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busybox/util-linux/mount.c
Roman Borisov 19311bfa7b mount: add --rbind option support 
Signed-off-by: Roman Borisov <ext-roman.borisov@nokia.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-03-26 23:12:12 +01:00

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/* vi: set sw=4 ts=4: */
/*
* Mini mount implementation for busybox
*
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
* Copyright (C) 2005-2006 by Rob Landley <rob@landley.net>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
// Design notes: There is no spec for mount. Remind me to write one.
//
// mount_main() calls singlemount() which calls mount_it_now().
//
// mount_main() can loop through /etc/fstab for mount -a
// singlemount() can loop through /etc/filesystems for fstype detection.
// mount_it_now() does the actual mount.
//
#include <mntent.h>
#include <syslog.h>
#include <sys/mount.h>
// Grab more as needed from util-linux's mount/mount_constants.h
#ifndef MS_DIRSYNC
# define MS_DIRSYNC (1 << 7) // Directory modifications are synchronous
#endif
#ifndef MS_UNION
# define MS_UNION (1 << 8)
#endif
#ifndef MS_BIND
# define MS_BIND (1 << 12)
#endif
#ifndef MS_MOVE
# define MS_MOVE (1 << 13)
#endif
#ifndef MS_RECURSIVE
# define MS_RECURSIVE (1 << 14)
#endif
#ifndef MS_SILENT
# define MS_SILENT (1 << 15)
#endif
// The shared subtree stuff, which went in around 2.6.15
#ifndef MS_UNBINDABLE
# define MS_UNBINDABLE (1 << 17)
#endif
#ifndef MS_PRIVATE
# define MS_PRIVATE (1 << 18)
#endif
#ifndef MS_SLAVE
# define MS_SLAVE (1 << 19)
#endif
#ifndef MS_SHARED
# define MS_SHARED (1 << 20)
#endif
#ifndef MS_RELATIME
# define MS_RELATIME (1 << 21)
#endif
#include "libbb.h"
#if ENABLE_FEATURE_MOUNT_LABEL
# include "volume_id.h"
#else
# define resolve_mount_spec(fsname) ((void)0)
#endif
// Needed for nfs support only
#include <sys/utsname.h>
#undef TRUE
#undef FALSE
#if ENABLE_FEATURE_MOUNT_NFS
/* This is just a warning of a common mistake. Possibly this should be a
* uclibc faq entry rather than in busybox... */
# if defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
# error "You need to build uClibc with UCLIBC_HAS_RPC for NFS support"
# endif
# include <rpc/rpc.h>
# include <rpc/pmap_prot.h>
# include <rpc/pmap_clnt.h>
#endif
#if defined(__dietlibc__)
// 16.12.2006, Sampo Kellomaki (sampo@iki.fi)
// dietlibc-0.30 does not have implementation of getmntent_r()
static struct mntent *getmntent_r(FILE* stream, struct mntent* result,
char* buffer UNUSED_PARAM, int bufsize UNUSED_PARAM)
{
struct mntent* ment = getmntent(stream);
return memcpy(result, ment, sizeof(*ment));
}
#endif
// Not real flags, but we want to be able to check for this.
enum {
MOUNT_USERS = (1 << 28) * ENABLE_DESKTOP,
MOUNT_NOAUTO = (1 << 29),
MOUNT_SWAP = (1 << 30),
};
#define OPTION_STR "o:t:rwanfvsiO:"
enum {
OPT_o = (1 << 0),
OPT_t = (1 << 1),
OPT_r = (1 << 2),
OPT_w = (1 << 3),
OPT_a = (1 << 4),
OPT_n = (1 << 5),
OPT_f = (1 << 6),
OPT_v = (1 << 7),
OPT_s = (1 << 8),
OPT_i = (1 << 9),
OPT_O = (1 << 10),
};
#if ENABLE_FEATURE_MTAB_SUPPORT
#define USE_MTAB (!(option_mask32 & OPT_n))
#else
#define USE_MTAB 0
#endif
#if ENABLE_FEATURE_MOUNT_FAKE
#define FAKE_IT (option_mask32 & OPT_f)
#else
#define FAKE_IT 0
#endif
#if ENABLE_FEATURE_MOUNT_HELPERS
#define HELPERS_ALLOWED (!(option_mask32 & OPT_i))
#else
#define HELPERS_ALLOWED 0
#endif
// TODO: more "user" flag compatibility.
// "user" option (from mount manpage):
// Only the user that mounted a filesystem can unmount it again.
// If any user should be able to unmount, then use users instead of user
// in the fstab line. The owner option is similar to the user option,
// with the restriction that the user must be the owner of the special file.
// This may be useful e.g. for /dev/fd if a login script makes
// the console user owner of this device.
// Standard mount options (from -o options or --options),
// with corresponding flags
static const int32_t mount_options[] = {
// MS_FLAGS set a bit. ~MS_FLAGS disable that bit. 0 flags are NOPs.
IF_FEATURE_MOUNT_LOOP(
/* "loop" */ 0,
)
IF_FEATURE_MOUNT_FSTAB(
/* "defaults" */ 0,
/* "quiet" 0 - do not filter out, vfat wants to see it */
/* "noauto" */ MOUNT_NOAUTO,
/* "sw" */ MOUNT_SWAP,
/* "swap" */ MOUNT_SWAP,
IF_DESKTOP(/* "user" */ MOUNT_USERS,)
IF_DESKTOP(/* "users" */ MOUNT_USERS,)
/* "_netdev" */ 0,
)
IF_FEATURE_MOUNT_FLAGS(
// vfs flags
/* "nosuid" */ MS_NOSUID,
/* "suid" */ ~MS_NOSUID,
/* "dev" */ ~MS_NODEV,
/* "nodev" */ MS_NODEV,
/* "exec" */ ~MS_NOEXEC,
/* "noexec" */ MS_NOEXEC,
/* "sync" */ MS_SYNCHRONOUS,
/* "dirsync" */ MS_DIRSYNC,
/* "async" */ ~MS_SYNCHRONOUS,
/* "atime" */ ~MS_NOATIME,
/* "noatime" */ MS_NOATIME,
/* "diratime" */ ~MS_NODIRATIME,
/* "nodiratime" */ MS_NODIRATIME,
/* "mand" */ MS_MANDLOCK,
/* "nomand" */ ~MS_MANDLOCK,
/* "relatime" */ MS_RELATIME,
/* "norelatime" */ ~MS_RELATIME,
/* "loud" */ ~MS_SILENT,
/* "rbind" */ MS_BIND|MS_RECURSIVE,
// action flags
/* "union" */ MS_UNION,
/* "bind" */ MS_BIND,
/* "move" */ MS_MOVE,
/* "shared" */ MS_SHARED,
/* "slave" */ MS_SLAVE,
/* "private" */ MS_PRIVATE,
/* "unbindable" */ MS_UNBINDABLE,
/* "rshared" */ MS_SHARED|MS_RECURSIVE,
/* "rslave" */ MS_SLAVE|MS_RECURSIVE,
/* "rprivate" */ MS_PRIVATE|MS_RECURSIVE,
/* "runbindable" */ MS_UNBINDABLE|MS_RECURSIVE,
)
// Always understood.
/* "ro" */ MS_RDONLY, // vfs flag
/* "rw" */ ~MS_RDONLY, // vfs flag
/* "remount" */ MS_REMOUNT // action flag
};
static const char mount_option_str[] =
IF_FEATURE_MOUNT_LOOP(
"loop\0"
)
IF_FEATURE_MOUNT_FSTAB(
"defaults\0"
// "quiet\0" - do not filter out, vfat wants to see it
"noauto\0"
"sw\0"
"swap\0"
IF_DESKTOP("user\0")
IF_DESKTOP("users\0")
"_netdev\0"
)
IF_FEATURE_MOUNT_FLAGS(
// vfs flags
"nosuid\0"
"suid\0"
"dev\0"
"nodev\0"
"exec\0"
"noexec\0"
"sync\0"
"dirsync\0"
"async\0"
"atime\0"
"noatime\0"
"diratime\0"
"nodiratime\0"
"mand\0"
"nomand\0"
"relatime\0"
"norelatime\0"
"loud\0"
"rbind\0"
// action flags
"union\0"
"bind\0"
"move\0"
"make-shared\0"
"make-slave\0"
"make-private\0"
"make-unbindable\0"
"make-rshared\0"
"make-rslave\0"
"make-rprivate\0"
"make-runbindable\0"
)
// Always understood.
"ro\0" // vfs flag
"rw\0" // vfs flag
"remount\0" // action flag
;
struct globals {
#if ENABLE_FEATURE_MOUNT_NFS
smalluint nfs_mount_version;
#endif
#if ENABLE_FEATURE_MOUNT_VERBOSE
unsigned verbose;
#endif
llist_t *fslist;
char getmntent_buf[1];
} FIX_ALIASING;
enum { GETMNTENT_BUFSIZE = COMMON_BUFSIZE - offsetof(struct globals, getmntent_buf) };
#define G (*(struct globals*)&bb_common_bufsiz1)
#define nfs_mount_version (G.nfs_mount_version)
#if ENABLE_FEATURE_MOUNT_VERBOSE
#define verbose (G.verbose )
#else
#define verbose 0
#endif
#define fslist (G.fslist )
#define getmntent_buf (G.getmntent_buf )
#if ENABLE_FEATURE_MTAB_SUPPORT
/*
* update_mtab_entry_on_move() is used to update entry in case of mount --move.
* we are looking for existing entries mnt_dir which is equal to mnt_fsname of
* input mntent and replace it by new one.
*/
static void FAST_FUNC update_mtab_entry_on_move(const struct mntent *mp)
{
struct mntent *entries, *m;
int i, count;
FILE *mountTable;
mountTable = setmntent(bb_path_mtab_file, "r");
if (!mountTable) {
bb_perror_msg(bb_path_mtab_file);
return;
}
entries = NULL;
count = 0;
while ((m = getmntent(mountTable)) != NULL) {
entries = xrealloc_vector(entries, 3, count);
entries[count].mnt_fsname = xstrdup(m->mnt_fsname);
entries[count].mnt_dir = xstrdup(m->mnt_dir);
entries[count].mnt_type = xstrdup(m->mnt_type);
entries[count].mnt_opts = xstrdup(m->mnt_opts);
entries[count].mnt_freq = m->mnt_freq;
entries[count].mnt_passno = m->mnt_passno;
count++;
}
endmntent(mountTable);
mountTable = setmntent(bb_path_mtab_file, "w");
if (mountTable) {
for (i = 0; i < count; i++) {
if (strcmp(entries[i].mnt_dir, mp->mnt_fsname) != 0)
addmntent(mountTable, &entries[i]);
else
addmntent(mountTable, mp);
}
endmntent(mountTable);
} else if (errno != EROFS)
bb_perror_msg(bb_path_mtab_file);
if (ENABLE_FEATURE_CLEAN_UP) {
for (i = 0; i < count; i++) {
free(entries[i].mnt_fsname);
free(entries[i].mnt_dir);
free(entries[i].mnt_type);
free(entries[i].mnt_opts);
}
free(entries);
}
}
#endif
#if ENABLE_FEATURE_MOUNT_VERBOSE
static int verbose_mount(const char *source, const char *target,
const char *filesystemtype,
unsigned long mountflags, const void *data)
{
int rc;
errno = 0;
rc = mount(source, target, filesystemtype, mountflags, data);
if (verbose >= 2)
bb_perror_msg("mount('%s','%s','%s',0x%08lx,'%s'):%d",
source, target, filesystemtype,
mountflags, (char*)data, rc);
return rc;
}
#else
#define verbose_mount(...) mount(__VA_ARGS__)
#endif
// Append mount options to string
static void append_mount_options(char **oldopts, const char *newopts)
{
if (*oldopts && **oldopts) {
// Do not insert options which are already there
while (newopts[0]) {
char *p;
int len = strlen(newopts);
p = strchr(newopts, ',');
if (p) len = p - newopts;
p = *oldopts;
while (1) {
if (!strncmp(p, newopts, len)
&& (p[len] == ',' || p[len] == '\0'))
goto skip;
p = strchr(p,',');
if (!p) break;
p++;
}
p = xasprintf("%s,%.*s", *oldopts, len, newopts);
free(*oldopts);
*oldopts = p;
skip:
newopts += len;
while (newopts[0] == ',') newopts++;
}
} else {
if (ENABLE_FEATURE_CLEAN_UP) free(*oldopts);
*oldopts = xstrdup(newopts);
}
}
// Use the mount_options list to parse options into flags.
// Also update list of unrecognized options if unrecognized != NULL
static long parse_mount_options(char *options, char **unrecognized)
{
long flags = MS_SILENT;
// Loop through options
for (;;) {
unsigned i;
char *comma = strchr(options, ',');
const char *option_str = mount_option_str;
if (comma) *comma = '\0';
// FIXME: use hasmntopt()
// Find this option in mount_options
for (i = 0; i < ARRAY_SIZE(mount_options); i++) {
if (strcasecmp(option_str, options) == 0) {
long fl = mount_options[i];
if (fl < 0)
flags &= fl;
else
flags |= fl;
goto found;
}
option_str += strlen(option_str) + 1;
}
// We did not recognize this option.
// If "unrecognized" is not NULL, append option there.
// Note that we should not append *empty* option -
// in this case we want to pass NULL, not "", to "data"
// parameter of mount(2) syscall.
// This is crucial for filesystems that don't accept
// any arbitrary mount options, like cgroup fs:
// "mount -t cgroup none /mnt"
if (options[0] && unrecognized) {
// Add it to strflags, to pass on to kernel
char *p = *unrecognized;
unsigned len = p ? strlen(p) : 0;
*unrecognized = p = xrealloc(p, len + strlen(options) + 2);
// Comma separated if it's not the first one
if (len) p[len++] = ',';
strcpy(p + len, options);
}
found:
if (!comma)
break;
// Advance to next option
*comma = ',';
options = ++comma;
}
return flags;
}
// Return a list of all block device backed filesystems
static llist_t *get_block_backed_filesystems(void)
{
static const char filesystems[2][sizeof("/proc/filesystems")] = {
"/etc/filesystems",
"/proc/filesystems",
};
char *fs, *buf;
llist_t *list = NULL;
int i;
FILE *f;
for (i = 0; i < 2; i++) {
f = fopen_for_read(filesystems[i]);
if (!f) continue;
while ((buf = xmalloc_fgetline(f)) != NULL) {
if (strncmp(buf, "nodev", 5) == 0 && isspace(buf[5]))
continue;
fs = skip_whitespace(buf);
if (*fs == '#' || *fs == '*' || !*fs)
continue;
llist_add_to_end(&list, xstrdup(fs));
free(buf);
}
if (ENABLE_FEATURE_CLEAN_UP) fclose(f);
}
return list;
}
#if ENABLE_FEATURE_CLEAN_UP
static void delete_block_backed_filesystems(void)
{
llist_free(fslist, free);
}
#else
void delete_block_backed_filesystems(void);
#endif
// Perform actual mount of specific filesystem at specific location.
// NB: mp->xxx fields may be trashed on exit
static int mount_it_now(struct mntent *mp, long vfsflags, char *filteropts)
{
int rc = 0;
if (FAKE_IT) {
if (verbose >= 2)
bb_error_msg("would do mount('%s','%s','%s',0x%08lx,'%s')",
mp->mnt_fsname, mp->mnt_dir, mp->mnt_type,
vfsflags, filteropts);
goto mtab;
}
// Mount, with fallback to read-only if necessary.
for (;;) {
errno = 0;
rc = verbose_mount(mp->mnt_fsname, mp->mnt_dir, mp->mnt_type,
vfsflags, filteropts);
// If mount failed, try
// helper program mount.<mnt_type>
if (HELPERS_ALLOWED && rc && mp->mnt_type) {
char *args[8];
int errno_save = errno;
args[0] = xasprintf("mount.%s", mp->mnt_type);
rc = 1;
if (FAKE_IT)
args[rc++] = (char *)"-f";
if (ENABLE_FEATURE_MTAB_SUPPORT && !USE_MTAB)
args[rc++] = (char *)"-n";
args[rc++] = mp->mnt_fsname;
args[rc++] = mp->mnt_dir;
if (filteropts) {
args[rc++] = (char *)"-o";
args[rc++] = filteropts;
}
args[rc] = NULL;
rc = spawn_and_wait(args);
free(args[0]);
if (!rc)
break;
errno = errno_save;
}
if (!rc || (vfsflags & MS_RDONLY) || (errno != EACCES && errno != EROFS))
break;
if (!(vfsflags & MS_SILENT))
bb_error_msg("%s is write-protected, mounting read-only",
mp->mnt_fsname);
vfsflags |= MS_RDONLY;
}
// Abort entirely if permission denied.
if (rc && errno == EPERM)
bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
// If the mount was successful, and we're maintaining an old-style
// mtab file by hand, add the new entry to it now.
mtab:
if (USE_MTAB && !rc && !(vfsflags & MS_REMOUNT)) {
char *fsname;
FILE *mountTable = setmntent(bb_path_mtab_file, "a+");
const char *option_str = mount_option_str;
int i;
if (!mountTable) {
bb_perror_msg(bb_path_mtab_file);
goto ret;
}
// Add vfs string flags
for (i = 0; mount_options[i] != MS_REMOUNT; i++) {
if (mount_options[i] > 0 && (mount_options[i] & vfsflags))
append_mount_options(&(mp->mnt_opts), option_str);
option_str += strlen(option_str) + 1;
}
// Remove trailing / (if any) from directory we mounted on
i = strlen(mp->mnt_dir) - 1;
while (i > 0 && mp->mnt_dir[i] == '/')
mp->mnt_dir[i--] = '\0';
// Convert to canonical pathnames as needed
mp->mnt_dir = bb_simplify_path(mp->mnt_dir);
fsname = NULL;
if (!mp->mnt_type || !*mp->mnt_type) { // bind mount
mp->mnt_fsname = fsname = bb_simplify_path(mp->mnt_fsname);
mp->mnt_type = (char*)"bind";
}
mp->mnt_freq = mp->mnt_passno = 0;
// Write and close
#if ENABLE_FEATURE_MTAB_SUPPORT
if (vfsflags & MS_MOVE)
update_mtab_entry_on_move(mp);
else
#endif
addmntent(mountTable, mp);
endmntent(mountTable);
if (ENABLE_FEATURE_CLEAN_UP) {
free(mp->mnt_dir);
free(fsname);
}
}
ret:
return rc;
}
#if ENABLE_FEATURE_MOUNT_NFS
/*
* Linux NFS mount
* Copyright (C) 1993 Rick Sladkey <jrs@world.std.com>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*
* Wed Feb 8 12:51:48 1995, biro@yggdrasil.com (Ross Biro): allow all port
* numbers to be specified on the command line.
*
* Fri, 8 Mar 1996 18:01:39, Swen Thuemmler <swen@uni-paderborn.de>:
* Omit the call to connect() for Linux version 1.3.11 or later.
*
* Wed Oct 1 23:55:28 1997: Dick Streefland <dick_streefland@tasking.com>
* Implemented the "bg", "fg" and "retry" mount options for NFS.
*
* 1999-02-22 Arkadiusz Mickiewicz <misiek@misiek.eu.org>
* - added Native Language Support
*
* Modified by Olaf Kirch and Trond Myklebust for new NFS code,
* plus NFSv3 stuff.
*/
#define MOUNTPORT 635
#define MNTPATHLEN 1024
#define MNTNAMLEN 255
#define FHSIZE 32
#define FHSIZE3 64
typedef char fhandle[FHSIZE];
typedef struct {
unsigned int fhandle3_len;
char *fhandle3_val;
} fhandle3;
enum mountstat3 {
MNT_OK = 0,
MNT3ERR_PERM = 1,
MNT3ERR_NOENT = 2,
MNT3ERR_IO = 5,
MNT3ERR_ACCES = 13,
MNT3ERR_NOTDIR = 20,
MNT3ERR_INVAL = 22,
MNT3ERR_NAMETOOLONG = 63,
MNT3ERR_NOTSUPP = 10004,
MNT3ERR_SERVERFAULT = 10006,
};
typedef enum mountstat3 mountstat3;
struct fhstatus {
unsigned int fhs_status;
union {
fhandle fhs_fhandle;
} fhstatus_u;
};
typedef struct fhstatus fhstatus;
struct mountres3_ok {
fhandle3 fhandle;
struct {
unsigned int auth_flavours_len;
char *auth_flavours_val;
} auth_flavours;
};
typedef struct mountres3_ok mountres3_ok;
struct mountres3 {
mountstat3 fhs_status;
union {
mountres3_ok mountinfo;
} mountres3_u;
};
typedef struct mountres3 mountres3;
typedef char *dirpath;
typedef char *name;
typedef struct mountbody *mountlist;
struct mountbody {
name ml_hostname;
dirpath ml_directory;
mountlist ml_next;
};
typedef struct mountbody mountbody;
typedef struct groupnode *groups;
struct groupnode {
name gr_name;
groups gr_next;
};
typedef struct groupnode groupnode;
typedef struct exportnode *exports;
struct exportnode {
dirpath ex_dir;
groups ex_groups;
exports ex_next;
};
typedef struct exportnode exportnode;
struct ppathcnf {
int pc_link_max;
short pc_max_canon;
short pc_max_input;
short pc_name_max;
short pc_path_max;
short pc_pipe_buf;
uint8_t pc_vdisable;
char pc_xxx;
short pc_mask[2];
};
typedef struct ppathcnf ppathcnf;
#define MOUNTPROG 100005
#define MOUNTVERS 1
#define MOUNTPROC_NULL 0
#define MOUNTPROC_MNT 1
#define MOUNTPROC_DUMP 2
#define MOUNTPROC_UMNT 3
#define MOUNTPROC_UMNTALL 4
#define MOUNTPROC_EXPORT 5
#define MOUNTPROC_EXPORTALL 6
#define MOUNTVERS_POSIX 2
#define MOUNTPROC_PATHCONF 7
#define MOUNT_V3 3
#define MOUNTPROC3_NULL 0
#define MOUNTPROC3_MNT 1
#define MOUNTPROC3_DUMP 2
#define MOUNTPROC3_UMNT 3
#define MOUNTPROC3_UMNTALL 4
#define MOUNTPROC3_EXPORT 5
enum {
#ifndef NFS_FHSIZE
NFS_FHSIZE = 32,
#endif
#ifndef NFS_PORT
NFS_PORT = 2049
#endif
};
/*
* We want to be able to compile mount on old kernels in such a way
* that the binary will work well on more recent kernels.
* Thus, if necessary we teach nfsmount.c the structure of new fields
* that will come later.
*
* Moreover, the new kernel includes conflict with glibc includes
* so it is easiest to ignore the kernel altogether (at compile time).
*/
struct nfs2_fh {
char data[32];
};
struct nfs3_fh {
unsigned short size;
unsigned char data[64];
};
struct nfs_mount_data {
int version; /* 1 */
int fd; /* 1 */
struct nfs2_fh old_root; /* 1 */
int flags; /* 1 */
int rsize; /* 1 */
int wsize; /* 1 */
int timeo; /* 1 */
int retrans; /* 1 */
int acregmin; /* 1 */
int acregmax; /* 1 */
int acdirmin; /* 1 */
int acdirmax; /* 1 */
struct sockaddr_in addr; /* 1 */
char hostname[256]; /* 1 */
int namlen; /* 2 */
unsigned int bsize; /* 3 */
struct nfs3_fh root; /* 4 */
};
/* bits in the flags field */
enum {
NFS_MOUNT_SOFT = 0x0001, /* 1 */
NFS_MOUNT_INTR = 0x0002, /* 1 */
NFS_MOUNT_SECURE = 0x0004, /* 1 */
NFS_MOUNT_POSIX = 0x0008, /* 1 */
NFS_MOUNT_NOCTO = 0x0010, /* 1 */
NFS_MOUNT_NOAC = 0x0020, /* 1 */
NFS_MOUNT_TCP = 0x0040, /* 2 */
NFS_MOUNT_VER3 = 0x0080, /* 3 */
NFS_MOUNT_KERBEROS = 0x0100, /* 3 */
NFS_MOUNT_NONLM = 0x0200, /* 3 */
NFS_MOUNT_NORDIRPLUS = 0x4000
};
/*
* We need to translate between nfs status return values and
* the local errno values which may not be the same.
*
* Andreas Schwab <schwab@LS5.informatik.uni-dortmund.de>: change errno:
* "after #include <errno.h> the symbol errno is reserved for any use,
* it cannot even be used as a struct tag or field name".
*/
#ifndef EDQUOT
# define EDQUOT ENOSPC
#endif
/* Convert each NFSERR_BLAH into EBLAH */
static const uint8_t nfs_err_stat[] = {
1, 2, 5, 6, 13, 17,
19, 20, 21, 22, 27, 28,
30, 63, 66, 69, 70, 71
};
#if ( \
EPERM | ENOENT | EIO | ENXIO | EACCES| EEXIST | \
ENODEV| ENOTDIR | EISDIR | EINVAL| EFBIG | ENOSPC | \
EROFS | ENAMETOOLONG| ENOTEMPTY| EDQUOT| ESTALE| EREMOTE) < 256
typedef uint8_t nfs_err_type;
#else
typedef uint16_t nfs_err_type;
#endif
static const nfs_err_type nfs_err_errnum[] = {
EPERM , ENOENT , EIO , ENXIO , EACCES, EEXIST,
ENODEV, ENOTDIR , EISDIR , EINVAL, EFBIG , ENOSPC,
EROFS , ENAMETOOLONG, ENOTEMPTY, EDQUOT, ESTALE, EREMOTE
};
static char *nfs_strerror(int status)
{
int i;
for (i = 0; i < ARRAY_SIZE(nfs_err_stat); i++) {
if (nfs_err_stat[i] == status)
return strerror(nfs_err_errnum[i]);
}
return xasprintf("unknown nfs status return value: %d", status);
}
static bool_t xdr_fhandle(XDR *xdrs, fhandle objp)
{
return xdr_opaque(xdrs, objp, FHSIZE);
}
static bool_t xdr_fhstatus(XDR *xdrs, fhstatus *objp)
{
if (!xdr_u_int(xdrs, &objp->fhs_status))
return FALSE;
if (objp->fhs_status == 0)
return xdr_fhandle(xdrs, objp->fhstatus_u.fhs_fhandle);
return TRUE;
}
static bool_t xdr_dirpath(XDR *xdrs, dirpath *objp)
{
return xdr_string(xdrs, objp, MNTPATHLEN);
}
static bool_t xdr_fhandle3(XDR *xdrs, fhandle3 *objp)
{
return xdr_bytes(xdrs, (char **)&objp->fhandle3_val,
(unsigned int *) &objp->fhandle3_len,
FHSIZE3);
}
static bool_t xdr_mountres3_ok(XDR *xdrs, mountres3_ok *objp)
{
if (!xdr_fhandle3(xdrs, &objp->fhandle))
return FALSE;
return xdr_array(xdrs, &(objp->auth_flavours.auth_flavours_val),
&(objp->auth_flavours.auth_flavours_len),
~0,
sizeof(int),
(xdrproc_t) xdr_int);
}
static bool_t xdr_mountstat3(XDR *xdrs, mountstat3 *objp)
{
return xdr_enum(xdrs, (enum_t *) objp);
}
static bool_t xdr_mountres3(XDR *xdrs, mountres3 *objp)
{
if (!xdr_mountstat3(xdrs, &objp->fhs_status))
return FALSE;
if (objp->fhs_status == MNT_OK)
return xdr_mountres3_ok(xdrs, &objp->mountres3_u.mountinfo);
return TRUE;
}
#define MAX_NFSPROT ((nfs_mount_version >= 4) ? 3 : 2)
/*
* Unfortunately, the kernel prints annoying console messages
* in case of an unexpected nfs mount version (instead of
* just returning some error). Therefore we'll have to try
* and figure out what version the kernel expects.
*
* Variables:
* KERNEL_NFS_MOUNT_VERSION: kernel sources at compile time
* NFS_MOUNT_VERSION: these nfsmount sources at compile time
* nfs_mount_version: version this source and running kernel can handle
*/
static void
find_kernel_nfs_mount_version(void)
{
int kernel_version;
if (nfs_mount_version)
return;
nfs_mount_version = 4; /* default */
kernel_version = get_linux_version_code();
if (kernel_version) {
if (kernel_version < KERNEL_VERSION(2,2,18))
nfs_mount_version = 3;
/* else v4 since 2.3.99pre4 */
}
}
static void
get_mountport(struct pmap *pm_mnt,
struct sockaddr_in *server_addr,
long unsigned prog,
long unsigned version,
long unsigned proto,
long unsigned port)
{
struct pmaplist *pmap;
server_addr->sin_port = PMAPPORT;
/* glibc 2.4 (still) has pmap_getmaps(struct sockaddr_in *).
* I understand it like "IPv6 for this is not 100% ready" */
pmap = pmap_getmaps(server_addr);
if (version > MAX_NFSPROT)
version = MAX_NFSPROT;
if (!prog)
prog = MOUNTPROG;
pm_mnt->pm_prog = prog;
pm_mnt->pm_vers = version;
pm_mnt->pm_prot = proto;
pm_mnt->pm_port = port;
while (pmap) {
if (pmap->pml_map.pm_prog != prog)
goto next;
if (!version && pm_mnt->pm_vers > pmap->pml_map.pm_vers)
goto next;
if (version > 2 && pmap->pml_map.pm_vers != version)
goto next;
if (version && version <= 2 && pmap->pml_map.pm_vers > 2)
goto next;
if (pmap->pml_map.pm_vers > MAX_NFSPROT
|| (proto && pm_mnt->pm_prot && pmap->pml_map.pm_prot != proto)
|| (port && pmap->pml_map.pm_port != port)
) {
goto next;
}
memcpy(pm_mnt, &pmap->pml_map, sizeof(*pm_mnt));
next:
pmap = pmap->pml_next;
}
if (!pm_mnt->pm_vers)
pm_mnt->pm_vers = MOUNTVERS;
if (!pm_mnt->pm_port)
pm_mnt->pm_port = MOUNTPORT;
if (!pm_mnt->pm_prot)
pm_mnt->pm_prot = IPPROTO_TCP;
}
#if BB_MMU
static int daemonize(void)
{
int pid = fork();
if (pid < 0) /* error */
return -errno;
if (pid > 0) /* parent */
return 0;
/* child */
close(0);
xopen(bb_dev_null, O_RDWR);
xdup2(0, 1);
xdup2(0, 2);
setsid();
openlog(applet_name, LOG_PID, LOG_DAEMON);
logmode = LOGMODE_SYSLOG;
return 1;
}
#else
static inline int daemonize(void) { return -ENOSYS; }
#endif
/* TODO */
static inline int we_saw_this_host_before(const char *hostname UNUSED_PARAM)
{
return 0;
}
/* RPC strerror analogs are terminally idiotic:
* *mandatory* prefix and \n at end.
* This hopefully helps. Usage:
* error_msg_rpc(clnt_*error*(" ")) */
static void error_msg_rpc(const char *msg)
{
int len;
while (msg[0] == ' ' || msg[0] == ':') msg++;
len = strlen(msg);
while (len && msg[len-1] == '\n') len--;
bb_error_msg("%.*s", len, msg);
}
/* NB: mp->xxx fields may be trashed on exit */
static NOINLINE int nfsmount(struct mntent *mp, long vfsflags, char *filteropts)
{
CLIENT *mclient;
char *hostname;
char *pathname;
char *mounthost;
/* prior to 2.6.23, kernel took NFS options in a form of this struct
* only. 2.6.23+ looks at data->version, and if it's not 1..6,
* then data pointer is interpreted as a string. */
struct nfs_mount_data data;
char *opt;
struct hostent *hp;
struct sockaddr_in server_addr;
struct sockaddr_in mount_server_addr;
int msock, fsock;
union {
struct fhstatus nfsv2;
struct mountres3 nfsv3;
} status;
int daemonized;
char *s;
int port;
int mountport;
int proto;
#if BB_MMU
smallint bg = 0;
#else
enum { bg = 0 };
#endif
int retry;
int mountprog;
int mountvers;
int nfsprog;
int nfsvers;
int retval;
/* these all are one-bit really. gcc 4.3.1 likes this combination: */
smallint tcp;
smallint soft;
int intr;
int posix;
int nocto;
int noac;
int nordirplus;
int nolock;
find_kernel_nfs_mount_version();
daemonized = 0;
mounthost = NULL;
retval = ETIMEDOUT;
msock = fsock = -1;
mclient = NULL;
/* NB: hostname, mounthost, filteropts must be free()d prior to return */
filteropts = xstrdup(filteropts); /* going to trash it later... */
hostname = xstrdup(mp->mnt_fsname);
/* mount_main() guarantees that ':' is there */
s = strchr(hostname, ':');
pathname = s + 1;
*s = '\0';
/* Ignore all but first hostname in replicated mounts
until they can be fully supported. (mack@sgi.com) */
s = strchr(hostname, ',');
if (s) {
*s = '\0';
bb_error_msg("warning: multiple hostnames not supported");
}
server_addr.sin_family = AF_INET;
if (!inet_aton(hostname, &server_addr.sin_addr)) {
hp = gethostbyname(hostname);
if (hp == NULL) {
bb_herror_msg("%s", hostname);
goto fail;
}
if (hp->h_length != (int)sizeof(struct in_addr)) {
bb_error_msg_and_die("only IPv4 is supported");
}
memcpy(&server_addr.sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
}
memcpy(&mount_server_addr, &server_addr, sizeof(mount_server_addr));
/* add IP address to mtab options for use when unmounting */
if (!mp->mnt_opts) { /* TODO: actually mp->mnt_opts is never NULL */
mp->mnt_opts = xasprintf("addr=%s", inet_ntoa(server_addr.sin_addr));
} else {
char *tmp = xasprintf("%s%saddr=%s", mp->mnt_opts,
mp->mnt_opts[0] ? "," : "",
inet_ntoa(server_addr.sin_addr));
free(mp->mnt_opts);
mp->mnt_opts = tmp;
}
/* Set default options.
* rsize/wsize (and bsize, for ver >= 3) are left 0 in order to
* let the kernel decide.
* timeo is filled in after we know whether it'll be TCP or UDP. */
memset(&data, 0, sizeof(data));
data.retrans = 3;
data.acregmin = 3;
data.acregmax = 60;
data.acdirmin = 30;
data.acdirmax = 60;
data.namlen = NAME_MAX;
soft = 0;
intr = 0;
posix = 0;
nocto = 0;
nolock = 0;
noac = 0;
nordirplus = 0;
retry = 10000; /* 10000 minutes ~ 1 week */
tcp = 0;
mountprog = MOUNTPROG;
mountvers = 0;
port = 0;
mountport = 0;
nfsprog = 100003;
nfsvers = 0;
/* parse options */
if (filteropts) for (opt = strtok(filteropts, ","); opt; opt = strtok(NULL, ",")) {
char *opteq = strchr(opt, '=');
if (opteq) {
int val, idx;
static const char options[] ALIGN1 =
/* 0 */ "rsize\0"
/* 1 */ "wsize\0"
/* 2 */ "timeo\0"
/* 3 */ "retrans\0"
/* 4 */ "acregmin\0"
/* 5 */ "acregmax\0"
/* 6 */ "acdirmin\0"
/* 7 */ "acdirmax\0"
/* 8 */ "actimeo\0"
/* 9 */ "retry\0"
/* 10 */ "port\0"
/* 11 */ "mountport\0"
/* 12 */ "mounthost\0"
/* 13 */ "mountprog\0"
/* 14 */ "mountvers\0"
/* 15 */ "nfsprog\0"
/* 16 */ "nfsvers\0"
/* 17 */ "vers\0"
/* 18 */ "proto\0"
/* 19 */ "namlen\0"
/* 20 */ "addr\0";
*opteq++ = '\0';
idx = index_in_strings(options, opt);
switch (idx) {
case 12: // "mounthost"
mounthost = xstrndup(opteq,
strcspn(opteq, " \t\n\r,"));
continue;
case 18: // "proto"
if (!strncmp(opteq, "tcp", 3))
tcp = 1;
else if (!strncmp(opteq, "udp", 3))
tcp = 0;
else
bb_error_msg("warning: unrecognized proto= option");
continue;
case 20: // "addr" - ignore
continue;
case -1: // unknown
if (vfsflags & MS_REMOUNT)
continue;
}
val = xatoi_positive(opteq);
switch (idx) {
case 0: // "rsize"
data.rsize = val;
continue;
case 1: // "wsize"
data.wsize = val;
continue;
case 2: // "timeo"
data.timeo = val;
continue;
case 3: // "retrans"
data.retrans = val;
continue;
case 4: // "acregmin"
data.acregmin = val;
continue;
case 5: // "acregmax"
data.acregmax = val;
continue;
case 6: // "acdirmin"
data.acdirmin = val;
continue;
case 7: // "acdirmax"
data.acdirmax = val;
continue;
case 8: // "actimeo"
data.acregmin = val;
data.acregmax = val;
data.acdirmin = val;
data.acdirmax = val;
continue;
case 9: // "retry"
retry = val;
continue;
case 10: // "port"
port = val;
continue;
case 11: // "mountport"
mountport = val;
continue;
case 13: // "mountprog"
mountprog = val;
continue;
case 14: // "mountvers"
mountvers = val;
continue;
case 15: // "nfsprog"
nfsprog = val;
continue;
case 16: // "nfsvers"
case 17: // "vers"
nfsvers = val;
continue;
case 19: // "namlen"
//if (nfs_mount_version >= 2)
data.namlen = val;
//else
// bb_error_msg("warning: option namlen is not supported\n");
continue;
default:
bb_error_msg("unknown nfs mount parameter: %s=%d", opt, val);
goto fail;
}
}
else { /* not of the form opt=val */
static const char options[] ALIGN1 =
"bg\0"
"fg\0"
"soft\0"
"hard\0"
"intr\0"
"posix\0"
"cto\0"
"ac\0"
"tcp\0"
"udp\0"
"lock\0"
"rdirplus\0";
int val = 1;
if (!strncmp(opt, "no", 2)) {
val = 0;
opt += 2;
}
switch (index_in_strings(options, opt)) {
case 0: // "bg"
#if BB_MMU
bg = val;
#endif
break;
case 1: // "fg"
#if BB_MMU
bg = !val;
#endif
break;
case 2: // "soft"
soft = val;
break;
case 3: // "hard"
soft = !val;
break;
case 4: // "intr"
intr = val;
break;
case 5: // "posix"
posix = val;
break;
case 6: // "cto"
nocto = !val;
break;
case 7: // "ac"
noac = !val;
break;
case 8: // "tcp"
tcp = val;
break;
case 9: // "udp"
tcp = !val;
break;
case 10: // "lock"
if (nfs_mount_version >= 3)
nolock = !val;
else
bb_error_msg("warning: option nolock is not supported");
break;
case 11: //rdirplus
nordirplus = !val;
break;
default:
bb_error_msg("unknown nfs mount option: %s%s", val ? "" : "no", opt);
goto fail;
}
}
}
proto = (tcp) ? IPPROTO_TCP : IPPROTO_UDP;
data.flags = (soft ? NFS_MOUNT_SOFT : 0)
| (intr ? NFS_MOUNT_INTR : 0)
| (posix ? NFS_MOUNT_POSIX : 0)
| (nocto ? NFS_MOUNT_NOCTO : 0)
| (noac ? NFS_MOUNT_NOAC : 0)
| (nordirplus ? NFS_MOUNT_NORDIRPLUS : 0);
if (nfs_mount_version >= 2)
data.flags |= (tcp ? NFS_MOUNT_TCP : 0);
if (nfs_mount_version >= 3)
data.flags |= (nolock ? NFS_MOUNT_NONLM : 0);
if (nfsvers > MAX_NFSPROT || mountvers > MAX_NFSPROT) {
bb_error_msg("NFSv%d not supported", nfsvers);
goto fail;
}
if (nfsvers && !mountvers)
mountvers = (nfsvers < 3) ? 1 : nfsvers;
if (nfsvers && nfsvers < mountvers) {
mountvers = nfsvers;
}
/* Adjust options if none specified */
if (!data.timeo)
data.timeo = tcp ? 70 : 7;
data.version = nfs_mount_version;
if (vfsflags & MS_REMOUNT)
goto do_mount;
/*
* If the previous mount operation on the same host was
* backgrounded, and the "bg" for this mount is also set,
* give up immediately, to avoid the initial timeout.
*/
if (bg && we_saw_this_host_before(hostname)) {
daemonized = daemonize();
if (daemonized <= 0) { /* parent or error */
retval = -daemonized;
goto ret;
}
}
/* Create mount daemon client */
/* See if the nfs host = mount host. */
if (mounthost) {
if (mounthost[0] >= '0' && mounthost[0] <= '9') {
mount_server_addr.sin_family = AF_INET;
mount_server_addr.sin_addr.s_addr = inet_addr(hostname);
} else {
hp = gethostbyname(mounthost);
if (hp == NULL) {
bb_herror_msg("%s", mounthost);
goto fail;
}
if (hp->h_length != (int)sizeof(struct in_addr)) {
bb_error_msg_and_die("only IPv4 is supported");
}
mount_server_addr.sin_family = AF_INET;
memcpy(&mount_server_addr.sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
}
}
/*
* The following loop implements the mount retries. When the mount
* times out, and the "bg" option is set, we background ourself
* and continue trying.
*
* The case where the mount point is not present and the "bg"
* option is set, is treated as a timeout. This is done to
* support nested mounts.
*
* The "retry" count specified by the user is the number of
* minutes to retry before giving up.
*/
{
struct timeval total_timeout;
struct timeval retry_timeout;
struct pmap pm_mnt;
time_t t;
time_t prevt;
time_t timeout;
retry_timeout.tv_sec = 3;
retry_timeout.tv_usec = 0;
total_timeout.tv_sec = 20;
total_timeout.tv_usec = 0;
/* FIXME: use monotonic()? */
timeout = time(NULL) + 60 * retry;
prevt = 0;
t = 30;
retry:
/* Be careful not to use too many CPU cycles */
if (t - prevt < 30)
sleep(30);
get_mountport(&pm_mnt, &mount_server_addr,
mountprog,
mountvers,
proto,
mountport);
nfsvers = (pm_mnt.pm_vers < 2) ? 2 : pm_mnt.pm_vers;
/* contact the mount daemon via TCP */
mount_server_addr.sin_port = htons(pm_mnt.pm_port);
msock = RPC_ANYSOCK;
switch (pm_mnt.pm_prot) {
case IPPROTO_UDP:
mclient = clntudp_create(&mount_server_addr,
pm_mnt.pm_prog,
pm_mnt.pm_vers,
retry_timeout,
&msock);
if (mclient)
break;
mount_server_addr.sin_port = htons(pm_mnt.pm_port);
msock = RPC_ANYSOCK;
case IPPROTO_TCP:
mclient = clnttcp_create(&mount_server_addr,
pm_mnt.pm_prog,
pm_mnt.pm_vers,
&msock, 0, 0);
break;
default:
mclient = NULL;
}
if (!mclient) {
if (!daemonized && prevt == 0)
error_msg_rpc(clnt_spcreateerror(" "));
} else {
enum clnt_stat clnt_stat;
/* Try to mount hostname:pathname */
mclient->cl_auth = authunix_create_default();
/* Make pointers in xdr_mountres3 NULL so
* that xdr_array allocates memory for us
*/
memset(&status, 0, sizeof(status));
if (pm_mnt.pm_vers == 3)
clnt_stat = clnt_call(mclient, MOUNTPROC3_MNT,
(xdrproc_t) xdr_dirpath,
(caddr_t) &pathname,
(xdrproc_t) xdr_mountres3,
(caddr_t) &status,
total_timeout);
else
clnt_stat = clnt_call(mclient, MOUNTPROC_MNT,
(xdrproc_t) xdr_dirpath,
(caddr_t) &pathname,
(xdrproc_t) xdr_fhstatus,
(caddr_t) &status,
total_timeout);
if (clnt_stat == RPC_SUCCESS)
goto prepare_kernel_data; /* we're done */
if (errno != ECONNREFUSED) {
error_msg_rpc(clnt_sperror(mclient, " "));
goto fail; /* don't retry */
}
/* Connection refused */
if (!daemonized && prevt == 0) /* print just once */
error_msg_rpc(clnt_sperror(mclient, " "));
auth_destroy(mclient->cl_auth);
clnt_destroy(mclient);
mclient = NULL;
close(msock);
msock = -1;
}
/* Timeout. We are going to retry... maybe */
if (!bg)
goto fail;
if (!daemonized) {
daemonized = daemonize();
if (daemonized <= 0) { /* parent or error */
retval = -daemonized;
goto ret;
}
}
prevt = t;
t = time(NULL);
if (t >= timeout)
/* TODO error message */
goto fail;
goto retry;
}
prepare_kernel_data:
if (nfsvers == 2) {
if (status.nfsv2.fhs_status != 0) {
bb_error_msg("%s:%s failed, reason given by server: %s",
hostname, pathname,
nfs_strerror(status.nfsv2.fhs_status));
goto fail;
}
memcpy(data.root.data,
(char *) status.nfsv2.fhstatus_u.fhs_fhandle,
NFS_FHSIZE);
data.root.size = NFS_FHSIZE;
memcpy(data.old_root.data,
(char *) status.nfsv2.fhstatus_u.fhs_fhandle,
NFS_FHSIZE);
} else {
fhandle3 *my_fhandle;
if (status.nfsv3.fhs_status != 0) {
bb_error_msg("%s:%s failed, reason given by server: %s",
hostname, pathname,
nfs_strerror(status.nfsv3.fhs_status));
goto fail;
}
my_fhandle = &status.nfsv3.mountres3_u.mountinfo.fhandle;
memset(data.old_root.data, 0, NFS_FHSIZE);
memset(&data.root, 0, sizeof(data.root));
data.root.size = my_fhandle->fhandle3_len;
memcpy(data.root.data,
(char *) my_fhandle->fhandle3_val,
my_fhandle->fhandle3_len);
data.flags |= NFS_MOUNT_VER3;
}
/* Create nfs socket for kernel */
if (tcp) {
if (nfs_mount_version < 3) {
bb_error_msg("NFS over TCP is not supported");
goto fail;
}
fsock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
} else
fsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (fsock < 0) {
bb_perror_msg("nfs socket");
goto fail;
}
if (bindresvport(fsock, 0) < 0) {
bb_perror_msg("nfs bindresvport");
goto fail;
}
if (port == 0) {
server_addr.sin_port = PMAPPORT;
port = pmap_getport(&server_addr, nfsprog, nfsvers,
tcp ? IPPROTO_TCP : IPPROTO_UDP);
if (port == 0)
port = NFS_PORT;
}
server_addr.sin_port = htons(port);
/* Prepare data structure for kernel */
data.fd = fsock;
memcpy((char *) &data.addr, (char *) &server_addr, sizeof(data.addr));
strncpy(data.hostname, hostname, sizeof(data.hostname));
/* Clean up */
auth_destroy(mclient->cl_auth);
clnt_destroy(mclient);
close(msock);
msock = -1;
if (bg) {
/* We must wait until mount directory is available */
struct stat statbuf;
int delay = 1;
while (stat(mp->mnt_dir, &statbuf) == -1) {
if (!daemonized) {
daemonized = daemonize();
if (daemonized <= 0) { /* parent or error */
/* FIXME: parent doesn't close fsock - ??! */
retval = -daemonized;
goto ret;
}
}
sleep(delay); /* 1, 2, 4, 8, 16, 30, ... */
delay *= 2;
if (delay > 30)
delay = 30;
}
}
/* Perform actual mount */
do_mount:
mp->mnt_type = (char*)"nfs";
retval = mount_it_now(mp, vfsflags, (char*)&data);
goto ret;
/* Abort */
fail:
if (msock >= 0) {
if (mclient) {
auth_destroy(mclient->cl_auth);
clnt_destroy(mclient);
}
close(msock);
}
if (fsock >= 0)
close(fsock);
ret:
free(hostname);
free(mounthost);
free(filteropts);
return retval;
}
#else // !ENABLE_FEATURE_MOUNT_NFS
// Never called. Call should be optimized out.
int nfsmount(struct mntent *mp, long vfsflags, char *filteropts);
#endif // !ENABLE_FEATURE_MOUNT_NFS
// Mount one directory. Handles CIFS, NFS, loopback, autobind, and filesystem
// type detection. Returns 0 for success, nonzero for failure.
// NB: mp->xxx fields may be trashed on exit
static int singlemount(struct mntent *mp, int ignore_busy)
{
int rc = -1;
long vfsflags;
char *loopFile = NULL, *filteropts = NULL;
llist_t *fl = NULL;
struct stat st;
errno = 0;
vfsflags = parse_mount_options(mp->mnt_opts, &filteropts);
// Treat fstype "auto" as unspecified
if (mp->mnt_type && strcmp(mp->mnt_type, "auto") == 0)
mp->mnt_type = NULL;
// Might this be a virtual filesystem?
if (ENABLE_FEATURE_MOUNT_HELPERS && strchr(mp->mnt_fsname, '#')) {
char *args[35];
char *s;
int n;
// fsname: "cmd#arg1#arg2..."
// WARNING: allows execution of arbitrary commands!
// Try "mount 'sh#-c#sh' bogus_dir".
// It is safe ONLY because non-root
// cannot use two-argument mount command
// and using one-argument "mount 'sh#-c#sh'" doesn't work:
// "mount: can't find sh#-c#sh in /etc/fstab"
// (if /etc/fstab has it, it's ok: root sets up /etc/fstab).
s = mp->mnt_fsname;
n = 0;
args[n++] = s;
while (*s && n < 35 - 2) {
if (*s++ == '#' && *s != '#') {
s[-1] = '\0';
args[n++] = s;
}
}
args[n++] = mp->mnt_dir;
args[n] = NULL;
rc = spawn_and_wait(args);
goto report_error;
}
// Might this be an CIFS filesystem?
if (ENABLE_FEATURE_MOUNT_CIFS
&& (!mp->mnt_type || strcmp(mp->mnt_type, "cifs") == 0)
&& (mp->mnt_fsname[0] == '/' || mp->mnt_fsname[0] == '\\')
&& mp->mnt_fsname[0] == mp->mnt_fsname[1]
) {
int len;
char c;
len_and_sockaddr *lsa;
char *hostname, *dotted, *ip;
hostname = mp->mnt_fsname + 2;
len = strcspn(hostname, "/\\");
if (len == 0 || hostname[len] == '\0')
goto report_error;
c = hostname[len];
hostname[len] = '\0';
lsa = host2sockaddr(hostname, 0);
hostname[len] = c;
if (!lsa)
goto report_error;
// Insert "ip=..." option into options
dotted = xmalloc_sockaddr2dotted_noport(&lsa->u.sa);
if (ENABLE_FEATURE_CLEAN_UP) free(lsa);
ip = xasprintf("ip=%s", dotted);
if (ENABLE_FEATURE_CLEAN_UP) free(dotted);
parse_mount_options(ip, &filteropts);
if (ENABLE_FEATURE_CLEAN_UP) free(ip);
// "-o mand" is required [why?]
vfsflags |= MS_MANDLOCK;
mp->mnt_type = (char*)"cifs";
rc = mount_it_now(mp, vfsflags, filteropts);
goto report_error;
}
// Might this be an NFS filesystem?
if (ENABLE_FEATURE_MOUNT_NFS
&& (!mp->mnt_type || strcmp(mp->mnt_type, "nfs") == 0)
&& strchr(mp->mnt_fsname, ':') != NULL
) {
rc = nfsmount(mp, vfsflags, filteropts);
goto report_error;
}
// Look at the file. (Not found isn't a failure for remount, or for
// a synthetic filesystem like proc or sysfs.)
// (We use stat, not lstat, in order to allow
// mount symlink_to_file_or_blkdev dir)
if (!stat(mp->mnt_fsname, &st)
&& !(vfsflags & (MS_REMOUNT | MS_BIND | MS_MOVE))
) {
// Do we need to allocate a loopback device for it?
if (ENABLE_FEATURE_MOUNT_LOOP && S_ISREG(st.st_mode)) {
loopFile = bb_simplify_path(mp->mnt_fsname);
mp->mnt_fsname = NULL; // will receive malloced loop dev name
if (set_loop(&mp->mnt_fsname, loopFile, 0) < 0) {
if (errno == EPERM || errno == EACCES)
bb_error_msg(bb_msg_perm_denied_are_you_root);
else
bb_perror_msg("can't setup loop device");
return errno;
}
// Autodetect bind mounts
} else if (S_ISDIR(st.st_mode) && !mp->mnt_type)
vfsflags |= MS_BIND;
}
// If we know the fstype (or don't need to), jump straight
// to the actual mount.
if (mp->mnt_type || (vfsflags & (MS_REMOUNT | MS_BIND | MS_MOVE))) {
rc = mount_it_now(mp, vfsflags, filteropts);
} else {
// Loop through filesystem types until mount succeeds
// or we run out
// Initialize list of block backed filesystems.
// This has to be done here so that during "mount -a",
// mounts after /proc shows up can autodetect.
if (!fslist) {
fslist = get_block_backed_filesystems();
if (ENABLE_FEATURE_CLEAN_UP && fslist)
atexit(delete_block_backed_filesystems);
}
for (fl = fslist; fl; fl = fl->link) {
mp->mnt_type = fl->data;
rc = mount_it_now(mp, vfsflags, filteropts);
if (!rc)
break;
}
}
// If mount failed, clean up loop file (if any).
if (ENABLE_FEATURE_MOUNT_LOOP && rc && loopFile) {
del_loop(mp->mnt_fsname);
if (ENABLE_FEATURE_CLEAN_UP) {
free(loopFile);
free(mp->mnt_fsname);
}
}
report_error:
if (ENABLE_FEATURE_CLEAN_UP)
free(filteropts);
if (errno == EBUSY && ignore_busy)
return 0;
if (rc != 0)
bb_perror_msg("mounting %s on %s failed", mp->mnt_fsname, mp->mnt_dir);
return rc;
}
// -O support
// -O interprets a list of filter options which select whether a mount
// point will be mounted: only mounts with options matching *all* filtering
// options will be selected.
// By default each -O filter option must be present in the list of mount
// options, but if it is prefixed by "no" then it must be absent.
// For example,
// -O a,nob,c matches -o a,c but fails to match -o a,b,c
// (and also fails to match -o a because -o c is absent).
//
// It is different from -t in that each option is matched exactly; a leading
// "no" at the beginning of one option does not negate the rest.
static int match_opt(const char *fs_opt_in, const char *O_opt)
{
if (!O_opt)
return 1;
while (*O_opt) {
const char *fs_opt = fs_opt_in;
int O_len;
int match;
// If option begins with "no" then treat as an inverted match:
// matching is a failure
match = 0;
if (O_opt[0] == 'n' && O_opt[1] == 'o') {
match = 1;
O_opt += 2;
}
// Isolate the current O option
O_len = strchrnul(O_opt, ',') - O_opt;
// Check for a match against existing options
while (1) {
if (strncmp(fs_opt, O_opt, O_len) == 0
&& (fs_opt[O_len] == '\0' || fs_opt[O_len] == ',')
) {
if (match)
return 0; // "no" prefix, but option found
match = 1; // current O option found, go check next one
break;
}
fs_opt = strchr(fs_opt, ',');
if (!fs_opt)
break;
fs_opt++;
}
if (match == 0)
return 0; // match wanted but not found
if (O_opt[O_len] == '\0') // end?
break;
// Step to the next O option
O_opt += O_len + 1;
}
// If we get here then everything matched
return 1;
}
// Parse options, if necessary parse fstab/mtab, and call singlemount for
// each directory to be mounted.
int mount_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mount_main(int argc UNUSED_PARAM, char **argv)
{
char *cmdopts = xzalloc(1);
char *fstype = NULL;
char *O_optmatch = NULL;
char *storage_path;
llist_t *lst_o = NULL;
const char *fstabname;
FILE *fstab;
int i, j;
int rc = EXIT_SUCCESS;
unsigned opt;
struct mntent mtpair[2], *mtcur = mtpair;
IF_NOT_DESKTOP(const int nonroot = 0;)
IF_DESKTOP(int nonroot = ) sanitize_env_if_suid();
// Parse long options, like --bind and --move. Note that -o option
// and --option are synonymous. Yes, this means --remount,rw works.
for (i = j = 1; argv[i]; i++) {
if (argv[i][0] == '-' && argv[i][1] == '-')
append_mount_options(&cmdopts, argv[i] + 2);
else
argv[j++] = argv[i];
}
argv[j] = NULL;
// Parse remaining options
// Max 2 params; -o is a list, -v is a counter
opt_complementary = "?2o::" IF_FEATURE_MOUNT_VERBOSE("vv");
opt = getopt32(argv, OPTION_STR, &lst_o, &fstype, &O_optmatch
IF_FEATURE_MOUNT_VERBOSE(, &verbose));
while (lst_o) append_mount_options(&cmdopts, llist_pop(&lst_o)); // -o
if (opt & OPT_r) append_mount_options(&cmdopts, "ro"); // -r
if (opt & OPT_w) append_mount_options(&cmdopts, "rw"); // -w
argv += optind;
// If we have no arguments, show currently mounted filesystems
if (!argv[0]) {
if (!(opt & OPT_a)) {
FILE *mountTable = setmntent(bb_path_mtab_file, "r");
if (!mountTable)
bb_error_msg_and_die("no %s", bb_path_mtab_file);
while (getmntent_r(mountTable, &mtpair[0], getmntent_buf,
GETMNTENT_BUFSIZE))
{
// Don't show rootfs. FIXME: why??
// util-linux 2.12a happily shows rootfs...
//if (strcmp(mtpair->mnt_fsname, "rootfs") == 0) continue;
if (!fstype || strcmp(mtpair->mnt_type, fstype) == 0)
printf("%s on %s type %s (%s)\n", mtpair->mnt_fsname,
mtpair->mnt_dir, mtpair->mnt_type,
mtpair->mnt_opts);
}
if (ENABLE_FEATURE_CLEAN_UP)
endmntent(mountTable);
return EXIT_SUCCESS;
}
storage_path = NULL;
} else {
// When we have two arguments, the second is the directory and we can
// skip looking at fstab entirely. We can always abspath() the directory
// argument when we get it.
if (argv[1]) {
if (nonroot)
bb_error_msg_and_die(bb_msg_you_must_be_root);
mtpair->mnt_fsname = argv[0];
mtpair->mnt_dir = argv[1];
mtpair->mnt_type = fstype;
mtpair->mnt_opts = cmdopts;
resolve_mount_spec(&mtpair->mnt_fsname);
rc = singlemount(mtpair, /*ignore_busy:*/ 0);
return rc;
}
storage_path = bb_simplify_path(argv[0]); // malloced
}
// Past this point, we are handling either "mount -a [opts]"
// or "mount [opts] single_param"
i = parse_mount_options(cmdopts, NULL); // FIXME: should be "long", not "int"
if (nonroot && (i & ~MS_SILENT)) // Non-root users cannot specify flags
bb_error_msg_and_die(bb_msg_you_must_be_root);
// If we have a shared subtree flag, don't worry about fstab or mtab.
if (ENABLE_FEATURE_MOUNT_FLAGS
&& (i & (MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE))
) {
// verbose_mount(source, target, type, flags, data)
rc = verbose_mount("", argv[0], "", i, "");
if (rc)
bb_simple_perror_msg_and_die(argv[0]);
return rc;
}
// Open either fstab or mtab
fstabname = "/etc/fstab";
if (i & MS_REMOUNT) {
// WARNING. I am not sure this matches util-linux's
// behavior. It's possible util-linux does not
// take -o opts from mtab (takes only mount source).
fstabname = bb_path_mtab_file;
}
fstab = setmntent(fstabname, "r");
if (!fstab)
bb_perror_msg_and_die("can't read '%s'", fstabname);
// Loop through entries until we find what we're looking for
memset(mtpair, 0, sizeof(mtpair));
for (;;) {
struct mntent *mtother = (mtcur==mtpair ? mtpair+1 : mtpair);
// Get next fstab entry
if (!getmntent_r(fstab, mtcur, getmntent_buf
+ (mtcur==mtpair ? GETMNTENT_BUFSIZE/2 : 0),
GETMNTENT_BUFSIZE/2)
) { // End of fstab/mtab is reached
mtcur = mtother; // the thing we found last time
break;
}
// If we're trying to mount something specific and this isn't it,
// skip it. Note we must match the exact text in fstab (ala
// "proc") or a full path from root
if (argv[0]) {
// Is this what we're looking for?
if (strcmp(argv[0], mtcur->mnt_fsname) != 0
&& strcmp(storage_path, mtcur->mnt_fsname) != 0
&& strcmp(argv[0], mtcur->mnt_dir) != 0
&& strcmp(storage_path, mtcur->mnt_dir) != 0
) {
continue; // no
}
// Remember this entry. Something later may have
// overmounted it, and we want the _last_ match.
mtcur = mtother;
// If we're mounting all
} else {
struct mntent *mp;
// No, mount -a won't mount anything,
// even user mounts, for mere humans
if (nonroot)
bb_error_msg_and_die(bb_msg_you_must_be_root);
// Does type match? (NULL matches always)
if (!match_fstype(mtcur, fstype))
continue;
// Skip noauto and swap anyway
if ((parse_mount_options(mtcur->mnt_opts, NULL) & (MOUNT_NOAUTO | MOUNT_SWAP))
// swap is bogus "fstype", parse_mount_options can't check fstypes
|| strcasecmp(mtcur->mnt_type, "swap") == 0
) {
continue;
}
// Does (at least one) option match?
// (NULL matches always)
if (!match_opt(mtcur->mnt_opts, O_optmatch))
continue;
resolve_mount_spec(&mtcur->mnt_fsname);
// NFS mounts want this to be xrealloc-able
mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
// If nothing is mounted on this directory...
// (otherwise repeated "mount -a" mounts everything again)
mp = find_mount_point(mtcur->mnt_dir, /*subdir_too:*/ 0);
// We do not check fsname match of found mount point -
// "/" may have fsname of "/dev/root" while fstab
// says "/dev/something_else".
if (mp) {
if (verbose) {
bb_error_msg("according to %s, "
"%s is already mounted on %s",
bb_path_mtab_file,
mp->mnt_fsname, mp->mnt_dir);
}
} else {
// ...mount this thing
if (singlemount(mtcur, /*ignore_busy:*/ 1)) {
// Count number of failed mounts
rc++;
}
}
free(mtcur->mnt_opts);
}
}
// End of fstab/mtab is reached.
// Were we looking for something specific?
if (argv[0]) { // yes
long l;
// If we didn't find anything, complain
if (!mtcur->mnt_fsname)
bb_error_msg_and_die("can't find %s in %s",
argv[0], fstabname);
// What happens when we try to "mount swap_partition"?
// (fstab containts "swap_partition swap swap defaults 0 0")
// util-linux-ng 2.13.1 does this:
// stat("/sbin/mount.swap", 0x7fff62a3a350) = -1 ENOENT (No such file or directory)
// mount("swap_partition", "swap", "swap", MS_MGC_VAL, NULL) = -1 ENOENT (No such file or directory)
// lstat("swap", 0x7fff62a3a640) = -1 ENOENT (No such file or directory)
// write(2, "mount: mount point swap does not exist\n", 39) = 39
// exit_group(32) = ?
#if 0
// In case we want to simply skip swap partitions:
l = parse_mount_options(mtcur->mnt_opts, NULL);
if ((l & MOUNT_SWAP)
// swap is bogus "fstype", parse_mount_options can't check fstypes
|| strcasecmp(mtcur->mnt_type, "swap") == 0
) {
goto ret;
}
#endif
if (nonroot) {
// fstab must have "users" or "user"
l = parse_mount_options(mtcur->mnt_opts, NULL);
if (!(l & MOUNT_USERS))
bb_error_msg_and_die(bb_msg_you_must_be_root);
}
//util-linux-2.12 does not do this check.
//// If nothing is mounted on this directory...
//// (otherwise repeated "mount FOO" mounts FOO again)
//mp = find_mount_point(mtcur->mnt_dir, /*subdir_too:*/ 0);
//if (mp) {
// bb_error_msg("according to %s, "
// "%s is already mounted on %s",
// bb_path_mtab_file,
// mp->mnt_fsname, mp->mnt_dir);
//} else {
// ...mount the last thing we found
mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
append_mount_options(&(mtcur->mnt_opts), cmdopts);
resolve_mount_spec(&mtpair->mnt_fsname);
rc = singlemount(mtcur, /*ignore_busy:*/ 0);
if (ENABLE_FEATURE_CLEAN_UP)
free(mtcur->mnt_opts);
//}
}
//ret:
if (ENABLE_FEATURE_CLEAN_UP)
endmntent(fstab);
if (ENABLE_FEATURE_CLEAN_UP) {
free(storage_path);
free(cmdopts);
}
//TODO: exitcode should be ORed mask of (from "man mount"):
// 0 success
// 1 incorrect invocation or permissions
// 2 system error (out of memory, cannot fork, no more loop devices)
// 4 internal mount bug or missing nfs support in mount
// 8 user interrupt
//16 problems writing or locking /etc/mtab
//32 mount failure
//64 some mount succeeded
return rc;
}
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