busybox/util-linux/mount.c
Denis Vlasenko 9b49a5ed85 add -fvisibility=hidden to CC flags, mark XXX_main functions
EXTERNALLY_VISIBLE. 5% size reduction of libbusybox.so
2007-10-11 10:05:36 +00:00

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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 tarball for details.
*/
/* 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 "libbb.h"
/* Needed for nfs support only... */
#include <syslog.h>
#include <sys/utsname.h>
#undef TRUE
#undef FALSE
#include <rpc/rpc.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_clnt.h>
#ifndef MS_SILENT
#define MS_SILENT (1 << 15)
#endif
#if defined(__dietlibc__)
/* 16.12.2006, Sampo Kellomaki (sampo@iki.fi)
* dietlibc-0.30 does not have implementation of getmntent_r() */
struct mntent *getmntent_r(FILE* stream, struct mntent* result, char* buffer, int bufsize)
{
struct mntent* ment = getmntent(stream);
memcpy(result, ment, sizeof(struct mntent));
return result;
}
#endif
#define getmntent_buf bb_common_bufsiz1
// 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),
};
// 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 struct {
const char *name;
long flags;
} mount_options[] = {
// MS_FLAGS set a bit. ~MS_FLAGS disable that bit. 0 flags are NOPs.
USE_FEATURE_MOUNT_LOOP(
{"loop", 0},
)
USE_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},
USE_DESKTOP({"user", MOUNT_USERS},)
USE_DESKTOP({"users", MOUNT_USERS},)
)
USE_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},
{"async", ~MS_SYNCHRONOUS},
{"atime", ~MS_NOATIME},
{"noatime", MS_NOATIME},
{"diratime", ~MS_NODIRATIME},
{"nodiratime", MS_NODIRATIME},
{"loud", ~MS_SILENT},
// action flags
{"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_SLAVE|MS_RECURSIVE},
{"runbindable", MS_UNBINDABLE|MS_RECURSIVE},
)
// Always understood.
{"ro", MS_RDONLY}, // vfs flag
{"rw", ~MS_RDONLY}, // vfs flag
{"remount", MS_REMOUNT}, // action flag
};
/* 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 return list of unrecognized options if unrecognized!=NULL */
static int parse_mount_options(char *options, char **unrecognized)
{
int flags = MS_SILENT;
// Loop through options
for (;;) {
int i;
char *comma = strchr(options, ',');
if (comma) *comma = 0;
// Find this option in mount_options
for (i = 0; i < ARRAY_SIZE(mount_options); i++) {
if (!strcasecmp(mount_options[i].name, options)) {
long fl = mount_options[i].flags;
if (fl < 0) flags &= fl;
else flags |= fl;
break;
}
}
// If unrecognized not NULL, append unrecognized mount options */
if (unrecognized && i == ARRAY_SIZE(mount_options)) {
// Add it to strflags, to pass on to kernel
i = *unrecognized ? strlen(*unrecognized) : 0;
*unrecognized = xrealloc(*unrecognized, i+strlen(options)+2);
// Comma separated if it's not the first one
if (i) (*unrecognized)[i++] = ',';
strcpy((*unrecognized)+i, options);
}
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 = 0;
int i;
FILE *f;
for (i = 0; i < 2; i++) {
f = fopen(filesystems[i], "r");
if (!f) continue;
while ((buf = xmalloc_getline(f)) != 0) {
if (!strncmp(buf, "nodev", 5) && 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;
}
static llist_t *fslist;
#if ENABLE_FEATURE_CLEAN_UP
static void delete_block_backed_filesystems(void)
{
llist_free(fslist, free);
}
#else
void delete_block_backed_filesystems(void);
#endif
#if ENABLE_FEATURE_MTAB_SUPPORT
static int useMtab = 1;
static int fakeIt;
#else
#define useMtab 0
#define fakeIt 0
#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, int vfsflags, char *filteropts)
{
int rc = 0;
if (fakeIt) goto mtab;
// Mount, with fallback to read-only if necessary.
for (;;) {
rc = mount(mp->mnt_fsname, mp->mnt_dir, mp->mnt_type,
vfsflags, filteropts);
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 (ENABLE_FEATURE_MTAB_SUPPORT && useMtab && !rc && !(vfsflags & MS_REMOUNT)) {
char *fsname;
FILE *mountTable = setmntent(bb_path_mtab_file, "a+");
int i;
if (!mountTable) {
bb_error_msg("no %s",bb_path_mtab_file);
goto ret;
}
// Add vfs string flags
for (i=0; mount_options[i].flags != MS_REMOUNT; i++)
if (mount_options[i].flags > 0 && (mount_options[i].flags & vfsflags))
append_mount_options(&(mp->mnt_opts), mount_options[i].name);
// Remove trailing / (if any) from directory we mounted on
i = strlen(mp->mnt_dir) - 1;
if (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 = 0;
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.
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 tarball for details.
*
* 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 Mi<4D>kiewicz <misiek@misiek.eu.org>
* - added Native Language Support
*
* Modified by Olaf Kirch and Trond Myklebust for new NFS code,
* plus NFSv3 stuff.
*/
/* 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
#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 */
};
/*
* 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 struct {
int stat;
int errnum;
} nfs_errtbl[] = {
{0,0}, {1,EPERM}, {2,ENOENT}, {5,EIO}, {6,ENXIO}, {13,EACCES}, {17,EEXIST},
{19,ENODEV}, {20,ENOTDIR}, {21,EISDIR}, {22,EINVAL}, {27,EFBIG},
{28,ENOSPC}, {30,EROFS}, {63,ENAMETOOLONG}, {66,ENOTEMPTY}, {69,EDQUOT},
{70,ESTALE}, {71,EREMOTE}, {-1,EIO}
};
static char *nfs_strerror(int status)
{
int i;
for (i = 0; nfs_errtbl[i].stat != -1; i++) {
if (nfs_errtbl[i].stat == status)
return strerror(nfs_errtbl[i].errnum);
}
return xasprintf("unknown nfs status return value: %d", status);
}
static bool_t xdr_fhandle(XDR *xdrs, fhandle objp)
{
if (!xdr_opaque(xdrs, objp, FHSIZE))
return FALSE;
return TRUE;
}
static bool_t xdr_fhstatus(XDR *xdrs, fhstatus *objp)
{
if (!xdr_u_int(xdrs, &objp->fhs_status))
return FALSE;
switch (objp->fhs_status) {
case 0:
if (!xdr_fhandle(xdrs, objp->fhstatus_u.fhs_fhandle))
return FALSE;
break;
default:
break;
}
return TRUE;
}
static bool_t xdr_dirpath(XDR *xdrs, dirpath *objp)
{
if (!xdr_string(xdrs, objp, MNTPATHLEN))
return FALSE;
return TRUE;
}
static bool_t xdr_fhandle3(XDR *xdrs, fhandle3 *objp)
{
if (!xdr_bytes(xdrs, (char **)&objp->fhandle3_val, (unsigned int *) &objp->fhandle3_len, FHSIZE3))
return FALSE;
return TRUE;
}
static bool_t xdr_mountres3_ok(XDR *xdrs, mountres3_ok *objp)
{
if (!xdr_fhandle3(xdrs, &objp->fhandle))
return FALSE;
if (!xdr_array(xdrs, &(objp->auth_flavours.auth_flavours_val), &(objp->auth_flavours.auth_flavours_len), ~0,
sizeof (int), (xdrproc_t) xdr_int))
return FALSE;
return TRUE;
}
static bool_t xdr_mountstat3(XDR *xdrs, mountstat3 *objp)
{
if (!xdr_enum(xdrs, (enum_t *) objp))
return FALSE;
return TRUE;
}
static bool_t xdr_mountres3(XDR *xdrs, mountres3 *objp)
{
if (!xdr_mountstat3(xdrs, &objp->fhs_status))
return FALSE;
switch (objp->fhs_status) {
case MNT_OK:
if (!xdr_mountres3_ok(xdrs, &objp->mountres3_u.mountinfo))
return FALSE;
break;
default:
break;
}
return TRUE;
}
#define MAX_NFSPROT ((nfs_mount_version >= 4) ? 3 : 2)
static smalluint nfs_mount_version;
/*
* 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(2,1,32))
nfs_mount_version = 1;
else if (kernel_version < KERNEL_VERSION(2,2,18) ||
(kernel_version >= KERNEL_VERSION(2,3,0) &&
kernel_version < KERNEL_VERSION(2,3,99)))
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 fd;
int pid = fork();
if (pid < 0) /* error */
return -errno;
if (pid > 0) /* parent */
return 0;
/* child */
fd = xopen(bb_dev_null, O_RDWR);
dup2(fd, 0);
dup2(fd, 1);
dup2(fd, 2);
while (fd > 2) close(fd--);
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)
{
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 int nfsmount(struct mntent *mp, int vfsflags, char *filteropts)
{
CLIENT *mclient;
char *hostname;
char *pathname;
char *mounthost;
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
int bg = 0;
#else
enum { bg = 0 };
#endif
int soft;
int intr;
int posix;
int nocto;
int noac;
int nolock;
int retry;
int tcp;
int mountprog;
int mountvers;
int nfsprog;
int nfsvers;
int retval;
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 > sizeof(struct in_addr)) {
bb_error_msg("got bad hp->h_length");
hp->h_length = sizeof(struct in_addr);
}
memcpy(&server_addr.sin_addr,
hp->h_addr, hp->h_length);
}
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;
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) {
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";
int val = xatoi_u(opteq + 1);
*opteq = '\0';
switch (index_in_strings(options, opt)) {
case 0: // "rsize"
data.rsize = val;
break;
case 1: // "wsize"
data.wsize = val;
break;
case 2: // "timeo"
data.timeo = val;
break;
case 3: // "retrans"
data.retrans = val;
break;
case 4: // "acregmin"
data.acregmin = val;
break;
case 5: // "acregmax"
data.acregmax = val;
break;
case 6: // "acdirmin"
data.acdirmin = val;
break;
case 7: // "acdirmax"
data.acdirmax = val;
break;
case 8: // "actimeo"
data.acregmin = val;
data.acregmax = val;
data.acdirmin = val;
data.acdirmax = val;
break;
case 9: // "retry"
retry = val;
break;
case 10: // "port"
port = val;
break;
case 11: // "mountport"
mountport = val;
break;
case 12: // "mounthost"
mounthost = xstrndup(opteq+1,
strcspn(opteq+1," \t\n\r,"));
break;
case 13: // "mountprog"
mountprog = val;
break;
case 14: // "mountvers"
mountvers = val;
break;
case 15: // "nfsprog"
nfsprog = val;
break;
case 16: // "nfsvers"
case 17: // "vers"
nfsvers = val;
break;
case 18: // "proto"
if (!strncmp(opteq+1, "tcp", 3))
tcp = 1;
else if (!strncmp(opteq+1, "udp", 3))
tcp = 0;
else
bb_error_msg("warning: unrecognized proto= option");
break;
case 19: // "namlen"
if (nfs_mount_version >= 2)
data.namlen = val;
else
bb_error_msg("warning: option namlen is not supported\n");
break;
case 20: // "addr" - ignore
break;
default:
bb_error_msg("unknown nfs mount parameter: %s=%d", opt, val);
goto fail;
}
}
else {
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";
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;
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);
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;
} else {
if (hp->h_length > sizeof(struct in_addr)) {
bb_error_msg("got bad hp->h_length?");
hp->h_length = sizeof(struct in_addr);
}
mount_server_addr.sin_family = AF_INET;
memcpy(&mount_server_addr.sin_addr,
hp->h_addr, hp->h_length);
}
}
}
/*
* 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;
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;
}
}
do_mount: /* perform actual mount */
mp->mnt_type = (char*)"nfs";
retval = mount_it_now(mp, vfsflags, (char*)&data);
goto ret;
fail: /* abort */
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, int 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, vfsflags;
char *loopFile = 0, *filteropts = 0;
llist_t *fl = 0;
struct stat st;
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 = 0;
// Might this be a virtual filesystem?
if (ENABLE_FEATURE_MOUNT_HELPERS
&& (strchr(mp->mnt_fsname,'#'))
) {
char *s, *p, *args[35];
int n = 0;
for (s = p = mp->mnt_fsname; *s && n < 35-3; ++s) {
if (s[0] == '#' && s[1] != '#') {
*s = '\0';
args[n++] = p;
p = s + 1;
}
}
args[n++] = p;
args[n++] = mp->mnt_dir;
args[n] = NULL;
rc = wait4pid(xspawn(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]
) {
len_and_sockaddr *lsa;
char *ip, *dotted;
char *s;
rc = 1;
// Replace '/' with '\' and verify that unc points to "//server/share".
for (s = mp->mnt_fsname; *s; ++s)
if (*s == '/') *s = '\\';
// get server IP
s = strrchr(mp->mnt_fsname, '\\');
if (s <= mp->mnt_fsname+1) goto report_error;
*s = '\0';
lsa = host2sockaddr(mp->mnt_fsname+2, 0);
*s = '\\';
if (!lsa) goto report_error;
// insert ip=... option into string flags.
dotted = xmalloc_sockaddr2dotted_noport(&lsa->sa);
ip = xasprintf("ip=%s", dotted);
parse_mount_options(ip, &filteropts);
// compose new unc '\\server-ip\share'
// (s => slash after hostname)
mp->mnt_fsname = xasprintf("\\\\%s%s", dotted, s);
// lock is required
vfsflags |= MS_MANDLOCK;
mp->mnt_type = (char*)"cifs";
rc = mount_it_now(mp, vfsflags, filteropts);
if (ENABLE_FEATURE_CLEAN_UP) {
free(mp->mnt_fsname);
free(ip);
free(dotted);
free(lsa);
}
goto report_error;
}
// Might this be an NFS filesystem?
if (ENABLE_FEATURE_MOUNT_NFS
&& (!mp->mnt_type || !strcmp(mp->mnt_type, "nfs"))
&& 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("cannot 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;
}
// Parse options, if necessary parse fstab/mtab, and call singlemount for
// each directory to be mounted.
static const char must_be_root[] ALIGN1 = "you must be root";
int mount_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mount_main(int argc, char **argv)
{
enum { OPT_ALL = 0x10 };
char *cmdopts = xstrdup(""), *fstype=0, *storage_path=0;
char *opt_o;
const char *fstabname;
FILE *fstab;
int i, j, rc = 0;
unsigned opt;
struct mntent mtpair[2], *mtcur = mtpair;
SKIP_DESKTOP(const int nonroot = 0;)
USE_DESKTOP( int nonroot = (getuid() != 0);)
/* parse long options, like --bind and --move. Note that -o option
* and --option are synonymous. Yes, this means --remount,rw works. */
for (i = j = 0; i < argc; i++) {
if (argv[i][0] == '-' && argv[i][1] == '-') {
append_mount_options(&cmdopts, argv[i]+2);
} else argv[j++] = argv[i];
}
argv[j] = 0;
argc = j;
// Parse remaining options
opt = getopt32(argv, "o:t:rwanfvsi", &opt_o, &fstype);
if (opt & 0x1) append_mount_options(&cmdopts, opt_o); // -o
//if (opt & 0x2) // -t
if (opt & 0x4) append_mount_options(&cmdopts, "ro"); // -r
if (opt & 0x8) append_mount_options(&cmdopts, "rw"); // -w
//if (opt & 0x10) // -a
if (opt & 0x20) USE_FEATURE_MTAB_SUPPORT(useMtab = 0); // -n
if (opt & 0x40) USE_FEATURE_MTAB_SUPPORT(fakeIt = 1); // -f
//if (opt & 0x80) // -v: verbose (ignore)
//if (opt & 0x100) // -s: sloppy (ignore)
//if (opt & 0x200) // -i: don't call mount.<fstype> (ignore)
argv += optind;
argc -= optind;
// Three or more non-option arguments? Die with a usage message.
if (argc > 2) bb_show_usage();
// If we have no arguments, show currently mounted filesystems
if (!argc) {
if (!(opt & OPT_ALL)) {
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,
sizeof(getmntent_buf)))
{
// Don't show rootfs. FIXME: why??
// util-linux 2.12a happily shows rootfs...
//if (!strcmp(mtpair->mnt_fsname, "rootfs")) continue;
if (!fstype || !strcmp(mtpair->mnt_type, fstype))
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;
}
} else storage_path = bb_simplify_path(argv[0]);
// 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 (argc == 2) {
if (nonroot)
bb_error_msg_and_die(must_be_root);
mtpair->mnt_fsname = argv[0];
mtpair->mnt_dir = argv[1];
mtpair->mnt_type = fstype;
mtpair->mnt_opts = cmdopts;
rc = singlemount(mtpair, 0);
goto clean_up;
}
i = parse_mount_options(cmdopts, 0);
if (nonroot && (i & ~MS_SILENT)) // Non-root users cannot specify flags
bb_error_msg_and_die(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))
) {
rc = mount("", argv[0], "", i, "");
if (rc) bb_simple_perror_msg_and_die(argv[0]);
goto clean_up;
}
// Open either fstab or mtab
fstabname = "/etc/fstab";
if (i & MS_REMOUNT) {
fstabname = bb_path_mtab_file;
}
fstab = setmntent(fstabname, "r");
if (!fstab)
bb_perror_msg_and_die("cannot read %s", fstabname);
// Loop through entries until we find what we're looking for.
memset(mtpair, 0, sizeof(mtpair));
for (;;) {
struct mntent *mtnext = (mtcur==mtpair ? mtpair+1 : mtpair);
// Get next fstab entry
if (!getmntent_r(fstab, mtcur, getmntent_buf
+ (mtcur==mtpair ? sizeof(getmntent_buf)/2 : 0),
sizeof(getmntent_buf)/2))
{
// Were we looking for something specific?
if (argc) {
// If we didn't find anything, complain.
if (!mtnext->mnt_fsname)
bb_error_msg_and_die("can't find %s in %s",
argv[0], fstabname);
mtcur = mtnext;
if (nonroot) {
// fstab must have "users" or "user"
if (!(parse_mount_options(mtcur->mnt_opts, 0) & MOUNT_USERS))
bb_error_msg_and_die(must_be_root);
}
// Mount the last thing we found.
mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
append_mount_options(&(mtcur->mnt_opts), cmdopts);
rc = singlemount(mtcur, 0);
free(mtcur->mnt_opts);
}
goto clean_up;
}
/* If we're trying to mount something specific and this isn't it,
* skip it. Note we must match both the exact text in fstab (ala
* "proc") or a full path from root */
if (argc) {
// Is this what we're looking for?
if (strcmp(argv[0], mtcur->mnt_fsname) &&
strcmp(storage_path, mtcur->mnt_fsname) &&
strcmp(argv[0], mtcur->mnt_dir) &&
strcmp(storage_path, mtcur->mnt_dir)) continue;
// Remember this entry. Something later may have overmounted
// it, and we want the _last_ match.
mtcur = mtnext;
// If we're mounting all.
} else {
// Do we need to match a filesystem type?
if (fstype && match_fstype(mtcur, fstype)) continue;
// Skip noauto and swap anyway.
if (parse_mount_options(mtcur->mnt_opts, 0)
& (MOUNT_NOAUTO | MOUNT_SWAP)) continue;
// No, mount -a won't mount anything,
// even user mounts, for mere humans.
if (nonroot)
bb_error_msg_and_die(must_be_root);
// Mount this thing.
// NFS mounts want this to be xrealloc-able
mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
if (singlemount(mtcur, 1)) {
/* Count number of failed mounts */
rc++;
}
free(mtcur->mnt_opts);
}
}
if (ENABLE_FEATURE_CLEAN_UP) endmntent(fstab);
clean_up:
if (ENABLE_FEATURE_CLEAN_UP) {
free(storage_path);
free(cmdopts);
}
return rc;
}