src/core/automount.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include <limits.h>
   6 #include <linux/auto_dev-ioctl.h>
   7 #include <linux/auto_fs4.h>
   8 #include <sys/epoll.h>
   9 #include <sys/mount.h>
  10 #include <sys/stat.h>
  11 #include <unistd.h>
  12
  13 #include "alloc-util.h"
  14 #include "async.h"
  15 #include "automount.h"
  16 #include "bus-error.h"
  17 #include "bus-util.h"
  18 #include "dbus-automount.h"
  19 #include "dbus-unit.h"
  20 #include "fd-util.h"
  21 #include "format-util.h"
  22 #include "io-util.h"
  23 #include "label.h"
  24 #include "mkdir.h"
  25 #include "mount-util.h"
  26 #include "mount.h"
  27 #include "mountpoint-util.h"
  28 #include "parse-util.h"
  29 #include "path-util.h"
  30 #include "process-util.h"
  31 #include "serialize.h"
  32 #include "special.h"
  33 #include "stdio-util.h"
  34 #include "string-table.h"
  35 #include "string-util.h"
  36 #include "unit-name.h"
  37 #include "unit.h"
  38
  39 static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {
  40         [AUTOMOUNT_DEAD] = UNIT_INACTIVE,
  41         [AUTOMOUNT_WAITING] = UNIT_ACTIVE,
  42         [AUTOMOUNT_RUNNING] = UNIT_ACTIVE,
  43         [AUTOMOUNT_FAILED] = UNIT_FAILED
  44 };
  45
  46 struct expire_data {
  47         int dev_autofs_fd;
  48         int ioctl_fd;
  49 };
  50
  51 static void expire_data_free(struct expire_data *data) {
  52         if (!data)
  53                 return;
  54
  55         safe_close(data->dev_autofs_fd);
  56         safe_close(data->ioctl_fd);
  57         free(data);
  58 }
  59
  60 DEFINE_TRIVIAL_CLEANUP_FUNC(struct expire_data*, expire_data_free);
  61
  62 static int open_dev_autofs(Manager *m);
  63 static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata);
  64 static int automount_start_expire(Automount *a);
  65 static void automount_stop_expire(Automount *a);
  66 static int automount_send_ready(Automount *a, Set *tokens, int status);
  67
  68 static void automount_init(Unit *u) {
  69         Automount *a = AUTOMOUNT(u);
  70
  71         assert(u);
  72         assert(u->load_state == UNIT_STUB);
  73
  74         a->pipe_fd = -1;
  75         a->directory_mode = 0755;
  76         UNIT(a)->ignore_on_isolate = true;
  77 }
  78
  79 static void unmount_autofs(Automount *a) {
  80         int r;
  81
  82         assert(a);
  83
  84         if (a->pipe_fd < 0)
  85                 return;
  86
  87         a->pipe_event_source = sd_event_source_unref(a->pipe_event_source);
  88         a->pipe_fd = safe_close(a->pipe_fd);
  89
  90         /* If we reload/reexecute things we keep the mount point around */
  91         if (!IN_SET(UNIT(a)->manager->objective, MANAGER_RELOAD, MANAGER_REEXECUTE)) {
  92
  93                 automount_send_ready(a, a->tokens, -EHOSTDOWN);
  94                 automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);
  95
  96                 if (a->where) {
  97                         r = repeat_unmount(a->where, MNT_DETACH);
  98                         if (r < 0)
  99                                 log_error_errno(r, "Failed to unmount: %m");
 100                 }
 101         }
 102 }
 103
 104 static void automount_done(Unit *u) {
 105         Automount *a = AUTOMOUNT(u);
 106
 107         assert(a);
 108
 109         unmount_autofs(a);
 110
 111         a->where = mfree(a->where);
 112
 113         a->tokens = set_free(a->tokens);
 114         a->expire_tokens = set_free(a->expire_tokens);
 115
 116         a->expire_event_source = sd_event_source_unref(a->expire_event_source);
 117 }
 118
 119 static int automount_add_trigger_dependencies(Automount *a) {
 120         Unit *x;
 121         int r;
 122
 123         assert(a);
 124
 125         r = unit_load_related_unit(UNIT(a), ".mount", &x);
 126         if (r < 0)
 127                 return r;
 128
 129         return unit_add_two_dependencies(UNIT(a), UNIT_BEFORE, UNIT_TRIGGERS, x, true, UNIT_DEPENDENCY_IMPLICIT);
 130 }
 131
 132 static int automount_add_mount_dependencies(Automount *a) {
 133         _cleanup_free_ char *parent = NULL;
 134
 135         assert(a);
 136
 137         parent = dirname_malloc(a->where);
 138         if (!parent)
 139                 return -ENOMEM;
 140
 141         return unit_require_mounts_for(UNIT(a), parent, UNIT_DEPENDENCY_IMPLICIT);
 142 }
 143
 144 static int automount_add_default_dependencies(Automount *a) {
 145         int r;
 146
 147         assert(a);
 148
 149         if (!UNIT(a)->default_dependencies)
 150                 return 0;
 151
 152         if (!MANAGER_IS_SYSTEM(UNIT(a)->manager))
 153                 return 0;
 154
 155         r = unit_add_dependency_by_name(UNIT(a), UNIT_BEFORE, SPECIAL_LOCAL_FS_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
 156         if (r < 0)
 157                 return r;
 158
 159         r = unit_add_dependency_by_name(UNIT(a), UNIT_AFTER, SPECIAL_LOCAL_FS_PRE_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
 160         if (r < 0)
 161                 return r;
 162
 163         r = unit_add_two_dependencies_by_name(UNIT(a), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
 164         if (r < 0)
 165                 return r;
 166
 167         return 0;
 168 }
 169
 170 static int automount_verify(Automount *a) {
 171         _cleanup_free_ char *e = NULL;
 172         int r;
 173
 174         assert(a);
 175         assert(UNIT(a)->load_state == UNIT_LOADED);
 176
 177         if (path_equal(a->where, "/")) {
 178                 log_unit_error(UNIT(a), "Cannot have an automount unit for the root directory. Refusing.");
 179                 return -ENOEXEC;
 180         }
 181
 182         r = unit_name_from_path(a->where, ".automount", &e);
 183         if (r < 0)
 184                 return log_unit_error_errno(UNIT(a), r, "Failed to generate unit name from path: %m");
 185
 186         if (!unit_has_name(UNIT(a), e)) {
 187                 log_unit_error(UNIT(a), "Where= setting doesn't match unit name. Refusing.");
 188                 return -ENOEXEC;
 189         }
 190
 191         return 0;
 192 }
 193
 194 static int automount_set_where(Automount *a) {
 195         int r;
 196
 197         assert(a);
 198
 199         if (a->where)
 200                 return 0;
 201
 202         r = unit_name_to_path(UNIT(a)->id, &a->where);
 203         if (r < 0)
 204                 return r;
 205
 206         path_simplify(a->where, false);
 207         return 1;
 208 }
 209
 210 static int automount_add_extras(Automount *a) {
 211         int r;
 212
 213         r = automount_set_where(a);
 214         if (r < 0)
 215                 return r;
 216
 217         r = automount_add_trigger_dependencies(a);
 218         if (r < 0)
 219                 return r;
 220
 221         r = automount_add_mount_dependencies(a);
 222         if (r < 0)
 223                 return r;
 224
 225         return automount_add_default_dependencies(a);
 226 }
 227
 228 static int automount_load(Unit *u) {
 229         Automount *a = AUTOMOUNT(u);
 230         int r;
 231
 232         assert(u);
 233         assert(u->load_state == UNIT_STUB);
 234
 235         /* Load a .automount file */
 236         r = unit_load_fragment_and_dropin(u, true);
 237         if (r < 0)
 238                 return r;
 239
 240         if (u->load_state != UNIT_LOADED)
 241                 return 0;
 242
 243         r = automount_add_extras(a);
 244         if (r < 0)
 245                 return r;
 246
 247         return automount_verify(a);
 248 }
 249
 250 static void automount_set_state(Automount *a, AutomountState state) {
 251         AutomountState old_state;
 252         assert(a);
 253
 254         if (a->state != state)
 255                 bus_unit_send_pending_change_signal(UNIT(a), false);
 256
 257         old_state = a->state;
 258         a->state = state;
 259
 260         if (state != AUTOMOUNT_RUNNING)
 261                 automount_stop_expire(a);
 262
 263         if (!IN_SET(state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING))
 264                 unmount_autofs(a);
 265
 266         if (state != old_state)
 267                 log_unit_debug(UNIT(a), "Changed %s -> %s", automount_state_to_string(old_state), automount_state_to_string(state));
 268
 269         unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state], 0);
 270 }
 271
 272 static int automount_coldplug(Unit *u) {
 273         Automount *a = AUTOMOUNT(u);
 274         int r;
 275
 276         assert(a);
 277         assert(a->state == AUTOMOUNT_DEAD);
 278
 279         if (a->deserialized_state == a->state)
 280                 return 0;
 281
 282         if (IN_SET(a->deserialized_state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING)) {
 283
 284                 r = automount_set_where(a);
 285                 if (r < 0)
 286                         return r;
 287
 288                 r = open_dev_autofs(u->manager);
 289                 if (r < 0)
 290                         return r;
 291
 292                 assert(a->pipe_fd >= 0);
 293
 294                 r = sd_event_add_io(u->manager->event, &a->pipe_event_source, a->pipe_fd, EPOLLIN, automount_dispatch_io, u);
 295                 if (r < 0)
 296                         return r;
 297
 298                 (void) sd_event_source_set_description(a->pipe_event_source, "automount-io");
 299                 if (a->deserialized_state == AUTOMOUNT_RUNNING) {
 300                         r = automount_start_expire(a);
 301                         if (r < 0)
 302                                 log_unit_warning_errno(UNIT(a), r, "Failed to start expiration timer, ignoring: %m");
 303                 }
 304
 305                 automount_set_state(a, a->deserialized_state);
 306         }
 307
 308         return 0;
 309 }
 310
 311 static void automount_dump(Unit *u, FILE *f, const char *prefix) {
 312         char time_string[FORMAT_TIMESPAN_MAX];
 313         Automount *a = AUTOMOUNT(u);
 314
 315         assert(a);
 316
 317         fprintf(f,
 318                 "%sAutomount State: %s\n"
 319                 "%sResult: %s\n"
 320                 "%sWhere: %s\n"
 321                 "%sDirectoryMode: %04o\n"
 322                 "%sTimeoutIdleUSec: %s\n",
 323                 prefix, automount_state_to_string(a->state),
 324                 prefix, automount_result_to_string(a->result),
 325                 prefix, a->where,
 326                 prefix, a->directory_mode,
 327                 prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, a->timeout_idle_usec, USEC_PER_SEC));
 328 }
 329
 330 static void automount_enter_dead(Automount *a, AutomountResult f) {
 331         assert(a);
 332
 333         if (a->result == AUTOMOUNT_SUCCESS)
 334                 a->result = f;
 335
 336         unit_log_result(UNIT(a), a->result == AUTOMOUNT_SUCCESS, automount_result_to_string(a->result));
 337         automount_set_state(a, a->result != AUTOMOUNT_SUCCESS ? AUTOMOUNT_FAILED : AUTOMOUNT_DEAD);
 338 }
 339
 340 static int open_dev_autofs(Manager *m) {
 341         struct autofs_dev_ioctl param;
 342
 343         assert(m);
 344
 345         if (m->dev_autofs_fd >= 0)
 346                 return m->dev_autofs_fd;
 347
 348         (void) label_fix("/dev/autofs", 0);
 349
 350         m->dev_autofs_fd = open("/dev/autofs", O_CLOEXEC|O_RDONLY);
 351         if (m->dev_autofs_fd < 0)
 352                 return log_error_errno(errno, "Failed to open /dev/autofs: %m");
 353
 354         init_autofs_dev_ioctl(&param);
 355         if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, &param) < 0) {
 356                 m->dev_autofs_fd = safe_close(m->dev_autofs_fd);
 357                 return -errno;
 358         }
 359
 360         log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
 361
 362         return m->dev_autofs_fd;
 363 }
 364
 365 static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
 366         struct autofs_dev_ioctl *param;
 367         size_t l;
 368
 369         assert(dev_autofs_fd >= 0);
 370         assert(where);
 371
 372         l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
 373         param = alloca(l);
 374
 375         init_autofs_dev_ioctl(param);
 376         param->size = l;
 377         param->ioctlfd = -1;
 378         param->openmount.devid = devid;
 379         strcpy(param->path, where);
 380
 381         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0)
 382                 return -errno;
 383
 384         if (param->ioctlfd < 0)
 385                 return -EIO;
 386
 387         (void) fd_cloexec(param->ioctlfd, true);
 388         return param->ioctlfd;
 389 }
 390
 391 static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
 392         uint32_t major, minor;
 393         struct autofs_dev_ioctl param;
 394
 395         assert(dev_autofs_fd >= 0);
 396         assert(ioctl_fd >= 0);
 397
 398         init_autofs_dev_ioctl(&param);
 399         param.ioctlfd = ioctl_fd;
 400
 401         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, &param) < 0)
 402                 return -errno;
 403
 404         major = param.protover.version;
 405
 406         init_autofs_dev_ioctl(&param);
 407         param.ioctlfd = ioctl_fd;
 408
 409         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, &param) < 0)
 410                 return -errno;
 411
 412         minor = param.protosubver.sub_version;
 413
 414         log_debug("Autofs protocol version %i.%i", major, minor);
 415         return 0;
 416 }
 417
 418 static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, usec_t usec) {
 419         struct autofs_dev_ioctl param;
 420
 421         assert(dev_autofs_fd >= 0);
 422         assert(ioctl_fd >= 0);
 423
 424         init_autofs_dev_ioctl(&param);
 425         param.ioctlfd = ioctl_fd;
 426
 427         if (usec == USEC_INFINITY)
 428                 param.timeout.timeout = 0;
 429         else
 430                 /* Convert to seconds, rounding up. */
 431                 param.timeout.timeout = DIV_ROUND_UP(usec, USEC_PER_SEC);
 432
 433         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)
 434                 return -errno;
 435
 436         return 0;
 437 }
 438
 439 static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
 440         struct autofs_dev_ioctl param;
 441
 442         assert(dev_autofs_fd >= 0);
 443         assert(ioctl_fd >= 0);
 444
 445         init_autofs_dev_ioctl(&param);
 446         param.ioctlfd = ioctl_fd;
 447
 448         if (status != 0) {
 449                 param.fail.token = token;
 450                 param.fail.status = status;
 451         } else
 452                 param.ready.token = token;
 453
 454         if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, &param) < 0)
 455                 return -errno;
 456
 457         return 0;
 458 }
 459
 460 static int automount_send_ready(Automount *a, Set *tokens, int status) {
 461         _cleanup_close_ int ioctl_fd = -1;
 462         unsigned token;
 463         int r;
 464
 465         assert(a);
 466         assert(status <= 0);
 467
 468         if (set_isempty(tokens))
 469                 return 0;
 470
 471         ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);
 472         if (ioctl_fd < 0)
 473                 return ioctl_fd;
 474
 475         if (status != 0)
 476                 log_unit_debug_errno(UNIT(a), status, "Sending failure: %m");
 477         else
 478                 log_unit_debug(UNIT(a), "Sending success.");
 479
 480         r = 0;
 481
 482         /* Autofs thankfully does not hand out 0 as a token */
 483         while ((token = PTR_TO_UINT(set_steal_first(tokens)))) {
 484                 int k;
 485
 486                 /* Autofs fun fact:
 487                  *
 488                  * if you pass a positive status code here, kernels
 489                  * prior to 4.12 will freeze! Yay! */
 490
 491                 k = autofs_send_ready(UNIT(a)->manager->dev_autofs_fd,
 492                                       ioctl_fd,
 493                                       token,
 494                                       status);
 495                 if (k < 0)
 496                         r = k;
 497         }
 498
 499         return r;
 500 }
 501
 502 static void automount_trigger_notify(Unit *u, Unit *other) {
 503         Automount *a = AUTOMOUNT(u);
 504         int r;
 505
 506         assert(a);
 507         assert(other);
 508
 509         /* Filter out invocations with bogus state */
 510         if (other->load_state != UNIT_LOADED || other->type != UNIT_MOUNT)
 511                 return;
 512
 513         /* Don't propagate state changes from the mount if we are already down */
 514         if (!IN_SET(a->state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING))
 515                 return;
 516
 517         /* Propagate start limit hit state */
 518         if (other->start_limit_hit) {
 519                 automount_enter_dead(a, AUTOMOUNT_FAILURE_MOUNT_START_LIMIT_HIT);
 520                 return;
 521         }
 522
 523         /* Don't propagate anything if there's still a job queued */
 524         if (other->job)
 525                 return;
 526
 527         /* The mount is successfully established */
 528         if (IN_SET(MOUNT(other)->state, MOUNT_MOUNTED, MOUNT_REMOUNTING)) {
 529                 (void) automount_send_ready(a, a->tokens, 0);
 530
 531                 r = automount_start_expire(a);
 532                 if (r < 0)
 533                         log_unit_warning_errno(UNIT(a), r, "Failed to start expiration timer, ignoring: %m");
 534
 535                 automount_set_state(a, AUTOMOUNT_RUNNING);
 536         }
 537
 538         if (IN_SET(MOUNT(other)->state,
 539                    MOUNT_MOUNTING, MOUNT_MOUNTING_DONE,
 540                    MOUNT_MOUNTED, MOUNT_REMOUNTING,
 541                    MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL,
 542                    MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL,
 543                    MOUNT_FAILED)) {
 544
 545                 (void) automount_send_ready(a, a->expire_tokens, -ENODEV);
 546         }
 547
 548         if (MOUNT(other)->state == MOUNT_DEAD)
 549                 (void) automount_send_ready(a, a->expire_tokens, 0);
 550
 551         /* The mount is in some unhappy state now, let's unfreeze any waiting clients */
 552         if (IN_SET(MOUNT(other)->state,
 553                    MOUNT_DEAD, MOUNT_UNMOUNTING,
 554                    MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL,
 555                    MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL,
 556                    MOUNT_FAILED)) {
 557
 558                 (void) automount_send_ready(a, a->tokens, -ENODEV);
 559
 560                 automount_set_state(a, AUTOMOUNT_WAITING);
 561         }
 562 }
 563
 564 static void automount_enter_waiting(Automount *a) {
 565         _cleanup_close_ int ioctl_fd = -1;
 566         int p[2] = { -1, -1 };
 567         char name[STRLEN("systemd-") + DECIMAL_STR_MAX(pid_t) + 1];
 568         char options[STRLEN("fd=,pgrp=,minproto=5,maxproto=5,direct")
 569                      + DECIMAL_STR_MAX(int) + DECIMAL_STR_MAX(gid_t) + 1];
 570         bool mounted = false;
 571         int r, dev_autofs_fd;
 572         struct stat st;
 573
 574         assert(a);
 575         assert(a->pipe_fd < 0);
 576         assert(a->where);
 577
 578         set_clear(a->tokens);
 579
 580         r = unit_fail_if_noncanonical(UNIT(a), a->where);
 581         if (r < 0)
 582                 goto fail;
 583
 584         (void) mkdir_p_label(a->where, a->directory_mode);
 585
 586         unit_warn_if_dir_nonempty(UNIT(a), a->where);
 587
 588         dev_autofs_fd = open_dev_autofs(UNIT(a)->manager);
 589         if (dev_autofs_fd < 0) {
 590                 r = dev_autofs_fd;
 591                 goto fail;
 592         }
 593
 594         if (pipe2(p, O_CLOEXEC) < 0) {
 595                 r = -errno;
 596                 goto fail;
 597         }
 598         r = fd_nonblock(p[0], true);
 599         if (r < 0)
 600                 goto fail;
 601
 602         xsprintf(options, "fd=%i,pgrp="PID_FMT",minproto=5,maxproto=5,direct", p[1], getpgrp());
 603         xsprintf(name, "systemd-"PID_FMT, getpid_cached());
 604         if (mount(name, a->where, "autofs", 0, options) < 0) {
 605                 r = -errno;
 606                 goto fail;
 607         }
 608
 609         mounted = true;
 610
 611         p[1] = safe_close(p[1]);
 612
 613         if (stat(a->where, &st) < 0) {
 614                 r = -errno;
 615                 goto fail;
 616         }
 617
 618         ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev);
 619         if (ioctl_fd < 0) {
 620                 r = ioctl_fd;
 621                 goto fail;
 622         }
 623
 624         r = autofs_protocol(dev_autofs_fd, ioctl_fd);
 625         if (r < 0)
 626                 goto fail;
 627
 628         r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, a->timeout_idle_usec);
 629         if (r < 0)
 630                 goto fail;
 631
 632         r = sd_event_add_io(UNIT(a)->manager->event, &a->pipe_event_source, p[0], EPOLLIN, automount_dispatch_io, a);
 633         if (r < 0)
 634                 goto fail;
 635
 636         (void) sd_event_source_set_description(a->pipe_event_source, "automount-io");
 637
 638         a->pipe_fd = p[0];
 639         a->dev_id = st.st_dev;
 640
 641         automount_set_state(a, AUTOMOUNT_WAITING);
 642
 643         return;
 644
 645 fail:
 646         log_unit_error_errno(UNIT(a), r, "Failed to initialize automounter: %m");
 647
 648         safe_close_pair(p);
 649
 650         if (mounted) {
 651                 r = repeat_unmount(a->where, MNT_DETACH);
 652                 if (r < 0)
 653                         log_error_errno(r, "Failed to unmount, ignoring: %m");
 654         }
 655
 656         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
 657 }
 658
 659 static void *expire_thread(void *p) {
 660         struct autofs_dev_ioctl param;
 661         _cleanup_(expire_data_freep) struct expire_data *data = (struct expire_data*)p;
 662         int r;
 663
 664         assert(data->dev_autofs_fd >= 0);
 665         assert(data->ioctl_fd >= 0);
 666
 667         init_autofs_dev_ioctl(&param);
 668         param.ioctlfd = data->ioctl_fd;
 669
 670         do {
 671                 r = ioctl(data->dev_autofs_fd, AUTOFS_DEV_IOCTL_EXPIRE, &param);
 672         } while (r >= 0);
 673
 674         if (errno != EAGAIN)
 675                 log_warning_errno(errno, "Failed to expire automount, ignoring: %m");
 676
 677         return NULL;
 678 }
 679
 680 static int automount_dispatch_expire(sd_event_source *source, usec_t usec, void *userdata) {
 681         Automount *a = AUTOMOUNT(userdata);
 682         _cleanup_(expire_data_freep) struct expire_data *data = NULL;
 683         int r;
 684
 685         assert(a);
 686         assert(source == a->expire_event_source);
 687
 688         data = new0(struct expire_data, 1);
 689         if (!data)
 690                 return log_oom();
 691
 692         data->ioctl_fd = -1;
 693
 694         data->dev_autofs_fd = fcntl(UNIT(a)->manager->dev_autofs_fd, F_DUPFD_CLOEXEC, 3);
 695         if (data->dev_autofs_fd < 0)
 696                 return log_unit_error_errno(UNIT(a), errno, "Failed to duplicate autofs fd: %m");
 697
 698         data->ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);
 699         if (data->ioctl_fd < 0)
 700                 return log_unit_error_errno(UNIT(a), data->ioctl_fd, "Couldn't open autofs ioctl fd: %m");
 701
 702         r = asynchronous_job(expire_thread, data);
 703         if (r < 0)
 704                 return log_unit_error_errno(UNIT(a), r, "Failed to start expire job: %m");
 705
 706         data = NULL;
 707
 708         return automount_start_expire(a);
 709 }
 710
 711 static int automount_start_expire(Automount *a) {
 712         usec_t timeout;
 713         int r;
 714
 715         assert(a);
 716
 717         if (a->timeout_idle_usec == 0)
 718                 return 0;
 719
 720         timeout = MAX(a->timeout_idle_usec/3, USEC_PER_SEC);
 721
 722         if (a->expire_event_source) {
 723                 r = sd_event_source_set_time_relative(a->expire_event_source, timeout);
 724                 if (r < 0)
 725                         return r;
 726
 727                 return sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_ONESHOT);
 728         }
 729
 730         r = sd_event_add_time_relative(
 731                         UNIT(a)->manager->event,
 732                         &a->expire_event_source,
 733                         CLOCK_MONOTONIC, timeout, 0,
 734                         automount_dispatch_expire, a);
 735         if (r < 0)
 736                 return r;
 737
 738         (void) sd_event_source_set_description(a->expire_event_source, "automount-expire");
 739
 740         return 0;
 741 }
 742
 743 static void automount_stop_expire(Automount *a) {
 744         assert(a);
 745
 746         if (!a->expire_event_source)
 747                 return;
 748
 749         (void) sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_OFF);
 750 }
 751
 752 static void automount_enter_running(Automount *a) {
 753         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 754         Unit *trigger;
 755         struct stat st;
 756         int r;
 757
 758         assert(a);
 759
 760         /* If the user masked our unit in the meantime, fail */
 761         if (UNIT(a)->load_state != UNIT_LOADED) {
 762                 log_unit_error(UNIT(a), "Suppressing automount event since unit is no longer loaded.");
 763                 goto fail;
 764         }
 765
 766         /* We don't take mount requests anymore if we are supposed to
 767          * shut down anyway */
 768         if (unit_stop_pending(UNIT(a))) {
 769                 log_unit_debug(UNIT(a), "Suppressing automount request since unit stop is scheduled.");
 770                 automount_send_ready(a, a->tokens, -EHOSTDOWN);
 771                 automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);
 772                 return;
 773         }
 774
 775         (void) mkdir_p_label(a->where, a->directory_mode);
 776
 777         /* Before we do anything, let's see if somebody is playing games with us? */
 778         if (lstat(a->where, &st) < 0) {
 779                 log_unit_warning_errno(UNIT(a), errno, "Failed to stat automount point: %m");
 780                 goto fail;
 781         }
 782
 783         /* The mount unit may have been explicitly started before we got the
 784          * autofs request. Ack it to unblock anything waiting on the mount point. */
 785         if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id) {
 786                 log_unit_info(UNIT(a), "Automount point already active?");
 787                 automount_send_ready(a, a->tokens, 0);
 788                 return;
 789         }
 790
 791         trigger = UNIT_TRIGGER(UNIT(a));
 792         if (!trigger) {
 793                 log_unit_error(UNIT(a), "Unit to trigger vanished.");
 794                 goto fail;
 795         }
 796
 797         r = manager_add_job(UNIT(a)->manager, JOB_START, trigger, JOB_REPLACE, NULL, &error, NULL);
 798         if (r < 0) {
 799                 log_unit_warning(UNIT(a), "Failed to queue mount startup job: %s", bus_error_message(&error, r));
 800                 goto fail;
 801         }
 802
 803         automount_set_state(a, AUTOMOUNT_RUNNING);
 804         return;
 805
 806 fail:
 807         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
 808 }
 809
 810 static int automount_start(Unit *u) {
 811         Automount *a = AUTOMOUNT(u);
 812         int r;
 813
 814         assert(a);
 815         assert(IN_SET(a->state, AUTOMOUNT_DEAD, AUTOMOUNT_FAILED));
 816
 817         if (path_is_mount_point(a->where, NULL, 0) > 0) {
 818                 log_unit_error(u, "Path %s is already a mount point, refusing start.", a->where);
 819                 return -EEXIST;
 820         }
 821
 822         r = unit_test_trigger_loaded(u);
 823         if (r < 0)
 824                 return r;
 825
 826         r = unit_test_start_limit(u);
 827         if (r < 0) {
 828                 automount_enter_dead(a, AUTOMOUNT_FAILURE_START_LIMIT_HIT);
 829                 return r;
 830         }
 831
 832         r = unit_acquire_invocation_id(u);
 833         if (r < 0)
 834                 return r;
 835
 836         a->result = AUTOMOUNT_SUCCESS;
 837         automount_enter_waiting(a);
 838         return 1;
 839 }
 840
 841 static int automount_stop(Unit *u) {
 842         Automount *a = AUTOMOUNT(u);
 843
 844         assert(a);
 845         assert(IN_SET(a->state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING));
 846
 847         automount_enter_dead(a, AUTOMOUNT_SUCCESS);
 848         return 1;
 849 }
 850
 851 static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {
 852         Automount *a = AUTOMOUNT(u);
 853         Iterator i;
 854         void *p;
 855         int r;
 856
 857         assert(a);
 858         assert(f);
 859         assert(fds);
 860
 861         (void) serialize_item(f, "state", automount_state_to_string(a->state));
 862         (void) serialize_item(f, "result", automount_result_to_string(a->result));
 863         (void) serialize_item_format(f, "dev-id", "%lu", (unsigned long) a->dev_id);
 864
 865         SET_FOREACH(p, a->tokens, i)
 866                 (void) serialize_item_format(f, "token", "%u", PTR_TO_UINT(p));
 867         SET_FOREACH(p, a->expire_tokens, i)
 868                 (void) serialize_item_format(f, "expire-token", "%u", PTR_TO_UINT(p));
 869
 870         r = serialize_fd(f, fds, "pipe-fd", a->pipe_fd);
 871         if (r < 0)
 872                 return r;
 873
 874         return 0;
 875 }
 876
 877 static int automount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 878         Automount *a = AUTOMOUNT(u);
 879         int r;
 880
 881         assert(a);
 882         assert(fds);
 883
 884         if (streq(key, "state")) {
 885                 AutomountState state;
 886
 887                 state = automount_state_from_string(value);
 888                 if (state < 0)
 889                         log_unit_debug(u, "Failed to parse state value: %s", value);
 890                 else
 891                         a->deserialized_state = state;
 892         } else if (streq(key, "result")) {
 893                 AutomountResult f;
 894
 895                 f = automount_result_from_string(value);
 896                 if (f < 0)
 897                         log_unit_debug(u, "Failed to parse result value: %s", value);
 898                 else if (f != AUTOMOUNT_SUCCESS)
 899                         a->result = f;
 900
 901         } else if (streq(key, "dev-id")) {
 902                 unsigned long d;
 903
 904                 if (safe_atolu(value, &d) < 0)
 905                         log_unit_debug(u, "Failed to parse dev-id value: %s", value);
 906                 else
 907                         a->dev_id = (dev_t) d;
 908
 909         } else if (streq(key, "token")) {
 910                 unsigned token;
 911
 912                 if (safe_atou(value, &token) < 0)
 913                         log_unit_debug(u, "Failed to parse token value: %s", value);
 914                 else {
 915                         r = set_ensure_put(&a->tokens, NULL, UINT_TO_PTR(token));
 916                         if (r < 0)
 917                                 log_unit_error_errno(u, r, "Failed to add token to set: %m");
 918                 }
 919         } else if (streq(key, "expire-token")) {
 920                 unsigned token;
 921
 922                 if (safe_atou(value, &token) < 0)
 923                         log_unit_debug(u, "Failed to parse token value: %s", value);
 924                 else {
 925                         r = set_ensure_put(&a->expire_tokens, NULL, UINT_TO_PTR(token));
 926                         if (r < 0)
 927                                 log_unit_error_errno(u, r, "Failed to add expire token to set: %m");
 928                 }
 929         } else if (streq(key, "pipe-fd")) {
 930                 int fd;
 931
 932                 if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
 933                         log_unit_debug(u, "Failed to parse pipe-fd value: %s", value);
 934                 else {
 935                         safe_close(a->pipe_fd);
 936                         a->pipe_fd = fdset_remove(fds, fd);
 937                 }
 938         } else
 939                 log_unit_debug(u, "Unknown serialization key: %s", key);
 940
 941         return 0;
 942 }
 943
 944 static UnitActiveState automount_active_state(Unit *u) {
 945         assert(u);
 946
 947         return state_translation_table[AUTOMOUNT(u)->state];
 948 }
 949
 950 static const char *automount_sub_state_to_string(Unit *u) {
 951         assert(u);
 952
 953         return automount_state_to_string(AUTOMOUNT(u)->state);
 954 }
 955
 956 static bool automount_may_gc(Unit *u) {
 957         Unit *t;
 958
 959         assert(u);
 960
 961         t = UNIT_TRIGGER(u);
 962         if (!t)
 963                 return true;
 964
 965         return UNIT_VTABLE(t)->may_gc(t);
 966 }
 967
 968 static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata) {
 969         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 970         union autofs_v5_packet_union packet;
 971         Automount *a = AUTOMOUNT(userdata);
 972         Unit *trigger;
 973         int r;
 974
 975         assert(a);
 976         assert(fd == a->pipe_fd);
 977
 978         if (events != EPOLLIN) {
 979                 log_unit_error(UNIT(a), "Got invalid poll event %"PRIu32" on pipe (fd=%d)", events, fd);
 980                 goto fail;
 981         }
 982
 983         r = loop_read_exact(a->pipe_fd, &packet, sizeof(packet), true);
 984         if (r < 0) {
 985                 log_unit_error_errno(UNIT(a), r, "Invalid read from pipe: %m");
 986                 goto fail;
 987         }
 988
 989         switch (packet.hdr.type) {
 990
 991         case autofs_ptype_missing_direct:
 992
 993                 if (packet.v5_packet.pid > 0) {
 994                         _cleanup_free_ char *p = NULL;
 995
 996                         get_process_comm(packet.v5_packet.pid, &p);
 997                         log_unit_info(UNIT(a), "Got automount request for %s, triggered by %"PRIu32" (%s)", a->where, packet.v5_packet.pid, strna(p));
 998                 } else
 999                         log_unit_debug(UNIT(a), "Got direct mount request on %s", a->where);
1000
1001                 r = set_ensure_put(&a->tokens, NULL, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
1002                 if (r < 0) {
1003                         log_unit_error_errno(UNIT(a), r, "Failed to remember token: %m");
1004                         goto fail;
1005                 }
1006
1007                 automount_enter_running(a);
1008                 break;
1009
1010         case autofs_ptype_expire_direct:
1011                 log_unit_debug(UNIT(a), "Got direct umount request on %s", a->where);
1012
1013                 automount_stop_expire(a);
1014
1015                 r = set_ensure_put(&a->expire_tokens, NULL, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
1016                 if (r < 0) {
1017                         log_unit_error_errno(UNIT(a), r, "Failed to remember token: %m");
1018                         goto fail;
1019                 }
1020
1021                 trigger = UNIT_TRIGGER(UNIT(a));
1022                 if (!trigger) {
1023                         log_unit_error(UNIT(a), "Unit to trigger vanished.");
1024                         goto fail;
1025                 }
1026
1027                 r = manager_add_job(UNIT(a)->manager, JOB_STOP, trigger, JOB_REPLACE, NULL, &error, NULL);
1028                 if (r < 0) {
1029                         log_unit_warning(UNIT(a), "Failed to queue umount startup job: %s", bus_error_message(&error, r));
1030                         goto fail;
1031                 }
1032                 break;
1033
1034         default:
1035                 log_unit_error(UNIT(a), "Received unknown automount request %i", packet.hdr.type);
1036                 break;
1037         }
1038
1039         return 0;
1040
1041 fail:
1042         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
1043         return 0;
1044 }
1045
1046 static void automount_shutdown(Manager *m) {
1047         assert(m);
1048
1049         m->dev_autofs_fd = safe_close(m->dev_autofs_fd);
1050 }
1051
1052 static void automount_reset_failed(Unit *u) {
1053         Automount *a = AUTOMOUNT(u);
1054
1055         assert(a);
1056
1057         if (a->state == AUTOMOUNT_FAILED)
1058                 automount_set_state(a, AUTOMOUNT_DEAD);
1059
1060         a->result = AUTOMOUNT_SUCCESS;
1061 }
1062
1063 static bool automount_supported(void) {
1064         static int supported = -1;
1065
1066         if (supported < 0)
1067                 supported = access("/dev/autofs", F_OK) >= 0;
1068
1069         return supported;
1070 }
1071
1072 static const char* const automount_result_table[_AUTOMOUNT_RESULT_MAX] = {
1073         [AUTOMOUNT_SUCCESS] = "success",
1074         [AUTOMOUNT_FAILURE_RESOURCES] = "resources",
1075         [AUTOMOUNT_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
1076         [AUTOMOUNT_FAILURE_MOUNT_START_LIMIT_HIT] = "mount-start-limit-hit",
1077 };
1078
1079 DEFINE_STRING_TABLE_LOOKUP(automount_result, AutomountResult);
1080
1081 const UnitVTable automount_vtable = {
1082         .object_size = sizeof(Automount),
1083
1084         .sections =
1085                 "Unit\0"
1086                 "Automount\0"
1087                 "Install\0",
1088         .private_section = "Automount",
1089
1090         .can_transient = true,
1091         .can_fail = true,
1092         .can_trigger = true,
1093
1094         .init = automount_init,
1095         .load = automount_load,
1096         .done = automount_done,
1097
1098         .coldplug = automount_coldplug,
1099
1100         .dump = automount_dump,
1101
1102         .start = automount_start,
1103         .stop = automount_stop,
1104
1105         .serialize = automount_serialize,
1106         .deserialize_item = automount_deserialize_item,
1107
1108         .active_state = automount_active_state,
1109         .sub_state_to_string = automount_sub_state_to_string,
1110
1111         .may_gc = automount_may_gc,
1112
1113         .trigger_notify = automount_trigger_notify,
1114
1115         .reset_failed = automount_reset_failed,
1116
1117         .bus_set_property = bus_automount_set_property,
1118
1119         .shutdown = automount_shutdown,
1120         .supported = automount_supported,
1121
1122         .status_message_formats = {
1123                 .finished_start_job = {
1124                         [JOB_DONE]       = "Set up automount %s.",
1125                         [JOB_FAILED]     = "Failed to set up automount %s.",
1126                 },
1127                 .finished_stop_job = {
1128                         [JOB_DONE]       = "Unset automount %s.",
1129                         [JOB_FAILED]     = "Failed to unset automount %s.",
1130                 },
1131         },
1132 };