src/machine/machine.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <errno.h>
   4 #include <unistd.h>
   5 #include <sys/stat.h>
   6
   7 #include "sd-messages.h"
   8
   9 #include "alloc-util.h"
  10 #include "bus-error.h"
  11 #include "bus-locator.h"
  12 #include "bus-util.h"
  13 #include "env-file.h"
  14 #include "errno-util.h"
  15 #include "escape.h"
  16 #include "extract-word.h"
  17 #include "fd-util.h"
  18 #include "fileio.h"
  19 #include "format-util.h"
  20 #include "hashmap.h"
  21 #include "machine-dbus.h"
  22 #include "machine.h"
  23 #include "mkdir-label.h"
  24 #include "parse-util.h"
  25 #include "path-util.h"
  26 #include "process-util.h"
  27 #include "serialize.h"
  28 #include "special.h"
  29 #include "stdio-util.h"
  30 #include "string-table.h"
  31 #include "terminal-util.h"
  32 #include "tmpfile-util.h"
  33 #include "unit-name.h"
  34 #include "user-util.h"
  35
  36 Machine* machine_new(Manager *manager, MachineClass class, const char *name) {
  37         Machine *m;
  38
  39         assert(manager);
  40         assert(class < _MACHINE_CLASS_MAX);
  41         assert(name);
  42
  43         /* Passing class == _MACHINE_CLASS_INVALID here is fine. It
  44          * means as much as "we don't know yet", and that we'll figure
  45          * it out later when loading the state file. */
  46
  47         m = new0(Machine, 1);
  48         if (!m)
  49                 return NULL;
  50
  51         m->name = strdup(name);
  52         if (!m->name)
  53                 goto fail;
  54
  55         if (class != MACHINE_HOST) {
  56                 m->state_file = path_join("/run/systemd/machines", m->name);
  57                 if (!m->state_file)
  58                         goto fail;
  59         }
  60
  61         m->class = class;
  62
  63         if (hashmap_put(manager->machines, m->name, m) < 0)
  64                 goto fail;
  65
  66         m->manager = manager;
  67
  68         return m;
  69
  70 fail:
  71         free(m->state_file);
  72         free(m->name);
  73         return mfree(m);
  74 }
  75
  76 Machine* machine_free(Machine *m) {
  77         if (!m)
  78                 return NULL;
  79
  80         while (m->operations)
  81                 operation_free(m->operations);
  82
  83         if (m->in_gc_queue)
  84                 LIST_REMOVE(gc_queue, m->manager->machine_gc_queue, m);
  85
  86         machine_release_unit(m);
  87
  88         free(m->scope_job);
  89
  90         (void) hashmap_remove(m->manager->machines, m->name);
  91
  92         if (m->manager->host_machine == m)
  93                 m->manager->host_machine = NULL;
  94
  95         if (m->leader > 0)
  96                 (void) hashmap_remove_value(m->manager->machine_leaders, PID_TO_PTR(m->leader), m);
  97
  98         sd_bus_message_unref(m->create_message);
  99
 100         free(m->name);
 101         free(m->state_file);
 102         free(m->service);
 103         free(m->root_directory);
 104         free(m->netif);
 105         return mfree(m);
 106 }
 107
 108 int machine_save(Machine *m) {
 109         _cleanup_free_ char *temp_path = NULL;
 110         _cleanup_fclose_ FILE *f = NULL;
 111         int r;
 112
 113         assert(m);
 114
 115         if (!m->state_file)
 116                 return 0;
 117
 118         if (!m->started)
 119                 return 0;
 120
 121         r = mkdir_safe_label("/run/systemd/machines", 0755, 0, 0, MKDIR_WARN_MODE);
 122         if (r < 0)
 123                 goto fail;
 124
 125         r = fopen_temporary(m->state_file, &f, &temp_path);
 126         if (r < 0)
 127                 goto fail;
 128
 129         (void) fchmod(fileno(f), 0644);
 130
 131         fprintf(f,
 132                 "# This is private data. Do not parse.\n"
 133                 "NAME=%s\n",
 134                 m->name);
 135
 136         if (m->unit) {
 137                 _cleanup_free_ char *escaped = NULL;
 138
 139                 escaped = cescape(m->unit);
 140                 if (!escaped) {
 141                         r = -ENOMEM;
 142                         goto fail;
 143                 }
 144
 145                 fprintf(f, "SCOPE=%s\n", escaped); /* We continue to call this "SCOPE=" because it is internal only, and we want to stay compatible with old files */
 146         }
 147
 148         if (m->scope_job)
 149                 fprintf(f, "SCOPE_JOB=%s\n", m->scope_job);
 150
 151         if (m->service) {
 152                 _cleanup_free_ char *escaped = NULL;
 153
 154                 escaped = cescape(m->service);
 155                 if (!escaped) {
 156                         r = -ENOMEM;
 157                         goto fail;
 158                 }
 159                 fprintf(f, "SERVICE=%s\n", escaped);
 160         }
 161
 162         if (m->root_directory) {
 163                 _cleanup_free_ char *escaped = NULL;
 164
 165                 escaped = cescape(m->root_directory);
 166                 if (!escaped) {
 167                         r = -ENOMEM;
 168                         goto fail;
 169                 }
 170                 fprintf(f, "ROOT=%s\n", escaped);
 171         }
 172
 173         if (!sd_id128_is_null(m->id))
 174                 fprintf(f, "ID=" SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(m->id));
 175
 176         if (m->leader != 0)
 177                 fprintf(f, "LEADER="PID_FMT"\n", m->leader);
 178
 179         if (m->class != _MACHINE_CLASS_INVALID)
 180                 fprintf(f, "CLASS=%s\n", machine_class_to_string(m->class));
 181
 182         if (dual_timestamp_is_set(&m->timestamp))
 183                 fprintf(f,
 184                         "REALTIME="USEC_FMT"\n"
 185                         "MONOTONIC="USEC_FMT"\n",
 186                         m->timestamp.realtime,
 187                         m->timestamp.monotonic);
 188
 189         if (m->n_netif > 0) {
 190                 size_t i;
 191
 192                 fputs("NETIF=", f);
 193
 194                 for (i = 0; i < m->n_netif; i++) {
 195                         if (i != 0)
 196                                 fputc(' ', f);
 197
 198                         fprintf(f, "%i", m->netif[i]);
 199                 }
 200
 201                 fputc('\n', f);
 202         }
 203
 204         r = fflush_and_check(f);
 205         if (r < 0)
 206                 goto fail;
 207
 208         if (rename(temp_path, m->state_file) < 0) {
 209                 r = -errno;
 210                 goto fail;
 211         }
 212
 213         if (m->unit) {
 214                 char *sl;
 215
 216                 /* Create a symlink from the unit name to the machine
 217                  * name, so that we can quickly find the machine for
 218                  * each given unit. Ignore error. */
 219                 sl = strjoina("/run/systemd/machines/unit:", m->unit);
 220                 (void) symlink(m->name, sl);
 221         }
 222
 223         return 0;
 224
 225 fail:
 226         (void) unlink(m->state_file);
 227
 228         if (temp_path)
 229                 (void) unlink(temp_path);
 230
 231         return log_error_errno(r, "Failed to save machine data %s: %m", m->state_file);
 232 }
 233
 234 static void machine_unlink(Machine *m) {
 235         assert(m);
 236
 237         if (m->unit) {
 238                 char *sl;
 239
 240                 sl = strjoina("/run/systemd/machines/unit:", m->unit);
 241                 (void) unlink(sl);
 242         }
 243
 244         if (m->state_file)
 245                 (void) unlink(m->state_file);
 246 }
 247
 248 int machine_load(Machine *m) {
 249         _cleanup_free_ char *realtime = NULL, *monotonic = NULL, *id = NULL, *leader = NULL, *class = NULL, *netif = NULL;
 250         int r;
 251
 252         assert(m);
 253
 254         if (!m->state_file)
 255                 return 0;
 256
 257         r = parse_env_file(NULL, m->state_file,
 258                            "SCOPE",     &m->unit,
 259                            "SCOPE_JOB", &m->scope_job,
 260                            "SERVICE",   &m->service,
 261                            "ROOT",      &m->root_directory,
 262                            "ID",        &id,
 263                            "LEADER",    &leader,
 264                            "CLASS",     &class,
 265                            "REALTIME",  &realtime,
 266                            "MONOTONIC", &monotonic,
 267                            "NETIF",     &netif);
 268         if (r == -ENOENT)
 269                 return 0;
 270         if (r < 0)
 271                 return log_error_errno(r, "Failed to read %s: %m", m->state_file);
 272
 273         if (id)
 274                 sd_id128_from_string(id, &m->id);
 275
 276         if (leader)
 277                 parse_pid(leader, &m->leader);
 278
 279         if (class) {
 280                 MachineClass c;
 281
 282                 c = machine_class_from_string(class);
 283                 if (c >= 0)
 284                         m->class = c;
 285         }
 286
 287         if (realtime)
 288                 (void) deserialize_usec(realtime, &m->timestamp.realtime);
 289         if (monotonic)
 290                 (void) deserialize_usec(monotonic, &m->timestamp.monotonic);
 291
 292         if (netif) {
 293                 _cleanup_free_ int *ni = NULL;
 294                 size_t nr = 0;
 295                 const char *p;
 296
 297                 p = netif;
 298                 for (;;) {
 299                         _cleanup_free_ char *word = NULL;
 300
 301                         r = extract_first_word(&p, &word, NULL, 0);
 302                         if (r == 0)
 303                                 break;
 304                         if (r == -ENOMEM)
 305                                 return log_oom();
 306                         if (r < 0) {
 307                                 log_warning_errno(r, "Failed to parse NETIF: %s", netif);
 308                                 break;
 309                         }
 310
 311                         r = parse_ifindex(word);
 312                         if (r < 0)
 313                                 continue;
 314
 315                         if (!GREEDY_REALLOC(ni, nr + 1))
 316                                 return log_oom();
 317
 318                         ni[nr++] = r;
 319                 }
 320
 321                 free_and_replace(m->netif, ni);
 322                 m->n_netif = nr;
 323         }
 324
 325         return r;
 326 }
 327
 328 static int machine_start_scope(
 329                 Machine *machine,
 330                 sd_bus_message *more_properties,
 331                 sd_bus_error *error) {
 332
 333         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *reply = NULL;
 334         _cleanup_free_ char *escaped = NULL, *unit = NULL;
 335         const char *description;
 336         int r;
 337
 338         assert(machine);
 339         assert(machine->leader > 0);
 340         assert(!machine->unit);
 341
 342         escaped = unit_name_escape(machine->name);
 343         if (!escaped)
 344                 return log_oom();
 345
 346         unit = strjoin("machine-", escaped, ".scope");
 347         if (!unit)
 348                 return log_oom();
 349
 350         r = bus_message_new_method_call(
 351                         machine->manager->bus,
 352                         &m,
 353                         bus_systemd_mgr,
 354                         "StartTransientUnit");
 355         if (r < 0)
 356                 return r;
 357
 358         r = sd_bus_message_append(m, "ss", unit, "fail");
 359         if (r < 0)
 360                 return r;
 361
 362         r = sd_bus_message_open_container(m, 'a', "(sv)");
 363         if (r < 0)
 364                 return r;
 365
 366         r = sd_bus_message_append(m, "(sv)", "Slice", "s", SPECIAL_MACHINE_SLICE);
 367         if (r < 0)
 368                 return r;
 369
 370         description = strjoina(machine->class == MACHINE_VM ? "Virtual Machine " : "Container ", machine->name);
 371         r = sd_bus_message_append(m, "(sv)", "Description", "s", description);
 372         if (r < 0)
 373                 return r;
 374
 375         r = sd_bus_message_append(m, "(sv)(sv)(sv)(sv)(sv)",
 376                                   "PIDs", "au", 1, machine->leader,
 377                                   "Delegate", "b", 1,
 378                                   "CollectMode", "s", "inactive-or-failed",
 379                                   "AddRef", "b", 1,
 380                                   "TasksMax", "t", UINT64_C(16384));
 381         if (r < 0)
 382                 return r;
 383
 384         if (more_properties) {
 385                 r = sd_bus_message_copy(m, more_properties, true);
 386                 if (r < 0)
 387                         return r;
 388         }
 389
 390         r = sd_bus_message_close_container(m);
 391         if (r < 0)
 392                 return r;
 393
 394         r = sd_bus_message_append(m, "a(sa(sv))", 0);
 395         if (r < 0)
 396                 return r;
 397
 398         r = sd_bus_call(NULL, m, 0, error, &reply);
 399         if (r < 0)
 400                 return r;
 401
 402         machine->unit = TAKE_PTR(unit);
 403         machine->referenced = true;
 404
 405         const char *job;
 406         r = sd_bus_message_read(reply, "o", &job);
 407         if (r < 0)
 408                 return r;
 409
 410         return free_and_strdup(&machine->scope_job, job);
 411 }
 412
 413 static int machine_ensure_scope(Machine *m, sd_bus_message *properties, sd_bus_error *error) {
 414         int r;
 415
 416         assert(m);
 417         assert(m->class != MACHINE_HOST);
 418
 419         if (!m->unit) {
 420                 r = machine_start_scope(m, properties, error);
 421                 if (r < 0)
 422                         return log_error_errno(r, "Failed to start machine scope: %s", bus_error_message(error, r));
 423         }
 424
 425         assert(m->unit);
 426         hashmap_put(m->manager->machine_units, m->unit, m);
 427
 428         return 0;
 429 }
 430
 431 int machine_start(Machine *m, sd_bus_message *properties, sd_bus_error *error) {
 432         int r;
 433
 434         assert(m);
 435
 436         if (!IN_SET(m->class, MACHINE_CONTAINER, MACHINE_VM))
 437                 return -EOPNOTSUPP;
 438
 439         if (m->started)
 440                 return 0;
 441
 442         r = hashmap_put(m->manager->machine_leaders, PID_TO_PTR(m->leader), m);
 443         if (r < 0)
 444                 return r;
 445
 446         /* Create cgroup */
 447         r = machine_ensure_scope(m, properties, error);
 448         if (r < 0)
 449                 return r;
 450
 451         log_struct(LOG_INFO,
 452                    "MESSAGE_ID=" SD_MESSAGE_MACHINE_START_STR,
 453                    "NAME=%s", m->name,
 454                    "LEADER="PID_FMT, m->leader,
 455                    LOG_MESSAGE("New machine %s.", m->name));
 456
 457         if (!dual_timestamp_is_set(&m->timestamp))
 458                 dual_timestamp_get(&m->timestamp);
 459
 460         m->started = true;
 461
 462         /* Save new machine data */
 463         machine_save(m);
 464
 465         machine_send_signal(m, true);
 466         (void) manager_enqueue_nscd_cache_flush(m->manager);
 467
 468         return 0;
 469 }
 470
 471 int machine_stop(Machine *m) {
 472         int r;
 473
 474         assert(m);
 475
 476         if (!IN_SET(m->class, MACHINE_CONTAINER, MACHINE_VM))
 477                 return -EOPNOTSUPP;
 478
 479         if (m->unit) {
 480                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 481                 char *job = NULL;
 482
 483                 r = manager_stop_unit(m->manager, m->unit, &error, &job);
 484                 if (r < 0)
 485                         return log_error_errno(r, "Failed to stop machine scope: %s", bus_error_message(&error, r));
 486
 487                 free_and_replace(m->scope_job, job);
 488         }
 489
 490         m->stopping = true;
 491
 492         machine_save(m);
 493         (void) manager_enqueue_nscd_cache_flush(m->manager);
 494
 495         return 0;
 496 }
 497
 498 int machine_finalize(Machine *m) {
 499         assert(m);
 500
 501         if (m->started) {
 502                 log_struct(LOG_INFO,
 503                            "MESSAGE_ID=" SD_MESSAGE_MACHINE_STOP_STR,
 504                            "NAME=%s", m->name,
 505                            "LEADER="PID_FMT, m->leader,
 506                            LOG_MESSAGE("Machine %s terminated.", m->name));
 507
 508                 m->stopping = true; /* The machine is supposed to be going away. Don't try to kill it. */
 509         }
 510
 511         machine_unlink(m);
 512         machine_add_to_gc_queue(m);
 513
 514         if (m->started) {
 515                 machine_send_signal(m, false);
 516                 m->started = false;
 517         }
 518
 519         return 0;
 520 }
 521
 522 bool machine_may_gc(Machine *m, bool drop_not_started) {
 523         assert(m);
 524
 525         if (m->class == MACHINE_HOST)
 526                 return false;
 527
 528         if (drop_not_started && !m->started)
 529                 return true;
 530
 531         if (m->scope_job && manager_job_is_active(m->manager, m->scope_job))
 532                 return false;
 533
 534         if (m->unit && manager_unit_is_active(m->manager, m->unit))
 535                 return false;
 536
 537         return true;
 538 }
 539
 540 void machine_add_to_gc_queue(Machine *m) {
 541         assert(m);
 542
 543         if (m->in_gc_queue)
 544                 return;
 545
 546         LIST_PREPEND(gc_queue, m->manager->machine_gc_queue, m);
 547         m->in_gc_queue = true;
 548 }
 549
 550 MachineState machine_get_state(Machine *s) {
 551         assert(s);
 552
 553         if (s->class == MACHINE_HOST)
 554                 return MACHINE_RUNNING;
 555
 556         if (s->stopping)
 557                 return MACHINE_CLOSING;
 558
 559         if (s->scope_job)
 560                 return MACHINE_OPENING;
 561
 562         return MACHINE_RUNNING;
 563 }
 564
 565 int machine_kill(Machine *m, KillWho who, int signo) {
 566         assert(m);
 567
 568         if (!IN_SET(m->class, MACHINE_VM, MACHINE_CONTAINER))
 569                 return -EOPNOTSUPP;
 570
 571         if (!m->unit)
 572                 return -ESRCH;
 573
 574         if (who == KILL_LEADER) /* If we shall simply kill the leader, do so directly */
 575                 return RET_NERRNO(kill(m->leader, signo));
 576
 577         /* Otherwise, make PID 1 do it for us, for the entire cgroup */
 578         return manager_kill_unit(m->manager, m->unit, signo, NULL);
 579 }
 580
 581 int machine_openpt(Machine *m, int flags, char **ret_slave) {
 582         assert(m);
 583
 584         switch (m->class) {
 585
 586         case MACHINE_HOST:
 587
 588                 return openpt_allocate(flags, ret_slave);
 589
 590         case MACHINE_CONTAINER:
 591                 if (m->leader <= 0)
 592                         return -EINVAL;
 593
 594                 return openpt_allocate_in_namespace(m->leader, flags, ret_slave);
 595
 596         default:
 597                 return -EOPNOTSUPP;
 598         }
 599 }
 600
 601 int machine_open_terminal(Machine *m, const char *path, int mode) {
 602         assert(m);
 603
 604         switch (m->class) {
 605
 606         case MACHINE_HOST:
 607                 return open_terminal(path, mode);
 608
 609         case MACHINE_CONTAINER:
 610                 if (m->leader <= 0)
 611                         return -EINVAL;
 612
 613                 return open_terminal_in_namespace(m->leader, path, mode);
 614
 615         default:
 616                 return -EOPNOTSUPP;
 617         }
 618 }
 619
 620 void machine_release_unit(Machine *m) {
 621         assert(m);
 622
 623         if (!m->unit)
 624                 return;
 625
 626         if (m->referenced) {
 627                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 628                 int r;
 629
 630                 r = manager_unref_unit(m->manager, m->unit, &error);
 631                 if (r < 0)
 632                         log_warning_errno(r, "Failed to drop reference to machine scope, ignoring: %s",
 633                                           bus_error_message(&error, r));
 634
 635                 m->referenced = false;
 636         }
 637
 638         (void) hashmap_remove(m->manager->machine_units, m->unit);
 639         m->unit = mfree(m->unit);
 640 }
 641
 642 int machine_get_uid_shift(Machine *m, uid_t *ret) {
 643         char p[STRLEN("/proc//uid_map") + DECIMAL_STR_MAX(pid_t) + 1];
 644         uid_t uid_base, uid_shift, uid_range;
 645         gid_t gid_base, gid_shift, gid_range;
 646         _cleanup_fclose_ FILE *f = NULL;
 647         int k, r;
 648
 649         assert(m);
 650         assert(ret);
 651
 652         /* Return the base UID/GID of the specified machine. Note that this only works for containers with simple
 653          * mappings. In most cases setups should be simple like this, and administrators should only care about the
 654          * basic offset a container has relative to the host. This is what this function exposes.
 655          *
 656          * If we encounter any more complex mappings we politely refuse this with ENXIO. */
 657
 658         if (m->class == MACHINE_HOST) {
 659                 *ret = 0;
 660                 return 0;
 661         }
 662
 663         if (m->class != MACHINE_CONTAINER)
 664                 return -EOPNOTSUPP;
 665
 666         xsprintf(p, "/proc/" PID_FMT "/uid_map", m->leader);
 667         f = fopen(p, "re");
 668         if (!f) {
 669                 if (errno == ENOENT) {
 670                         /* If the file doesn't exist, user namespacing is off in the kernel, return a zero mapping hence. */
 671                         *ret = 0;
 672                         return 0;
 673                 }
 674
 675                 return -errno;
 676         }
 677
 678         /* Read the first line. There's at least one. */
 679         errno = 0;
 680         k = fscanf(f, UID_FMT " " UID_FMT " " UID_FMT "\n", &uid_base, &uid_shift, &uid_range);
 681         if (k != 3) {
 682                 if (ferror(f))
 683                         return errno_or_else(EIO);
 684
 685                 return -EBADMSG;
 686         }
 687
 688         /* Not a mapping starting at 0? Then it's a complex mapping we can't expose here. */
 689         if (uid_base != 0)
 690                 return -ENXIO;
 691         /* Insist that at least the nobody user is mapped, everything else is weird, and hence complex, and we don't support it */
 692         if (uid_range < UID_NOBODY)
 693                 return -ENXIO;
 694
 695         /* If there's more than one line, then we don't support this mapping. */
 696         r = safe_fgetc(f, NULL);
 697         if (r < 0)
 698                 return r;
 699         if (r != 0) /* Insist on EOF */
 700                 return -ENXIO;
 701
 702         fclose(f);
 703
 704         xsprintf(p, "/proc/" PID_FMT "/gid_map", m->leader);
 705         f = fopen(p, "re");
 706         if (!f)
 707                 return -errno;
 708
 709         /* Read the first line. There's at least one. */
 710         errno = 0;
 711         k = fscanf(f, GID_FMT " " GID_FMT " " GID_FMT "\n", &gid_base, &gid_shift, &gid_range);
 712         if (k != 3) {
 713                 if (ferror(f))
 714                         return errno_or_else(EIO);
 715
 716                 return -EBADMSG;
 717         }
 718
 719         /* If there's more than one line, then we don't support this file. */
 720         r = safe_fgetc(f, NULL);
 721         if (r < 0)
 722                 return r;
 723         if (r != 0) /* Insist on EOF */
 724                 return -ENXIO;
 725
 726         /* If the UID and GID mapping doesn't match, we don't support this mapping. */
 727         if (uid_base != (uid_t) gid_base)
 728                 return -ENXIO;
 729         if (uid_shift != (uid_t) gid_shift)
 730                 return -ENXIO;
 731         if (uid_range != (uid_t) gid_range)
 732                 return -ENXIO;
 733
 734         *ret = uid_shift;
 735         return 0;
 736 }
 737
 738 static int machine_owns_uid_internal(
 739                 Machine *machine,
 740                 const char *map_file, /* "uid_map" or "gid_map" */
 741                 uid_t uid,
 742                 uid_t *ret_internal_uid) {
 743
 744         _cleanup_fclose_ FILE *f = NULL;
 745         const char *p;
 746
 747         /* This is a generic implementation for both uids and gids, under the assumptions they have the same types and semantics. */
 748         assert_cc(sizeof(uid_t) == sizeof(gid_t));
 749
 750         assert(machine);
 751
 752         /* Checks if the specified host UID is owned by the machine, and returns the UID it maps to
 753          * internally in the machine */
 754
 755         if (machine->class != MACHINE_CONTAINER)
 756                 goto negative;
 757
 758         p = procfs_file_alloca(machine->leader, map_file);
 759         f = fopen(p, "re");
 760         if (!f) {
 761                 log_debug_errno(errno, "Failed to open %s, ignoring.", p);
 762                 goto negative;
 763         }
 764
 765         for (;;) {
 766                 uid_t uid_base, uid_shift, uid_range, converted;
 767                 int k;
 768
 769                 errno = 0;
 770                 k = fscanf(f, UID_FMT " " UID_FMT " " UID_FMT, &uid_base, &uid_shift, &uid_range);
 771                 if (k < 0 && feof(f))
 772                         break;
 773                 if (k != 3) {
 774                         if (ferror(f))
 775                                 return errno_or_else(EIO);
 776
 777                         return -EIO;
 778                 }
 779
 780                 /* The private user namespace is disabled, ignoring. */
 781                 if (uid_shift == 0)
 782                         continue;
 783
 784                 if (uid < uid_shift || uid >= uid_shift + uid_range)
 785                         continue;
 786
 787                 converted = (uid - uid_shift + uid_base);
 788                 if (!uid_is_valid(converted))
 789                         return -EINVAL;
 790
 791                 if (ret_internal_uid)
 792                         *ret_internal_uid = converted;
 793
 794                 return true;
 795         }
 796
 797 negative:
 798         if (ret_internal_uid)
 799                 *ret_internal_uid = UID_INVALID;
 800
 801         return false;
 802 }
 803
 804 int machine_owns_uid(Machine *machine, uid_t uid, uid_t *ret_internal_uid) {
 805         return machine_owns_uid_internal(machine, "uid_map", uid, ret_internal_uid);
 806 }
 807
 808 int machine_owns_gid(Machine *machine, gid_t gid, gid_t *ret_internal_gid) {
 809         return machine_owns_uid_internal(machine, "gid_map", (uid_t) gid, (uid_t*) ret_internal_gid);
 810 }
 811
 812 static int machine_translate_uid_internal(
 813                 Machine *machine,
 814                 const char *map_file, /* "uid_map" or "gid_map" */
 815                 uid_t uid,
 816                 uid_t *ret_host_uid) {
 817
 818         _cleanup_fclose_ FILE *f = NULL;
 819         const char *p;
 820
 821         /* This is a generic implementation for both uids and gids, under the assumptions they have the same types and semantics. */
 822         assert_cc(sizeof(uid_t) == sizeof(gid_t));
 823
 824         assert(machine);
 825         assert(uid_is_valid(uid));
 826
 827         if (machine->class != MACHINE_CONTAINER)
 828                 return -ESRCH;
 829
 830         /* Translates a machine UID into a host UID */
 831
 832         p = procfs_file_alloca(machine->leader, map_file);
 833         f = fopen(p, "re");
 834         if (!f)
 835                 return -errno;
 836
 837         for (;;) {
 838                 uid_t uid_base, uid_shift, uid_range, converted;
 839                 int k;
 840
 841                 errno = 0;
 842                 k = fscanf(f, UID_FMT " " UID_FMT " " UID_FMT, &uid_base, &uid_shift, &uid_range);
 843                 if (k < 0 && feof(f))
 844                         break;
 845                 if (k != 3) {
 846                         if (ferror(f))
 847                                 return errno_or_else(EIO);
 848
 849                         return -EIO;
 850                 }
 851
 852                 if (uid < uid_base || uid >= uid_base + uid_range)
 853                         continue;
 854
 855                 converted = uid - uid_base + uid_shift;
 856                 if (!uid_is_valid(converted))
 857                         return -EINVAL;
 858
 859                 if (ret_host_uid)
 860                         *ret_host_uid = converted;
 861                 return 0;
 862         }
 863
 864         return -ESRCH;
 865 }
 866
 867 int machine_translate_uid(Machine *machine, gid_t uid, gid_t *ret_host_uid) {
 868         return machine_translate_uid_internal(machine, "uid_map", uid, ret_host_uid);
 869 }
 870
 871 int machine_translate_gid(Machine *machine, gid_t gid, gid_t *ret_host_gid) {
 872         return machine_translate_uid_internal(machine, "gid_map", (uid_t) gid, (uid_t*) ret_host_gid);
 873 }
 874
 875 static const char* const machine_class_table[_MACHINE_CLASS_MAX] = {
 876         [MACHINE_CONTAINER] = "container",
 877         [MACHINE_VM] = "vm",
 878         [MACHINE_HOST] = "host",
 879 };
 880
 881 DEFINE_STRING_TABLE_LOOKUP(machine_class, MachineClass);
 882
 883 static const char* const machine_state_table[_MACHINE_STATE_MAX] = {
 884         [MACHINE_OPENING] = "opening",
 885         [MACHINE_RUNNING] = "running",
 886         [MACHINE_CLOSING] = "closing"
 887 };
 888
 889 DEFINE_STRING_TABLE_LOOKUP(machine_state, MachineState);
 890
 891 static const char* const kill_who_table[_KILL_WHO_MAX] = {
 892         [KILL_LEADER] = "leader",
 893         [KILL_ALL] = "all"
 894 };
 895
 896 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);