source/client/umount.cifs.c

   1 /*
   2    Unmount utility program for Linux CIFS VFS (virtual filesystem) client
   3    Copyright (C) 2005 Steve French  (sfrench@us.ibm.com)
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  18
  19 #ifndef _GNU_SOURCE
  20 #define _GNU_SOURCE
  21 #endif
  22
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25 #include <unistd.h>
  26 #include <ctype.h>
  27 #include <sys/types.h>
  28 #include <sys/mount.h>
  29 #include <sys/ioctl.h>
  30 #include <sys/stat.h>
  31 #include <fcntl.h>
  32 #include <getopt.h>
  33 #include <errno.h>
  34 #include <string.h>
  35 #include <mntent.h>
  36
  37 #define UNMOUNT_CIFS_VERSION_MAJOR "0"
  38 #define UNMOUNT_CIFS_VERSION_MINOR "1"
  39
  40 #ifndef UNMOUNT_CIFS_VENDOR_SUFFIX
  41 #define UNMOUNT_CIFS_VENDOR_SUFFIX ""
  42 #endif
  43
  44 #ifndef MNT_DETACH
  45 #define MNT_DETACH 0x02
  46 #endif
  47
  48 #ifndef MNT_EXPIRE
  49 #define MNT_EXPIRE 0x04
  50 #endif
  51
  52 #define CIFS_IOC_CHECKUMOUNT _IOR('u', 2, int)
  53
  54 static struct option longopts[] = {
  55         { "all", 0, NULL, 'a' },
  56         { "help",0, NULL, 'h' },
  57         { "read-only", 0, NULL, 'r' },
  58         { "ro", 0, NULL, 'r' },
  59         { "verbose", 0, NULL, 'v' },
  60         { "version", 0, NULL, 'V' },
  61         { "expire", 0, NULL, 'e' },
  62         { "force", 0, 0, 'f' },
  63         { "lazy", 0, 0, 'l' },
  64         { "no-mtab", 0, 0, 'n' },
  65         { NULL, 0, NULL, 0 }
  66 };
  67
  68 char * thisprogram;
  69 int verboseflg = 0;
  70
  71 static void umount_cifs_usage(void)
  72 {
  73         printf("\nUsage:  %s <remotetarget> <dir>\n", thisprogram);
  74         printf("\nUnmount the specified directory\n");
  75         printf("\nLess commonly used options:");
  76         printf("\n\t-r\tIf mount fails, retry with readonly remount.");
  77         printf("\n\t-n\tDo not write to mtab.");
  78         printf("\n\t-f\tAttempt a forced unmount, even if the fs is busy.");
  79         printf("\n\t-l\tAttempt lazy unmount, Unmount now, cleanup later.");
  80         printf("\n\t-v\tEnable verbose mode (may be useful for debugging).");
  81         printf("\n\t-h\tDisplay this help.");
  82         printf("\n\nOptions are described in more detail in the manual page");
  83         printf("\n\tman 8 umount.cifs\n");
  84         printf("\nTo display the version number of the cifs umount utility:");
  85         printf("\n\t%s -V\n",thisprogram);
  86 }
  87
  88 static int umount_check_perm(char * dir)
  89 {
  90         int fileid;
  91         int rc;
  92
  93         /* presumably can not chdir into the target as we do on mount */
  94
  95         fileid = open(dir, O_RDONLY | O_DIRECTORY | O_NOFOLLOW, 0);
  96
  97         /* check if fileid valid if fileid == -1 BB FIXME */
  98
  99         rc = ioctl(fileid, CIFS_IOC_CHECKUMOUNT, NULL);
 100
 101         if(verboseflg)
 102                 printf("ioctl returned %d with errno %d\n",rc,errno);
 103
 104         close(fileid);
 105
 106         return rc;
 107 }
 108
 109 int main(int argc, char ** argv)
 110 {
 111         int c;
 112         int rc;
 113         int flags = 0;
 114         int nomtab = 0;
 115         int retry_remount = 0;
 116         struct mntent mountent;
 117         char * mountpoint;
 118         FILE * pmntfile;
 119
 120         if(argc && argv) {
 121                 thisprogram = argv[0];
 122         } else {
 123                 umount_cifs_usage();
 124                 return -EINVAL;
 125         }
 126
 127         if(argc < 2) {
 128                 umount_cifs_usage();
 129                 return -EINVAL;
 130         }
 131
 132         if(thisprogram == NULL)
 133                 thisprogram = "umount.cifs";
 134
 135         /* add sharename in opts string as unc= parm */
 136
 137         while ((c = getopt_long (argc, argv, "afhilnrvV",
 138                          longopts, NULL)) != -1) {
 139                 switch (c) {
 140 /* No code to do the following  option yet */
 141 /*              case 'a':
 142                         ++umount_all;
 143                         break; */
 144                 case '?':
 145                 case 'h':   /* help */
 146                         umount_cifs_usage();
 147                         exit(1);
 148                 case 'n':
 149                         ++nomtab;
 150                         break;
 151                 case 'f':
 152                         flags |= MNT_FORCE;
 153                         break;
 154                 case 'l':
 155                         flags |= MNT_DETACH; /* lazy unmount */
 156                         break;
 157                 case 'e':
 158                         flags |= MNT_EXPIRE; /* gradually timeout */
 159                         break;
 160                 case 'r':
 161                         ++retry_remount;
 162                         break;
 163                 case 'v':
 164                         ++verboseflg;
 165                         break;
 166                 case 'V':
 167                         printf ("umount.cifs version: %s.%s%s\n",
 168                                 UNMOUNT_CIFS_VERSION_MAJOR,
 169                                 UNMOUNT_CIFS_VERSION_MINOR,
 170                                 UNMOUNT_CIFS_VENDOR_SUFFIX);
 171                         exit (0);
 172                 default:
 173                         printf("unknown unmount option %c\n",c);
 174                         umount_cifs_usage();
 175                         exit(1);
 176                 }
 177         }
 178
 179         /* move past the umount options */
 180         argv += optind;
 181         argc -= optind;
 182
 183         mountpoint = argv[0];
 184
 185         if((argc < 1) || (argv[0] == NULL)) {
 186                 printf("\nMissing name of unmount directory\n");
 187                 umount_cifs_usage();
 188                 return -EINVAL;
 189         }
 190
 191         if(verboseflg)
 192                 printf("optind %d unmount dir %s\n",optind, mountpoint);
 193
 194         /* check if running effectively root */
 195         if(geteuid() != 0)
 196                 printf("Trying to unmount when %s not installed suid\n",thisprogram);
 197
 198         /* fixup path if needed */
 199
 200         /* check if our uid was the one who mounted */
 201         rc = umount_check_perm(mountpoint);
 202         if (rc) {
 203                 return rc;
 204         }
 205
 206         if(umount2(mountpoint, flags)) {
 207         /* remember to kill daemon on error */
 208
 209                 switch (errno) {
 210                 case 0:
 211                         printf("mount failed but no error number set\n");
 212                         break;
 213                 default:
 214
 215                         printf("mount error %d = %s\n",errno,strerror(errno));
 216                 }
 217                 printf("Refer to the umount.cifs(8) manual page (e.g.man 8 umount.cifs)\n");
 218                 return -1;
 219         } else {
 220                 pmntfile = setmntent(MOUNTED, "a+");
 221                 if(pmntfile) {
 222 /*                      mountent.mnt_fsname = share_name;
 223                         mountent.mnt_dir = mountpoint;
 224                         mountent.mnt_type = "cifs";
 225                         mountent.mnt_opts = malloc(220);
 226                         if(mountent.mnt_opts) {
 227                                 char * mount_user = getusername();
 228                                 memset(mountent.mnt_opts,0,200);
 229                                 if(flags & MS_RDONLY)
 230                                         strcat(mountent.mnt_opts,"ro");
 231                                 else
 232                                         strcat(mountent.mnt_opts,"rw");
 233                                 if(flags & MS_MANDLOCK)
 234                                         strcat(mountent.mnt_opts,",mand");
 235                                 else
 236                                         strcat(mountent.mnt_opts,",nomand");
 237                                 if(flags & MS_NOEXEC)
 238                                         strcat(mountent.mnt_opts,",noexec");
 239                                 if(flags & MS_NOSUID)
 240                                         strcat(mountent.mnt_opts,",nosuid");
 241                                 if(flags & MS_NODEV)
 242                                         strcat(mountent.mnt_opts,",nodev");
 243                                 if(flags & MS_SYNCHRONOUS)
 244                                         strcat(mountent.mnt_opts,",synch");
 245                                 if(mount_user) {
 246                                         if(getuid() != 0) {
 247                                                 strcat(mountent.mnt_opts,",user=");
 248                                                 strcat(mountent.mnt_opts,mount_user);
 249                                         }
 250                                         free(mount_user);
 251                                 }
 252                         }
 253                         mountent.mnt_freq = 0;
 254                         mountent.mnt_passno = 0;
 255                         rc = addmntent(pmntfile,&mountent);
 256                         endmntent(pmntfile);
 257                         if(mountent.mnt_opts)
 258                                 free(mountent.mnt_opts);*/
 259                 } else {
 260                     printf("could not update mount table\n");
 261                 }
 262         }
 263
 264         return 0;
 265 }
 266