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"
48 int nfs_mount_data_version;
54 #define FOREGROUND (0)
55 #define BACKGROUND (1)
57 static struct option longopts[] = {
58 { "fake", 0, 0, 'f' },
59 { "help", 0, 0, 'h' },
60 { "no-mtab", 0, 0, 'n' },
61 { "read-only", 0, 0, 'r' },
63 { "verbose", 0, 0, 'v' },
64 { "version", 0, 0, 'V' },
65 { "read-write", 0, 0, 'w' },
67 { "string", 0, 0, 'i' },
68 { "options", 1, 0, 'o' },
73 * Map from -o and fstab option strings to the flag argument to mount(2).
76 const char *opt; /* option name */
77 int skip; /* skip in mtab option string */
78 int inv; /* true if flag value should be inverted */
79 int mask; /* flag mask value */
82 static const struct opt_map opt_map[] = {
83 { "defaults", 0, 0, 0 }, /* default options */
84 { "ro", 1, 0, MS_RDONLY }, /* read-only */
85 { "rw", 1, 1, MS_RDONLY }, /* read-write */
86 { "exec", 0, 1, MS_NOEXEC }, /* permit execution of binaries */
87 { "noexec", 0, 0, MS_NOEXEC }, /* don't execute binaries */
88 { "suid", 0, 1, MS_NOSUID }, /* honor suid executables */
89 { "nosuid", 0, 0, MS_NOSUID }, /* don't honor suid executables */
90 { "dev", 0, 1, MS_NODEV }, /* interpret device files */
91 { "nodev", 0, 0, MS_NODEV }, /* don't interpret devices */
92 { "sync", 0, 0, MS_SYNCHRONOUS}, /* synchronous I/O */
93 { "async", 0, 1, MS_SYNCHRONOUS}, /* asynchronous I/O */
94 { "dirsync", 0, 0, MS_DIRSYNC}, /* synchronous directory modifications */
95 { "remount", 0, 0, MS_REMOUNT}, /* Alter flags of mounted FS */
96 { "bind", 0, 0, MS_BIND }, /* Remount part of tree elsewhere */
97 { "rbind", 0, 0, MS_BIND|MS_REC }, /* Idem, plus mounted subtrees */
98 { "auto", 0, 0, MS_DUMMY }, /* Can be mounted using -a */
99 { "noauto", 0, 0, MS_DUMMY }, /* Can only be mounted explicitly */
100 { "users", 1, 0, MS_USERS }, /* Allow ordinary user to mount */
101 { "nousers", 0, 1, MS_DUMMY }, /* Forbid ordinary user to mount */
102 { "user", 1, 0, MS_USER }, /* Allow ordinary user to mount */
103 { "nouser", 0, 1, MS_DUMMY }, /* Forbid ordinary user to mount */
104 { "owner", 0, 0, MS_DUMMY }, /* Let the owner of the device mount */
105 { "noowner", 0, 0, MS_DUMMY }, /* Device owner has no special privs */
106 { "group", 0, 0, MS_DUMMY }, /* Let the group of the device mount */
107 { "nogroup", 0, 0, MS_DUMMY }, /* Device group has no special privs */
108 { "_netdev", 0, 0, MS_DUMMY}, /* Device requires network */
109 { "comment", 0, 0, MS_DUMMY}, /* fstab comment only (kudzu,_netdev)*/
111 /* add new options here */
113 { "sub", 0, 1, MS_NOSUB }, /* allow submounts */
114 { "nosub", 0, 0, MS_NOSUB }, /* don't allow submounts */
117 { "quiet", 0, 0, MS_SILENT }, /* be quiet */
118 { "loud", 0, 1, MS_SILENT }, /* print out messages. */
121 { "mand", 0, 0, MS_MANDLOCK }, /* Allow mandatory locks on this FS */
122 { "nomand", 0, 1, MS_MANDLOCK }, /* Forbid mandatory locks on this FS */
124 { "loop", 1, 0, MS_DUMMY }, /* use a loop device */
126 { "atime", 0, 1, MS_NOATIME }, /* Update access time */
127 { "noatime", 0, 0, MS_NOATIME }, /* Do not update access time */
130 { "diratime", 0, 1, MS_NODIRATIME }, /* Update dir access times */
131 { "nodiratime", 0, 0, MS_NODIRATIME },/* Do not update dir access times */
136 #define MAKE_VERSION(p,q,r) (65536 * (p) + 256 * (q) + (r))
138 int linux_version_code(void)
140 struct utsname my_utsname;
143 if (uname(&my_utsname) == 0) {
144 p = atoi(strtok(my_utsname.release, "."));
145 q = atoi(strtok(NULL, "."));
146 r = atoi(strtok(NULL, "."));
147 return MAKE_VERSION(p,q,r);
153 * Choose the version of the nfs_mount_data structure that is appropriate
154 * for the kernel that is doing the mount.
156 * NFS_MOUNT_VERSION: maximum version supported by these sources
157 * nfs_mount_data_version: maximum version supported by the running kernel
159 static void discover_nfs_mount_data_version(void)
161 int kernel_version = linux_version_code();
163 if (kernel_version) {
164 if (kernel_version < MAKE_VERSION(2, 1, 32))
165 nfs_mount_data_version = 1;
166 else if (kernel_version < MAKE_VERSION(2, 2, 18))
167 nfs_mount_data_version = 3;
168 else if (kernel_version < MAKE_VERSION(2, 3, 0))
169 nfs_mount_data_version = 4;
170 else if (kernel_version < MAKE_VERSION(2, 3, 99))
171 nfs_mount_data_version = 3;
172 else if (kernel_version < MAKE_VERSION(2, 6, 3))
173 nfs_mount_data_version = 4;
175 nfs_mount_data_version = 6;
177 if (nfs_mount_data_version > NFS_MOUNT_VERSION)
178 nfs_mount_data_version = NFS_MOUNT_VERSION;
181 static void print_one(char *spec, char *node, char *type, char *opts)
187 printf(_("%s on %s type %s (%s)\n"), spec, node, type, opts);
189 printf(_("%s on %s type %s\n"), spec, node, type);
193 * Build a canonical mount option string for /etc/mtab.
195 static char *fix_opts_string(int flags, const char *extra_opts)
197 const struct opt_map *om;
200 new_opts = xstrdup((flags & MS_RDONLY) ? "ro" : "rw");
201 if (flags & MS_USER) {
202 /* record who mounted this so they can unmount */
203 struct passwd *pw = getpwuid(getuid());
205 new_opts = xstrconcat3(new_opts, ",user=", pw->pw_name);
207 if (flags & MS_USERS)
208 new_opts = xstrconcat3(new_opts, ",users", "");
210 for (om = opt_map; om->opt != NULL; om++) {
213 if (om->inv || !om->mask || (flags & om->mask) != om->mask)
215 new_opts = xstrconcat3(new_opts, ",", om->opt);
218 if (extra_opts && *extra_opts) {
219 new_opts = xstrconcat3(new_opts, ",", extra_opts);
224 static int add_mtab(char *spec, char *mount_point, char *fstype,
225 int flags, char *opts, int freq, int pass)
229 int result = EX_FILEIO;
231 ment.mnt_fsname = spec;
232 ment.mnt_dir = mount_point;
233 ment.mnt_type = fstype;
234 ment.mnt_opts = fix_opts_string(flags, opts);
235 ment.mnt_freq = freq;
236 ment.mnt_passno = pass;
238 if (flags & MS_REMOUNT) {
239 update_mtab(ment.mnt_dir, &ment);
246 if ((mtab = setmntent(MOUNTED, "a+")) == NULL) {
248 nfs_error(_("Can't open mtab: %s"),
253 if (addmntent(mtab, &ment) == 1) {
254 nfs_error(_("Can't write mount entry to mtab: %s"),
259 if (fchmod(fileno(mtab), 0644) == -1) {
260 nfs_error(_("Can't set permissions on mtab: %s"),
276 void mount_usage(void)
278 printf(_("usage: %s remotetarget dir [-rvVwfnsih] [-o nfsoptions]\n"),
280 printf(_("options:\n"));
281 printf(_("\t-r\t\tMount file system readonly\n"));
282 printf(_("\t-v\t\tVerbose\n"));
283 printf(_("\t-V\t\tPrint version\n"));
284 printf(_("\t-w\t\tMount file system read-write\n"));
285 printf(_("\t-f\t\tFake mount, do not actually mount\n"));
286 printf(_("\t-n\t\tDo not update /etc/mtab\n"));
287 printf(_("\t-s\t\tTolerate sloppy mount options rather than fail\n"));
288 printf(_("\t-i\t\tPass mount options to the kernel via a string\n"));
289 printf(_("\t-h\t\tPrint this help\n"));
290 printf(_("\tnfsoptions\tRefer to mount.nfs(8) or nfs(5)\n\n"));
293 static void parse_opt(const char *opt, int *mask, char *extra_opts, int len)
295 const struct opt_map *om;
297 for (om = opt_map; om->opt != NULL; om++) {
298 if (!strcmp (opt, om->opt)) {
307 len -= strlen(extra_opts);
309 if (*extra_opts && --len > 0)
310 strcat(extra_opts, ",");
312 if ((len -= strlen(opt)) > 0)
313 strcat(extra_opts, opt);
317 * Convert the provided mount command-line options into the 4th &
318 * 5th arguments to mount(2). Output parameter "@flags" gets the
319 * standard options (indicated by MS_ bits), and output parameter
320 * "@extra_opts" gets all the filesystem-specific options.
322 static void parse_opts(const char *options, int *flags, char **extra_opts)
324 if (options != NULL) {
325 char *opts = xstrdup(options);
327 int len = strlen(opts) + 1; /* include room for a null */
330 *extra_opts = xmalloc(len);
333 for (p = opts, opt = NULL; p && *p; p++) {
335 opt = p; /* begin of the option item */
337 open_quote ^= 1; /* reverse the status */
339 continue; /* still in a quoted block */
341 *p = '\0'; /* terminate the option item */
343 /* end of option item or last item */
344 if (*p == '\0' || *(p + 1) == '\0') {
345 parse_opt(opt, flags, *extra_opts, len);
353 static int chk_mountpoint(char *mount_point)
357 if (stat(mount_point, &sb) < 0){
358 mount_error(NULL, mount_point, errno);
361 if (S_ISDIR(sb.st_mode) == 0){
362 mount_error(NULL, mount_point, ENOTDIR);
365 if (access(mount_point, X_OK) < 0) {
366 mount_error(NULL, mount_point, errno);
373 static int try_mount(char *spec, char *mount_point, int flags,
374 char *fs_type, char **extra_opts, char *mount_opts,
375 int fake, int nomtab, int bg)
380 ret = nfsmount_string(spec, mount_point, fs_type, flags,
381 extra_opts, fake, bg);
383 if (strcmp(fs_type, "nfs4") == 0)
384 ret = nfs4mount(spec, mount_point, flags,
385 extra_opts, fake, bg);
387 ret = nfsmount(spec, mount_point, flags,
388 extra_opts, fake, bg);
395 print_one(spec, mount_point, fs_type, mount_opts);
398 ret = add_mtab(spec, mount_point, fs_type, flags, *extra_opts,
399 0, 0 /* these are always zero for NFS */ );
403 int main(int argc, char *argv[])
405 int c, flags = 0, mnt_err = 1, fake = 0;
406 char *spec, *mount_point, *fs_type = "nfs";
407 char *extra_opts = NULL, *mount_opts = NULL;
408 uid_t uid = getuid();
410 progname = basename(argv[0]);
412 discover_nfs_mount_data_version();
414 if(!strncmp(progname, "umount", strlen("umount")))
415 exit(nfsumount(argc, argv));
417 if (argv[1] && argv[1][0] == '-') {
418 if(argv[1][1] == 'V')
419 printf("%s ("PACKAGE_STRING")\n", progname);
431 mount_point = argv[2];
433 argv[2] = argv[0]; /* so that getopt error messages are correct */
434 while ((c = getopt_long(argc - 2, argv + 2, "rvVwfno:hsi",
435 longopts, NULL)) != -1) {
444 printf("%s: ("PACKAGE_STRING")\n", progname);
455 case 'o': /* specify mount options */
457 mount_opts = xstrconcat3(mount_opts, ",", optarg);
459 mount_opts = xstrdup(optarg);
465 if (linux_version_code() < MAKE_VERSION(2, 6, 23)) {
466 nfs_error(_("%s: Passing mount options via a"
467 " string is unsupported by this"
468 " kernel\n"), progname);
472 nfs_error(_("%s: -i option is restricted to 'root'\n"),
486 * Extra non-option words at the end are bogus...
488 if (optind != argc - 2) {
493 if (strcmp(progname, "mount.nfs4") == 0)
497 * If a non-root user is attempting to mount, make sure the
498 * user's requested options match the options specified in
499 * /etc/fstab; otherwise, don't allow the mount.
502 struct mntentchn *mc;
504 if ((mc = getfsfile(mount_point)) == NULL ||
505 strcmp(mc->m.mnt_fsname, spec) != 0 ||
506 strcmp(mc->m.mnt_type, fs_type) != 0) {
507 nfs_error(_("%s: permission denied: no match for %s "
508 "found in /etc/fstab"), progname, mount_point);
513 * 'mount' munges the options from fstab before passing them
514 * to us, so it is non-trivial to test that we have the correct
515 * set of options and we don't want to trust what the user
516 * gave us, so just take whatever is in /etc/fstab.
518 mount_opts = strdup(mc->m.mnt_opts);
521 mount_point = canonicalize(mount_point);
523 nfs_error(_("%s: no mount point provided"), progname);
526 if (mount_point[0] != '/') {
527 nfs_error(_("%s: unrecognized mount point %s"),
528 progname, mount_point);
533 parse_opts(mount_opts, &flags, &extra_opts);
536 if (!(flags & (MS_USERS|MS_USER))) {
537 nfs_error(_("%s: permission denied"), progname);
543 if (chk_mountpoint(mount_point)) {
548 mnt_err = try_mount(spec, mount_point, flags, fs_type, &extra_opts,
549 mount_opts, fake, nomtab, FOREGROUND);
550 if (mnt_err == EX_BG) {
551 printf(_("%s: backgrounding \"%s\"\n"),
556 * Parent exits immediately with success.
559 nfs_error(_("%s: failed to start "
560 "background process: %s\n"),
561 progname, strerror(errno));
565 mnt_err = try_mount(spec, mount_point, flags, fs_type,
566 &extra_opts, mount_opts, fake,
568 if (verbose && mnt_err)
569 printf(_("%s: giving up \"%s\"\n"),