/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include #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 "devnum-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 "initrd-util.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 "virt.h" static const char *arg_dest = NULL; static bool arg_enabled = true; static bool arg_root_enabled = true; static char *arg_root_fstype = NULL; static char *arg_root_options = NULL; static int arg_root_rw = -1; STATIC_DESTRUCTOR_REGISTER(arg_root_fstype, freep); STATIC_DESTRUCTOR_REGISTER(arg_root_options, freep); static int add_cryptsetup( const char *id, const char *what, bool rw, bool require, bool measure, char **ret_device) { #if HAVE_LIBCRYPTSETUP _cleanup_free_ char *e = NULL, *n = NULL, *d = NULL, *options = 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); if (!rw) { options = strdup("read-only"); if (!options) return log_oom(); } if (measure) { /* We only measure the root volume key into PCR 15 if we are booted with sd-stub (i.e. in a * UKI), and sd-stub measured the UKI. We do this in order not to step into people's own PCR * assignment, under the assumption that people who are fine to use sd-stub with its PCR * assignments are also OK with our PCR 15 use here. */ r = efi_stub_measured(LOG_WARNING); if (r == 0) log_debug("Will not measure volume key of volume '%s', because not booted via systemd-stub with measurements enabled.", id); else if (r > 0) { if (!strextend_with_separator(&options, ",", "tpm2-measure-pcr=yes")) return log_oom(); } } r = generator_write_cryptsetup_service_section(f, id, what, NULL, options); 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 (ret_device) { char *s; s = path_join("/dev/mapper", id); if (!s) return log_oom(); *ret_device = s; } return 0; #else return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "Partition is encrypted, but the project was compiled without libcryptsetup support"); #endif } static int add_mount( const char *id, const char *what, const char *where, const char *fstype, bool rw, bool growfs, bool measure, 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, /* require= */ true, measure, &crypto_what); if (r < 0) return r; what = crypto_what; fstype = NULL; } else if (fstype) { r = dissect_fstype_ok(fstype); if (r < 0) return log_error_errno(r, "Unable to determine of dissected file system type '%s' is permitted: %m", fstype); if (!r) return log_error_errno( SYNTHETIC_ERRNO(EIDRM), "Refusing to automatically mount uncommon file system '%s' to '%s'.", fstype, where); } 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 (growfs) { r = generator_hook_up_growfs(arg_dest, where, post); if (r < 0) return r; } if (measure) { r = generator_hook_up_pcrfs(arg_dest, where, post); if (r < 0) return r; } if (post) { r = generator_add_symlink(arg_dest, post, "requires", unit); if (r < 0) return r; } 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, /* ignore_hidden_or_backup= */ false); 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, p->growfs, /* measure= */ STR_IN_SET(id, "root", "var"), /* by default measure rootfs and /var, since they contain the "identity" of the system */ NULL, description, SPECIAL_LOCAL_FS_TARGET); } static int add_partition_swap(DissectedPartition *p) { const char *what; _cleanup_free_ char *name = NULL, *unit = NULL, *crypto_what = NULL; _cleanup_fclose_ FILE *f = NULL; int r; assert(p); assert(p->node); /* 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; } if (streq_ptr(p->fstype, "crypto_LUKS")) { r = add_cryptsetup("swap", p->node, /* rw= */ true, /* require= */ true, /* measure= */ false, &crypto_what); if (r < 0) return r; what = crypto_what; } else what = p->node; log_debug("Adding swap: %s", what); r = unit_name_from_path(what, ".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, what); if (r < 0) return r; fprintf(f, "\n" "[Swap]\n" "What=%s\n", what); 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, bool growfs, const char *options, const char *description, usec_t timeout) { _cleanup_free_ char *unit = NULL, *p = NULL; _cleanup_fclose_ FILE *f = NULL; int r; assert(id); assert(where); assert(description); r = add_mount(id, what, where, fstype, rw, growfs, /* measure= */ false, options, 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 = path_join(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); return generator_add_symlink(arg_dest, SPECIAL_LOCAL_FS_TARGET, "wants", unit); } static const char *esp_or_xbootldr_options(const DissectedPartition *p) { assert(p); /* Discovered ESP and XBOOTLDR partition are always hardened with "noexec,nosuid,nodev". * 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 (!p->fstype || streq(p->fstype, "vfat")) return "umask=0077,noexec,nosuid,nodev"; return "noexec,nosuid,nodev"; } static int add_partition_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, /* rw= */ true, /* growfs= */ false, esp_or_xbootldr_options(p), "Boot Loader Partition", 120 * USEC_PER_SEC); } #if ENABLE_EFI static int add_partition_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, /* rw= */ true, /* growfs= */ false, esp_or_xbootldr_options(p), "EFI System Partition Automount", 120 * USEC_PER_SEC); } #else static int add_partition_esp(DissectedPartition *p, bool has_xbootldr) { return 0; } #endif static int add_partition_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 HAVE_LIBCRYPTSETUP /* 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", /* rw= */ true, /* require= */ false, /* measure= */ true, NULL); #else return 0; #endif } #endif static int add_root_mount(void) { #if ENABLE_EFI int r; if (!is_efi_boot()) { log_debug("Not an 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" : "/", arg_root_fstype, /* rw= */ arg_root_rw > 0, /* growfs= */ false, /* measure= */ true, arg_root_options, "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_(dissected_image_unrefp) DissectedImage *m = NULL; _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL; _cleanup_free_ char *devname = NULL; int r, k; r = block_get_whole_disk(devnum, &devnum); if (r < 0) return log_debug_errno(r, "Failed to get whole block device for " DEVNUM_FORMAT_STR ": %m", DEVNUM_FORMAT_VAL(devnum)); r = devname_from_devnum(S_IFBLK, devnum, &devname); if (r < 0) return log_debug_errno(r, "Failed to get device node of " DEVNUM_FORMAT_STR ": %m", DEVNUM_FORMAT_VAL(devnum)); /* Let's take a LOCK_SH lock on the block device, in case udevd is already running. If we don't take * the lock, udevd might end up issuing BLKRRPART in the middle, and we don't want that, since that * might remove all partitions while we are operating on them. */ r = loop_device_open_from_path(devname, O_RDONLY, LOCK_SH, &loop); if (r < 0) return log_debug_errno(r, "Failed to open %s: %m", devname); r = dissect_loop_device( loop, NULL, NULL, DISSECT_IMAGE_GPT_ONLY| DISSECT_IMAGE_USR_NO_ROOT| DISSECT_IMAGE_DISKSEQ_DEVNODE, /* NB! Unlike most other places where we dissect block devices we do not use * DISSECT_IMAGE_ADD_PARTITION_DEVICES here: we want that the kernel finds the * devices, and udev probes them before we mount them via .mount units much later * on. And thus we also don't set DISSECT_IMAGE_PIN_PARTITION_DEVICES here, because * we don't actually mount anything immediately. */ &m); if (r == -ENOPKG) { log_debug_errno(r, "No suitable partition table found on block device %s, ignoring.", devname); return 0; } if (r < 0) return log_error_errno(r, "Failed to dissect partition table of block device %s: %m", devname); if (m->partitions[PARTITION_SWAP].found) { k = add_partition_swap(m->partitions + PARTITION_SWAP); if (k < 0) r = k; } if (m->partitions[PARTITION_XBOOTLDR].found) { k = add_partition_xbootldr(m->partitions + PARTITION_XBOOTLDR); if (k < 0) r = k; } if (m->partitions[PARTITION_ESP].found) { k = add_partition_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_partition_root_rw(m->partitions + PARTITION_ROOT); if (k < 0) r = k; } return r; } static int add_mounts(void) { dev_t devno; int r; r = blockdev_get_root(LOG_ERR, &devno); if (r < 0) return r; if (r == 0) { log_debug("Skipping automatic GPT dissection logic, root file system not backed by a (single) whole block device."); return 0; } 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 (streq(key, "rootfstype")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_root_fstype, value); } else if (streq(key, "rootflags")) { if (proc_cmdline_value_missing(key, value)) return 0; if (!strextend_with_separator(&arg_root_options, ",", value)) return log_oom(); } 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);