--- /dev/null
+/*
+ Unmount utility program for Linux CIFS VFS (virtual filesystem) client
+ Copyright (C) 2005 Steve French (sfrench@us.ibm.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., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/vfs.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <errno.h>
+#include <string.h>
+#include <mntent.h>
+#include <fstab.h>
+
+#define UNMOUNT_CIFS_VERSION_MAJOR "0"
+#define UNMOUNT_CIFS_VERSION_MINOR "5"
+
+#ifndef UNMOUNT_CIFS_VENDOR_SUFFIX
+#define UNMOUNT_CIFS_VENDOR_SUFFIX ""
+#endif
+
+#ifndef MNT_DETACH
+#define MNT_DETACH 0x02
+#endif
+
+#ifndef MNT_EXPIRE
+#define MNT_EXPIRE 0x04
+#endif
+
+#ifndef MOUNTED_LOCK
+#define MOUNTED_LOCK "/etc/mtab~"
+#endif
+#ifndef MOUNTED_TEMP
+#define MOUNTED_TEMP "/etc/mtab.tmp"
+#endif
+
+#define CIFS_IOC_CHECKUMOUNT _IO(0xCF, 2)
+#define CIFS_MAGIC_NUMBER 0xFF534D42 /* the first four bytes of SMB PDU */
+
+static struct option longopts[] = {
+ { "all", 0, NULL, 'a' },
+ { "help",0, NULL, 'h' },
+ { "read-only", 0, NULL, 'r' },
+ { "ro", 0, NULL, 'r' },
+ { "verbose", 0, NULL, 'v' },
+ { "version", 0, NULL, 'V' },
+ { "expire", 0, NULL, 'e' },
+ { "force", 0, 0, 'f' },
+ { "lazy", 0, 0, 'l' },
+ { "no-mtab", 0, 0, 'n' },
+ { NULL, 0, NULL, 0 }
+};
+
+char * thisprogram;
+int verboseflg = 0;
+
+static void umount_cifs_usage(void)
+{
+ printf("\nUsage: %s <remotetarget> <dir>\n", thisprogram);
+ printf("\nUnmount the specified directory\n");
+ printf("\nLess commonly used options:");
+ printf("\n\t-r\tIf mount fails, retry with readonly remount.");
+ printf("\n\t-n\tDo not write to mtab.");
+ printf("\n\t-f\tAttempt a forced unmount, even if the fs is busy.");
+ printf("\n\t-l\tAttempt lazy unmount, Unmount now, cleanup later.");
+ printf("\n\t-v\tEnable verbose mode (may be useful for debugging).");
+ printf("\n\t-h\tDisplay this help.");
+ printf("\n\nOptions are described in more detail in the manual page");
+ printf("\n\tman 8 umount.cifs\n");
+ printf("\nTo display the version number of the cifs umount utility:");
+ printf("\n\t%s -V\n",thisprogram);
+ printf("\nInvoking the umount utility on cifs mounts, can execute");
+ printf(" /sbin/umount.cifs (if present and umount -i is not specified.\n");
+}
+
+static int umount_check_perm(char * dir)
+{
+ int fileid;
+ int rc;
+
+ /* allow root to unmount, no matter what */
+ if(getuid() == 0)
+ return 0;
+
+ /* presumably can not chdir into the target as we do on mount */
+ fileid = open(dir, O_RDONLY | O_DIRECTORY | O_NOFOLLOW, 0);
+ if(fileid == -1) {
+ if(verboseflg)
+ printf("error opening mountpoint %d %s",errno,strerror(errno));
+ return errno;
+ }
+
+ rc = ioctl(fileid, CIFS_IOC_CHECKUMOUNT, NULL);
+
+ if(verboseflg)
+ printf("ioctl returned %d with errno %d %s\n",rc,errno,strerror(errno));
+
+ if(rc == ENOTTY) {
+ printf("user unmounting via %s is an optional feature of",thisprogram);
+ printf(" the cifs filesystem driver (cifs.ko)");
+ printf("\n\tand requires cifs.ko version 1.32 or later\n");
+ } else if (rc > 0)
+ printf("user unmount of %s failed with %d %s\n",dir,errno,strerror(errno));
+ close(fileid);
+
+ return rc;
+}
+
+int lock_mtab(void)
+{
+ int rc;
+
+ rc = mknod(MOUNTED_LOCK , 0600, 0);
+ if(rc == -1)
+ printf("\ngetting lock file %s failed with %s\n",MOUNTED_LOCK,
+ strerror(errno));
+
+ return rc;
+
+}
+
+void unlock_mtab(void)
+{
+ unlink(MOUNTED_LOCK);
+}
+
+int remove_from_mtab(char * mountpoint)
+{
+ int rc;
+ int num_matches;
+ FILE * org_fd;
+ FILE * new_fd;
+ struct mntent * mount_entry;
+
+ /* Do we need to check if it is a symlink to e.g. /proc/mounts
+ in which case we probably do not want to update it? */
+
+ /* Do we first need to check if it is writable? */
+
+ if (lock_mtab()) {
+ printf("Mount table locked\n");
+ return -EACCES;
+ }
+
+ if(verboseflg)
+ printf("attempting to remove from mtab\n");
+
+ org_fd = setmntent(MOUNTED, "r");
+
+ if(org_fd == NULL) {
+ printf("Can not open %s\n",MOUNTED);
+ unlock_mtab();
+ return -EIO;
+ }
+
+ new_fd = setmntent(MOUNTED_TEMP,"w");
+ if(new_fd == NULL) {
+ printf("Can not open temp file %s", MOUNTED_TEMP);
+ endmntent(org_fd);
+ unlock_mtab();
+ return -EIO;
+ }
+
+ /* BB fix so we only remove the last entry that matches BB */
+ num_matches = 0;
+ while((mount_entry = getmntent(org_fd)) != NULL) {
+ if(strcmp(mount_entry->mnt_dir, mountpoint) == 0) {
+ num_matches++;
+ }
+ }
+ if(verboseflg)
+ printf("%d matching entries in mount table\n", num_matches);
+
+ /* Is there a better way to seek back to the first entry in mtab? */
+ endmntent(org_fd);
+ org_fd = setmntent(MOUNTED, "r");
+
+ if(org_fd == NULL) {
+ printf("Can not open %s\n",MOUNTED);
+ unlock_mtab();
+ return -EIO;
+ }
+
+ while((mount_entry = getmntent(org_fd)) != NULL) {
+ if(strcmp(mount_entry->mnt_dir, mountpoint) != 0) {
+ addmntent(new_fd, mount_entry);
+ } else {
+ if(num_matches != 1) {
+ addmntent(new_fd, mount_entry);
+ num_matches--;
+ } else if(verboseflg)
+ printf("entry not copied (ie entry is removed)\n");
+ }
+ }
+
+ if(verboseflg)
+ printf("done updating tmp file\n");
+ rc = fchmod (fileno (new_fd), S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
+ if(rc < 0) {
+ printf("error %s changing mode of %s\n", strerror(errno),
+ MOUNTED_TEMP);
+ }
+ endmntent(new_fd);
+
+ rc = rename(MOUNTED_TEMP, MOUNTED);
+
+ if(rc < 0) {
+ printf("failure %s renaming %s to %s\n",strerror(errno),
+ MOUNTED_TEMP, MOUNTED);
+ unlock_mtab();
+ return -EIO;
+ }
+
+ unlock_mtab();
+
+ return rc;
+}
+
+int main(int argc, char ** argv)
+{
+ int c;
+ int rc;
+ int flags = 0;
+ int nomtab = 0;
+ int retry_remount = 0;
+ struct statfs statbuf;
+ char * mountpoint;
+
+ if(argc && argv) {
+ thisprogram = argv[0];
+ } else {
+ umount_cifs_usage();
+ return -EINVAL;
+ }
+
+ if(argc < 2) {
+ umount_cifs_usage();
+ return -EINVAL;
+ }
+
+ if(thisprogram == NULL)
+ thisprogram = "umount.cifs";
+
+ /* add sharename in opts string as unc= parm */
+
+ while ((c = getopt_long (argc, argv, "afhilnrvV",
+ longopts, NULL)) != -1) {
+ switch (c) {
+/* No code to do the following option yet */
+/* case 'a':
+ ++umount_all;
+ break; */
+ case '?':
+ case 'h': /* help */
+ umount_cifs_usage();
+ exit(1);
+ case 'n':
+ ++nomtab;
+ break;
+ case 'f':
+ flags |= MNT_FORCE;
+ break;
+ case 'l':
+ flags |= MNT_DETACH; /* lazy unmount */
+ break;
+ case 'e':
+ flags |= MNT_EXPIRE; /* gradually timeout */
+ break;
+ case 'r':
+ ++retry_remount;
+ break;
+ case 'v':
+ ++verboseflg;
+ break;
+ case 'V':
+ printf ("umount.cifs version: %s.%s%s\n",
+ UNMOUNT_CIFS_VERSION_MAJOR,
+ UNMOUNT_CIFS_VERSION_MINOR,
+ UNMOUNT_CIFS_VENDOR_SUFFIX);
+ exit (0);
+ default:
+ printf("unknown unmount option %c\n",c);
+ umount_cifs_usage();
+ exit(1);
+ }
+ }
+
+ /* move past the umount options */
+ argv += optind;
+ argc -= optind;
+
+ mountpoint = argv[0];
+
+ if((argc < 1) || (argv[0] == NULL)) {
+ printf("\nMissing name of unmount directory\n");
+ umount_cifs_usage();
+ return -EINVAL;
+ }
+
+ if(verboseflg)
+ printf("optind %d unmount dir %s\n",optind, mountpoint);
+
+ /* check if running effectively root */
+ if(geteuid() != 0) {
+ printf("Trying to unmount when %s not installed suid\n",thisprogram);
+ if(verboseflg)
+ printf("euid = %d\n",geteuid());
+ return -EACCES;
+ }
+
+ /* fixup path if needed */
+
+ /* make sure that this is a cifs filesystem */
+ rc = statfs(mountpoint, &statbuf);
+
+ if(rc || (statbuf.f_type != CIFS_MAGIC_NUMBER)) {
+ printf("This utility only unmounts cifs filesystems.\n");
+ return -EINVAL;
+ }
+
+ /* check if our uid was the one who mounted */
+ rc = umount_check_perm(mountpoint);
+ if (rc) {
+ printf("Not permitted to unmount\n");
+ return rc;
+ }
+
+ if(umount2(mountpoint, flags)) {
+ /* remember to kill daemon on error */
+ switch (errno) {
+ case 0:
+ printf("unmount failed but no error number set\n");
+ break;
+ default:
+ printf("unmount error %d = %s\n",errno,strerror(errno));
+ }
+ printf("Refer to the umount.cifs(8) manual page (man 8 umount.cifs)\n");
+ return -1;
+ } else {
+ if(verboseflg)
+ printf("umount2 succeeded\n");
+ if(nomtab == 0)
+ remove_from_mtab(mountpoint);
+ }
+
+ return 0;
+}
+
projects / samba / blobdiff