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