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Diffstat (limited to 'cmd/mount_zfs/mount_zfs.c')
| -rw-r--r-- | cmd/mount_zfs/mount_zfs.c | 470 |
1 files changed, 470 insertions, 0 deletions
diff --git a/cmd/mount_zfs/mount_zfs.c b/cmd/mount_zfs/mount_zfs.c new file mode 100644 index 000000000..32f092199 --- /dev/null +++ b/cmd/mount_zfs/mount_zfs.c @@ -0,0 +1,470 @@ +/* + * 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2011 Lawrence Livermore National Security, LLC. + */ + +#include <libintl.h> +#include <unistd.h> +#include <sys/file.h> +#include <sys/mount.h> +#include <sys/stat.h> +#include <libzfs.h> +#ifdef HAVE_LIBSELINUX +#include <selinux/selinux.h> +#endif /* HAVE_LIBSELINUX */ + +libzfs_handle_t *g_zfs; + +typedef struct option_map { + const char *name; + unsigned long mntmask; + unsigned long zfsmask; +} option_map_t; + +static const option_map_t option_map[] = { + /* Canonicalized filesystem independent options from mount(8) */ + { MNTOPT_NOAUTO, MS_COMMENT, ZS_COMMENT }, + { MNTOPT_DEFAULTS, MS_COMMENT, ZS_COMMENT }, + { MNTOPT_NODEVICES, MS_NODEV, ZS_COMMENT }, + { MNTOPT_DIRSYNC, MS_DIRSYNC, ZS_COMMENT }, + { MNTOPT_NOEXEC, MS_NOEXEC, ZS_COMMENT }, + { MNTOPT_GROUP, MS_GROUP, ZS_COMMENT }, + { MNTOPT_NETDEV, MS_COMMENT, ZS_COMMENT }, + { MNTOPT_NOFAIL, MS_COMMENT, ZS_COMMENT }, + { MNTOPT_NOSUID, MS_NOSUID, ZS_COMMENT }, + { MNTOPT_OWNER, MS_OWNER, ZS_COMMENT }, + { MNTOPT_REMOUNT, MS_REMOUNT, ZS_COMMENT }, + { MNTOPT_RO, MS_RDONLY, ZS_COMMENT }, + { MNTOPT_RW, MS_COMMENT, ZS_COMMENT }, + { MNTOPT_SYNC, MS_SYNCHRONOUS, ZS_COMMENT }, + { MNTOPT_USER, MS_USERS, ZS_COMMENT }, + { MNTOPT_USERS, MS_USERS, ZS_COMMENT }, +#ifdef MS_NOATIME + { MNTOPT_NOATIME, MS_NOATIME, ZS_COMMENT }, +#endif +#ifdef MS_NODIRATIME + { MNTOPT_NODIRATIME, MS_NODIRATIME, ZS_COMMENT }, +#endif +#ifdef MS_RELATIME + { MNTOPT_RELATIME, MS_RELATIME, ZS_COMMENT }, +#endif +#ifdef MS_STRICTATIME + { MNTOPT_DFRATIME, MS_STRICTATIME, ZS_COMMENT }, +#endif +#ifdef HAVE_SELINUX + { MNTOPT_CONTEXT, MS_COMMENT, ZS_NOCONTEXT }, + { MNTOPT_NOCONTEXT, MS_COMMENT, ZS_NOCONTEXT }, + { MNTOPT_FSCONTEXT, MS_COMMENT, ZS_NOCONTEXT }, + { MNTOPT_DEFCONTEXT, MS_COMMENT, ZS_NOCONTEXT }, + { MNTOPT_ROOTCONTEXT, MS_COMMENT, ZS_NOCONTEXT }, +#endif +#ifdef MS_I_VERSION + { MNTOPT_IVERSION, MS_I_VERSION, ZS_COMMENT }, +#endif +#ifdef MS_MANDLOCK + { MNTOPT_NBMAND, MS_MANDLOCK, ZS_COMMENT }, +#endif + /* Valid options not found in mount(8) */ + { MNTOPT_BIND, MS_BIND, ZS_COMMENT }, +#ifdef MS_REC + { MNTOPT_RBIND, MS_BIND|MS_REC, ZS_COMMENT }, +#endif + { MNTOPT_COMMENT, MS_COMMENT, ZS_COMMENT }, +#ifdef MS_NOSUB + { MNTOPT_NOSUB, MS_NOSUB, ZS_COMMENT }, +#endif +#ifdef MS_SILENT + { MNTOPT_QUIET, MS_SILENT, ZS_COMMENT }, +#endif + /* Custom zfs options */ + { MNTOPT_NOXATTR, MS_COMMENT, ZS_COMMENT }, + { MNTOPT_ZFSUTIL, MS_COMMENT, ZS_ZFSUTIL }, + { NULL, 0, 0 } }; + +/* + * Break the mount option in to a name/value pair. The name is + * validated against the option map and mount flags set accordingly. + */ +static int +parse_option(char *mntopt, unsigned long *mntflags, + unsigned long *zfsflags, int sloppy) +{ + const option_map_t *opt; + char *ptr, *name, *value = NULL; + int error = 0; + + name = strdup(mntopt); + if (name == NULL) + return (ENOMEM); + + for (ptr = name; ptr && *ptr; ptr++) { + if (*ptr == '=') { + *ptr = '\0'; + value = ptr+1; + break; + } + } + + for (opt = option_map; opt->name != NULL; opt++) { + if (strncmp(name, opt->name, strlen(name)) == 0) { + *mntflags |= opt->mntmask; + *zfsflags |= opt->zfsmask; + + /* MS_USERS implies default user options */ + if (opt->mntmask & (MS_USERS)) + *mntflags |= (MS_NOEXEC|MS_NOSUID|MS_NODEV); + + /* MS_OWNER|MS_GROUP imply default owner options */ + if (opt->mntmask & (MS_OWNER | MS_GROUP)) + *mntflags |= (MS_NOSUID|MS_NODEV); + + error = 0; + goto out; + } + } + + if (!sloppy) + error = ENOENT; +out: + /* If required further process on the value may be done here */ + free(name); + return (error); +} + +/* + * Translate the mount option string in to MS_* mount flags for the + * kernel vfs. When sloppy is non-zero unknown options will be ignored + * otherwise they are considered fatal are copied in to badopt. + */ +static int +parse_options(char *mntopts, unsigned long *mntflags, + unsigned long *zfsflags, int sloppy, char *badopt) +{ + int error = 0, quote = 0, flag = 0; + char *ptr, *opt, *opts; + + opts = strdup(mntopts); + if (opts == NULL) + return (ENOMEM); + + *mntflags = 0; + opt = NULL; + + /* + * Scan through all mount options which must be comma delimited. + * We must be careful to notice regions which are double quoted + * and skip commas in these regions. Each option is then checked + * to determine if it is a known option. + */ + for (ptr = opts; ptr && !flag; ptr++) { + if (opt == NULL) + opt = ptr; + + if (*ptr == '"') + quote = !quote; + + if (quote) + continue; + + if (*ptr == '\0') + flag = 1; + + if ((*ptr == ',') || (*ptr == '\0')) { + *ptr = '\0'; + + error = parse_option(opt, mntflags, zfsflags, sloppy); + if (error) { + strcpy(badopt, opt); + goto out; + } + + opt = NULL; + } + } + +out: + free(opts); + return (error); +} + +/* + * If a file or directory in your current working directory is named + * 'dataset' then mount(8) will prepend your current working directory + * to dataset. The is no way to prevent this behavior so we simply + * check for it and strip the prepended patch when it is added. + */ +static char * +parse_dataset(char *dataset) +{ + char cwd[PATH_MAX]; + + (void) getcwd(cwd, PATH_MAX); + if (!strncmp(cwd, dataset, strlen(cwd))) + return (dataset + strlen(cwd) + 1); + + return (dataset); +} + +/* + * Update the mtab_* code to use the libmount library when it is commonly + * available otherwise fallback to legacy mode. The mount(8) utility will + * manage the lock file for us to prevent racing updates to /etc/mtab. + */ +static int +mtab_is_writeable(void) +{ + struct stat st; + int error, fd; + + error = stat(MNTTAB, &st); + if (error || S_ISLNK(st.st_mode)) + return (0); + + fd = open(MNTTAB, O_RDWR | O_CREAT, 0644); + if (fd < 0) + return (0); + + close(fd); + return (1); +} + +static int +mtab_update(char *dataset, char *mntpoint, char *type, char *mntopts) +{ + struct mntent mnt; + FILE *fp; + int error; + + mnt.mnt_fsname = dataset; + mnt.mnt_dir = mntpoint; + mnt.mnt_type = type; + mnt.mnt_opts = mntopts ? mntopts : ""; + mnt.mnt_freq = 0; + mnt.mnt_passno = 0; + + fp = setmntent(MNTTAB, "a+"); + if (!fp) { + (void) fprintf(stderr, gettext( + "filesystem '%s' was mounted, but %s " + "could not be opened due to error %d\n"), + dataset, MNTTAB, errno); + return (MOUNT_FILEIO); + } + + error = addmntent(fp, &mnt); + if (error) { + (void) fprintf(stderr, gettext( + "filesystem '%s' was mounted, but %s " + "could not be updated due to error %d\n"), + dataset, MNTTAB, errno); + return (MOUNT_FILEIO); + } + + (void) endmntent(fp); + + return (MOUNT_SUCCESS); +} + +int +main(int argc, char **argv) +{ + zfs_handle_t *zhp; + char legacy[ZFS_MAXPROPLEN]; + char mntopts[MNT_LINE_MAX] = { '\0' }; + char badopt[MNT_LINE_MAX] = { '\0' }; + char *dataset, *mntpoint; + unsigned long mntflags = 0, zfsflags = 0; + int sloppy = 0, fake = 0, verbose = 0, nomtab = 0, zfsutil = 0; + int error, c; + + (void) setlocale(LC_ALL, ""); + (void) textdomain(TEXT_DOMAIN); + + opterr = 0; + + /* check options */ + while ((c = getopt(argc, argv, "sfnvo:h?")) != -1) { + switch (c) { + case 's': + sloppy = 1; + break; + case 'f': + fake = 1; + break; + case 'n': + nomtab = 1; + break; + case 'v': + verbose++; + break; + case 'o': + (void) strlcpy(mntopts, optarg, sizeof (mntopts)); + break; + case 'h': + case '?': + (void) fprintf(stderr, gettext("Invalid option '%c'\n"), + optopt); + (void) fprintf(stderr, gettext("Usage: mount.zfs " + "[-sfnv] [-o options] <dataset> <mountpoint>\n")); + return (MOUNT_USAGE); + } + } + + argc -= optind; + argv += optind; + + /* check that we only have two arguments */ + if (argc != 2) { + if (argc == 0) + (void) fprintf(stderr, gettext("missing dataset " + "argument\n")); + else if (argc == 1) + (void) fprintf(stderr, + gettext("missing mountpoint argument\n")); + else + (void) fprintf(stderr, gettext("too many arguments\n")); + (void) fprintf(stderr, "usage: mount <dataset> <mountpoint>\n"); + return (MOUNT_USAGE); + } + + dataset = parse_dataset(argv[0]); + mntpoint = argv[1]; + + /* validate mount options and set mntflags */ + error = parse_options(mntopts, &mntflags, &zfsflags, sloppy, badopt); + if (error) { + switch (error) { + case ENOMEM: + (void) fprintf(stderr, gettext("filesystem '%s' " + "cannot be mounted due to a memory allocation " + "failure\n"), dataset); + return (MOUNT_SYSERR); + case EINVAL: + (void) fprintf(stderr, gettext("filesystem '%s' " + "cannot be mounted of due to the invalid option " + "'%s'\n"), dataset, badopt); + (void) fprintf(stderr, gettext("Use the '-s' option " + "to ignore the bad mount option.\n")); + return (MOUNT_USAGE); + default: + (void) fprintf(stderr, gettext("filesystem '%s' " + "cannot be mounted due to internal error %d\n"), + dataset, error); + return (MOUNT_SOFTWARE); + } + } + +#ifdef HAVE_LIBSELINUX + /* + * Automatically add the default zfs context when selinux is enabled + * and the caller has not specified their own context. This must be + * done until zfs is added to the default selinux policy configuration + * as a known filesystem type which supports xattrs. + */ + if (is_selinux_enabled() && !(zfsflags & ZS_NOCONTEXT)) + (void) strlcat(mntopts, ",context=\"system_u:" + "object_r:file_t:s0\"", sizeof (mntopts)); +#endif /* HAVE_LIBSELINUX */ + + + if (verbose) + (void) fprintf(stdout, gettext("mount.zfs:\n" + " dataset: \"%s\"\n mountpoint: \"%s\"\n" + " mountflags: 0x%lx\n zfsflags: 0x%lx\n" + " mountopts: \"%s\"\n\n"), + dataset, mntpoint, mntflags, zfsflags, mntopts); + + if (mntflags & MS_REMOUNT) + nomtab = 1; + + if (zfsflags * ZS_ZFSUTIL) + zfsutil = 1; + + if ((g_zfs = libzfs_init()) == NULL) + return (MOUNT_SYSERR); + + /* try to open the dataset to access the mount point */ + if ((zhp = zfs_open(g_zfs, dataset, ZFS_TYPE_FILESYSTEM)) == NULL) { + (void) fprintf(stderr, gettext("filesystem '%s' cannot be " + "mounted, unable to open the dataset\n"), dataset); + libzfs_fini(g_zfs); + return (MOUNT_USAGE); + } + + (void) zfs_prop_get(zhp, ZFS_PROP_MOUNTPOINT, legacy, + sizeof (legacy), NULL, NULL, 0, B_FALSE); + + zfs_close(zhp); + libzfs_fini(g_zfs); + + /* + * Legacy mount points may only be mounted using 'mount', never using + * 'zfs mount'. However, since 'zfs mount' actually invokes 'mount' + * we differentiate the two cases using the 'zfsutil' mount option. + * This mount option should only be supplied by the 'zfs mount' util. + */ + if (zfsutil && !strcmp(legacy, ZFS_MOUNTPOINT_LEGACY)) { + (void) fprintf(stderr, gettext( + "filesystem '%s' cannot be mounted using 'zfs mount'.\n" + "Use 'zfs set mountpoint=%s' or 'mount -t zfs %s %s'.\n" + "See zfs(8) for more information.\n"), + dataset, mntpoint, dataset, mntpoint); + return (MOUNT_USAGE); + } + + if (!zfsutil && strcmp(legacy, ZFS_MOUNTPOINT_LEGACY)) { + (void) fprintf(stderr, gettext( + "filesystem '%s' cannot be mounted using 'mount'.\n" + "Use 'zfs set mountpoint=%s' or 'zfs mount %s'.\n" + "See zfs(8) for more information.\n"), + dataset, "legacy", dataset); + return (MOUNT_USAGE); + } + + if (!fake) { + error = mount(dataset, mntpoint, MNTTYPE_ZFS, + mntflags, mntopts); + if (error) { + switch (errno) { + case EBUSY: + (void) fprintf(stderr, gettext("filesystem " + "'%s' is already mounted\n"), dataset); + return (MOUNT_SYSERR); + default: + (void) fprintf(stderr, gettext("filesystem " + "'%s' can not be mounted due to error " + "%d\n"), dataset, errno); + return (MOUNT_USAGE); + } + } + } + + if (!nomtab && mtab_is_writeable()) { + error = mtab_update(dataset, mntpoint, MNTTYPE_ZFS, mntopts); + if (error) + return (error); + } + + return (MOUNT_SUCCESS); +} |