fstab-generator.c revision 3f85ef0f05ffc51e19f86fb83a1c51e8e3cd6817
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering/***
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering This file is part of systemd.
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering Copyright 2012 Lennart Poettering
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering systemd is free software; you can redistribute it and/or modify it
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering under the terms of the GNU Lesser General Public License as published by
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering the Free Software Foundation; either version 2.1 of the License, or
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering (at your option) any later version.
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering systemd is distributed in the hope that it will be useful, but
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering WITHOUT ANY WARRANTY; without even the implied warranty of
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
d360705f0f1262d49cccb6507abeafb7cfb5bbe0Lennart Poettering Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdio.h>
#include <mntent.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include "log.h"
#include "util.h"
#include "unit-name.h"
#include "path-util.h"
#include "mount-setup.h"
#include "special.h"
#include "mkdir.h"
#include "fileio.h"
#include "generator.h"
#include "strv.h"
#include "virt.h"
static const char *arg_dest = "/tmp";
static bool arg_fstab_enabled = true;
static char *arg_root_what = NULL;
static char *arg_root_fstype = NULL;
static char *arg_root_options = NULL;
static int arg_root_rw = -1;
static char *arg_usr_what = NULL;
static char *arg_usr_fstype = NULL;
static char *arg_usr_options = NULL;
static int mount_find_pri(struct mntent *me, int *ret) {
char *end, *opt;
unsigned long r;
assert(me);
assert(ret);
opt = hasmntopt(me, "pri");
if (!opt)
return 0;
opt += strlen("pri");
if (*opt != '=')
return -EINVAL;
errno = 0;
r = strtoul(opt + 1, &end, 10);
if (errno > 0)
return -errno;
if (end == opt + 1 || (*end != ',' && *end != 0))
return -EINVAL;
*ret = (int) r;
return 1;
}
static int add_swap(const char *what, struct mntent *me) {
_cleanup_free_ char *name = NULL, *unit = NULL, *lnk = NULL;
_cleanup_fclose_ FILE *f = NULL;
bool noauto;
int r, pri = -1;
assert(what);
assert(me);
if (detect_container(NULL) > 0) {
log_info("Running in a container, ignoring fstab swap entry for %s.", what);
return 0;
}
r = mount_find_pri(me, &pri);
if (r < 0) {
log_error("Failed to parse priority");
return r;
}
noauto = !!hasmntopt(me, "noauto");
name = unit_name_from_path(what, ".swap");
if (!name)
return log_oom();
unit = strjoin(arg_dest, "/", name, NULL);
if (!unit)
return log_oom();
f = fopen(unit, "wxe");
if (!f) {
if (errno == EEXIST)
log_error("Failed to create swap unit file %s, as it already exists. Duplicate entry in /etc/fstab?", unit);
else
log_error("Failed to create unit file %s: %m", unit);
return -errno;
}
fprintf(f,
"# Automatically generated by systemd-fstab-generator\n\n"
"[Unit]\n"
"SourcePath=/etc/fstab\n"
"Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n\n"
"[Swap]\n"
"What=%s\n",
what);
/* Note that we currently pass the priority field twice, once
* in Priority=, and once in Options= */
if (pri >= 0)
fprintf(f, "Priority=%i\n", pri);
if (!isempty(me->mnt_opts) && !streq(me->mnt_opts, "defaults"))
fprintf(f, "Options=%s\n", me->mnt_opts);
r = fflush_and_check(f);
if (r < 0) {
log_error("Failed to write unit file %s: %s", unit, strerror(-r));
return r;
}
/* use what as where, to have a nicer error message */
r = generator_write_timeouts(arg_dest, what, what, me->mnt_opts, NULL);
if (r < 0)
return r;
if (!noauto) {
lnk = strjoin(arg_dest, "/" SPECIAL_SWAP_TARGET ".wants/", name, NULL);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(unit, lnk) < 0) {
log_error("Failed to create symlink %s: %m", lnk);
return -errno;
}
}
return 0;
}
static bool mount_is_network(struct mntent *me) {
assert(me);
return
hasmntopt(me, "_netdev") ||
fstype_is_network(me->mnt_type);
}
static bool mount_in_initrd(struct mntent *me) {
assert(me);
return
hasmntopt(me, "x-initrd.mount") ||
streq(me->mnt_dir, "/usr");
}
static int add_mount(
const char *what,
const char *where,
const char *fstype,
const char *opts,
int passno,
bool noauto,
bool nofail,
bool automount,
const char *post,
const char *source) {
_cleanup_free_ char
*name = NULL, *unit = NULL, *lnk = NULL,
*automount_name = NULL, *automount_unit = NULL,
*filtered = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(what);
assert(where);
assert(opts);
assert(source);
if (streq_ptr(fstype, "autofs"))
return 0;
if (!is_path(where)) {
log_warning("Mount point %s is not a valid path, ignoring.", where);
return 0;
}
if (mount_point_is_api(where) ||
mount_point_ignore(where))
return 0;
if (path_equal(where, "/")) {
/* The root disk is not an option */
automount = false;
noauto = false;
nofail = false;
}
name = unit_name_from_path(where, ".mount");
if (!name)
return log_oom();
unit = strjoin(arg_dest, "/", name, NULL);
if (!unit)
return log_oom();
f = fopen(unit, "wxe");
if (!f) {
if (errno == EEXIST)
log_error("Failed to create mount unit file %s, as it already exists. Duplicate entry in /etc/fstab?", unit);
else
log_error("Failed to create unit file %s: %m", unit);
return -errno;
}
fprintf(f,
"# Automatically generated by systemd-fstab-generator\n\n"
"[Unit]\n"
"SourcePath=%s\n"
"Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
source);
if (post && !noauto && !nofail && !automount)
fprintf(f, "Before=%s\n", post);
if (passno != 0) {
r = generator_write_fsck_deps(f, arg_dest, what, where, fstype);
if (r < 0)
return r;
}
fprintf(f,
"\n"
"[Mount]\n"
"What=%s\n"
"Where=%s\n",
what,
where);
if (!isempty(fstype) && !streq(fstype, "auto"))
fprintf(f, "Type=%s\n", fstype);
r = generator_write_timeouts(arg_dest, what, where, opts, &filtered);
if (r < 0)
return r;
if (!isempty(filtered) && !streq(filtered, "defaults"))
fprintf(f, "Options=%s\n", filtered);
fflush(f);
if (ferror(f)) {
log_error("Failed to write unit file %s: %m", unit);
return -errno;
}
if (!noauto && post) {
lnk = strjoin(arg_dest, "/", post, nofail || automount ? ".wants/" : ".requires/", name, NULL);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(unit, lnk) < 0) {
log_error("Failed to create symlink %s: %m", lnk);
return -errno;
}
}
if (automount) {
automount_name = unit_name_from_path(where, ".automount");
if (!automount_name)
return log_oom();
automount_unit = strjoin(arg_dest, "/", automount_name, NULL);
if (!automount_unit)
return log_oom();
fclose(f);
f = fopen(automount_unit, "wxe");
if (!f) {
log_error("Failed to create unit file %s: %m", automount_unit);
return -errno;
}
fprintf(f,
"# Automatically generated by systemd-fstab-generator\n\n"
"[Unit]\n"
"SourcePath=%s\n"
"Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
source);
if (post)
fprintf(f,
"Before=%s\n",
post);
fprintf(f,
"[Automount]\n"
"Where=%s\n",
where);
fflush(f);
if (ferror(f)) {
log_error("Failed to write unit file %s: %m", automount_unit);
return -errno;
}
free(lnk);
lnk = strjoin(arg_dest, "/", post, nofail ? ".wants/" : ".requires/", automount_name, NULL);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(automount_unit, lnk) < 0) {
log_error("Failed to create symlink %s: %m", lnk);
return -errno;
}
}
return 0;
}
static int parse_fstab(bool initrd) {
_cleanup_endmntent_ FILE *f = NULL;
const char *fstab_path;
struct mntent *me;
int r = 0;
fstab_path = initrd ? "/sysroot/etc/fstab" : "/etc/fstab";
f = setmntent(fstab_path, "re");
if (!f) {
if (errno == ENOENT)
return 0;
log_error("Failed to open %s: %m", fstab_path);
return -errno;
}
while ((me = getmntent(f))) {
_cleanup_free_ char *where = NULL, *what = NULL;
int k;
if (initrd && !mount_in_initrd(me))
continue;
what = fstab_node_to_udev_node(me->mnt_fsname);
if (!what)
return log_oom();
if (detect_container(NULL) > 0 && is_device_path(what)) {
log_info("Running in a container, ignoring fstab device entry for %s.", what);
continue;
}
where = initrd ? strappend("/sysroot/", me->mnt_dir) : strdup(me->mnt_dir);
if (!where)
return log_oom();
if (is_path(where))
path_kill_slashes(where);
log_debug("Found entry what=%s where=%s type=%s", what, where, me->mnt_type);
if (streq(me->mnt_type, "swap"))
k = add_swap(what, me);
else {
bool noauto, nofail, automount;
const char *post;
noauto = !!hasmntopt(me, "noauto");
nofail = !!hasmntopt(me, "nofail");
automount =
hasmntopt(me, "comment=systemd.automount") ||
hasmntopt(me, "x-systemd.automount");
if (initrd)
post = SPECIAL_INITRD_FS_TARGET;
else if (mount_in_initrd(me))
post = SPECIAL_INITRD_ROOT_FS_TARGET;
else if (mount_is_network(me))
post = SPECIAL_REMOTE_FS_TARGET;
else
post = SPECIAL_LOCAL_FS_TARGET;
k = add_mount(what,
where,
me->mnt_type,
me->mnt_opts,
me->mnt_passno,
noauto,
nofail,
automount,
post,
fstab_path);
}
if (k < 0)
r = k;
}
return r;
}
static int add_root_mount(void) {
_cleanup_free_ char *what = NULL;
const char *opts;
if (isempty(arg_root_what)) {
log_debug("Could not find a root= entry on the kernel command line.");
return 0;
}
what = fstab_node_to_udev_node(arg_root_what);
if (!path_is_absolute(what)) {
log_debug("Skipping entry what=%s where=/sysroot type=%s", what, strna(arg_root_fstype));
return 0;
}
if (!arg_root_options)
opts = arg_root_rw > 0 ? "rw" : "ro";
else if (arg_root_rw >= 0 ||
(!mount_test_option(arg_root_options, "ro") &&
!mount_test_option(arg_root_options, "rw")))
opts = strappenda(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro");
else
opts = arg_root_options;
log_debug("Found entry what=%s where=/sysroot type=%s", what, strna(arg_root_fstype));
return add_mount(what,
"/sysroot",
arg_root_fstype,
opts,
1,
false,
false,
false,
SPECIAL_INITRD_ROOT_FS_TARGET,
"/proc/cmdline");
}
static int add_usr_mount(void) {
_cleanup_free_ char *what = NULL;
const char *opts;
if (!arg_usr_what && !arg_usr_fstype && !arg_usr_options)
return 0;
if (arg_root_what && !arg_usr_what) {
arg_usr_what = strdup(arg_root_what);
if (!arg_usr_what)
return log_oom();
}
if (arg_root_fstype && !arg_usr_fstype) {
arg_usr_fstype = strdup(arg_root_fstype);
if (!arg_usr_fstype)
return log_oom();
}
if (arg_root_options && !arg_usr_options) {
arg_usr_options = strdup(arg_root_options);
if (!arg_usr_options)
return log_oom();
}
if (!arg_usr_what || !arg_usr_options)
return 0;
what = fstab_node_to_udev_node(arg_usr_what);
if (!path_is_absolute(what)) {
log_debug("Skipping entry what=%s where=/sysroot/usr type=%s", what, strna(arg_usr_fstype));
return -1;
}
opts = arg_usr_options;
log_debug("Found entry what=%s where=/sysroot/usr type=%s", what, strna(arg_usr_fstype));
return add_mount(what,
"/sysroot/usr",
arg_usr_fstype,
opts,
1,
false,
false,
false,
SPECIAL_INITRD_ROOT_FS_TARGET,
"/proc/cmdline");
}
static int parse_proc_cmdline_item(const char *key, const char *value) {
int r;
/* root=, usr=, usrfstype= and roofstype= may occur more than once, the last
* instance should take precedence. In the case of multiple rootflags=
* or usrflags= the arguments should be concatenated */
if (STR_IN_SET(key, "fstab", "rd.fstab") && value) {
r = parse_boolean(value);
if (r < 0)
log_warning("Failed to parse fstab switch %s. Ignoring.", value);
else
arg_fstab_enabled = r;
} else if (streq(key, "root") && value) {
if (free_and_strdup(&arg_root_what, value) < 0)
return log_oom();
} else if (streq(key, "rootfstype") && value) {
if (free_and_strdup(&arg_root_fstype, value) < 0)
return log_oom();
} else if (streq(key, "rootflags") && value) {
char *o;
o = arg_root_options ?
strjoin(arg_root_options, ",", value, NULL) :
strdup(value);
if (!o)
return log_oom();
free(arg_root_options);
arg_root_options = o;
} else if (streq(key, "mount.usr") && value) {
if (free_and_strdup(&arg_usr_what, value) < 0)
return log_oom();
} else if (streq(key, "mount.usrfstype") && value) {
if (free_and_strdup(&arg_usr_fstype, value) < 0)
return log_oom();
} else if (streq(key, "mount.usrflags") && value) {
char *o;
o = arg_usr_options ?
strjoin(arg_usr_options, ",", value, NULL) :
strdup(value);
if (!o)
return log_oom();
free(arg_usr_options);
arg_usr_options = o;
} else if (streq(key, "rw") && !value)
arg_root_rw = true;
else if (streq(key, "ro") && !value)
arg_root_rw = false;
return 0;
}
int main(int argc, char *argv[]) {
int r = 0;
if (argc > 1 && argc != 4) {
log_error("This program takes three or no arguments.");
return EXIT_FAILURE;
}
if (argc > 1)
arg_dest = argv[1];
log_set_target(LOG_TARGET_SAFE);
log_parse_environment();
log_open();
umask(0022);
if (parse_proc_cmdline(parse_proc_cmdline_item) < 0)
return EXIT_FAILURE;
/* Always honour root= and usr= in the kernel command line if we are in an initrd */
if (in_initrd()) {
r = add_root_mount();
if (r == 0)
r = add_usr_mount();
}
/* Honour /etc/fstab only when that's enabled */
if (arg_fstab_enabled) {
int k;
log_debug("Parsing /etc/fstab");
/* Parse the local /etc/fstab, possibly from the initrd */
k = parse_fstab(false);
if (k < 0)
r = k;
/* If running in the initrd also parse the /etc/fstab from the host */
if (in_initrd()) {
log_debug("Parsing /sysroot/etc/fstab");
k = parse_fstab(true);
if (k < 0)
r = k;
}
}
free(arg_root_what);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}