summaryrefslogtreecommitdiffstats
path: root/discover/device-handler.c
blob: 23961249ff595b857b327a34f025e31c64a97d1d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699

#include <assert.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <talloc/talloc.h>
#include <list/list.h>
#include <log/log.h>
#include <types/types.h>
#include <system/system.h>
#include <url/url.h>

#include "device-handler.h"
#include "discover-server.h"
#include "event.h"
#include "parser.h"
#include "resource.h"
#include "udev.h"
#include "paths.h"
#include "boot.h"

struct device_handler {
	struct discover_server	*server;
	int			dry_run;

	struct discover_device	**devices;
	unsigned int		n_devices;

	struct list		unresolved_boot_options;
};

static bool resource_is_resolved(struct resource *res)
{
	return !res || res->resolved;
}

/* We only use this in an assert, which will disappear if we're compiling
 * with NDEBUG, so we need the 'used' attribute for these builds */
static bool __attribute__((used)) boot_option_is_resolved(
		struct discover_boot_option *opt)
{
	return resource_is_resolved(opt->boot_image) &&
		resource_is_resolved(opt->initrd) &&
		resource_is_resolved(opt->icon);
}

static bool resource_resolve(struct resource *res, struct parser *parser,
		struct device_handler *handler)
{
	if (resource_is_resolved(res))
		return true;

	parser->resolve_resource(handler, res);

	return res->resolved;
}

static bool boot_option_resolve(struct discover_boot_option *opt,
		struct device_handler *handler)
{
	return resource_resolve(opt->boot_image, opt->source, handler) &&
		resource_resolve(opt->initrd, opt->source, handler) &&
		resource_resolve(opt->icon, opt->source, handler);
}

static void boot_option_finalise(struct discover_boot_option *opt)
{
	assert(boot_option_is_resolved(opt));

	/* check that the parsers haven't set any of the final data */
	assert(!opt->option->boot_image_file);
	assert(!opt->option->initrd_file);
	assert(!opt->option->icon_file);
	assert(!opt->option->device_id);

	if (opt->boot_image)
		opt->option->boot_image_file = opt->boot_image->url->full;
	if (opt->initrd)
		opt->option->initrd_file = opt->initrd->url->full;
	if (opt->icon)
		opt->option->icon_file = opt->icon->url->full;

	opt->option->device_id = opt->device->device->id;
}

static void process_boot_option_queue(struct device_handler *handler)
{
	struct discover_boot_option *opt, *tmp;

	list_for_each_entry_safe(&handler->unresolved_boot_options,
			opt, tmp, list) {

		if (!boot_option_resolve(opt, handler))
			continue;

		list_remove(&opt->list);
		list_add(&opt->device->boot_options, &opt->list);
		talloc_steal(opt->device, opt);
		boot_option_finalise(opt);
		discover_server_notify_boot_option_add(handler->server,
							opt->option);
	}
}

/**
 * context_commit - Commit a temporary discovery context to the handler,
 * and notify the clients about any new options / devices
 */
static void context_commit(struct device_handler *handler,
		struct discover_context *ctx)
{
	struct discover_device *dev = ctx->device;
	struct discover_boot_option *opt, *tmp;
	unsigned int i, existing_device = 0;

	/* do we already have this device? */
	for (i = 0; i < handler->n_devices; i++) {
		if (ctx->device == handler->devices[i]) {
			existing_device = 1;
			break;
		}
	}

	/* if not already present, add the device to the handler's array */
	if (!existing_device) {
		handler->n_devices++;
		handler->devices = talloc_realloc(handler, handler->devices,
			struct discover_device *, handler->n_devices);
		handler->devices[handler->n_devices - 1] = dev;
		talloc_steal(handler, dev);

		discover_server_notify_device_add(handler->server, dev->device);

		/* this new device might be able to resolve existing boot
		 * options */
		process_boot_option_queue(handler);
	}


	/* move boot options from the context to the device */
	list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
		list_remove(&opt->list);

		if (boot_option_resolve(opt, handler)) {
			list_add(&dev->boot_options, &opt->list);
			talloc_steal(dev, opt);
			boot_option_finalise(opt);
			discover_server_notify_boot_option_add(handler->server,
								opt->option);
		} else {
			if (!opt->source->resolve_resource) {
				pb_log("parser %s gave us an unresolved "
					"resource (%s), but no way to "
					"resolve it\n",
					opt->source->name, opt->option->id);
				talloc_free(opt);
			} else {
				pb_log("boot option %s is unresolved, "
						"adding to queue\n",
						opt->option->id);
				list_add(&handler->unresolved_boot_options,
						&opt->list);
				talloc_steal(handler, opt);
			}
		}
	}
}

void discover_context_add_boot_option(struct discover_context *ctx,
		struct discover_boot_option *boot_option)
{
	boot_option->source = ctx->parser;
	list_add_tail(&ctx->boot_options, &boot_option->list);
	talloc_steal(ctx, boot_option);
}

/**
 * device_handler_remove - Remove a device from the handler device array.
 */

static void device_handler_remove(struct device_handler *handler,
	struct discover_device *device)
{
	unsigned int i;

	for (i = 0; i < handler->n_devices; i++)
		if (handler->devices[i] == device)
			break;

	if (i == handler->n_devices) {
		assert(0 && "unknown device");
		return;
	}

	handler->n_devices--;
	memmove(&handler->devices[i], &handler->devices[i + 1],
		(handler->n_devices - i) * sizeof(handler->devices[0]));
	handler->devices = talloc_realloc(handler, handler->devices,
		struct discover_device *, handler->n_devices);

	discover_server_notify_device_remove(handler->server, device->device);

	talloc_free(device);
}

/**
 * device_handler_get_device_count - Get the count of current handler devices.
 */

int device_handler_get_device_count(const struct device_handler *handler)
{
	return handler->n_devices;
}

/**
 * device_handler_get_device - Get a handler device by index.
 */

const struct discover_device *device_handler_get_device(
	const struct device_handler *handler, unsigned int index)
{
	if (index >= handler->n_devices) {
		assert(0 && "bad index");
		return NULL;
	}

	return handler->devices[index];
}

static int mount_device(struct discover_device *dev)
{
	const char *argv[6];

	if (!dev->device_path)
		return -1;

	if (!dev->mount_path)
		dev->mount_path = join_paths(dev, mount_base(),
						dev->device_path);

	if (pb_mkdir_recursive(dev->mount_path))
		pb_log("couldn't create mount directory %s: %s\n",
				dev->mount_path, strerror(errno));

	argv[0] = pb_system_apps.mount;
	argv[1] = dev->device_path;
	argv[2] = dev->mount_path;
	argv[3] = "-o";
	argv[4] = "ro";
	argv[5] = NULL;

	if (pb_run_cmd(argv, 1, 0)) {

		/* Retry mount without ro option. */

		argv[0] = pb_system_apps.mount;
		argv[1] = dev->device_path;
		argv[2] = dev->mount_path;
		argv[3] = NULL;

		if (pb_run_cmd(argv, 1, 0))
			goto out_rmdir;
	}

	return 0;

out_rmdir:
	pb_rmdir_recursive(mount_base(), dev->mount_path);
	return -1;
}

static int umount_device(struct discover_device *dev)
{
	int status;
	pid_t pid;

	if (!dev->mount_path)
		return 0;

	pid = fork();
	if (pid == -1) {
		pb_log("%s: fork failed: %s\n", __func__, strerror(errno));
		return -1;
	}

	if (pid == 0) {
		execl(pb_system_apps.umount, pb_system_apps.umount,
						dev->mount_path, NULL);
		exit(EXIT_FAILURE);
	}

	if (waitpid(pid, &status, 0) == -1) {
		pb_log("%s: waitpid failed: %s\n", __func__,
				strerror(errno));
		return -1;
	}

	if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
		return -1;

	pb_rmdir_recursive(mount_base(), dev->mount_path);

	return 0;
}

static struct discover_device *find_device(struct device_handler *handler,
		const char *id)
{
	struct discover_device *dev;
	unsigned int i;

	for (i = 0; i < handler->n_devices; i++) {
		dev = handler->devices[i];
		if (!strcmp(dev->device->id, id))
			return dev;
	}

	return NULL;
}

static int destroy_device(void *arg)
{
	struct discover_device *dev = arg;

	umount_device(dev);

	return 0;
}

static struct discover_device *discover_device_create(
		struct device_handler *handler,
		struct discover_context *ctx,
		struct event *event)
{
	struct discover_device *dev;
	const char *devname;

	dev = find_device(handler, event->device);
	if (dev)
		return dev;

	dev = talloc_zero(ctx, struct discover_device);
	dev->device = talloc_zero(dev, struct device);
	list_init(&dev->boot_options);

	devname = event_get_param(ctx->event, "DEVNAME");
	if (devname)
		dev->device_path = talloc_strdup(dev, devname);

	dev->device->id = talloc_strdup(dev, event->device);

	talloc_set_destructor(dev, destroy_device);

	return dev;
}

struct discover_boot_option *discover_boot_option_create(
		struct discover_context *ctx,
		struct discover_device *device)
{
	struct discover_boot_option *opt;

	opt = talloc_zero(ctx, struct discover_boot_option);
	opt->option = talloc_zero(opt, struct boot_option);
	opt->device = device;

	return opt;
}


static int handle_add_udev_event(struct device_handler *handler,
		struct event *event)
{
	struct discover_context *ctx;
	struct discover_device *dev;
	const char *param;
	int rc;

	/* create our context */
	ctx = talloc(handler, struct discover_context);
	ctx->event = event;
	list_init(&ctx->boot_options);

	/* create our top-level device */
	dev = discover_device_create(handler, ctx, event);

	ctx->device = dev;

	/* try to parse UUID and labels */
	param = event_get_param(ctx->event, "ID_FS_UUID");
	if (param)
		dev->uuid = talloc_strdup(dev, param);

	param = event_get_param(ctx->event, "ID_FS_LABEL");
	if (param)
		dev->label = talloc_strdup(dev, param);

	rc = mount_device(dev);
	if (rc) {
		talloc_free(ctx);
		return 0;
	}

	/* run the parsers. This will populate the ctx's boot_option list. */
	iterate_parsers(ctx, CONF_METHOD_LOCAL_FILE);

	/* add discovered stuff to the handler */
	context_commit(handler, ctx);

	talloc_free(ctx);

	return 0;
}

static int handle_remove_udev_event(struct device_handler *handler,
		struct event *event)
{
	struct discover_device *dev;

	dev = find_device(handler, event->device);
	if (!dev)
		return 0;

	/* remove device from handler device array */
	device_handler_remove(handler, dev);

	return 0;
}

static int handle_add_user_event(struct device_handler *handler,
		struct event *event)
{
	struct discover_context *ctx;
	struct discover_device *dev;
	int rc;

	assert(event->device);

	ctx = talloc(handler, struct discover_context);
	ctx->event = event;
	list_init(&ctx->boot_options);

	dev = discover_device_create(handler, ctx, event);
	ctx->device = dev;

	rc = parse_user_event(ctx, event);

	if (!rc)
		context_commit(handler, ctx);

	return rc;
}

static int handle_remove_user_event(struct device_handler *handler,
		struct event *event)
{
	struct discover_device *dev = find_device(handler, event->device);

	if (!dev)
		return 0;

	/* remove device from handler device array */
	device_handler_remove(handler, dev);

	return 0;
}

static enum conf_method parse_conf_method(const char *str)
{

	if (!strcasecmp(str, "dhcp")) {
		return CONF_METHOD_DHCP;
	}
	return CONF_METHOD_UNKNOWN;
}

static int handle_conf_user_event(struct device_handler *handler,
		struct event *event)
{
	struct discover_context *ctx;
	struct discover_device *dev;
	enum conf_method method;
	const char *val;

	ctx = talloc(handler, struct discover_context);
	ctx->event = event;
	list_init(&ctx->boot_options);

	val = event_get_param(event, "url");
	if (!val) {
		talloc_free(ctx);
		return 0;
	}

	ctx->conf_url = pb_url_parse(ctx, val);
	if (!ctx->conf_url) {
		talloc_free(ctx);
		return 0;
	}

	val = event_get_param(event, "method");
	if (!val) {
		talloc_free(ctx);
		return 0;
	}

	method = parse_conf_method(val);
	if (method == CONF_METHOD_UNKNOWN) {
		talloc_free(ctx);
		return 0;
	}

	dev = discover_device_create(handler, ctx, event);
	ctx->device = dev;

	iterate_parsers(ctx, method);

	context_commit(handler, ctx);

	return 0;
}

typedef int (*event_handler)(struct device_handler *, struct event *);

static event_handler handlers[EVENT_TYPE_MAX][EVENT_ACTION_MAX] = {
	[EVENT_TYPE_UDEV] = {
		[EVENT_ACTION_ADD]	= handle_add_udev_event,
		[EVENT_ACTION_REMOVE]	= handle_remove_udev_event,
	},
	[EVENT_TYPE_USER] = {
		[EVENT_ACTION_ADD]	= handle_add_user_event,
		[EVENT_ACTION_REMOVE]	= handle_remove_user_event,
		[EVENT_ACTION_CONF]	= handle_conf_user_event,
	}
};

int device_handler_event(struct device_handler *handler,
		struct event *event)
{
	if (event->type >= EVENT_TYPE_MAX ||
			event->action >= EVENT_ACTION_MAX ||
			!handlers[event->type][event->action]) {
		pb_log("%s unknown type/action: %d/%d\n", __func__,
				event->type, event->action);
		return 0;
	}

	return handlers[event->type][event->action](handler, event);
}

struct device_handler *device_handler_init(struct discover_server *server,
		int dry_run)
{
	struct device_handler *handler;

	handler = talloc(NULL, struct device_handler);
	handler->devices = NULL;
	handler->n_devices = 0;
	handler->server = server;
	handler->dry_run = dry_run;
	list_init(&handler->unresolved_boot_options);

	/* set up our mount point base */
	pb_mkdir_recursive(mount_base());

	parser_init();

	return handler;
}

void device_handler_destroy(struct device_handler *handler)
{
	talloc_free(handler);
}

static int device_match_path(struct discover_device *dev, const char *path)
{
	return dev->device_path && !strcmp(dev->device_path, path);
}

static int device_match_uuid(struct discover_device *dev, const char *uuid)
{
	return dev->uuid && !strcmp(dev->uuid, uuid);
}

static int device_match_label(struct discover_device *dev, const char *label)
{
	return dev->label && !strcmp(dev->label, label);
}

static int device_match_id(struct discover_device *dev, const char *id)
{
	return !strcmp(dev->device->id, id);
}

static struct discover_device *device_lookup(
		struct device_handler *device_handler,
		int (match_fn)(struct discover_device *, const char *),
		const char *str)
{
	struct discover_device *dev;
	unsigned int i;

	if (!str)
		return NULL;

	for (i = 0; i < device_handler->n_devices; i++) {
		dev = device_handler->devices[i];

		if (match_fn(dev, str))
			return dev;
	}

	return NULL;
}

struct discover_device *device_lookup_by_name(struct device_handler *handler,
		const char *name)
{
	struct discover_device *dev;
	char *path;

	if (strncmp(name, "/dev/", strlen("/dev/")))
		path = talloc_asprintf(NULL, "/dev/%s", name);
	else
		path = talloc_strdup(NULL, name);

	dev = device_lookup_by_path(handler, path);

	talloc_free(path);

	return dev;
}

struct discover_device *device_lookup_by_path(
		struct device_handler *device_handler,
		const char *path)
{
	return device_lookup(device_handler, device_match_path, path);
}

struct discover_device *device_lookup_by_uuid(
		struct device_handler *device_handler,
		const char *uuid)
{
	return device_lookup(device_handler, device_match_uuid, uuid);
}

struct discover_device *device_lookup_by_label(
		struct device_handler *device_handler,
		const char *label)
{
	return device_lookup(device_handler, device_match_label, label);
}

struct discover_device *device_lookup_by_id(
		struct device_handler *device_handler,
		const char *id)
{
	return device_lookup(device_handler, device_match_id, id);
}

static struct discover_boot_option *find_boot_option_by_id(
		struct device_handler *handler, const char *id)
{
	unsigned int i;

	for (i = 0; i < handler->n_devices; i++) {
		struct discover_device *dev = handler->devices[i];
		struct discover_boot_option *opt;

		list_for_each_entry(&dev->boot_options, opt, list)
			if (!strcmp(opt->option->id, id))
				return opt;
	}

	return NULL;
}

static void boot_status(void *arg, struct boot_status *status)
{
	struct device_handler *handler = arg;

	discover_server_notify_boot_status(handler->server, status);
}

void device_handler_boot(struct device_handler *handler,
		struct boot_command *cmd)
{
	struct discover_boot_option *opt;

	opt = find_boot_option_by_id(handler, cmd->option_id);

	boot(handler, opt, cmd, handler->dry_run, boot_status, handler);
}
OpenPOWER on IntegriCloud