1 /* vi: set sw=4 ts=4: */
3 * Mini mount implementation for busybox
5 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
6 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
7 * Copyright (C) 2005-2006 by Rob Landley <rob@landley.net>
9 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
11 // Design notes: There is no spec for mount. Remind me to write one.
13 // mount_main() calls singlemount() which calls mount_it_now().
15 // mount_main() can loop through /etc/fstab for mount -a
16 // singlemount() can loop through /etc/filesystems for fstype detection.
17 // mount_it_now() does the actual mount.
21 //config: bool "mount"
23 //config: select PLATFORM_LINUX
25 //config: All files and filesystems in Unix are arranged into one big directory
26 //config: tree. The 'mount' utility is used to graft a filesystem onto a
27 //config: particular part of the tree. A filesystem can either live on a block
28 //config: device, or it can be accessible over the network, as is the case with
29 //config: NFS filesystems. Most people using BusyBox will also want to enable
30 //config: the 'mount' utility.
32 //config:config FEATURE_MOUNT_FAKE
33 //config: bool "Support option -f"
35 //config: depends on MOUNT
37 //config: Enable support for faking a file system mount.
39 //config:config FEATURE_MOUNT_VERBOSE
40 //config: bool "Support option -v"
42 //config: depends on MOUNT
44 //config: Enable multi-level -v[vv...] verbose messages. Useful if you
45 //config: debug mount problems and want to see what is exactly passed
46 //config: to the kernel.
48 //config:config FEATURE_MOUNT_HELPERS
49 //config: bool "Support mount helpers"
51 //config: depends on MOUNT
53 //config: Enable mounting of virtual file systems via external helpers.
54 //config: E.g. "mount obexfs#-b00.11.22.33.44.55 /mnt" will in effect call
55 //config: "obexfs -b00.11.22.33.44.55 /mnt"
56 //config: Also "mount -t sometype [-o opts] fs /mnt" will try
57 //config: "sometype [-o opts] fs /mnt" if simple mount syscall fails.
58 //config: The idea is to use such virtual filesystems in /etc/fstab.
60 //config:config FEATURE_MOUNT_LABEL
61 //config: bool "Support specifying devices by label or UUID"
63 //config: depends on MOUNT
64 //config: select VOLUMEID
66 //config: This allows for specifying a device by label or uuid, rather than by
67 //config: name. This feature utilizes the same functionality as blkid/findfs.
68 //config: This also enables label or uuid support for swapon.
70 //config:config FEATURE_MOUNT_NFS
71 //config: bool "Support mounting NFS file systems on Linux < 2.6.23"
73 //config: depends on MOUNT
74 //config: select FEATURE_HAVE_RPC
75 //config: select FEATURE_SYSLOG
77 //config: Enable mounting of NFS file systems on Linux kernels prior
78 //config: to version 2.6.23. Note that in this case mounting of NFS
79 //config: over IPv6 will not be possible.
81 //config: Note that this option links in RPC support from libc,
82 //config: which is rather large (~10 kbytes on uclibc).
84 //config:config FEATURE_MOUNT_CIFS
85 //config: bool "Support mounting CIFS/SMB file systems"
87 //config: depends on MOUNT
89 //config: Enable support for samba mounts.
91 //config:config FEATURE_MOUNT_FLAGS
92 //config: depends on MOUNT
93 //config: bool "Support lots of -o flags in mount"
96 //config: Without this, mount only supports ro/rw/remount. With this, it
97 //config: supports nosuid, suid, dev, nodev, exec, noexec, sync, async, atime,
98 //config: noatime, diratime, nodiratime, loud, bind, move, shared, slave,
99 //config: private, unbindable, rshared, rslave, rprivate, and runbindable.
101 //config:config FEATURE_MOUNT_FSTAB
102 //config: depends on MOUNT
103 //config: bool "Support /etc/fstab and -a"
106 //config: Support mount all and looking for files in /etc/fstab.
108 //config:config FEATURE_MOUNT_OTHERTAB
109 //config: depends on FEATURE_MOUNT_FSTAB
110 //config: bool "Support -T <alt_fstab>"
113 //config: Support mount -T (specifying an alternate fstab)
115 //usage:#define mount_trivial_usage
116 //usage: "[OPTIONS] [-o OPT] DEVICE NODE"
117 //usage:#define mount_full_usage "\n\n"
118 //usage: "Mount a filesystem. Filesystem autodetection requires /proc.\n"
119 //usage: "\n -a Mount all filesystems in fstab"
120 //usage: IF_FEATURE_MOUNT_FAKE(
121 //usage: IF_FEATURE_MTAB_SUPPORT(
122 //usage: "\n -f Update /etc/mtab, but don't mount"
124 //usage: IF_NOT_FEATURE_MTAB_SUPPORT(
125 //usage: "\n -f Dry run"
128 //usage: IF_FEATURE_MOUNT_HELPERS(
129 //usage: "\n -i Don't run mount helper"
131 //usage: IF_FEATURE_MTAB_SUPPORT(
132 //usage: "\n -n Don't update /etc/mtab"
134 //usage: IF_FEATURE_MOUNT_VERBOSE(
135 //usage: "\n -v Verbose"
137 ////usage: "\n -s Sloppy (ignored)"
138 //usage: "\n -r Read-only mount"
139 ////usage: "\n -w Read-write mount (default)"
140 //usage: "\n -t FSTYPE[,...] Filesystem type(s)"
141 //usage: IF_FEATURE_MOUNT_OTHERTAB(
142 //usage: "\n -T FILE Read FILE instead of /etc/fstab"
144 //usage: "\n -O OPT Mount only filesystems with option OPT (-a only)"
146 //usage: IF_FEATURE_MOUNT_LOOP(
147 //usage: "\n loop Ignored (loop devices are autodetected)"
149 //usage: IF_FEATURE_MOUNT_FLAGS(
150 //usage: "\n [a]sync Writes are [a]synchronous"
151 //usage: "\n [no]atime Disable/enable updates to inode access times"
152 //usage: "\n [no]diratime Disable/enable atime updates to directories"
153 //usage: "\n [no]relatime Disable/enable atime updates relative to modification time"
154 //usage: "\n [no]dev (Dis)allow use of special device files"
155 //usage: "\n [no]exec (Dis)allow use of executable files"
156 //usage: "\n [no]suid (Dis)allow set-user-id-root programs"
157 //usage: "\n [r]shared Convert [recursively] to a shared subtree"
158 //usage: "\n [r]slave Convert [recursively] to a slave subtree"
159 //usage: "\n [r]private Convert [recursively] to a private subtree"
160 //usage: "\n [un]bindable Make mount point [un]able to be bind mounted"
161 //usage: "\n [r]bind Bind a file or directory [recursively] to another location"
162 //usage: "\n move Relocate an existing mount point"
164 //usage: "\n remount Remount a mounted filesystem, changing flags"
165 //usage: "\n ro Same as -r"
167 //usage: "\nThere are filesystem-specific -o flags."
169 //usage:#define mount_example_usage
171 //usage: "/dev/hda3 on / type minix (rw)\n"
172 //usage: "proc on /proc type proc (rw)\n"
173 //usage: "devpts on /dev/pts type devpts (rw)\n"
174 //usage: "$ mount /dev/fd0 /mnt -t msdos -o ro\n"
175 //usage: "$ mount /tmp/diskimage /opt -t ext2 -o loop\n"
176 //usage: "$ mount cd_image.iso mydir\n"
177 //usage:#define mount_notes_usage
178 //usage: "Returns 0 for success, number of failed mounts for -a, or errno for one mount."
182 #include <sys/mount.h>
183 // Grab more as needed from util-linux's mount/mount_constants.h
185 # define MS_DIRSYNC (1 << 7) // Directory modifications are synchronous
188 # define MS_UNION (1 << 8)
191 # define MS_BIND (1 << 12)
194 # define MS_MOVE (1 << 13)
197 # define MS_RECURSIVE (1 << 14)
200 # define MS_SILENT (1 << 15)
202 // The shared subtree stuff, which went in around 2.6.15
203 #ifndef MS_UNBINDABLE
204 # define MS_UNBINDABLE (1 << 17)
207 # define MS_PRIVATE (1 << 18)
210 # define MS_SLAVE (1 << 19)
213 # define MS_SHARED (1 << 20)
216 # define MS_RELATIME (1 << 21)
218 #ifndef MS_STRICTATIME
219 # define MS_STRICTATIME (1 << 24)
222 /* Any ~MS_FOO value has this bit set: */
223 #define BB_MS_INVERTED_VALUE (1u << 31)
226 #if ENABLE_FEATURE_MOUNT_LABEL
227 # include "volume_id.h"
229 # define resolve_mount_spec(fsname) ((void)0)
232 // Needed for nfs support only
233 #include <sys/utsname.h>
236 #if ENABLE_FEATURE_MOUNT_NFS
237 /* This is just a warning of a common mistake. Possibly this should be a
238 * uclibc faq entry rather than in busybox... */
239 # if defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
240 # error "You need to build uClibc with UCLIBC_HAS_RPC for NFS support"
242 # include <rpc/rpc.h>
243 # include <rpc/pmap_prot.h>
244 # include <rpc/pmap_clnt.h>
248 #if defined(__dietlibc__)
249 // 16.12.2006, Sampo Kellomaki (sampo@iki.fi)
250 // dietlibc-0.30 does not have implementation of getmntent_r()
251 static struct mntent *getmntent_r(FILE* stream, struct mntent* result,
252 char* buffer UNUSED_PARAM, int bufsize UNUSED_PARAM)
254 struct mntent* ment = getmntent(stream);
255 return memcpy(result, ment, sizeof(*ment));
260 // Not real flags, but we want to be able to check for this.
262 MOUNT_USERS = (1 << 28) * ENABLE_DESKTOP,
263 MOUNT_NOAUTO = (1 << 29),
264 MOUNT_SWAP = (1 << 30),
268 #define OPTION_STR "o:t:rwanfvsiO:" IF_FEATURE_MOUNT_OTHERTAB("T:")
284 #if ENABLE_FEATURE_MTAB_SUPPORT
285 #define USE_MTAB (!(option_mask32 & OPT_n))
290 #if ENABLE_FEATURE_MOUNT_FAKE
291 #define FAKE_IT (option_mask32 & OPT_f)
296 #if ENABLE_FEATURE_MOUNT_HELPERS
297 #define HELPERS_ALLOWED (!(option_mask32 & OPT_i))
299 #define HELPERS_ALLOWED 0
303 // TODO: more "user" flag compatibility.
304 // "user" option (from mount manpage):
305 // Only the user that mounted a filesystem can unmount it again.
306 // If any user should be able to unmount, then use users instead of user
307 // in the fstab line. The owner option is similar to the user option,
308 // with the restriction that the user must be the owner of the special file.
309 // This may be useful e.g. for /dev/fd if a login script makes
310 // the console user owner of this device.
312 // Standard mount options (from -o options or --options),
313 // with corresponding flags
314 static const int32_t mount_options[] = {
315 // MS_FLAGS set a bit. ~MS_FLAGS disable that bit. 0 flags are NOPs.
317 IF_FEATURE_MOUNT_LOOP(
321 IF_FEATURE_MOUNT_FSTAB(
323 /* "quiet" 0 - do not filter out, vfat wants to see it */
324 /* "noauto" */ MOUNT_NOAUTO,
325 /* "sw" */ MOUNT_SWAP,
326 /* "swap" */ MOUNT_SWAP,
327 IF_DESKTOP(/* "user" */ MOUNT_USERS,)
328 IF_DESKTOP(/* "users" */ MOUNT_USERS,)
330 IF_DESKTOP(/* "comment=" */ 0,) /* systemd uses this in fstab */
333 IF_FEATURE_MOUNT_FLAGS(
335 /* "nosuid" */ MS_NOSUID,
336 /* "suid" */ ~MS_NOSUID,
337 /* "dev" */ ~MS_NODEV,
338 /* "nodev" */ MS_NODEV,
339 /* "exec" */ ~MS_NOEXEC,
340 /* "noexec" */ MS_NOEXEC,
341 /* "sync" */ MS_SYNCHRONOUS,
342 /* "dirsync" */ MS_DIRSYNC,
343 /* "async" */ ~MS_SYNCHRONOUS,
344 /* "atime" */ ~MS_NOATIME,
345 /* "noatime" */ MS_NOATIME,
346 /* "diratime" */ ~MS_NODIRATIME,
347 /* "nodiratime" */ MS_NODIRATIME,
348 /* "mand" */ MS_MANDLOCK,
349 /* "nomand" */ ~MS_MANDLOCK,
350 /* "relatime" */ MS_RELATIME,
351 /* "norelatime" */ ~MS_RELATIME,
352 /* "strictatime" */ MS_STRICTATIME,
353 /* "loud" */ ~MS_SILENT,
354 /* "rbind" */ MS_BIND|MS_RECURSIVE,
357 /* "union" */ MS_UNION,
358 /* "bind" */ MS_BIND,
359 /* "move" */ MS_MOVE,
360 /* "shared" */ MS_SHARED,
361 /* "slave" */ MS_SLAVE,
362 /* "private" */ MS_PRIVATE,
363 /* "unbindable" */ MS_UNBINDABLE,
364 /* "rshared" */ MS_SHARED|MS_RECURSIVE,
365 /* "rslave" */ MS_SLAVE|MS_RECURSIVE,
366 /* "rprivate" */ MS_PRIVATE|MS_RECURSIVE,
367 /* "runbindable" */ MS_UNBINDABLE|MS_RECURSIVE,
370 // Always understood.
371 /* "ro" */ MS_RDONLY, // vfs flag
372 /* "rw" */ ~MS_RDONLY, // vfs flag
373 /* "remount" */ MS_REMOUNT // action flag
376 static const char mount_option_str[] =
377 IF_FEATURE_MOUNT_LOOP(
380 IF_FEATURE_MOUNT_FSTAB(
382 // "quiet\0" - do not filter out, vfat wants to see it
387 IF_DESKTOP("users\0")
389 IF_DESKTOP("comment=\0") /* systemd uses this in fstab */
391 IF_FEATURE_MOUNT_FLAGS(
428 // Always understood.
431 "remount\0" // action flag
436 #if ENABLE_FEATURE_MOUNT_NFS
437 smalluint nfs_mount_version;
439 #if ENABLE_FEATURE_MOUNT_VERBOSE
443 char getmntent_buf[1];
445 enum { GETMNTENT_BUFSIZE = COMMON_BUFSIZE - offsetof(struct globals, getmntent_buf) };
446 #define G (*(struct globals*)&bb_common_bufsiz1)
447 #define nfs_mount_version (G.nfs_mount_version)
448 #if ENABLE_FEATURE_MOUNT_VERBOSE
449 #define verbose (G.verbose )
453 #define fslist (G.fslist )
454 #define getmntent_buf (G.getmntent_buf )
455 #define INIT_G() do { } while (0)
457 #if ENABLE_FEATURE_MTAB_SUPPORT
459 * update_mtab_entry_on_move() is used to update entry in case of mount --move.
460 * we are looking for existing entries mnt_dir which is equal to mnt_fsname of
461 * input mntent and replace it by new one.
463 static void FAST_FUNC update_mtab_entry_on_move(const struct mntent *mp)
465 struct mntent *entries, *m;
469 mountTable = setmntent(bb_path_mtab_file, "r");
471 bb_perror_msg(bb_path_mtab_file);
477 while ((m = getmntent(mountTable)) != NULL) {
478 entries = xrealloc_vector(entries, 3, count);
479 entries[count].mnt_fsname = xstrdup(m->mnt_fsname);
480 entries[count].mnt_dir = xstrdup(m->mnt_dir);
481 entries[count].mnt_type = xstrdup(m->mnt_type);
482 entries[count].mnt_opts = xstrdup(m->mnt_opts);
483 entries[count].mnt_freq = m->mnt_freq;
484 entries[count].mnt_passno = m->mnt_passno;
487 endmntent(mountTable);
489 mountTable = setmntent(bb_path_mtab_file, "w");
491 for (i = 0; i < count; i++) {
492 if (strcmp(entries[i].mnt_dir, mp->mnt_fsname) != 0)
493 addmntent(mountTable, &entries[i]);
495 addmntent(mountTable, mp);
497 endmntent(mountTable);
498 } else if (errno != EROFS)
499 bb_perror_msg(bb_path_mtab_file);
501 if (ENABLE_FEATURE_CLEAN_UP) {
502 for (i = 0; i < count; i++) {
503 free(entries[i].mnt_fsname);
504 free(entries[i].mnt_dir);
505 free(entries[i].mnt_type);
506 free(entries[i].mnt_opts);
513 #if ENABLE_FEATURE_MOUNT_VERBOSE
514 static int verbose_mount(const char *source, const char *target,
515 const char *filesystemtype,
516 unsigned long mountflags, const void *data)
521 rc = mount(source, target, filesystemtype, mountflags, data);
523 bb_perror_msg("mount('%s','%s','%s',0x%08lx,'%s'):%d",
524 source, target, filesystemtype,
525 mountflags, (char*)data, rc);
529 #define verbose_mount(...) mount(__VA_ARGS__)
532 // Append mount options to string
533 static void append_mount_options(char **oldopts, const char *newopts)
535 if (*oldopts && **oldopts) {
536 // Do not insert options which are already there
539 int len = strlen(newopts);
540 p = strchr(newopts, ',');
541 if (p) len = p - newopts;
544 if (!strncmp(p, newopts, len)
545 && (p[len] == ',' || p[len] == '\0'))
551 p = xasprintf("%s,%.*s", *oldopts, len, newopts);
556 while (newopts[0] == ',') newopts++;
559 if (ENABLE_FEATURE_CLEAN_UP) free(*oldopts);
560 *oldopts = xstrdup(newopts);
564 // Use the mount_options list to parse options into flags.
565 // Also update list of unrecognized options if unrecognized != NULL
566 static unsigned long parse_mount_options(char *options, char **unrecognized)
568 unsigned long flags = MS_SILENT;
570 // Loop through options
573 char *comma = strchr(options, ',');
574 const char *option_str = mount_option_str;
576 if (comma) *comma = '\0';
578 // FIXME: use hasmntopt()
579 // Find this option in mount_options
580 for (i = 0; i < ARRAY_SIZE(mount_options); i++) {
581 unsigned opt_len = strlen(option_str);
583 if (strncasecmp(option_str, options, opt_len) == 0
584 && (options[opt_len] == '\0'
585 /* or is it "comment=" thingy in fstab? */
586 IF_FEATURE_MOUNT_FSTAB(IF_DESKTOP( || option_str[opt_len-1] == '=' ))
589 unsigned long fl = mount_options[i];
590 if (fl & BB_MS_INVERTED_VALUE)
596 option_str += opt_len + 1;
598 // We did not recognize this option.
599 // If "unrecognized" is not NULL, append option there.
600 // Note that we should not append *empty* option -
601 // in this case we want to pass NULL, not "", to "data"
602 // parameter of mount(2) syscall.
603 // This is crucial for filesystems that don't accept
604 // any arbitrary mount options, like cgroup fs:
605 // "mount -t cgroup none /mnt"
606 if (options[0] && unrecognized) {
607 // Add it to strflags, to pass on to kernel
608 char *p = *unrecognized;
609 unsigned len = p ? strlen(p) : 0;
610 *unrecognized = p = xrealloc(p, len + strlen(options) + 2);
612 // Comma separated if it's not the first one
613 if (len) p[len++] = ',';
614 strcpy(p + len, options);
619 // Advance to next option
627 // Return a list of all block device backed filesystems
628 static llist_t *get_block_backed_filesystems(void)
630 static const char filesystems[2][sizeof("/proc/filesystems")] = {
635 llist_t *list = NULL;
639 for (i = 0; i < 2; i++) {
640 f = fopen_for_read(filesystems[i]);
643 while ((buf = xmalloc_fgetline(f)) != NULL) {
644 if (is_prefixed_with(buf, "nodev") && isspace(buf[5]))
646 fs = skip_whitespace(buf);
647 if (*fs == '#' || *fs == '*' || !*fs)
650 llist_add_to_end(&list, xstrdup(fs));
654 if (ENABLE_FEATURE_CLEAN_UP) fclose(f);
660 #if ENABLE_FEATURE_CLEAN_UP
661 static void delete_block_backed_filesystems(void)
663 llist_free(fslist, free);
666 void delete_block_backed_filesystems(void);
669 // Perform actual mount of specific filesystem at specific location.
670 // NB: mp->xxx fields may be trashed on exit
671 static int mount_it_now(struct mntent *mp, unsigned long vfsflags, char *filteropts)
677 bb_error_msg("would do mount('%s','%s','%s',0x%08lx,'%s')",
678 mp->mnt_fsname, mp->mnt_dir, mp->mnt_type,
679 vfsflags, filteropts);
683 // Mount, with fallback to read-only if necessary.
686 rc = verbose_mount(mp->mnt_fsname, mp->mnt_dir, mp->mnt_type,
687 vfsflags, filteropts);
689 // If mount failed, try
690 // helper program mount.<mnt_type>
691 if (HELPERS_ALLOWED && rc && mp->mnt_type) {
693 int errno_save = errno;
694 args[0] = xasprintf("mount.%s", mp->mnt_type);
697 args[rc++] = (char *)"-f";
698 if (ENABLE_FEATURE_MTAB_SUPPORT && !USE_MTAB)
699 args[rc++] = (char *)"-n";
700 args[rc++] = mp->mnt_fsname;
701 args[rc++] = mp->mnt_dir;
703 args[rc++] = (char *)"-o";
704 args[rc++] = filteropts;
707 rc = spawn_and_wait(args);
714 if (!rc || (vfsflags & MS_RDONLY) || (errno != EACCES && errno != EROFS))
716 if (!(vfsflags & MS_SILENT))
717 bb_error_msg("%s is write-protected, mounting read-only",
719 vfsflags |= MS_RDONLY;
722 // Abort entirely if permission denied.
724 if (rc && errno == EPERM)
725 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
727 // If the mount was successful, and we're maintaining an old-style
728 // mtab file by hand, add the new entry to it now.
730 if (USE_MTAB && !rc && !(vfsflags & MS_REMOUNT)) {
732 FILE *mountTable = setmntent(bb_path_mtab_file, "a+");
733 const char *option_str = mount_option_str;
737 bb_perror_msg(bb_path_mtab_file);
741 // Add vfs string flags
742 for (i = 0; mount_options[i] != MS_REMOUNT; i++) {
743 if (mount_options[i] > 0 && (mount_options[i] & vfsflags))
744 append_mount_options(&(mp->mnt_opts), option_str);
745 option_str += strlen(option_str) + 1;
748 // Remove trailing / (if any) from directory we mounted on
749 i = strlen(mp->mnt_dir) - 1;
750 while (i > 0 && mp->mnt_dir[i] == '/')
751 mp->mnt_dir[i--] = '\0';
753 // Convert to canonical pathnames as needed
754 mp->mnt_dir = bb_simplify_path(mp->mnt_dir);
756 if (!mp->mnt_type || !*mp->mnt_type) { // bind mount
757 mp->mnt_fsname = fsname = bb_simplify_path(mp->mnt_fsname);
758 mp->mnt_type = (char*)"bind";
760 mp->mnt_freq = mp->mnt_passno = 0;
763 #if ENABLE_FEATURE_MTAB_SUPPORT
764 if (vfsflags & MS_MOVE)
765 update_mtab_entry_on_move(mp);
768 addmntent(mountTable, mp);
769 endmntent(mountTable);
771 if (ENABLE_FEATURE_CLEAN_UP) {
780 #if ENABLE_FEATURE_MOUNT_NFS
784 * Copyright (C) 1993 Rick Sladkey <jrs@world.std.com>
786 * Licensed under GPLv2, see file LICENSE in this source tree.
788 * Wed Feb 8 12:51:48 1995, biro@yggdrasil.com (Ross Biro): allow all port
789 * numbers to be specified on the command line.
791 * Fri, 8 Mar 1996 18:01:39, Swen Thuemmler <swen@uni-paderborn.de>:
792 * Omit the call to connect() for Linux version 1.3.11 or later.
794 * Wed Oct 1 23:55:28 1997: Dick Streefland <dick_streefland@tasking.com>
795 * Implemented the "bg", "fg" and "retry" mount options for NFS.
797 * 1999-02-22 Arkadiusz Mickiewicz <misiek@misiek.eu.org>
798 * - added Native Language Support
800 * Modified by Olaf Kirch and Trond Myklebust for new NFS code,
804 #define MOUNTPORT 635
805 #define MNTPATHLEN 1024
806 #define MNTNAMLEN 255
810 typedef char fhandle[FHSIZE];
813 unsigned int fhandle3_len;
825 MNT3ERR_NAMETOOLONG = 63,
826 MNT3ERR_NOTSUPP = 10004,
827 MNT3ERR_SERVERFAULT = 10006,
829 typedef enum mountstat3 mountstat3;
832 unsigned int fhs_status;
837 typedef struct fhstatus fhstatus;
839 struct mountres3_ok {
842 unsigned int auth_flavours_len;
843 char *auth_flavours_val;
846 typedef struct mountres3_ok mountres3_ok;
849 mountstat3 fhs_status;
851 mountres3_ok mountinfo;
854 typedef struct mountres3 mountres3;
856 typedef char *dirpath;
860 typedef struct mountbody *mountlist;
864 dirpath ml_directory;
867 typedef struct mountbody mountbody;
869 typedef struct groupnode *groups;
875 typedef struct groupnode groupnode;
877 typedef struct exportnode *exports;
884 typedef struct exportnode exportnode;
897 typedef struct ppathcnf ppathcnf;
899 #define MOUNTPROG 100005
902 #define MOUNTPROC_NULL 0
903 #define MOUNTPROC_MNT 1
904 #define MOUNTPROC_DUMP 2
905 #define MOUNTPROC_UMNT 3
906 #define MOUNTPROC_UMNTALL 4
907 #define MOUNTPROC_EXPORT 5
908 #define MOUNTPROC_EXPORTALL 6
910 #define MOUNTVERS_POSIX 2
912 #define MOUNTPROC_PATHCONF 7
916 #define MOUNTPROC3_NULL 0
917 #define MOUNTPROC3_MNT 1
918 #define MOUNTPROC3_DUMP 2
919 #define MOUNTPROC3_UMNT 3
920 #define MOUNTPROC3_UMNTALL 4
921 #define MOUNTPROC3_EXPORT 5
933 * We want to be able to compile mount on old kernels in such a way
934 * that the binary will work well on more recent kernels.
935 * Thus, if necessary we teach nfsmount.c the structure of new fields
936 * that will come later.
938 * Moreover, the new kernel includes conflict with glibc includes
939 * so it is easiest to ignore the kernel altogether (at compile time).
947 unsigned char data[64];
950 struct nfs_mount_data {
953 struct nfs2_fh old_root; /* 1 */
959 int acregmin; /* 1 */
960 int acregmax; /* 1 */
961 int acdirmin; /* 1 */
962 int acdirmax; /* 1 */
963 struct sockaddr_in addr; /* 1 */
964 char hostname[256]; /* 1 */
966 unsigned int bsize; /* 3 */
967 struct nfs3_fh root; /* 4 */
970 /* bits in the flags field */
972 NFS_MOUNT_SOFT = 0x0001, /* 1 */
973 NFS_MOUNT_INTR = 0x0002, /* 1 */
974 NFS_MOUNT_SECURE = 0x0004, /* 1 */
975 NFS_MOUNT_POSIX = 0x0008, /* 1 */
976 NFS_MOUNT_NOCTO = 0x0010, /* 1 */
977 NFS_MOUNT_NOAC = 0x0020, /* 1 */
978 NFS_MOUNT_TCP = 0x0040, /* 2 */
979 NFS_MOUNT_VER3 = 0x0080, /* 3 */
980 NFS_MOUNT_KERBEROS = 0x0100, /* 3 */
981 NFS_MOUNT_NONLM = 0x0200, /* 3 */
982 NFS_MOUNT_NOACL = 0x0800, /* 4 */
983 NFS_MOUNT_NORDIRPLUS = 0x4000
988 * We need to translate between nfs status return values and
989 * the local errno values which may not be the same.
991 * Andreas Schwab <schwab@LS5.informatik.uni-dortmund.de>: change errno:
992 * "after #include <errno.h> the symbol errno is reserved for any use,
993 * it cannot even be used as a struct tag or field name".
996 # define EDQUOT ENOSPC
998 /* Convert each NFSERR_BLAH into EBLAH */
999 static const uint8_t nfs_err_stat[] = {
1001 19, 20, 21, 22, 27, 28,
1002 30, 63, 66, 69, 70, 71
1005 EPERM | ENOENT | EIO | ENXIO | EACCES| EEXIST | \
1006 ENODEV| ENOTDIR | EISDIR | EINVAL| EFBIG | ENOSPC | \
1007 EROFS | ENAMETOOLONG| ENOTEMPTY| EDQUOT| ESTALE| EREMOTE) < 256
1008 typedef uint8_t nfs_err_type;
1010 typedef uint16_t nfs_err_type;
1012 static const nfs_err_type nfs_err_errnum[] = {
1013 EPERM , ENOENT , EIO , ENXIO , EACCES, EEXIST,
1014 ENODEV, ENOTDIR , EISDIR , EINVAL, EFBIG , ENOSPC,
1015 EROFS , ENAMETOOLONG, ENOTEMPTY, EDQUOT, ESTALE, EREMOTE
1017 static char *nfs_strerror(int status)
1021 for (i = 0; i < ARRAY_SIZE(nfs_err_stat); i++) {
1022 if (nfs_err_stat[i] == status)
1023 return strerror(nfs_err_errnum[i]);
1025 return xasprintf("unknown nfs status return value: %d", status);
1028 static bool_t xdr_fhandle(XDR *xdrs, fhandle objp)
1030 return xdr_opaque(xdrs, objp, FHSIZE);
1033 static bool_t xdr_fhstatus(XDR *xdrs, fhstatus *objp)
1035 if (!xdr_u_int(xdrs, &objp->fhs_status))
1037 if (objp->fhs_status == 0)
1038 return xdr_fhandle(xdrs, objp->fhstatus_u.fhs_fhandle);
1042 static bool_t xdr_dirpath(XDR *xdrs, dirpath *objp)
1044 return xdr_string(xdrs, objp, MNTPATHLEN);
1047 static bool_t xdr_fhandle3(XDR *xdrs, fhandle3 *objp)
1049 return xdr_bytes(xdrs, (char **)&objp->fhandle3_val,
1050 (unsigned int *) &objp->fhandle3_len,
1054 static bool_t xdr_mountres3_ok(XDR *xdrs, mountres3_ok *objp)
1056 if (!xdr_fhandle3(xdrs, &objp->fhandle))
1058 return xdr_array(xdrs, &(objp->auth_flavours.auth_flavours_val),
1059 &(objp->auth_flavours.auth_flavours_len),
1062 (xdrproc_t) xdr_int);
1065 static bool_t xdr_mountstat3(XDR *xdrs, mountstat3 *objp)
1067 return xdr_enum(xdrs, (enum_t *) objp);
1070 static bool_t xdr_mountres3(XDR *xdrs, mountres3 *objp)
1072 if (!xdr_mountstat3(xdrs, &objp->fhs_status))
1074 if (objp->fhs_status == MNT_OK)
1075 return xdr_mountres3_ok(xdrs, &objp->mountres3_u.mountinfo);
1079 #define MAX_NFSPROT ((nfs_mount_version >= 4) ? 3 : 2)
1082 * Unfortunately, the kernel prints annoying console messages
1083 * in case of an unexpected nfs mount version (instead of
1084 * just returning some error). Therefore we'll have to try
1085 * and figure out what version the kernel expects.
1088 * KERNEL_NFS_MOUNT_VERSION: kernel sources at compile time
1089 * NFS_MOUNT_VERSION: these nfsmount sources at compile time
1090 * nfs_mount_version: version this source and running kernel can handle
1093 find_kernel_nfs_mount_version(void)
1097 if (nfs_mount_version)
1100 nfs_mount_version = 4; /* default */
1102 kernel_version = get_linux_version_code();
1103 if (kernel_version) {
1104 if (kernel_version < KERNEL_VERSION(2,2,18))
1105 nfs_mount_version = 3;
1106 /* else v4 since 2.3.99pre4 */
1111 get_mountport(struct pmap *pm_mnt,
1112 struct sockaddr_in *server_addr,
1114 long unsigned version,
1115 long unsigned proto,
1118 struct pmaplist *pmap;
1120 server_addr->sin_port = PMAPPORT;
1121 /* glibc 2.4 (still) has pmap_getmaps(struct sockaddr_in *).
1122 * I understand it like "IPv6 for this is not 100% ready" */
1123 pmap = pmap_getmaps(server_addr);
1125 if (version > MAX_NFSPROT)
1126 version = MAX_NFSPROT;
1129 pm_mnt->pm_prog = prog;
1130 pm_mnt->pm_vers = version;
1131 pm_mnt->pm_prot = proto;
1132 pm_mnt->pm_port = port;
1135 if (pmap->pml_map.pm_prog != prog)
1137 if (!version && pm_mnt->pm_vers > pmap->pml_map.pm_vers)
1139 if (version > 2 && pmap->pml_map.pm_vers != version)
1141 if (version && version <= 2 && pmap->pml_map.pm_vers > 2)
1143 if (pmap->pml_map.pm_vers > MAX_NFSPROT
1144 || (proto && pm_mnt->pm_prot && pmap->pml_map.pm_prot != proto)
1145 || (port && pmap->pml_map.pm_port != port)
1149 memcpy(pm_mnt, &pmap->pml_map, sizeof(*pm_mnt));
1151 pmap = pmap->pml_next;
1153 if (!pm_mnt->pm_vers)
1154 pm_mnt->pm_vers = MOUNTVERS;
1155 if (!pm_mnt->pm_port)
1156 pm_mnt->pm_port = MOUNTPORT;
1157 if (!pm_mnt->pm_prot)
1158 pm_mnt->pm_prot = IPPROTO_TCP;
1162 static int daemonize(void)
1165 if (pid < 0) /* error */
1167 if (pid > 0) /* parent */
1171 xopen(bb_dev_null, O_RDWR);
1175 openlog(applet_name, LOG_PID, LOG_DAEMON);
1176 logmode = LOGMODE_SYSLOG;
1180 static inline int daemonize(void) { return -ENOSYS; }
1184 static inline int we_saw_this_host_before(const char *hostname UNUSED_PARAM)
1189 /* RPC strerror analogs are terminally idiotic:
1190 * *mandatory* prefix and \n at end.
1191 * This hopefully helps. Usage:
1192 * error_msg_rpc(clnt_*error*(" ")) */
1193 static void error_msg_rpc(const char *msg)
1196 while (msg[0] == ' ' || msg[0] == ':') msg++;
1198 while (len && msg[len-1] == '\n') len--;
1199 bb_error_msg("%.*s", len, msg);
1202 /* NB: mp->xxx fields may be trashed on exit */
1203 static NOINLINE int nfsmount(struct mntent *mp, unsigned long vfsflags, char *filteropts)
1209 /* prior to 2.6.23, kernel took NFS options in a form of this struct
1210 * only. 2.6.23+ looks at data->version, and if it's not 1..6,
1211 * then data pointer is interpreted as a string. */
1212 struct nfs_mount_data data;
1215 struct sockaddr_in server_addr;
1216 struct sockaddr_in mount_server_addr;
1219 struct fhstatus nfsv2;
1220 struct mountres3 nfsv3;
1238 /* these all are one-bit really. gcc 4.3.1 likes this combination: */
1249 find_kernel_nfs_mount_version();
1257 /* NB: hostname, mounthost, filteropts must be free()d prior to return */
1259 filteropts = xstrdup(filteropts); /* going to trash it later... */
1261 hostname = xstrdup(mp->mnt_fsname);
1262 /* mount_main() guarantees that ':' is there */
1263 s = strchr(hostname, ':');
1266 /* Ignore all but first hostname in replicated mounts
1267 * until they can be fully supported. (mack@sgi.com) */
1268 s = strchr(hostname, ',');
1271 bb_error_msg("warning: multiple hostnames not supported");
1274 server_addr.sin_family = AF_INET;
1275 if (!inet_aton(hostname, &server_addr.sin_addr)) {
1276 hp = gethostbyname(hostname);
1278 bb_herror_msg("%s", hostname);
1281 if (hp->h_length != (int)sizeof(struct in_addr)) {
1282 bb_error_msg_and_die("only IPv4 is supported");
1284 memcpy(&server_addr.sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
1287 memcpy(&mount_server_addr, &server_addr, sizeof(mount_server_addr));
1289 /* add IP address to mtab options for use when unmounting */
1291 if (!mp->mnt_opts) { /* TODO: actually mp->mnt_opts is never NULL */
1292 mp->mnt_opts = xasprintf("addr=%s", inet_ntoa(server_addr.sin_addr));
1294 char *tmp = xasprintf("%s%saddr=%s", mp->mnt_opts,
1295 mp->mnt_opts[0] ? "," : "",
1296 inet_ntoa(server_addr.sin_addr));
1301 /* Set default options.
1302 * rsize/wsize (and bsize, for ver >= 3) are left 0 in order to
1303 * let the kernel decide.
1304 * timeo is filled in after we know whether it'll be TCP or UDP. */
1305 memset(&data, 0, sizeof(data));
1311 data.namlen = NAME_MAX;
1321 retry = 10000; /* 10000 minutes ~ 1 week */
1322 tcp = 1; /* nfs-utils uses tcp per default */
1324 mountprog = MOUNTPROG;
1332 if (filteropts) for (opt = strtok(filteropts, ","); opt; opt = strtok(NULL, ",")) {
1333 char *opteq = strchr(opt, '=');
1336 static const char options[] ALIGN1 =
1341 /* 4 */ "acregmin\0"
1342 /* 5 */ "acregmax\0"
1343 /* 6 */ "acdirmin\0"
1344 /* 7 */ "acdirmax\0"
1348 /* 11 */ "mountport\0"
1349 /* 12 */ "mounthost\0"
1350 /* 13 */ "mountprog\0"
1351 /* 14 */ "mountvers\0"
1352 /* 15 */ "nfsprog\0"
1353 /* 16 */ "nfsvers\0"
1360 idx = index_in_strings(options, opt);
1362 case 12: // "mounthost"
1363 mounthost = xstrndup(opteq,
1364 strcspn(opteq, " \t\n\r,"));
1367 if (is_prefixed_with(opteq, "tcp"))
1369 else if (is_prefixed_with(opteq, "udp"))
1372 bb_error_msg("warning: unrecognized proto= option");
1374 case 20: // "addr" - ignore
1377 if (vfsflags & MS_REMOUNT)
1381 val = xatoi_positive(opteq);
1392 case 3: // "retrans"
1395 case 4: // "acregmin"
1396 data.acregmin = val;
1398 case 5: // "acregmax"
1399 data.acregmax = val;
1401 case 6: // "acdirmin"
1402 data.acdirmin = val;
1404 case 7: // "acdirmax"
1405 data.acdirmax = val;
1407 case 8: // "actimeo"
1408 data.acregmin = val;
1409 data.acregmax = val;
1410 data.acdirmin = val;
1411 data.acdirmax = val;
1419 case 11: // "mountport"
1422 case 13: // "mountprog"
1425 case 14: // "mountvers"
1428 case 15: // "nfsprog"
1431 case 16: // "nfsvers"
1435 case 19: // "namlen"
1436 //if (nfs_mount_version >= 2)
1439 // bb_error_msg("warning: option namlen is not supported\n");
1442 bb_error_msg("unknown nfs mount parameter: %s=%d", opt, val);
1446 else { /* not of the form opt=val */
1447 static const char options[] ALIGN1 =
1462 if (is_prefixed_with(opt, "no")) {
1466 switch (index_in_strings(options, opt)) {
1502 if (nfs_mount_version >= 3)
1505 bb_error_msg("warning: option nolock is not supported");
1514 bb_error_msg("unknown nfs mount option: %s%s", val ? "" : "no", opt);
1519 proto = (tcp) ? IPPROTO_TCP : IPPROTO_UDP;
1521 data.flags = (soft ? NFS_MOUNT_SOFT : 0)
1522 | (intr ? NFS_MOUNT_INTR : 0)
1523 | (posix ? NFS_MOUNT_POSIX : 0)
1524 | (nocto ? NFS_MOUNT_NOCTO : 0)
1525 | (noac ? NFS_MOUNT_NOAC : 0)
1526 | (nordirplus ? NFS_MOUNT_NORDIRPLUS : 0)
1527 | (noacl ? NFS_MOUNT_NOACL : 0);
1528 if (nfs_mount_version >= 2)
1529 data.flags |= (tcp ? NFS_MOUNT_TCP : 0);
1530 if (nfs_mount_version >= 3)
1531 data.flags |= (nolock ? NFS_MOUNT_NONLM : 0);
1532 if (nfsvers > MAX_NFSPROT || mountvers > MAX_NFSPROT) {
1533 bb_error_msg("NFSv%d not supported", nfsvers);
1536 if (nfsvers && !mountvers)
1537 mountvers = (nfsvers < 3) ? 1 : nfsvers;
1538 if (nfsvers && nfsvers < mountvers) {
1539 mountvers = nfsvers;
1542 /* Adjust options if none specified */
1544 data.timeo = tcp ? 70 : 7;
1546 data.version = nfs_mount_version;
1548 if (vfsflags & MS_REMOUNT)
1552 * If the previous mount operation on the same host was
1553 * backgrounded, and the "bg" for this mount is also set,
1554 * give up immediately, to avoid the initial timeout.
1556 if (bg && we_saw_this_host_before(hostname)) {
1557 daemonized = daemonize();
1558 if (daemonized <= 0) { /* parent or error */
1559 retval = -daemonized;
1564 /* Create mount daemon client */
1565 /* See if the nfs host = mount host. */
1567 if (mounthost[0] >= '0' && mounthost[0] <= '9') {
1568 mount_server_addr.sin_family = AF_INET;
1569 mount_server_addr.sin_addr.s_addr = inet_addr(hostname);
1571 hp = gethostbyname(mounthost);
1573 bb_herror_msg("%s", mounthost);
1576 if (hp->h_length != (int)sizeof(struct in_addr)) {
1577 bb_error_msg_and_die("only IPv4 is supported");
1579 mount_server_addr.sin_family = AF_INET;
1580 memcpy(&mount_server_addr.sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
1585 * The following loop implements the mount retries. When the mount
1586 * times out, and the "bg" option is set, we background ourself
1587 * and continue trying.
1589 * The case where the mount point is not present and the "bg"
1590 * option is set, is treated as a timeout. This is done to
1591 * support nested mounts.
1593 * The "retry" count specified by the user is the number of
1594 * minutes to retry before giving up.
1597 struct timeval total_timeout;
1598 struct timeval retry_timeout;
1604 retry_timeout.tv_sec = 3;
1605 retry_timeout.tv_usec = 0;
1606 total_timeout.tv_sec = 20;
1607 total_timeout.tv_usec = 0;
1608 /* FIXME: use monotonic()? */
1609 timeout = time(NULL) + 60 * retry;
1613 /* Be careful not to use too many CPU cycles */
1617 get_mountport(&pm_mnt, &mount_server_addr,
1622 nfsvers = (pm_mnt.pm_vers < 2) ? 2 : pm_mnt.pm_vers;
1624 /* contact the mount daemon via TCP */
1625 mount_server_addr.sin_port = htons(pm_mnt.pm_port);
1626 msock = RPC_ANYSOCK;
1628 switch (pm_mnt.pm_prot) {
1630 mclient = clntudp_create(&mount_server_addr,
1637 mount_server_addr.sin_port = htons(pm_mnt.pm_port);
1638 msock = RPC_ANYSOCK;
1640 mclient = clnttcp_create(&mount_server_addr,
1649 if (!daemonized && prevt == 0)
1650 error_msg_rpc(clnt_spcreateerror(" "));
1652 enum clnt_stat clnt_stat;
1654 /* Try to mount hostname:pathname */
1655 mclient->cl_auth = authunix_create_default();
1657 /* Make pointers in xdr_mountres3 NULL so
1658 * that xdr_array allocates memory for us
1660 memset(&status, 0, sizeof(status));
1662 if (pm_mnt.pm_vers == 3)
1663 clnt_stat = clnt_call(mclient, MOUNTPROC3_MNT,
1664 (xdrproc_t) xdr_dirpath,
1665 (caddr_t) &pathname,
1666 (xdrproc_t) xdr_mountres3,
1670 clnt_stat = clnt_call(mclient, MOUNTPROC_MNT,
1671 (xdrproc_t) xdr_dirpath,
1672 (caddr_t) &pathname,
1673 (xdrproc_t) xdr_fhstatus,
1677 if (clnt_stat == RPC_SUCCESS)
1678 goto prepare_kernel_data; /* we're done */
1679 if (errno != ECONNREFUSED) {
1680 error_msg_rpc(clnt_sperror(mclient, " "));
1681 goto fail; /* don't retry */
1683 /* Connection refused */
1684 if (!daemonized && prevt == 0) /* print just once */
1685 error_msg_rpc(clnt_sperror(mclient, " "));
1686 auth_destroy(mclient->cl_auth);
1687 clnt_destroy(mclient);
1693 /* Timeout. We are going to retry... maybe */
1697 daemonized = daemonize();
1698 if (daemonized <= 0) { /* parent or error */
1699 retval = -daemonized;
1706 /* TODO error message */
1712 prepare_kernel_data:
1715 if (status.nfsv2.fhs_status != 0) {
1716 bb_error_msg("%s:%s failed, reason given by server: %s",
1718 nfs_strerror(status.nfsv2.fhs_status));
1721 memcpy(data.root.data,
1722 (char *) status.nfsv2.fhstatus_u.fhs_fhandle,
1724 data.root.size = NFS_FHSIZE;
1725 memcpy(data.old_root.data,
1726 (char *) status.nfsv2.fhstatus_u.fhs_fhandle,
1729 fhandle3 *my_fhandle;
1730 if (status.nfsv3.fhs_status != 0) {
1731 bb_error_msg("%s:%s failed, reason given by server: %s",
1733 nfs_strerror(status.nfsv3.fhs_status));
1736 my_fhandle = &status.nfsv3.mountres3_u.mountinfo.fhandle;
1737 memset(data.old_root.data, 0, NFS_FHSIZE);
1738 memset(&data.root, 0, sizeof(data.root));
1739 data.root.size = my_fhandle->fhandle3_len;
1740 memcpy(data.root.data,
1741 (char *) my_fhandle->fhandle3_val,
1742 my_fhandle->fhandle3_len);
1744 data.flags |= NFS_MOUNT_VER3;
1747 /* Create nfs socket for kernel */
1749 if (nfs_mount_version < 3) {
1750 bb_error_msg("NFS over TCP is not supported");
1753 fsock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
1755 fsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
1757 bb_perror_msg("nfs socket");
1760 if (bindresvport(fsock, 0) < 0) {
1761 bb_perror_msg("nfs bindresvport");
1765 server_addr.sin_port = PMAPPORT;
1766 port = pmap_getport(&server_addr, nfsprog, nfsvers,
1767 tcp ? IPPROTO_TCP : IPPROTO_UDP);
1771 server_addr.sin_port = htons(port);
1773 /* Prepare data structure for kernel */
1775 memcpy((char *) &data.addr, (char *) &server_addr, sizeof(data.addr));
1776 strncpy(data.hostname, hostname, sizeof(data.hostname));
1779 auth_destroy(mclient->cl_auth);
1780 clnt_destroy(mclient);
1785 /* We must wait until mount directory is available */
1786 struct stat statbuf;
1788 while (stat(mp->mnt_dir, &statbuf) == -1) {
1790 daemonized = daemonize();
1791 if (daemonized <= 0) { /* parent or error */
1792 /* FIXME: parent doesn't close fsock - ??! */
1793 retval = -daemonized;
1797 sleep(delay); /* 1, 2, 4, 8, 16, 30, ... */
1804 /* Perform actual mount */
1806 retval = mount_it_now(mp, vfsflags, (char*)&data);
1813 auth_destroy(mclient->cl_auth);
1814 clnt_destroy(mclient);
1828 #else // !ENABLE_FEATURE_MOUNT_NFS
1830 /* Linux 2.6.23+ supports nfs mounts with options passed as a string.
1831 * For older kernels, you must build busybox with ENABLE_FEATURE_MOUNT_NFS.
1832 * (However, note that then you lose any chances that NFS over IPv6 would work).
1834 static int nfsmount(struct mntent *mp, unsigned long vfsflags, char *filteropts)
1836 len_and_sockaddr *lsa;
1842 # if ENABLE_FEATURE_IPV6
1843 end = strchr(mp->mnt_fsname, ']');
1844 if (end && end[1] == ':')
1848 /* mount_main() guarantees that ':' is there */
1849 end = strchr(mp->mnt_fsname, ':');
1852 lsa = xhost2sockaddr(mp->mnt_fsname, /*port:*/ 0);
1854 dotted = xmalloc_sockaddr2dotted_noport(&lsa->u.sa);
1855 if (ENABLE_FEATURE_CLEAN_UP) free(lsa);
1856 opts = xasprintf("%s%saddr=%s",
1857 filteropts ? filteropts : "",
1858 filteropts ? "," : "",
1861 if (ENABLE_FEATURE_CLEAN_UP) free(dotted);
1862 ret = mount_it_now(mp, vfsflags, opts);
1863 if (ENABLE_FEATURE_CLEAN_UP) free(opts);
1868 #endif // !ENABLE_FEATURE_MOUNT_NFS
1870 // Mount one directory. Handles CIFS, NFS, loopback, autobind, and filesystem
1871 // type detection. Returns 0 for success, nonzero for failure.
1872 // NB: mp->xxx fields may be trashed on exit
1873 static int singlemount(struct mntent *mp, int ignore_busy)
1876 unsigned long vfsflags;
1877 char *loopFile = NULL, *filteropts = NULL;
1883 vfsflags = parse_mount_options(mp->mnt_opts, &filteropts);
1885 // Treat fstype "auto" as unspecified
1886 if (mp->mnt_type && strcmp(mp->mnt_type, "auto") == 0)
1887 mp->mnt_type = NULL;
1889 // Might this be a virtual filesystem?
1890 if (ENABLE_FEATURE_MOUNT_HELPERS && strchr(mp->mnt_fsname, '#')) {
1894 // fsname: "cmd#arg1#arg2..."
1895 // WARNING: allows execution of arbitrary commands!
1896 // Try "mount 'sh#-c#sh' bogus_dir".
1897 // It is safe ONLY because non-root
1898 // cannot use two-argument mount command
1899 // and using one-argument "mount 'sh#-c#sh'" doesn't work:
1900 // "mount: can't find sh#-c#sh in /etc/fstab"
1901 // (if /etc/fstab has it, it's ok: root sets up /etc/fstab).
1906 while (*s && n < 35 - 2) {
1907 if (*s++ == '#' && *s != '#') {
1912 args[n++] = mp->mnt_dir;
1914 rc = spawn_and_wait(args);
1918 // Might this be an CIFS filesystem?
1919 if (ENABLE_FEATURE_MOUNT_CIFS
1920 && (!mp->mnt_type || strcmp(mp->mnt_type, "cifs") == 0)
1921 && (mp->mnt_fsname[0] == '/' || mp->mnt_fsname[0] == '\\')
1922 && mp->mnt_fsname[0] == mp->mnt_fsname[1]
1926 char *hostname, *share;
1928 len_and_sockaddr *lsa;
1930 // Parse mp->mnt_fsname of the form "//hostname/share[/dir1/dir2]"
1932 hostname = mp->mnt_fsname + 2;
1933 len = strcspn(hostname, "/\\");
1934 share = hostname + len + 1;
1935 if (len == 0 // 3rd char is a [back]slash (IOW: empty hostname)
1936 || share[-1] == '\0' // no [back]slash after hostname
1937 || share[0] == '\0' // empty share name
1943 len = strcspn(share, "/\\");
1945 // "unc=\\hostname\share" option is mandatory
1946 // after CIFS option parsing was rewritten in Linux 3.4.
1947 // Must use backslashes.
1948 // If /dir1/dir2 is present, also add "prefixpath=dir1/dir2"
1950 char *unc = xasprintf(
1951 share[len] != '\0' /* "/dir1/dir2" exists? */
1952 ? "unc=\\\\%s\\%.*s,prefixpath=%s"
1953 : "unc=\\\\%s\\%.*s",
1956 share + len + 1 /* "dir1/dir2" */
1958 parse_mount_options(unc, &filteropts);
1959 if (ENABLE_FEATURE_CLEAN_UP) free(unc);
1962 lsa = host2sockaddr(hostname, 0);
1967 // Insert "ip=..." option into options
1968 dotted = xmalloc_sockaddr2dotted_noport(&lsa->u.sa);
1969 if (ENABLE_FEATURE_CLEAN_UP) free(lsa);
1970 ip = xasprintf("ip=%s", dotted);
1971 if (ENABLE_FEATURE_CLEAN_UP) free(dotted);
1972 parse_mount_options(ip, &filteropts);
1973 if (ENABLE_FEATURE_CLEAN_UP) free(ip);
1975 mp->mnt_type = (char*)"cifs";
1976 rc = mount_it_now(mp, vfsflags, filteropts);
1981 // Might this be an NFS filesystem?
1982 if ((!mp->mnt_type || is_prefixed_with(mp->mnt_type, "nfs"))
1983 && strchr(mp->mnt_fsname, ':') != NULL
1986 mp->mnt_type = (char*)"nfs";
1987 rc = nfsmount(mp, vfsflags, filteropts);
1991 // Look at the file. (Not found isn't a failure for remount, or for
1992 // a synthetic filesystem like proc or sysfs.)
1993 // (We use stat, not lstat, in order to allow
1994 // mount symlink_to_file_or_blkdev dir)
1995 if (!stat(mp->mnt_fsname, &st)
1996 && !(vfsflags & (MS_REMOUNT | MS_BIND | MS_MOVE))
1998 // Do we need to allocate a loopback device for it?
1999 if (ENABLE_FEATURE_MOUNT_LOOP && S_ISREG(st.st_mode)) {
2000 loopFile = bb_simplify_path(mp->mnt_fsname);
2001 mp->mnt_fsname = NULL; // will receive malloced loop dev name
2002 if (set_loop(&mp->mnt_fsname, loopFile, 0, /*ro:*/ (vfsflags & MS_RDONLY)) < 0) {
2003 if (errno == EPERM || errno == EACCES)
2004 bb_error_msg(bb_msg_perm_denied_are_you_root);
2006 bb_perror_msg("can't setup loop device");
2010 // Autodetect bind mounts
2011 } else if (S_ISDIR(st.st_mode) && !mp->mnt_type)
2012 vfsflags |= MS_BIND;
2015 // If we know the fstype (or don't need to), jump straight
2016 // to the actual mount.
2017 if (mp->mnt_type || (vfsflags & (MS_REMOUNT | MS_BIND | MS_MOVE))) {
2020 next = mp->mnt_type ? strchr(mp->mnt_type, ',') : NULL;
2023 rc = mount_it_now(mp, vfsflags, filteropts);
2024 if (rc == 0 || !next)
2026 mp->mnt_type = next + 1;
2029 // Loop through filesystem types until mount succeeds
2032 // Initialize list of block backed filesystems.
2033 // This has to be done here so that during "mount -a",
2034 // mounts after /proc shows up can autodetect.
2036 fslist = get_block_backed_filesystems();
2037 if (ENABLE_FEATURE_CLEAN_UP && fslist)
2038 atexit(delete_block_backed_filesystems);
2041 for (fl = fslist; fl; fl = fl->link) {
2042 mp->mnt_type = fl->data;
2043 rc = mount_it_now(mp, vfsflags, filteropts);
2049 // If mount failed, clean up loop file (if any).
2050 if (ENABLE_FEATURE_MOUNT_LOOP && rc && loopFile) {
2051 del_loop(mp->mnt_fsname);
2052 if (ENABLE_FEATURE_CLEAN_UP) {
2054 free(mp->mnt_fsname);
2059 if (ENABLE_FEATURE_CLEAN_UP)
2062 if (errno == EBUSY && ignore_busy)
2065 bb_perror_msg("mounting %s on %s failed", mp->mnt_fsname, mp->mnt_dir);
2070 // -O interprets a list of filter options which select whether a mount
2071 // point will be mounted: only mounts with options matching *all* filtering
2072 // options will be selected.
2073 // By default each -O filter option must be present in the list of mount
2074 // options, but if it is prefixed by "no" then it must be absent.
2076 // -O a,nob,c matches -o a,c but fails to match -o a,b,c
2077 // (and also fails to match -o a because -o c is absent).
2079 // It is different from -t in that each option is matched exactly; a leading
2080 // "no" at the beginning of one option does not negate the rest.
2081 static int match_opt(const char *fs_opt_in, const char *O_opt)
2087 const char *fs_opt = fs_opt_in;
2091 // If option begins with "no" then treat as an inverted match:
2092 // matching is a failure
2094 if (O_opt[0] == 'n' && O_opt[1] == 'o') {
2098 // Isolate the current O option
2099 O_len = strchrnul(O_opt, ',') - O_opt;
2100 // Check for a match against existing options
2102 if (strncmp(fs_opt, O_opt, O_len) == 0
2103 && (fs_opt[O_len] == '\0' || fs_opt[O_len] == ',')
2106 return 0; // "no" prefix, but option found
2107 match = 1; // current O option found, go check next one
2110 fs_opt = strchr(fs_opt, ',');
2116 return 0; // match wanted but not found
2117 if (O_opt[O_len] == '\0') // end?
2119 // Step to the next O option
2122 // If we get here then everything matched
2126 // Parse options, if necessary parse fstab/mtab, and call singlemount for
2127 // each directory to be mounted.
2128 int mount_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2129 int mount_main(int argc UNUSED_PARAM, char **argv)
2131 char *cmdopts = xzalloc(1);
2132 char *fstype = NULL;
2133 char *O_optmatch = NULL;
2135 llist_t *lst_o = NULL;
2136 const char *fstabname = "/etc/fstab";
2139 int rc = EXIT_SUCCESS;
2140 unsigned long cmdopt_flags;
2142 struct mntent mtpair[2], *mtcur = mtpair;
2143 IF_NOT_DESKTOP(const int nonroot = 0;)
2145 IF_DESKTOP(int nonroot = ) sanitize_env_if_suid();
2149 // Parse long options, like --bind and --move. Note that -o option
2150 // and --option are synonymous. Yes, this means --remount,rw works.
2151 for (i = j = 1; argv[i]; i++) {
2152 if (argv[i][0] == '-' && argv[i][1] == '-')
2153 append_mount_options(&cmdopts, argv[i] + 2);
2155 argv[j++] = argv[i];
2159 // Parse remaining options
2160 // Max 2 params; -o is a list, -v is a counter
2161 opt_complementary = "?2o::" IF_FEATURE_MOUNT_VERBOSE("vv");
2162 opt = getopt32(argv, OPTION_STR, &lst_o, &fstype, &O_optmatch
2163 IF_FEATURE_MOUNT_OTHERTAB(, &fstabname)
2164 IF_FEATURE_MOUNT_VERBOSE(, &verbose));
2165 while (lst_o) append_mount_options(&cmdopts, llist_pop(&lst_o)); // -o
2166 if (opt & OPT_r) append_mount_options(&cmdopts, "ro"); // -r
2167 if (opt & OPT_w) append_mount_options(&cmdopts, "rw"); // -w
2170 // If we have no arguments, show currently mounted filesystems
2172 if (!(opt & OPT_a)) {
2173 FILE *mountTable = setmntent(bb_path_mtab_file, "r");
2176 bb_error_msg_and_die("no %s", bb_path_mtab_file);
2178 while (getmntent_r(mountTable, &mtpair[0], getmntent_buf,
2181 // Don't show rootfs. FIXME: why??
2182 // util-linux 2.12a happily shows rootfs...
2183 //if (strcmp(mtpair->mnt_fsname, "rootfs") == 0) continue;
2185 if (!fstype || strcmp(mtpair->mnt_type, fstype) == 0)
2186 printf("%s on %s type %s (%s)\n", mtpair->mnt_fsname,
2187 mtpair->mnt_dir, mtpair->mnt_type,
2190 if (ENABLE_FEATURE_CLEAN_UP)
2191 endmntent(mountTable);
2192 return EXIT_SUCCESS;
2194 storage_path = NULL;
2196 // When we have two arguments, the second is the directory and we can
2197 // skip looking at fstab entirely. We can always abspath() the directory
2198 // argument when we get it.
2201 bb_error_msg_and_die(bb_msg_you_must_be_root);
2202 mtpair->mnt_fsname = argv[0];
2203 mtpair->mnt_dir = argv[1];
2204 mtpair->mnt_type = fstype;
2205 mtpair->mnt_opts = cmdopts;
2206 resolve_mount_spec(&mtpair->mnt_fsname);
2207 rc = singlemount(mtpair, /*ignore_busy:*/ 0);
2210 storage_path = bb_simplify_path(argv[0]); // malloced
2213 // Past this point, we are handling either "mount -a [opts]"
2214 // or "mount [opts] single_param"
2216 cmdopt_flags = parse_mount_options(cmdopts, NULL);
2217 if (nonroot && (cmdopt_flags & ~MS_SILENT)) // Non-root users cannot specify flags
2218 bb_error_msg_and_die(bb_msg_you_must_be_root);
2220 // If we have a shared subtree flag, don't worry about fstab or mtab.
2221 if (ENABLE_FEATURE_MOUNT_FLAGS
2222 && (cmdopt_flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE))
2224 // verbose_mount(source, target, type, flags, data)
2225 rc = verbose_mount("", argv[0], "", cmdopt_flags, "");
2227 bb_simple_perror_msg_and_die(argv[0]);
2231 // A malicious user could overmount /usr without this.
2232 if (ENABLE_FEATURE_MOUNT_OTHERTAB && nonroot)
2233 fstabname = "/etc/fstab";
2234 // Open either fstab or mtab
2235 if (cmdopt_flags & MS_REMOUNT) {
2236 // WARNING. I am not sure this matches util-linux's
2237 // behavior. It's possible util-linux does not
2238 // take -o opts from mtab (takes only mount source).
2239 fstabname = bb_path_mtab_file;
2241 fstab = setmntent(fstabname, "r");
2243 bb_perror_msg_and_die("can't read '%s'", fstabname);
2245 // Loop through entries until we find what we're looking for
2246 memset(mtpair, 0, sizeof(mtpair));
2248 struct mntent *mtother = (mtcur==mtpair ? mtpair+1 : mtpair);
2250 // Get next fstab entry
2251 if (!getmntent_r(fstab, mtcur, getmntent_buf
2252 + (mtcur==mtpair ? GETMNTENT_BUFSIZE/2 : 0),
2253 GETMNTENT_BUFSIZE/2)
2254 ) { // End of fstab/mtab is reached
2255 mtcur = mtother; // the thing we found last time
2259 // If we're trying to mount something specific and this isn't it,
2260 // skip it. Note we must match the exact text in fstab (ala
2261 // "proc") or a full path from root
2264 // Is this what we're looking for?
2265 if (strcmp(argv[0], mtcur->mnt_fsname) != 0
2266 && strcmp(storage_path, mtcur->mnt_fsname) != 0
2267 && strcmp(argv[0], mtcur->mnt_dir) != 0
2268 && strcmp(storage_path, mtcur->mnt_dir) != 0
2273 // Remember this entry. Something later may have
2274 // overmounted it, and we want the _last_ match.
2277 // If we're mounting all
2280 // No, mount -a won't mount anything,
2281 // even user mounts, for mere humans
2283 bb_error_msg_and_die(bb_msg_you_must_be_root);
2285 // Does type match? (NULL matches always)
2286 if (!match_fstype(mtcur, fstype))
2289 // Skip noauto and swap anyway
2290 if ((parse_mount_options(mtcur->mnt_opts, NULL) & (MOUNT_NOAUTO | MOUNT_SWAP))
2291 // swap is bogus "fstype", parse_mount_options can't check fstypes
2292 || strcasecmp(mtcur->mnt_type, "swap") == 0
2297 // Does (at least one) option match?
2298 // (NULL matches always)
2299 if (!match_opt(mtcur->mnt_opts, O_optmatch))
2302 resolve_mount_spec(&mtcur->mnt_fsname);
2304 // NFS mounts want this to be xrealloc-able
2305 mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
2307 // If nothing is mounted on this directory...
2308 // (otherwise repeated "mount -a" mounts everything again)
2309 mp = find_mount_point(mtcur->mnt_dir, /*subdir_too:*/ 0);
2310 // We do not check fsname match of found mount point -
2311 // "/" may have fsname of "/dev/root" while fstab
2312 // says "/dev/something_else".
2315 bb_error_msg("according to %s, "
2316 "%s is already mounted on %s",
2318 mp->mnt_fsname, mp->mnt_dir);
2321 // ...mount this thing
2322 if (singlemount(mtcur, /*ignore_busy:*/ 1)) {
2323 // Count number of failed mounts
2327 free(mtcur->mnt_opts);
2331 // End of fstab/mtab is reached.
2332 // Were we looking for something specific?
2333 if (argv[0]) { // yes
2336 // If we didn't find anything, complain
2337 if (!mtcur->mnt_fsname)
2338 bb_error_msg_and_die("can't find %s in %s",
2339 argv[0], fstabname);
2341 // What happens when we try to "mount swap_partition"?
2342 // (fstab containts "swap_partition swap swap defaults 0 0")
2343 // util-linux-ng 2.13.1 does this:
2344 // stat("/sbin/mount.swap", 0x7fff62a3a350) = -1 ENOENT (No such file or directory)
2345 // mount("swap_partition", "swap", "swap", MS_MGC_VAL, NULL) = -1 ENOENT (No such file or directory)
2346 // lstat("swap", 0x7fff62a3a640) = -1 ENOENT (No such file or directory)
2347 // write(2, "mount: mount point swap does not exist\n", 39) = 39
2348 // exit_group(32) = ?
2350 // In case we want to simply skip swap partitions:
2351 l = parse_mount_options(mtcur->mnt_opts, NULL);
2352 if ((l & MOUNT_SWAP)
2353 // swap is bogus "fstype", parse_mount_options can't check fstypes
2354 || strcasecmp(mtcur->mnt_type, "swap") == 0
2360 // fstab must have "users" or "user"
2361 l = parse_mount_options(mtcur->mnt_opts, NULL);
2362 if (!(l & MOUNT_USERS))
2363 bb_error_msg_and_die(bb_msg_you_must_be_root);
2366 //util-linux-2.12 does not do this check.
2367 //// If nothing is mounted on this directory...
2368 //// (otherwise repeated "mount FOO" mounts FOO again)
2369 //mp = find_mount_point(mtcur->mnt_dir, /*subdir_too:*/ 0);
2371 // bb_error_msg("according to %s, "
2372 // "%s is already mounted on %s",
2373 // bb_path_mtab_file,
2374 // mp->mnt_fsname, mp->mnt_dir);
2376 // ...mount the last thing we found
2377 mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
2378 append_mount_options(&(mtcur->mnt_opts), cmdopts);
2379 resolve_mount_spec(&mtpair->mnt_fsname);
2380 rc = singlemount(mtcur, /*ignore_busy:*/ 0);
2381 if (ENABLE_FEATURE_CLEAN_UP)
2382 free(mtcur->mnt_opts);
2387 if (ENABLE_FEATURE_CLEAN_UP)
2389 if (ENABLE_FEATURE_CLEAN_UP) {
2394 //TODO: exitcode should be ORed mask of (from "man mount"):
2396 // 1 incorrect invocation or permissions
2397 // 2 system error (out of memory, cannot fork, no more loop devices)
2398 // 4 internal mount bug or missing nfs support in mount
2400 //16 problems writing or locking /etc/mtab
2402 //64 some mount succeeded