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