCCESS);
}
/*
* usage
*/
int
be_unmount(libbe_handle_t *lbh, const char *bootenv, int flags)
{
int err;
char be[BE_MAXPATHLEN];
zfs_handle_t *root_hdl;
struct be_mount_info info;
if ((err = be_root_concat(lbh, bootenv, be)) != 0)
return (set_error(lbh, err));
if ((root_hdl = zfs_open(lbh->lzh, be, ZFS_TYPE_FILESYSTEM)) == NULL)
return (set_error(lbh, BE_ERR_ZFSOPEN));
info.lbh = lbh;
info.be = be;
info.mountpoint = NULL;
info.mntflags = (flags & BE_MNT_FORCE) ? MS_FORCE : 0;
info.depth = 0;
if ((err = be_umount_iter(root_hdl, &info)) != 0) {
zfs_close(root_hdl);
return (err);
}
zfs_close(root_hdl);
return (BE_ERR_SUCCESS);
}
/*
* This function will blow away the input buffer as needed if we're discovered
* to be looking at a root-mount. If the mountpoint is naturally beyond the
* root, however, the buffer may be left intact and a pointer to the section
* past altroot will be returned instead for the caller's perusal.
*/
char *
be_mountpoint_augmented(libbe_handle_t *lbh, char *mountpoint)
{
if (lbh->altroot_len == 0)
return (mountpoint);
if (mountpoint == NULL || *mountpoint == '\0')
return (mountpoint);
if (mountpoint[lbh->altroot_len] == '\0') {
*(mountpoint + 1) = '\0';
return (mountpoint);
} else
return (mountpoint + lbh->altroot_len);
}
