src/gpt-auto-generator/gpt-auto-generator.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <stdlib.h>
   4 #include <sys/file.h>
   5 #include <unistd.h>
   6
   7 #include "sd-device.h"
   8 #include "sd-id128.h"
   9
  10 #include "alloc-util.h"
  11 #include "blkid-util.h"
  12 #include "blockdev-util.h"
  13 #include "btrfs-util.h"
  14 #include "device-util.h"
  15 #include "devnum-util.h"
  16 #include "dirent-util.h"
  17 #include "dissect-image.h"
  18 #include "dropin.h"
  19 #include "efi-loader.h"
  20 #include "fd-util.h"
  21 #include "fileio.h"
  22 #include "fs-util.h"
  23 #include "fstab-util.h"
  24 #include "generator.h"
  25 #include "gpt.h"
  26 #include "image-policy.h"
  27 #include "initrd-util.h"
  28 #include "mountpoint-util.h"
  29 #include "parse-util.h"
  30 #include "path-util.h"
  31 #include "proc-cmdline.h"
  32 #include "special.h"
  33 #include "specifier.h"
  34 #include "stat-util.h"
  35 #include "string-util.h"
  36 #include "strv.h"
  37 #include "unit-name.h"
  38 #include "virt.h"
  39
  40 static const char *arg_dest = NULL;
  41 static bool arg_enabled = true;
  42 static bool arg_root_enabled = true;
  43 static bool arg_swap_enabled = true;
  44 static char *arg_root_fstype = NULL;
  45 static char *arg_root_options = NULL;
  46 static int arg_root_rw = -1;
  47 static ImagePolicy *arg_image_policy = NULL;
  48
  49 STATIC_DESTRUCTOR_REGISTER(arg_image_policy, image_policy_freep);
  50
  51 STATIC_DESTRUCTOR_REGISTER(arg_root_fstype, freep);
  52 STATIC_DESTRUCTOR_REGISTER(arg_root_options, freep);
  53
  54 static int add_cryptsetup(
  55                 const char *id,
  56                 const char *what,
  57                 bool rw,
  58                 bool require,
  59                 bool measure,
  60                 char **ret_device) {
  61
  62 #if HAVE_LIBCRYPTSETUP
  63         _cleanup_free_ char *e = NULL, *n = NULL, *d = NULL, *options = NULL;
  64         _cleanup_fclose_ FILE *f = NULL;
  65         int r;
  66
  67         assert(id);
  68         assert(what);
  69
  70         r = unit_name_from_path(what, ".device", &d);
  71         if (r < 0)
  72                 return log_error_errno(r, "Failed to generate unit name: %m");
  73
  74         e = unit_name_escape(id);
  75         if (!e)
  76                 return log_oom();
  77
  78         r = unit_name_build("systemd-cryptsetup", e, ".service", &n);
  79         if (r < 0)
  80                 return log_error_errno(r, "Failed to generate unit name: %m");
  81
  82         r = generator_open_unit_file(arg_dest, /* source = */ NULL, n, &f);
  83         if (r < 0)
  84                 return r;
  85
  86         r = generator_write_cryptsetup_unit_section(f, NULL);
  87         if (r < 0)
  88                 return r;
  89
  90         fprintf(f,
  91                 "Before=umount.target cryptsetup.target\n"
  92                 "Conflicts=umount.target\n"
  93                 "BindsTo=%s\n"
  94                 "After=%s\n",
  95                 d, d);
  96
  97         if (!rw) {
  98                 options = strdup("read-only");
  99                 if (!options)
 100                         return log_oom();
 101         }
 102
 103         r = efi_measured_uki(LOG_WARNING);
 104         if (r > 0)
 105                 /* Enable TPM2 based unlocking automatically, if we have a TPM. See #30176. */
 106                 if (!strextend_with_separator(&options, ",", "tpm2-device=auto"))
 107                         return log_oom();
 108
 109         if (measure) {
 110                 /* We only measure the root volume key into PCR 15 if we are booted with sd-stub (i.e. in a
 111                  * UKI), and sd-stub measured the UKI. We do this in order not to step into people's own PCR
 112                  * assignment, under the assumption that people who are fine to use sd-stub with its PCR
 113                  * assignments are also OK with our PCR 15 use here. */
 114                 if (r > 0)
 115                         if (!strextend_with_separator(&options, ",", "tpm2-measure-pcr=yes"))
 116                                 return log_oom();
 117                 if (r == 0)
 118                         log_debug("Will not measure volume key of volume '%s', not booted via systemd-stub with measurements enabled.", id);
 119         }
 120
 121         r = generator_write_cryptsetup_service_section(f, id, what, NULL, options);
 122         if (r < 0)
 123                 return r;
 124
 125         r = fflush_and_check(f);
 126         if (r < 0)
 127                 return log_error_errno(r, "Failed to write file %s: %m", n);
 128
 129         r = generator_add_symlink(arg_dest, d, "wants", n);
 130         if (r < 0)
 131                 return r;
 132
 133         const char *dmname = strjoina("dev-mapper-", e, ".device");
 134
 135         if (require) {
 136                 r = generator_add_symlink(arg_dest, "cryptsetup.target", "requires", n);
 137                 if (r < 0)
 138                         return r;
 139
 140                 r = generator_add_symlink(arg_dest, dmname, "requires", n);
 141                 if (r < 0)
 142                         return r;
 143         }
 144
 145         r = write_drop_in_format(arg_dest, dmname, 50, "job-timeout",
 146                                  "# Automatically generated by systemd-gpt-auto-generator\n\n"
 147                                  "[Unit]\n"
 148                                  "JobTimeoutSec=infinity"); /* the binary handles timeouts anyway */
 149         if (r < 0)
 150                 log_warning_errno(r, "Failed to write device timeout drop-in, ignoring: %m");
 151
 152         if (ret_device) {
 153                 char *s;
 154
 155                 s = path_join("/dev/mapper", id);
 156                 if (!s)
 157                         return log_oom();
 158
 159                 *ret_device = s;
 160         }
 161
 162         return 0;
 163 #else
 164         return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
 165                                "Partition is encrypted, but systemd-gpt-auto-generator was compiled without libcryptsetup support");
 166 #endif
 167 }
 168
 169 static int add_mount(
 170                 const char *id,
 171                 const char *what,
 172                 const char *where,
 173                 const char *fstype,
 174                 bool rw,
 175                 bool growfs,
 176                 bool measure,
 177                 const char *options,
 178                 const char *description,
 179                 const char *post) {
 180
 181         _cleanup_free_ char *unit = NULL, *crypto_what = NULL;
 182         _cleanup_fclose_ FILE *f = NULL;
 183         int r;
 184
 185         /* Note that we don't apply specifier escaping on the input strings here, since we know they are not configured
 186          * externally, but all originate from our own sources here, and hence we know they contain no % characters that
 187          * could potentially be understood as specifiers. */
 188
 189         assert(id);
 190         assert(what);
 191         assert(where);
 192         assert(description);
 193
 194         log_debug("Adding %s: %s fstype=%s", where, what, fstype ?: "(any)");
 195
 196         if (streq_ptr(fstype, "crypto_LUKS")) {
 197                 r = add_cryptsetup(id, what, rw, /* require= */ true, measure, &crypto_what);
 198                 if (r < 0)
 199                         return r;
 200
 201                 what = crypto_what;
 202                 fstype = NULL;
 203         } else if (fstype) {
 204                 r = dissect_fstype_ok(fstype);
 205                 if (r < 0)
 206                         return log_error_errno(r, "Unable to determine of dissected file system type '%s' is permitted: %m", fstype);
 207                 if (!r)
 208                         return log_error_errno(
 209                                         SYNTHETIC_ERRNO(EIDRM),
 210                                         "Refusing to automatically mount uncommon file system '%s' to '%s'.",
 211                                         fstype, where);
 212         }
 213
 214         r = unit_name_from_path(where, ".mount", &unit);
 215         if (r < 0)
 216                 return log_error_errno(r, "Failed to generate unit name: %m");
 217
 218         r = generator_open_unit_file(arg_dest, /* source = */ NULL, unit, &f);
 219         if (r < 0)
 220                 return r;
 221
 222         fprintf(f,
 223                 "[Unit]\n"
 224                 "Description=%s\n"
 225                 "Documentation=man:systemd-gpt-auto-generator(8)\n",
 226                 description);
 227
 228         if (post)
 229                 fprintf(f, "Before=%s\n", post);
 230
 231         r = generator_write_fsck_deps(f, arg_dest, what, where, fstype);
 232         if (r < 0)
 233                 return r;
 234
 235         r = generator_write_blockdev_dependency(f, what);
 236         if (r < 0)
 237                 return r;
 238
 239         fprintf(f,
 240                 "\n"
 241                 "[Mount]\n"
 242                 "What=%s\n"
 243                 "Where=%s\n",
 244                 what, where);
 245
 246         if (fstype)
 247                 fprintf(f, "Type=%s\n", fstype);
 248
 249         if (options)
 250                 fprintf(f, "Options=%s\n", options);
 251
 252         r = fflush_and_check(f);
 253         if (r < 0)
 254                 return log_error_errno(r, "Failed to write unit %s: %m", unit);
 255
 256         if (growfs) {
 257                 r = generator_hook_up_growfs(arg_dest, where, post);
 258                 if (r < 0)
 259                         return r;
 260         }
 261
 262         if (measure) {
 263                 r = generator_hook_up_pcrfs(arg_dest, where, post);
 264                 if (r < 0)
 265                         return r;
 266         }
 267
 268         if (post) {
 269                 r = generator_add_symlink(arg_dest, post, "requires", unit);
 270                 if (r < 0)
 271                         return r;
 272         }
 273
 274         return 0;
 275 }
 276
 277 static int path_is_busy(const char *where) {
 278         int r;
 279
 280         assert(where);
 281
 282         /* already a mountpoint; generators run during reload */
 283         r = path_is_mount_point_full(where, /* root = */ NULL, AT_SYMLINK_FOLLOW);
 284         if (r > 0)
 285                 return false;
 286         /* The directory will be created by the mount or automount unit when it is started. */
 287         if (r == -ENOENT)
 288                 return false;
 289
 290         if (r < 0)
 291                 return log_warning_errno(r, "Cannot check if \"%s\" is a mount point: %m", where);
 292
 293         /* not a mountpoint but it contains files */
 294         r = dir_is_empty(where, /* ignore_hidden_or_backup= */ false);
 295         if (r == -ENOTDIR) {
 296                 log_debug("\"%s\" is not a directory, ignoring.", where);
 297                 return true;
 298         } else if (r < 0)
 299                 return log_warning_errno(r, "Cannot check if \"%s\" is empty: %m", where);
 300         else if (r == 0) {
 301                 log_debug("\"%s\" already populated, ignoring.", where);
 302                 return true;
 303         }
 304
 305         return false;
 306 }
 307
 308 static int add_partition_mount(
 309                 PartitionDesignator d,
 310                 DissectedPartition *p,
 311                 const char *id,
 312                 const char *where,
 313                 const char *description) {
 314
 315         _cleanup_free_ char *options = NULL;
 316         int r;
 317
 318         assert(p);
 319
 320         r = path_is_busy(where);
 321         if (r != 0)
 322                 return r < 0 ? r : 0;
 323
 324         r = partition_pick_mount_options(
 325                         d,
 326                         dissected_partition_fstype(p),
 327                         p->rw,
 328                         /* discard= */ true,
 329                         &options,
 330                         /* ret_ms_flags= */ NULL);
 331         if (r < 0)
 332                 return r;
 333
 334         return add_mount(
 335                         id,
 336                         p->node,
 337                         where,
 338                         p->fstype,
 339                         p->rw,
 340                         p->growfs,
 341                         /* measure= */ STR_IN_SET(id, "root", "var"), /* by default measure rootfs and /var, since they contain the "identity" of the system */
 342                         options,
 343                         description,
 344                         SPECIAL_LOCAL_FS_TARGET);
 345 }
 346
 347 static int add_partition_swap(DissectedPartition *p) {
 348         const char *what;
 349         _cleanup_free_ char *name = NULL, *crypto_what = NULL;
 350         _cleanup_fclose_ FILE *f = NULL;
 351         int r;
 352
 353         assert(p);
 354         assert(p->node);
 355
 356         if (!arg_swap_enabled)
 357                 return 0;
 358
 359         /* Disable the swap auto logic if at least one swap is defined in /etc/fstab, see #6192. */
 360         r = fstab_has_fstype("swap");
 361         if (r < 0)
 362                 return log_error_errno(r, "Failed to parse fstab: %m");
 363         if (r > 0) {
 364                 log_debug("swap specified in fstab, ignoring.");
 365                 return 0;
 366         }
 367
 368         if (streq_ptr(p->fstype, "crypto_LUKS")) {
 369                 r = add_cryptsetup("swap", p->node, /* rw= */ true, /* require= */ true, /* measure= */ false, &crypto_what);
 370                 if (r < 0)
 371                         return r;
 372                 what = crypto_what;
 373         } else
 374                 what = p->node;
 375
 376         log_debug("Adding swap: %s", what);
 377
 378         r = unit_name_from_path(what, ".swap", &name);
 379         if (r < 0)
 380                 return log_error_errno(r, "Failed to generate unit name: %m");
 381
 382         r = generator_open_unit_file(arg_dest, /* source = */ NULL, name, &f);
 383         if (r < 0)
 384                 return r;
 385
 386         fprintf(f,
 387                 "[Unit]\n"
 388                 "Description=Swap Partition\n"
 389                 "Documentation=man:systemd-gpt-auto-generator(8)\n");
 390
 391         r = generator_write_blockdev_dependency(f, what);
 392         if (r < 0)
 393                 return r;
 394
 395         fprintf(f,
 396                 "\n"
 397                 "[Swap]\n"
 398                 "What=%s\n",
 399                 what);
 400
 401         r = fflush_and_check(f);
 402         if (r < 0)
 403                 return log_error_errno(r, "Failed to write unit %s: %m", name);
 404
 405         return generator_add_symlink(arg_dest, SPECIAL_SWAP_TARGET, "wants", name);
 406 }
 407
 408 static int add_automount(
 409                 const char *id,
 410                 const char *what,
 411                 const char *where,
 412                 const char *fstype,
 413                 bool rw,
 414                 bool growfs,
 415                 const char *options,
 416                 const char *description,
 417                 usec_t timeout) {
 418
 419         _cleanup_free_ char *unit = NULL;
 420         _cleanup_fclose_ FILE *f = NULL;
 421         int r;
 422
 423         assert(id);
 424         assert(where);
 425         assert(description);
 426
 427         r = add_mount(id,
 428                       what,
 429                       where,
 430                       fstype,
 431                       rw,
 432                       growfs,
 433                       /* measure= */ false,
 434                       options,
 435                       description,
 436                       NULL);
 437         if (r < 0)
 438                 return r;
 439
 440         r = unit_name_from_path(where, ".automount", &unit);
 441         if (r < 0)
 442                 return log_error_errno(r, "Failed to generate unit name: %m");
 443
 444         r = generator_open_unit_file(arg_dest, /* source = */ NULL, unit, &f);
 445         if (r < 0)
 446                 return r;
 447
 448         fprintf(f,
 449                 "[Unit]\n"
 450                 "Description=%s\n"
 451                 "Documentation=man:systemd-gpt-auto-generator(8)\n"
 452                 "[Automount]\n"
 453                 "Where=%s\n"
 454                 "TimeoutIdleSec="USEC_FMT"\n",
 455                 description,
 456                 where,
 457                 timeout / USEC_PER_SEC);
 458
 459         r = fflush_and_check(f);
 460         if (r < 0)
 461                 return log_error_errno(r, "Failed to write unit %s: %m", unit);
 462
 463         return generator_add_symlink(arg_dest, SPECIAL_LOCAL_FS_TARGET, "wants", unit);
 464 }
 465
 466 static int add_partition_xbootldr(DissectedPartition *p) {
 467         _cleanup_free_ char *options = NULL;
 468         int r;
 469
 470         assert(p);
 471
 472         if (in_initrd()) {
 473                 log_debug("In initrd, ignoring the XBOOTLDR partition.");
 474                 return 0;
 475         }
 476
 477         r = path_is_busy("/boot");
 478         if (r < 0)
 479                 return r;
 480         if (r > 0)
 481                 return 0;
 482
 483         r = partition_pick_mount_options(
 484                         PARTITION_XBOOTLDR,
 485                         dissected_partition_fstype(p),
 486                         /* rw= */ true,
 487                         /* discard= */ false,
 488                         &options,
 489                         /* ret_ms_flags= */ NULL);
 490         if (r < 0)
 491                 return log_error_errno(r, "Failed to determine default mount options for /boot/: %m");
 492
 493         return add_automount(
 494                         "boot",
 495                         p->node,
 496                         "/boot",
 497                         p->fstype,
 498                         /* rw= */ true,
 499                         /* growfs= */ false,
 500                         options,
 501                         "Boot Loader Partition",
 502                         120 * USEC_PER_SEC);
 503 }
 504
 505 #if ENABLE_EFI
 506 static bool slash_boot_exists(void) {
 507         static int cache = -1;
 508
 509         if (cache >= 0)
 510                 return cache;
 511
 512         if (access("/boot", F_OK) >= 0)
 513                 return (cache = true);
 514         if (errno != ENOENT)
 515                 log_error_errno(errno, "Failed to determine whether /boot/ exists, assuming no: %m");
 516         else
 517                 log_debug_errno(errno, "/boot/: %m");
 518         return (cache = false);
 519 }
 520
 521 static int add_partition_esp(DissectedPartition *p, bool has_xbootldr) {
 522         const char *esp_path = NULL, *id = NULL;
 523         _cleanup_free_ char *options = NULL;
 524         int r;
 525
 526         assert(p);
 527
 528         if (in_initrd()) {
 529                 log_debug("In initrd, ignoring the ESP.");
 530                 return 0;
 531         }
 532
 533         /* Check if there's an existing fstab entry for ESP. If so, we just skip the gpt-auto logic. */
 534         r = fstab_has_node(p->node);
 535         if (r < 0)
 536                 return log_error_errno(r,
 537                                        "Failed to check if fstab entry for device '%s' exists: %m", p->node);
 538         if (r > 0)
 539                 return 0;
 540
 541         /* If /boot/ is present, unused, and empty, we'll take that.
 542          * Otherwise, if /efi/ is unused and empty (or missing), we'll take that.
 543          * Otherwise, we do nothing. */
 544         if (!has_xbootldr && slash_boot_exists()) {
 545                 r = path_is_busy("/boot");
 546                 if (r < 0)
 547                         return r;
 548                 if (r == 0) {
 549                         esp_path = "/boot";
 550                         id = "boot";
 551                 }
 552         }
 553
 554         if (!esp_path) {
 555                 r = path_is_busy("/efi");
 556                 if (r < 0)
 557                         return r;
 558                 if (r > 0)
 559                         return 0;
 560
 561                 esp_path = "/efi";
 562                 id = "efi";
 563         }
 564
 565         r = partition_pick_mount_options(
 566                         PARTITION_ESP,
 567                         dissected_partition_fstype(p),
 568                         /* rw= */ true,
 569                         /* discard= */ false,
 570                         &options,
 571                         /* ret_ms_flags= */ NULL);
 572         if (r < 0)
 573                 return log_error_errno(r, "Failed to determine default mount options for %s: %m", esp_path);
 574
 575         return add_automount(
 576                         id,
 577                         p->node,
 578                         esp_path,
 579                         p->fstype,
 580                         /* rw= */ true,
 581                         /* growfs= */ false,
 582                         options,
 583                         "EFI System Partition Automount",
 584                         120 * USEC_PER_SEC);
 585 }
 586 #else
 587 static int add_partition_esp(DissectedPartition *p, bool has_xbootldr) {
 588         return 0;
 589 }
 590 #endif
 591
 592 static int add_partition_root_rw(DissectedPartition *p) {
 593         const char *path;
 594         int r;
 595
 596         assert(p);
 597         assert(!in_initrd());
 598
 599         /* Invoked on the main system (not initrd), to honour GPT flag 60 on the root fs (ro) */
 600
 601         if (arg_root_rw >= 0) {
 602                 log_debug("Parameter ro/rw specified on kernel command line, not generating drop-in for systemd-remount-fs.service.");
 603                 return 0;
 604         }
 605
 606         if (!p->rw) {
 607                 log_debug("Root partition marked read-only in GPT partition table, not generating drop-in for systemd-remount-fs.service.");
 608                 return 0;
 609         }
 610
 611         r = generator_enable_remount_fs_service(arg_dest);
 612         if (r < 0)
 613                 return r;
 614
 615         path = strjoina(arg_dest, "/systemd-remount-fs.service.d/50-remount-rw.conf");
 616
 617         r = write_string_file(path,
 618                               "# Automatically generated by systemd-gpt-auto-generator\n\n"
 619                               "[Service]\n"
 620                               "Environment=SYSTEMD_REMOUNT_ROOT_RW=1\n",
 621                               WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_NOFOLLOW|WRITE_STRING_FILE_MKDIR_0755);
 622         if (r < 0)
 623                 return log_error_errno(r, "Failed to write drop-in file %s: %m", path);
 624
 625         return 0;
 626 }
 627
 628 static int add_partition_root_growfs(DissectedPartition *p) {
 629
 630         assert(p);
 631         assert(!in_initrd());
 632
 633         /* Invoked on the main system (not initrd), to honour GPT flag 59 on the root fs (growfs) */
 634
 635         if (!p->growfs) {
 636                 log_debug("Root partition not marked for growing the file system in the GPT partition table, not generating drop-in for systemd-growfs-root.service.");
 637                 return 0;
 638         }
 639
 640         return generator_hook_up_growfs(arg_dest, "/", SPECIAL_LOCAL_FS_TARGET);
 641 }
 642
 643 static int add_partition_root_flags(DissectedPartition *p) {
 644         int r = 0;
 645
 646         assert(p);
 647         assert(!in_initrd());
 648
 649         RET_GATHER(r, add_partition_root_growfs(p));
 650         RET_GATHER(r, add_partition_root_rw(p));
 651
 652         return r;
 653 }
 654
 655 #if ENABLE_EFI
 656 static int add_root_cryptsetup(void) {
 657 #if HAVE_LIBCRYPTSETUP
 658
 659         /* If a device /dev/gpt-auto-root-luks appears, then make it pull in systemd-cryptsetup-root.service, which
 660          * sets it up, and causes /dev/gpt-auto-root to appear which is all we are looking for. */
 661
 662         return add_cryptsetup("root", "/dev/gpt-auto-root-luks", /* rw= */ true, /* require= */ false, /* measure= */ true, NULL);
 663 #else
 664         return 0;
 665 #endif
 666 }
 667 #endif
 668
 669 static int add_root_mount(void) {
 670 #if ENABLE_EFI
 671         _cleanup_free_ char *options = NULL;
 672         int r;
 673
 674         if (!is_efi_boot()) {
 675                 log_debug("Not an EFI boot, not creating root mount.");
 676                 return 0;
 677         }
 678
 679         r = efi_loader_get_device_part_uuid(NULL);
 680         if (r == -ENOENT) {
 681                 log_notice("EFI loader partition unknown, exiting.\n"
 682                            "(The boot loader did not set EFI variable LoaderDevicePartUUID.)");
 683                 return 0;
 684         } else if (r < 0)
 685                 return log_error_errno(r, "Failed to read loader partition UUID: %m");
 686
 687         /* OK, we have an ESP/XBOOTLDR partition, this is fantastic, so let's wait for a root device to show up.
 688          * A udev rule will create the link for us under the right name. */
 689
 690         if (in_initrd()) {
 691                 r = generator_write_initrd_root_device_deps(arg_dest, "/dev/gpt-auto-root");
 692                 if (r < 0)
 693                         return 0;
 694
 695                 r = add_root_cryptsetup();
 696                 if (r < 0)
 697                         return r;
 698         }
 699
 700         /* Note that we do not need to enable systemd-remount-fs.service here. If /etc/fstab exists,
 701          * systemd-fstab-generator will pull it in for us, and otherwise add_partition_root_flags() will do
 702          * it, after the initrd transition. */
 703
 704         r = partition_pick_mount_options(
 705                         PARTITION_ROOT,
 706                         arg_root_fstype,
 707                         arg_root_rw > 0,
 708                         /* discard= */ true,
 709                         &options,
 710                         /* ret_ms_flags= */ NULL);
 711         if (r < 0)
 712                 return log_error_errno(r, "Failed to pick root mount options: %m");
 713
 714         if (arg_root_options)
 715                 if (!strextend_with_separator(&options, ",", arg_root_options))
 716                         return log_oom();
 717
 718         return add_mount(
 719                         "root",
 720                         "/dev/gpt-auto-root",
 721                         in_initrd() ? "/sysroot" : "/",
 722                         arg_root_fstype,
 723                         /* rw= */ arg_root_rw > 0,
 724                         /* growfs= */ false,
 725                         /* measure= */ true,
 726                         options,
 727                         "Root Partition",
 728                         in_initrd() ? SPECIAL_INITRD_ROOT_FS_TARGET : SPECIAL_LOCAL_FS_TARGET);
 729 #else
 730         return 0;
 731 #endif
 732 }
 733
 734 static int process_loader_partitions(DissectedPartition *esp, DissectedPartition *xbootldr) {
 735         sd_id128_t loader_uuid;
 736         int r;
 737
 738         assert(esp);
 739         assert(xbootldr);
 740
 741         /* If any paths in fstab look similar to our favorite paths for ESP or XBOOTLDR, we just exit
 742          * early. We also don't bother with cases where one is configured explicitly and the other shall be
 743          * mounted automatically. */
 744
 745         r = fstab_has_mount_point_prefix_strv(STRV_MAKE("/boot", "/efi"));
 746         if (r > 0) {
 747                 log_debug("Found mount entries in the /boot/ or /efi/ hierarchies in fstab, not generating ESP or XBOOTLDR mounts.");
 748                 return 0;
 749         }
 750         if (r < 0)
 751                 log_debug_errno(r, "Failed to check fstab existing paths, ignoring: %m");
 752
 753         if (!is_efi_boot()) {
 754                 log_debug("Not an EFI boot, skipping loader partition UUID check.");
 755                 goto mount;
 756         }
 757
 758         /* Let's check if LoaderDevicePartUUID points to either ESP or XBOOTLDR. We prefer it pointing
 759          * to the ESP, but we accept XBOOTLDR too. If it points to neither of them, don't mount any
 760          * loader partitions, since they are not the ones used for booting. */
 761
 762         r = efi_loader_get_device_part_uuid(&loader_uuid);
 763         if (r == -ENOENT) {
 764                 log_debug_errno(r, "EFI loader partition unknown, skipping ESP and XBOOTLDR mounts.");
 765                 return 0;
 766         }
 767         if (r < 0)
 768                 return log_debug_errno(r, "Failed to read loader partition UUID, ignoring: %m");
 769
 770         if (esp->found && sd_id128_equal(esp->uuid, loader_uuid))
 771                 goto mount;
 772
 773         if (xbootldr->found && sd_id128_equal(xbootldr->uuid, loader_uuid)) {
 774                 log_debug("LoaderDevicePartUUID points to XBOOTLDR partition.");
 775                 goto mount;
 776         }
 777
 778         log_debug("LoaderDevicePartUUID points to neither ESP nor XBOOTLDR, ignoring.");
 779         return 0;
 780
 781 mount:
 782         r = 0;
 783
 784         if (xbootldr->found)
 785                 RET_GATHER(r, add_partition_xbootldr(xbootldr));
 786         if (esp->found)
 787                 RET_GATHER(r, add_partition_esp(esp, xbootldr->found));
 788
 789         return r;
 790 }
 791
 792 static int enumerate_partitions(dev_t devnum) {
 793         _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
 794         _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
 795         _cleanup_free_ char *devname = NULL;
 796         int r;
 797
 798         assert(!in_initrd());
 799
 800         /* Run on the final root fs (not in the initrd), to mount auxiliary partitions, and hook in rw
 801          * remount and growfs of the root partition */
 802
 803         r = block_get_whole_disk(devnum, &devnum);
 804         if (r < 0)
 805                 return log_debug_errno(r, "Failed to get whole block device for " DEVNUM_FORMAT_STR ": %m",
 806                                        DEVNUM_FORMAT_VAL(devnum));
 807
 808         r = devname_from_devnum(S_IFBLK, devnum, &devname);
 809         if (r < 0)
 810                 return log_debug_errno(r, "Failed to get device node of " DEVNUM_FORMAT_STR ": %m",
 811                                        DEVNUM_FORMAT_VAL(devnum));
 812
 813         /* Let's take a LOCK_SH lock on the block device, in case udevd is already running. If we don't take
 814          * the lock, udevd might end up issuing BLKRRPART in the middle, and we don't want that, since that
 815          * might remove all partitions while we are operating on them. */
 816         r = loop_device_open_from_path(devname, O_RDONLY, LOCK_SH, &loop);
 817         if (r < 0)
 818                 return log_debug_errno(r, "Failed to open %s: %m", devname);
 819
 820         r = dissect_loop_device(
 821                         loop,
 822                         /* verity= */ NULL,
 823                         /* mount_options= */ NULL,
 824                         arg_image_policy ?: &image_policy_host,
 825                         DISSECT_IMAGE_GPT_ONLY|
 826                         DISSECT_IMAGE_USR_NO_ROOT|
 827                         DISSECT_IMAGE_DISKSEQ_DEVNODE|
 828                         DISSECT_IMAGE_ALLOW_EMPTY,
 829                         /* NB! Unlike most other places where we dissect block devices we do not use
 830                          * DISSECT_IMAGE_ADD_PARTITION_DEVICES here: we want that the kernel finds the
 831                          * devices, and udev probes them before we mount them via .mount units much later
 832                          * on. And thus we also don't set DISSECT_IMAGE_PIN_PARTITION_DEVICES here, because
 833                          * we don't actually mount anything immediately. */
 834                         &m);
 835         if (r < 0) {
 836                 bool ok = r == -ENOPKG;
 837                 dissect_log_error(ok ? LOG_DEBUG : LOG_ERR, r, devname, NULL);
 838                 return ok ? 0 : r;
 839         }
 840
 841         if (m->partitions[PARTITION_SWAP].found)
 842                 RET_GATHER(r, add_partition_swap(m->partitions + PARTITION_SWAP));
 843
 844         RET_GATHER(r, process_loader_partitions(m->partitions + PARTITION_ESP, m->partitions + PARTITION_XBOOTLDR));
 845
 846         if (m->partitions[PARTITION_HOME].found)
 847                 RET_GATHER(r, add_partition_mount(PARTITION_HOME, m->partitions + PARTITION_HOME,
 848                                                   "home", "/home", "Home Partition"));
 849
 850         if (m->partitions[PARTITION_SRV].found)
 851                 RET_GATHER(r, add_partition_mount(PARTITION_SRV, m->partitions + PARTITION_SRV,
 852                                                   "srv", "/srv", "Server Data Partition"));
 853
 854         if (m->partitions[PARTITION_VAR].found)
 855                 RET_GATHER(r, add_partition_mount(PARTITION_VAR, m->partitions + PARTITION_VAR,
 856                                                   "var", "/var", "Variable Data Partition"));
 857
 858         if (m->partitions[PARTITION_TMP].found)
 859                 RET_GATHER(r, add_partition_mount(PARTITION_TMP, m->partitions + PARTITION_TMP,
 860                                                   "var-tmp", "/var/tmp", "Temporary Data Partition"));
 861
 862         if (m->partitions[PARTITION_ROOT].found)
 863                 RET_GATHER(r, add_partition_root_flags(m->partitions + PARTITION_ROOT));
 864
 865         return r;
 866 }
 867
 868 static int add_mounts(void) {
 869         dev_t devno;
 870         int r;
 871
 872         r = blockdev_get_root(LOG_ERR, &devno);
 873         if (r < 0)
 874                 return r;
 875         if (r == 0) {
 876                 log_debug("Skipping automatic GPT dissection logic, root file system not backed by a (single) whole block device.");
 877                 return 0;
 878         }
 879
 880         return enumerate_partitions(devno);
 881 }
 882
 883 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
 884         int r;
 885
 886         assert(key);
 887
 888         if (proc_cmdline_key_streq(key, "systemd.gpt_auto") ||
 889             proc_cmdline_key_streq(key, "rd.systemd.gpt_auto")) {
 890
 891                 r = value ? parse_boolean(value) : 1;
 892                 if (r < 0)
 893                         log_warning_errno(r, "Failed to parse gpt-auto switch \"%s\", ignoring: %m", value);
 894                 else
 895                         arg_enabled = r;
 896
 897         } else if (streq(key, "root")) {
 898
 899                 if (proc_cmdline_value_missing(key, value))
 900                         return 0;
 901
 902                 /* Disable root disk logic if there's a root= value
 903                  * specified (unless it happens to be "gpt-auto") */
 904
 905                 if (!streq(value, "gpt-auto")) {
 906                         arg_root_enabled = false;
 907                         log_debug("Disabling root partition auto-detection, root= is defined.");
 908                 }
 909
 910         } else if (streq(key, "roothash")) {
 911
 912                 if (proc_cmdline_value_missing(key, value))
 913                         return 0;
 914
 915                 /* Disable root disk logic if there's roothash= defined (i.e. verity enabled) */
 916
 917                 arg_root_enabled = false;
 918
 919         } else if (streq(key, "rootfstype")) {
 920
 921                 if (proc_cmdline_value_missing(key, value))
 922                         return 0;
 923
 924                 return free_and_strdup_warn(&arg_root_fstype, value);
 925
 926         } else if (streq(key, "rootflags")) {
 927
 928                 if (proc_cmdline_value_missing(key, value))
 929                         return 0;
 930
 931                 if (!strextend_with_separator(&arg_root_options, ",", value))
 932                         return log_oom();
 933
 934         } else if (streq(key, "rw") && !value)
 935                 arg_root_rw = true;
 936         else if (streq(key, "ro") && !value)
 937                 arg_root_rw = false;
 938         else if (proc_cmdline_key_streq(key, "systemd.image_policy"))
 939                 return parse_image_policy_argument(optarg, &arg_image_policy);
 940
 941         else if (streq(key, "systemd.swap")) {
 942
 943                 r = value ? parse_boolean(value) : 1;
 944                 if (r < 0)
 945                         log_warning_errno(r, "Failed to parse swap switch \"%s\", ignoring: %m", value);
 946                 else
 947                         arg_swap_enabled = r;
 948
 949                 if (!arg_swap_enabled)
 950                         log_debug("Disabling swap partitions auto-detection, systemd.swap=no is defined.");
 951
 952         }
 953
 954         return 0;
 955 }
 956
 957 static int run(const char *dest, const char *dest_early, const char *dest_late) {
 958         int r, k;
 959
 960         assert_se(arg_dest = dest_late);
 961
 962         if (detect_container() > 0) {
 963                 log_debug("In a container, exiting.");
 964                 return 0;
 965         }
 966
 967         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
 968         if (r < 0)
 969                 log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 970
 971         if (!arg_enabled) {
 972                 log_debug("Disabled, exiting.");
 973                 return 0;
 974         }
 975
 976         if (arg_root_enabled)
 977                 r = add_root_mount();
 978
 979         if (!in_initrd()) {
 980                 k = add_mounts();
 981                 if (r >= 0)
 982                         r = k;
 983         }
 984
 985         return r;
 986 }
 987
 988 DEFINE_MAIN_GENERATOR_FUNCTION(run);