/***
This file is part of systemd.
Copyright 2013 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 .
***/
#include
#include
#include
#include
#include "libudev.h"
#include "sd-id128.h"
#include "alloc-util.h"
#include "blkid-util.h"
#include "btrfs-util.h"
#include "dirent-util.h"
#include "dissect-image.h"
#include "efivars.h"
#include "fd-util.h"
#include "fileio.h"
#include "fstab-util.h"
#include "generator.h"
#include "gpt.h"
#include "missing.h"
#include "mkdir.h"
#include "mount-util.h"
#include "parse-util.h"
#include "path-util.h"
#include "proc-cmdline.h"
#include "special.h"
#include "stat-util.h"
#include "string-util.h"
#include "udev-util.h"
#include "unit-name.h"
#include "util.h"
#include "virt.h"
static const char *arg_dest = "/tmp";
static bool arg_enabled = true;
static bool arg_root_enabled = true;
static bool arg_root_rw = false;
static int add_cryptsetup(const char *id, const char *what, bool rw, bool require, char **device) {
_cleanup_free_ char *e = NULL, *n = NULL, *p = NULL, *d = NULL, *to = NULL;
_cleanup_fclose_ FILE *f = NULL;
char *from, *ret;
int r;
assert(id);
assert(what);
r = unit_name_from_path(what, ".device", &d);
if (r < 0)
return log_error_errno(r, "Failed to generate unit name: %m");
e = unit_name_escape(id);
if (!e)
return log_oom();
r = unit_name_build("systemd-cryptsetup", e, ".service", &n);
if (r < 0)
return log_error_errno(r, "Failed to generate unit name: %m");
p = strjoin(arg_dest, "/", n);
if (!p)
return log_oom();
f = fopen(p, "wxe");
if (!f)
return log_error_errno(errno, "Failed to create unit file %s: %m", p);
fprintf(f,
"# Automatically generated by systemd-gpt-auto-generator\n\n"
"[Unit]\n"
"Description=Cryptography Setup for %%I\n"
"Documentation=man:systemd-gpt-auto-generator(8) man:systemd-cryptsetup@.service(8)\n"
"DefaultDependencies=no\n"
"Conflicts=umount.target\n"
"BindsTo=dev-mapper-%%i.device %s\n"
"Before=umount.target cryptsetup.target\n"
"After=%s\n"
"IgnoreOnIsolate=true\n"
"[Service]\n"
"Type=oneshot\n"
"RemainAfterExit=yes\n"
"TimeoutSec=0\n" /* the binary handles timeouts anyway */
"ExecStart=" SYSTEMD_CRYPTSETUP_PATH " attach '%s' '%s' '' '%s'\n"
"ExecStop=" SYSTEMD_CRYPTSETUP_PATH " detach '%s'\n",
d, d,
id, what, rw ? "" : "read-only",
id);
r = fflush_and_check(f);
if (r < 0)
return log_error_errno(r, "Failed to write file %s: %m", p);
from = strjoina("../", n);
to = strjoin(arg_dest, "/", d, ".wants/", n);
if (!to)
return log_oom();
mkdir_parents_label(to, 0755);
if (symlink(from, to) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", to);
if (require) {
free(to);
to = strjoin(arg_dest, "/cryptsetup.target.requires/", n);
if (!to)
return log_oom();
mkdir_parents_label(to, 0755);
if (symlink(from, to) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", to);
free(to);
to = strjoin(arg_dest, "/dev-mapper-", e, ".device.requires/", n);
if (!to)
return log_oom();
mkdir_parents_label(to, 0755);
if (symlink(from, to) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", to);
}
free(p);
p = strjoin(arg_dest, "/dev-mapper-", e, ".device.d/50-job-timeout-sec-0.conf");
if (!p)
return log_oom();
mkdir_parents_label(p, 0755);
r = write_string_file(p,
"# Automatically generated by systemd-gpt-auto-generator\n\n"
"[Unit]\n"
"JobTimeoutSec=0\n",
WRITE_STRING_FILE_CREATE); /* the binary handles timeouts anyway */
if (r < 0)
return log_error_errno(r, "Failed to write device drop-in: %m");
ret = strappend("/dev/mapper/", id);
if (!ret)
return log_oom();
if (device)
*device = ret;
return 0;
}
static int add_mount(
const char *id,
const char *what,
const char *where,
const char *fstype,
bool rw,
const char *options,
const char *description,
const char *post) {
_cleanup_free_ char *unit = NULL, *lnk = NULL, *crypto_what = NULL, *p = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(id);
assert(what);
assert(where);
assert(description);
log_debug("Adding %s: %s %s", where, what, strna(fstype));
if (streq_ptr(fstype, "crypto_LUKS")) {
r = add_cryptsetup(id, what, rw, true, &crypto_what);
if (r < 0)
return r;
what = crypto_what;
fstype = NULL;
}
r = unit_name_from_path(where, ".mount", &unit);
if (r < 0)
return log_error_errno(r, "Failed to generate unit name: %m");
p = strjoin(arg_dest, "/", unit);
if (!p)
return log_oom();
f = fopen(p, "wxe");
if (!f)
return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
fprintf(f,
"# Automatically generated by systemd-gpt-auto-generator\n\n"
"[Unit]\n"
"Description=%s\n"
"Documentation=man:systemd-gpt-auto-generator(8)\n",
description);
if (post)
fprintf(f, "Before=%s\n", post);
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 (fstype)
fprintf(f, "Type=%s\n", fstype);
if (options)
fprintf(f, "Options=%s,%s\n", options, rw ? "rw" : "ro");
else
fprintf(f, "Options=%s\n", rw ? "rw" : "ro");
r = fflush_and_check(f);
if (r < 0)
return log_error_errno(r, "Failed to write unit file %s: %m", p);
if (post) {
lnk = strjoin(arg_dest, "/", post, ".requires/", unit);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(p, lnk) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
}
return 0;
}
static bool path_is_busy(const char *where) {
int r;
/* already a mountpoint; generators run during reload */
r = path_is_mount_point(where, NULL, AT_SYMLINK_FOLLOW);
if (r > 0)
return false;
/* the directory might not exist on a stateless system */
if (r == -ENOENT)
return false;
if (r < 0)
return true;
/* not a mountpoint but it contains files */
if (dir_is_empty(where) <= 0)
return true;
return false;
}
static int add_partition_mount(
DissectedPartition *p,
const char *id,
const char *where,
const char *description) {
assert(p);
if (path_is_busy(where)) {
log_debug("%s already populated, ignoring.", where);
return 0;
}
return add_mount(
id,
p->node,
where,
p->fstype,
p->rw,
NULL,
description,
SPECIAL_LOCAL_FS_TARGET);
}
static int add_swap(const char *path) {
_cleanup_free_ char *name = NULL, *unit = NULL, *lnk = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(path);
log_debug("Adding swap: %s", path);
r = unit_name_from_path(path, ".swap", &name);
if (r < 0)
return log_error_errno(r, "Failed to generate unit name: %m");
unit = strjoin(arg_dest, "/", name);
if (!unit)
return log_oom();
f = fopen(unit, "wxe");
if (!f)
return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
fprintf(f,
"# Automatically generated by systemd-gpt-auto-generator\n\n"
"[Unit]\n"
"Description=Swap Partition\n"
"Documentation=man:systemd-gpt-auto-generator(8)\n\n"
"[Swap]\n"
"What=%s\n",
path);
r = fflush_and_check(f);
if (r < 0)
return log_error_errno(r, "Failed to write unit file %s: %m", unit);
lnk = strjoin(arg_dest, "/" SPECIAL_SWAP_TARGET ".wants/", name);
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;
}
#ifdef ENABLE_EFI
static int add_automount(
const char *id,
const char *what,
const char *where,
const char *fstype,
bool rw,
const char *options,
const char *description,
usec_t timeout) {
_cleanup_free_ char *unit = NULL, *lnk = NULL;
_cleanup_free_ char *opt, *p = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(id);
assert(where);
assert(description);
if (options)
opt = strjoin(options, ",noauto");
else
opt = strdup("noauto");
if (!opt)
return log_oom();
r = add_mount(id,
what,
where,
fstype,
rw,
opt,
description,
NULL);
if (r < 0)
return r;
r = unit_name_from_path(where, ".automount", &unit);
if (r < 0)
return log_error_errno(r, "Failed to generate unit name: %m");
p = strjoin(arg_dest, "/", unit);
if (!p)
return log_oom();
f = fopen(p, "wxe");
if (!f)
return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
fprintf(f,
"# Automatically generated by systemd-gpt-auto-generator\n\n"
"[Unit]\n"
"Description=%s\n"
"Documentation=man:systemd-gpt-auto-generator(8)\n"
"[Automount]\n"
"Where=%s\n"
"TimeoutIdleSec="USEC_FMT"\n",
description,
where,
timeout / USEC_PER_SEC);
r = fflush_and_check(f);
if (r < 0)
return log_error_errno(r, "Failed to write unit file %s: %m", p);
lnk = strjoin(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/", unit);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(p, lnk) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
return 0;
}
static int add_esp(DissectedPartition *p) {
const char *esp;
int r;
assert(p);
if (in_initrd()) {
log_debug("In initrd, ignoring the ESP.");
return 0;
}
/* If /efi exists we'll use that. Otherwise we'll use /boot, as that's usually the better choice */
esp = access("/efi/", F_OK) >= 0 ? "/efi" : "/boot";
/* We create an .automount which is not overridden by the .mount from the fstab generator. */
if (fstab_is_mount_point(esp)) {
log_debug("%s specified in fstab, ignoring.", esp);
return 0;
}
if (path_is_busy(esp)) {
log_debug("%s already populated, ignoring.", esp);
return 0;
}
if (is_efi_boot()) {
sd_id128_t loader_uuid;
/* If this is an EFI boot, be extra careful, and only mount the ESP if it was the ESP used for booting. */
r = efi_loader_get_device_part_uuid(&loader_uuid);
if (r == -ENOENT) {
log_debug("EFI loader partition unknown.");
return 0;
}
if (r < 0)
return log_error_errno(r, "Failed to read ESP partition UUID: %m");
if (!sd_id128_equal(p->uuid, loader_uuid)) {
log_debug("Partition for %s does not appear to be the partition we are booted from.", esp);
return 0;
}
} else
log_debug("Not an EFI boot, skipping ESP check.");
return add_automount("boot",
p->node,
esp,
p->fstype,
true,
"umask=0077",
"EFI System Partition Automount",
120 * USEC_PER_SEC);
}
#else
static int add_esp(const char *what) {
return 0;
}
#endif
static int open_parent(dev_t devnum, int *ret) {
_cleanup_udev_device_unref_ struct udev_device *d = NULL;
_cleanup_udev_unref_ struct udev *udev = NULL;
const char *name, *devtype, *node;
struct udev_device *parent;
dev_t pn;
int fd;
assert(ret);
udev = udev_new();
if (!udev)
return log_oom();
d = udev_device_new_from_devnum(udev, 'b', devnum);
if (!d)
return log_oom();
name = udev_device_get_devnode(d);
if (!name)
name = udev_device_get_syspath(d);
if (!name) {
log_debug("Device %u:%u does not have a name, ignoring.", major(devnum), minor(devnum));
goto not_found;
}
parent = udev_device_get_parent(d);
if (!parent) {
log_debug("%s: not a partitioned device, ignoring.", name);
goto not_found;
}
/* Does it have a devtype? */
devtype = udev_device_get_devtype(parent);
if (!devtype) {
log_debug("%s: parent doesn't have a device type, ignoring.", name);
goto not_found;
}
/* Is this a disk or a partition? We only care for disks... */
if (!streq(devtype, "disk")) {
log_debug("%s: parent isn't a raw disk, ignoring.", name);
goto not_found;
}
/* Does it have a device node? */
node = udev_device_get_devnode(parent);
if (!node) {
log_debug("%s: parent device does not have device node, ignoring.", name);
goto not_found;
}
log_debug("%s: root device %s.", name, node);
pn = udev_device_get_devnum(parent);
if (major(pn) == 0) {
log_debug("%s: parent device is not a proper block device, ignoring.", name);
goto not_found;
}
fd = open(node, O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0)
return log_error_errno(errno, "Failed to open %s: %m", node);
*ret = fd;
return 1;
not_found:
*ret = -1;
return 0;
}
static int enumerate_partitions(dev_t devnum) {
_cleanup_close_ int fd = -1;
_cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
int r, k;
r = open_parent(devnum, &fd);
if (r <= 0)
return r;
r = dissect_image(fd, NULL, 0, DISSECT_IMAGE_GPT_ONLY, &m);
if (r == -ENOPKG) {
log_debug_errno(r, "No suitable partition table found, ignoring.");
return 0;
}
if (r < 0)
return log_error_errno(r, "Failed to dissect: %m");
if (m->partitions[PARTITION_SWAP].found) {
k = add_swap(m->partitions[PARTITION_SWAP].node);
if (k < 0)
r = k;
}
if (m->partitions[PARTITION_ESP].found) {
k = add_esp(m->partitions + PARTITION_ESP);
if (k < 0)
r = k;
}
if (m->partitions[PARTITION_HOME].found) {
k = add_partition_mount(m->partitions + PARTITION_HOME, "home", "/home", "Home Partition");
if (k < 0)
r = k;
}
if (m->partitions[PARTITION_SRV].found) {
k = add_partition_mount(m->partitions + PARTITION_SRV, "srv", "/srv", "Server Data Partition");
if (k < 0)
r = k;
}
return r;
}
static int get_block_device(const char *path, dev_t *dev) {
struct stat st;
struct statfs sfs;
assert(path);
assert(dev);
/* Get's the block device directly backing a file system. If
* the block device is encrypted, returns the device mapper
* block device. */
if (lstat(path, &st))
return -errno;
if (major(st.st_dev) != 0) {
*dev = st.st_dev;
return 1;
}
if (statfs(path, &sfs) < 0)
return -errno;
if (F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC))
return btrfs_get_block_device(path, dev);
return 0;
}
static int get_block_device_harder(const char *path, dev_t *dev) {
_cleanup_closedir_ DIR *d = NULL;
_cleanup_free_ char *p = NULL, *t = NULL;
struct dirent *de, *found = NULL;
const char *q;
unsigned maj, min;
dev_t dt;
int r;
assert(path);
assert(dev);
/* Gets the backing block device for a file system, and
* handles LUKS encrypted file systems, looking for its
* immediate parent, if there is one. */
r = get_block_device(path, &dt);
if (r <= 0)
return r;
if (asprintf(&p, "/sys/dev/block/%u:%u/slaves", major(dt), minor(dt)) < 0)
return -ENOMEM;
d = opendir(p);
if (!d) {
if (errno == ENOENT)
goto fallback;
return -errno;
}
FOREACH_DIRENT_ALL(de, d, return -errno) {
if (STR_IN_SET(de->d_name, ".", ".."))
continue;
if (!IN_SET(de->d_type, DT_LNK, DT_UNKNOWN))
continue;
if (found) {
_cleanup_free_ char *u = NULL, *v = NULL, *a = NULL, *b = NULL;
/* We found a device backed by multiple other devices. We don't really support automatic
* discovery on such setups, with the exception of dm-verity partitions. In this case there are
* two backing devices: the data partition and the hash partition. We are fine with such
* setups, however, only if both partitions are on the same physical device. Hence, let's
* verify this. */
u = strjoin(p, "/", de->d_name, "/../dev");
if (!u)
return -ENOMEM;
v = strjoin(p, "/", found->d_name, "/../dev");
if (!v)
return -ENOMEM;
r = read_one_line_file(u, &a);
if (r < 0) {
log_debug_errno(r, "Failed to read %s: %m", u);
goto fallback;
}
r = read_one_line_file(v, &b);
if (r < 0) {
log_debug_errno(r, "Failed to read %s: %m", v);
goto fallback;
}
/* Check if the parent device is the same. If not, then the two backing devices are on
* different physical devices, and we don't support that. */
if (!streq(a, b))
goto fallback;
}
found = de;
}
if (!found)
goto fallback;
q = strjoina(p, "/", found->d_name, "/dev");
r = read_one_line_file(q, &t);
if (r == -ENOENT)
goto fallback;
if (r < 0)
return r;
if (sscanf(t, "%u:%u", &maj, &min) != 2)
return -EINVAL;
if (maj == 0)
goto fallback;
*dev = makedev(maj, min);
return 1;
fallback:
*dev = dt;
return 1;
}
static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
int r;
assert(key);
if (STR_IN_SET(key, "systemd.gpt_auto", "rd.systemd.gpt_auto")) {
r = value ? parse_boolean(value) : 1;
if (r < 0)
log_warning("Failed to parse gpt-auto switch \"%s\". Ignoring.", value);
else
arg_enabled = r;
} else if (streq(key, "root")) {
if (proc_cmdline_value_missing(key, value))
return 0;
/* Disable root disk logic if there's a root= value
* specified (unless it happens to be "gpt-auto") */
arg_root_enabled = streq(value, "gpt-auto");
} else if (streq(key, "roothash")) {
if (proc_cmdline_value_missing(key, value))
return 0;
/* Disable root disk logic if there's roothash= defined (i.e. verity enabled) */
arg_root_enabled = false;
} else if (streq(key, "rw") && !value)
arg_root_rw = true;
else if (streq(key, "ro") && !value)
arg_root_rw = false;
return 0;
}
#ifdef ENABLE_EFI
static int add_root_cryptsetup(void) {
/* If a device /dev/gpt-auto-root-luks appears, then make it pull in systemd-cryptsetup-root.service, which
* sets it up, and causes /dev/gpt-auto-root to appear which is all we are looking for. */
return add_cryptsetup("root", "/dev/gpt-auto-root-luks", true, false, NULL);
}
#endif
static int add_root_mount(void) {
#ifdef ENABLE_EFI
int r;
if (!is_efi_boot()) {
log_debug("Not a EFI boot, not creating root mount.");
return 0;
}
r = efi_loader_get_device_part_uuid(NULL);
if (r == -ENOENT) {
log_debug("EFI loader partition unknown, exiting.");
return 0;
} else if (r < 0)
return log_error_errno(r, "Failed to read ESP partition UUID: %m");
/* OK, we have an ESP partition, this is fantastic, so let's
* wait for a root device to show up. A udev rule will create
* the link for us under the right name. */
if (in_initrd()) {
r = generator_write_initrd_root_device_deps(arg_dest, "/dev/gpt-auto-root");
if (r < 0)
return 0;
r = add_root_cryptsetup();
if (r < 0)
return r;
}
return add_mount(
"root",
"/dev/gpt-auto-root",
in_initrd() ? "/sysroot" : "/",
NULL,
arg_root_rw,
NULL,
"Root Partition",
in_initrd() ? SPECIAL_INITRD_ROOT_FS_TARGET : SPECIAL_LOCAL_FS_TARGET);
#else
return 0;
#endif
}
static int add_mounts(void) {
dev_t devno;
int r;
r = get_block_device_harder("/", &devno);
if (r < 0)
return log_error_errno(r, "Failed to determine block device of root file system: %m");
if (r == 0) {
r = get_block_device_harder("/usr", &devno);
if (r < 0)
return log_error_errno(r, "Failed to determine block device of /usr file system: %m");
if (r == 0) {
log_debug("Neither root nor /usr file system are on a (single) block device.");
return 0;
}
}
return enumerate_partitions(devno);
}
int main(int argc, char *argv[]) {
int r = 0, k;
if (argc > 1 && argc != 4) {
log_error("This program takes three or no arguments.");
return EXIT_FAILURE;
}
if (argc > 1)
arg_dest = argv[3];
log_set_target(LOG_TARGET_SAFE);
log_parse_environment();
log_open();
umask(0022);
if (detect_container() > 0) {
log_debug("In a container, exiting.");
return EXIT_SUCCESS;
}
r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
if (r < 0)
log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
if (!arg_enabled) {
log_debug("Disabled, exiting.");
return EXIT_SUCCESS;
}
if (arg_root_enabled)
r = add_root_mount();
if (!in_initrd()) {
k = add_mounts();
if (k < 0)
r = k;
}
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}