2 * mount.c -- Linux NFS mount
4 * Copyright (C) 2006 Amit Gud <agud@redhat.com>
6 * - Basic code and wrapper around mount and umount code of NFS.
7 * Based on util-linux/mount/mount.c.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2, or (at your option)
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
23 #include <sys/types.h>
28 #include <sys/mount.h>
29 #include <sys/utsname.h>
37 #include "mount_constants.h"
38 #include "nfs_paths.h"
40 #include "nfs_mount.h"
41 #include "nfs4_mount.h"
42 #include "nfsumount.h"
48 int nfs_mount_data_version;
53 static struct option longopts[] = {
54 { "fake", 0, 0, 'f' },
55 { "help", 0, 0, 'h' },
56 { "no-mtab", 0, 0, 'n' },
57 { "read-only", 0, 0, 'r' },
59 { "verbose", 0, 0, 'v' },
60 { "version", 0, 0, 'V' },
61 { "read-write", 0, 0, 'w' },
63 { "options", 1, 0, 'o' },
67 /* Map from -o and fstab option strings to the flag argument to mount(2). */
69 const char *opt; /* option name */
70 int skip; /* skip in mtab option string */
71 int inv; /* true if flag value should be inverted */
72 int mask; /* flag mask value */
75 static const struct opt_map opt_map[] = {
76 { "defaults", 0, 0, 0 }, /* default options */
77 { "ro", 1, 0, MS_RDONLY }, /* read-only */
78 { "rw", 1, 1, MS_RDONLY }, /* read-write */
79 { "exec", 0, 1, MS_NOEXEC }, /* permit execution of binaries */
80 { "noexec", 0, 0, MS_NOEXEC }, /* don't execute binaries */
81 { "suid", 0, 1, MS_NOSUID }, /* honor suid executables */
82 { "nosuid", 0, 0, MS_NOSUID }, /* don't honor suid executables */
83 { "dev", 0, 1, MS_NODEV }, /* interpret device files */
84 { "nodev", 0, 0, MS_NODEV }, /* don't interpret devices */
85 { "sync", 0, 0, MS_SYNCHRONOUS}, /* synchronous I/O */
86 { "async", 0, 1, MS_SYNCHRONOUS}, /* asynchronous I/O */
87 { "dirsync", 0, 0, MS_DIRSYNC}, /* synchronous directory modifications */
88 { "remount", 0, 0, MS_REMOUNT}, /* Alter flags of mounted FS */
89 { "bind", 0, 0, MS_BIND }, /* Remount part of tree elsewhere */
90 { "rbind", 0, 0, MS_BIND|MS_REC }, /* Idem, plus mounted subtrees */
91 { "auto", 0, 0, MS_DUMMY }, /* Can be mounted using -a */
92 { "noauto", 0, 0, MS_DUMMY }, /* Can only be mounted explicitly */
93 { "users", 1, 0, MS_USERS }, /* Allow ordinary user to mount */
94 { "nousers", 0, 1, MS_DUMMY }, /* Forbid ordinary user to mount */
95 { "user", 1, 0, MS_USER }, /* Allow ordinary user to mount */
96 { "nouser", 0, 1, MS_DUMMY }, /* Forbid ordinary user to mount */
97 { "owner", 0, 0, MS_DUMMY }, /* Let the owner of the device mount */
98 { "noowner", 0, 0, MS_DUMMY }, /* Device owner has no special privs */
99 { "group", 0, 0, MS_DUMMY }, /* Let the group of the device mount */
100 { "nogroup", 0, 0, MS_DUMMY }, /* Device group has no special privs */
101 { "_netdev", 0, 0, MS_DUMMY}, /* Device requires network */
102 { "comment", 0, 0, MS_DUMMY}, /* fstab comment only (kudzu,_netdev)*/
104 /* add new options here */
106 { "sub", 0, 1, MS_NOSUB }, /* allow submounts */
107 { "nosub", 0, 0, MS_NOSUB }, /* don't allow submounts */
110 { "quiet", 0, 0, MS_SILENT }, /* be quiet */
111 { "loud", 0, 1, MS_SILENT }, /* print out messages. */
114 { "mand", 0, 0, MS_MANDLOCK }, /* Allow mandatory locks on this FS */
115 { "nomand", 0, 1, MS_MANDLOCK }, /* Forbid mandatory locks on this FS */
117 { "loop", 1, 0, MS_DUMMY }, /* use a loop device */
119 { "atime", 0, 1, MS_NOATIME }, /* Update access time */
120 { "noatime", 0, 0, MS_NOATIME }, /* Do not update access time */
123 { "diratime", 0, 1, MS_NODIRATIME }, /* Update dir access times */
124 { "nodiratime", 0, 0, MS_NODIRATIME },/* Do not update dir access times */
129 #define MAKE_VERSION(p,q,r) (65536 * (p) + 256 * (q) + (r))
131 int linux_version_code(void)
133 struct utsname my_utsname;
136 if (uname(&my_utsname) == 0) {
137 p = atoi(strtok(my_utsname.release, "."));
138 q = atoi(strtok(NULL, "."));
139 r = atoi(strtok(NULL, "."));
140 return MAKE_VERSION(p,q,r);
146 * Choose the version of the nfs_mount_data structure that is appropriate
147 * for the kernel that is doing the mount.
149 * NFS_MOUNT_VERSION: maximum version supported by these sources
150 * nfs_mount_data_version: maximum version supported by the running kernel
152 static void discover_nfs_mount_data_version(void)
154 int kernel_version = linux_version_code();
156 if (kernel_version) {
157 if (kernel_version < MAKE_VERSION(2, 1, 32))
158 nfs_mount_data_version = 1;
159 else if (kernel_version < MAKE_VERSION(2, 2, 18))
160 nfs_mount_data_version = 3;
161 else if (kernel_version < MAKE_VERSION(2, 3, 0))
162 nfs_mount_data_version = 4;
163 else if (kernel_version < MAKE_VERSION(2, 3, 99))
164 nfs_mount_data_version = 3;
165 else if (kernel_version < MAKE_VERSION(2, 6, 3))
166 nfs_mount_data_version = 4;
168 nfs_mount_data_version = 6;
170 if (nfs_mount_data_version > NFS_MOUNT_VERSION)
171 nfs_mount_data_version = NFS_MOUNT_VERSION;
174 /* Try to build a canonical options string. */
175 static char * fix_opts_string (int flags, const char *extra_opts) {
176 const struct opt_map *om;
179 new_opts = xstrdup((flags & MS_RDONLY) ? "ro" : "rw");
180 if (flags & MS_USER) {
181 /* record who mounted this so they can unmount */
182 struct passwd *pw = getpwuid(getuid());
184 new_opts = xstrconcat3(new_opts, ",user=", pw->pw_name);
186 if (flags & MS_USERS)
187 new_opts = xstrconcat3(new_opts, ",users", "");
189 for (om = opt_map; om->opt != NULL; om++) {
192 if (om->inv || !om->mask || (flags & om->mask) != om->mask)
194 new_opts = xstrconcat3(new_opts, ",", om->opt);
197 if (extra_opts && *extra_opts) {
198 new_opts = xstrconcat3(new_opts, ",", extra_opts);
203 static int add_mtab(char *spec, char *mount_point, char *fstype,
204 int flags, char *opts, int freq, int pass)
208 int result = EX_FILEIO;
210 ment.mnt_fsname = spec;
211 ment.mnt_dir = mount_point;
212 ment.mnt_type = fstype;
213 ment.mnt_opts = fix_opts_string(flags, opts);
214 ment.mnt_freq = freq;
215 ment.mnt_passno = pass;
217 if (flags & MS_REMOUNT) {
218 update_mtab(ment.mnt_dir, &ment);
224 if ((mtab = setmntent(MOUNTED, "a+")) == NULL) {
226 nfs_error(_("Can't open mtab: %s"),
231 if (addmntent(mtab, &ment) == 1) {
232 nfs_error(_("Can't write mount entry to mtab: %s"),
237 if (fchmod(fileno(mtab), 0644) == -1) {
238 nfs_error(_("Can't set permissions on mtab: %s"),
255 printf("usage: %s remotetarget dir [-rvVwfnh] [-o nfsoptions]\n",
257 printf("options:\n");
258 printf("\t-r\t\tMount file system readonly\n");
259 printf("\t-v\t\tVerbose\n");
260 printf("\t-V\t\tPrint version\n");
261 printf("\t-w\t\tMount file system read-write\n");
262 printf("\t-f\t\tFake mount, do not actually mount\n");
263 printf("\t-n\t\tDo not update /etc/mtab\n");
264 printf("\t-s\t\tTolerate sloppy mount options rather than failing.\n");
265 printf("\t-h\t\tPrint this help\n");
266 printf("\tnfsoptions\tRefer to mount.nfs(8) or nfs(5)\n\n");
270 parse_opt(const char *opt, int *mask, char *extra_opts, int len) {
271 const struct opt_map *om;
273 for (om = opt_map; om->opt != NULL; om++) {
274 if (!strcmp (opt, om->opt)) {
283 len -= strlen(extra_opts);
285 if (*extra_opts && --len > 0)
286 strcat(extra_opts, ",");
288 if ((len -= strlen(opt)) > 0)
289 strcat(extra_opts, opt);
292 /* Take -o options list and compute 4th and 5th args to mount(2). flags
293 gets the standard options (indicated by bits) and extra_opts all the rest */
294 static void parse_opts (const char *options, int *flags, char **extra_opts)
296 if (options != NULL) {
297 char *opts = xstrdup(options);
299 int len = strlen(opts) + 1; /* include room for a null */
302 *extra_opts = xmalloc(len);
305 for (p=opts, opt=NULL; p && *p; p++) {
307 opt = p; /* begin of the option item */
309 open_quote ^= 1; /* reverse the status */
311 continue; /* still in a quoted block */
313 *p = '\0'; /* terminate the option item */
314 /* end of option item or last item */
315 if (*p == '\0' || *(p+1) == '\0') {
316 parse_opt(opt, flags, *extra_opts, len);
324 static int chk_mountpoint(char *mount_point)
328 if (stat(mount_point, &sb) < 0){
329 mount_error(NULL, mount_point, errno);
332 if (S_ISDIR(sb.st_mode) == 0){
333 mount_error(NULL, mount_point, ENOTDIR);
336 if (access(mount_point, X_OK) < 0) {
337 mount_error(NULL, mount_point, errno);
344 int main(int argc, char *argv[])
346 int c, flags = 0, mnt_err = 1, fake = 0;
347 char *spec, *mount_point, *fs_type = "nfs";
348 char *extra_opts = NULL, *mount_opts = NULL;
349 uid_t uid = getuid();
351 progname = basename(argv[0]);
353 discover_nfs_mount_data_version();
355 if(!strncmp(progname, "umount", strlen("umount"))) {
360 exit(nfsumount(argc, argv));
363 if(argv[1] && argv[1][0] == '-') {
364 if(argv[1][1] == 'V')
365 printf("%s ("PACKAGE_STRING")\n", progname);
377 mount_point = argv[2];
379 argv[2] = argv[0]; /* so that getopt error messages are correct */
380 while ((c = getopt_long(argc - 2, argv + 2, "rvVwfno:hs",
381 longopts, NULL)) != -1) {
390 printf("%s: ("PACKAGE_STRING")\n", progname);
401 case 'o': /* specify mount options */
403 mount_opts = xstrconcat3(mount_opts, ",", optarg);
405 mount_opts = xstrdup(optarg);
416 if (optind != argc-2) {
417 /* Extra non-option words at the end... */
422 if (strcmp(progname, "mount.nfs4") == 0)
426 * If a non-root user is attempting to mount, make sure the
427 * user's requested options match the options specified in
428 * /etc/fstab; otherwise, don't allow the mount.
431 struct mntentchn *mc;
433 if ((mc = getfsfile(mount_point)) == NULL ||
434 strcmp(mc->m.mnt_fsname, spec) != 0 ||
435 strcmp(mc->m.mnt_type, fs_type) != 0) {
436 fprintf(stderr, "%s: permission denied: no match for %s "
437 "found in /etc/fstab\n", progname, mount_point);
442 * 'mount' munges the options from fstab before passing them
443 * to us, so it is non-trivial to test that we have the correct
444 * set of options and we don't want to trust what the user
445 * gave us, so just take whatever is in /etc/fstab.
447 mount_opts = strdup(mc->m.mnt_opts);
450 mount_point = canonicalize(mount_point);
451 if (mount_point == NULL ||
452 mount_point[0] != '/') {
453 fprintf(stderr, "%s: unknown mount point %s\n",
454 progname, mount_point ? : "");
458 parse_opts(mount_opts, &flags, &extra_opts);
461 if (! (flags & (MS_USERS | MS_USER))) {
462 fprintf(stderr, "%s: permission denied\n", progname);
467 if (chk_mountpoint(mount_point))
470 if (strcmp(fs_type, "nfs4") == 0)
471 mnt_err = nfs4mount(spec, mount_point, flags, &extra_opts, 0, fake);
473 mnt_err = nfsmount(spec, mount_point, flags, &extra_opts, 0, fake);
479 mnt_err = add_mtab(spec, mount_point, fs_type, flags, extra_opts,
480 0, 0 /* these are always zero for NFS */ );