picnoir/Systemd
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity
Systemd/src/fstab-generator/fstab-generator.c
Zbigniew Jędrzejewski-Szmek d15d0333be Add new function to filter fstab options 
This fixes parsing of options in shared/generator.c. Existing code
had some issues:

- it would treate whitespace and semicolons as seperators. fstab(5)
  is pretty clear that only commas matter. And the syntax does
  not allow for spaces to be inserted in the field in fstab.
  Whitespace might be escaped, but then it should not seperate
  options. Treat whitespace and semicolons as any other character.
- it assumed that x-systemd.device-timeout would always be followed
  by "=". But this is not guaranteed, hasmntopt will return this
  option even if there's no value. Uninitialized memory could be read.
- some error paths would log, and inconsistently, some would just
  return an error code.

Filtering is split out to a separate function and tests are added.

Similar code paths in other places are adjusted to use the new function.
2015-01-11 23:41:41 -05:00

610 lines
20 KiB
C
Raw Blame History

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2012 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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 "fstab-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 add_swap(
const char *what,
struct mntent *me,
bool noauto,
bool nofail) {
_cleanup_free_ char *name = NULL, *unit = NULL, *lnk = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r, pri = -1;
assert(what);
assert(me);
if (access("/proc/swaps", F_OK) < 0) {
log_info("Swap not supported, ignoring fstab swap entry for %s.", what);
return 0;
}
if (detect_container(NULL) > 0) {
log_info("Running in a container, ignoring fstab swap entry for %s.", what);
return 0;
}
r = fstab_find_pri(me->mnt_opts, &pri);
if (r < 0)
return log_error_errno(r, "Failed to parse priority: %m");
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_errno(errno, "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)
return log_error_errno(r, "Failed to write unit file %s: %m", unit);
/* 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,
nofail ? ".wants/" : ".requires/", name, NULL);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(unit, lnk) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
}
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_errno(errno, "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))
return log_error_errno(errno, "Failed to write unit file %s: %m", unit);
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)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
}
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)
return log_error_errno(errno, "Failed to create unit file %s: %m", automount_unit);
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))
return log_error_errno(errno, "Failed to write unit file %s: %m", automount_unit);
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)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
}
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_errno(errno, "Failed to open %s: %m", fstab_path);
return -errno;
}
while ((me = getmntent(f))) {
_cleanup_free_ char *where = NULL, *what = NULL;
bool noauto, nofail;
int k;
if (initrd && !mount_in_initrd(me))
continue;
what = fstab_node_to_udev_node(me->mnt_fsname);
if (!what)
return log_oom();
if (is_device_path(what) && path_is_read_only_fs("sys") > 0) {
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);
noauto = !!hasmntopt(me, "noauto");
nofail = !!hasmntopt(me, "nofail");
log_debug("Found entry what=%s where=%s type=%s nofail=%s noauto=%s",
what, where, me->mnt_type,
yes_no(noauto), yes_no(nofail));
if (streq(me->mnt_type, "swap"))
k = add_swap(what, me, noauto, nofail);
else {
bool automount;
const char *post;
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 ||
!fstab_test_option(arg_root_options, "ro\0" "rw\0"))
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)
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;
}
if (!arg_usr_options)
opts = arg_root_rw > 0 ? "rw" : "ro";
else if (!fstab_test_option(arg_usr_options, "ro\0" "rw\0"))
opts = strappenda(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro");
else
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);
r = parse_proc_cmdline(parse_proc_cmdline_item);
if (r < 0)
log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
/* 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);
free(arg_root_fstype);
free(arg_root_options);
free(arg_usr_what);
free(arg_usr_fstype);
free(arg_usr_options);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}
Reference in a new issue View git blame Copy permalink