src/fstab-generator/fstab-generator.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <errno.h>
   4 #include <stdio.h>
   5 #include <unistd.h>
   6
   7 #include "alloc-util.h"
   8 #include "fd-util.h"
   9 #include "fileio.h"
  10 #include "fs-util.h"
  11 #include "fstab-util.h"
  12 #include "generator.h"
  13 #include "log.h"
  14 #include "main-func.h"
  15 #include "mkdir.h"
  16 #include "mount-setup.h"
  17 #include "mount-util.h"
  18 #include "mountpoint-util.h"
  19 #include "parse-util.h"
  20 #include "path-util.h"
  21 #include "proc-cmdline.h"
  22 #include "special.h"
  23 #include "specifier.h"
  24 #include "stat-util.h"
  25 #include "string-util.h"
  26 #include "strv.h"
  27 #include "unit-name.h"
  28 #include "util.h"
  29 #include "virt.h"
  30 #include "volatile-util.h"
  31
  32 typedef enum MountPointFlags {
  33         MOUNT_NOAUTO    = 1 << 0,
  34         MOUNT_NOFAIL    = 1 << 1,
  35         MOUNT_AUTOMOUNT = 1 << 2,
  36         MOUNT_MAKEFS    = 1 << 3,
  37         MOUNT_GROWFS    = 1 << 4,
  38         MOUNT_RW_ONLY   = 1 << 5,
  39 } MountPointFlags;
  40
  41 static const char *arg_dest = NULL;
  42 static const char *arg_dest_late = NULL;
  43 static bool arg_fstab_enabled = true;
  44 static bool arg_swap_enabled = true;
  45 static char *arg_root_what = NULL;
  46 static char *arg_root_fstype = NULL;
  47 static char *arg_root_options = NULL;
  48 static char *arg_root_hash = NULL;
  49 static int arg_root_rw = -1;
  50 static char *arg_usr_what = NULL;
  51 static char *arg_usr_fstype = NULL;
  52 static char *arg_usr_options = NULL;
  53 static VolatileMode arg_volatile_mode = _VOLATILE_MODE_INVALID;
  54
  55 STATIC_DESTRUCTOR_REGISTER(arg_root_what, freep);
  56 STATIC_DESTRUCTOR_REGISTER(arg_root_fstype, freep);
  57 STATIC_DESTRUCTOR_REGISTER(arg_root_options, freep);
  58 STATIC_DESTRUCTOR_REGISTER(arg_root_hash, freep);
  59 STATIC_DESTRUCTOR_REGISTER(arg_usr_what, freep);
  60 STATIC_DESTRUCTOR_REGISTER(arg_usr_fstype, freep);
  61 STATIC_DESTRUCTOR_REGISTER(arg_usr_options, freep);
  62
  63 static int write_options(FILE *f, const char *options) {
  64         _cleanup_free_ char *o = NULL;
  65
  66         if (isempty(options))
  67                 return 0;
  68
  69         if (streq(options, "defaults"))
  70                 return 0;
  71
  72         o = specifier_escape(options);
  73         if (!o)
  74                 return log_oom();
  75
  76         fprintf(f, "Options=%s\n", o);
  77         return 1;
  78 }
  79
  80 static int write_what(FILE *f, const char *what) {
  81         _cleanup_free_ char *w = NULL;
  82
  83         w = specifier_escape(what);
  84         if (!w)
  85                 return log_oom();
  86
  87         fprintf(f, "What=%s\n", w);
  88         return 1;
  89 }
  90
  91 static int add_swap(
  92                 const char *what,
  93                 struct mntent *me,
  94                 MountPointFlags flags) {
  95
  96         _cleanup_free_ char *name = NULL;
  97         _cleanup_fclose_ FILE *f = NULL;
  98         int r;
  99
 100         assert(what);
 101         assert(me);
 102
 103         if (!arg_swap_enabled) {
 104                 log_info("Swap unit generation disabled on kernel command line, ignoring fstab swap entry for %s.", what);
 105                 return 0;
 106         }
 107
 108         if (access("/proc/swaps", F_OK) < 0) {
 109                 log_info("Swap not supported, ignoring fstab swap entry for %s.", what);
 110                 return 0;
 111         }
 112
 113         if (detect_container() > 0) {
 114                 log_info("Running in a container, ignoring fstab swap entry for %s.", what);
 115                 return 0;
 116         }
 117
 118         r = unit_name_from_path(what, ".swap", &name);
 119         if (r < 0)
 120                 return log_error_errno(r, "Failed to generate unit name: %m");
 121
 122         r = generator_open_unit_file(arg_dest, fstab_path(), name, &f);
 123         if (r < 0)
 124                 return r;
 125
 126         fprintf(f,
 127                 "[Unit]\n"
 128                 "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n"
 129                 "SourcePath=%s\n",
 130                 fstab_path());
 131
 132         r = generator_write_blockdev_dependency(f, what);
 133         if (r < 0)
 134                 return r;
 135
 136         fprintf(f,
 137                 "\n"
 138                 "[Swap]\n");
 139
 140         r = write_what(f, what);
 141         if (r < 0)
 142                 return r;
 143
 144         r = write_options(f, me->mnt_opts);
 145         if (r < 0)
 146                 return r;
 147
 148         r = fflush_and_check(f);
 149         if (r < 0)
 150                 return log_error_errno(r, "Failed to write unit file %s: %m", name);
 151
 152         /* use what as where, to have a nicer error message */
 153         r = generator_write_timeouts(arg_dest, what, what, me->mnt_opts, NULL);
 154         if (r < 0)
 155                 return r;
 156
 157         if (flags & MOUNT_MAKEFS) {
 158                 r = generator_hook_up_mkswap(arg_dest, what);
 159                 if (r < 0)
 160                         return r;
 161         }
 162
 163         if (flags & MOUNT_GROWFS)
 164                 /* TODO: swap devices must be wiped and recreated */
 165                 log_warning("%s: growing swap devices is currently unsupported.", what);
 166
 167         if (!(flags & MOUNT_NOAUTO)) {
 168                 r = generator_add_symlink(arg_dest, SPECIAL_SWAP_TARGET,
 169                                           (flags & MOUNT_NOFAIL) ? "wants" : "requires", name);
 170                 if (r < 0)
 171                         return r;
 172         }
 173
 174         return 0;
 175 }
 176
 177 static bool mount_is_network(struct mntent *me) {
 178         assert(me);
 179
 180         return fstab_test_option(me->mnt_opts, "_netdev\0") ||
 181                fstype_is_network(me->mnt_type);
 182 }
 183
 184 static bool mount_in_initrd(struct mntent *me) {
 185         assert(me);
 186
 187         return fstab_test_option(me->mnt_opts, "x-initrd.mount\0") ||
 188                streq(me->mnt_dir, "/usr");
 189 }
 190
 191 static int write_timeout(
 192                 FILE *f,
 193                 const char *where,
 194                 const char *opts,
 195                 const char *filter,
 196                 const char *variable) {
 197
 198         _cleanup_free_ char *timeout = NULL;
 199         usec_t u;
 200         int r;
 201
 202         r = fstab_filter_options(opts, filter, NULL, &timeout, NULL, NULL);
 203         if (r < 0)
 204                 return log_warning_errno(r, "Failed to parse options: %m");
 205         if (r == 0)
 206                 return 0;
 207
 208         r = parse_sec_fix_0(timeout, &u);
 209         if (r < 0) {
 210                 log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout);
 211                 return 0;
 212         }
 213
 214         fprintf(f, "%s=%s\n", variable, FORMAT_TIMESPAN(u, 0));
 215
 216         return 0;
 217 }
 218
 219 static int write_idle_timeout(FILE *f, const char *where, const char *opts) {
 220         return write_timeout(f, where, opts,
 221                              "x-systemd.idle-timeout\0", "TimeoutIdleSec");
 222 }
 223
 224 static int write_mount_timeout(FILE *f, const char *where, const char *opts) {
 225         return write_timeout(f, where, opts,
 226                              "x-systemd.mount-timeout\0", "TimeoutSec");
 227 }
 228
 229 static int write_dependency(
 230                 FILE *f,
 231                 const char *opts,
 232                 const char *filter,
 233                 const char *format) {
 234
 235         _cleanup_strv_free_ char **names = NULL, **units = NULL;
 236         _cleanup_free_ char *res = NULL;
 237         char **s;
 238         int r;
 239
 240         assert(f);
 241         assert(opts);
 242
 243         r = fstab_filter_options(opts, filter, NULL, NULL, &names, NULL);
 244         if (r < 0)
 245                 return log_warning_errno(r, "Failed to parse options: %m");
 246         if (r == 0)
 247                 return 0;
 248
 249         STRV_FOREACH(s, names) {
 250                 char *x;
 251
 252                 r = unit_name_mangle_with_suffix(*s, "as dependency", 0, ".mount", &x);
 253                 if (r < 0)
 254                         return log_error_errno(r, "Failed to generate unit name: %m");
 255
 256                 r = strv_consume(&units, x);
 257                 if (r < 0)
 258                         return log_oom();
 259         }
 260
 261         if (units) {
 262                 res = strv_join(units, " ");
 263                 if (!res)
 264                         return log_oom();
 265
 266                 DISABLE_WARNING_FORMAT_NONLITERAL;
 267                 fprintf(f, format, res);
 268                 REENABLE_WARNING;
 269         }
 270
 271         return 0;
 272 }
 273
 274 static int write_after(FILE *f, const char *opts) {
 275         return write_dependency(f, opts,
 276                                 "x-systemd.after\0", "After=%1$s\n");
 277 }
 278
 279 static int write_requires_after(FILE *f, const char *opts) {
 280         return write_dependency(f, opts,
 281                                 "x-systemd.requires\0", "After=%1$s\nRequires=%1$s\n");
 282 }
 283
 284 static int write_before(FILE *f, const char *opts) {
 285         return write_dependency(f, opts,
 286                                 "x-systemd.before\0", "Before=%1$s\n");
 287 }
 288
 289 static int write_requires_mounts_for(FILE *f, const char *opts) {
 290         _cleanup_strv_free_ char **paths = NULL, **paths_escaped = NULL;
 291         _cleanup_free_ char *res = NULL;
 292         int r;
 293
 294         assert(f);
 295         assert(opts);
 296
 297         r = fstab_filter_options(opts, "x-systemd.requires-mounts-for\0", NULL, NULL, &paths, NULL);
 298         if (r < 0)
 299                 return log_warning_errno(r, "Failed to parse options: %m");
 300         if (r == 0)
 301                 return 0;
 302
 303         r = specifier_escape_strv(paths, &paths_escaped);
 304         if (r < 0)
 305                 return log_error_errno(r, "Failed to escape paths: %m");
 306
 307         res = strv_join(paths_escaped, " ");
 308         if (!res)
 309                 return log_oom();
 310
 311         fprintf(f, "RequiresMountsFor=%s\n", res);
 312
 313         return 0;
 314 }
 315
 316 static int write_extra_dependencies(FILE *f, const char *opts) {
 317         int r;
 318
 319         assert(f);
 320
 321         if (opts) {
 322                 r = write_after(f, opts);
 323                 if (r < 0)
 324                         return r;
 325                 r = write_requires_after(f, opts);
 326                 if (r < 0)
 327                         return r;
 328                 r = write_before(f, opts);
 329                 if (r < 0)
 330                         return r;
 331                 r = write_requires_mounts_for(f, opts);
 332                 if (r < 0)
 333                         return r;
 334         }
 335
 336         return 0;
 337 }
 338
 339 static int add_mount(
 340                 const char *dest,
 341                 const char *what,
 342                 const char *where,
 343                 const char *original_where,
 344                 const char *fstype,
 345                 const char *opts,
 346                 int passno,
 347                 MountPointFlags flags,
 348                 const char *post,
 349                 const char *source) {
 350
 351         _cleanup_free_ char
 352                 *name = NULL,
 353                 *automount_name = NULL,
 354                 *filtered = NULL,
 355                 *where_escaped = NULL;
 356         _cleanup_strv_free_ char **wanted_by = NULL, **required_by = NULL;
 357         _cleanup_fclose_ FILE *f = NULL;
 358         int r;
 359
 360         assert(what);
 361         assert(where);
 362         assert(opts);
 363         assert(post);
 364         assert(source);
 365
 366         if (streq_ptr(fstype, "autofs"))
 367                 return 0;
 368
 369         if (!is_path(where)) {
 370                 log_warning("Mount point %s is not a valid path, ignoring.", where);
 371                 return 0;
 372         }
 373
 374         if (mount_point_is_api(where) ||
 375             mount_point_ignore(where))
 376                 return 0;
 377
 378         r = fstab_filter_options(opts, "x-systemd.wanted-by\0", NULL, NULL, &wanted_by, NULL);
 379         if (r < 0)
 380                 return r;
 381
 382         r = fstab_filter_options(opts, "x-systemd.required-by\0", NULL, NULL, &required_by, NULL);
 383         if (r < 0)
 384                 return r;
 385
 386         if (path_equal(where, "/")) {
 387                 if (flags & MOUNT_NOAUTO)
 388                         log_warning("Ignoring \"noauto\" option for root device");
 389                 if (flags & MOUNT_NOFAIL)
 390                         log_warning("Ignoring \"nofail\" option for root device");
 391                 if (flags & MOUNT_AUTOMOUNT)
 392                         log_warning("Ignoring \"automount\" option for root device");
 393                 if (!strv_isempty(wanted_by))
 394                         log_warning("Ignoring \"x-systemd.wanted-by=\" option for root device");
 395                 if (!strv_isempty(required_by))
 396                         log_warning("Ignoring \"x-systemd.required-by=\" option for root device");
 397
 398                 required_by = strv_free(required_by);
 399                 wanted_by = strv_free(wanted_by);
 400                 SET_FLAG(flags, MOUNT_NOAUTO | MOUNT_NOFAIL | MOUNT_AUTOMOUNT, false);
 401         }
 402
 403         r = unit_name_from_path(where, ".mount", &name);
 404         if (r < 0)
 405                 return log_error_errno(r, "Failed to generate unit name: %m");
 406
 407         r = generator_open_unit_file(dest, fstab_path(), name, &f);
 408         if (r < 0)
 409                 return r;
 410
 411         fprintf(f,
 412                 "[Unit]\n"
 413                 "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n"
 414                 "SourcePath=%s\n",
 415                 source);
 416
 417         if (STRPTR_IN_SET(fstype, "nfs", "nfs4") && !(flags & MOUNT_AUTOMOUNT) &&
 418             fstab_test_yes_no_option(opts, "bg\0" "fg\0")) {
 419                 /* The default retry timeout that mount.nfs uses for 'bg' mounts
 420                  * is 10000 minutes, where as it uses 2 minutes for 'fg' mounts.
 421                  * As we are making  'bg' mounts look like an 'fg' mount to
 422                  * mount.nfs (so systemd can manage the job-control aspects of 'bg'),
 423                  * we need to explicitly preserve that default, and also ensure
 424                  * the systemd mount-timeout doesn't interfere.
 425                  * By placing these options first, they can be overridden by
 426                  * settings in /etc/fstab. */
 427                 opts = strjoina("x-systemd.mount-timeout=infinity,retry=10000,nofail,", opts, ",fg");
 428                 SET_FLAG(flags, MOUNT_NOFAIL, true);
 429         }
 430
 431         r = write_extra_dependencies(f, opts);
 432         if (r < 0)
 433                 return r;
 434
 435         /* Order the mount unit we generate relative to the post unit, so that DefaultDependencies= on the
 436          * target unit won't affect us. */
 437         if (post && !FLAGS_SET(flags, MOUNT_AUTOMOUNT) && !FLAGS_SET(flags, MOUNT_NOAUTO) &&
 438             !FLAGS_SET(flags, MOUNT_NOFAIL))
 439                 fprintf(f, "Before=%s\n", post);
 440
 441         if (passno != 0) {
 442                 r = generator_write_fsck_deps(f, dest, what, where, fstype);
 443                 if (r < 0)
 444                         return r;
 445         }
 446
 447         r = generator_write_blockdev_dependency(f, what);
 448         if (r < 0)
 449                 return r;
 450
 451         fprintf(f,
 452                 "\n"
 453                 "[Mount]\n");
 454
 455         r = write_what(f, what);
 456         if (r < 0)
 457                 return r;
 458
 459         if (original_where)
 460                 fprintf(f, "# Canonicalized from %s\n", original_where);
 461
 462         where_escaped = specifier_escape(where);
 463         if (!where_escaped)
 464                 return log_oom();
 465         fprintf(f, "Where=%s\n", where_escaped);
 466
 467         if (!isempty(fstype) && !streq(fstype, "auto")) {
 468                 _cleanup_free_ char *t = NULL;
 469
 470                 t = specifier_escape(fstype);
 471                 if (!t)
 472                         return -ENOMEM;
 473
 474                 fprintf(f, "Type=%s\n", t);
 475         }
 476
 477         r = generator_write_timeouts(dest, what, where, opts, &filtered);
 478         if (r < 0)
 479                 return r;
 480
 481         r = generator_write_device_deps(dest, what, where, opts);
 482         if (r < 0)
 483                 return r;
 484
 485         r = write_mount_timeout(f, where, opts);
 486         if (r < 0)
 487                 return r;
 488
 489         r = write_options(f, filtered);
 490         if (r < 0)
 491                 return r;
 492
 493         if (flags & MOUNT_RW_ONLY)
 494                 fprintf(f, "ReadWriteOnly=yes\n");
 495
 496         r = fflush_and_check(f);
 497         if (r < 0)
 498                 return log_error_errno(r, "Failed to write unit file %s: %m", name);
 499
 500         if (flags & MOUNT_MAKEFS) {
 501                 r = generator_hook_up_mkfs(dest, what, where, fstype);
 502                 if (r < 0)
 503                         return r;
 504         }
 505
 506         if (flags & MOUNT_GROWFS) {
 507                 r = generator_hook_up_growfs(dest, where, post);
 508                 if (r < 0)
 509                         return r;
 510         }
 511
 512         if (!FLAGS_SET(flags, MOUNT_AUTOMOUNT)) {
 513                 if (!FLAGS_SET(flags, MOUNT_NOAUTO) && strv_isempty(wanted_by) && strv_isempty(required_by)) {
 514                         r = generator_add_symlink(dest, post,
 515                                                   (flags & MOUNT_NOFAIL) ? "wants" : "requires", name);
 516                         if (r < 0)
 517                                 return r;
 518                 } else {
 519                         char **s;
 520
 521                         STRV_FOREACH(s, wanted_by) {
 522                                 r = generator_add_symlink(dest, *s, "wants", name);
 523                                 if (r < 0)
 524                                         return r;
 525                         }
 526
 527                         STRV_FOREACH(s, required_by) {
 528                                 r = generator_add_symlink(dest, *s, "requires", name);
 529                                 if (r < 0)
 530                                         return r;
 531                         }
 532                 }
 533         } else {
 534                 r = unit_name_from_path(where, ".automount", &automount_name);
 535                 if (r < 0)
 536                         return log_error_errno(r, "Failed to generate unit name: %m");
 537
 538                 f = safe_fclose(f);
 539
 540                 r = generator_open_unit_file(dest, fstab_path(), automount_name, &f);
 541                 if (r < 0)
 542                         return r;
 543
 544                 fprintf(f,
 545                         "[Unit]\n"
 546                         "SourcePath=%s\n"
 547                         "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n",
 548                         source);
 549
 550                 fprintf(f,
 551                         "\n"
 552                         "[Automount]\n"
 553                         "Where=%s\n",
 554                         where_escaped);
 555
 556                 r = write_idle_timeout(f, where, opts);
 557                 if (r < 0)
 558                         return r;
 559
 560                 r = fflush_and_check(f);
 561                 if (r < 0)
 562                         return log_error_errno(r, "Failed to write unit file %s: %m", automount_name);
 563
 564                 r = generator_add_symlink(dest, post,
 565                                           (flags & MOUNT_NOFAIL) ? "wants" : "requires", automount_name);
 566                 if (r < 0)
 567                         return r;
 568         }
 569
 570         return 0;
 571 }
 572
 573 static int parse_fstab(bool initrd) {
 574         _cleanup_endmntent_ FILE *f = NULL;
 575         const char *fstab;
 576         struct mntent *me;
 577         int r = 0;
 578
 579         fstab = initrd ? "/sysroot/etc/fstab" : fstab_path();
 580         log_debug("Parsing %s...", fstab);
 581
 582         f = setmntent(fstab, "re");
 583         if (!f) {
 584                 if (errno == ENOENT)
 585                         return 0;
 586
 587                 return log_error_errno(errno, "Failed to open %s: %m", fstab);
 588         }
 589
 590         while ((me = getmntent(f))) {
 591                 _cleanup_free_ char *where = NULL, *what = NULL, *canonical_where = NULL;
 592                 bool makefs, growfs, noauto, nofail;
 593                 MountPointFlags flags;
 594                 int k;
 595
 596                 if (initrd && !mount_in_initrd(me))
 597                         continue;
 598
 599                 what = fstab_node_to_udev_node(me->mnt_fsname);
 600                 if (!what)
 601                         return log_oom();
 602
 603                 if (is_device_path(what) && path_is_read_only_fs("/sys") > 0) {
 604                         log_info("Running in a container, ignoring fstab device entry for %s.", what);
 605                         continue;
 606                 }
 607
 608                 where = strdup(me->mnt_dir);
 609                 if (!where)
 610                         return log_oom();
 611
 612                 if (is_path(where)) {
 613                         path_simplify(where);
 614
 615                         /* Follow symlinks here; see 5261ba901845c084de5a8fd06500ed09bfb0bd80 which makes sense for
 616                          * mount units, but causes problems since it historically worked to have symlinks in e.g.
 617                          * /etc/fstab. So we canonicalize here. Note that we use CHASE_NONEXISTENT to handle the case
 618                          * where a symlink refers to another mount target; this works assuming the sub-mountpoint
 619                          * target is the final directory. */
 620                         k = chase_symlinks(where, initrd ? "/sysroot" : NULL,
 621                                            CHASE_PREFIX_ROOT | CHASE_NONEXISTENT,
 622                                            &canonical_where, NULL);
 623                         if (k < 0) /* If we can't canonicalize we continue on as if it wasn't a symlink */
 624                                 log_debug_errno(k, "Failed to read symlink target for %s, ignoring: %m", where);
 625                         else if (streq(canonical_where, where)) /* If it was fully canonicalized, suppress the change */
 626                                 canonical_where = mfree(canonical_where);
 627                         else
 628                                 log_debug("Canonicalized what=%s where=%s to %s", what, where, canonical_where);
 629                 }
 630
 631                 makefs = fstab_test_option(me->mnt_opts, "x-systemd.makefs\0");
 632                 growfs = fstab_test_option(me->mnt_opts, "x-systemd.growfs\0");
 633                 noauto = fstab_test_yes_no_option(me->mnt_opts, "noauto\0" "auto\0");
 634                 nofail = fstab_test_yes_no_option(me->mnt_opts, "nofail\0" "fail\0");
 635
 636                 log_debug("Found entry what=%s where=%s type=%s makefs=%s growfs=%s noauto=%s nofail=%s",
 637                           what, where, me->mnt_type,
 638                           yes_no(makefs), yes_no(growfs),
 639                           yes_no(noauto), yes_no(nofail));
 640
 641                 flags = makefs * MOUNT_MAKEFS |
 642                         growfs * MOUNT_GROWFS |
 643                         noauto * MOUNT_NOAUTO |
 644                         nofail * MOUNT_NOFAIL;
 645
 646                 if (streq(me->mnt_type, "swap"))
 647                         k = add_swap(what, me, flags);
 648                 else {
 649                         bool rw_only, automount;
 650                         const char *post;
 651
 652                         rw_only = fstab_test_option(me->mnt_opts, "x-systemd.rw-only\0");
 653                         automount = fstab_test_option(me->mnt_opts,
 654                                                       "comment=systemd.automount\0"
 655                                                       "x-systemd.automount\0");
 656
 657                         flags |= rw_only * MOUNT_RW_ONLY |
 658                                  automount * MOUNT_AUTOMOUNT;
 659
 660                         if (initrd)
 661                                 post = SPECIAL_INITRD_FS_TARGET;
 662                         else if (mount_is_network(me))
 663                                 post = SPECIAL_REMOTE_FS_TARGET;
 664                         else
 665                                 post = SPECIAL_LOCAL_FS_TARGET;
 666
 667                         k = add_mount(arg_dest,
 668                                       what,
 669                                       canonical_where ?: where,
 670                                       canonical_where ? where: NULL,
 671                                       me->mnt_type,
 672                                       me->mnt_opts,
 673                                       me->mnt_passno,
 674                                       flags,
 675                                       post,
 676                                       fstab);
 677                 }
 678
 679                 if (r >= 0 && k < 0)
 680                         r = k;
 681         }
 682
 683         return r;
 684 }
 685
 686 static int add_sysroot_mount(void) {
 687         _cleanup_free_ char *what = NULL;
 688         const char *opts, *fstype;
 689         bool default_rw;
 690         int r;
 691
 692         if (isempty(arg_root_what)) {
 693                 log_debug("Could not find a root= entry on the kernel command line.");
 694                 return 0;
 695         }
 696
 697         if (streq(arg_root_what, "gpt-auto")) {
 698                 /* This is handled by the gpt-auto generator */
 699                 log_debug("Skipping root directory handling, as gpt-auto was requested.");
 700                 return 0;
 701         }
 702
 703         if (path_equal(arg_root_what, "/dev/nfs")) {
 704                 /* This is handled by the kernel or the initrd */
 705                 log_debug("Skipping root directory handling, as /dev/nfs was requested.");
 706                 return 0;
 707         }
 708
 709         if (streq(arg_root_what, "tmpfs")) {
 710                 /* If root=tmpfs is specified, then take this as shortcut for a writable tmpfs mount as root */
 711
 712                 what = strdup("rootfs"); /* just a pretty name, to show up in /proc/self/mountinfo */
 713                 if (!what)
 714                         return log_oom();
 715
 716                 fstype = arg_root_fstype ?: "tmpfs"; /* tmpfs, unless overridden */
 717
 718                 default_rw = true; /* writable, unless overridden */;
 719         } else {
 720
 721                 what = fstab_node_to_udev_node(arg_root_what);
 722                 if (!what)
 723                         return log_oom();
 724
 725                 fstype = arg_root_fstype; /* if not specified explicitly, don't default to anything here */
 726
 727                 default_rw = false; /* read-only, unless overridden */
 728         }
 729
 730         if (!arg_root_options)
 731                 opts = arg_root_rw > 0 || (arg_root_rw < 0 && default_rw) ? "rw" : "ro";
 732         else if (arg_root_rw >= 0 ||
 733                  !fstab_test_option(arg_root_options, "ro\0" "rw\0"))
 734                 opts = strjoina(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro");
 735         else
 736                 opts = arg_root_options;
 737
 738         log_debug("Found entry what=%s where=/sysroot type=%s opts=%s", what, strna(arg_root_fstype), strempty(opts));
 739
 740         if (is_device_path(what)) {
 741                 r = generator_write_initrd_root_device_deps(arg_dest, what);
 742                 if (r < 0)
 743                         return r;
 744         }
 745
 746         return add_mount(arg_dest,
 747                          what,
 748                          "/sysroot",
 749                          NULL,
 750                          fstype,
 751                          opts,
 752                          is_device_path(what) ? 1 : 0, /* passno */
 753                          0,                            /* makefs off, growfs off, noauto off, nofail off, automount off */
 754                          SPECIAL_INITRD_ROOT_FS_TARGET,
 755                          "/proc/cmdline");
 756 }
 757
 758 static int add_sysroot_usr_mount(void) {
 759         _cleanup_free_ char *what = NULL;
 760         const char *opts;
 761         int r;
 762
 763         /* Returns 0 if we didn't do anything, > 0 if we either generated a unit for the /usr/ mount, or we
 764          * know for sure something else did */
 765
 766         if (!arg_usr_what && !arg_usr_fstype && !arg_usr_options)
 767                 return 0;
 768
 769         if (arg_root_what && !arg_usr_what) {
 770                 /* Copy over the root device, in case the /usr mount just differs in a mount option (consider btrfs subvolumes) */
 771                 arg_usr_what = strdup(arg_root_what);
 772                 if (!arg_usr_what)
 773                         return log_oom();
 774         }
 775
 776         if (arg_root_fstype && !arg_usr_fstype) {
 777                 arg_usr_fstype = strdup(arg_root_fstype);
 778                 if (!arg_usr_fstype)
 779                         return log_oom();
 780         }
 781
 782         if (arg_root_options && !arg_usr_options) {
 783                 arg_usr_options = strdup(arg_root_options);
 784                 if (!arg_usr_options)
 785                         return log_oom();
 786         }
 787
 788         if (isempty(arg_usr_what)) {
 789                 log_debug("Could not find a usr= entry on the kernel command line.");
 790                 return 0;
 791         }
 792
 793         if (streq(arg_usr_what, "gpt-auto")) {
 794                 /* This is handled by the gpt-auto generator */
 795                 log_debug("Skipping /usr/ directory handling, as gpt-auto was requested.");
 796                 return 1; /* systemd-gpt-auto-generator will generate a unit for this, hence report that a
 797                            * unit file is being created for the host /usr/ mount. */
 798         }
 799
 800         if (path_equal(arg_usr_what, "/dev/nfs")) {
 801                 /* This is handled by the initrd (if at all supported, that is) */
 802                 log_debug("Skipping /usr/ directory handling, as /dev/nfs was requested.");
 803                 return 1; /* As above, report that NFS code will create the unit */
 804         }
 805
 806         what = fstab_node_to_udev_node(arg_usr_what);
 807         if (!what)
 808                 return log_oom();
 809
 810         if (!arg_usr_options)
 811                 opts = arg_root_rw > 0 ? "rw" : "ro";
 812         else if (!fstab_test_option(arg_usr_options, "ro\0" "rw\0"))
 813                 opts = strjoina(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro");
 814         else
 815                 opts = arg_usr_options;
 816
 817         /* When mounting /usr from the initrd, we add an extra level of indirection: we first mount the /usr/
 818          * partition to /sysusr/usr/, and then afterwards bind mount that to /sysroot/usr/. We do this so
 819          * that we can cover for systems that initially only have a /usr/ around and where the root fs needs
 820          * to be synthesized, based on configuration included in /usr/, e.g. systemd-repart. Software like
 821          * this should order itself after initrd-usr-fs.target and before initrd-fs.target; and it should
 822          * look into both /sysusr/ and /sysroot/ for the configuration data to apply. */
 823
 824         log_debug("Found entry what=%s where=/sysusr/usr type=%s opts=%s", what, strna(arg_usr_fstype), strempty(opts));
 825
 826         r = add_mount(arg_dest,
 827                       what,
 828                       "/sysusr/usr",
 829                       NULL,
 830                       arg_usr_fstype,
 831                       opts,
 832                       is_device_path(what) ? 1 : 0, /* passno */
 833                       0,
 834                       SPECIAL_INITRD_USR_FS_TARGET,
 835                       "/proc/cmdline");
 836         if (r < 0)
 837                 return r;
 838
 839         log_debug("Synthesizing entry what=/sysusr/usr where=/sysrootr/usr opts=bind");
 840
 841         r = add_mount(arg_dest,
 842                       "/sysusr/usr",
 843                       "/sysroot/usr",
 844                       NULL,
 845                       NULL,
 846                       "bind",
 847                       0,
 848                       0,
 849                       SPECIAL_INITRD_FS_TARGET,
 850                       "/proc/cmdline");
 851         if (r < 0)
 852                 return r;
 853
 854         return 1;
 855 }
 856
 857 static int add_sysroot_usr_mount_or_fallback(void) {
 858         int r;
 859
 860         r = add_sysroot_usr_mount();
 861         if (r != 0)
 862                 return r;
 863
 864         /* OK, so we didn't write anything out for /sysusr/usr/ nor /sysroot/usr/. In this case, let's make
 865          * sure that initrd-usr-fs.target is at least ordered after sysroot.mount so that services that order
 866          * themselves get the guarantee that /usr/ is definitely mounted somewhere. */
 867
 868         return generator_add_symlink(
 869                         arg_dest,
 870                         SPECIAL_INITRD_USR_FS_TARGET,
 871                         "requires",
 872                         "sysroot.mount");
 873 }
 874
 875 static int add_volatile_root(void) {
 876
 877         /* Let's add in systemd-remount-volatile.service which will remount the root device to tmpfs if this is
 878          * requested (or as an overlayfs), leaving only /usr from the root mount inside. */
 879
 880         if (!IN_SET(arg_volatile_mode, VOLATILE_YES, VOLATILE_OVERLAY))
 881                 return 0;
 882
 883         return generator_add_symlink(arg_dest, SPECIAL_INITRD_ROOT_FS_TARGET, "requires",
 884                                      SYSTEM_DATA_UNIT_DIR "/" SPECIAL_VOLATILE_ROOT_SERVICE);
 885 }
 886
 887 static int add_volatile_var(void) {
 888
 889         if (arg_volatile_mode != VOLATILE_STATE)
 890                 return 0;
 891
 892         /* If requested, mount /var as tmpfs, but do so only if there's nothing else defined for this. */
 893
 894         return add_mount(arg_dest_late,
 895                          "tmpfs",
 896                          "/var",
 897                          NULL,
 898                          "tmpfs",
 899                          "mode=0755" TMPFS_LIMITS_VAR,
 900                          0,
 901                          0,
 902                          SPECIAL_LOCAL_FS_TARGET,
 903                          "/proc/cmdline");
 904 }
 905
 906 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
 907         int r;
 908
 909         /* root=, usr=, usrfstype= and roofstype= may occur more than once, the last
 910          * instance should take precedence.  In the case of multiple rootflags=
 911          * or usrflags= the arguments should be concatenated */
 912
 913         if (STR_IN_SET(key, "fstab", "rd.fstab")) {
 914
 915                 r = value ? parse_boolean(value) : 1;
 916                 if (r < 0)
 917                         log_warning("Failed to parse fstab switch %s. Ignoring.", value);
 918                 else
 919                         arg_fstab_enabled = r;
 920
 921         } else if (streq(key, "root")) {
 922
 923                 if (proc_cmdline_value_missing(key, value))
 924                         return 0;
 925
 926                 return free_and_strdup_warn(&arg_root_what, value);
 927
 928         } else if (streq(key, "rootfstype")) {
 929
 930                 if (proc_cmdline_value_missing(key, value))
 931                         return 0;
 932
 933                 return free_and_strdup_warn(&arg_root_fstype, value);
 934
 935         } else if (streq(key, "rootflags")) {
 936
 937                 if (proc_cmdline_value_missing(key, value))
 938                         return 0;
 939
 940                 if (!strextend_with_separator(&arg_root_options, ",", value))
 941                         return log_oom();
 942
 943         } else if (streq(key, "roothash")) {
 944
 945                 if (proc_cmdline_value_missing(key, value))
 946                         return 0;
 947
 948                 return free_and_strdup_warn(&arg_root_hash, value);
 949
 950         } else if (streq(key, "mount.usr")) {
 951
 952                 if (proc_cmdline_value_missing(key, value))
 953                         return 0;
 954
 955                 return free_and_strdup_warn(&arg_usr_what, value);
 956
 957         } else if (streq(key, "mount.usrfstype")) {
 958
 959                 if (proc_cmdline_value_missing(key, value))
 960                         return 0;
 961
 962                 return free_and_strdup_warn(&arg_usr_fstype, value);
 963
 964         } else if (streq(key, "mount.usrflags")) {
 965
 966                 if (proc_cmdline_value_missing(key, value))
 967                         return 0;
 968
 969                 if (!strextend_with_separator(&arg_usr_options, ",", value))
 970                         return log_oom();
 971
 972         } else if (streq(key, "rw") && !value)
 973                 arg_root_rw = true;
 974         else if (streq(key, "ro") && !value)
 975                 arg_root_rw = false;
 976         else if (streq(key, "systemd.volatile")) {
 977                 VolatileMode m;
 978
 979                 if (value) {
 980                         m = volatile_mode_from_string(value);
 981                         if (m < 0)
 982                                 log_warning_errno(m, "Failed to parse systemd.volatile= argument: %s", value);
 983                         else
 984                                 arg_volatile_mode = m;
 985                 } else
 986                         arg_volatile_mode = VOLATILE_YES;
 987
 988         } else if (streq(key, "systemd.swap")) {
 989
 990                 r = value ? parse_boolean(value) : 1;
 991                 if (r < 0)
 992                         log_warning("Failed to parse systemd.swap switch %s. Ignoring.", value);
 993                 else
 994                         arg_swap_enabled = r;
 995         }
 996
 997         return 0;
 998 }
 999
1000 static int determine_root(void) {
1001         /* If we have a root hash but no root device then Verity is used, and we use the "root" DM device as root. */
1002
1003         if (arg_root_what)
1004                 return 0;
1005
1006         if (!arg_root_hash)
1007                 return 0;
1008
1009         arg_root_what = strdup("/dev/mapper/root");
1010         if (!arg_root_what)
1011                 return log_oom();
1012
1013         log_info("Using verity root device %s.", arg_root_what);
1014
1015         return 1;
1016 }
1017
1018 static int run(const char *dest, const char *dest_early, const char *dest_late) {
1019         int r, r2 = 0, r3 = 0;
1020
1021         assert_se(arg_dest = dest);
1022         assert_se(arg_dest_late = dest_late);
1023
1024         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
1025         if (r < 0)
1026                 log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
1027
1028         (void) determine_root();
1029
1030         /* Always honour root= and usr= in the kernel command line if we are in an initrd */
1031         if (in_initrd()) {
1032                 r = add_sysroot_mount();
1033
1034                 r2 = add_sysroot_usr_mount_or_fallback();
1035
1036                 r3 = add_volatile_root();
1037         } else
1038                 r = add_volatile_var();
1039
1040         /* Honour /etc/fstab only when that's enabled */
1041         if (arg_fstab_enabled) {
1042                 /* Parse the local /etc/fstab, possibly from the initrd */
1043                 r2 = parse_fstab(false);
1044
1045                 /* If running in the initrd also parse the /etc/fstab from the host */
1046                 if (in_initrd())
1047                         r3 = parse_fstab(true);
1048                 else
1049                         r3 = generator_enable_remount_fs_service(arg_dest);
1050         }
1051
1052         return r < 0 ? r : r2 < 0 ? r2 : r3;
1053 }
1054
1055 DEFINE_MAIN_GENERATOR_FUNCTION(run);