blob: f9d0ca54214749a2ce6f94ad6c43d04158d16c77 [file] [log] [blame] [raw]
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <stdlib.h>
#include <unistd.h>
#include "sd-device.h"
#include "sd-id128.h"
#include "alloc-util.h"
#include "blkid-util.h"
#include "blockdev-util.h"
#include "btrfs-util.h"
#include "device-util.h"
#include "dirent-util.h"
#include "dissect-image.h"
#include "dropin.h"
#include "efi-loader.h"
#include "fd-util.h"
#include "fileio.h"
#include "fs-util.h"
#include "fstab-util.h"
#include "generator.h"
#include "gpt.h"
#include "mkdir.h"
#include "mountpoint-util.h"
#include "parse-util.h"
#include "path-util.h"
#include "proc-cmdline.h"
#include "special.h"
#include "specifier.h"
#include "stat-util.h"
#include "string-util.h"
#include "strv.h"
#include "unit-name.h"
#include "util.h"
#include "virt.h"
static const char *arg_dest = NULL;
static bool arg_enabled = true;
static bool arg_root_enabled = true;
static int arg_root_rw = -1;
static int open_parent_block_device(dev_t devnum, int *ret_fd) {
_cleanup_(sd_device_unrefp) sd_device *d = NULL;
const char *name, *devtype, *node;
sd_device *parent;
dev_t pn;
int fd, r;
assert(ret_fd);
r = sd_device_new_from_devnum(&d, 'b', devnum);
if (r < 0)
return log_debug_errno(r, "Failed to open device: %m");
if (sd_device_get_devname(d, &name) < 0) {
r = sd_device_get_syspath(d, &name);
if (r < 0) {
log_device_debug_errno(d, r, "Device %u:%u does not have a name, ignoring: %m",
major(devnum), minor(devnum));
return 0;
}
}
r = sd_device_get_parent(d, &parent);
if (r < 0) {
log_device_debug_errno(d, r, "Not a partitioned device, ignoring: %m");
return 0;
}
/* Does it have a devtype? */
r = sd_device_get_devtype(parent, &devtype);
if (r < 0) {
log_device_debug_errno(parent, r, "Parent doesn't have a device type, ignoring: %m");
return 0;
}
/* Is this a disk or a partition? We only care for disks... */
if (!streq(devtype, "disk")) {
log_device_debug(parent, "Parent isn't a raw disk, ignoring.");
return 0;
}
/* Does it have a device node? */
r = sd_device_get_devname(parent, &node);
if (r < 0) {
log_device_debug_errno(parent, r, "Parent device does not have device node, ignoring: %m");
return 0;
}
log_device_debug(d, "Root device %s.", node);
r = sd_device_get_devnum(parent, &pn);
if (r < 0) {
log_device_debug_errno(parent, r, "Parent device is not a proper block device, ignoring: %m");
return 0;
}
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 = fd;
return 1;
}
static int add_cryptsetup(const char *id, const char *what, bool rw, bool require, char **device) {
_cleanup_free_ char *e = NULL, *n = NULL, *d = NULL;
_cleanup_fclose_ FILE *f = NULL;
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");
r = generator_open_unit_file(arg_dest, NULL, n, &f);
if (r < 0)
return r;
r = generator_write_cryptsetup_unit_section(f, NULL);
if (r < 0)
return r;
fprintf(f,
"Before=umount.target cryptsetup.target\n"
"Conflicts=umount.target\n"
"BindsTo=%s\n"
"After=%s\n",
d, d);
r = generator_write_cryptsetup_service_section(f, id, what, NULL, rw ? NULL : "read-only");
if (r < 0)
return r;
r = fflush_and_check(f);
if (r < 0)
return log_error_errno(r, "Failed to write file %s: %m", n);
r = generator_add_symlink(arg_dest, d, "wants", n);
if (r < 0)
return r;
const char *dmname;
dmname = strjoina("dev-mapper-", e, ".device");
if (require) {
r = generator_add_symlink(arg_dest, "cryptsetup.target", "requires", n);
if (r < 0)
return r;
r = generator_add_symlink(arg_dest, dmname, "requires", n);
if (r < 0)
return r;
}
r = write_drop_in_format(arg_dest, dmname, 50, "job-timeout",
"# Automatically generated by systemd-gpt-auto-generator\n\n"
"[Unit]\n"
"JobTimeoutSec=0"); /* the binary handles timeouts anyway */
if (r < 0)
log_warning_errno(r, "Failed to write device timeout drop-in, ignoring: %m");
if (device) {
char *ret;
ret = path_join("/dev/mapper", id);
if (!ret)
return log_oom();
*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, *crypto_what = NULL, *p = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
/* Note that we don't apply specifier escaping on the input strings here, since we know they are not configured
* externally, but all originate from our own sources here, and hence we know they contain no % characters that
* could potentially be understood as specifiers. */
assert(id);
assert(what);
assert(where);
assert(description);
log_debug("Adding %s: %s fstype=%s", where, what, fstype ?: "(any)");
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 = path_join(empty_to_root(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;
r = generator_write_blockdev_dependency(f, what);
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)
return generator_add_symlink(arg_dest, post, "requires", unit);
return 0;
}
static int 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 log_warning_errno(r, "Cannot check if \"%s\" is a mount point: %m", where);
/* not a mountpoint but it contains files */
r = dir_is_empty(where);
if (r < 0)
return log_warning_errno(r, "Cannot check if \"%s\" is empty: %m", where);
if (r > 0)
return false;
log_debug("\"%s\" already populated, ignoring.", where);
return true;
}
static int add_partition_mount(
DissectedPartition *p,
const char *id,
const char *where,
const char *description) {
int r;
assert(p);
r = path_is_busy(where);
if (r != 0)
return r < 0 ? r : 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;
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(path);
/* Disable the swap auto logic if at least one swap is defined in /etc/fstab, see #6192. */
r = fstab_has_fstype("swap");
if (r < 0)
return log_error_errno(r, "Failed to parse fstab: %m");
if (r > 0) {
log_debug("swap specified in fstab, ignoring.");
return 0;
}
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 = path_join(empty_to_root(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");
r = generator_write_blockdev_dependency(f, path);
if (r < 0)
return r;
fprintf(f,
"\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);
return generator_add_symlink(arg_dest, SPECIAL_SWAP_TARGET, "wants", name);
}
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;
_cleanup_fclose_ FILE *f = NULL;
const char *opt = "noauto", *p;
int r;
assert(id);
assert(where);
assert(description);
if (options)
opt = strjoina(options, ",", opt);
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 = prefix_roota(arg_dest, unit);
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);
return generator_add_symlink(arg_dest, SPECIAL_LOCAL_FS_TARGET, "wants", unit);
}
static const char *esp_or_xbootldr_options(const DissectedPartition *p) {
assert(p);
/* if we probed vfat or have no idea about the file system then assume these file systems are vfat
* and thus understand "umask=0077". If we detected something else then don't specify any options and
* use kernel defaults. */
if (!p->fstype || streq(p->fstype, "vfat"))
return "umask=0077";
return NULL;
}
static int add_xbootldr(DissectedPartition *p) {
int r;
assert(p);
if (in_initrd()) {
log_debug("In initrd, ignoring the XBOOTLDR partition.");
return 0;
}
r = fstab_is_mount_point("/boot");
if (r < 0)
return log_error_errno(r, "Failed to parse fstab: %m");
if (r > 0) {
log_debug("/boot specified in fstab, ignoring XBOOTLDR partition.");
return 0;
}
r = path_is_busy("/boot");
if (r < 0)
return r;
if (r > 0)
return 0;
return add_automount("boot",
p->node,
"/boot",
p->fstype,
true,
esp_or_xbootldr_options(p),
"Boot Loader Partition",
120 * USEC_PER_SEC);
}
#if ENABLE_EFI
static int add_esp(DissectedPartition *p, bool has_xbootldr) {
const char *esp_path = NULL, *id = NULL;
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, but
* only if there's no explicit XBOOTLDR partition around. */
if (access("/efi", F_OK) < 0) {
if (errno != ENOENT)
return log_error_errno(errno, "Failed to determine whether /efi exists: %m");
/* Use /boot as fallback, but only if there's no XBOOTLDR partition */
if (!has_xbootldr) {
esp_path = "/boot";
id = "boot";
}
}
if (!esp_path)
esp_path = "/efi";
if (!id)
id = "efi";
/* We create an .automount which is not overridden by the .mount from the fstab generator. */
r = fstab_is_mount_point(esp_path);
if (r < 0)
return log_error_errno(r, "Failed to parse fstab: %m");
if (r > 0) {
log_debug("%s specified in fstab, ignoring.", esp_path);
return 0;
}
r = path_is_busy(esp_path);
if (r < 0)
return r;
if (r > 0)
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.", p->node);
return 0;
}
} else
log_debug("Not an EFI boot, skipping ESP check.");
return add_automount(id,
p->node,
esp_path,
p->fstype,
true,
esp_or_xbootldr_options(p),
"EFI System Partition Automount",
120 * USEC_PER_SEC);
}
#else
static int add_esp(DissectedPartition *p, bool has_xbootldr) {
return 0;
}
#endif
static int add_root_rw(DissectedPartition *p) {
const char *path;
int r;
assert(p);
if (in_initrd()) {
log_debug("In initrd, not generating drop-in for systemd-remount-fs.service.");
return 0;
}
if (arg_root_rw >= 0) {
log_debug("Parameter ro/rw specified on kernel command line, not generating drop-in for systemd-remount-fs.service.");
return 0;
}
if (!p->rw) {
log_debug("Root partition marked read-only in GPT partition table, not generating drop-in for systemd-remount-fs.service.");
return 0;
}
(void) generator_enable_remount_fs_service(arg_dest);
path = strjoina(arg_dest, "/systemd-remount-fs.service.d/50-remount-rw.conf");
r = write_string_file(path,
"# Automatically generated by systemd-gpt-generator\n\n"
"[Service]\n"
"Environment=SYSTEMD_REMOUNT_ROOT_RW=1\n",
WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_NOFOLLOW|WRITE_STRING_FILE_MKDIR_0755);
if (r < 0)
return log_error_errno(r, "Failed to write drop-in file %s: %m", path);
return 0;
}
#if 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) {
#if 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_notice("EFI loader partition unknown, exiting.\n"
"(The boot loader did not set EFI variable LoaderDevicePartUUID.)");
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;
}
/* Note that we do not need to enable systemd-remount-fs.service here. If
* /etc/fstab exists, systemd-fstab-generator will pull it in for us. */
return add_mount(
"root",
"/dev/gpt-auto-root",
in_initrd() ? "/sysroot" : "/",
NULL,
arg_root_rw > 0,
NULL,
"Root Partition",
in_initrd() ? SPECIAL_INITRD_ROOT_FS_TARGET : SPECIAL_LOCAL_FS_TARGET);
#else
return 0;
#endif
}
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_block_device(devnum, &fd);
if (r <= 0)
return r;
r = dissect_image(fd, NULL, NULL, DISSECT_IMAGE_GPT_ONLY|DISSECT_IMAGE_NO_UDEV, &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_XBOOTLDR].found) {
k = add_xbootldr(m->partitions + PARTITION_XBOOTLDR);
if (k < 0)
r = k;
}
if (m->partitions[PARTITION_ESP].found) {
k = add_esp(m->partitions + PARTITION_ESP, m->partitions[PARTITION_XBOOTLDR].found);
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;
}
if (m->partitions[PARTITION_VAR].found) {
k = add_partition_mount(m->partitions + PARTITION_VAR, "var", "/var", "Variable Data Partition");
if (k < 0)
r = k;
}
if (m->partitions[PARTITION_TMP].found) {
k = add_partition_mount(m->partitions + PARTITION_TMP, "var-tmp", "/var/tmp", "Temporary Data Partition");
if (k < 0)
r = k;
}
if (m->partitions[PARTITION_ROOT].found) {
k = add_root_rw(m->partitions + PARTITION_ROOT);
if (k < 0)
r = k;
}
return r;
}
static int add_mounts(void) {
dev_t devno;
int r;
r = get_block_device_harder("/", &devno);
if (r == -EUCLEAN)
return btrfs_log_dev_root(LOG_ERR, r, "root file system");
if (r < 0)
return log_error_errno(r, "Failed to determine block device of root file system: %m");
if (r == 0) { /* Not backed by block device */
r = get_block_device_harder("/usr", &devno);
if (r == -EUCLEAN)
return btrfs_log_dev_root(LOG_ERR, r, "/usr");
if (r < 0)
return log_error_errno(r, "Failed to determine block device of /usr file system: %m");
if (r == 0) {
_cleanup_free_ char *p = NULL;
mode_t m;
/* If the root mount has been replaced by some form of volatile file system (overlayfs), the
* original root block device node is symlinked in /run/systemd/volatile-root. Let's read that
* here. */
r = readlink_malloc("/run/systemd/volatile-root", &p);
if (r == -ENOENT) {
log_debug("Neither root nor /usr file system are on a (single) block device.");
return 0;
}
if (r < 0)
return log_error_errno(r, "Failed to read symlink /run/systemd/volatile-root: %m");
r = device_path_parse_major_minor(p, &m, &devno);
if (r < 0)
return log_error_errno(r, "Failed to parse major/minor device node: %m");
if (!S_ISBLK(m))
return log_error_errno(SYNTHETIC_ERRNO(ENOTBLK), "Volatile root device is of wrong type.");
}
}
return enumerate_partitions(devno);
}
static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
int r;
assert(key);
if (proc_cmdline_key_streq(key, "systemd.gpt_auto") ||
proc_cmdline_key_streq(key, "rd.systemd.gpt_auto")) {
r = value ? parse_boolean(value) : 1;
if (r < 0)
log_warning_errno(r, "Failed to parse gpt-auto switch \"%s\", ignoring: %m", value);
else
arg_enabled = r;
} else if (proc_cmdline_key_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") */
if (!streq(value, "gpt-auto")) {
arg_root_enabled = false;
log_debug("Disabling root partition auto-detection, root= is defined.");
}
} else if (proc_cmdline_key_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 (proc_cmdline_key_streq(key, "rw") && !value)
arg_root_rw = true;
else if (proc_cmdline_key_streq(key, "ro") && !value)
arg_root_rw = false;
return 0;
}
static int run(const char *dest, const char *dest_early, const char *dest_late) {
int r, k;
assert_se(arg_dest = dest_late);
if (detect_container() > 0) {
log_debug("In a container, exiting.");
return 0;
}
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 0;
}
if (arg_root_enabled)
r = add_root_mount();
if (!in_initrd()) {
k = add_mounts();
if (r >= 0)
r = k;
}
return r;
}
DEFINE_MAIN_GENERATOR_FUNCTION(run);