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_AFTER, SPECIAL_LOCAL_FS_PRE_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
 156         if (r < 0)
 157                 return r;
 158
 159         r = unit_add_two_dependencies_by_name(UNIT(a), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
 160         if (r < 0)
 161                 return r;
 162
 163         return 0;
 164 }
 165
 166 static int automount_verify(Automount *a) {
 167         _cleanup_free_ char *e = NULL;
 168         int r;
 169
 170         assert(a);
 171         assert(UNIT(a)->load_state == UNIT_LOADED);
 172
 173         if (path_equal(a->where, "/")) {
 174                 log_unit_error(UNIT(a), "Cannot have an automount unit for the root directory. Refusing.");
 175                 return -ENOEXEC;
 176         }
 177
 178         r = unit_name_from_path(a->where, ".automount", &e);
 179         if (r < 0)
 180                 return log_unit_error_errno(UNIT(a), r, "Failed to generate unit name from path: %m");
 181
 182         if (!unit_has_name(UNIT(a), e)) {
 183                 log_unit_error(UNIT(a), "Where= setting doesn't match unit name. Refusing.");
 184                 return -ENOEXEC;
 185         }
 186
 187         return 0;
 188 }
 189
 190 static int automount_set_where(Automount *a) {
 191         int r;
 192
 193         assert(a);
 194
 195         if (a->where)
 196                 return 0;
 197
 198         r = unit_name_to_path(UNIT(a)->id, &a->where);
 199         if (r < 0)
 200                 return r;
 201
 202         path_simplify(a->where, false);
 203         return 1;
 204 }
 205
 206 static int automount_add_extras(Automount *a) {
 207         int r;
 208
 209         r = automount_set_where(a);
 210         if (r < 0)
 211                 return r;
 212
 213         r = automount_add_trigger_dependencies(a);
 214         if (r < 0)
 215                 return r;
 216
 217         r = automount_add_mount_dependencies(a);
 218         if (r < 0)
 219                 return r;
 220
 221         return automount_add_default_dependencies(a);
 222 }
 223
 224 static int automount_load(Unit *u) {
 225         Automount *a = AUTOMOUNT(u);
 226         int r;
 227
 228         assert(u);
 229         assert(u->load_state == UNIT_STUB);
 230
 231         /* Load a .automount file */
 232         r = unit_load_fragment_and_dropin(u, true);
 233         if (r < 0)
 234                 return r;
 235
 236         if (u->load_state != UNIT_LOADED)
 237                 return 0;
 238
 239         r = automount_add_extras(a);
 240         if (r < 0)
 241                 return r;
 242
 243         return automount_verify(a);
 244 }
 245
 246 static void automount_set_state(Automount *a, AutomountState state) {
 247         AutomountState old_state;
 248         assert(a);
 249
 250         if (a->state != state)
 251                 bus_unit_send_pending_change_signal(UNIT(a), false);
 252
 253         old_state = a->state;
 254         a->state = state;
 255
 256         if (state != AUTOMOUNT_RUNNING)
 257                 automount_stop_expire(a);
 258
 259         if (!IN_SET(state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING))
 260                 unmount_autofs(a);
 261
 262         if (state != old_state)
 263                 log_unit_debug(UNIT(a), "Changed %s -> %s", automount_state_to_string(old_state), automount_state_to_string(state));
 264
 265         unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state], 0);
 266 }
 267
 268 static int automount_coldplug(Unit *u) {
 269         Automount *a = AUTOMOUNT(u);
 270         int r;
 271
 272         assert(a);
 273         assert(a->state == AUTOMOUNT_DEAD);
 274
 275         if (a->deserialized_state == a->state)
 276                 return 0;
 277
 278         if (IN_SET(a->deserialized_state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING)) {
 279
 280                 r = automount_set_where(a);
 281                 if (r < 0)
 282                         return r;
 283
 284                 r = open_dev_autofs(u->manager);
 285                 if (r < 0)
 286                         return r;
 287
 288                 assert(a->pipe_fd >= 0);
 289
 290                 r = sd_event_add_io(u->manager->event, &a->pipe_event_source, a->pipe_fd, EPOLLIN, automount_dispatch_io, u);
 291                 if (r < 0)
 292                         return r;
 293
 294                 (void) sd_event_source_set_description(a->pipe_event_source, "automount-io");
 295                 if (a->deserialized_state == AUTOMOUNT_RUNNING) {
 296                         r = automount_start_expire(a);
 297                         if (r < 0)
 298                                 log_unit_warning_errno(UNIT(a), r, "Failed to start expiration timer, ignoring: %m");
 299                 }
 300
 301                 automount_set_state(a, a->deserialized_state);
 302         }
 303
 304         return 0;
 305 }
 306
 307 static void automount_dump(Unit *u, FILE *f, const char *prefix) {
 308         char time_string[FORMAT_TIMESPAN_MAX];
 309         Automount *a = AUTOMOUNT(u);
 310
 311         assert(a);
 312
 313         fprintf(f,
 314                 "%sAutomount State: %s\n"
 315                 "%sResult: %s\n"
 316                 "%sWhere: %s\n"
 317                 "%sDirectoryMode: %04o\n"
 318                 "%sTimeoutIdleUSec: %s\n",
 319                 prefix, automount_state_to_string(a->state),
 320                 prefix, automount_result_to_string(a->result),
 321                 prefix, a->where,
 322                 prefix, a->directory_mode,
 323                 prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, a->timeout_idle_usec, USEC_PER_SEC));
 324 }
 325
 326 static void automount_enter_dead(Automount *a, AutomountResult f) {
 327         assert(a);
 328
 329         if (a->result == AUTOMOUNT_SUCCESS)
 330                 a->result = f;
 331
 332         unit_log_result(UNIT(a), a->result == AUTOMOUNT_SUCCESS, automount_result_to_string(a->result));
 333         automount_set_state(a, a->result != AUTOMOUNT_SUCCESS ? AUTOMOUNT_FAILED : AUTOMOUNT_DEAD);
 334 }
 335
 336 static int open_dev_autofs(Manager *m) {
 337         struct autofs_dev_ioctl param;
 338
 339         assert(m);
 340
 341         if (m->dev_autofs_fd >= 0)
 342                 return m->dev_autofs_fd;
 343
 344         (void) label_fix("/dev/autofs", 0);
 345
 346         m->dev_autofs_fd = open("/dev/autofs", O_CLOEXEC|O_RDONLY);
 347         if (m->dev_autofs_fd < 0)
 348                 return log_error_errno(errno, "Failed to open /dev/autofs: %m");
 349
 350         init_autofs_dev_ioctl(&param);
 351         if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, &param) < 0) {
 352                 m->dev_autofs_fd = safe_close(m->dev_autofs_fd);
 353                 return -errno;
 354         }
 355
 356         log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
 357
 358         return m->dev_autofs_fd;
 359 }
 360
 361 static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
 362         struct autofs_dev_ioctl *param;
 363         size_t l;
 364
 365         assert(dev_autofs_fd >= 0);
 366         assert(where);
 367
 368         l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
 369         param = alloca(l);
 370
 371         init_autofs_dev_ioctl(param);
 372         param->size = l;
 373         param->ioctlfd = -1;
 374         param->openmount.devid = devid;
 375         strcpy(param->path, where);
 376
 377         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0)
 378                 return -errno;
 379
 380         if (param->ioctlfd < 0)
 381                 return -EIO;
 382
 383         (void) fd_cloexec(param->ioctlfd, true);
 384         return param->ioctlfd;
 385 }
 386
 387 static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
 388         uint32_t major, minor;
 389         struct autofs_dev_ioctl param;
 390
 391         assert(dev_autofs_fd >= 0);
 392         assert(ioctl_fd >= 0);
 393
 394         init_autofs_dev_ioctl(&param);
 395         param.ioctlfd = ioctl_fd;
 396
 397         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, &param) < 0)
 398                 return -errno;
 399
 400         major = param.protover.version;
 401
 402         init_autofs_dev_ioctl(&param);
 403         param.ioctlfd = ioctl_fd;
 404
 405         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, &param) < 0)
 406                 return -errno;
 407
 408         minor = param.protosubver.sub_version;
 409
 410         log_debug("Autofs protocol version %i.%i", major, minor);
 411         return 0;
 412 }
 413
 414 static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, usec_t usec) {
 415         struct autofs_dev_ioctl param;
 416
 417         assert(dev_autofs_fd >= 0);
 418         assert(ioctl_fd >= 0);
 419
 420         init_autofs_dev_ioctl(&param);
 421         param.ioctlfd = ioctl_fd;
 422
 423         if (usec == USEC_INFINITY)
 424                 param.timeout.timeout = 0;
 425         else
 426                 /* Convert to seconds, rounding up. */
 427                 param.timeout.timeout = DIV_ROUND_UP(usec, USEC_PER_SEC);
 428
 429         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)
 430                 return -errno;
 431
 432         return 0;
 433 }
 434
 435 static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
 436         struct autofs_dev_ioctl param;
 437
 438         assert(dev_autofs_fd >= 0);
 439         assert(ioctl_fd >= 0);
 440
 441         init_autofs_dev_ioctl(&param);
 442         param.ioctlfd = ioctl_fd;
 443
 444         if (status != 0) {
 445                 param.fail.token = token;
 446                 param.fail.status = status;
 447         } else
 448                 param.ready.token = token;
 449
 450         if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, &param) < 0)
 451                 return -errno;
 452
 453         return 0;
 454 }
 455
 456 static int automount_send_ready(Automount *a, Set *tokens, int status) {
 457         _cleanup_close_ int ioctl_fd = -1;
 458         unsigned token;
 459         int r;
 460
 461         assert(a);
 462         assert(status <= 0);
 463
 464         if (set_isempty(tokens))
 465                 return 0;
 466
 467         ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);
 468         if (ioctl_fd < 0)
 469                 return ioctl_fd;
 470
 471         if (status != 0)
 472                 log_unit_debug_errno(UNIT(a), status, "Sending failure: %m");
 473         else
 474                 log_unit_debug(UNIT(a), "Sending success.");
 475
 476         r = 0;
 477
 478         /* Autofs thankfully does not hand out 0 as a token */
 479         while ((token = PTR_TO_UINT(set_steal_first(tokens)))) {
 480                 int k;
 481
 482                 /* Autofs fun fact:
 483                  *
 484                  * if you pass a positive status code here, kernels
 485                  * prior to 4.12 will freeze! Yay! */
 486
 487                 k = autofs_send_ready(UNIT(a)->manager->dev_autofs_fd,
 488                                       ioctl_fd,
 489                                       token,
 490                                       status);
 491                 if (k < 0)
 492                         r = k;
 493         }
 494
 495         return r;
 496 }
 497
 498 static void automount_trigger_notify(Unit *u, Unit *other) {
 499         Automount *a = AUTOMOUNT(u);
 500         int r;
 501
 502         assert(a);
 503         assert(other);
 504
 505         /* Filter out invocations with bogus state */
 506         if (other->load_state != UNIT_LOADED || other->type != UNIT_MOUNT)
 507                 return;
 508
 509         /* Don't propagate state changes from the mount if we are already down */
 510         if (!IN_SET(a->state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING))
 511                 return;
 512
 513         /* Propagate start limit hit state */
 514         if (other->start_limit_hit) {
 515                 automount_enter_dead(a, AUTOMOUNT_FAILURE_MOUNT_START_LIMIT_HIT);
 516                 return;
 517         }
 518
 519         /* Don't propagate anything if there's still a job queued */
 520         if (other->job)
 521                 return;
 522
 523         /* The mount is successfully established */
 524         if (IN_SET(MOUNT(other)->state, MOUNT_MOUNTED, MOUNT_REMOUNTING)) {
 525                 (void) automount_send_ready(a, a->tokens, 0);
 526
 527                 r = automount_start_expire(a);
 528                 if (r < 0)
 529                         log_unit_warning_errno(UNIT(a), r, "Failed to start expiration timer, ignoring: %m");
 530
 531                 automount_set_state(a, AUTOMOUNT_RUNNING);
 532         }
 533
 534         if (IN_SET(MOUNT(other)->state,
 535                    MOUNT_MOUNTING, MOUNT_MOUNTING_DONE,
 536                    MOUNT_MOUNTED, MOUNT_REMOUNTING,
 537                    MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL,
 538                    MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL,
 539                    MOUNT_FAILED)) {
 540
 541                 (void) automount_send_ready(a, a->expire_tokens, -ENODEV);
 542         }
 543
 544         if (MOUNT(other)->state == MOUNT_DEAD)
 545                 (void) automount_send_ready(a, a->expire_tokens, 0);
 546
 547         /* The mount is in some unhappy state now, let's unfreeze any waiting clients */
 548         if (IN_SET(MOUNT(other)->state,
 549                    MOUNT_DEAD, MOUNT_UNMOUNTING,
 550                    MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL,
 551                    MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL,
 552                    MOUNT_FAILED)) {
 553
 554                 (void) automount_send_ready(a, a->tokens, -ENODEV);
 555
 556                 automount_set_state(a, AUTOMOUNT_WAITING);
 557         }
 558 }
 559
 560 static void automount_enter_waiting(Automount *a) {
 561         _cleanup_close_ int ioctl_fd = -1;
 562         int p[2] = { -1, -1 };
 563         char name[STRLEN("systemd-") + DECIMAL_STR_MAX(pid_t) + 1];
 564         char options[STRLEN("fd=,pgrp=,minproto=5,maxproto=5,direct")
 565                      + DECIMAL_STR_MAX(int) + DECIMAL_STR_MAX(gid_t) + 1];
 566         bool mounted = false;
 567         int r, dev_autofs_fd;
 568         struct stat st;
 569
 570         assert(a);
 571         assert(a->pipe_fd < 0);
 572         assert(a->where);
 573
 574         set_clear(a->tokens);
 575
 576         r = unit_fail_if_noncanonical(UNIT(a), a->where);
 577         if (r < 0)
 578                 goto fail;
 579
 580         (void) mkdir_p_label(a->where, a->directory_mode);
 581
 582         unit_warn_if_dir_nonempty(UNIT(a), a->where);
 583
 584         dev_autofs_fd = open_dev_autofs(UNIT(a)->manager);
 585         if (dev_autofs_fd < 0) {
 586                 r = dev_autofs_fd;
 587                 goto fail;
 588         }
 589
 590         if (pipe2(p, O_CLOEXEC) < 0) {
 591                 r = -errno;
 592                 goto fail;
 593         }
 594         r = fd_nonblock(p[0], true);
 595         if (r < 0)
 596                 goto fail;
 597
 598         xsprintf(options, "fd=%i,pgrp="PID_FMT",minproto=5,maxproto=5,direct", p[1], getpgrp());
 599         xsprintf(name, "systemd-"PID_FMT, getpid_cached());
 600         if (mount(name, a->where, "autofs", 0, options) < 0) {
 601                 r = -errno;
 602                 goto fail;
 603         }
 604
 605         mounted = true;
 606
 607         p[1] = safe_close(p[1]);
 608
 609         if (stat(a->where, &st) < 0) {
 610                 r = -errno;
 611                 goto fail;
 612         }
 613
 614         ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev);
 615         if (ioctl_fd < 0) {
 616                 r = ioctl_fd;
 617                 goto fail;
 618         }
 619
 620         r = autofs_protocol(dev_autofs_fd, ioctl_fd);
 621         if (r < 0)
 622                 goto fail;
 623
 624         r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, a->timeout_idle_usec);
 625         if (r < 0)
 626                 goto fail;
 627
 628         r = sd_event_add_io(UNIT(a)->manager->event, &a->pipe_event_source, p[0], EPOLLIN, automount_dispatch_io, a);
 629         if (r < 0)
 630                 goto fail;
 631
 632         (void) sd_event_source_set_description(a->pipe_event_source, "automount-io");
 633
 634         a->pipe_fd = p[0];
 635         a->dev_id = st.st_dev;
 636
 637         automount_set_state(a, AUTOMOUNT_WAITING);
 638
 639         return;
 640
 641 fail:
 642         log_unit_error_errno(UNIT(a), r, "Failed to initialize automounter: %m");
 643
 644         safe_close_pair(p);
 645
 646         if (mounted) {
 647                 r = repeat_unmount(a->where, MNT_DETACH);
 648                 if (r < 0)
 649                         log_error_errno(r, "Failed to unmount, ignoring: %m");
 650         }
 651
 652         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
 653 }
 654
 655 static void *expire_thread(void *p) {
 656         struct autofs_dev_ioctl param;
 657         _cleanup_(expire_data_freep) struct expire_data *data = (struct expire_data*)p;
 658         int r;
 659
 660         assert(data->dev_autofs_fd >= 0);
 661         assert(data->ioctl_fd >= 0);
 662
 663         init_autofs_dev_ioctl(&param);
 664         param.ioctlfd = data->ioctl_fd;
 665
 666         do {
 667                 r = ioctl(data->dev_autofs_fd, AUTOFS_DEV_IOCTL_EXPIRE, &param);
 668         } while (r >= 0);
 669
 670         if (errno != EAGAIN)
 671                 log_warning_errno(errno, "Failed to expire automount, ignoring: %m");
 672
 673         return NULL;
 674 }
 675
 676 static int automount_dispatch_expire(sd_event_source *source, usec_t usec, void *userdata) {
 677         Automount *a = AUTOMOUNT(userdata);
 678         _cleanup_(expire_data_freep) struct expire_data *data = NULL;
 679         int r;
 680
 681         assert(a);
 682         assert(source == a->expire_event_source);
 683
 684         data = new0(struct expire_data, 1);
 685         if (!data)
 686                 return log_oom();
 687
 688         data->ioctl_fd = -1;
 689
 690         data->dev_autofs_fd = fcntl(UNIT(a)->manager->dev_autofs_fd, F_DUPFD_CLOEXEC, 3);
 691         if (data->dev_autofs_fd < 0)
 692                 return log_unit_error_errno(UNIT(a), errno, "Failed to duplicate autofs fd: %m");
 693
 694         data->ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);
 695         if (data->ioctl_fd < 0)
 696                 return log_unit_error_errno(UNIT(a), data->ioctl_fd, "Couldn't open autofs ioctl fd: %m");
 697
 698         r = asynchronous_job(expire_thread, data);
 699         if (r < 0)
 700                 return log_unit_error_errno(UNIT(a), r, "Failed to start expire job: %m");
 701
 702         data = NULL;
 703
 704         return automount_start_expire(a);
 705 }
 706
 707 static int automount_start_expire(Automount *a) {
 708         int r;
 709         usec_t timeout;
 710
 711         assert(a);
 712
 713         if (a->timeout_idle_usec == 0)
 714                 return 0;
 715
 716         timeout = now(CLOCK_MONOTONIC) + MAX(a->timeout_idle_usec/3, USEC_PER_SEC);
 717
 718         if (a->expire_event_source) {
 719                 r = sd_event_source_set_time(a->expire_event_source, timeout);
 720                 if (r < 0)
 721                         return r;
 722
 723                 return sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_ONESHOT);
 724         }
 725
 726         r = sd_event_add_time(
 727                         UNIT(a)->manager->event,
 728                         &a->expire_event_source,
 729                         CLOCK_MONOTONIC, timeout, 0,
 730                         automount_dispatch_expire, a);
 731         if (r < 0)
 732                 return r;
 733
 734         (void) sd_event_source_set_description(a->expire_event_source, "automount-expire");
 735
 736         return 0;
 737 }
 738
 739 static void automount_stop_expire(Automount *a) {
 740         assert(a);
 741
 742         if (!a->expire_event_source)
 743                 return;
 744
 745         (void) sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_OFF);
 746 }
 747
 748 static void automount_enter_running(Automount *a) {
 749         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 750         Unit *trigger;
 751         struct stat st;
 752         int r;
 753
 754         assert(a);
 755
 756         /* If the user masked our unit in the meantime, fail */
 757         if (UNIT(a)->load_state != UNIT_LOADED) {
 758                 log_unit_error(UNIT(a), "Suppressing automount event since unit is no longer loaded.");
 759                 goto fail;
 760         }
 761
 762         /* We don't take mount requests anymore if we are supposed to
 763          * shut down anyway */
 764         if (unit_stop_pending(UNIT(a))) {
 765                 log_unit_debug(UNIT(a), "Suppressing automount request since unit stop is scheduled.");
 766                 automount_send_ready(a, a->tokens, -EHOSTDOWN);
 767                 automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);
 768                 return;
 769         }
 770
 771         (void) mkdir_p_label(a->where, a->directory_mode);
 772
 773         /* Before we do anything, let's see if somebody is playing games with us? */
 774         if (lstat(a->where, &st) < 0) {
 775                 log_unit_warning_errno(UNIT(a), errno, "Failed to stat automount point: %m");
 776                 goto fail;
 777         }
 778
 779         /* The mount unit may have been explicitly started before we got the
 780          * autofs request. Ack it to unblock anything waiting on the mount point. */
 781         if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id) {
 782                 log_unit_info(UNIT(a), "Automount point already active?");
 783                 automount_send_ready(a, a->tokens, 0);
 784                 return;
 785         }
 786
 787         trigger = UNIT_TRIGGER(UNIT(a));
 788         if (!trigger) {
 789                 log_unit_error(UNIT(a), "Unit to trigger vanished.");
 790                 goto fail;
 791         }
 792
 793         r = manager_add_job(UNIT(a)->manager, JOB_START, trigger, JOB_REPLACE, NULL, &error, NULL);
 794         if (r < 0) {
 795                 log_unit_warning(UNIT(a), "Failed to queue mount startup job: %s", bus_error_message(&error, r));
 796                 goto fail;
 797         }
 798
 799         automount_set_state(a, AUTOMOUNT_RUNNING);
 800         return;
 801
 802 fail:
 803         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
 804 }
 805
 806 static int automount_start(Unit *u) {
 807         Automount *a = AUTOMOUNT(u);
 808         int r;
 809
 810         assert(a);
 811         assert(IN_SET(a->state, AUTOMOUNT_DEAD, AUTOMOUNT_FAILED));
 812
 813         if (path_is_mount_point(a->where, NULL, 0) > 0) {
 814                 log_unit_error(u, "Path %s is already a mount point, refusing start.", a->where);
 815                 return -EEXIST;
 816         }
 817
 818         r = unit_test_trigger_loaded(u);
 819         if (r < 0)
 820                 return r;
 821
 822         r = unit_test_start_limit(u);
 823         if (r < 0) {
 824                 automount_enter_dead(a, AUTOMOUNT_FAILURE_START_LIMIT_HIT);
 825                 return r;
 826         }
 827
 828         r = unit_acquire_invocation_id(u);
 829         if (r < 0)
 830                 return r;
 831
 832         a->result = AUTOMOUNT_SUCCESS;
 833         automount_enter_waiting(a);
 834         return 1;
 835 }
 836
 837 static int automount_stop(Unit *u) {
 838         Automount *a = AUTOMOUNT(u);
 839
 840         assert(a);
 841         assert(IN_SET(a->state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING));
 842
 843         automount_enter_dead(a, AUTOMOUNT_SUCCESS);
 844         return 1;
 845 }
 846
 847 static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {
 848         Automount *a = AUTOMOUNT(u);
 849         Iterator i;
 850         void *p;
 851         int r;
 852
 853         assert(a);
 854         assert(f);
 855         assert(fds);
 856
 857         (void) serialize_item(f, "state", automount_state_to_string(a->state));
 858         (void) serialize_item(f, "result", automount_result_to_string(a->result));
 859         (void) serialize_item_format(f, "dev-id", "%lu", (unsigned long) a->dev_id);
 860
 861         SET_FOREACH(p, a->tokens, i)
 862                 (void) serialize_item_format(f, "token", "%u", PTR_TO_UINT(p));
 863         SET_FOREACH(p, a->expire_tokens, i)
 864                 (void) serialize_item_format(f, "expire-token", "%u", PTR_TO_UINT(p));
 865
 866         r = serialize_fd(f, fds, "pipe-fd", a->pipe_fd);
 867         if (r < 0)
 868                 return r;
 869
 870         return 0;
 871 }
 872
 873 static int automount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 874         Automount *a = AUTOMOUNT(u);
 875         int r;
 876
 877         assert(a);
 878         assert(fds);
 879
 880         if (streq(key, "state")) {
 881                 AutomountState state;
 882
 883                 state = automount_state_from_string(value);
 884                 if (state < 0)
 885                         log_unit_debug(u, "Failed to parse state value: %s", value);
 886                 else
 887                         a->deserialized_state = state;
 888         } else if (streq(key, "result")) {
 889                 AutomountResult f;
 890
 891                 f = automount_result_from_string(value);
 892                 if (f < 0)
 893                         log_unit_debug(u, "Failed to parse result value: %s", value);
 894                 else if (f != AUTOMOUNT_SUCCESS)
 895                         a->result = f;
 896
 897         } else if (streq(key, "dev-id")) {
 898                 unsigned long d;
 899
 900                 if (safe_atolu(value, &d) < 0)
 901                         log_unit_debug(u, "Failed to parse dev-id value: %s", value);
 902                 else
 903                         a->dev_id = (dev_t) d;
 904
 905         } else if (streq(key, "token")) {
 906                 unsigned token;
 907
 908                 if (safe_atou(value, &token) < 0)
 909                         log_unit_debug(u, "Failed to parse token value: %s", value);
 910                 else {
 911                         r = set_ensure_allocated(&a->tokens, NULL);
 912                         if (r < 0) {
 913                                 log_oom();
 914                                 return 0;
 915                         }
 916
 917                         r = set_put(a->tokens, UINT_TO_PTR(token));
 918                         if (r < 0)
 919                                 log_unit_error_errno(u, r, "Failed to add token to set: %m");
 920                 }
 921         } else if (streq(key, "expire-token")) {
 922                 unsigned token;
 923
 924                 if (safe_atou(value, &token) < 0)
 925                         log_unit_debug(u, "Failed to parse token value: %s", value);
 926                 else {
 927                         r = set_ensure_allocated(&a->expire_tokens, NULL);
 928                         if (r < 0) {
 929                                 log_oom();
 930                                 return 0;
 931                         }
 932
 933                         r = set_put(a->expire_tokens, UINT_TO_PTR(token));
 934                         if (r < 0)
 935                                 log_unit_error_errno(u, r, "Failed to add expire token to set: %m");
 936                 }
 937         } else if (streq(key, "pipe-fd")) {
 938                 int fd;
 939
 940                 if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
 941                         log_unit_debug(u, "Failed to parse pipe-fd value: %s", value);
 942                 else {
 943                         safe_close(a->pipe_fd);
 944                         a->pipe_fd = fdset_remove(fds, fd);
 945                 }
 946         } else
 947                 log_unit_debug(u, "Unknown serialization key: %s", key);
 948
 949         return 0;
 950 }
 951
 952 static UnitActiveState automount_active_state(Unit *u) {
 953         assert(u);
 954
 955         return state_translation_table[AUTOMOUNT(u)->state];
 956 }
 957
 958 static const char *automount_sub_state_to_string(Unit *u) {
 959         assert(u);
 960
 961         return automount_state_to_string(AUTOMOUNT(u)->state);
 962 }
 963
 964 static bool automount_may_gc(Unit *u) {
 965         Unit *t;
 966
 967         assert(u);
 968
 969         t = UNIT_TRIGGER(u);
 970         if (!t)
 971                 return true;
 972
 973         return UNIT_VTABLE(t)->may_gc(t);
 974 }
 975
 976 static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata) {
 977         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 978         union autofs_v5_packet_union packet;
 979         Automount *a = AUTOMOUNT(userdata);
 980         Unit *trigger;
 981         int r;
 982
 983         assert(a);
 984         assert(fd == a->pipe_fd);
 985
 986         if (events != EPOLLIN) {
 987                 log_unit_error(UNIT(a), "Got invalid poll event %"PRIu32" on pipe (fd=%d)", events, fd);
 988                 goto fail;
 989         }
 990
 991         r = loop_read_exact(a->pipe_fd, &packet, sizeof(packet), true);
 992         if (r < 0) {
 993                 log_unit_error_errno(UNIT(a), r, "Invalid read from pipe: %m");
 994                 goto fail;
 995         }
 996
 997         switch (packet.hdr.type) {
 998
 999         case autofs_ptype_missing_direct:
1000
1001                 if (packet.v5_packet.pid > 0) {
1002                         _cleanup_free_ char *p = NULL;
1003
1004                         get_process_comm(packet.v5_packet.pid, &p);
1005                         log_unit_info(UNIT(a), "Got automount request for %s, triggered by %"PRIu32" (%s)", a->where, packet.v5_packet.pid, strna(p));
1006                 } else
1007                         log_unit_debug(UNIT(a), "Got direct mount request on %s", a->where);
1008
1009                 r = set_ensure_allocated(&a->tokens, NULL);
1010                 if (r < 0) {
1011                         log_unit_error(UNIT(a), "Failed to allocate token set.");
1012                         goto fail;
1013                 }
1014
1015                 r = set_put(a->tokens, 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                 automount_enter_running(a);
1022                 break;
1023
1024         case autofs_ptype_expire_direct:
1025                 log_unit_debug(UNIT(a), "Got direct umount request on %s", a->where);
1026
1027                 automount_stop_expire(a);
1028
1029                 r = set_ensure_allocated(&a->expire_tokens, NULL);
1030                 if (r < 0) {
1031                         log_unit_error(UNIT(a), "Failed to allocate token set.");
1032                         goto fail;
1033                 }
1034
1035                 r = set_put(a->expire_tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
1036                 if (r < 0) {
1037                         log_unit_error_errno(UNIT(a), r, "Failed to remember token: %m");
1038                         goto fail;
1039                 }
1040
1041                 trigger = UNIT_TRIGGER(UNIT(a));
1042                 if (!trigger) {
1043                         log_unit_error(UNIT(a), "Unit to trigger vanished.");
1044                         goto fail;
1045                 }
1046
1047                 r = manager_add_job(UNIT(a)->manager, JOB_STOP, trigger, JOB_REPLACE, NULL, &error, NULL);
1048                 if (r < 0) {
1049                         log_unit_warning(UNIT(a), "Failed to queue umount startup job: %s", bus_error_message(&error, r));
1050                         goto fail;
1051                 }
1052                 break;
1053
1054         default:
1055                 log_unit_error(UNIT(a), "Received unknown automount request %i", packet.hdr.type);
1056                 break;
1057         }
1058
1059         return 0;
1060
1061 fail:
1062         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
1063         return 0;
1064 }
1065
1066 static void automount_shutdown(Manager *m) {
1067         assert(m);
1068
1069         m->dev_autofs_fd = safe_close(m->dev_autofs_fd);
1070 }
1071
1072 static void automount_reset_failed(Unit *u) {
1073         Automount *a = AUTOMOUNT(u);
1074
1075         assert(a);
1076
1077         if (a->state == AUTOMOUNT_FAILED)
1078                 automount_set_state(a, AUTOMOUNT_DEAD);
1079
1080         a->result = AUTOMOUNT_SUCCESS;
1081 }
1082
1083 static bool automount_supported(void) {
1084         static int supported = -1;
1085
1086         if (supported < 0)
1087                 supported = access("/dev/autofs", F_OK) >= 0;
1088
1089         return supported;
1090 }
1091
1092 static const char* const automount_result_table[_AUTOMOUNT_RESULT_MAX] = {
1093         [AUTOMOUNT_SUCCESS] = "success",
1094         [AUTOMOUNT_FAILURE_RESOURCES] = "resources",
1095         [AUTOMOUNT_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
1096         [AUTOMOUNT_FAILURE_MOUNT_START_LIMIT_HIT] = "mount-start-limit-hit",
1097 };
1098
1099 DEFINE_STRING_TABLE_LOOKUP(automount_result, AutomountResult);
1100
1101 const UnitVTable automount_vtable = {
1102         .object_size = sizeof(Automount),
1103
1104         .sections =
1105                 "Unit\0"
1106                 "Automount\0"
1107                 "Install\0",
1108
1109         .can_transient = true,
1110         .can_fail = true,
1111         .can_trigger = true,
1112
1113         .init = automount_init,
1114         .load = automount_load,
1115         .done = automount_done,
1116
1117         .coldplug = automount_coldplug,
1118
1119         .dump = automount_dump,
1120
1121         .start = automount_start,
1122         .stop = automount_stop,
1123
1124         .serialize = automount_serialize,
1125         .deserialize_item = automount_deserialize_item,
1126
1127         .active_state = automount_active_state,
1128         .sub_state_to_string = automount_sub_state_to_string,
1129
1130         .may_gc = automount_may_gc,
1131
1132         .trigger_notify = automount_trigger_notify,
1133
1134         .reset_failed = automount_reset_failed,
1135
1136         .bus_vtable = bus_automount_vtable,
1137         .bus_set_property = bus_automount_set_property,
1138
1139         .shutdown = automount_shutdown,
1140         .supported = automount_supported,
1141
1142         .status_message_formats = {
1143                 .finished_start_job = {
1144                         [JOB_DONE]       = "Set up automount %s.",
1145                         [JOB_FAILED]     = "Failed to set up automount %s.",
1146                 },
1147                 .finished_stop_job = {
1148                         [JOB_DONE]       = "Unset automount %s.",
1149                         [JOB_FAILED]     = "Failed to unset automount %s.",
1150                 },
1151         },
1152 };