git.ozlabs.org Git - petitboot/blob - discover/device-handler.c

   1 #include <assert.h>
   2 #include <stdlib.h>
   3 #include <stdbool.h>
   4 #include <unistd.h>
   5 #include <string.h>
   6 #include <errno.h>
   7 #include <mntent.h>
   8 #include <locale.h>
   9 #include <sys/stat.h>
  10 #include <sys/wait.h>
  11 #include <sys/mount.h>
  12
  13 #include <talloc/talloc.h>
  14 #include <list/list.h>
  15 #include <log/log.h>
  16 #include <types/types.h>
  17 #include <system/system.h>
  18 #include <process/process.h>
  19 #include <url/url.h>
  20 #include <i18n/i18n.h>
  21
  22 #include <sys/sysmacros.h>
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <netdb.h>
  26 #include <arpa/inet.h>
  27
  28 #include "device-handler.h"
  29 #include "discover-server.h"
  30 #include "devmapper.h"
  31 #include "user-event.h"
  32 #include "platform.h"
  33 #include "event.h"
  34 #include "parser.h"
  35 #include "resource.h"
  36 #include "paths.h"
  37 #include "sysinfo.h"
  38 #include "boot.h"
  39 #include "udev.h"
  40 #include "network.h"
  41 #include "ipmi.h"
  42
  43 enum default_priority {
  44         DEFAULT_PRIORITY_REMOTE         = 1,
  45         DEFAULT_PRIORITY_LOCAL_FIRST    = 2,
  46         DEFAULT_PRIORITY_LOCAL_LAST     = 0xfe,
  47         DEFAULT_PRIORITY_DISABLED       = 0xff,
  48 };
  49
  50 struct progress_info {
  51         unsigned int                    percentage;
  52         unsigned long                   size;           /* size in bytes */
  53
  54         const struct process_info       *procinfo;
  55         struct list_item        list;
  56 };
  57
  58 struct device_handler {
  59         struct discover_server  *server;
  60         int                     dry_run;
  61
  62         struct pb_udev          *udev;
  63         struct network          *network;
  64         struct user_event       *user_event;
  65
  66         struct discover_device  **devices;
  67         unsigned int            n_devices;
  68
  69         struct ramdisk_device   **ramdisks;
  70         unsigned int            n_ramdisks;
  71
  72         struct waitset          *waitset;
  73         struct waiter           *timeout_waiter;
  74         bool                    autoboot_enabled;
  75         unsigned int            sec_to_boot;
  76
  77         struct discover_boot_option *default_boot_option;
  78         int                     default_boot_option_priority;
  79
  80         struct list             unresolved_boot_options;
  81
  82         struct boot_task        *pending_boot;
  83         bool                    pending_boot_is_default;
  84
  85         struct list             progress;
  86         unsigned int            n_progress;
  87 };
  88
  89 static int mount_device(struct discover_device *dev);
  90 static int umount_device(struct discover_device *dev);
  91
  92 static int device_handler_init_sources(struct device_handler *handler);
  93 static void device_handler_reinit_sources(struct device_handler *handler);
  94
  95 static void device_handler_update_lang(const char *lang);
  96
  97 void discover_context_add_boot_option(struct discover_context *ctx,
  98                 struct discover_boot_option *boot_option)
  99 {
 100         boot_option->source = ctx->parser;
 101         list_add_tail(&ctx->boot_options, &boot_option->list);
 102         talloc_steal(ctx, boot_option);
 103 }
 104
 105 /**
 106  * device_handler_get_device_count - Get the count of current handler devices.
 107  */
 108
 109 int device_handler_get_device_count(const struct device_handler *handler)
 110 {
 111         return handler->n_devices;
 112 }
 113
 114 /**
 115  * device_handler_get_device - Get a handler device by index.
 116  */
 117
 118 const struct discover_device *device_handler_get_device(
 119         const struct device_handler *handler, unsigned int index)
 120 {
 121         if (index >= handler->n_devices) {
 122                 assert(0 && "bad index");
 123                 return NULL;
 124         }
 125
 126         return handler->devices[index];
 127 }
 128
 129 struct network *device_handler_get_network(
 130                 const struct device_handler *handler)
 131 {
 132         return handler->network;
 133 }
 134
 135 struct discover_boot_option *discover_boot_option_create(
 136                 struct discover_context *ctx,
 137                 struct discover_device *device)
 138 {
 139         struct discover_boot_option *opt;
 140
 141         opt = talloc_zero(ctx, struct discover_boot_option);
 142         opt->option = talloc_zero(opt, struct boot_option);
 143         opt->device = device;
 144
 145         return opt;
 146 }
 147
 148 static int device_match_uuid(struct discover_device *dev, const char *uuid)
 149 {
 150         return dev->uuid && !strcmp(dev->uuid, uuid);
 151 }
 152
 153 static int device_match_label(struct discover_device *dev, const char *label)
 154 {
 155         return dev->label && !strcmp(dev->label, label);
 156 }
 157
 158 static int device_match_id(struct discover_device *dev, const char *id)
 159 {
 160         return !strcmp(dev->device->id, id);
 161 }
 162
 163 static int device_match_serial(struct discover_device *dev, const char *serial)
 164 {
 165         const char *val = discover_device_get_param(dev, "ID_SERIAL");
 166         return val && !strcmp(val, serial);
 167 }
 168
 169 static struct discover_device *device_lookup(
 170                 struct device_handler *device_handler,
 171                 int (match_fn)(struct discover_device *, const char *),
 172                 const char *str)
 173 {
 174         struct discover_device *dev;
 175         unsigned int i;
 176
 177         if (!str)
 178                 return NULL;
 179
 180         for (i = 0; i < device_handler->n_devices; i++) {
 181                 dev = device_handler->devices[i];
 182
 183                 if (match_fn(dev, str))
 184                         return dev;
 185         }
 186
 187         return NULL;
 188 }
 189
 190 struct discover_device *device_lookup_by_name(struct device_handler *handler,
 191                 const char *name)
 192 {
 193         if (!strncmp(name, "/dev/", strlen("/dev/")))
 194                 name += strlen("/dev/");
 195
 196         return device_lookup_by_id(handler, name);
 197 }
 198
 199 struct discover_device *device_lookup_by_uuid(
 200                 struct device_handler *device_handler,
 201                 const char *uuid)
 202 {
 203         return device_lookup(device_handler, device_match_uuid, uuid);
 204 }
 205
 206 struct discover_device *device_lookup_by_label(
 207                 struct device_handler *device_handler,
 208                 const char *label)
 209 {
 210         return device_lookup(device_handler, device_match_label, label);
 211 }
 212
 213 struct discover_device *device_lookup_by_id(
 214                 struct device_handler *device_handler,
 215                 const char *id)
 216 {
 217         return device_lookup(device_handler, device_match_id, id);
 218 }
 219
 220 struct discover_device *device_lookup_by_serial(
 221                 struct device_handler *device_handler,
 222                 const char *serial)
 223 {
 224         return device_lookup(device_handler, device_match_serial, serial);
 225 }
 226
 227 void device_handler_destroy(struct device_handler *handler)
 228 {
 229         talloc_free(handler);
 230 }
 231
 232 static int destroy_device(void *arg)
 233 {
 234         struct discover_device *dev = arg;
 235
 236         umount_device(dev);
 237
 238         return 0;
 239 }
 240
 241 struct discover_device *discover_device_create(struct device_handler *handler,
 242                 const char *uuid, const char *id)
 243 {
 244         struct discover_device *dev;
 245
 246         if (uuid)
 247                 dev = device_lookup_by_uuid(handler, uuid);
 248         else
 249                 dev = device_lookup_by_id(handler, id);
 250
 251         if (dev)
 252                 return dev;
 253
 254         dev = talloc_zero(handler, struct discover_device);
 255         dev->device = talloc_zero(dev, struct device);
 256         dev->device->id = talloc_strdup(dev->device, id);
 257         dev->uuid = talloc_strdup(dev, uuid);
 258         list_init(&dev->params);
 259         list_init(&dev->boot_options);
 260
 261         talloc_set_destructor(dev, destroy_device);
 262
 263         return dev;
 264 }
 265
 266 struct discover_device_param {
 267         char                    *name;
 268         char                    *value;
 269         struct list_item        list;
 270 };
 271
 272 void discover_device_set_param(struct discover_device *device,
 273                 const char *name, const char *value)
 274 {
 275         struct discover_device_param *param;
 276         bool found = false;
 277
 278         list_for_each_entry(&device->params, param, list) {
 279                 if (!strcmp(param->name, name)) {
 280                         found = true;
 281                         break;
 282                 }
 283         }
 284
 285         if (!found) {
 286                 if (!value)
 287                         return;
 288                 param = talloc(device, struct discover_device_param);
 289                 param->name = talloc_strdup(param, name);
 290                 list_add(&device->params, &param->list);
 291         } else {
 292                 if (!value) {
 293                         list_remove(&param->list);
 294                         talloc_free(param);
 295                         return;
 296                 }
 297                 talloc_free(param->value);
 298         }
 299
 300         param->value = talloc_strdup(param, value);
 301 }
 302
 303 const char *discover_device_get_param(struct discover_device *device,
 304                 const char *name)
 305 {
 306         struct discover_device_param *param;
 307
 308         list_for_each_entry(&device->params, param, list) {
 309                 if (!strcmp(param->name, name))
 310                         return param->value;
 311         }
 312         return NULL;
 313 }
 314
 315 static void set_env_variables(const struct config *config)
 316 {
 317         if (config->http_proxy)
 318                 setenv("http_proxy", config->http_proxy, 1);
 319         else
 320                 unsetenv("http_proxy");
 321
 322         if (config->https_proxy)
 323                 setenv("https_proxy", config->https_proxy, 1);
 324         else
 325                 unsetenv("https_proxy");
 326
 327         /* Reduce noise in the log from LVM listing open file descriptors */
 328         setenv("LVM_SUPPRESS_FD_WARNINGS", "1", 1);
 329 }
 330
 331 struct device_handler *device_handler_init(struct discover_server *server,
 332                 struct waitset *waitset, int dry_run)
 333 {
 334         struct device_handler *handler;
 335         int rc;
 336
 337         handler = talloc_zero(NULL, struct device_handler);
 338         handler->server = server;
 339         handler->waitset = waitset;
 340         handler->dry_run = dry_run;
 341         handler->autoboot_enabled = config_autoboot_active(config_get());
 342
 343         list_init(&handler->unresolved_boot_options);
 344
 345         list_init(&handler->progress);
 346
 347         /* set up our mount point base */
 348         pb_mkdir_recursive(mount_base());
 349
 350         parser_init();
 351
 352         if (config_get()->safe_mode)
 353                 return handler;
 354
 355         set_env_variables(config_get());
 356
 357         rc = device_handler_init_sources(handler);
 358         if (rc) {
 359                 talloc_free(handler);
 360                 return NULL;
 361         }
 362
 363         return handler;
 364 }
 365
 366 void device_handler_reinit(struct device_handler *handler)
 367 {
 368         struct discover_boot_option *opt, *tmp;
 369         struct ramdisk_device *ramdisk;
 370         unsigned int i;
 371
 372         device_handler_cancel_default(handler);
 373         /* Cancel any pending non-default boot */
 374         if (handler->pending_boot) {
 375                 boot_cancel(handler->pending_boot);
 376                 handler->pending_boot = NULL;
 377                 handler->pending_boot_is_default = false;
 378         }
 379
 380         /* Cancel any remaining async jobs */
 381         process_stop_async_all();
 382         pending_network_jobs_cancel();
 383
 384         /* free unresolved boot options */
 385         list_for_each_entry_safe(&handler->unresolved_boot_options,
 386                         opt, tmp, list)
 387                 talloc_free(opt);
 388         list_init(&handler->unresolved_boot_options);
 389
 390         /* drop all devices */
 391         for (i = 0; i < handler->n_devices; i++) {
 392                 discover_server_notify_device_remove(handler->server,
 393                                 handler->devices[i]->device);
 394                 ramdisk = handler->devices[i]->ramdisk;
 395                 talloc_free(handler->devices[i]);
 396                 talloc_free(ramdisk);
 397         }
 398
 399         talloc_free(handler->devices);
 400         handler->devices = NULL;
 401         handler->n_devices = 0;
 402         talloc_free(handler->ramdisks);
 403         handler->ramdisks = NULL;
 404         handler->n_ramdisks = 0;
 405
 406         set_env_variables(config_get());
 407
 408         device_handler_reinit_sources(handler);
 409 }
 410
 411 void device_handler_remove(struct device_handler *handler,
 412                 struct discover_device *device)
 413 {
 414         struct discover_boot_option *opt, *tmp;
 415         unsigned int i;
 416
 417         list_for_each_entry_safe(&device->boot_options, opt, tmp, list) {
 418                 if (opt == handler->default_boot_option) {
 419                         pb_log("Default option %s cancelled since device removed",
 420                                         opt->option->name);
 421                         device_handler_cancel_default(handler);
 422                         break;
 423                 }
 424         }
 425
 426         for (i = 0; i < handler->n_devices; i++)
 427                 if (handler->devices[i] == device)
 428                         break;
 429
 430         if (i == handler->n_devices) {
 431                 talloc_free(device);
 432                 return;
 433         }
 434
 435         /* Free any unresolved options, as they're currently allocated
 436          * against the handler */
 437         list_for_each_entry_safe(&handler->unresolved_boot_options,
 438                         opt, tmp, list) {
 439                 if (opt->device != device)
 440                         continue;
 441                 list_remove(&opt->list);
 442                 talloc_free(opt);
 443         }
 444
 445         /* if this is a network device, we have to unregister it from the
 446          * network code */
 447         if (device->device->type == DEVICE_TYPE_NETWORK)
 448                 network_unregister_device(handler->network, device);
 449
 450         handler->n_devices--;
 451         memmove(&handler->devices[i], &handler->devices[i + 1],
 452                 (handler->n_devices - i) * sizeof(handler->devices[0]));
 453         handler->devices = talloc_realloc(handler, handler->devices,
 454                 struct discover_device *, handler->n_devices);
 455
 456         if (device->notified)
 457                 discover_server_notify_device_remove(handler->server,
 458                                                         device->device);
 459
 460         talloc_free(device);
 461 }
 462
 463 void device_handler_status(struct device_handler *handler,
 464                 struct status *status)
 465 {
 466         discover_server_notify_boot_status(handler->server, status);
 467 }
 468
 469 static void _device_handler_vstatus(struct device_handler *handler,
 470                 enum status_type type, const char *fmt, va_list ap)
 471 {
 472         struct status status;
 473
 474         status.type = type;
 475         status.message = talloc_vasprintf(handler, fmt, ap);
 476         status.backlog = false;
 477
 478         device_handler_status(handler, &status);
 479
 480         talloc_free(status.message);
 481 }
 482
 483 static void _device_handler_vdevstatus(struct device_handler *handler,
 484                 struct discover_device *device, enum status_type type,
 485                 const char *fmt, va_list ap)
 486 {
 487         char *msg;
 488
 489         msg = talloc_asprintf(handler, "[%s] %s",
 490                         device ? device->device->id : "unknown", fmt);
 491         _device_handler_vstatus(handler, type, msg, ap);
 492         talloc_free(msg);
 493 }
 494
 495 void device_handler_status_dev_info(struct device_handler *handler,
 496                 struct discover_device *dev, const char *fmt, ...)
 497 {
 498         va_list ap;
 499
 500         va_start(ap, fmt);
 501         _device_handler_vdevstatus(handler, dev, STATUS_INFO, fmt, ap);
 502         va_end(ap);
 503 }
 504
 505 void device_handler_status_dev_err(struct device_handler *handler,
 506                 struct discover_device *dev, const char *fmt, ...)
 507 {
 508         va_list ap;
 509
 510         va_start(ap, fmt);
 511         _device_handler_vdevstatus(handler, dev, STATUS_ERROR, fmt, ap);
 512         va_end(ap);
 513 }
 514
 515 void device_handler_status_info(struct device_handler *handler,
 516                 const char *fmt, ...)
 517 {
 518         va_list ap;
 519
 520         va_start(ap, fmt);
 521         _device_handler_vstatus(handler, STATUS_INFO, fmt, ap);
 522         va_end(ap);
 523 }
 524
 525 void device_handler_status_err(struct device_handler *handler,
 526                 const char *fmt, ...)
 527 {
 528         va_list ap;
 529
 530         va_start(ap, fmt);
 531         _device_handler_vstatus(handler, STATUS_ERROR, fmt, ap);
 532         va_end(ap);
 533 }
 534
 535 void device_handler_status_download(struct device_handler *handler,
 536                 const struct process_info *procinfo,
 537                 unsigned int percentage, unsigned int size, char suffix)
 538 {
 539         struct progress_info *p, *progress = NULL;
 540         uint64_t current_converted, current = 0;
 541         const char *units = " kMGTP";
 542         unsigned long size_bytes;
 543         char *update = NULL;
 544         double total = 0;
 545         unsigned int i;
 546         int unit = 0;
 547
 548         list_for_each_entry(&handler->progress, p, list)
 549                 if (p->procinfo == procinfo)
 550                         progress = p;
 551
 552         if (!progress) {
 553                 pb_log("Registering new progress struct\n");
 554                 progress = talloc_zero(handler, struct progress_info);
 555                 if (!progress) {
 556                         pb_log("Failed to allocate room for progress struct\n");
 557                         return;
 558                 }
 559                 progress->procinfo = procinfo;
 560                 list_add(&handler->progress, &progress->list);
 561                 handler->n_progress++;
 562         }
 563
 564         size_bytes = size;
 565         for (i = 0; i < strlen(units); i++) {
 566                 if (units[i] == suffix)
 567                         break;
 568         }
 569
 570         if (i >= strlen(units)) {
 571             pb_log("Couldn't recognise suffix '%c'\n", suffix);
 572             size_bytes = 0;
 573         } else {
 574                 while (i--)
 575                         size_bytes <<= 10;
 576         }
 577
 578         progress->percentage = percentage;
 579         progress->size = size_bytes;
 580
 581         /*
 582          * Aggregate the info we have and update status. If a progress struct
 583          * has zero for both percentage and size we assume progress information
 584          * is unavailable and fall back to a generic progress message.
 585          */
 586         list_for_each_entry(&handler->progress, p, list) {
 587                 uint64_t c;
 588                 double t;
 589                 if (!p->percentage || !p->size) {
 590                         update = talloc_asprintf(handler,
 591                                         _("%u downloads in progress..."),
 592                                         handler->n_progress);
 593                         current = total = 0;
 594                         break;
 595                 }
 596
 597                 c = p->size;
 598                 t = (100 * c) / p->percentage;
 599
 600                 current += c;
 601                 total += t;
 602         }
 603
 604         if (total) {
 605                 current_converted = current;
 606                 while (current_converted >= 1000) {
 607                         current_converted >>= 10;
 608                         unit++;
 609                 }
 610                 update = talloc_asprintf(handler,
 611                                 _("%u %s downloading: %.0f%% - %lu%cB"),
 612                                 handler->n_progress,
 613                                 ngettext("item", "items", handler->n_progress),
 614                                 (current / total) * 100, current_converted,
 615                                 units[unit]);
 616         }
 617
 618         if (!update) {
 619                 pb_log("%s: failed to allocate new status\n", __func__);
 620         } else {
 621                 device_handler_status_info(handler, "%s\n", update);
 622                 talloc_free(update);
 623         }
 624 }
 625
 626 void device_handler_status_download_remove(struct device_handler *handler,
 627                 struct process_info *procinfo)
 628 {
 629         struct progress_info *p, *tmp;
 630
 631         list_for_each_entry_safe(&handler->progress, p, tmp, list)
 632                 if (p->procinfo == procinfo) {
 633                         list_remove(&p->list);
 634                         talloc_free(p);
 635                         handler->n_progress--;
 636                 }
 637 }
 638
 639 static void device_handler_boot_status_cb(void *arg, struct status *status)
 640 {
 641         device_handler_status(arg, status);
 642 }
 643
 644 static void countdown_status(struct device_handler *handler,
 645                 struct discover_boot_option *opt, unsigned int sec)
 646 {
 647         struct status status;
 648
 649         status.type = STATUS_INFO;
 650         status.message = talloc_asprintf(handler,
 651                         _("Booting in %d sec: [%s] %s"), sec,
 652                         opt->device->device->id, opt->option->name);
 653         status.backlog = false;
 654
 655         device_handler_status(handler, &status);
 656
 657         talloc_free(status.message);
 658 }
 659
 660 static int default_timeout(void *arg)
 661 {
 662         struct device_handler *handler = arg;
 663         struct discover_boot_option *opt;
 664
 665         if (!handler->default_boot_option)
 666                 return 0;
 667
 668         if (handler->pending_boot)
 669                 return 0;
 670
 671         opt = handler->default_boot_option;
 672
 673         if (handler->sec_to_boot) {
 674                 countdown_status(handler, opt, handler->sec_to_boot);
 675                 handler->sec_to_boot--;
 676                 handler->timeout_waiter = waiter_register_timeout(
 677                                                 handler->waitset, 1000,
 678                                                 default_timeout, handler);
 679                 return 0;
 680         }
 681
 682         handler->timeout_waiter = NULL;
 683
 684         pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 685
 686         platform_pre_boot();
 687
 688         handler->pending_boot = boot(handler, handler->default_boot_option,
 689                         NULL, handler->dry_run, device_handler_boot_status_cb,
 690                         handler);
 691         handler->pending_boot_is_default = true;
 692         return 0;
 693 }
 694
 695 struct {
 696         enum ipmi_bootdev       ipmi_type;
 697         enum device_type        device_type;
 698 } device_type_map[] = {
 699         { IPMI_BOOTDEV_NETWORK, DEVICE_TYPE_NETWORK },
 700         { IPMI_BOOTDEV_DISK, DEVICE_TYPE_DISK },
 701         { IPMI_BOOTDEV_DISK, DEVICE_TYPE_USB },
 702         { IPMI_BOOTDEV_CDROM, DEVICE_TYPE_OPTICAL },
 703 };
 704
 705 static bool ipmi_device_type_matches(enum ipmi_bootdev ipmi_type,
 706                 enum device_type device_type)
 707 {
 708         unsigned int i;
 709
 710         for (i = 0; i < ARRAY_SIZE(device_type_map); i++) {
 711                 if (device_type_map[i].device_type == device_type)
 712                         return device_type_map[i].ipmi_type == ipmi_type;
 713         }
 714
 715         return false;
 716 }
 717
 718 static int autoboot_option_priority(const struct config *config,
 719                                 struct discover_boot_option *opt)
 720 {
 721         enum device_type type = opt->device->device->type;
 722         const char *uuid = opt->device->uuid;
 723         struct autoboot_option *auto_opt;
 724         unsigned int i;
 725
 726         for (i = 0; i < config->n_autoboot_opts; i++) {
 727                 auto_opt = &config->autoboot_opts[i];
 728                 if (auto_opt->boot_type == BOOT_DEVICE_UUID)
 729                         if (!strcmp(auto_opt->uuid, uuid))
 730                                 return DEFAULT_PRIORITY_LOCAL_FIRST + i;
 731
 732                 if (auto_opt->boot_type == BOOT_DEVICE_TYPE)
 733                         if (auto_opt->type == type ||
 734                             auto_opt->type == DEVICE_TYPE_ANY)
 735                                 return DEFAULT_PRIORITY_LOCAL_FIRST + i;
 736         }
 737
 738         return -1;
 739 }
 740
 741 /*
 742  * We have different priorities to resolve conflicts between boot options that
 743  * report to be the default for their device. This function assigns a priority
 744  * for these options.
 745  */
 746 static enum default_priority default_option_priority(
 747                 struct discover_boot_option *opt)
 748 {
 749         const struct config *config;
 750
 751         config = config_get();
 752
 753         /* We give highest priority to IPMI-configured boot options. If
 754          * we have an IPMI bootdev configuration set, then we don't allow
 755          * any other defaults */
 756         if (config->ipmi_bootdev) {
 757                 bool ipmi_match = ipmi_device_type_matches(config->ipmi_bootdev,
 758                                 opt->device->device->type);
 759                 if (ipmi_match)
 760                         return DEFAULT_PRIORITY_REMOTE;
 761
 762                 pb_debug("handler: disabled default priority due to "
 763                                 "non-matching IPMI type %x\n",
 764                                 config->ipmi_bootdev);
 765                 return DEFAULT_PRIORITY_DISABLED;
 766         }
 767
 768         /* Next, try to match the option against the user-defined autoboot
 769          * options, either by device UUID or type. */
 770         if (config->n_autoboot_opts) {
 771                 int boot_match = autoboot_option_priority(config, opt);
 772                 if (boot_match > 0)
 773                         return boot_match;
 774         }
 775
 776         /* If the option didn't match any entry in the array, it is disabled */
 777         pb_debug("handler: disabled default priority due to "
 778                         "non-matching UUID or type\n");
 779         return DEFAULT_PRIORITY_DISABLED;
 780 }
 781
 782 static void set_default(struct device_handler *handler,
 783                 struct discover_boot_option *opt)
 784 {
 785         enum default_priority cur_prio, new_prio;
 786
 787         if (!handler->autoboot_enabled)
 788                 return;
 789
 790         pb_debug("handler: new default option: %s\n", opt->option->id);
 791
 792         new_prio = default_option_priority(opt);
 793
 794         /* Anything outside our range prevents a default boot */
 795         if (new_prio >= DEFAULT_PRIORITY_DISABLED)
 796                 return;
 797
 798         pb_debug("handler: calculated priority %d\n", new_prio);
 799
 800         /* Resolve any conflicts: if we have a new default option, it only
 801          * replaces the current if it has a higher priority. */
 802         if (handler->default_boot_option) {
 803
 804                 cur_prio = handler->default_boot_option_priority;
 805
 806                 if (new_prio < cur_prio) {
 807                         pb_log("handler: new prio %d beats "
 808                                         "old prio %d for %s\n",
 809                                         new_prio, cur_prio,
 810                                         handler->default_boot_option
 811                                                 ->option->id);
 812                         handler->default_boot_option = opt;
 813                         handler->default_boot_option_priority = new_prio;
 814                         /* extend the timeout a little, so the user sees some
 815                          * indication of the change */
 816                         handler->sec_to_boot += 2;
 817                 }
 818
 819                 return;
 820         }
 821
 822         handler->sec_to_boot = config_get()->autoboot_timeout_sec;
 823         handler->default_boot_option = opt;
 824         handler->default_boot_option_priority = new_prio;
 825
 826         pb_log("handler: boot option %s set as default, timeout %u sec.\n",
 827                opt->option->id, handler->sec_to_boot);
 828
 829         default_timeout(handler);
 830 }
 831
 832 static bool resource_is_resolved(struct resource *res)
 833 {
 834         return !res || res->resolved;
 835 }
 836
 837 /* We only use this in an assert, which will disappear if we're compiling
 838  * with NDEBUG, so we need the 'used' attribute for these builds */
 839 static bool __attribute__((used)) boot_option_is_resolved(
 840                 struct discover_boot_option *opt)
 841 {
 842         return resource_is_resolved(opt->boot_image) &&
 843                 resource_is_resolved(opt->initrd) &&
 844                 resource_is_resolved(opt->dtb) &&
 845                 resource_is_resolved(opt->args_sig_file) &&
 846                 resource_is_resolved(opt->icon);
 847 }
 848
 849 static bool resource_resolve(struct resource *res, const char *name,
 850                 struct discover_boot_option *opt,
 851                 struct device_handler *handler)
 852 {
 853         struct parser *parser = opt->source;
 854
 855         if (resource_is_resolved(res))
 856                 return true;
 857
 858         pb_debug("Attempting to resolve resource %s->%s with parser %s\n",
 859                         opt->option->id, name, parser->name);
 860         parser->resolve_resource(handler, res);
 861
 862         return res->resolved;
 863 }
 864
 865 static bool boot_option_resolve(struct discover_boot_option *opt,
 866                 struct device_handler *handler)
 867 {
 868         return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
 869                 resource_resolve(opt->initrd, "initrd", opt, handler) &&
 870                 resource_resolve(opt->dtb, "dtb", opt, handler) &&
 871                 resource_resolve(opt->args_sig_file, "args_sig_file", opt,
 872                         handler) &&
 873                 resource_resolve(opt->icon, "icon", opt, handler);
 874 }
 875
 876 static void boot_option_finalise(struct device_handler *handler,
 877                 struct discover_boot_option *opt)
 878 {
 879         assert(boot_option_is_resolved(opt));
 880
 881         /* check that the parsers haven't set any of the final data */
 882         assert(!opt->option->boot_image_file);
 883         assert(!opt->option->initrd_file);
 884         assert(!opt->option->dtb_file);
 885         assert(!opt->option->icon_file);
 886         assert(!opt->option->device_id);
 887         assert(!opt->option->args_sig_file);
 888
 889         if (opt->boot_image)
 890                 opt->option->boot_image_file = opt->boot_image->url->full;
 891         if (opt->initrd)
 892                 opt->option->initrd_file = opt->initrd->url->full;
 893         if (opt->dtb)
 894                 opt->option->dtb_file = opt->dtb->url->full;
 895         if (opt->icon)
 896                 opt->option->icon_file = opt->icon->url->full;
 897         if (opt->args_sig_file)
 898                 opt->option->args_sig_file = opt->args_sig_file->url->full;
 899
 900         opt->option->device_id = opt->device->device->id;
 901
 902         if (opt->option->is_default)
 903                 set_default(handler, opt);
 904 }
 905
 906 static void notify_boot_option(struct device_handler *handler,
 907                 struct discover_boot_option *opt)
 908 {
 909         struct discover_device *dev = opt->device;
 910
 911         if (!dev->notified)
 912                 discover_server_notify_device_add(handler->server,
 913                                                   opt->device->device);
 914         dev->notified = true;
 915         discover_server_notify_boot_option_add(handler->server, opt->option);
 916 }
 917
 918 static void process_boot_option_queue(struct device_handler *handler)
 919 {
 920         struct discover_boot_option *opt, *tmp;
 921
 922         list_for_each_entry_safe(&handler->unresolved_boot_options,
 923                         opt, tmp, list) {
 924
 925                 pb_debug("queue: attempting resolution for %s\n",
 926                                 opt->option->id);
 927
 928                 if (!boot_option_resolve(opt, handler))
 929                         continue;
 930
 931                 pb_debug("\tresolved!\n");
 932
 933                 list_remove(&opt->list);
 934                 list_add_tail(&opt->device->boot_options, &opt->list);
 935                 talloc_steal(opt->device, opt);
 936                 boot_option_finalise(handler, opt);
 937                 notify_boot_option(handler, opt);
 938         }
 939 }
 940
 941 struct discover_context *device_handler_discover_context_create(
 942                 struct device_handler *handler,
 943                 struct discover_device *device)
 944 {
 945         struct discover_context *ctx;
 946
 947         ctx = talloc_zero(handler, struct discover_context);
 948         ctx->handler = handler;
 949         ctx->device = device;
 950         list_init(&ctx->boot_options);
 951
 952         return ctx;
 953 }
 954
 955 void device_handler_add_device(struct device_handler *handler,
 956                 struct discover_device *device)
 957 {
 958         handler->n_devices++;
 959         handler->devices = talloc_realloc(handler, handler->devices,
 960                                 struct discover_device *, handler->n_devices);
 961         handler->devices[handler->n_devices - 1] = device;
 962
 963         if (device->device->type == DEVICE_TYPE_NETWORK)
 964                 network_register_device(handler->network, device);
 965 }
 966
 967 void device_handler_add_ramdisk(struct device_handler *handler,
 968                 const char *path)
 969 {
 970         struct ramdisk_device *dev;
 971         unsigned int i;
 972
 973         if (!path)
 974                 return;
 975
 976         for (i = 0; i < handler->n_ramdisks; i++)
 977                 if (!strcmp(handler->ramdisks[i]->path, path))
 978                         return;
 979
 980         dev = talloc_zero(handler, struct ramdisk_device);
 981         if (!dev) {
 982                 pb_log("Failed to allocate memory to track %s\n", path);
 983                 return;
 984         }
 985
 986         dev->path = talloc_strdup(handler, path);
 987
 988         handler->ramdisks = talloc_realloc(handler, handler->ramdisks,
 989                                 struct ramdisk_device *,
 990                                 handler->n_ramdisks + 1);
 991         if (!handler->ramdisks) {
 992                 pb_log("Failed to reallocate memory"
 993                        "- ramdisk tracking inconsistent!\n");
 994                 return;
 995         }
 996
 997         handler->ramdisks[i] = dev;
 998         i = handler->n_ramdisks++;
 999 }
1000
1001 struct ramdisk_device *device_handler_get_ramdisk(
1002                 struct device_handler *handler)
1003 {
1004         unsigned int i;
1005         char *name;
1006         dev_t id;
1007
1008         /* Check if free ramdisk exists */
1009         for (i = 0; i < handler->n_ramdisks; i++)
1010                 if (!handler->ramdisks[i]->snapshot &&
1011                     !handler->ramdisks[i]->origin &&
1012                     !handler->ramdisks[i]->base)
1013                         return handler->ramdisks[i];
1014
1015         /* Otherwise create a new one */
1016         name = talloc_asprintf(handler, "/dev/ram%d",
1017                         handler->n_ramdisks);
1018         if (!name) {
1019                 pb_debug("Failed to allocate memory to name /dev/ram%d",
1020                         handler->n_ramdisks);
1021                 return NULL;
1022         }
1023
1024         id = makedev(1, handler->n_ramdisks);
1025         if (mknod(name, S_IFBLK, id)) {
1026                 if (errno == EEXIST) {
1027                         /* We haven't yet received updates for existing
1028                          * ramdisks - add and use this one */
1029                         pb_debug("Using untracked ramdisk %s\n", name);
1030                 } else {
1031                         pb_log("Failed to create new ramdisk %s: %s\n",
1032                                name, strerror(errno));
1033                         return NULL;
1034                 }
1035         }
1036         device_handler_add_ramdisk(handler, name);
1037         talloc_free(name);
1038
1039         return handler->ramdisks[i];
1040 }
1041
1042 void device_handler_release_ramdisk(struct discover_device *device)
1043 {
1044         struct ramdisk_device *ramdisk = device->ramdisk;
1045
1046         talloc_free(ramdisk->snapshot);
1047         talloc_free(ramdisk->origin);
1048         talloc_free(ramdisk->base);
1049
1050         ramdisk->snapshot = ramdisk->origin = ramdisk->base = NULL;
1051         ramdisk->sectors = 0;
1052
1053         device->ramdisk = NULL;
1054 }
1055
1056 /* Start discovery on a hotplugged device. The device will be in our devices
1057  * array, but has only just been initialised by the hotplug source.
1058  */
1059 int device_handler_discover(struct device_handler *handler,
1060                 struct discover_device *dev)
1061 {
1062         struct discover_context *ctx;
1063         int rc;
1064
1065         device_handler_status_dev_info(handler, dev,
1066                 /*
1067                  * TRANSLATORS: this string will be passed the type of the
1068                  * device (eg "disk" or "network"), which will be translated
1069                  * accordingly.
1070                  */
1071                 _("Processing new %s device"),
1072                 device_type_display_name(dev->device->type));
1073
1074         /* create our context */
1075         ctx = device_handler_discover_context_create(handler, dev);
1076
1077         rc = mount_device(dev);
1078         if (rc)
1079                 goto out;
1080
1081         /* add this device to our system info */
1082         system_info_register_blockdev(dev->device->id, dev->uuid,
1083                         dev->mount_path);
1084
1085         /* run the parsers. This will populate the ctx's boot_option list. */
1086         iterate_parsers(ctx);
1087
1088         /* add discovered stuff to the handler */
1089         device_handler_discover_context_commit(handler, ctx);
1090
1091         process_boot_option_queue(handler);
1092 out:
1093         talloc_unlink(handler, ctx);
1094
1095         return 0;
1096 }
1097
1098 /* Incoming dhcp event */
1099 int device_handler_dhcp(struct device_handler *handler,
1100                 struct discover_device *dev, struct event *event)
1101 {
1102         struct discover_context *ctx;
1103
1104         device_handler_status_dev_info(handler, dev,
1105                         _("Processing DHCP lease response (ip: %s)"),
1106                         event_get_param(event, "ip"));
1107
1108         pending_network_jobs_start();
1109
1110         /* create our context */
1111         ctx = device_handler_discover_context_create(handler, dev);
1112         talloc_steal(ctx, event);
1113         ctx->event = event;
1114
1115         iterate_parsers(ctx);
1116
1117         device_handler_discover_context_commit(handler, ctx);
1118
1119         talloc_unlink(handler, ctx);
1120
1121         return 0;
1122 }
1123
1124 static struct discover_boot_option *find_boot_option_by_id(
1125                 struct device_handler *handler, const char *id)
1126 {
1127         unsigned int i;
1128
1129         for (i = 0; i < handler->n_devices; i++) {
1130                 struct discover_device *dev = handler->devices[i];
1131                 struct discover_boot_option *opt;
1132
1133                 list_for_each_entry(&dev->boot_options, opt, list)
1134                         if (!strcmp(opt->option->id, id))
1135                                 return opt;
1136         }
1137
1138         return NULL;
1139 }
1140
1141 void device_handler_boot(struct device_handler *handler,
1142                 struct boot_command *cmd)
1143 {
1144         struct discover_boot_option *opt = NULL;
1145
1146         if (cmd->option_id && strlen(cmd->option_id))
1147                 opt = find_boot_option_by_id(handler, cmd->option_id);
1148
1149         if (handler->pending_boot)
1150                 boot_cancel(handler->pending_boot);
1151
1152         platform_pre_boot();
1153
1154         handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
1155                         device_handler_boot_status_cb, handler);
1156         handler->pending_boot_is_default = false;
1157 }
1158
1159 void device_handler_cancel_default(struct device_handler *handler)
1160 {
1161         if (handler->timeout_waiter)
1162                 waiter_remove(handler->timeout_waiter);
1163
1164         handler->timeout_waiter = NULL;
1165         handler->autoboot_enabled = false;
1166
1167         /* we only send status if we had a default boot option queued */
1168         if (!handler->default_boot_option)
1169                 return;
1170
1171         pb_log("Cancelling default boot option\n");
1172
1173         if (handler->pending_boot && handler->pending_boot_is_default) {
1174                 boot_cancel(handler->pending_boot);
1175                 handler->pending_boot = NULL;
1176                 handler->pending_boot_is_default = false;
1177         }
1178
1179         handler->default_boot_option = NULL;
1180
1181         device_handler_status_info(handler, _("Default boot cancelled"));
1182 }
1183
1184 void device_handler_update_config(struct device_handler *handler,
1185                 struct config *config)
1186 {
1187         int rc;
1188
1189         rc = config_set(config);
1190         if (rc)
1191                 return;
1192
1193         discover_server_notify_config(handler->server, config);
1194         device_handler_update_lang(config->lang);
1195         device_handler_reinit(handler);
1196 }
1197
1198 static char *device_from_addr(void *ctx, struct pb_url *url)
1199 {
1200         char *ipaddr, *buf, *tok, *dev = NULL;
1201         const char *delim = " ";
1202         struct sockaddr_in *ip;
1203         struct sockaddr_in si;
1204         struct addrinfo *res;
1205         struct process *p;
1206         int rc;
1207
1208         /* Note: IPv4 only */
1209         rc = inet_pton(AF_INET, url->host, &(si.sin_addr));
1210         if (rc > 0) {
1211                 ipaddr = url->host;
1212         } else {
1213                 /* need to turn hostname into a valid IP */
1214                 rc = getaddrinfo(url->host, NULL, NULL, &res);
1215                 if (rc) {
1216                         pb_debug("%s: Invalid URL\n",__func__);
1217                         return NULL;
1218                 }
1219                 ipaddr = talloc_array(ctx,char,INET_ADDRSTRLEN);
1220                 ip = (struct sockaddr_in *) res->ai_addr;
1221                 inet_ntop(AF_INET, &(ip->sin_addr), ipaddr, INET_ADDRSTRLEN);
1222                 freeaddrinfo(res);
1223         }
1224
1225         const char *argv[] = {
1226                 pb_system_apps.ip,
1227                 "route", "show", "to", "match",
1228                 ipaddr,
1229                 NULL
1230         };
1231
1232         p = process_create(ctx);
1233
1234         p->path = pb_system_apps.ip;
1235         p->argv = argv;
1236         p->keep_stdout = true;
1237
1238         rc = process_run_sync(p);
1239
1240         if (rc || p->exit_status) {
1241                 /* ip has complained for some reason; most likely
1242                  * there is no route to the host - bail out */
1243                 pb_debug("%s: `ip` returns non-zero exit status\n", __func__);
1244                 pb_debug("ip buf: %s\n", p->stdout_buf);
1245                 process_release(p);
1246                 return NULL;
1247         }
1248
1249         buf = p->stdout_buf;
1250         /* If a route is found, ip-route output will be of the form
1251          * "... dev DEVNAME ... " */
1252         tok = strtok(buf, delim);
1253         while (tok) {
1254                 if (!strcmp(tok, "dev")) {
1255                         tok = strtok(NULL, delim);
1256                         dev = talloc_strdup(ctx, tok);
1257                         break;
1258                 }
1259                 tok = strtok(NULL, delim);
1260         }
1261
1262         process_release(p);
1263         if (dev)
1264                 pb_debug("%s: Found interface '%s'\n", __func__,dev);
1265         return dev;
1266 }
1267
1268 static void process_url_cb(struct load_url_result *result, void *data)
1269 {
1270         struct device_handler *handler;
1271         struct discover_context *ctx;
1272         struct discover_device *dev;
1273         struct event *event = data;
1274         const char *mac;
1275
1276         if (result->status != LOAD_OK) {
1277                 pb_log("%s: Load failed for %s\n", __func__, result->url->full);
1278                 return;
1279         }
1280
1281         if (!event)
1282                 return;
1283
1284         handler = talloc_parent(event);
1285         if (!handler)
1286                 return;
1287
1288         event->device = device_from_addr(event, result->url);
1289         if (!event->device) {
1290                 pb_log("Downloaded a file but can't find its interface - pretending it was local\n");
1291                 event->device = talloc_asprintf(event, "local");
1292         }
1293
1294         mac = event_get_param(event, "mac");
1295         char *url = talloc_asprintf(event, "file://%s", result->local);
1296         event_set_param(event, "pxeconffile", url);
1297
1298         dev = discover_device_create(handler, mac, event->device);
1299         ctx = device_handler_discover_context_create(handler, dev);
1300         talloc_steal(ctx, event);
1301         ctx->event = event;
1302
1303         iterate_parsers(ctx);
1304
1305         device_handler_discover_context_commit(handler, ctx);
1306
1307         talloc_unlink(handler, ctx);
1308 }
1309
1310 void device_handler_process_url(struct device_handler *handler,
1311                 const char *url, const char *mac, const char *ip)
1312 {
1313         struct discover_context *ctx;
1314         struct discover_device *dev;
1315         bool allow_async = false;
1316         struct pb_url *pb_url;
1317         struct event *event;
1318
1319         event = talloc_zero(handler, struct event);
1320         event->type = EVENT_TYPE_USER;
1321         event->action = EVENT_ACTION_URL;
1322
1323         pb_url = pb_url_parse(event, url);
1324         if (!pb_url || (pb_url->scheme != pb_url_file && !pb_url->host)) {
1325                 device_handler_status_err(handler, _("Invalid config URL!"));
1326                 talloc_free(event);
1327                 return;
1328         }
1329
1330         if (url[strlen(url) - 1] == '/') {
1331                 event_set_param(event, "pxepathprefix", url);
1332                 event_set_param(event, "mac", mac);
1333                 event_set_param(event, "ip", ip);
1334                 event->device = device_from_addr(event, pb_url);
1335                 if (!event->device) {
1336                         device_handler_status_err(handler,
1337                                         _("Unable to route to host %s"),
1338                                         pb_url->host);
1339                         talloc_free(event);
1340                         return;
1341                 }
1342         } else {
1343                 event_set_param(event, "pxeconffile", url);
1344                 allow_async = true;
1345         }
1346
1347         if (pb_url->scheme == pb_url_file)
1348                 event->device = talloc_asprintf(event, "local");
1349         else if (allow_async) {
1350                 /* If file is remote load asynchronously before passing to
1351                  * parser. This allows us to wait for network to be available */
1352                 if (!load_url_async(handler, pb_url, process_url_cb, event,
1353                                         NULL, handler)) {
1354                         pb_log("Failed to load url %s\n", pb_url->full);
1355                         device_handler_status_err(handler, _("Failed to load URL!"));
1356                         talloc_free(event);
1357                 }
1358                 return;
1359         }
1360
1361         /* If path is local we can parse straight away */
1362
1363         dev = discover_device_create(handler, mac, event->device);
1364         if (pb_url->scheme == pb_url_file)
1365                 dev->device->type = DEVICE_TYPE_ANY;
1366         ctx = device_handler_discover_context_create(handler, dev);
1367         talloc_steal(ctx, event);
1368         ctx->event = event;
1369
1370         iterate_parsers(ctx);
1371
1372         device_handler_discover_context_commit(handler, ctx);
1373
1374         talloc_unlink(handler, ctx);
1375 }
1376
1377 #ifndef PETITBOOT_TEST
1378
1379 /**
1380  * context_commit - Commit a temporary discovery context to the handler,
1381  * and notify the clients about any new options / devices
1382  */
1383 void device_handler_discover_context_commit(struct device_handler *handler,
1384                 struct discover_context *ctx)
1385 {
1386         struct discover_device *dev = ctx->device;
1387         struct discover_boot_option *opt, *tmp;
1388
1389         if (!device_lookup_by_uuid(handler, dev->uuid))
1390                 device_handler_add_device(handler, dev);
1391
1392         /* move boot options from the context to the device */
1393         list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
1394                 list_remove(&opt->list);
1395
1396                 /* All boot options need at least a kernel image */
1397                 if (!opt->boot_image || !opt->boot_image->url) {
1398                         pb_log("boot option %s is missing boot image, ignoring\n",
1399                                 opt->option->id);
1400                         talloc_free(opt);
1401                         continue;
1402                 }
1403
1404                 if (boot_option_resolve(opt, handler)) {
1405                         pb_log("boot option %s is resolved, "
1406                                         "sending to clients\n",
1407                                         opt->option->id);
1408                         list_add_tail(&dev->boot_options, &opt->list);
1409                         talloc_steal(dev, opt);
1410                         boot_option_finalise(handler, opt);
1411                         notify_boot_option(handler, opt);
1412                 } else {
1413                         if (!opt->source->resolve_resource) {
1414                                 pb_log("parser %s gave us an unresolved "
1415                                         "resource (%s), but no way to "
1416                                         "resolve it\n",
1417                                         opt->source->name, opt->option->id);
1418                                 talloc_free(opt);
1419                         } else {
1420                                 pb_log("boot option %s is unresolved, "
1421                                                 "adding to queue\n",
1422                                                 opt->option->id);
1423                                 list_add(&handler->unresolved_boot_options,
1424                                                 &opt->list);
1425                                 talloc_steal(handler, opt);
1426                         }
1427                 }
1428         }
1429 }
1430
1431 static void device_handler_update_lang(const char *lang)
1432 {
1433         const char *cur_lang;
1434
1435         if (!lang)
1436                 return;
1437
1438         cur_lang = setlocale(LC_ALL, NULL);
1439         if (cur_lang && !strcmp(cur_lang, lang))
1440                 return;
1441
1442         setlocale(LC_ALL, lang);
1443 }
1444
1445 static int device_handler_init_sources(struct device_handler *handler)
1446 {
1447         /* init our device sources: udev, network and user events */
1448         handler->network = network_init(handler, handler->waitset,
1449                         handler->dry_run);
1450         if (!handler->network)
1451                 return -1;
1452
1453         handler->udev = udev_init(handler, handler->waitset);
1454         if (!handler->udev)
1455                 return -1;
1456
1457         handler->user_event = user_event_init(handler, handler->waitset);
1458         if (!handler->user_event)
1459                 return -1;
1460
1461         return 0;
1462 }
1463
1464 static void device_handler_reinit_sources(struct device_handler *handler)
1465 {
1466         /* if we haven't initialised sources previously (becuase we started in
1467          * safe mode), then init once here. */
1468         if (!(handler->udev || handler->network || handler->user_event)) {
1469                 device_handler_init_sources(handler);
1470                 return;
1471         }
1472
1473         system_info_reinit();
1474
1475         network_shutdown(handler->network);
1476         handler->network = network_init(handler, handler->waitset,
1477                         handler->dry_run);
1478
1479         udev_reinit(handler->udev);
1480 }
1481
1482 static inline const char *get_device_path(struct discover_device *dev)
1483 {
1484         return dev->ramdisk ? dev->ramdisk->snapshot : dev->device_path;
1485 }
1486
1487 static char *check_subvols(struct discover_device *dev)
1488 {
1489         const char *fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1490         struct stat sb;
1491         char *path;
1492         int rc;
1493
1494         if (strncmp(fstype, "btrfs", strlen("btrfs")))
1495                 return dev->mount_path;
1496
1497         /* On btrfs a device's root may be under a subvolume path */
1498         path = join_paths(dev, dev->mount_path, "@");
1499         rc = stat(path, &sb);
1500         if (!rc && S_ISDIR(sb.st_mode)) {
1501                 pb_debug("Using '%s' for btrfs root path\n", path);
1502                 return path;
1503         }
1504
1505         talloc_free(path);
1506         return dev->mount_path;
1507 }
1508
1509 static bool check_existing_mount(struct discover_device *dev)
1510 {
1511         struct stat devstat, mntstat;
1512         const char *device_path;
1513         struct mntent *mnt;
1514         FILE *fp;
1515         int rc;
1516
1517         device_path = get_device_path(dev);
1518
1519         rc = stat(device_path, &devstat);
1520         if (rc) {
1521                 pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
1522                 return false;
1523         }
1524
1525         if (!S_ISBLK(devstat.st_mode)) {
1526                 pb_debug("%s: %s isn't a block device?\n", __func__,
1527                                 dev->device_path);
1528                 return false;
1529         }
1530
1531         fp = fopen("/proc/self/mounts", "r");
1532
1533         for (;;) {
1534                 mnt = getmntent(fp);
1535                 if (!mnt)
1536                         break;
1537
1538                 if (!mnt->mnt_fsname || mnt->mnt_fsname[0] != '/')
1539                         continue;
1540
1541                 rc = stat(mnt->mnt_fsname, &mntstat);
1542                 if (rc)
1543                         continue;
1544
1545                 if (!S_ISBLK(mntstat.st_mode))
1546                         continue;
1547
1548                 if (mntstat.st_rdev == devstat.st_rdev) {
1549                         dev->mount_path = talloc_strdup(dev, mnt->mnt_dir);
1550                         dev->root_path = check_subvols(dev);
1551                         dev->mounted_rw = !!hasmntopt(mnt, "rw");
1552                         dev->mounted = true;
1553                         dev->unmount = false;
1554
1555                         pb_debug("%s: %s is already mounted (r%c) at %s\n",
1556                                         __func__, dev->device_path,
1557                                         dev->mounted_rw ? 'w' : 'o',
1558                                         mnt->mnt_dir);
1559                         break;
1560                 }
1561         }
1562
1563         fclose(fp);
1564
1565         return mnt != NULL;
1566 }
1567
1568 /*
1569  * Attempt to mount a filesystem safely, while handling certain filesytem-
1570  * specific options
1571  */
1572 static int try_mount(const char *device_path, const char *mount_path,
1573                              const char *fstype, unsigned long flags,
1574                              bool have_snapshot)
1575 {
1576         const char *fs, *safe_opts;
1577         int rc;
1578
1579         /* Mount ext3 as ext4 instead so 'norecovery' can be used */
1580         if (strncmp(fstype, "ext3", strlen("ext3")) == 0) {
1581                 pb_debug("Mounting ext3 filesystem as ext4\n");
1582                 fs = "ext4";
1583         } else
1584                 fs = fstype;
1585
1586         if (strncmp(fs, "xfs", strlen("xfs")) == 0 ||
1587             strncmp(fs, "ext4", strlen("ext4")) == 0)
1588                 safe_opts = "norecovery";
1589         else
1590                 safe_opts = NULL;
1591
1592         errno = 0;
1593         /* If no snapshot is available don't attempt recovery */
1594         if (!have_snapshot)
1595                 return mount(device_path, mount_path, fs, flags, safe_opts);
1596
1597         rc = mount(device_path, mount_path, fs, flags, NULL);
1598
1599         if (!rc)
1600                 return rc;
1601
1602         /* Mounting failed; some filesystems will fail to mount if a recovery
1603          * journal exists (eg. cross-endian XFS), so try again with norecovery
1604          * where that option is available.
1605          * If mounting read-write just return the error as norecovery is not a
1606          * valid option */
1607         if ((flags & MS_RDONLY) != MS_RDONLY || !safe_opts)
1608                 return rc;
1609
1610         errno = 0;
1611         return mount(device_path, mount_path, fs, flags, safe_opts);
1612 }
1613
1614 static int mount_device(struct discover_device *dev)
1615 {
1616         const char *fstype, *device_path;
1617         int rc;
1618
1619         if (!dev->device_path)
1620                 return -1;
1621
1622         if (dev->mounted)
1623                 return 0;
1624
1625         if (check_existing_mount(dev))
1626                 return 0;
1627
1628         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1629         if (!fstype)
1630                 return 0;
1631
1632         dev->mount_path = join_paths(dev, mount_base(),
1633                                         dev->device_path);
1634
1635         if (pb_mkdir_recursive(dev->mount_path)) {
1636                 pb_log("couldn't create mount directory %s: %s\n",
1637                                 dev->mount_path, strerror(errno));
1638                 goto err_free;
1639         }
1640
1641         device_path = get_device_path(dev);
1642
1643         pb_log("mounting device %s read-only\n", dev->device_path);
1644         rc = try_mount(device_path, dev->mount_path, fstype,
1645                        MS_RDONLY | MS_SILENT, dev->ramdisk);
1646
1647         if (!rc) {
1648                 dev->mounted = true;
1649                 dev->mounted_rw = false;
1650                 dev->unmount = true;
1651                 dev->root_path = check_subvols(dev);
1652                 return 0;
1653         }
1654
1655         pb_log("couldn't mount device %s: mount failed: %s\n",
1656                         device_path, strerror(errno));
1657
1658         /* If mount fails clean up any snapshot */
1659         devmapper_destroy_snapshot(dev);
1660
1661         pb_rmdir_recursive(mount_base(), dev->mount_path);
1662 err_free:
1663         talloc_free(dev->mount_path);
1664         dev->mount_path = NULL;
1665         return -1;
1666 }
1667
1668 static int umount_device(struct discover_device *dev)
1669 {
1670         const char *device_path;
1671         int rc;
1672
1673         if (!dev->mounted || !dev->unmount)
1674                 return 0;
1675
1676         device_path = get_device_path(dev);
1677
1678         pb_log("unmounting device %s\n", device_path);
1679         rc = umount(dev->mount_path);
1680         if (rc)
1681                 return -1;
1682
1683         dev->mounted = false;
1684         devmapper_destroy_snapshot(dev);
1685
1686         pb_rmdir_recursive(mount_base(), dev->mount_path);
1687
1688         talloc_free(dev->mount_path);
1689         dev->mount_path = NULL;
1690         dev->root_path = NULL;
1691
1692         return 0;
1693 }
1694
1695 int device_request_write(struct discover_device *dev, bool *release)
1696 {
1697         const char *fstype, *device_path;
1698         const struct config *config;
1699         int rc;
1700
1701         *release = false;
1702
1703         config = config_get();
1704         if (!config->allow_writes)
1705                 return -1;
1706
1707         if (!dev->mounted)
1708                 return -1;
1709
1710         if (dev->mounted_rw)
1711                 return 0;
1712
1713         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1714
1715         device_path = get_device_path(dev);
1716
1717         pb_log("remounting device %s read-write\n", device_path);
1718
1719         rc = umount(dev->mount_path);
1720         if (rc) {
1721                 pb_log("Failed to unmount %s: %s\n",
1722                        dev->mount_path, strerror(errno));
1723                 return -1;
1724         }
1725
1726         rc = try_mount(device_path, dev->mount_path, fstype,
1727                        MS_SILENT, dev->ramdisk);
1728         if (rc)
1729                 goto mount_ro;
1730
1731         dev->mounted_rw = true;
1732         *release = true;
1733         return 0;
1734
1735 mount_ro:
1736         pb_log("Unable to remount device %s read-write: %s\n",
1737                device_path, strerror(errno));
1738         rc = try_mount(device_path, dev->mount_path, fstype,
1739                        MS_RDONLY | MS_SILENT, dev->ramdisk);
1740         if (rc)
1741                 pb_log("Unable to recover mount for %s: %s\n",
1742                        device_path, strerror(errno));
1743         return -1;
1744 }
1745
1746 void device_release_write(struct discover_device *dev, bool release)
1747 {
1748         const char *fstype, *device_path;
1749
1750         if (!release)
1751                 return;
1752
1753         device_path = get_device_path(dev);
1754
1755         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1756
1757         pb_log("remounting device %s read-only\n", device_path);
1758
1759         if (umount(dev->mount_path)) {
1760                 pb_log("Failed to unmount %s\n", dev->mount_path);
1761                 return;
1762         }
1763         dev->mounted_rw = dev->mounted = false;
1764
1765         if (dev->ramdisk) {
1766                 devmapper_merge_snapshot(dev);
1767                 /* device_path becomes stale after merge */
1768                 device_path = get_device_path(dev);
1769         }
1770
1771         if (try_mount(device_path, dev->mount_path, fstype,
1772                        MS_RDONLY | MS_SILENT, dev->ramdisk))
1773                 pb_log("Failed to remount %s read-only: %s\n",
1774                        device_path, strerror(errno));
1775         else
1776                 dev->mounted = true;
1777 }
1778
1779 void device_sync_snapshots(struct device_handler *handler, const char *device)
1780 {
1781         struct discover_device *dev = NULL;
1782         unsigned int i;
1783
1784         if (device) {
1785                 /* Find matching device and sync */
1786                 dev = device_lookup_by_name(handler, device);
1787                 if (!dev) {
1788                         pb_log("%s: device name '%s' unrecognised\n",
1789                                 __func__, device);
1790                         return;
1791                 }
1792                 if (dev->ramdisk)
1793                         device_release_write(dev, true);
1794                 else
1795                         pb_log("%s has no snapshot to merge, skipping\n",
1796                                 dev->device->id);
1797                 return;
1798         }
1799
1800         /* Otherwise sync all relevant devices */
1801         for (i = 0; i < handler->n_devices; i++) {
1802                 dev = handler->devices[i];
1803                 if (dev->device->type != DEVICE_TYPE_DISK &&
1804                         dev->device->type != DEVICE_TYPE_USB)
1805                         continue;
1806                 if (dev->ramdisk)
1807                         device_release_write(dev, true);
1808                 else
1809                         pb_log("%s has no snapshot to merge, skipping\n",
1810                                 dev->device->id);
1811         }
1812 }
1813
1814 #else
1815
1816 void device_handler_discover_context_commit(
1817                 struct device_handler *handler __attribute__((unused)),
1818                 struct discover_context *ctx __attribute__((unused)))
1819 {
1820         pb_log("%s stubbed out for test cases\n", __func__);
1821 }
1822
1823 static void device_handler_update_lang(const char *lang __attribute__((unused)))
1824 {
1825 }
1826
1827 static int device_handler_init_sources(
1828                 struct device_handler *handler __attribute__((unused)))
1829 {
1830         return 0;
1831 }
1832
1833 static void device_handler_reinit_sources(
1834                 struct device_handler *handler __attribute__((unused)))
1835 {
1836 }
1837
1838 static int umount_device(struct discover_device *dev __attribute__((unused)))
1839 {
1840         return 0;
1841 }
1842
1843 static int __attribute__((unused)) mount_device(
1844                 struct discover_device *dev __attribute__((unused)))
1845 {
1846         return 0;
1847 }
1848
1849 int device_request_write(struct discover_device *dev __attribute__((unused)),
1850                 bool *release)
1851 {
1852         *release = true;
1853         return 0;
1854 }
1855
1856 void device_release_write(struct discover_device *dev __attribute__((unused)),
1857         bool release __attribute__((unused)))
1858 {
1859 }
1860
1861 void device_sync_snapshots(
1862                 struct device_handler *handler __attribute__((unused)),
1863                 const char *device __attribute__((unused)))
1864 {
1865 }
1866
1867 #endif