src/shared/dissect-image.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #if HAVE_VALGRIND_MEMCHECK_H
   4 #include <valgrind/memcheck.h>
   5 #endif
   6
   7 #include <linux/dm-ioctl.h>
   8 #include <linux/loop.h>
   9 #include <sys/mount.h>
  10 #include <sys/prctl.h>
  11 #include <sys/wait.h>
  12
  13 #include "sd-device.h"
  14 #include "sd-id128.h"
  15
  16 #include "architecture.h"
  17 #include "ask-password-api.h"
  18 #include "blkid-util.h"
  19 #include "blockdev-util.h"
  20 #include "copy.h"
  21 #include "crypt-util.h"
  22 #include "def.h"
  23 #include "device-nodes.h"
  24 #include "device-util.h"
  25 #include "dissect-image.h"
  26 #include "dm-util.h"
  27 #include "env-file.h"
  28 #include "fd-util.h"
  29 #include "fileio.h"
  30 #include "fs-util.h"
  31 #include "gpt.h"
  32 #include "hexdecoct.h"
  33 #include "hostname-util.h"
  34 #include "id128-util.h"
  35 #include "mount-util.h"
  36 #include "mountpoint-util.h"
  37 #include "nulstr-util.h"
  38 #include "os-util.h"
  39 #include "path-util.h"
  40 #include "process-util.h"
  41 #include "raw-clone.h"
  42 #include "signal-util.h"
  43 #include "stat-util.h"
  44 #include "stdio-util.h"
  45 #include "string-table.h"
  46 #include "string-util.h"
  47 #include "strv.h"
  48 #include "tmpfile-util.h"
  49 #include "udev-util.h"
  50 #include "user-util.h"
  51 #include "xattr-util.h"
  52
  53 int probe_filesystem(const char *node, char **ret_fstype) {
  54         /* Try to find device content type and return it in *ret_fstype. If nothing is found,
  55          * 0/NULL will be returned. -EUCLEAN will be returned for ambiguous results, and an
  56          * different error otherwise. */
  57
  58 #if HAVE_BLKID
  59         _cleanup_(blkid_free_probep) blkid_probe b = NULL;
  60         const char *fstype;
  61         int r;
  62
  63         errno = 0;
  64         b = blkid_new_probe_from_filename(node);
  65         if (!b)
  66                 return errno_or_else(ENOMEM);
  67
  68         blkid_probe_enable_superblocks(b, 1);
  69         blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE);
  70
  71         errno = 0;
  72         r = blkid_do_safeprobe(b);
  73         if (r == 1) {
  74                 log_debug("No type detected on partition %s", node);
  75                 goto not_found;
  76         }
  77         if (r == -2) {
  78                 log_debug("Results ambiguous for partition %s", node);
  79                 return -EUCLEAN;
  80         }
  81         if (r != 0)
  82                 return errno_or_else(EIO);
  83
  84         (void) blkid_probe_lookup_value(b, "TYPE", &fstype, NULL);
  85
  86         if (fstype) {
  87                 char *t;
  88
  89                 t = strdup(fstype);
  90                 if (!t)
  91                         return -ENOMEM;
  92
  93                 *ret_fstype = t;
  94                 return 1;
  95         }
  96
  97 not_found:
  98         *ret_fstype = NULL;
  99         return 0;
 100 #else
 101         return -EOPNOTSUPP;
 102 #endif
 103 }
 104
 105 #if HAVE_BLKID
 106 /* Detect RPMB and Boot partitions, which are not listed by blkid.
 107  * See https://github.com/systemd/systemd/issues/5806. */
 108 static bool device_is_mmc_special_partition(sd_device *d) {
 109         const char *sysname;
 110
 111         assert(d);
 112
 113         if (sd_device_get_sysname(d, &sysname) < 0)
 114                 return false;
 115
 116         return startswith(sysname, "mmcblk") &&
 117                 (endswith(sysname, "rpmb") || endswith(sysname, "boot0") || endswith(sysname, "boot1"));
 118 }
 119
 120 static bool device_is_block(sd_device *d) {
 121         const char *ss;
 122
 123         assert(d);
 124
 125         if (sd_device_get_subsystem(d, &ss) < 0)
 126                 return false;
 127
 128         return streq(ss, "block");
 129 }
 130
 131 static int enumerator_for_parent(sd_device *d, sd_device_enumerator **ret) {
 132         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 133         int r;
 134
 135         assert(d);
 136         assert(ret);
 137
 138         r = sd_device_enumerator_new(&e);
 139         if (r < 0)
 140                 return r;
 141
 142         r = sd_device_enumerator_allow_uninitialized(e);
 143         if (r < 0)
 144                 return r;
 145
 146         r = sd_device_enumerator_add_match_parent(e, d);
 147         if (r < 0)
 148                 return r;
 149
 150         *ret = TAKE_PTR(e);
 151         return 0;
 152 }
 153
 154 /* how many times to wait for the device nodes to appear */
 155 #define N_DEVICE_NODE_LIST_ATTEMPTS 10
 156
 157 static int wait_for_partitions_to_appear(
 158                 int fd,
 159                 sd_device *d,
 160                 unsigned num_partitions,
 161                 DissectImageFlags flags,
 162                 sd_device_enumerator **ret_enumerator) {
 163
 164         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 165         sd_device *q;
 166         unsigned n;
 167         int r;
 168
 169         assert(fd >= 0);
 170         assert(d);
 171         assert(ret_enumerator);
 172
 173         r = enumerator_for_parent(d, &e);
 174         if (r < 0)
 175                 return r;
 176
 177         /* Count the partitions enumerated by the kernel */
 178         n = 0;
 179         FOREACH_DEVICE(e, q) {
 180                 if (sd_device_get_devnum(q, NULL) < 0)
 181                         continue;
 182                 if (!device_is_block(q))
 183                         continue;
 184                 if (device_is_mmc_special_partition(q))
 185                         continue;
 186
 187                 if (!FLAGS_SET(flags, DISSECT_IMAGE_NO_UDEV)) {
 188                         r = device_wait_for_initialization(q, "block", USEC_INFINITY, NULL);
 189                         if (r < 0)
 190                                 return r;
 191                 }
 192
 193                 n++;
 194         }
 195
 196         if (n == num_partitions + 1) {
 197                 *ret_enumerator = TAKE_PTR(e);
 198                 return 0; /* success! */
 199         }
 200         if (n > num_partitions + 1)
 201                 return log_debug_errno(SYNTHETIC_ERRNO(EIO),
 202                                        "blkid and kernel partition lists do not match.");
 203
 204         /* The kernel has probed fewer partitions than blkid? Maybe the kernel prober is still running or it
 205          * got EBUSY because udev already opened the device. Let's reprobe the device, which is a synchronous
 206          * call that waits until probing is complete. */
 207
 208         for (unsigned j = 0; ; j++) {
 209                 if (j++ > 20)
 210                         return -EBUSY;
 211
 212                 if (ioctl(fd, BLKRRPART, 0) >= 0)
 213                         break;
 214                 r = -errno;
 215                 if (r == -EINVAL) {
 216                         struct loop_info64 info;
 217
 218                         /* If we are running on a loop device that has partition scanning off, return
 219                          * an explicit recognizable error about this, so that callers can generate a
 220                          * proper message explaining the situation. */
 221
 222                         if (ioctl(fd, LOOP_GET_STATUS64, &info) >= 0) {
 223 #if HAVE_VALGRIND_MEMCHECK_H
 224                                 /* Valgrind currently doesn't know LOOP_GET_STATUS64. Remove this once it does */
 225                                 VALGRIND_MAKE_MEM_DEFINED(&info, sizeof(info));
 226 #endif
 227
 228                                 if ((info.lo_flags & LO_FLAGS_PARTSCAN) == 0)
 229                                         return log_debug_errno(EPROTONOSUPPORT,
 230                                                                "Device is a loop device and partition scanning is off!");
 231                         }
 232                 }
 233                 if (r != -EBUSY)
 234                         return r;
 235
 236                 /* If something else has the device open, such as an udev rule, the ioctl will return
 237                  * EBUSY. Since there's no way to wait until it isn't busy anymore, let's just wait a bit,
 238                  * and try again.
 239                  *
 240                  * This is really something they should fix in the kernel! */
 241                 (void) usleep(50 * USEC_PER_MSEC);
 242
 243         }
 244
 245         return -EAGAIN; /* no success yet, try again */
 246 }
 247
 248 static int loop_wait_for_partitions_to_appear(
 249                 int fd,
 250                 sd_device *d,
 251                 unsigned num_partitions,
 252                 DissectImageFlags flags,
 253                 sd_device_enumerator **ret_enumerator) {
 254         _cleanup_(sd_device_unrefp) sd_device *device = NULL;
 255         int r;
 256
 257         assert(fd >= 0);
 258         assert(d);
 259         assert(ret_enumerator);
 260
 261         log_debug("Waiting for device (parent + %d partitions) to appear...", num_partitions);
 262
 263         if (!FLAGS_SET(flags, DISSECT_IMAGE_NO_UDEV)) {
 264                 r = device_wait_for_initialization(d, "block", USEC_INFINITY, &device);
 265                 if (r < 0)
 266                         return r;
 267         } else
 268                 device = sd_device_ref(d);
 269
 270         for (unsigned i = 0; i < N_DEVICE_NODE_LIST_ATTEMPTS; i++) {
 271                 r = wait_for_partitions_to_appear(fd, device, num_partitions, flags, ret_enumerator);
 272                 if (r != -EAGAIN)
 273                         return r;
 274         }
 275
 276         return log_debug_errno(SYNTHETIC_ERRNO(ENXIO),
 277                                "Kernel partitions dit not appear within %d attempts",
 278                                N_DEVICE_NODE_LIST_ATTEMPTS);
 279 }
 280
 281 #endif
 282
 283 int dissect_image(
 284                 int fd,
 285                 const void *root_hash,
 286                 size_t root_hash_size,
 287                 DissectImageFlags flags,
 288                 DissectedImage **ret) {
 289
 290 #if HAVE_BLKID
 291         sd_id128_t root_uuid = SD_ID128_NULL, verity_uuid = SD_ID128_NULL;
 292         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 293         bool is_gpt, is_mbr, generic_rw, multiple_generic = false;
 294         _cleanup_(sd_device_unrefp) sd_device *d = NULL;
 295         _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
 296         _cleanup_(blkid_free_probep) blkid_probe b = NULL;
 297         _cleanup_free_ char *generic_node = NULL;
 298         sd_id128_t generic_uuid = SD_ID128_NULL;
 299         const char *pttype = NULL;
 300         blkid_partlist pl;
 301         int r, generic_nr;
 302         struct stat st;
 303         sd_device *q;
 304         unsigned i;
 305
 306         assert(fd >= 0);
 307         assert(ret);
 308         assert(root_hash || root_hash_size == 0);
 309
 310         /* Probes a disk image, and returns information about what it found in *ret.
 311          *
 312          * Returns -ENOPKG if no suitable partition table or file system could be found.
 313          * Returns -EADDRNOTAVAIL if a root hash was specified but no matching root/verity partitions found. */
 314
 315         if (root_hash) {
 316                 /* If a root hash is supplied, then we use the root partition that has a UUID that match the first
 317                  * 128bit of the root hash. And we use the verity partition that has a UUID that match the final
 318                  * 128bit. */
 319
 320                 if (root_hash_size < sizeof(sd_id128_t))
 321                         return -EINVAL;
 322
 323                 memcpy(&root_uuid, root_hash, sizeof(sd_id128_t));
 324                 memcpy(&verity_uuid, (const uint8_t*) root_hash + root_hash_size - sizeof(sd_id128_t), sizeof(sd_id128_t));
 325
 326                 if (sd_id128_is_null(root_uuid))
 327                         return -EINVAL;
 328                 if (sd_id128_is_null(verity_uuid))
 329                         return -EINVAL;
 330         }
 331
 332         if (fstat(fd, &st) < 0)
 333                 return -errno;
 334
 335         if (!S_ISBLK(st.st_mode))
 336                 return -ENOTBLK;
 337
 338         b = blkid_new_probe();
 339         if (!b)
 340                 return -ENOMEM;
 341
 342         errno = 0;
 343         r = blkid_probe_set_device(b, fd, 0, 0);
 344         if (r != 0)
 345                 return errno_or_else(ENOMEM);
 346
 347         if ((flags & DISSECT_IMAGE_GPT_ONLY) == 0) {
 348                 /* Look for file system superblocks, unless we only shall look for GPT partition tables */
 349                 blkid_probe_enable_superblocks(b, 1);
 350                 blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE|BLKID_SUBLKS_USAGE);
 351         }
 352
 353         blkid_probe_enable_partitions(b, 1);
 354         blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS);
 355
 356         errno = 0;
 357         r = blkid_do_safeprobe(b);
 358         if (IN_SET(r, -2, 1))
 359                 return log_debug_errno(SYNTHETIC_ERRNO(ENOPKG), "Failed to identify any partition table.");
 360         if (r != 0)
 361                 return errno_or_else(EIO);
 362
 363         m = new0(DissectedImage, 1);
 364         if (!m)
 365                 return -ENOMEM;
 366
 367         r = sd_device_new_from_devnum(&d, 'b', st.st_rdev);
 368         if (r < 0)
 369                 return r;
 370
 371         if (!(flags & DISSECT_IMAGE_GPT_ONLY) &&
 372             (flags & DISSECT_IMAGE_REQUIRE_ROOT)) {
 373                 const char *usage = NULL;
 374
 375                 (void) blkid_probe_lookup_value(b, "USAGE", &usage, NULL);
 376                 if (STRPTR_IN_SET(usage, "filesystem", "crypto")) {
 377                         _cleanup_free_ char *t = NULL, *n = NULL;
 378                         const char *fstype = NULL;
 379
 380                         /* OK, we have found a file system, that's our root partition then. */
 381                         (void) blkid_probe_lookup_value(b, "TYPE", &fstype, NULL);
 382
 383                         if (fstype) {
 384                                 t = strdup(fstype);
 385                                 if (!t)
 386                                         return -ENOMEM;
 387                         }
 388
 389                         r = device_path_make_major_minor(st.st_mode, st.st_rdev, &n);
 390                         if (r < 0)
 391                                 return r;
 392
 393                         m->partitions[PARTITION_ROOT] = (DissectedPartition) {
 394                                 .found = true,
 395                                 .rw = true,
 396                                 .partno = -1,
 397                                 .architecture = _ARCHITECTURE_INVALID,
 398                                 .fstype = TAKE_PTR(t),
 399                                 .node = TAKE_PTR(n),
 400                         };
 401
 402                         m->encrypted = streq_ptr(fstype, "crypto_LUKS");
 403
 404                         r = loop_wait_for_partitions_to_appear(fd, d, 0, flags, &e);
 405                         if (r < 0)
 406                                 return r;
 407
 408                         *ret = TAKE_PTR(m);
 409
 410                         return 0;
 411                 }
 412         }
 413
 414         (void) blkid_probe_lookup_value(b, "PTTYPE", &pttype, NULL);
 415         if (!pttype)
 416                 return -ENOPKG;
 417
 418         is_gpt = streq_ptr(pttype, "gpt");
 419         is_mbr = streq_ptr(pttype, "dos");
 420
 421         if (!is_gpt && ((flags & DISSECT_IMAGE_GPT_ONLY) || !is_mbr))
 422                 return -ENOPKG;
 423
 424         errno = 0;
 425         pl = blkid_probe_get_partitions(b);
 426         if (!pl)
 427                 return errno_or_else(ENOMEM);
 428
 429         r = loop_wait_for_partitions_to_appear(fd, d, blkid_partlist_numof_partitions(pl), flags, &e);
 430         if (r < 0)
 431                 return r;
 432
 433         FOREACH_DEVICE(e, q) {
 434                 unsigned long long pflags;
 435                 blkid_partition pp;
 436                 const char *node;
 437                 dev_t qn;
 438                 int nr;
 439
 440                 r = sd_device_get_devnum(q, &qn);
 441                 if (r < 0)
 442                         continue;
 443
 444                 if (st.st_rdev == qn)
 445                         continue;
 446
 447                 if (!device_is_block(q))
 448                         continue;
 449
 450                 if (device_is_mmc_special_partition(q))
 451                         continue;
 452
 453                 r = sd_device_get_devname(q, &node);
 454                 if (r < 0)
 455                         continue;
 456
 457                 pp = blkid_partlist_devno_to_partition(pl, qn);
 458                 if (!pp)
 459                         continue;
 460
 461                 pflags = blkid_partition_get_flags(pp);
 462
 463                 nr = blkid_partition_get_partno(pp);
 464                 if (nr < 0)
 465                         continue;
 466
 467                 if (is_gpt) {
 468                         int designator = _PARTITION_DESIGNATOR_INVALID, architecture = _ARCHITECTURE_INVALID;
 469                         const char *stype, *sid, *fstype = NULL;
 470                         sd_id128_t type_id, id;
 471                         bool rw = true;
 472
 473                         sid = blkid_partition_get_uuid(pp);
 474                         if (!sid)
 475                                 continue;
 476                         if (sd_id128_from_string(sid, &id) < 0)
 477                                 continue;
 478
 479                         stype = blkid_partition_get_type_string(pp);
 480                         if (!stype)
 481                                 continue;
 482                         if (sd_id128_from_string(stype, &type_id) < 0)
 483                                 continue;
 484
 485                         if (sd_id128_equal(type_id, GPT_HOME)) {
 486
 487                                 if (pflags & GPT_FLAG_NO_AUTO)
 488                                         continue;
 489
 490                                 designator = PARTITION_HOME;
 491                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 492                         } else if (sd_id128_equal(type_id, GPT_SRV)) {
 493
 494                                 if (pflags & GPT_FLAG_NO_AUTO)
 495                                         continue;
 496
 497                                 designator = PARTITION_SRV;
 498                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 499                         } else if (sd_id128_equal(type_id, GPT_ESP)) {
 500
 501                                 /* Note that we don't check the GPT_FLAG_NO_AUTO flag for the ESP, as it is not defined
 502                                  * there. We instead check the GPT_FLAG_NO_BLOCK_IO_PROTOCOL, as recommended by the
 503                                  * UEFI spec (See "12.3.3 Number and Location of System Partitions"). */
 504
 505                                 if (pflags & GPT_FLAG_NO_BLOCK_IO_PROTOCOL)
 506                                         continue;
 507
 508                                 designator = PARTITION_ESP;
 509                                 fstype = "vfat";
 510
 511                         } else if (sd_id128_equal(type_id, GPT_XBOOTLDR)) {
 512
 513                                 if (pflags & GPT_FLAG_NO_AUTO)
 514                                         continue;
 515
 516                                 designator = PARTITION_XBOOTLDR;
 517                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 518                         }
 519 #ifdef GPT_ROOT_NATIVE
 520                         else if (sd_id128_equal(type_id, GPT_ROOT_NATIVE)) {
 521
 522                                 if (pflags & GPT_FLAG_NO_AUTO)
 523                                         continue;
 524
 525                                 /* If a root ID is specified, ignore everything but the root id */
 526                                 if (!sd_id128_is_null(root_uuid) && !sd_id128_equal(root_uuid, id))
 527                                         continue;
 528
 529                                 designator = PARTITION_ROOT;
 530                                 architecture = native_architecture();
 531                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 532                         } else if (sd_id128_equal(type_id, GPT_ROOT_NATIVE_VERITY)) {
 533
 534                                 if (pflags & GPT_FLAG_NO_AUTO)
 535                                         continue;
 536
 537                                 m->can_verity = true;
 538
 539                                 /* Ignore verity unless a root hash is specified */
 540                                 if (sd_id128_is_null(verity_uuid) || !sd_id128_equal(verity_uuid, id))
 541                                         continue;
 542
 543                                 designator = PARTITION_ROOT_VERITY;
 544                                 fstype = "DM_verity_hash";
 545                                 architecture = native_architecture();
 546                                 rw = false;
 547                         }
 548 #endif
 549 #ifdef GPT_ROOT_SECONDARY
 550                         else if (sd_id128_equal(type_id, GPT_ROOT_SECONDARY)) {
 551
 552                                 if (pflags & GPT_FLAG_NO_AUTO)
 553                                         continue;
 554
 555                                 /* If a root ID is specified, ignore everything but the root id */
 556                                 if (!sd_id128_is_null(root_uuid) && !sd_id128_equal(root_uuid, id))
 557                                         continue;
 558
 559                                 designator = PARTITION_ROOT_SECONDARY;
 560                                 architecture = SECONDARY_ARCHITECTURE;
 561                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 562                         } else if (sd_id128_equal(type_id, GPT_ROOT_SECONDARY_VERITY)) {
 563
 564                                 if (pflags & GPT_FLAG_NO_AUTO)
 565                                         continue;
 566
 567                                 m->can_verity = true;
 568
 569                                 /* Ignore verity unless root has is specified */
 570                                 if (sd_id128_is_null(verity_uuid) || !sd_id128_equal(verity_uuid, id))
 571                                         continue;
 572
 573                                 designator = PARTITION_ROOT_SECONDARY_VERITY;
 574                                 fstype = "DM_verity_hash";
 575                                 architecture = SECONDARY_ARCHITECTURE;
 576                                 rw = false;
 577                         }
 578 #endif
 579                         else if (sd_id128_equal(type_id, GPT_SWAP)) {
 580
 581                                 if (pflags & GPT_FLAG_NO_AUTO)
 582                                         continue;
 583
 584                                 designator = PARTITION_SWAP;
 585                                 fstype = "swap";
 586                         } else if (sd_id128_equal(type_id, GPT_LINUX_GENERIC)) {
 587
 588                                 if (pflags & GPT_FLAG_NO_AUTO)
 589                                         continue;
 590
 591                                 if (generic_node)
 592                                         multiple_generic = true;
 593                                 else {
 594                                         generic_nr = nr;
 595                                         generic_rw = !(pflags & GPT_FLAG_READ_ONLY);
 596                                         generic_uuid = id;
 597                                         generic_node = strdup(node);
 598                                         if (!generic_node)
 599                                                 return -ENOMEM;
 600                                 }
 601
 602                         } else if (sd_id128_equal(type_id, GPT_TMP)) {
 603
 604                                 if (pflags & GPT_FLAG_NO_AUTO)
 605                                         continue;
 606
 607                                 designator = PARTITION_TMP;
 608                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 609
 610                         } else if (sd_id128_equal(type_id, GPT_VAR)) {
 611
 612                                 if (pflags & GPT_FLAG_NO_AUTO)
 613                                         continue;
 614
 615                                 if (!FLAGS_SET(flags, DISSECT_IMAGE_RELAX_VAR_CHECK)) {
 616                                         sd_id128_t var_uuid;
 617
 618                                         /* For /var we insist that the uuid of the partition matches the
 619                                          * HMAC-SHA256 of the /var GPT partition type uuid, keyed by machine
 620                                          * ID. Why? Unlike the other partitions /var is inherently
 621                                          * installation specific, hence we need to be careful not to mount it
 622                                          * in the wrong installation. By hashing the partition UUID from
 623                                          * /etc/machine-id we can securely bind the partition to the
 624                                          * installation. */
 625
 626                                         r = sd_id128_get_machine_app_specific(GPT_VAR, &var_uuid);
 627                                         if (r < 0)
 628                                                 return r;
 629
 630                                         if (!sd_id128_equal(var_uuid, id)) {
 631                                                 log_debug("Found a /var/ partition, but its UUID didn't match our expectations, ignoring.");
 632                                                 continue;
 633                                         }
 634                                 }
 635
 636                                 designator = PARTITION_VAR;
 637                                 rw = !(pflags & GPT_FLAG_READ_ONLY);
 638                         }
 639
 640                         if (designator != _PARTITION_DESIGNATOR_INVALID) {
 641                                 _cleanup_free_ char *t = NULL, *n = NULL;
 642
 643                                 /* First one wins */
 644                                 if (m->partitions[designator].found)
 645                                         continue;
 646
 647                                 if (fstype) {
 648                                         t = strdup(fstype);
 649                                         if (!t)
 650                                                 return -ENOMEM;
 651                                 }
 652
 653                                 n = strdup(node);
 654                                 if (!n)
 655                                         return -ENOMEM;
 656
 657                                 m->partitions[designator] = (DissectedPartition) {
 658                                         .found = true,
 659                                         .partno = nr,
 660                                         .rw = rw,
 661                                         .architecture = architecture,
 662                                         .node = TAKE_PTR(n),
 663                                         .fstype = TAKE_PTR(t),
 664                                         .uuid = id,
 665                                 };
 666                         }
 667
 668                 } else if (is_mbr) {
 669
 670                         switch (blkid_partition_get_type(pp)) {
 671
 672                         case 0x83: /* Linux partition */
 673
 674                                 if (pflags != 0x80) /* Bootable flag */
 675                                         continue;
 676
 677                                 if (generic_node)
 678                                         multiple_generic = true;
 679                                 else {
 680                                         generic_nr = nr;
 681                                         generic_rw = true;
 682                                         generic_node = strdup(node);
 683                                         if (!generic_node)
 684                                                 return -ENOMEM;
 685                                 }
 686
 687                                 break;
 688
 689                         case 0xEA: { /* Boot Loader Spec extended $BOOT partition */
 690                                 _cleanup_free_ char *n = NULL;
 691                                 sd_id128_t id = SD_ID128_NULL;
 692                                 const char *sid;
 693
 694                                 /* First one wins */
 695                                 if (m->partitions[PARTITION_XBOOTLDR].found)
 696                                         continue;
 697
 698                                 sid = blkid_partition_get_uuid(pp);
 699                                 if (sid)
 700                                         (void) sd_id128_from_string(sid, &id);
 701
 702                                 n = strdup(node);
 703                                 if (!n)
 704                                         return -ENOMEM;
 705
 706                                 m->partitions[PARTITION_XBOOTLDR] = (DissectedPartition) {
 707                                         .found = true,
 708                                         .partno = nr,
 709                                         .rw = true,
 710                                         .architecture = _ARCHITECTURE_INVALID,
 711                                         .node = TAKE_PTR(n),
 712                                         .uuid = id,
 713                                 };
 714
 715                                 break;
 716                         }}
 717                 }
 718         }
 719
 720         if (!m->partitions[PARTITION_ROOT].found) {
 721                 /* No root partition found? Then let's see if ther's one for the secondary architecture. And if not
 722                  * either, then check if there's a single generic one, and use that. */
 723
 724                 if (m->partitions[PARTITION_ROOT_VERITY].found)
 725                         return -EADDRNOTAVAIL;
 726
 727                 if (m->partitions[PARTITION_ROOT_SECONDARY].found) {
 728                         m->partitions[PARTITION_ROOT] = m->partitions[PARTITION_ROOT_SECONDARY];
 729                         zero(m->partitions[PARTITION_ROOT_SECONDARY]);
 730
 731                         m->partitions[PARTITION_ROOT_VERITY] = m->partitions[PARTITION_ROOT_SECONDARY_VERITY];
 732                         zero(m->partitions[PARTITION_ROOT_SECONDARY_VERITY]);
 733
 734                 } else if (flags & DISSECT_IMAGE_REQUIRE_ROOT) {
 735
 736                         /* If the root has was set, then we won't fallback to a generic node, because the root hash
 737                          * decides */
 738                         if (root_hash)
 739                                 return -EADDRNOTAVAIL;
 740
 741                         /* If we didn't find a generic node, then we can't fix this up either */
 742                         if (!generic_node)
 743                                 return -ENXIO;
 744
 745                         /* If we didn't find a properly marked root partition, but we did find a single suitable
 746                          * generic Linux partition, then use this as root partition, if the caller asked for it. */
 747                         if (multiple_generic)
 748                                 return -ENOTUNIQ;
 749
 750                         m->partitions[PARTITION_ROOT] = (DissectedPartition) {
 751                                 .found = true,
 752                                 .rw = generic_rw,
 753                                 .partno = generic_nr,
 754                                 .architecture = _ARCHITECTURE_INVALID,
 755                                 .node = TAKE_PTR(generic_node),
 756                                 .uuid = generic_uuid,
 757                         };
 758                 }
 759         }
 760
 761         if (root_hash) {
 762                 if (!m->partitions[PARTITION_ROOT_VERITY].found || !m->partitions[PARTITION_ROOT].found)
 763                         return -EADDRNOTAVAIL;
 764
 765                 /* If we found the primary root with the hash, then we definitely want to suppress any secondary root
 766                  * (which would be weird, after all the root hash should only be assigned to one pair of
 767                  * partitions... */
 768                 m->partitions[PARTITION_ROOT_SECONDARY].found = false;
 769                 m->partitions[PARTITION_ROOT_SECONDARY_VERITY].found = false;
 770
 771                 /* If we found a verity setup, then the root partition is necessarily read-only. */
 772                 m->partitions[PARTITION_ROOT].rw = false;
 773
 774                 m->verity = true;
 775         }
 776
 777         blkid_free_probe(b);
 778         b = NULL;
 779
 780         /* Fill in file system types if we don't know them yet. */
 781         for (i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) {
 782                 DissectedPartition *p = m->partitions + i;
 783
 784                 if (!p->found)
 785                         continue;
 786
 787                 if (!p->fstype && p->node) {
 788                         r = probe_filesystem(p->node, &p->fstype);
 789                         if (r < 0 && r != -EUCLEAN)
 790                                 return r;
 791                 }
 792
 793                 if (streq_ptr(p->fstype, "crypto_LUKS"))
 794                         m->encrypted = true;
 795
 796                 if (p->fstype && fstype_is_ro(p->fstype))
 797                         p->rw = false;
 798         }
 799
 800         *ret = TAKE_PTR(m);
 801
 802         return 0;
 803 #else
 804         return -EOPNOTSUPP;
 805 #endif
 806 }
 807
 808 DissectedImage* dissected_image_unref(DissectedImage *m) {
 809         unsigned i;
 810
 811         if (!m)
 812                 return NULL;
 813
 814         for (i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) {
 815                 free(m->partitions[i].fstype);
 816                 free(m->partitions[i].node);
 817                 free(m->partitions[i].decrypted_fstype);
 818                 free(m->partitions[i].decrypted_node);
 819         }
 820
 821         free(m->hostname);
 822         strv_free(m->machine_info);
 823         strv_free(m->os_release);
 824
 825         return mfree(m);
 826 }
 827
 828 static int is_loop_device(const char *path) {
 829         char s[SYS_BLOCK_PATH_MAX("/../loop/")];
 830         struct stat st;
 831
 832         assert(path);
 833
 834         if (stat(path, &st) < 0)
 835                 return -errno;
 836
 837         if (!S_ISBLK(st.st_mode))
 838                 return -ENOTBLK;
 839
 840         xsprintf_sys_block_path(s, "/loop/", st.st_dev);
 841         if (access(s, F_OK) < 0) {
 842                 if (errno != ENOENT)
 843                         return -errno;
 844
 845                 /* The device itself isn't a loop device, but maybe it's a partition and its parent is? */
 846                 xsprintf_sys_block_path(s, "/../loop/", st.st_dev);
 847                 if (access(s, F_OK) < 0)
 848                         return errno == ENOENT ? false : -errno;
 849         }
 850
 851         return true;
 852 }
 853
 854 static int mount_partition(
 855                 DissectedPartition *m,
 856                 const char *where,
 857                 const char *directory,
 858                 uid_t uid_shift,
 859                 DissectImageFlags flags) {
 860
 861         _cleanup_free_ char *chased = NULL, *options = NULL;
 862         const char *p, *node, *fstype;
 863         bool rw;
 864         int r;
 865
 866         assert(m);
 867         assert(where);
 868
 869         node = m->decrypted_node ?: m->node;
 870         fstype = m->decrypted_fstype ?: m->fstype;
 871
 872         if (!m->found || !node || !fstype)
 873                 return 0;
 874
 875         /* Stacked encryption? Yuck */
 876         if (streq_ptr(fstype, "crypto_LUKS"))
 877                 return -ELOOP;
 878
 879         rw = m->rw && !(flags & DISSECT_IMAGE_READ_ONLY);
 880
 881         if (directory) {
 882                 r = chase_symlinks(directory, where, CHASE_PREFIX_ROOT, &chased, NULL);
 883                 if (r < 0)
 884                         return r;
 885
 886                 p = chased;
 887         } else
 888                 p = where;
 889
 890         /* If requested, turn on discard support. */
 891         if (fstype_can_discard(fstype) &&
 892             ((flags & DISSECT_IMAGE_DISCARD) ||
 893              ((flags & DISSECT_IMAGE_DISCARD_ON_LOOP) && is_loop_device(m->node)))) {
 894                 options = strdup("discard");
 895                 if (!options)
 896                         return -ENOMEM;
 897         }
 898
 899         if (uid_is_valid(uid_shift) && uid_shift != 0 && fstype_can_uid_gid(fstype)) {
 900                 _cleanup_free_ char *uid_option = NULL;
 901
 902                 if (asprintf(&uid_option, "uid=" UID_FMT ",gid=" GID_FMT, uid_shift, (gid_t) uid_shift) < 0)
 903                         return -ENOMEM;
 904
 905                 if (!strextend_with_separator(&options, ",", uid_option, NULL))
 906                         return -ENOMEM;
 907         }
 908
 909         r = mount_verbose(LOG_DEBUG, node, p, fstype, MS_NODEV|(rw ? 0 : MS_RDONLY), options);
 910         if (r < 0)
 911                 return r;
 912
 913         return 1;
 914 }
 915
 916 int dissected_image_mount(DissectedImage *m, const char *where, uid_t uid_shift, DissectImageFlags flags) {
 917         int r, boot_mounted;
 918
 919         assert(m);
 920         assert(where);
 921
 922         if (!m->partitions[PARTITION_ROOT].found)
 923                 return -ENXIO;
 924
 925         if ((flags & DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY) == 0) {
 926                 r = mount_partition(m->partitions + PARTITION_ROOT, where, NULL, uid_shift, flags);
 927                 if (r < 0)
 928                         return r;
 929
 930                 if (flags & DISSECT_IMAGE_VALIDATE_OS) {
 931                         r = path_is_os_tree(where);
 932                         if (r < 0)
 933                                 return r;
 934                         if (r == 0)
 935                                 return -EMEDIUMTYPE;
 936                 }
 937         }
 938
 939         if (flags & DISSECT_IMAGE_MOUNT_ROOT_ONLY)
 940                 return 0;
 941
 942         r = mount_partition(m->partitions + PARTITION_HOME, where, "/home", uid_shift, flags);
 943         if (r < 0)
 944                 return r;
 945
 946         r = mount_partition(m->partitions + PARTITION_SRV, where, "/srv", uid_shift, flags);
 947         if (r < 0)
 948                 return r;
 949
 950         r = mount_partition(m->partitions + PARTITION_VAR, where, "/var", uid_shift, flags);
 951         if (r < 0)
 952                 return r;
 953
 954         r = mount_partition(m->partitions + PARTITION_TMP, where, "/var/tmp", uid_shift, flags);
 955         if (r < 0)
 956                 return r;
 957
 958         boot_mounted = mount_partition(m->partitions + PARTITION_XBOOTLDR, where, "/boot", uid_shift, flags);
 959         if (boot_mounted < 0)
 960                 return boot_mounted;
 961
 962         if (m->partitions[PARTITION_ESP].found) {
 963                 /* Mount the ESP to /efi if it exists. If it doesn't exist, use /boot instead, but only if it
 964                  * exists and is empty, and we didn't already mount the XBOOTLDR partition into it. */
 965
 966                 r = chase_symlinks("/efi", where, CHASE_PREFIX_ROOT, NULL, NULL);
 967                 if (r >= 0) {
 968                         r = mount_partition(m->partitions + PARTITION_ESP, where, "/efi", uid_shift, flags);
 969                         if (r < 0)
 970                                 return r;
 971
 972                 } else if (boot_mounted <= 0) {
 973                         _cleanup_free_ char *p = NULL;
 974
 975                         r = chase_symlinks("/boot", where, CHASE_PREFIX_ROOT, &p, NULL);
 976                         if (r >= 0 && dir_is_empty(p) > 0) {
 977                                 r = mount_partition(m->partitions + PARTITION_ESP, where, "/boot", uid_shift, flags);
 978                                 if (r < 0)
 979                                         return r;
 980                         }
 981                 }
 982         }
 983
 984         return 0;
 985 }
 986
 987 #if HAVE_LIBCRYPTSETUP
 988 typedef struct DecryptedPartition {
 989         struct crypt_device *device;
 990         char *name;
 991         bool relinquished;
 992 } DecryptedPartition;
 993
 994 struct DecryptedImage {
 995         DecryptedPartition *decrypted;
 996         size_t n_decrypted;
 997         size_t n_allocated;
 998 };
 999 #endif
1000
1001 DecryptedImage* decrypted_image_unref(DecryptedImage* d) {
1002 #if HAVE_LIBCRYPTSETUP
1003         size_t i;
1004         int r;
1005
1006         if (!d)
1007                 return NULL;
1008
1009         for (i = 0; i < d->n_decrypted; i++) {
1010                 DecryptedPartition *p = d->decrypted + i;
1011
1012                 if (p->device && p->name && !p->relinquished) {
1013                         r = crypt_deactivate(p->device, p->name);
1014                         if (r < 0)
1015                                 log_debug_errno(r, "Failed to deactivate encrypted partition %s", p->name);
1016                 }
1017
1018                 if (p->device)
1019                         crypt_free(p->device);
1020                 free(p->name);
1021         }
1022
1023         free(d);
1024 #endif
1025         return NULL;
1026 }
1027
1028 #if HAVE_LIBCRYPTSETUP
1029
1030 static int make_dm_name_and_node(const void *original_node, const char *suffix, char **ret_name, char **ret_node) {
1031         _cleanup_free_ char *name = NULL, *node = NULL;
1032         const char *base;
1033
1034         assert(original_node);
1035         assert(suffix);
1036         assert(ret_name);
1037         assert(ret_node);
1038
1039         base = strrchr(original_node, '/');
1040         if (!base)
1041                 return -EINVAL;
1042         base++;
1043         if (isempty(base))
1044                 return -EINVAL;
1045
1046         name = strjoin(base, suffix);
1047         if (!name)
1048                 return -ENOMEM;
1049         if (!filename_is_valid(name))
1050                 return -EINVAL;
1051
1052         node = path_join(crypt_get_dir(), name);
1053         if (!node)
1054                 return -ENOMEM;
1055
1056         *ret_name = TAKE_PTR(name);
1057         *ret_node = TAKE_PTR(node);
1058
1059         return 0;
1060 }
1061
1062 static int decrypt_partition(
1063                 DissectedPartition *m,
1064                 const char *passphrase,
1065                 DissectImageFlags flags,
1066                 DecryptedImage *d) {
1067
1068         _cleanup_free_ char *node = NULL, *name = NULL;
1069         _cleanup_(crypt_freep) struct crypt_device *cd = NULL;
1070         int r;
1071
1072         assert(m);
1073         assert(d);
1074
1075         if (!m->found || !m->node || !m->fstype)
1076                 return 0;
1077
1078         if (!streq(m->fstype, "crypto_LUKS"))
1079                 return 0;
1080
1081         if (!passphrase)
1082                 return -ENOKEY;
1083
1084         r = make_dm_name_and_node(m->node, "-decrypted", &name, &node);
1085         if (r < 0)
1086                 return r;
1087
1088         if (!GREEDY_REALLOC0(d->decrypted, d->n_allocated, d->n_decrypted + 1))
1089                 return -ENOMEM;
1090
1091         r = crypt_init(&cd, m->node);
1092         if (r < 0)
1093                 return log_debug_errno(r, "Failed to initialize dm-crypt: %m");
1094
1095         r = crypt_load(cd, CRYPT_LUKS, NULL);
1096         if (r < 0)
1097                 return log_debug_errno(r, "Failed to load LUKS metadata: %m");
1098
1099         r = crypt_activate_by_passphrase(cd, name, CRYPT_ANY_SLOT, passphrase, strlen(passphrase),
1100                                          ((flags & DISSECT_IMAGE_READ_ONLY) ? CRYPT_ACTIVATE_READONLY : 0) |
1101                                          ((flags & DISSECT_IMAGE_DISCARD_ON_CRYPTO) ? CRYPT_ACTIVATE_ALLOW_DISCARDS : 0));
1102         if (r < 0) {
1103                 log_debug_errno(r, "Failed to activate LUKS device: %m");
1104                 return r == -EPERM ? -EKEYREJECTED : r;
1105         }
1106
1107         d->decrypted[d->n_decrypted].name = TAKE_PTR(name);
1108         d->decrypted[d->n_decrypted].device = TAKE_PTR(cd);
1109         d->n_decrypted++;
1110
1111         m->decrypted_node = TAKE_PTR(node);
1112
1113         return 0;
1114 }
1115
1116 static int verity_partition(
1117                 DissectedPartition *m,
1118                 DissectedPartition *v,
1119                 const void *root_hash,
1120                 size_t root_hash_size,
1121                 DissectImageFlags flags,
1122                 DecryptedImage *d) {
1123
1124         _cleanup_free_ char *node = NULL, *name = NULL;
1125         _cleanup_(crypt_freep) struct crypt_device *cd = NULL;
1126         int r;
1127
1128         assert(m);
1129         assert(v);
1130
1131         if (!root_hash)
1132                 return 0;
1133
1134         if (!m->found || !m->node || !m->fstype)
1135                 return 0;
1136         if (!v->found || !v->node || !v->fstype)
1137                 return 0;
1138
1139         if (!streq(v->fstype, "DM_verity_hash"))
1140                 return 0;
1141
1142         r = make_dm_name_and_node(m->node, "-verity", &name, &node);
1143         if (r < 0)
1144                 return r;
1145
1146         if (!GREEDY_REALLOC0(d->decrypted, d->n_allocated, d->n_decrypted + 1))
1147                 return -ENOMEM;
1148
1149         r = crypt_init(&cd, v->node);
1150         if (r < 0)
1151                 return r;
1152
1153         r = crypt_load(cd, CRYPT_VERITY, NULL);
1154         if (r < 0)
1155                 return r;
1156
1157         r = crypt_set_data_device(cd, m->node);
1158         if (r < 0)
1159                 return r;
1160
1161         r = crypt_activate_by_volume_key(cd, name, root_hash, root_hash_size, CRYPT_ACTIVATE_READONLY);
1162         if (r < 0)
1163                 return r;
1164
1165         d->decrypted[d->n_decrypted].name = TAKE_PTR(name);
1166         d->decrypted[d->n_decrypted].device = TAKE_PTR(cd);
1167         d->n_decrypted++;
1168
1169         m->decrypted_node = TAKE_PTR(node);
1170
1171         return 0;
1172 }
1173 #endif
1174
1175 int dissected_image_decrypt(
1176                 DissectedImage *m,
1177                 const char *passphrase,
1178                 const void *root_hash,
1179                 size_t root_hash_size,
1180                 DissectImageFlags flags,
1181                 DecryptedImage **ret) {
1182
1183 #if HAVE_LIBCRYPTSETUP
1184         _cleanup_(decrypted_image_unrefp) DecryptedImage *d = NULL;
1185         unsigned i;
1186         int r;
1187 #endif
1188
1189         assert(m);
1190         assert(root_hash || root_hash_size == 0);
1191
1192         /* Returns:
1193          *
1194          *      = 0           → There was nothing to decrypt
1195          *      > 0           → Decrypted successfully
1196          *      -ENOKEY       → There's something to decrypt but no key was supplied
1197          *      -EKEYREJECTED → Passed key was not correct
1198          */
1199
1200         if (root_hash && root_hash_size < sizeof(sd_id128_t))
1201                 return -EINVAL;
1202
1203         if (!m->encrypted && !m->verity) {
1204                 *ret = NULL;
1205                 return 0;
1206         }
1207
1208 #if HAVE_LIBCRYPTSETUP
1209         d = new0(DecryptedImage, 1);
1210         if (!d)
1211                 return -ENOMEM;
1212
1213         for (i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) {
1214                 DissectedPartition *p = m->partitions + i;
1215                 int k;
1216
1217                 if (!p->found)
1218                         continue;
1219
1220                 r = decrypt_partition(p, passphrase, flags, d);
1221                 if (r < 0)
1222                         return r;
1223
1224                 k = PARTITION_VERITY_OF(i);
1225                 if (k >= 0) {
1226                         r = verity_partition(p, m->partitions + k, root_hash, root_hash_size, flags, d);
1227                         if (r < 0)
1228                                 return r;
1229                 }
1230
1231                 if (!p->decrypted_fstype && p->decrypted_node) {
1232                         r = probe_filesystem(p->decrypted_node, &p->decrypted_fstype);
1233                         if (r < 0 && r != -EUCLEAN)
1234                                 return r;
1235                 }
1236         }
1237
1238         *ret = TAKE_PTR(d);
1239
1240         return 1;
1241 #else
1242         return -EOPNOTSUPP;
1243 #endif
1244 }
1245
1246 int dissected_image_decrypt_interactively(
1247                 DissectedImage *m,
1248                 const char *passphrase,
1249                 const void *root_hash,
1250                 size_t root_hash_size,
1251                 DissectImageFlags flags,
1252                 DecryptedImage **ret) {
1253
1254         _cleanup_strv_free_erase_ char **z = NULL;
1255         int n = 3, r;
1256
1257         if (passphrase)
1258                 n--;
1259
1260         for (;;) {
1261                 r = dissected_image_decrypt(m, passphrase, root_hash, root_hash_size, flags, ret);
1262                 if (r >= 0)
1263                         return r;
1264                 if (r == -EKEYREJECTED)
1265                         log_error_errno(r, "Incorrect passphrase, try again!");
1266                 else if (r != -ENOKEY)
1267                         return log_error_errno(r, "Failed to decrypt image: %m");
1268
1269                 if (--n < 0)
1270                         return log_error_errno(SYNTHETIC_ERRNO(EKEYREJECTED),
1271                                                "Too many retries.");
1272
1273                 z = strv_free(z);
1274
1275                 r = ask_password_auto("Please enter image passphrase:", NULL, "dissect", "dissect", USEC_INFINITY, 0, &z);
1276                 if (r < 0)
1277                         return log_error_errno(r, "Failed to query for passphrase: %m");
1278
1279                 passphrase = z[0];
1280         }
1281 }
1282
1283 int decrypted_image_relinquish(DecryptedImage *d) {
1284
1285 #if HAVE_LIBCRYPTSETUP
1286         size_t i;
1287         int r;
1288 #endif
1289
1290         assert(d);
1291
1292         /* Turns on automatic removal after the last use ended for all DM devices of this image, and sets a boolean so
1293          * that we don't clean it up ourselves either anymore */
1294
1295 #if HAVE_LIBCRYPTSETUP
1296         for (i = 0; i < d->n_decrypted; i++) {
1297                 DecryptedPartition *p = d->decrypted + i;
1298
1299                 if (p->relinquished)
1300                         continue;
1301
1302                 r = dm_deferred_remove(p->name);
1303                 if (r < 0)
1304                         return log_debug_errno(r, "Failed to mark %s for auto-removal: %m", p->name);
1305
1306                 p->relinquished = true;
1307         }
1308 #endif
1309
1310         return 0;
1311 }
1312
1313 int root_hash_load(const char *image, void **ret, size_t *ret_size) {
1314         _cleanup_free_ char *text = NULL;
1315         _cleanup_free_ void *k = NULL;
1316         size_t l;
1317         int r;
1318
1319         assert(image);
1320         assert(ret);
1321         assert(ret_size);
1322
1323         if (is_device_path(image)) {
1324                 /* If we are asked to load the root hash for a device node, exit early */
1325                 *ret = NULL;
1326                 *ret_size = 0;
1327                 return 0;
1328         }
1329
1330         r = getxattr_malloc(image, "user.verity.roothash", &text, true);
1331         if (r < 0) {
1332                 char *fn, *e, *n;
1333
1334                 if (!IN_SET(r, -ENODATA, -EOPNOTSUPP, -ENOENT))
1335                         return r;
1336
1337                 fn = newa(char, strlen(image) + STRLEN(".roothash") + 1);
1338                 n = stpcpy(fn, image);
1339                 e = endswith(fn, ".raw");
1340                 if (e)
1341                         n = e;
1342
1343                 strcpy(n, ".roothash");
1344
1345                 r = read_one_line_file(fn, &text);
1346                 if (r == -ENOENT) {
1347                         *ret = NULL;
1348                         *ret_size = 0;
1349                         return 0;
1350                 }
1351                 if (r < 0)
1352                         return r;
1353         }
1354
1355         r = unhexmem(text, strlen(text), &k, &l);
1356         if (r < 0)
1357                 return r;
1358         if (l < sizeof(sd_id128_t))
1359                 return -EINVAL;
1360
1361         *ret = TAKE_PTR(k);
1362         *ret_size = l;
1363
1364         return 1;
1365 }
1366
1367 int dissected_image_acquire_metadata(DissectedImage *m) {
1368
1369         enum {
1370                 META_HOSTNAME,
1371                 META_MACHINE_ID,
1372                 META_MACHINE_INFO,
1373                 META_OS_RELEASE,
1374                 _META_MAX,
1375         };
1376
1377         static const char *const paths[_META_MAX] = {
1378                 [META_HOSTNAME]     = "/etc/hostname\0",
1379                 [META_MACHINE_ID]   = "/etc/machine-id\0",
1380                 [META_MACHINE_INFO] = "/etc/machine-info\0",
1381                 [META_OS_RELEASE]   = "/etc/os-release\0"
1382                                       "/usr/lib/os-release\0",
1383         };
1384
1385         _cleanup_strv_free_ char **machine_info = NULL, **os_release = NULL;
1386         _cleanup_(rmdir_and_freep) char *t = NULL;
1387         _cleanup_(sigkill_waitp) pid_t child = 0;
1388         sd_id128_t machine_id = SD_ID128_NULL;
1389         _cleanup_free_ char *hostname = NULL;
1390         unsigned n_meta_initialized = 0, k;
1391         int fds[2 * _META_MAX], r;
1392
1393         BLOCK_SIGNALS(SIGCHLD);
1394
1395         assert(m);
1396
1397         for (; n_meta_initialized < _META_MAX; n_meta_initialized ++)
1398                 if (pipe2(fds + 2*n_meta_initialized, O_CLOEXEC) < 0) {
1399                         r = -errno;
1400                         goto finish;
1401                 }
1402
1403         r = mkdtemp_malloc("/tmp/dissect-XXXXXX", &t);
1404         if (r < 0)
1405                 goto finish;
1406
1407         r = safe_fork("(sd-dissect)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_NEW_MOUNTNS|FORK_MOUNTNS_SLAVE, &child);
1408         if (r < 0)
1409                 goto finish;
1410         if (r == 0) {
1411                 r = dissected_image_mount(m, t, UID_INVALID, DISSECT_IMAGE_READ_ONLY|DISSECT_IMAGE_MOUNT_ROOT_ONLY|DISSECT_IMAGE_VALIDATE_OS);
1412                 if (r < 0) {
1413                         log_debug_errno(r, "Failed to mount dissected image: %m");
1414                         _exit(EXIT_FAILURE);
1415                 }
1416
1417                 for (k = 0; k < _META_MAX; k++) {
1418                         _cleanup_close_ int fd = -1;
1419                         const char *p;
1420
1421                         fds[2*k] = safe_close(fds[2*k]);
1422
1423                         NULSTR_FOREACH(p, paths[k]) {
1424                                 fd = chase_symlinks_and_open(p, t, CHASE_PREFIX_ROOT, O_RDONLY|O_CLOEXEC|O_NOCTTY, NULL);
1425                                 if (fd >= 0)
1426                                         break;
1427                         }
1428                         if (fd < 0) {
1429                                 log_debug_errno(fd, "Failed to read %s file of image, ignoring: %m", paths[k]);
1430                                 continue;
1431                         }
1432
1433                         r = copy_bytes(fd, fds[2*k+1], (uint64_t) -1, 0);
1434                         if (r < 0)
1435                                 _exit(EXIT_FAILURE);
1436
1437                         fds[2*k+1] = safe_close(fds[2*k+1]);
1438                 }
1439
1440                 _exit(EXIT_SUCCESS);
1441         }
1442
1443         for (k = 0; k < _META_MAX; k++) {
1444                 _cleanup_fclose_ FILE *f = NULL;
1445
1446                 fds[2*k+1] = safe_close(fds[2*k+1]);
1447
1448                 f = fdopen(fds[2*k], "r");
1449                 if (!f) {
1450                         r = -errno;
1451                         goto finish;
1452                 }
1453
1454                 fds[2*k] = -1;
1455
1456                 switch (k) {
1457
1458                 case META_HOSTNAME:
1459                         r = read_etc_hostname_stream(f, &hostname);
1460                         if (r < 0)
1461                                 log_debug_errno(r, "Failed to read /etc/hostname: %m");
1462
1463                         break;
1464
1465                 case META_MACHINE_ID: {
1466                         _cleanup_free_ char *line = NULL;
1467
1468                         r = read_line(f, LONG_LINE_MAX, &line);
1469                         if (r < 0)
1470                                 log_debug_errno(r, "Failed to read /etc/machine-id: %m");
1471                         else if (r == 33) {
1472                                 r = sd_id128_from_string(line, &machine_id);
1473                                 if (r < 0)
1474                                         log_debug_errno(r, "Image contains invalid /etc/machine-id: %s", line);
1475                         } else if (r == 0)
1476                                 log_debug("/etc/machine-id file is empty.");
1477                         else
1478                                 log_debug("/etc/machine-id has unexpected length %i.", r);
1479
1480                         break;
1481                 }
1482
1483                 case META_MACHINE_INFO:
1484                         r = load_env_file_pairs(f, "machine-info", &machine_info);
1485                         if (r < 0)
1486                                 log_debug_errno(r, "Failed to read /etc/machine-info: %m");
1487
1488                         break;
1489
1490                 case META_OS_RELEASE:
1491                         r = load_env_file_pairs(f, "os-release", &os_release);
1492                         if (r < 0)
1493                                 log_debug_errno(r, "Failed to read OS release file: %m");
1494
1495                         break;
1496                 }
1497         }
1498
1499         r = wait_for_terminate_and_check("(sd-dissect)", child, 0);
1500         child = 0;
1501         if (r < 0)
1502                 goto finish;
1503         if (r != EXIT_SUCCESS)
1504                 return -EPROTO;
1505
1506         free_and_replace(m->hostname, hostname);
1507         m->machine_id = machine_id;
1508         strv_free_and_replace(m->machine_info, machine_info);
1509         strv_free_and_replace(m->os_release, os_release);
1510
1511 finish:
1512         for (k = 0; k < n_meta_initialized; k++)
1513                 safe_close_pair(fds + 2*k);
1514
1515         return r;
1516 }
1517
1518 int dissect_image_and_warn(
1519                 int fd,
1520                 const char *name,
1521                 const void *root_hash,
1522                 size_t root_hash_size,
1523                 DissectImageFlags flags,
1524                 DissectedImage **ret) {
1525
1526         _cleanup_free_ char *buffer = NULL;
1527         int r;
1528
1529         if (!name) {
1530                 r = fd_get_path(fd, &buffer);
1531                 if (r < 0)
1532                         return r;
1533
1534                 name = buffer;
1535         }
1536
1537         r = dissect_image(fd, root_hash, root_hash_size, flags, ret);
1538
1539         switch (r) {
1540
1541         case -EOPNOTSUPP:
1542                 return log_error_errno(r, "Dissecting images is not supported, compiled without blkid support.");
1543
1544         case -ENOPKG:
1545                 return log_error_errno(r, "Couldn't identify a suitable partition table or file system in '%s'.", name);
1546
1547         case -EADDRNOTAVAIL:
1548                 return log_error_errno(r, "No root partition for specified root hash found in '%s'.", name);
1549
1550         case -ENOTUNIQ:
1551                 return log_error_errno(r, "Multiple suitable root partitions found in image '%s'.", name);
1552
1553         case -ENXIO:
1554                 return log_error_errno(r, "No suitable root partition found in image '%s'.", name);
1555
1556         case -EPROTONOSUPPORT:
1557                 return log_error_errno(r, "Device '%s' is loopback block device with partition scanning turned off, please turn it on.", name);
1558
1559         default:
1560                 if (r < 0)
1561                         return log_error_errno(r, "Failed to dissect image '%s': %m", name);
1562
1563                 return r;
1564         }
1565 }
1566
1567 static const char *const partition_designator_table[] = {
1568         [PARTITION_ROOT] = "root",
1569         [PARTITION_ROOT_SECONDARY] = "root-secondary",
1570         [PARTITION_HOME] = "home",
1571         [PARTITION_SRV] = "srv",
1572         [PARTITION_ESP] = "esp",
1573         [PARTITION_XBOOTLDR] = "xbootldr",
1574         [PARTITION_SWAP] = "swap",
1575         [PARTITION_ROOT_VERITY] = "root-verity",
1576         [PARTITION_ROOT_SECONDARY_VERITY] = "root-secondary-verity",
1577         [PARTITION_TMP] = "tmp",
1578         [PARTITION_VAR] = "var",
1579 };
1580
1581 DEFINE_STRING_TABLE_LOOKUP(partition_designator, int);