1 /* SPDX-License-Identifier: LGPL-2.1+ */
10 #include "alloc-util.h"
14 #include "fstab-util.h"
15 #include "generator.h"
18 #include "mount-setup.h"
19 #include "mount-util.h"
20 #include "parse-util.h"
21 #include "path-util.h"
22 #include "proc-cmdline.h"
24 #include "specifier.h"
25 #include "stat-util.h"
26 #include "string-util.h"
28 #include "unit-name.h"
31 #include "volatile-util.h"
33 typedef enum MountpointFlags
{
41 static const char *arg_dest
= "/tmp";
42 static const char *arg_dest_late
= "/tmp";
43 static bool arg_fstab_enabled
= true;
44 static char *arg_root_what
= NULL
;
45 static char *arg_root_fstype
= NULL
;
46 static char *arg_root_options
= NULL
;
47 static char *arg_root_hash
= NULL
;
48 static int arg_root_rw
= -1;
49 static char *arg_usr_what
= NULL
;
50 static char *arg_usr_fstype
= NULL
;
51 static char *arg_usr_options
= NULL
;
52 static VolatileMode arg_volatile_mode
= _VOLATILE_MODE_INVALID
;
54 static int write_options(FILE *f
, const char *options
) {
55 _cleanup_free_
char *o
= NULL
;
60 if (streq(options
, "defaults"))
63 o
= specifier_escape(options
);
67 fprintf(f
, "Options=%s\n", o
);
71 static int write_what(FILE *f
, const char *what
) {
72 _cleanup_free_
char *w
= NULL
;
74 w
= specifier_escape(what
);
78 fprintf(f
, "What=%s\n", w
);
85 MountpointFlags flags
) {
87 _cleanup_free_
char *name
= NULL
;
88 _cleanup_fclose_
FILE *f
= NULL
;
94 if (access("/proc/swaps", F_OK
) < 0) {
95 log_info("Swap not supported, ignoring fstab swap entry for %s.", what
);
99 if (detect_container() > 0) {
100 log_info("Running in a container, ignoring fstab swap entry for %s.", what
);
104 r
= unit_name_from_path(what
, ".swap", &name
);
106 return log_error_errno(r
, "Failed to generate unit name: %m");
108 r
= generator_open_unit_file(arg_dest
, "/etc/fstab", name
, &f
);
112 fputs("# Automatically generated by systemd-fstab-generator\n\n"
114 "SourcePath=/etc/fstab\n"
115 "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n\n"
118 r
= write_what(f
, what
);
122 r
= write_options(f
, me
->mnt_opts
);
126 r
= fflush_and_check(f
);
128 return log_error_errno(r
, "Failed to write unit file %s: %m", name
);
130 /* use what as where, to have a nicer error message */
131 r
= generator_write_timeouts(arg_dest
, what
, what
, me
->mnt_opts
, NULL
);
135 if (flags
& MAKEFS
) {
136 r
= generator_hook_up_mkswap(arg_dest
, what
);
142 /* TODO: swap devices must be wiped and recreated */
143 log_warning("%s: growing swap devices is currently unsupported.", what
);
145 if (!(flags
& NOAUTO
)) {
146 r
= generator_add_symlink(arg_dest
, SPECIAL_SWAP_TARGET
,
147 (flags
& NOFAIL
) ? "wants" : "requires", name
);
155 static bool mount_is_network(struct mntent
*me
) {
158 return fstab_test_option(me
->mnt_opts
, "_netdev\0") ||
159 fstype_is_network(me
->mnt_type
);
162 static bool mount_in_initrd(struct mntent
*me
) {
165 return fstab_test_option(me
->mnt_opts
, "x-initrd.mount\0") ||
166 streq(me
->mnt_dir
, "/usr");
169 static int write_timeout(FILE *f
, const char *where
, const char *opts
,
170 const char *filter
, const char *variable
) {
171 _cleanup_free_
char *timeout
= NULL
;
172 char timespan
[FORMAT_TIMESPAN_MAX
];
176 r
= fstab_filter_options(opts
, filter
, NULL
, &timeout
, NULL
);
178 return log_warning_errno(r
, "Failed to parse options: %m");
182 r
= parse_sec_fix_0(timeout
, &u
);
184 log_warning("Failed to parse timeout for %s, ignoring: %s", where
, timeout
);
188 fprintf(f
, "%s=%s\n", variable
, format_timespan(timespan
, sizeof(timespan
), u
, 0));
193 static int write_idle_timeout(FILE *f
, const char *where
, const char *opts
) {
194 return write_timeout(f
, where
, opts
,
195 "x-systemd.idle-timeout\0", "TimeoutIdleSec");
198 static int write_mount_timeout(FILE *f
, const char *where
, const char *opts
) {
199 return write_timeout(f
, where
, opts
,
200 "x-systemd.mount-timeout\0", "TimeoutSec");
203 static int write_dependency(FILE *f
, const char *opts
,
204 const char *filter
, const char *format
) {
205 _cleanup_strv_free_
char **names
= NULL
, **units
= NULL
;
206 _cleanup_free_
char *res
= NULL
;
213 r
= fstab_extract_values(opts
, filter
, &names
);
215 return log_warning_errno(r
, "Failed to parse options: %m");
219 STRV_FOREACH(s
, names
) {
222 r
= unit_name_mangle_with_suffix(*s
, 0, ".mount", &x
);
224 return log_error_errno(r
, "Failed to generate unit name: %m");
225 r
= strv_consume(&units
, x
);
231 res
= strv_join(units
, " ");
234 #pragma GCC diagnostic push
235 #pragma GCC diagnostic ignored "-Wformat-nonliteral"
236 fprintf(f
, format
, res
);
237 #pragma GCC diagnostic pop
243 static int write_after(FILE *f
, const char *opts
) {
244 return write_dependency(f
, opts
, "x-systemd.after", "After=%1$s\n");
247 static int write_requires_after(FILE *f
, const char *opts
) {
248 return write_dependency(f
, opts
,
249 "x-systemd.requires", "After=%1$s\nRequires=%1$s\n");
252 static int write_before(FILE *f
, const char *opts
) {
253 return write_dependency(f
, opts
,
254 "x-systemd.before", "Before=%1$s\n");
257 static int write_requires_mounts_for(FILE *f
, const char *opts
) {
258 _cleanup_strv_free_
char **paths
= NULL
, **paths_escaped
= NULL
;
259 _cleanup_free_
char *res
= NULL
;
265 r
= fstab_extract_values(opts
, "x-systemd.requires-mounts-for", &paths
);
267 return log_warning_errno(r
, "Failed to parse options: %m");
271 r
= specifier_escape_strv(paths
, &paths_escaped
);
273 return log_error_errno(r
, "Failed to escape paths: %m");
275 res
= strv_join(paths_escaped
, " ");
279 fprintf(f
, "RequiresMountsFor=%s\n", res
);
284 static int add_mount(
288 const char *original_where
,
292 MountpointFlags flags
,
294 const char *source
) {
298 *automount_name
= NULL
,
300 *where_escaped
= NULL
;
301 _cleanup_fclose_
FILE *f
= NULL
;
310 if (streq_ptr(fstype
, "autofs"))
313 if (!is_path(where
)) {
314 log_warning("Mount point %s is not a valid path, ignoring.", where
);
318 if (mount_point_is_api(where
) ||
319 mount_point_ignore(where
))
322 if (path_equal(where
, "/")) {
324 log_warning("Ignoring \"noauto\" for root device");
326 log_warning("Ignoring \"nofail\" for root device");
327 if (flags
& AUTOMOUNT
)
328 log_warning("Ignoring automount option for root device");
330 SET_FLAG(flags
, NOAUTO
| NOFAIL
| AUTOMOUNT
, false);
333 r
= unit_name_from_path(where
, ".mount", &name
);
335 return log_error_errno(r
, "Failed to generate unit name: %m");
337 r
= generator_open_unit_file(dest
, "/etc/fstab", name
, &f
);
344 "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
347 if (STRPTR_IN_SET(fstype
, "nfs", "nfs4") && !(flags
& AUTOMOUNT
) &&
348 fstab_test_yes_no_option(opts
, "bg\0" "fg\0")) {
349 /* The default retry timeout that mount.nfs uses for 'bg' mounts
350 * is 10000 minutes, where as it uses 2 minutes for 'fg' mounts.
351 * As we are making 'bg' mounts look like an 'fg' mount to
352 * mount.nfs (so systemd can manage the job-control aspects of 'bg'),
353 * we need to explicitly preserve that default, and also ensure
354 * the systemd mount-timeout doesn't interfere.
355 * By placing these options first, they can be over-ridden by
356 * settings in /etc/fstab. */
357 opts
= strjoina("x-systemd.mount-timeout=infinity,retry=10000,", opts
, ",fg");
358 SET_FLAG(flags
, NOFAIL
, true);
361 if (!(flags
& NOFAIL
) && !(flags
& AUTOMOUNT
))
362 fprintf(f
, "Before=%s\n", post
);
364 if (!(flags
& AUTOMOUNT
) && opts
) {
365 r
= write_after(f
, opts
);
368 r
= write_requires_after(f
, opts
);
371 r
= write_before(f
, opts
);
374 r
= write_requires_mounts_for(f
, opts
);
380 r
= generator_write_fsck_deps(f
, dest
, what
, where
, fstype
);
385 fprintf(f
, "\n[Mount]\n");
387 fprintf(f
, "# Canonicalized from %s\n", original_where
);
389 where_escaped
= specifier_escape(where
);
392 fprintf(f
, "Where=%s\n", where_escaped
);
394 r
= write_what(f
, what
);
398 if (!isempty(fstype
) && !streq(fstype
, "auto")) {
399 _cleanup_free_
char *t
;
401 t
= specifier_escape(fstype
);
405 fprintf(f
, "Type=%s\n", t
);
408 r
= generator_write_timeouts(dest
, what
, where
, opts
, &filtered
);
412 r
= generator_write_device_deps(dest
, what
, where
, opts
);
416 r
= write_mount_timeout(f
, where
, opts
);
420 r
= write_options(f
, filtered
);
424 r
= fflush_and_check(f
);
426 return log_error_errno(r
, "Failed to write unit file %s: %m", name
);
428 if (flags
& MAKEFS
) {
429 r
= generator_hook_up_mkfs(dest
, what
, where
, fstype
);
434 if (flags
& GROWFS
) {
435 r
= generator_hook_up_growfs(dest
, where
, post
);
440 if (!(flags
& NOAUTO
) && !(flags
& AUTOMOUNT
)) {
441 r
= generator_add_symlink(dest
, post
,
442 (flags
& NOFAIL
) ? "wants" : "requires", name
);
447 if (flags
& AUTOMOUNT
) {
448 r
= unit_name_from_path(where
, ".automount", &automount_name
);
450 return log_error_errno(r
, "Failed to generate unit name: %m");
454 r
= generator_open_unit_file(dest
, "/etc/fstab", automount_name
, &f
);
461 "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
464 fprintf(f
, "Before=%s\n", post
);
467 r
= write_after(f
, opts
);
470 r
= write_requires_after(f
, opts
);
473 r
= write_before(f
, opts
);
476 r
= write_requires_mounts_for(f
, opts
);
487 r
= write_idle_timeout(f
, where
, opts
);
491 r
= fflush_and_check(f
);
493 return log_error_errno(r
, "Failed to write unit file %s: %m", automount_name
);
495 r
= generator_add_symlink(dest
, post
,
496 (flags
& NOFAIL
) ? "wants" : "requires", automount_name
);
504 static int parse_fstab(bool initrd
) {
505 _cleanup_endmntent_
FILE *f
= NULL
;
506 const char *fstab_path
;
510 fstab_path
= initrd
? "/sysroot/etc/fstab" : "/etc/fstab";
511 f
= setmntent(fstab_path
, "re");
516 return log_error_errno(errno
, "Failed to open %s: %m", fstab_path
);
519 while ((me
= getmntent(f
))) {
520 _cleanup_free_
char *where
= NULL
, *what
= NULL
, *canonical_where
= NULL
;
521 bool makefs
, growfs
, noauto
, nofail
;
524 if (initrd
&& !mount_in_initrd(me
))
527 what
= fstab_node_to_udev_node(me
->mnt_fsname
);
531 if (is_device_path(what
) && path_is_read_only_fs("sys") > 0) {
532 log_info("Running in a container, ignoring fstab device entry for %s.", what
);
536 where
= strdup(me
->mnt_dir
);
540 if (is_path(where
)) {
541 path_simplify(where
, false);
543 /* Follow symlinks here; see 5261ba901845c084de5a8fd06500ed09bfb0bd80 which makes sense for
544 * mount units, but causes problems since it historically worked to have symlinks in e.g.
545 * /etc/fstab. So we canonicalize here. Note that we use CHASE_NONEXISTENT to handle the case
546 * where a symlink refers to another mount target; this works assuming the sub-mountpoint
547 * target is the final directory. */
548 r
= chase_symlinks(where
, initrd
? "/sysroot" : NULL
,
549 CHASE_PREFIX_ROOT
| CHASE_NONEXISTENT
,
551 if (r
< 0) /* If we can't canonicalize we continue on as if it wasn't a symlink */
552 log_debug_errno(r
, "Failed to read symlink target for %s, ignoring: %m", where
);
553 else if (streq(canonical_where
, where
)) /* If it was fully canonicalized, suppress the change */
554 canonical_where
= mfree(canonical_where
);
556 log_debug("Canonicalized what=%s where=%s to %s", what
, where
, canonical_where
);
559 makefs
= fstab_test_option(me
->mnt_opts
, "x-systemd.makefs\0");
560 growfs
= fstab_test_option(me
->mnt_opts
, "x-systemd.growfs\0");
561 noauto
= fstab_test_yes_no_option(me
->mnt_opts
, "noauto\0" "auto\0");
562 nofail
= fstab_test_yes_no_option(me
->mnt_opts
, "nofail\0" "fail\0");
564 log_debug("Found entry what=%s where=%s type=%s makefs=%s nofail=%s noauto=%s",
565 what
, where
, me
->mnt_type
,
567 yes_no(noauto
), yes_no(nofail
));
569 if (streq(me
->mnt_type
, "swap"))
570 k
= add_swap(what
, me
,
571 makefs
*MAKEFS
| growfs
*GROWFS
| noauto
*NOAUTO
| nofail
*NOFAIL
);
576 automount
= fstab_test_option(me
->mnt_opts
,
577 "comment=systemd.automount\0"
578 "x-systemd.automount\0");
580 post
= SPECIAL_INITRD_FS_TARGET
;
581 else if (mount_is_network(me
))
582 post
= SPECIAL_REMOTE_FS_TARGET
;
584 post
= SPECIAL_LOCAL_FS_TARGET
;
586 k
= add_mount(arg_dest
,
588 canonical_where
?: where
,
589 canonical_where
? where
: NULL
,
593 makefs
*MAKEFS
| growfs
*GROWFS
| noauto
*NOAUTO
| nofail
*NOFAIL
| automount
*AUTOMOUNT
,
605 static int add_sysroot_mount(void) {
606 _cleanup_free_
char *what
= NULL
;
610 if (isempty(arg_root_what
)) {
611 log_debug("Could not find a root= entry on the kernel command line.");
615 if (streq(arg_root_what
, "gpt-auto")) {
616 /* This is handled by the gpt-auto generator */
617 log_debug("Skipping root directory handling, as gpt-auto was requested.");
621 if (path_equal(arg_root_what
, "/dev/nfs")) {
622 /* This is handled by the kernel or the initrd */
623 log_debug("Skipping root directory handling, as /dev/nfs was requested.");
627 what
= fstab_node_to_udev_node(arg_root_what
);
631 if (!arg_root_options
)
632 opts
= arg_root_rw
> 0 ? "rw" : "ro";
633 else if (arg_root_rw
>= 0 ||
634 !fstab_test_option(arg_root_options
, "ro\0" "rw\0"))
635 opts
= strjoina(arg_root_options
, ",", arg_root_rw
> 0 ? "rw" : "ro");
637 opts
= arg_root_options
;
639 log_debug("Found entry what=%s where=/sysroot type=%s", what
, strna(arg_root_fstype
));
641 if (is_device_path(what
)) {
642 r
= generator_write_initrd_root_device_deps(arg_dest
, what
);
647 return add_mount(arg_dest
,
653 is_device_path(what
) ? 1 : 0, /* passno */
654 0, /* makefs off, growfs off, noauto off, nofail off, automount off */
655 SPECIAL_INITRD_ROOT_FS_TARGET
,
659 static int add_sysroot_usr_mount(void) {
660 _cleanup_free_
char *what
= NULL
;
663 if (!arg_usr_what
&& !arg_usr_fstype
&& !arg_usr_options
)
666 if (arg_root_what
&& !arg_usr_what
) {
667 /* Copy over the root device, in case the /usr mount just differs in a mount option (consider btrfs subvolumes) */
668 arg_usr_what
= strdup(arg_root_what
);
673 if (arg_root_fstype
&& !arg_usr_fstype
) {
674 arg_usr_fstype
= strdup(arg_root_fstype
);
679 if (arg_root_options
&& !arg_usr_options
) {
680 arg_usr_options
= strdup(arg_root_options
);
681 if (!arg_usr_options
)
688 what
= fstab_node_to_udev_node(arg_usr_what
);
692 if (!arg_usr_options
)
693 opts
= arg_root_rw
> 0 ? "rw" : "ro";
694 else if (!fstab_test_option(arg_usr_options
, "ro\0" "rw\0"))
695 opts
= strjoina(arg_usr_options
, ",", arg_root_rw
> 0 ? "rw" : "ro");
697 opts
= arg_usr_options
;
699 log_debug("Found entry what=%s where=/sysroot/usr type=%s", what
, strna(arg_usr_fstype
));
700 return add_mount(arg_dest
,
706 is_device_path(what
) ? 1 : 0, /* passno */
708 SPECIAL_INITRD_FS_TARGET
,
712 static int add_volatile_root(void) {
713 const char *from
, *to
;
715 if (arg_volatile_mode
!= VOLATILE_YES
)
718 /* Let's add in systemd-remount-volatile.service which will remount the root device to tmpfs if this is
719 * requested, leaving only /usr from the root mount inside. */
721 from
= strjoina(SYSTEM_DATA_UNIT_PATH
"/systemd-volatile-root.service");
722 to
= strjoina(arg_dest
, "/" SPECIAL_INITRD_ROOT_FS_TARGET
, ".requires/systemd-volatile-root.service");
724 (void) mkdir_parents(to
, 0755);
726 if (symlink(from
, to
) < 0)
727 return log_error_errno(errno
, "Failed to hook in volatile remount service: %m");
732 static int add_volatile_var(void) {
734 if (arg_volatile_mode
!= VOLATILE_STATE
)
737 /* If requested, mount /var as tmpfs, but do so only if there's nothing else defined for this. */
739 return add_mount(arg_dest_late
,
747 SPECIAL_LOCAL_FS_TARGET
,
751 static int parse_proc_cmdline_item(const char *key
, const char *value
, void *data
) {
754 /* root=, usr=, usrfstype= and roofstype= may occur more than once, the last
755 * instance should take precedence. In the case of multiple rootflags=
756 * or usrflags= the arguments should be concatenated */
758 if (STR_IN_SET(key
, "fstab", "rd.fstab")) {
760 r
= value
? parse_boolean(value
) : 1;
762 log_warning("Failed to parse fstab switch %s. Ignoring.", value
);
764 arg_fstab_enabled
= r
;
766 } else if (streq(key
, "root")) {
768 if (proc_cmdline_value_missing(key
, value
))
771 if (free_and_strdup(&arg_root_what
, value
) < 0)
774 } else if (streq(key
, "rootfstype")) {
776 if (proc_cmdline_value_missing(key
, value
))
779 if (free_and_strdup(&arg_root_fstype
, value
) < 0)
782 } else if (streq(key
, "rootflags")) {
784 if (proc_cmdline_value_missing(key
, value
))
787 if (!strextend_with_separator(&arg_root_options
, ",", value
, NULL
))
790 } else if (streq(key
, "roothash")) {
792 if (proc_cmdline_value_missing(key
, value
))
795 if (free_and_strdup(&arg_root_hash
, value
) < 0)
798 } else if (streq(key
, "mount.usr")) {
800 if (proc_cmdline_value_missing(key
, value
))
803 if (free_and_strdup(&arg_usr_what
, value
) < 0)
806 } else if (streq(key
, "mount.usrfstype")) {
808 if (proc_cmdline_value_missing(key
, value
))
811 if (free_and_strdup(&arg_usr_fstype
, value
) < 0)
814 } else if (streq(key
, "mount.usrflags")) {
816 if (proc_cmdline_value_missing(key
, value
))
819 if (!strextend_with_separator(&arg_usr_options
, ",", value
, NULL
))
822 } else if (streq(key
, "rw") && !value
)
824 else if (streq(key
, "ro") && !value
)
826 else if (streq(key
, "systemd.volatile")) {
830 m
= volatile_mode_from_string(value
);
832 log_warning("Failed to parse systemd.volatile= argument: %s", value
);
834 arg_volatile_mode
= m
;
836 arg_volatile_mode
= VOLATILE_YES
;
842 static int determine_root(void) {
843 /* If we have a root hash but no root device then Verity is used, and we use the "root" DM device as root. */
851 arg_root_what
= strdup("/dev/mapper/root");
855 log_info("Using verity root device %s.", arg_root_what
);
860 int main(int argc
, char *argv
[]) {
863 if (argc
> 1 && argc
!= 4) {
864 log_error("This program takes three or no arguments.");
871 arg_dest_late
= argv
[3];
873 log_set_prohibit_ipc(true);
874 log_set_target(LOG_TARGET_AUTO
);
875 log_parse_environment();
880 r
= proc_cmdline_parse(parse_proc_cmdline_item
, NULL
, 0);
882 log_warning_errno(r
, "Failed to parse kernel command line, ignoring: %m");
884 (void) determine_root();
886 /* Always honour root= and usr= in the kernel command line if we are in an initrd */
890 r
= add_sysroot_mount();
892 k
= add_sysroot_usr_mount();
896 k
= add_volatile_root();
900 r
= add_volatile_var();
902 /* Honour /etc/fstab only when that's enabled */
903 if (arg_fstab_enabled
) {
906 log_debug("Parsing /etc/fstab");
908 /* Parse the local /etc/fstab, possibly from the initrd */
909 k
= parse_fstab(false);
913 /* If running in the initrd also parse the /etc/fstab from the host */
915 log_debug("Parsing /sysroot/etc/fstab");
917 k
= parse_fstab(true);
924 free(arg_root_fstype
);
925 free(arg_root_options
);
929 free(arg_usr_fstype
);
930 free(arg_usr_options
);
932 return r
< 0 ? EXIT_FAILURE
: EXIT_SUCCESS
;