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-unit-util.h"
  13 #include "bus-util.h"
  14 #include "env-file.h"
  15 #include "errno-util.h"
  16 #include "escape.h"
  17 #include "extract-word.h"
  18 #include "fd-util.h"
  19 #include "fileio.h"
  20 #include "format-util.h"
  21 #include "fs-util.h"
  22 #include "hashmap.h"
  23 #include "machine-dbus.h"
  24 #include "machine.h"
  25 #include "mkdir-label.h"
  26 #include "parse-util.h"
  27 #include "path-util.h"
  28 #include "process-util.h"
  29 #include "serialize.h"
  30 #include "socket-util.h"
  31 #include "special.h"
  32 #include "stdio-util.h"
  33 #include "string-table.h"
  34 #include "string-util.h"
  35 #include "terminal-util.h"
  36 #include "tmpfile-util.h"
  37 #include "uid-range.h"
  38 #include "unit-name.h"
  39 #include "user-util.h"
  40
  41 int machine_new(MachineClass class, const char *name, Machine **ret) {
  42         _cleanup_(machine_freep) Machine *m = NULL;
  43
  44         assert(class < _MACHINE_CLASS_MAX);
  45         assert(ret);
  46
  47         /* Passing class == _MACHINE_CLASS_INVALID here is fine. It
  48          * means as much as "we don't know yet", and that we'll figure
  49          * it out later when loading the state file. */
  50
  51         m = new(Machine, 1);
  52         if (!m)
  53                 return -ENOMEM;
  54
  55         *m = (Machine) {
  56                 .leader = PIDREF_NULL,
  57                 .vsock_cid = VMADDR_CID_ANY,
  58         };
  59
  60         if (name) {
  61                 m->name = strdup(name);
  62                 if (!m->name)
  63                         return -ENOMEM;
  64         }
  65
  66         m->class = class;
  67
  68         *ret = TAKE_PTR(m);
  69         return 0;
  70 }
  71
  72 int machine_link(Manager *manager, Machine *machine) {
  73         int r;
  74
  75         assert(manager);
  76         assert(machine);
  77
  78         if (machine->manager)
  79                 return -EEXIST;
  80         if (!machine->name)
  81                 return -EINVAL;
  82
  83         if (machine->class != MACHINE_HOST) {
  84                 char *temp = path_join("/run/systemd/machines", machine->name);
  85                 if (!temp)
  86                         return -ENOMEM;
  87
  88                 free_and_replace(machine->state_file, temp);
  89         }
  90
  91         r = hashmap_put(manager->machines, machine->name, machine);
  92         if (r < 0)
  93                 return r;
  94
  95         machine->manager = manager;
  96
  97         return 0;
  98 }
  99
 100 Machine* machine_free(Machine *m) {
 101         if (!m)
 102                 return NULL;
 103
 104         while (m->operations)
 105                 operation_free(m->operations);
 106
 107         if (m->in_gc_queue) {
 108                 assert(m->manager);
 109                 LIST_REMOVE(gc_queue, m->manager->machine_gc_queue, m);
 110         }
 111
 112         if (m->manager) {
 113                 machine_release_unit(m);
 114
 115                 (void) hashmap_remove(m->manager->machines, m->name);
 116
 117                 if (m->manager->host_machine == m)
 118                         m->manager->host_machine = NULL;
 119         }
 120
 121         if (pidref_is_set(&m->leader)) {
 122                 if (m->manager)
 123                         (void) hashmap_remove_value(m->manager->machine_leaders, PID_TO_PTR(m->leader.pid), m);
 124                 pidref_done(&m->leader);
 125         }
 126
 127         sd_bus_message_unref(m->create_message);
 128
 129         free(m->name);
 130         free(m->scope_job);
 131         free(m->state_file);
 132         free(m->service);
 133         free(m->root_directory);
 134         free(m->netif);
 135         free(m->ssh_address);
 136         free(m->ssh_private_key_path);
 137         return mfree(m);
 138 }
 139
 140 int machine_save(Machine *m) {
 141         _cleanup_(unlink_and_freep) char *temp_path = NULL;
 142         _cleanup_fclose_ FILE *f = NULL;
 143         int r;
 144
 145         assert(m);
 146
 147         if (!m->state_file)
 148                 return 0;
 149
 150         if (!m->started)
 151                 return 0;
 152
 153         r = mkdir_safe_label("/run/systemd/machines", 0755, 0, 0, MKDIR_WARN_MODE);
 154         if (r < 0)
 155                 goto fail;
 156
 157         r = fopen_temporary(m->state_file, &f, &temp_path);
 158         if (r < 0)
 159                 goto fail;
 160
 161         (void) fchmod(fileno(f), 0644);
 162
 163         fprintf(f,
 164                 "# This is private data. Do not parse.\n"
 165                 "NAME=%s\n",
 166                 m->name);
 167
 168         if (m->unit) {
 169                 _cleanup_free_ char *escaped = NULL;
 170
 171                 escaped = cescape(m->unit);
 172                 if (!escaped) {
 173                         r = -ENOMEM;
 174                         goto fail;
 175                 }
 176
 177                 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 */
 178         }
 179
 180         if (m->scope_job)
 181                 fprintf(f, "SCOPE_JOB=%s\n", m->scope_job);
 182
 183         if (m->service) {
 184                 _cleanup_free_ char *escaped = NULL;
 185
 186                 escaped = cescape(m->service);
 187                 if (!escaped) {
 188                         r = -ENOMEM;
 189                         goto fail;
 190                 }
 191                 fprintf(f, "SERVICE=%s\n", escaped);
 192         }
 193
 194         if (m->root_directory) {
 195                 _cleanup_free_ char *escaped = NULL;
 196
 197                 escaped = cescape(m->root_directory);
 198                 if (!escaped) {
 199                         r = -ENOMEM;
 200                         goto fail;
 201                 }
 202                 fprintf(f, "ROOT=%s\n", escaped);
 203         }
 204
 205         if (!sd_id128_is_null(m->id))
 206                 fprintf(f, "ID=" SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(m->id));
 207
 208         if (pidref_is_set(&m->leader))
 209                 fprintf(f, "LEADER="PID_FMT"\n", m->leader.pid);
 210
 211         if (m->class != _MACHINE_CLASS_INVALID)
 212                 fprintf(f, "CLASS=%s\n", machine_class_to_string(m->class));
 213
 214         if (dual_timestamp_is_set(&m->timestamp))
 215                 fprintf(f,
 216                         "REALTIME="USEC_FMT"\n"
 217                         "MONOTONIC="USEC_FMT"\n",
 218                         m->timestamp.realtime,
 219                         m->timestamp.monotonic);
 220
 221         if (m->n_netif > 0) {
 222                 size_t i;
 223
 224                 fputs("NETIF=", f);
 225
 226                 for (i = 0; i < m->n_netif; i++) {
 227                         if (i != 0)
 228                                 fputc(' ', f);
 229
 230                         fprintf(f, "%i", m->netif[i]);
 231                 }
 232
 233                 fputc('\n', f);
 234         }
 235
 236         r = fflush_and_check(f);
 237         if (r < 0)
 238                 goto fail;
 239
 240         if (rename(temp_path, m->state_file) < 0) {
 241                 r = -errno;
 242                 goto fail;
 243         }
 244
 245         temp_path = mfree(temp_path);
 246
 247         if (m->unit) {
 248                 char *sl;
 249
 250                 /* Create a symlink from the unit name to the machine
 251                  * name, so that we can quickly find the machine for
 252                  * each given unit. Ignore error. */
 253                 sl = strjoina("/run/systemd/machines/unit:", m->unit);
 254                 (void) symlink(m->name, sl);
 255         }
 256
 257         return 0;
 258
 259 fail:
 260         (void) unlink(m->state_file);
 261
 262         return log_error_errno(r, "Failed to save machine data %s: %m", m->state_file);
 263 }
 264
 265 static void machine_unlink(Machine *m) {
 266         assert(m);
 267
 268         if (m->unit) {
 269                 char *sl;
 270
 271                 sl = strjoina("/run/systemd/machines/unit:", m->unit);
 272                 (void) unlink(sl);
 273         }
 274
 275         if (m->state_file)
 276                 (void) unlink(m->state_file);
 277 }
 278
 279 int machine_load(Machine *m) {
 280         _cleanup_free_ char *realtime = NULL, *monotonic = NULL, *id = NULL, *leader = NULL, *class = NULL, *netif = NULL;
 281         int r;
 282
 283         assert(m);
 284
 285         if (!m->state_file)
 286                 return 0;
 287
 288         r = parse_env_file(NULL, m->state_file,
 289                            "SCOPE",     &m->unit,
 290                            "SCOPE_JOB", &m->scope_job,
 291                            "SERVICE",   &m->service,
 292                            "ROOT",      &m->root_directory,
 293                            "ID",        &id,
 294                            "LEADER",    &leader,
 295                            "CLASS",     &class,
 296                            "REALTIME",  &realtime,
 297                            "MONOTONIC", &monotonic,
 298                            "NETIF",     &netif);
 299         if (r == -ENOENT)
 300                 return 0;
 301         if (r < 0)
 302                 return log_error_errno(r, "Failed to read %s: %m", m->state_file);
 303
 304         if (id)
 305                 (void) sd_id128_from_string(id, &m->id);
 306
 307         if (leader) {
 308                 pidref_done(&m->leader);
 309                 r = pidref_set_pidstr(&m->leader, leader);
 310                 if (r < 0)
 311                         log_debug_errno(r, "Failed to set leader PID to '%s', ignoring: %m", leader);
 312         }
 313
 314         if (class) {
 315                 MachineClass c;
 316
 317                 c = machine_class_from_string(class);
 318                 if (c >= 0)
 319                         m->class = c;
 320         }
 321
 322         if (realtime)
 323                 (void) deserialize_usec(realtime, &m->timestamp.realtime);
 324         if (monotonic)
 325                 (void) deserialize_usec(monotonic, &m->timestamp.monotonic);
 326
 327         if (netif) {
 328                 _cleanup_free_ int *ni = NULL;
 329                 size_t nr = 0;
 330                 const char *p;
 331
 332                 p = netif;
 333                 for (;;) {
 334                         _cleanup_free_ char *word = NULL;
 335
 336                         r = extract_first_word(&p, &word, NULL, 0);
 337                         if (r == 0)
 338                                 break;
 339                         if (r == -ENOMEM)
 340                                 return log_oom();
 341                         if (r < 0) {
 342                                 log_warning_errno(r, "Failed to parse NETIF: %s", netif);
 343                                 break;
 344                         }
 345
 346                         r = parse_ifindex(word);
 347                         if (r < 0)
 348                                 continue;
 349
 350                         if (!GREEDY_REALLOC(ni, nr + 1))
 351                                 return log_oom();
 352
 353                         ni[nr++] = r;
 354                 }
 355
 356                 free_and_replace(m->netif, ni);
 357                 m->n_netif = nr;
 358         }
 359
 360         return r;
 361 }
 362
 363 static int machine_start_scope(
 364                 Machine *machine,
 365                 bool allow_pidfd,
 366                 sd_bus_message *more_properties,
 367                 sd_bus_error *error) {
 368
 369         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *reply = NULL;
 370         _cleanup_(sd_bus_error_free) sd_bus_error e = SD_BUS_ERROR_NULL;
 371         _cleanup_free_ char *escaped = NULL, *unit = NULL;
 372         const char *description;
 373         int r;
 374
 375         assert(machine);
 376         assert(pidref_is_set(&machine->leader));
 377         assert(!machine->unit);
 378
 379         escaped = unit_name_escape(machine->name);
 380         if (!escaped)
 381                 return log_oom();
 382
 383         unit = strjoin("machine-", escaped, ".scope");
 384         if (!unit)
 385                 return log_oom();
 386
 387         r = bus_message_new_method_call(
 388                         machine->manager->bus,
 389                         &m,
 390                         bus_systemd_mgr,
 391                         "StartTransientUnit");
 392         if (r < 0)
 393                 return r;
 394
 395         r = sd_bus_message_append(m, "ss", unit, "fail");
 396         if (r < 0)
 397                 return r;
 398
 399         r = sd_bus_message_open_container(m, 'a', "(sv)");
 400         if (r < 0)
 401                 return r;
 402
 403         r = sd_bus_message_append(m, "(sv)", "Slice", "s", SPECIAL_MACHINE_SLICE);
 404         if (r < 0)
 405                 return r;
 406
 407         description = strjoina(machine->class == MACHINE_VM ? "Virtual Machine " : "Container ", machine->name);
 408         r = sd_bus_message_append(m, "(sv)", "Description", "s", description);
 409         if (r < 0)
 410                 return r;
 411
 412         r = bus_append_scope_pidref(m, &machine->leader, allow_pidfd);
 413         if (r < 0)
 414                 return r;
 415
 416         r = sd_bus_message_append(m, "(sv)(sv)(sv)(sv)",
 417                                   "Delegate", "b", 1,
 418                                   "CollectMode", "s", "inactive-or-failed",
 419                                   "AddRef", "b", 1,
 420                                   "TasksMax", "t", UINT64_C(16384));
 421         if (r < 0)
 422                 return r;
 423
 424         if (more_properties) {
 425                 r = sd_bus_message_copy(m, more_properties, true);
 426                 if (r < 0)
 427                         return r;
 428         }
 429
 430         r = sd_bus_message_close_container(m);
 431         if (r < 0)
 432                 return r;
 433
 434         r = sd_bus_message_append(m, "a(sa(sv))", 0);
 435         if (r < 0)
 436                 return r;
 437
 438         r = sd_bus_call(NULL, m, 0, &e, &reply);
 439         if (r < 0) {
 440                 /* If this failed with a property we couldn't write, this is quite likely because the server
 441                  * doesn't support PIDFDs yet, let's try without. */
 442                 if (allow_pidfd &&
 443                     sd_bus_error_has_names(&e, SD_BUS_ERROR_UNKNOWN_PROPERTY, SD_BUS_ERROR_PROPERTY_READ_ONLY))
 444                         return machine_start_scope(machine, /* allow_pidfd = */ false, more_properties, error);
 445
 446                 return sd_bus_error_move(error, &e);
 447         }
 448
 449         machine->unit = TAKE_PTR(unit);
 450         machine->referenced = true;
 451
 452         const char *job;
 453         r = sd_bus_message_read(reply, "o", &job);
 454         if (r < 0)
 455                 return r;
 456
 457         return free_and_strdup(&machine->scope_job, job);
 458 }
 459
 460 static int machine_ensure_scope(Machine *m, sd_bus_message *properties, sd_bus_error *error) {
 461         int r;
 462
 463         assert(m);
 464         assert(m->class != MACHINE_HOST);
 465
 466         if (!m->unit) {
 467                 r = machine_start_scope(m, /* allow_pidfd = */ true, properties, error);
 468                 if (r < 0)
 469                         return log_error_errno(r, "Failed to start machine scope: %s", bus_error_message(error, r));
 470         }
 471
 472         assert(m->unit);
 473         hashmap_put(m->manager->machine_units, m->unit, m);
 474
 475         return 0;
 476 }
 477
 478 int machine_start(Machine *m, sd_bus_message *properties, sd_bus_error *error) {
 479         int r;
 480
 481         assert(m);
 482
 483         if (!IN_SET(m->class, MACHINE_CONTAINER, MACHINE_VM))
 484                 return -EOPNOTSUPP;
 485
 486         if (m->started)
 487                 return 0;
 488
 489         r = hashmap_put(m->manager->machine_leaders, PID_TO_PTR(m->leader.pid), m);
 490         if (r < 0)
 491                 return r;
 492
 493         /* Create cgroup */
 494         r = machine_ensure_scope(m, properties, error);
 495         if (r < 0)
 496                 return r;
 497
 498         log_struct(LOG_INFO,
 499                    "MESSAGE_ID=" SD_MESSAGE_MACHINE_START_STR,
 500                    "NAME=%s", m->name,
 501                    "LEADER="PID_FMT, m->leader.pid,
 502                    LOG_MESSAGE("New machine %s.", m->name));
 503
 504         if (!dual_timestamp_is_set(&m->timestamp))
 505                 dual_timestamp_now(&m->timestamp);
 506
 507         m->started = true;
 508
 509         /* Save new machine data */
 510         machine_save(m);
 511
 512         machine_send_signal(m, true);
 513         (void) manager_enqueue_nscd_cache_flush(m->manager);
 514
 515         return 0;
 516 }
 517
 518 int machine_stop(Machine *m) {
 519         int r;
 520
 521         assert(m);
 522
 523         if (!IN_SET(m->class, MACHINE_CONTAINER, MACHINE_VM))
 524                 return -EOPNOTSUPP;
 525
 526         if (m->unit) {
 527                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 528                 char *job = NULL;
 529
 530                 r = manager_stop_unit(m->manager, m->unit, &error, &job);
 531                 if (r < 0)
 532                         return log_error_errno(r, "Failed to stop machine scope: %s", bus_error_message(&error, r));
 533
 534                 free_and_replace(m->scope_job, job);
 535         }
 536
 537         m->stopping = true;
 538
 539         machine_save(m);
 540         (void) manager_enqueue_nscd_cache_flush(m->manager);
 541
 542         return 0;
 543 }
 544
 545 int machine_finalize(Machine *m) {
 546         assert(m);
 547
 548         if (m->started) {
 549                 log_struct(LOG_INFO,
 550                            "MESSAGE_ID=" SD_MESSAGE_MACHINE_STOP_STR,
 551                            "NAME=%s", m->name,
 552                            "LEADER="PID_FMT, m->leader.pid,
 553                            LOG_MESSAGE("Machine %s terminated.", m->name));
 554
 555                 m->stopping = true; /* The machine is supposed to be going away. Don't try to kill it. */
 556         }
 557
 558         machine_unlink(m);
 559         machine_add_to_gc_queue(m);
 560
 561         if (m->started) {
 562                 machine_send_signal(m, false);
 563                 m->started = false;
 564         }
 565
 566         return 0;
 567 }
 568
 569 bool machine_may_gc(Machine *m, bool drop_not_started) {
 570         assert(m);
 571
 572         if (m->class == MACHINE_HOST)
 573                 return false;
 574
 575         if (drop_not_started && !m->started)
 576                 return true;
 577
 578         if (m->scope_job && manager_job_is_active(m->manager, m->scope_job))
 579                 return false;
 580
 581         if (m->unit && manager_unit_is_active(m->manager, m->unit))
 582                 return false;
 583
 584         return true;
 585 }
 586
 587 void machine_add_to_gc_queue(Machine *m) {
 588         assert(m);
 589
 590         if (m->in_gc_queue)
 591                 return;
 592
 593         LIST_PREPEND(gc_queue, m->manager->machine_gc_queue, m);
 594         m->in_gc_queue = true;
 595 }
 596
 597 MachineState machine_get_state(Machine *s) {
 598         assert(s);
 599
 600         if (s->class == MACHINE_HOST)
 601                 return MACHINE_RUNNING;
 602
 603         if (s->stopping)
 604                 return MACHINE_CLOSING;
 605
 606         if (s->scope_job)
 607                 return MACHINE_OPENING;
 608
 609         return MACHINE_RUNNING;
 610 }
 611
 612 int machine_kill(Machine *m, KillWho who, int signo) {
 613         assert(m);
 614
 615         if (!IN_SET(m->class, MACHINE_VM, MACHINE_CONTAINER))
 616                 return -EOPNOTSUPP;
 617
 618         if (!m->unit)
 619                 return -ESRCH;
 620
 621         if (who == KILL_LEADER) /* If we shall simply kill the leader, do so directly */
 622                 return pidref_kill(&m->leader, signo);
 623
 624         /* Otherwise, make PID 1 do it for us, for the entire cgroup */
 625         return manager_kill_unit(m->manager, m->unit, signo, NULL);
 626 }
 627
 628 int machine_openpt(Machine *m, int flags, char **ret_slave) {
 629         assert(m);
 630
 631         switch (m->class) {
 632
 633         case MACHINE_HOST:
 634                 return openpt_allocate(flags, ret_slave);
 635
 636         case MACHINE_CONTAINER:
 637                 if (!pidref_is_set(&m->leader))
 638                         return -EINVAL;
 639
 640                 return openpt_allocate_in_namespace(m->leader.pid, flags, ret_slave);
 641
 642         default:
 643                 return -EOPNOTSUPP;
 644         }
 645 }
 646
 647 int machine_open_terminal(Machine *m, const char *path, int mode) {
 648         assert(m);
 649
 650         switch (m->class) {
 651
 652         case MACHINE_HOST:
 653                 return open_terminal(path, mode);
 654
 655         case MACHINE_CONTAINER:
 656                 if (!pidref_is_set(&m->leader))
 657                         return -EINVAL;
 658
 659                 return open_terminal_in_namespace(m->leader.pid, path, mode);
 660
 661         default:
 662                 return -EOPNOTSUPP;
 663         }
 664 }
 665
 666 void machine_release_unit(Machine *m) {
 667         assert(m);
 668
 669         if (!m->unit)
 670                 return;
 671
 672         if (m->referenced) {
 673                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 674                 int r;
 675
 676                 r = manager_unref_unit(m->manager, m->unit, &error);
 677                 if (r < 0)
 678                         log_full_errno(ERRNO_IS_DISCONNECT(r) ? LOG_DEBUG : LOG_WARNING, r,
 679                                        "Failed to drop reference to machine scope, ignoring: %s",
 680                                        bus_error_message(&error, r));
 681
 682                 m->referenced = false;
 683         }
 684
 685         (void) hashmap_remove(m->manager->machine_units, m->unit);
 686         m->unit = mfree(m->unit);
 687 }
 688
 689 int machine_get_uid_shift(Machine *m, uid_t *ret) {
 690         char p[STRLEN("/proc//uid_map") + DECIMAL_STR_MAX(pid_t) + 1];
 691         uid_t uid_base, uid_shift, uid_range;
 692         gid_t gid_base, gid_shift, gid_range;
 693         _cleanup_fclose_ FILE *f = NULL;
 694         int r;
 695
 696         assert(m);
 697         assert(ret);
 698
 699         /* Return the base UID/GID of the specified machine. Note that this only works for containers with simple
 700          * mappings. In most cases setups should be simple like this, and administrators should only care about the
 701          * basic offset a container has relative to the host. This is what this function exposes.
 702          *
 703          * If we encounter any more complex mappings we politely refuse this with ENXIO. */
 704
 705         if (m->class == MACHINE_HOST) {
 706                 *ret = 0;
 707                 return 0;
 708         }
 709
 710         if (m->class != MACHINE_CONTAINER)
 711                 return -EOPNOTSUPP;
 712
 713         xsprintf(p, "/proc/" PID_FMT "/uid_map", m->leader.pid);
 714         f = fopen(p, "re");
 715         if (!f) {
 716                 if (errno == ENOENT) {
 717                         /* If the file doesn't exist, user namespacing is off in the kernel, return a zero mapping hence. */
 718                         *ret = 0;
 719                         return 0;
 720                 }
 721
 722                 return -errno;
 723         }
 724
 725         /* Read the first line. There's at least one. */
 726         r = uid_map_read_one(f, &uid_base, &uid_shift, &uid_range);
 727         if (r < 0)
 728                 return r;
 729
 730         /* Not a mapping starting at 0? Then it's a complex mapping we can't expose here. */
 731         if (uid_base != 0)
 732                 return -ENXIO;
 733         /* Insist that at least the nobody user is mapped, everything else is weird, and hence complex, and we don't support it */
 734         if (uid_range < UID_NOBODY)
 735                 return -ENXIO;
 736
 737         /* If there's more than one line, then we don't support this mapping. */
 738         r = safe_fgetc(f, NULL);
 739         if (r < 0)
 740                 return r;
 741         if (r != 0) /* Insist on EOF */
 742                 return -ENXIO;
 743
 744         fclose(f);
 745
 746         xsprintf(p, "/proc/" PID_FMT "/gid_map", m->leader.pid);
 747         f = fopen(p, "re");
 748         if (!f)
 749                 return -errno;
 750
 751         /* Read the first line. There's at least one. */
 752         errno = 0;
 753         r = fscanf(f, GID_FMT " " GID_FMT " " GID_FMT "\n", &gid_base, &gid_shift, &gid_range);
 754         if (r == EOF)
 755                 return errno_or_else(ENOMSG);
 756         assert(r >= 0);
 757         if (r != 3)
 758                 return -EBADMSG;
 759
 760         /* If there's more than one line, then we don't support this file. */
 761         r = safe_fgetc(f, NULL);
 762         if (r < 0)
 763                 return r;
 764         if (r != 0) /* Insist on EOF */
 765                 return -ENXIO;
 766
 767         /* If the UID and GID mapping doesn't match, we don't support this mapping. */
 768         if (uid_base != (uid_t) gid_base)
 769                 return -ENXIO;
 770         if (uid_shift != (uid_t) gid_shift)
 771                 return -ENXIO;
 772         if (uid_range != (uid_t) gid_range)
 773                 return -ENXIO;
 774
 775         *ret = uid_shift;
 776         return 0;
 777 }
 778
 779 static int machine_owns_uid_internal(
 780                 Machine *machine,
 781                 const char *map_file, /* "uid_map" or "gid_map" */
 782                 uid_t uid,
 783                 uid_t *ret_internal_uid) {
 784
 785         _cleanup_fclose_ FILE *f = NULL;
 786         const char *p;
 787         int r;
 788
 789         /* This is a generic implementation for both uids and gids, under the assumptions they have the same types and semantics. */
 790         assert_cc(sizeof(uid_t) == sizeof(gid_t));
 791
 792         assert(machine);
 793
 794         /* Checks if the specified host UID is owned by the machine, and returns the UID it maps to
 795          * internally in the machine */
 796
 797         if (machine->class != MACHINE_CONTAINER)
 798                 goto negative;
 799
 800         p = procfs_file_alloca(machine->leader.pid, map_file);
 801         f = fopen(p, "re");
 802         if (!f) {
 803                 log_debug_errno(errno, "Failed to open %s, ignoring.", p);
 804                 goto negative;
 805         }
 806
 807         for (;;) {
 808                 uid_t uid_base, uid_shift, uid_range, converted;
 809
 810                 r = uid_map_read_one(f, &uid_base, &uid_shift, &uid_range);
 811                 if (r == -ENOMSG)
 812                         break;
 813                 if (r < 0)
 814                         return r;
 815
 816                 /* The private user namespace is disabled, ignoring. */
 817                 if (uid_shift == 0)
 818                         continue;
 819
 820                 if (uid < uid_shift || uid >= uid_shift + uid_range)
 821                         continue;
 822
 823                 converted = (uid - uid_shift + uid_base);
 824                 if (!uid_is_valid(converted))
 825                         return -EINVAL;
 826
 827                 if (ret_internal_uid)
 828                         *ret_internal_uid = converted;
 829
 830                 return true;
 831         }
 832
 833 negative:
 834         if (ret_internal_uid)
 835                 *ret_internal_uid = UID_INVALID;
 836
 837         return false;
 838 }
 839
 840 int machine_owns_uid(Machine *machine, uid_t uid, uid_t *ret_internal_uid) {
 841         return machine_owns_uid_internal(machine, "uid_map", uid, ret_internal_uid);
 842 }
 843
 844 int machine_owns_gid(Machine *machine, gid_t gid, gid_t *ret_internal_gid) {
 845         return machine_owns_uid_internal(machine, "gid_map", (uid_t) gid, (uid_t*) ret_internal_gid);
 846 }
 847
 848 static int machine_translate_uid_internal(
 849                 Machine *machine,
 850                 const char *map_file, /* "uid_map" or "gid_map" */
 851                 uid_t uid,
 852                 uid_t *ret_host_uid) {
 853
 854         _cleanup_fclose_ FILE *f = NULL;
 855         const char *p;
 856         int r;
 857
 858         /* This is a generic implementation for both uids and gids, under the assumptions they have the same types and semantics. */
 859         assert_cc(sizeof(uid_t) == sizeof(gid_t));
 860
 861         assert(machine);
 862         assert(uid_is_valid(uid));
 863
 864         if (machine->class != MACHINE_CONTAINER)
 865                 return -ESRCH;
 866
 867         /* Translates a machine UID into a host UID */
 868
 869         p = procfs_file_alloca(machine->leader.pid, map_file);
 870         f = fopen(p, "re");
 871         if (!f)
 872                 return -errno;
 873
 874         for (;;) {
 875                 uid_t uid_base, uid_shift, uid_range, converted;
 876
 877                 r = uid_map_read_one(f, &uid_base, &uid_shift, &uid_range);
 878                 if (r == -ENOMSG)
 879                         break;
 880                 if (r < 0)
 881                         return r;
 882
 883                 if (uid < uid_base || uid >= uid_base + uid_range)
 884                         continue;
 885
 886                 converted = uid - uid_base + uid_shift;
 887                 if (!uid_is_valid(converted))
 888                         return -EINVAL;
 889
 890                 if (ret_host_uid)
 891                         *ret_host_uid = converted;
 892
 893                 return 0;
 894         }
 895
 896         return -ESRCH;
 897 }
 898
 899 int machine_translate_uid(Machine *machine, gid_t uid, gid_t *ret_host_uid) {
 900         return machine_translate_uid_internal(machine, "uid_map", uid, ret_host_uid);
 901 }
 902
 903 int machine_translate_gid(Machine *machine, gid_t gid, gid_t *ret_host_gid) {
 904         return machine_translate_uid_internal(machine, "gid_map", (uid_t) gid, (uid_t*) ret_host_gid);
 905 }
 906
 907 static const char* const machine_class_table[_MACHINE_CLASS_MAX] = {
 908         [MACHINE_CONTAINER] = "container",
 909         [MACHINE_VM] = "vm",
 910         [MACHINE_HOST] = "host",
 911 };
 912
 913 DEFINE_STRING_TABLE_LOOKUP(machine_class, MachineClass);
 914
 915 static const char* const machine_state_table[_MACHINE_STATE_MAX] = {
 916         [MACHINE_OPENING] = "opening",
 917         [MACHINE_RUNNING] = "running",
 918         [MACHINE_CLOSING] = "closing"
 919 };
 920
 921 DEFINE_STRING_TABLE_LOOKUP(machine_state, MachineState);
 922
 923 static const char* const kill_who_table[_KILL_WHO_MAX] = {
 924         [KILL_LEADER] = "leader",
 925         [KILL_ALL] = "all"
 926 };
 927
 928 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);