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