Systemd/src/shared/generator.c
Lennart Poettering 98bad05e75 generators: be more careful when writing unit settings that support specifier expansion
Let's always escape strings we receive from the user before writing them
out to unit file settings that suppor specifier expansion, so that user
strings are transported as-is.
2017-11-29 12:32:57 +01:00

280 lines
9.6 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
Copyright 2014 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 <errno.h>
#include <unistd.h>
#include "alloc-util.h"
#include "dropin.h"
#include "escape.h"
#include "fd-util.h"
#include "fileio.h"
#include "fstab-util.h"
#include "generator.h"
#include "log.h"
#include "macro.h"
#include "mkdir.h"
#include "path-util.h"
#include "special.h"
#include "specifier.h"
#include "string-util.h"
#include "time-util.h"
#include "unit-name.h"
#include "util.h"
int generator_add_symlink(const char *root, const char *dst, const char *dep_type, const char *src) {
/* Adds a symlink from <dst>.<dep_type>.d/ to ../<src> */
const char *from, *to;
from = strjoina("../", src);
to = strjoina(root, "/", dst, ".", dep_type, "/", src);
mkdir_parents_label(to, 0755);
if (symlink(from, to) < 0)
if (errno != EEXIST)
return log_error_errno(errno, "Failed to create symlink \"%s\": %m", to);
return 0;
}
static int write_fsck_sysroot_service(const char *dir, const char *what) {
_cleanup_free_ char *device = NULL, *escaped = NULL, *escaped2 = NULL;
_cleanup_fclose_ FILE *f = NULL;
const char *unit;
int r;
escaped = specifier_escape(what);
if (!escaped)
return log_oom();
escaped2 = cescape(escaped);
if (!escaped2)
return log_oom();
unit = strjoina(dir, "/systemd-fsck-root.service");
log_debug("Creating %s", unit);
r = unit_name_from_path(what, ".device", &device);
if (r < 0)
return log_error_errno(r, "Failed to convert device \"%s\" to unit name: %m", what);
f = fopen(unit, "wxe");
if (!f)
return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
fprintf(f,
"# Automatically generated by %1$s\n\n"
"[Unit]\n"
"Documentation=man:systemd-fsck-root.service(8)\n"
"Description=File System Check on %2$s\n"
"DefaultDependencies=no\n"
"BindsTo=%3$s\n"
"After=initrd-root-device.target local-fs-pre.target %3$s\n"
"Before=shutdown.target\n"
"\n"
"[Service]\n"
"Type=oneshot\n"
"RemainAfterExit=yes\n"
"ExecStart=" SYSTEMD_FSCK_PATH " %4$s\n"
"TimeoutSec=0\n",
program_invocation_short_name,
escaped,
device,
escaped2);
r = fflush_and_check(f);
if (r < 0)
return log_error_errno(r, "Failed to write unit file %s: %m", unit);
return 0;
}
int generator_write_fsck_deps(
FILE *f,
const char *dir,
const char *what,
const char *where,
const char *fstype) {
int r;
assert(f);
assert(dir);
assert(what);
assert(where);
if (!is_device_path(what)) {
log_warning("Checking was requested for \"%s\", but it is not a device.", what);
return 0;
}
if (!isempty(fstype) && !streq(fstype, "auto")) {
r = fsck_exists(fstype);
if (r < 0)
log_warning_errno(r, "Checking was requested for %s, but couldn't detect if fsck.%s may be used, proceeding: %m", what, fstype);
else if (r == 0) {
/* treat missing check as essentially OK */
log_debug("Checking was requested for %s, but fsck.%s does not exist.", what, fstype);
return 0;
}
}
if (path_equal(where, "/")) {
const char *lnk;
lnk = strjoina(dir, "/" SPECIAL_LOCAL_FS_TARGET ".wants/systemd-fsck-root.service");
mkdir_parents(lnk, 0755);
if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-fsck-root.service", lnk) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
} else {
_cleanup_free_ char *_fsck = NULL;
const char *fsck;
if (in_initrd() && path_equal(where, "/sysroot")) {
r = write_fsck_sysroot_service(dir, what);
if (r < 0)
return r;
fsck = "systemd-fsck-root.service";
} else {
r = unit_name_from_path_instance("systemd-fsck", what, ".service", &_fsck);
if (r < 0)
return log_error_errno(r, "Failed to create fsck service name: %m");
fsck = _fsck;
}
fprintf(f,
"Requires=%1$s\n"
"After=%1$s\n",
fsck);
}
return 0;
}
int generator_write_timeouts(
const char *dir,
const char *what,
const char *where,
const char *opts,
char **filtered) {
/* Allow configuration how long we wait for a device that
* backs a mount point to show up. This is useful to support
* endless device timeouts for devices that show up only after
* user input, like crypto devices. */
_cleanup_free_ char *node = NULL, *unit = NULL, *timeout = NULL;
usec_t u;
int r;
r = fstab_filter_options(opts, "comment=systemd.device-timeout\0"
"x-systemd.device-timeout\0",
NULL, &timeout, filtered);
if (r <= 0)
return r;
r = parse_sec_fix_0(timeout, &u);
if (r < 0) {
log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout);
return 0;
}
node = fstab_node_to_udev_node(what);
if (!node)
return log_oom();
if (!is_device_path(node)) {
log_warning("x-systemd.device-timeout ignored for %s", what);
return 0;
}
r = unit_name_from_path(node, ".device", &unit);
if (r < 0)
return log_error_errno(r, "Failed to make unit name from path: %m");
return write_drop_in_format(dir, unit, 50, "device-timeout",
"# Automatically generated by %s\n\n"
"[Unit]\n"
"JobRunningTimeoutSec=%s",
program_invocation_short_name,
timeout);
}
int generator_write_device_deps(
const char *dir,
const char *what,
const char *where,
const char *opts) {
/* fstab records that specify _netdev option should apply the network
* ordering on the actual device depending on network connection. If we
* are not mounting real device (NFS, CIFS), we rely on _netdev effect
* on the mount unit itself. */
_cleanup_free_ char *node = NULL, *unit = NULL;
int r;
if (!fstab_test_option(opts, "_netdev\0"))
return 0;
node = fstab_node_to_udev_node(what);
if (!node)
return log_oom();
/* Nothing to apply dependencies to. */
if (!is_device_path(node))
return 0;
r = unit_name_from_path(node, ".device", &unit);
if (r < 0)
return log_error_errno(r, "Failed to make unit name from path: %m");
/* See mount_add_default_dependencies for explanation why we create such
* dependencies. */
return write_drop_in_format(dir, unit, 50, "netdev-dependencies",
"# Automatically generated by %s\n\n"
"[Unit]\n"
"After=" SPECIAL_NETWORK_ONLINE_TARGET " " SPECIAL_NETWORK_TARGET "\n"
"Wants=" SPECIAL_NETWORK_ONLINE_TARGET "\n",
program_invocation_short_name);
}
int generator_write_initrd_root_device_deps(const char *dir, const char *what) {
_cleanup_free_ char *unit = NULL;
int r;
r = unit_name_from_path(what, ".device", &unit);
if (r < 0)
return log_error_errno(r, "Failed to make unit name from path: %m");
return write_drop_in_format(dir, SPECIAL_INITRD_ROOT_DEVICE_TARGET, 50, "root-device",
"# Automatically generated by %s\n\n"
"[Unit]\n"
"Requires=%s\n"
"After=%s",
program_invocation_short_name,
unit,
unit);
}