hush/mount.c
Matt Kraai 322ae93a5e Fix calls to {m,c,re}alloc so that they use x{m,c,re}alloc instead of
segfaulting or handling errors the same way themselves.
2000-09-13 02:46:14 +00:00

514 lines
13 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini mount implementation for busybox
*
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* 3/21/1999 Charles P. Wright <cpwright@cpwright.com>
* searches through fstab when -a is passed
* will try mounting stuff with all fses when passed -t auto
*
* 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab.
*
* 1999-10-07 Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
* Rewrite of a lot of code. Removed mtab usage (I plan on
* putting it back as a compile-time option some time),
* major adjustments to option parsing, and some serious
* dieting all around.
*
* 1999-11-06 mtab suppport is back - andersee
*
* 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's
* mount to add loop support.
*
* 2000-04-30 Dave Cinege <dcinege@psychosis.com>
* Rewrote fstab while loop and lower mount section. Can now do
* single mounts from fstab. Can override fstab options for single
* mount. Common mount_one call for single mounts and 'all'. Fixed
* mtab updating and stale entries. Removed 'remount' default.
*
*/
#include "internal.h"
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <mntent.h>
#include <ctype.h>
#if defined BB_FEATURE_USE_DEVPS_PATCH
#include <linux/devmtab.h> /* For Erik's nifty devmtab device driver */
#endif
#define MS_MGC_VAL 0xc0ed0000 /* Magic number indicatng "new" flags */
#define MS_RDONLY 1 /* Mount read-only */
#define MS_NOSUID 2 /* Ignore suid and sgid bits */
#define MS_NODEV 4 /* Disallow access to device special files */
#define MS_NOEXEC 8 /* Disallow program execution */
#define MS_SYNCHRONOUS 16 /* Writes are synced at once */
#define MS_REMOUNT 32 /* Alter flags of a mounted FS */
#define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
#define S_QUOTA 128 /* Quota initialized for file/directory/symlink */
#define S_APPEND 256 /* Append-only file */
#define S_IMMUTABLE 512 /* Immutable file */
#define MS_NOATIME 1024 /* Do not update access times. */
#define MS_NODIRATIME 2048 /* Do not update directory access times */
#if defined BB_FEATURE_MOUNT_LOOP
#include <fcntl.h>
#include <sys/ioctl.h>
static int use_loop = FALSE;
#endif
extern int mount (__const char *__special_file, __const char *__dir,
__const char *__fstype, unsigned long int __rwflag,
__const void *__data);
extern int umount (__const char *__special_file);
extern int umount2 (__const char *__special_file, int __flags);
extern const char mtab_file[]; /* Defined in utility.c */
struct mount_options {
const char *name;
unsigned long and;
unsigned long or;
};
static const struct mount_options mount_options[] = {
{"async", ~MS_SYNCHRONOUS, 0},
{"atime", ~0, ~MS_NOATIME},
{"defaults", ~0, 0},
{"dev", ~MS_NODEV, 0},
{"diratime", ~0, ~MS_NODIRATIME},
{"exec", ~MS_NOEXEC, 0},
{"noatime", ~0, MS_NOATIME},
{"nodev", ~0, MS_NODEV},
{"nodiratime", ~0, MS_NODIRATIME},
{"noexec", ~0, MS_NOEXEC},
{"nosuid", ~0, MS_NOSUID},
{"remount", ~0, MS_REMOUNT},
{"ro", ~0, MS_RDONLY},
{"rw", ~MS_RDONLY, 0},
{"suid", ~MS_NOSUID, 0},
{"sync", ~0, MS_SYNCHRONOUS},
{0, 0, 0}
};
static int
do_mount(char *specialfile, char *dir, char *filesystemtype,
long flags, void *string_flags, int useMtab, int fakeIt,
char *mtab_opts)
{
int status = 0;
char *lofile = NULL;
if (fakeIt == FALSE)
{
#if defined BB_FEATURE_MOUNT_LOOP
if (use_loop==TRUE) {
int loro = flags & MS_RDONLY;
char *lofile = specialfile;
specialfile = find_unused_loop_device();
if (specialfile == NULL) {
errorMsg("Could not find a spare loop device\n");
return (FALSE);
}
if (set_loop(specialfile, lofile, 0, &loro)) {
errorMsg("Could not setup loop device\n");
return (FALSE);
}
if (!(flags & MS_RDONLY) && loro) { /* loop is ro, but wanted rw */
errorMsg("WARNING: loop device is read-only\n");
flags &= ~MS_RDONLY;
}
}
#endif
status = mount(specialfile, dir, filesystemtype, flags, string_flags);
}
/* If the mount was sucessful, do anything needed, then return TRUE */
if (status == 0 || fakeIt==TRUE) {
#if defined BB_MTAB
if (useMtab == TRUE) {
erase_mtab(specialfile); // Clean any stale entries
write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
}
#endif
return (TRUE);
}
/* Bummer. mount failed. Clean up */
#if defined BB_FEATURE_MOUNT_LOOP
if (lofile != NULL) {
del_loop(specialfile);
}
#endif
if (errno == EPERM) {
fatalError("permission denied. Are you root?\n");
}
return (FALSE);
}
/* Seperate standard mount options from the nonstandard string options */
static void
parse_mount_options(char *options, int *flags, char *strflags)
{
while (options) {
int gotone = FALSE;
char *comma = strchr(options, ',');
const struct mount_options *f = mount_options;
if (comma)
*comma = '\0';
while (f->name != 0) {
if (strcasecmp(f->name, options) == 0) {
*flags &= f->and;
*flags |= f->or;
gotone = TRUE;
break;
}
f++;
}
#if defined BB_FEATURE_MOUNT_LOOP
if (gotone == FALSE && !strcasecmp("loop", options)) { /* loop device support */
use_loop = TRUE;
gotone = TRUE;
}
#endif
if (*strflags && strflags != '\0' && gotone == FALSE) {
char *temp = strflags;
temp += strlen(strflags);
*temp++ = ',';
*temp++ = '\0';
}
if (gotone == FALSE)
strcat(strflags, options);
if (comma) {
*comma = ',';
options = ++comma;
} else {
break;
}
}
}
int
mount_one(char *blockDevice, char *directory, char *filesystemType,
unsigned long flags, char *string_flags, int useMtab, int fakeIt,
char *mtab_opts, int whineOnErrors)
{
int status = 0;
#if defined BB_FEATURE_USE_PROCFS
char buf[255];
if (strcmp(filesystemType, "auto") == 0) {
FILE *f = fopen("/proc/filesystems", "r");
if (f == NULL)
return (FALSE);
while (fgets(buf, sizeof(buf), f) != NULL) {
filesystemType = buf;
if (*filesystemType == '\t') { // Not a nodev filesystem
// Add NULL termination to each line
while (*filesystemType && *filesystemType != '\n')
filesystemType++;
*filesystemType = '\0';
filesystemType = buf;
filesystemType++; // hop past tab
status = do_mount(blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags,
useMtab, fakeIt, mtab_opts);
if (status == TRUE)
break;
}
}
fclose(f);
} else
#endif
#if defined BB_FEATURE_USE_DEVPS_PATCH
if (strcmp(filesystemType, "auto") == 0) {
int fd, i, numfilesystems;
char device[] = "/dev/mtab";
struct k_fstype *fslist;
/* open device */
fd = open(device, O_RDONLY);
if (fd < 0)
fatalError("open failed for `%s': %s\n", device, strerror (errno));
/* How many filesystems? We need to know to allocate enough space */
numfilesystems = ioctl (fd, DEVMTAB_COUNT_FILESYSTEMS);
if (numfilesystems<0)
fatalError("\nDEVMTAB_COUNT_FILESYSTEMS: %s\n", strerror (errno));
fslist = (struct k_fstype *) xcalloc ( numfilesystems, sizeof(struct k_fstype));
/* Grab the list of available filesystems */
status = ioctl (fd, DEVMTAB_GET_FILESYSTEMS, fslist);
if (status<0)
fatalError("\nDEVMTAB_GET_FILESYSTEMS: %s\n", strerror (errno));
/* Walk the list trying to mount filesystems
* that do not claim to be nodev filesystems */
for( i = 0 ; i < numfilesystems ; i++) {
if (fslist[i].mnt_nodev)
continue;
status = do_mount(blockDevice, directory, fslist[i].mnt_type,
flags | MS_MGC_VAL, string_flags,
useMtab, fakeIt, mtab_opts);
if (status == TRUE)
break;
}
free( fslist);
close(fd);
} else
#endif
{
status = do_mount(blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags, useMtab,
fakeIt, mtab_opts);
}
if (status == FALSE) {
if (whineOnErrors == TRUE) {
errorMsg("Mounting %s on %s failed: %s\n",
blockDevice, directory, strerror(errno));
}
return (FALSE);
}
return (TRUE);
}
extern int mount_main(int argc, char **argv)
{
char string_flags_buf[1024] = "";
char *string_flags = string_flags_buf;
char *extra_opts = string_flags_buf;
int flags = 0;
char *filesystemType = "auto";
char *device = NULL;
char *directory = NULL;
int all = FALSE;
int fakeIt = FALSE;
int useMtab = TRUE;
int i;
int rc = FALSE;
int fstabmount = FALSE;
#if defined BB_FEATURE_USE_DEVPS_PATCH
if (argc == 1) {
int fd, i, numfilesystems;
char device[] = "/dev/mtab";
struct k_mntent *mntentlist;
/* open device */
fd = open(device, O_RDONLY);
if (fd < 0)
fatalError("open failed for `%s': %s\n", device, strerror (errno));
/* How many mounted filesystems? We need to know to
* allocate enough space for later... */
numfilesystems = ioctl (fd, DEVMTAB_COUNT_MOUNTS);
if (numfilesystems<0)
fatalError( "\nDEVMTAB_COUNT_MOUNTS: %s\n", strerror (errno));
mntentlist = (struct k_mntent *) xcalloc ( numfilesystems, sizeof(struct k_mntent));
/* Grab the list of mounted filesystems */
if (ioctl (fd, DEVMTAB_GET_MOUNTS, mntentlist)<0)
fatalError( "\nDEVMTAB_GET_MOUNTS: %s\n", strerror (errno));
for( i = 0 ; i < numfilesystems ; i++) {
fprintf( stdout, "%s %s %s %s %d %d\n", mntentlist[i].mnt_fsname,
mntentlist[i].mnt_dir, mntentlist[i].mnt_type,
mntentlist[i].mnt_opts, mntentlist[i].mnt_freq,
mntentlist[i].mnt_passno);
}
#ifdef BB_FEATURE_CLEAN_UP
/* Don't bother to close files or free memory. Exit
* does that automagically, so we can save a few bytes */
free( mntentlist);
close(fd);
#endif
exit(TRUE);
}
#else
if (argc == 1) {
FILE *mountTable = setmntent(mtab_file, "r");
if (mountTable) {
struct mntent *m;
while ((m = getmntent(mountTable)) != 0) {
char *blockDevice = m->mnt_fsname;
if (strcmp(blockDevice, "/dev/root") == 0) {
find_real_root_device_name( blockDevice);
}
printf("%s on %s type %s (%s)\n", blockDevice, m->mnt_dir,
m->mnt_type, m->mnt_opts);
}
endmntent(mountTable);
} else {
perror(mtab_file);
}
exit(TRUE);
}
#endif
/* Parse options */
i = --argc;
argv++;
while (i > 0 && **argv) {
if (**argv == '-') {
char *opt = *argv;
while (i > 0 && *++opt)
switch (*opt) {
case 'o':
if (--i == 0) {
goto goodbye;
}
parse_mount_options(*(++argv), &flags, string_flags);
break;
case 'r':
flags |= MS_RDONLY;
break;
case 't':
if (--i == 0) {
goto goodbye;
}
filesystemType = *(++argv);
break;
case 'w':
flags &= ~MS_RDONLY;
break;
case 'a':
all = TRUE;
break;
case 'f':
fakeIt = TRUE;
break;
#ifdef BB_MTAB
case 'n':
useMtab = FALSE;
break;
#endif
case 'v':
break; /* ignore -v */
case 'h':
case '-':
goto goodbye;
}
} else {
if (device == NULL)
device = *argv;
else if (directory == NULL)
directory = *argv;
else {
goto goodbye;
}
}
i--;
argv++;
}
if (all == TRUE || directory == NULL) {
struct mntent *m;
FILE *f = setmntent("/etc/fstab", "r");
fstabmount = TRUE;
if (f == NULL)
fatalError( "\nCannot read /etc/fstab: %s\n", strerror (errno));
while ((m = getmntent(f)) != NULL) {
if (all == FALSE && directory == NULL && (
(strcmp(device, m->mnt_fsname) != 0) &&
(strcmp(device, m->mnt_dir) != 0) ) ) {
continue;
}
if (all == TRUE && ( // If we're mounting 'all'
(strstr(m->mnt_opts, "noauto")) || // and the file system isn't noauto,
(strstr(m->mnt_type, "swap")) || // and isn't swap or nfs, then mount it
(strstr(m->mnt_type, "nfs")) ) ) {
continue;
}
if (all == TRUE || flags == 0) { // Allow single mount to override fstab flags
flags = 0;
*string_flags = '\0';
parse_mount_options(m->mnt_opts, &flags, string_flags);
}
device = strdup(m->mnt_fsname);
directory = strdup(m->mnt_dir);
filesystemType = strdup(m->mnt_type);
singlemount:
#ifdef BB_NFSMOUNT
if (strchr(device, ':') != NULL)
filesystemType = "nfs";
if (strcmp(filesystemType, "nfs") == 0) {
rc = nfsmount (device, directory, &flags,
&extra_opts, &string_flags, 1);
if ( rc != 0) {
fatalError("nfsmount failed: %s\n", strerror(errno));
rc = FALSE;
}
} else
#endif
rc = mount_one(device, directory, filesystemType, flags,
string_flags, useMtab, fakeIt, extra_opts, TRUE);
if (all == FALSE)
break;
rc = TRUE; // Always return 0 for 'all'
}
if (fstabmount == TRUE)
endmntent(f);
if (all == FALSE && fstabmount == TRUE && directory == NULL)
fprintf(stderr, "Can't find %s in /etc/fstab\n", device);
exit(rc);
}
goto singlemount;
exit(FALSE);
goodbye:
usage(mount_usage);
}