mount: support user mounts if CONFIG_DESKTOP

This commit is contained in:
Denis Vlasenko 2006-10-16 22:39:51 +00:00
parent f46be09106
commit 13c5a6832f
3 changed files with 68 additions and 28 deletions

View File

@ -46,6 +46,10 @@
# define _BB_DIR_USR_SBIN _BB_DIR_SBIN
#endif
// _BB_SUID_ALWAYS: will complain if busybox isn't suid
// and is run by non-root (applet_main() will not be called at all)
// _BB_SUID_NEVER: will drop suid prior to applet_main()
// _BB_SUID_MAYBE: neither of the above
USE_TEST(APPLET_NOUSAGE([, test, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
USE_TEST(APPLET_NOUSAGE([[, test, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
@ -198,7 +202,7 @@ USE_MKSWAP(APPLET(mkswap, _BB_DIR_SBIN, _BB_SUID_NEVER))
USE_MKTEMP(APPLET(mktemp, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_MODPROBE(APPLET(modprobe, _BB_DIR_SBIN, _BB_SUID_NEVER))
USE_MORE(APPLET(more, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_MOUNT(APPLET(mount, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_MOUNT(APPLET(mount, _BB_DIR_BIN, USE_DESKTOP(_BB_SUID_MAYBE) SKIP_DESKTOP(_BB_SUID_NEVER)))
USE_MOUNTPOINT(APPLET(mountpoint, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_MSH(APPLET_NOUSAGE(msh, msh, _BB_DIR_BIN, _BB_SUID_NEVER))
USE_MT(APPLET(mt, _BB_DIR_BIN, _BB_SUID_NEVER))

View File

@ -32,8 +32,19 @@
// Not real flags, but we want to be able to check for this.
#define MOUNT_NOAUTO (1<<29)
#define MOUNT_SWAP (1<<30)
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 */
@ -53,6 +64,8 @@ struct {
{"quiet", 0},
{"noauto", MOUNT_NOAUTO},
{"swap", MOUNT_SWAP},
USE_DESKTOP({"user", MOUNT_USERS},)
USE_DESKTOP({"users", MOUNT_USERS},)
)
USE_FEATURE_MOUNT_FLAGS(
@ -106,7 +119,8 @@ static void append_mount_options(char **oldopts, char *newopts)
if (p) len = p - newopts;
p = *oldopts;
while (1) {
if (!strncmp(p,newopts,len) && (p[len]==',' || p[len]==0))
if (!strncmp(p, newopts, len)
&& (p[len]==',' || p[len]==0))
goto skip;
p = strchr(p,',');
if(!p) break;
@ -1422,6 +1436,8 @@ report_error:
// Parse options, if necessary parse fstab/mtab, and call singlemount for
// each directory to be mounted.
const char must_be_root[] = "you must be root";
int mount_main(int argc, char **argv)
{
enum { OPT_ALL = 0x10 };
@ -1433,6 +1449,8 @@ int mount_main(int argc, char **argv)
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. */
@ -1475,7 +1493,7 @@ int mount_main(int argc, char **argv)
while (getmntent_r(mountTable, mtpair, bb_common_bufsiz1,
sizeof(bb_common_bufsiz1)))
{
// Don't show rootfs.
// Don't show rootfs. FIXME: why??
if (!strcmp(mtpair->mnt_fsname, "rootfs")) continue;
if (!fstype || !strcmp(mtpair->mnt_type, fstype))
@ -1493,6 +1511,8 @@ int mount_main(int argc, char **argv)
// 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;
@ -1502,6 +1522,8 @@ int mount_main(int argc, char **argv)
}
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.
@ -1515,9 +1537,10 @@ int mount_main(int argc, char **argv)
// Open either fstab or mtab
if (i & MS_REMOUNT)
fstabname = "/etc/fstab";
if (i & MS_REMOUNT) {
fstabname = bb_path_mtab_file;
else fstabname = "/etc/fstab";
}
fstab = setmntent(fstabname, "r");
if (!fstab)
bb_perror_msg_and_die("cannot read %s", fstabname);
@ -1544,9 +1567,15 @@ int mount_main(int argc, char **argv)
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 = mtnext;
mtcur->mnt_opts = xstrdup(mtcur->mnt_opts);
append_mount_options(&(mtcur->mnt_opts), cmdopts);
rc = singlemount(mtcur, 0);
@ -1576,8 +1605,9 @@ int mount_main(int argc, char **argv)
// If we're mounting all.
} else {
// Do we need to match a filesystem type?
// TODO: support "-t type1,type2"; "-t notype1,type2"
if (fstype && strcmp(mtcur->mnt_type, fstype)) continue;
// Skip noauto and swap anyway.
@ -1585,6 +1615,12 @@ int mount_main(int argc, char **argv)
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.
if (singlemount(mtcur, 1)) {