xref: /netbsd-src/external/gpl2/lvm2/dist/libdm/ioctl/libdm-iface.c (revision 017d3467b169e862a7194e0556d75844a27c1282)
1 /*	$NetBSD: libdm-iface.c,v 1.3 2010/12/26 14:48:34 christos Exp $	*/
2 
3 /*
4  * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
5  * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
6  *
7  * This file is part of the device-mapper userspace tools.
8  *
9  * This copyrighted material is made available to anyone wishing to use,
10  * modify, copy, or redistribute it subject to the terms and conditions
11  * of the GNU Lesser General Public License v.2.1.
12  *
13  * You should have received a copy of the GNU Lesser General Public License
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
16  */
17 
18 #include "dmlib.h"
19 #include "libdm-targets.h"
20 #include "libdm-common.h"
21 
22 #ifdef DM_COMPAT
23 #  include "libdm-compat.h"
24 #endif
25 
26 #include <fcntl.h>
27 #include <dirent.h>
28 #include <sys/ioctl.h>
29 #include <sys/utsname.h>
30 #include <limits.h>
31 
32 #ifdef linux
33 #  include "kdev_t.h"
34 #  include <linux/limits.h>
35 #else
36 #  define MAJOR(x) major((x))
37 #  define MINOR(x) minor((x))
38 #  define MKDEV(x,y) makedev((x),(y))
39 #endif
40 
41 #include "dm-ioctl.h"
42 
43 /*
44  * Ensure build compatibility.
45  * The hard-coded versions here are the highest present
46  * in the _cmd_data arrays.
47  */
48 
49 #if !((DM_VERSION_MAJOR == 1 && DM_VERSION_MINOR >= 0) || \
50       (DM_VERSION_MAJOR == 4 && DM_VERSION_MINOR >= 0))
51 #error The version of dm-ioctl.h included is incompatible.
52 #endif
53 
54 /* FIXME This should be exported in device-mapper.h */
55 #define DM_NAME "device-mapper"
56 
57 #define PROC_MISC "/proc/misc"
58 #define PROC_DEVICES "/proc/devices"
59 #define MISC_NAME "misc"
60 
61 #define NUMBER_OF_MAJORS 4096
62 
63 /* dm major version no for running kernel */
64 static unsigned _dm_version = DM_VERSION_MAJOR;
65 static unsigned _dm_version_minor = 0;
66 static unsigned _dm_version_patchlevel = 0;
67 static int _log_suppress = 0;
68 
69 /*
70  * If the kernel dm driver only supports one major number
71  * we store it in _dm_device_major.  Otherwise we indicate
72  * which major numbers have been claimed by device-mapper
73  * in _dm_bitset.
74  */
75 static unsigned _dm_multiple_major_support = 1;
76 static dm_bitset_t _dm_bitset = NULL;
77 static uint32_t _dm_device_major = 0;
78 
79 static int _control_fd = -1;
80 static int _version_checked = 0;
81 static int _version_ok = 1;
82 static unsigned _ioctl_buffer_double_factor = 0;
83 
84 
85 /*
86  * Support both old and new major numbers to ease the transition.
87  * Clumsy, but only temporary.
88  */
89 #if DM_VERSION_MAJOR == 4 && defined(DM_COMPAT)
90 const int _dm_compat = 1;
91 #else
92 const int _dm_compat = 0;
93 #endif
94 
95 
96 /* *INDENT-OFF* */
97 static struct cmd_data _cmd_data_v4[] = {
98 	{"create",	DM_DEV_CREATE,		{4, 0, 0}},
99 	{"reload",	DM_TABLE_LOAD,		{4, 0, 0}},
100 	{"remove",	DM_DEV_REMOVE,		{4, 0, 0}},
101 	{"remove_all",	DM_REMOVE_ALL,		{4, 0, 0}},
102 	{"suspend",	DM_DEV_SUSPEND,		{4, 0, 0}},
103 	{"resume",	DM_DEV_SUSPEND,		{4, 0, 0}},
104 	{"info",	DM_DEV_STATUS,		{4, 0, 0}},
105 	{"deps",	DM_TABLE_DEPS,		{4, 0, 0}},
106 	{"rename",	DM_DEV_RENAME,		{4, 0, 0}},
107 	{"version",	DM_VERSION,		{4, 0, 0}},
108 	{"status",	DM_TABLE_STATUS,	{4, 0, 0}},
109 	{"table",	DM_TABLE_STATUS,	{4, 0, 0}},
110 	{"waitevent",	DM_DEV_WAIT,		{4, 0, 0}},
111 	{"names",	DM_LIST_DEVICES,	{4, 0, 0}},
112 	{"clear",	DM_TABLE_CLEAR,		{4, 0, 0}},
113 	{"mknodes",	DM_DEV_STATUS,		{4, 0, 0}},
114 #ifdef DM_LIST_VERSIONS
115 	{"versions",	DM_LIST_VERSIONS,	{4, 1, 0}},
116 #endif
117 #ifdef DM_TARGET_MSG
118 	{"message",	DM_TARGET_MSG,		{4, 2, 0}},
119 #endif
120 #ifdef DM_DEV_SET_GEOMETRY
121 	{"setgeometry",	DM_DEV_SET_GEOMETRY,	{4, 6, 0}},
122 #endif
123 };
124 /* *INDENT-ON* */
125 
126 #define ALIGNMENT_V1 sizeof(int)
127 #define ALIGNMENT 8
128 
129 /* FIXME Rejig library to record & use errno instead */
130 #ifndef DM_EXISTS_FLAG
131 #  define DM_EXISTS_FLAG 0x00000004
132 #endif
133 
_align(void * ptr,unsigned int a)134 static void *_align(void *ptr, unsigned int a)
135 {
136 	register unsigned long agn = --a;
137 
138 	return (void *) (((unsigned long) ptr + agn) & ~agn);
139 }
140 
141 #ifdef DM_IOCTLS
142 /*
143  * Set number to NULL to populate _dm_bitset - otherwise first
144  * match is returned.
145  */
_get_proc_number(const char * file,const char * name,uint32_t * number)146 static int _get_proc_number(const char *file, const char *name,
147 			    uint32_t *number)
148 {
149 	FILE *fl;
150 	char nm[256];
151 	int c;
152 	uint32_t num;
153 
154 	if (!(fl = fopen(file, "r"))) {
155 		log_sys_error("fopen", file);
156 		return 0;
157 	}
158 
159 	while (!feof(fl)) {
160 		if (fscanf(fl, "%d %255s\n", &num, &nm[0]) == 2) {
161 			if (!strcmp(name, nm)) {
162 				if (number) {
163 					*number = num;
164 					if (fclose(fl))
165 						log_sys_error("fclose", file);
166 					return 1;
167 				}
168 				dm_bit_set(_dm_bitset, num);
169 			}
170 		} else do {
171 			c = fgetc(fl);
172 		} while (c != EOF && c != '\n');
173 	}
174 	if (fclose(fl))
175 		log_sys_error("fclose", file);
176 
177 	if (number) {
178 		log_error("%s: No entry for %s found", file, name);
179 		return 0;
180 	}
181 
182 	return 1;
183 }
184 
_control_device_number(uint32_t * major,uint32_t * minor)185 static int _control_device_number(uint32_t *major, uint32_t *minor)
186 {
187 	if (!_get_proc_number(PROC_DEVICES, MISC_NAME, major) ||
188 	    !_get_proc_number(PROC_MISC, DM_NAME, minor)) {
189 		*major = 0;
190 		return 0;
191 	}
192 
193 	return 1;
194 }
195 
196 /*
197  * Returns 1 if exists; 0 if it doesn't; -1 if it's wrong
198  */
_control_exists(const char * control,uint32_t major,uint32_t minor)199 static int _control_exists(const char *control, uint32_t major, uint32_t minor)
200 {
201 	struct stat buf;
202 
203 	if (stat(control, &buf) < 0) {
204 		if (errno != ENOENT)
205 			log_sys_error("stat", control);
206 		return 0;
207 	}
208 
209 	if (!S_ISCHR(buf.st_mode)) {
210 		log_verbose("%s: Wrong inode type", control);
211 		if (!unlink(control))
212 			return 0;
213 		log_sys_error("unlink", control);
214 		return -1;
215 	}
216 
217 	if (major && buf.st_rdev != MKDEV(major, minor)) {
218 		log_verbose("%s: Wrong device number: (%u, %u) instead of "
219 			    "(%u, %u)", control,
220 			    MAJOR(buf.st_mode), MINOR(buf.st_mode),
221 			    major, minor);
222 		if (!unlink(control))
223 			return 0;
224 		log_sys_error("unlink", control);
225 		return -1;
226 	}
227 
228 	return 1;
229 }
230 
_create_control(const char * control,uint32_t major,uint32_t minor)231 static int _create_control(const char *control, uint32_t major, uint32_t minor)
232 {
233 	int ret;
234 	mode_t old_umask;
235 
236 	if (!major)
237 		return 0;
238 
239 	old_umask = umask(DM_DEV_DIR_UMASK);
240 	ret = dm_create_dir(dm_dir());
241 	umask(old_umask);
242 
243 	if (!ret)
244 		return 0;
245 
246 	log_verbose("Creating device %s (%u, %u)", control, major, minor);
247 
248 	old_umask = umask(0);
249 	if (mknod(control, S_IFCHR | DM_DEVICE_MODE,
250 		  MKDEV(major, minor)) < 0)  {
251 		umask(old_umask);
252 		log_sys_error("mknod", control);
253 		return 0;
254 	}
255 	umask(old_umask);
256 	if (chown(control, DM_DEVICE_UID, DM_DEVICE_GID) == -1) {
257 		log_sys_error("cbown", control);
258 		return 0;
259 	}
260 
261 #ifdef HAVE_SELINUX
262 	if (!dm_set_selinux_context(control, S_IFCHR)) {
263 		stack;
264 		return 0;
265 	}
266 #endif
267 
268 	return 1;
269 }
270 #endif
271 
272 /*
273  * FIXME Update bitset in long-running process if dm claims new major numbers.
274  */
_create_dm_bitset(void)275 static int _create_dm_bitset(void)
276 {
277 #ifdef DM_IOCTLS
278 	struct utsname uts;
279 
280 	if (_dm_bitset || _dm_device_major)
281 		return 1;
282 
283 	if (uname(&uts))
284 		return 0;
285 
286 	/*
287 	 * 2.6 kernels are limited to one major number.
288 	 * Assume 2.4 kernels are patched not to.
289 	 * FIXME Check _dm_version and _dm_version_minor if 2.6 changes this.
290 	 */
291 	if (!strncmp(uts.release, "2.6.", 4))
292 		_dm_multiple_major_support = 0;
293 
294 	if (!_dm_multiple_major_support) {
295 		if (!_get_proc_number(PROC_DEVICES, DM_NAME, &_dm_device_major))
296 			return 0;
297 		return 1;
298 	}
299 
300 	/* Multiple major numbers supported */
301 	if (!(_dm_bitset = dm_bitset_create(NULL, NUMBER_OF_MAJORS)))
302 		return 0;
303 
304 	if (!_get_proc_number(PROC_DEVICES, DM_NAME, NULL)) {
305 		dm_bitset_destroy(_dm_bitset);
306 		_dm_bitset = NULL;
307 		return 0;
308 	}
309 
310 	return 1;
311 #else
312 	return 0;
313 #endif
314 }
315 
dm_is_dm_major(uint32_t major)316 int dm_is_dm_major(uint32_t major)
317 {
318 	if (!_create_dm_bitset())
319 		return 0;
320 
321 	if (_dm_multiple_major_support)
322 		return dm_bit(_dm_bitset, major) ? 1 : 0;
323 	else
324 		return (major == _dm_device_major) ? 1 : 0;
325 }
326 
_open_control(void)327 static int _open_control(void)
328 {
329 #ifdef DM_IOCTLS
330 	char control[PATH_MAX];
331 	uint32_t major = 0, minor;
332 
333 	if (_control_fd != -1)
334 		return 1;
335 
336 	snprintf(control, sizeof(control), "%s/control", dm_dir());
337 
338 	if (!_control_device_number(&major, &minor))
339 		log_error("Is device-mapper driver missing from kernel?");
340 
341 	if (!_control_exists(control, major, minor) &&
342 	    !_create_control(control, major, minor))
343 		goto error;
344 
345 	if ((_control_fd = open(control, O_RDWR)) < 0) {
346 		log_sys_error("open", control);
347 		goto error;
348 	}
349 
350 	if (!_create_dm_bitset()) {
351 		log_error("Failed to set up list of device-mapper major numbers");
352 		return 0;
353 	}
354 
355 	return 1;
356 
357 error:
358 	log_error("Failure to communicate with kernel device-mapper driver.");
359 	return 0;
360 #else
361 	return 1;
362 #endif
363 }
364 
dm_task_destroy(struct dm_task * dmt)365 void dm_task_destroy(struct dm_task *dmt)
366 {
367 	struct target *t, *n;
368 
369 	for (t = dmt->head; t; t = n) {
370 		n = t->next;
371 		dm_free(t->params);
372 		dm_free(t->type);
373 		dm_free(t);
374 	}
375 
376 	if (dmt->dev_name)
377 		dm_free(dmt->dev_name);
378 
379 	if (dmt->newname)
380 		dm_free(dmt->newname);
381 
382 	if (dmt->message)
383 		dm_free(dmt->message);
384 
385 	if (dmt->dmi.v4)
386 		dm_free(dmt->dmi.v4);
387 
388 	if (dmt->uuid)
389 		dm_free(dmt->uuid);
390 
391 	dm_free(dmt);
392 }
393 
394 /*
395  * Protocol Version 1 compatibility functions.
396  */
397 
398 #ifdef DM_COMPAT
399 
_dm_task_get_driver_version_v1(struct dm_task * dmt,char * version,size_t size)400 static int _dm_task_get_driver_version_v1(struct dm_task *dmt, char *version,
401 					  size_t size)
402 {
403 	unsigned int *v;
404 
405 	if (!dmt->dmi.v1) {
406 		version[0] = '\0';
407 		return 0;
408 	}
409 
410 	v = dmt->dmi.v1->version;
411 	snprintf(version, size, "%u.%u.%u", v[0], v[1], v[2]);
412 	return 1;
413 }
414 
415 /* Unmarshall the target info returned from a status call */
_unmarshal_status_v1(struct dm_task * dmt,struct dm_ioctl_v1 * dmi)416 static int _unmarshal_status_v1(struct dm_task *dmt, struct dm_ioctl_v1 *dmi)
417 {
418 	char *outbuf = (char *) dmi + dmi->data_start;
419 	char *outptr = outbuf;
420 	int32_t i;
421 	struct dm_target_spec_v1 *spec;
422 
423 	for (i = 0; i < dmi->target_count; i++) {
424 		spec = (struct dm_target_spec_v1 *) outptr;
425 
426 		if (!dm_task_add_target(dmt, spec->sector_start,
427 					(uint64_t) spec->length,
428 					spec->target_type,
429 					outptr + sizeof(*spec))) {
430 			return 0;
431 		}
432 
433 		outptr = outbuf + spec->next;
434 	}
435 
436 	return 1;
437 }
438 
_dm_format_dev_v1(char * buf,int bufsize,uint32_t dev_major,uint32_t dev_minor)439 static int _dm_format_dev_v1(char *buf, int bufsize, uint32_t dev_major,
440 			     uint32_t dev_minor)
441 {
442 	int r;
443 
444 	if (bufsize < 8)
445 		return 0;
446 
447 	r = snprintf(buf, bufsize, "%03x:%03x", dev_major, dev_minor);
448 	if (r < 0 || r > bufsize - 1)
449 		return 0;
450 
451 	return 1;
452 }
453 
_dm_task_get_info_v1(struct dm_task * dmt,struct dm_info * info)454 static int _dm_task_get_info_v1(struct dm_task *dmt, struct dm_info *info)
455 {
456 	if (!dmt->dmi.v1)
457 		return 0;
458 
459 	memset(info, 0, sizeof(*info));
460 
461 	info->exists = dmt->dmi.v1->flags & DM_EXISTS_FLAG ? 1 : 0;
462 	if (!info->exists)
463 		return 1;
464 
465 	info->suspended = dmt->dmi.v1->flags & DM_SUSPEND_FLAG ? 1 : 0;
466 	info->read_only = dmt->dmi.v1->flags & DM_READONLY_FLAG ? 1 : 0;
467 	info->target_count = dmt->dmi.v1->target_count;
468 	info->open_count = dmt->dmi.v1->open_count;
469 	info->event_nr = 0;
470 	info->major = MAJOR(dmt->dmi.v1->dev);
471 	info->minor = MINOR(dmt->dmi.v1->dev);
472 	info->live_table = 1;
473 	info->inactive_table = 0;
474 
475 	return 1;
476 }
477 
_dm_task_get_name_v1(const struct dm_task * dmt)478 static const char *_dm_task_get_name_v1(const struct dm_task *dmt)
479 {
480 	return (dmt->dmi.v1->name);
481 }
482 
_dm_task_get_uuid_v1(const struct dm_task * dmt)483 static const char *_dm_task_get_uuid_v1(const struct dm_task *dmt)
484 {
485 	return (dmt->dmi.v1->uuid);
486 }
487 
_dm_task_get_deps_v1(struct dm_task * dmt)488 static struct dm_deps *_dm_task_get_deps_v1(struct dm_task *dmt)
489 {
490 	log_error("deps version 1 no longer supported by libdevmapper");
491 	return NULL;
492 }
493 
_dm_task_get_names_v1(struct dm_task * dmt)494 static struct dm_names *_dm_task_get_names_v1(struct dm_task *dmt)
495 {
496 	return (struct dm_names *) (((void *) dmt->dmi.v1) +
497 				    dmt->dmi.v1->data_start);
498 }
499 
_add_target_v1(struct target * t,void * out,void * end)500 static void *_add_target_v1(struct target *t, void *out, void *end)
501 {
502 	void *out_sp = out;
503 	struct dm_target_spec_v1 sp;
504 	size_t sp_size = sizeof(struct dm_target_spec_v1);
505 	int len;
506 	const char no_space[] = "Ran out of memory building ioctl parameter";
507 
508 	out += sp_size;
509 	if (out >= end) {
510 		log_error(no_space);
511 		return NULL;
512 	}
513 
514 	sp.status = 0;
515 	sp.sector_start = t->start;
516 	sp.length = t->length;
517 	strncpy(sp.target_type, t->type, sizeof(sp.target_type));
518 
519 	len = strlen(t->params);
520 
521 	if ((out + len + 1) >= end) {
522 		log_error(no_space);
523 
524 		log_error("t->params= '%s'", t->params);
525 		return NULL;
526 	}
527 	strcpy((char *) out, t->params);
528 	out += len + 1;
529 
530 	/* align next block */
531 	out = _align(out, ALIGNMENT_V1);
532 
533 	sp.next = out - out_sp;
534 
535 	memcpy(out_sp, &sp, sp_size);
536 
537 	return out;
538 }
539 
_flatten_v1(struct dm_task * dmt)540 static struct dm_ioctl_v1 *_flatten_v1(struct dm_task *dmt)
541 {
542 	const size_t min_size = 16 * 1024;
543 	const int (*version)[3];
544 
545 	struct dm_ioctl_v1 *dmi;
546 	struct target *t;
547 	size_t len = sizeof(struct dm_ioctl_v1);
548 	void *b, *e;
549 	int count = 0;
550 
551 	for (t = dmt->head; t; t = t->next) {
552 		len += sizeof(struct dm_target_spec_v1);
553 		len += strlen(t->params) + 1 + ALIGNMENT_V1;
554 		count++;
555 	}
556 
557 	if (count && dmt->newname) {
558 		log_error("targets and newname are incompatible");
559 		return NULL;
560 	}
561 
562 	if (dmt->newname)
563 		len += strlen(dmt->newname) + 1;
564 
565 	/*
566 	 * Give len a minimum size so that we have space to store
567 	 * dependencies or status information.
568 	 */
569 	if (len < min_size)
570 		len = min_size;
571 
572 	if (!(dmi = dm_malloc(len)))
573 		return NULL;
574 
575 	memset(dmi, 0, len);
576 
577 	version = &_cmd_data_v1[dmt->type].version;
578 
579 	dmi->version[0] = (*version)[0];
580 	dmi->version[1] = (*version)[1];
581 	dmi->version[2] = (*version)[2];
582 
583 	dmi->data_size = len;
584 	dmi->data_start = sizeof(struct dm_ioctl_v1);
585 
586 	if (dmt->dev_name)
587 		strncpy(dmi->name, dmt->dev_name, sizeof(dmi->name));
588 
589 	if (dmt->type == DM_DEVICE_SUSPEND)
590 		dmi->flags |= DM_SUSPEND_FLAG;
591 	if (dmt->read_only)
592 		dmi->flags |= DM_READONLY_FLAG;
593 
594 	if (dmt->minor >= 0) {
595 		if (dmt->major <= 0) {
596 			log_error("Missing major number for persistent device");
597 			return NULL;
598 		}
599 		dmi->flags |= DM_PERSISTENT_DEV_FLAG;
600 		dmi->dev = MKDEV(dmt->major, dmt->minor);
601 	}
602 
603 	if (dmt->uuid)
604 		strncpy(dmi->uuid, dmt->uuid, sizeof(dmi->uuid));
605 
606 	dmi->target_count = count;
607 
608 	b = (void *) (dmi + 1);
609 	e = (void *) ((char *) dmi + len);
610 
611 	for (t = dmt->head; t; t = t->next)
612 		if (!(b = _add_target_v1(t, b, e)))
613 			goto bad;
614 
615 	if (dmt->newname)
616 		strcpy(b, dmt->newname);
617 
618 	return dmi;
619 
620       bad:
621 	dm_free(dmi);
622 	return NULL;
623 }
624 
_dm_names_v1(struct dm_ioctl_v1 * dmi)625 static int _dm_names_v1(struct dm_ioctl_v1 *dmi)
626 {
627 	const char *dev_dir = dm_dir();
628 	int r = 1, len;
629 	const char *name;
630 	struct dirent *dirent;
631 	DIR *d;
632 	struct dm_names *names, *old_names = NULL;
633 	void *end = (void *) dmi + dmi->data_size;
634 	struct stat buf;
635 	char path[PATH_MAX];
636 
637 	log_warn("WARNING: Device list may be incomplete with interface "
638 		  "version 1.");
639 	log_warn("Please upgrade your kernel device-mapper driver.");
640 
641 	if (!(d = opendir(dev_dir))) {
642 		log_sys_error("opendir", dev_dir);
643 		return 0;
644 	}
645 
646 	names = (struct dm_names *) ((void *) dmi + dmi->data_start);
647 
648 	names->dev = 0;		/* Flags no data */
649 
650 	while ((dirent = readdir(d))) {
651 		name = dirent->d_name;
652 
653 		if (name[0] == '.' || !strcmp(name, "control"))
654 			continue;
655 
656 		if (old_names)
657 			old_names->next = (uint32_t) ((void *) names -
658 						      (void *) old_names);
659 		snprintf(path, sizeof(path), "%s/%s", dev_dir, name);
660 		if (stat(path, &buf)) {
661 			log_sys_error("stat", path);
662 			continue;
663 		}
664 		if (!S_ISBLK(buf.st_mode))
665 			continue;
666 		names->dev = (uint64_t) buf.st_rdev;
667 		names->next = 0;
668 		len = strlen(name);
669 		if (((void *) (names + 1) + len + 1) >= end) {
670 			log_error("Insufficient buffer space for device list");
671 			r = 0;
672 			break;
673 		}
674 
675 		strcpy(names->name, name);
676 
677 		old_names = names;
678 		names = _align((void *) ++names + len + 1, ALIGNMENT);
679 	}
680 
681 	if (closedir(d))
682 		log_sys_error("closedir", dev_dir);
683 
684 	return r;
685 }
686 
_dm_task_run_v1(struct dm_task * dmt)687 static int _dm_task_run_v1(struct dm_task *dmt)
688 {
689 	struct dm_ioctl_v1 *dmi;
690 	unsigned int command;
691 
692 	dmi = _flatten_v1(dmt);
693 	if (!dmi) {
694 		log_error("Couldn't create ioctl argument.");
695 		return 0;
696 	}
697 
698 	if (!_open_control())
699 		return 0;
700 
701 	if ((unsigned) dmt->type >=
702 	    (sizeof(_cmd_data_v1) / sizeof(*_cmd_data_v1))) {
703 		log_error("Internal error: unknown device-mapper task %d",
704 			  dmt->type);
705 		goto bad;
706 	}
707 
708 	command = _cmd_data_v1[dmt->type].cmd;
709 
710 	if (dmt->type == DM_DEVICE_TABLE)
711 		dmi->flags |= DM_STATUS_TABLE_FLAG;
712 
713 	log_debug("dm %s %s %s%s%s [%u]", _cmd_data_v1[dmt->type].name,
714 		  dmi->name, dmi->uuid, dmt->newname ? " " : "",
715 		  dmt->newname ? dmt->newname : "",
716 		  dmi->data_size);
717 	if (dmt->type == DM_DEVICE_LIST) {
718 		if (!_dm_names_v1(dmi))
719 			goto bad;
720 	}
721 #ifdef DM_IOCTLS
722 	else if (ioctl(_control_fd, command, dmi) < 0) {
723 		if (_log_suppress)
724 			log_verbose("device-mapper: %s ioctl failed: %s",
725 				    _cmd_data_v1[dmt->type].name,
726 				    strerror(errno));
727 		else
728 			log_error("device-mapper: %s ioctl failed: %s",
729 				  _cmd_data_v1[dmt->type].name,
730 				  strerror(errno));
731 		goto bad;
732 	}
733 #else /* Userspace alternative for testing */
734 #endif
735 
736 	if (dmi->flags & DM_BUFFER_FULL_FLAG)
737 		/* FIXME Increase buffer size and retry operation (if query) */
738 		log_error("WARNING: libdevmapper buffer too small for data");
739 
740 	switch (dmt->type) {
741 	case DM_DEVICE_CREATE:
742 		add_dev_node(dmt->dev_name, MAJOR(dmi->dev), MINOR(dmi->dev),
743 			     dmt->uid, dmt->gid, dmt->mode, 0);
744 		break;
745 
746 	case DM_DEVICE_REMOVE:
747 		rm_dev_node(dmt->dev_name, 0);
748 		break;
749 
750 	case DM_DEVICE_RENAME:
751 		rename_dev_node(dmt->dev_name, dmt->newname, 0);
752 		break;
753 
754 	case DM_DEVICE_MKNODES:
755 		if (dmi->flags & DM_EXISTS_FLAG)
756 			add_dev_node(dmt->dev_name, MAJOR(dmi->dev),
757 				     MINOR(dmi->dev), dmt->uid,
758 				     dmt->gid, dmt->mode, 0);
759 		else
760 			rm_dev_node(dmt->dev_name, 0);
761 		break;
762 
763 	case DM_DEVICE_STATUS:
764 	case DM_DEVICE_TABLE:
765 		if (!_unmarshal_status_v1(dmt, dmi))
766 			goto bad;
767 		break;
768 
769 	case DM_DEVICE_SUSPEND:
770 	case DM_DEVICE_RESUME:
771 		dmt->type = DM_DEVICE_INFO;
772 		if (!dm_task_run(dmt))
773 			goto bad;
774 		dm_free(dmi);	/* We'll use what info returned */
775 		return 1;
776 	}
777 
778 	dmt->dmi.v1 = dmi;
779 	return 1;
780 
781       bad:
782 	dm_free(dmi);
783 	return 0;
784 }
785 
786 #endif
787 
788 /*
789  * Protocol Version 4 functions.
790  */
791 
dm_task_get_driver_version(struct dm_task * dmt,char * version,size_t size)792 int dm_task_get_driver_version(struct dm_task *dmt, char *version, size_t size)
793 {
794 	unsigned *v;
795 
796 #ifdef DM_COMPAT
797 	if (_dm_version == 1)
798 		return _dm_task_get_driver_version_v1(dmt, version, size);
799 #endif
800 
801 	if (!dmt->dmi.v4) {
802 		version[0] = '\0';
803 		return 0;
804 	}
805 
806 	v = dmt->dmi.v4->version;
807 	snprintf(version, size, "%u.%u.%u", v[0], v[1], v[2]);
808 	_dm_version_minor = v[1];
809 	_dm_version_patchlevel = v[2];
810 
811 	return 1;
812 }
813 
_check_version(char * version,size_t size,int log_suppress)814 static int _check_version(char *version, size_t size, int log_suppress)
815 {
816 	struct dm_task *task;
817 	int r;
818 
819 	if (!(task = dm_task_create(DM_DEVICE_VERSION))) {
820 		log_error("Failed to get device-mapper version");
821 		version[0] = '\0';
822 		return 0;
823 	}
824 
825 	if (log_suppress)
826 		_log_suppress = 1;
827 
828 	r = dm_task_run(task);
829 	dm_task_get_driver_version(task, version, size);
830 	dm_task_destroy(task);
831 	_log_suppress = 0;
832 
833 	return r;
834 }
835 
836 /*
837  * Find out device-mapper's major version number the first time
838  * this is called and whether or not we support it.
839  */
dm_check_version(void)840 int dm_check_version(void)
841 {
842 	char libversion[64], dmversion[64];
843 	const char *compat = "";
844 
845 	if (_version_checked)
846 		return _version_ok;
847 
848 	_version_checked = 1;
849 
850 	if (_check_version(dmversion, sizeof(dmversion), _dm_compat))
851 		return 1;
852 
853 	if (!_dm_compat)
854 		goto bad;
855 
856 	log_verbose("device-mapper ioctl protocol version %u failed. "
857 		    "Trying protocol version 1.", _dm_version);
858 	_dm_version = 1;
859 	if (_check_version(dmversion, sizeof(dmversion), 0)) {
860 		log_verbose("Using device-mapper ioctl protocol version 1");
861 		return 1;
862 	}
863 
864 	compat = "(compat)";
865 
866 	dm_get_library_version(libversion, sizeof(libversion));
867 
868 	log_error("Incompatible libdevmapper %s%s and kernel driver %s",
869 		  libversion, compat, dmversion);
870 
871       bad:
872 	_version_ok = 0;
873 	return 0;
874 }
875 
dm_cookie_supported(void)876 int dm_cookie_supported(void)
877 {
878 	return (dm_check_version() &&
879 	        _dm_version >= 4 &&
880 	        _dm_version_minor >= 15);
881 }
882 
dm_get_next_target(struct dm_task * dmt,void * next,uint64_t * start,uint64_t * length,char ** target_type,char ** params)883 void *dm_get_next_target(struct dm_task *dmt, void *next,
884 			 uint64_t *start, uint64_t *length,
885 			 char **target_type, char **params)
886 {
887 	struct target *t = (struct target *) next;
888 
889 	if (!t)
890 		t = dmt->head;
891 
892 	if (!t)
893 		return NULL;
894 
895 	*start = t->start;
896 	*length = t->length;
897 	*target_type = t->type;
898 	*params = t->params;
899 
900 	return t->next;
901 }
902 
903 /* Unmarshall the target info returned from a status call */
_unmarshal_status(struct dm_task * dmt,struct dm_ioctl * dmi)904 static int _unmarshal_status(struct dm_task *dmt, struct dm_ioctl *dmi)
905 {
906 	char *outbuf = (char *) dmi + dmi->data_start;
907 	char *outptr = outbuf;
908 	uint32_t i;
909 	struct dm_target_spec *spec;
910 
911 	for (i = 0; i < dmi->target_count; i++) {
912 		spec = (struct dm_target_spec *) outptr;
913 		if (!dm_task_add_target(dmt, spec->sector_start,
914 					spec->length,
915 					spec->target_type,
916 					outptr + sizeof(*spec))) {
917 			return 0;
918 		}
919 
920 		outptr = outbuf + spec->next;
921 	}
922 
923 	return 1;
924 }
925 
dm_format_dev(char * buf,int bufsize,uint32_t dev_major,uint32_t dev_minor)926 int dm_format_dev(char *buf, int bufsize, uint32_t dev_major,
927 		  uint32_t dev_minor)
928 {
929 	int r;
930 
931 #ifdef DM_COMPAT
932 	if (_dm_version == 1)
933 		return _dm_format_dev_v1(buf, bufsize, dev_major, dev_minor);
934 #endif
935 
936 	if (bufsize < 8)
937 		return 0;
938 
939 	r = snprintf(buf, (size_t) bufsize, "%u:%u", dev_major, dev_minor);
940 	if (r < 0 || r > bufsize - 1)
941 		return 0;
942 
943 	return 1;
944 }
945 
dm_task_get_info(struct dm_task * dmt,struct dm_info * info)946 int dm_task_get_info(struct dm_task *dmt, struct dm_info *info)
947 {
948 #ifdef DM_COMPAT
949 	if (_dm_version == 1)
950 		return _dm_task_get_info_v1(dmt, info);
951 #endif
952 
953 	if (!dmt->dmi.v4)
954 		return 0;
955 
956 	memset(info, 0, sizeof(*info));
957 
958 	info->exists = dmt->dmi.v4->flags & DM_EXISTS_FLAG ? 1 : 0;
959 	if (!info->exists)
960 		return 1;
961 
962 	info->suspended = dmt->dmi.v4->flags & DM_SUSPEND_FLAG ? 1 : 0;
963 	info->read_only = dmt->dmi.v4->flags & DM_READONLY_FLAG ? 1 : 0;
964 	info->live_table = dmt->dmi.v4->flags & DM_ACTIVE_PRESENT_FLAG ? 1 : 0;
965 	info->inactive_table = dmt->dmi.v4->flags & DM_INACTIVE_PRESENT_FLAG ?
966 	    1 : 0;
967 	info->target_count = dmt->dmi.v4->target_count;
968 	info->open_count = dmt->dmi.v4->open_count;
969 	info->event_nr = dmt->dmi.v4->event_nr;
970 	info->major = MAJOR(dmt->dmi.v4->dev);
971 	info->minor = MINOR(dmt->dmi.v4->dev);
972 
973 	return 1;
974 }
975 
dm_task_get_read_ahead(const struct dm_task * dmt,uint32_t * read_ahead)976 uint32_t dm_task_get_read_ahead(const struct dm_task *dmt, uint32_t *read_ahead)
977 {
978 	const char *dev_name;
979 
980 	*read_ahead = 0;
981 
982 #ifdef DM_COMPAT
983 	/* Not supporting this */
984         if (_dm_version == 1)
985                 return 1;
986 #endif
987 
988         if (!dmt->dmi.v4 || !(dmt->dmi.v4->flags & DM_EXISTS_FLAG))
989 		return 0;
990 
991 	if (*dmt->dmi.v4->name)
992 		dev_name = dmt->dmi.v4->name;
993 	else if (dmt->dev_name)
994 		dev_name = dmt->dev_name;
995 	else {
996 		log_error("Get read ahead request failed: device name unrecorded.");
997 		return 0;
998 	}
999 
1000 	return get_dev_node_read_ahead(dev_name, read_ahead);
1001 }
1002 
dm_task_get_name(const struct dm_task * dmt)1003 const char *dm_task_get_name(const struct dm_task *dmt)
1004 {
1005 #ifdef DM_COMPAT
1006 	if (_dm_version == 1)
1007 		return _dm_task_get_name_v1(dmt);
1008 #endif
1009 
1010 	return (dmt->dmi.v4->name);
1011 }
1012 
dm_task_get_uuid(const struct dm_task * dmt)1013 const char *dm_task_get_uuid(const struct dm_task *dmt)
1014 {
1015 #ifdef DM_COMPAT
1016 	if (_dm_version == 1)
1017 		return _dm_task_get_uuid_v1(dmt);
1018 #endif
1019 
1020 	return (dmt->dmi.v4->uuid);
1021 }
1022 
dm_task_get_deps(struct dm_task * dmt)1023 struct dm_deps *dm_task_get_deps(struct dm_task *dmt)
1024 {
1025 #ifdef DM_COMPAT
1026 	if (_dm_version == 1)
1027 		return _dm_task_get_deps_v1(dmt);
1028 #endif
1029 
1030 	return (struct dm_deps *) (((void *) dmt->dmi.v4) +
1031 				   dmt->dmi.v4->data_start);
1032 }
1033 
dm_task_get_names(struct dm_task * dmt)1034 struct dm_names *dm_task_get_names(struct dm_task *dmt)
1035 {
1036 #ifdef DM_COMPAT
1037 	if (_dm_version == 1)
1038 		return _dm_task_get_names_v1(dmt);
1039 #endif
1040 
1041 	return (struct dm_names *) (((void *) dmt->dmi.v4) +
1042 				    dmt->dmi.v4->data_start);
1043 }
1044 
dm_task_get_versions(struct dm_task * dmt)1045 struct dm_versions *dm_task_get_versions(struct dm_task *dmt)
1046 {
1047 	return (struct dm_versions *) (((void *) dmt->dmi.v4) +
1048 				       dmt->dmi.v4->data_start);
1049 }
1050 
dm_task_set_ro(struct dm_task * dmt)1051 int dm_task_set_ro(struct dm_task *dmt)
1052 {
1053 	dmt->read_only = 1;
1054 	return 1;
1055 }
1056 
dm_task_set_read_ahead(struct dm_task * dmt,uint32_t read_ahead,uint32_t read_ahead_flags)1057 int dm_task_set_read_ahead(struct dm_task *dmt, uint32_t read_ahead,
1058 			   uint32_t read_ahead_flags)
1059 {
1060 	dmt->read_ahead = read_ahead;
1061 	dmt->read_ahead_flags = read_ahead_flags;
1062 
1063 	return 1;
1064 }
1065 
dm_task_suppress_identical_reload(struct dm_task * dmt)1066 int dm_task_suppress_identical_reload(struct dm_task *dmt)
1067 {
1068 	dmt->suppress_identical_reload = 1;
1069 	return 1;
1070 }
1071 
dm_task_set_newname(struct dm_task * dmt,const char * newname)1072 int dm_task_set_newname(struct dm_task *dmt, const char *newname)
1073 {
1074 	if (strchr(newname, '/')) {
1075 		log_error("Name \"%s\" invalid. It contains \"/\".", newname);
1076 		return 0;
1077 	}
1078 
1079 	if (strlen(newname) >= DM_NAME_LEN) {
1080 		log_error("Name \"%s\" too long", newname);
1081 		return 0;
1082 	}
1083 
1084 	if (!(dmt->newname = dm_strdup(newname))) {
1085 		log_error("dm_task_set_newname: strdup(%s) failed", newname);
1086 		return 0;
1087 	}
1088 
1089 	return 1;
1090 }
1091 
dm_task_set_message(struct dm_task * dmt,const char * message)1092 int dm_task_set_message(struct dm_task *dmt, const char *message)
1093 {
1094 	if (!(dmt->message = dm_strdup(message))) {
1095 		log_error("dm_task_set_message: strdup(%s) failed", message);
1096 		return 0;
1097 	}
1098 
1099 	return 1;
1100 }
1101 
dm_task_set_sector(struct dm_task * dmt,uint64_t sector)1102 int dm_task_set_sector(struct dm_task *dmt, uint64_t sector)
1103 {
1104 	dmt->sector = sector;
1105 
1106 	return 1;
1107 }
1108 
dm_task_set_geometry(struct dm_task * dmt,const char * cylinders,const char * heads,const char * sectors,const char * start)1109 int dm_task_set_geometry(struct dm_task *dmt, const char *cylinders, const char *heads, const char *sectors, const char *start)
1110 {
1111 	size_t len = strlen(cylinders) + 1 + strlen(heads) + 1 + strlen(sectors) + 1 + strlen(start) + 1;
1112 
1113 	if (!(dmt->geometry = dm_malloc(len))) {
1114 		log_error("dm_task_set_geometry: dm_malloc failed");
1115 		return 0;
1116 	}
1117 
1118 	if (sprintf(dmt->geometry, "%s %s %s %s", cylinders, heads, sectors, start) < 0) {
1119 		log_error("dm_task_set_geometry: sprintf failed");
1120 		return 0;
1121 	}
1122 
1123 	return 1;
1124 }
1125 
dm_task_no_flush(struct dm_task * dmt)1126 int dm_task_no_flush(struct dm_task *dmt)
1127 {
1128 	dmt->no_flush = 1;
1129 
1130 	return 1;
1131 }
1132 
dm_task_no_open_count(struct dm_task * dmt)1133 int dm_task_no_open_count(struct dm_task *dmt)
1134 {
1135 	dmt->no_open_count = 1;
1136 
1137 	return 1;
1138 }
1139 
dm_task_skip_lockfs(struct dm_task * dmt)1140 int dm_task_skip_lockfs(struct dm_task *dmt)
1141 {
1142 	dmt->skip_lockfs = 1;
1143 
1144 	return 1;
1145 }
1146 
dm_task_query_inactive_table(struct dm_task * dmt)1147 int dm_task_query_inactive_table(struct dm_task *dmt)
1148 {
1149 	dmt->query_inactive_table = 1;
1150 
1151 	return 1;
1152 }
1153 
dm_task_set_event_nr(struct dm_task * dmt,uint32_t event_nr)1154 int dm_task_set_event_nr(struct dm_task *dmt, uint32_t event_nr)
1155 {
1156 	dmt->event_nr = event_nr;
1157 
1158 	return 1;
1159 }
1160 
create_target(uint64_t start,uint64_t len,const char * type,const char * params)1161 struct target *create_target(uint64_t start, uint64_t len, const char *type,
1162 			     const char *params)
1163 {
1164 	struct target *t = dm_malloc(sizeof(*t));
1165 
1166 	if (!t) {
1167 		log_error("create_target: malloc(%" PRIsize_t ") failed",
1168 			  sizeof(*t));
1169 		return NULL;
1170 	}
1171 
1172 	memset(t, 0, sizeof(*t));
1173 
1174 	if (!(t->params = dm_strdup(params))) {
1175 		log_error("create_target: strdup(params) failed");
1176 		goto bad;
1177 	}
1178 
1179 	if (!(t->type = dm_strdup(type))) {
1180 		log_error("create_target: strdup(type) failed");
1181 		goto bad;
1182 	}
1183 
1184 	t->start = start;
1185 	t->length = len;
1186 	return t;
1187 
1188       bad:
1189 	dm_free(t->params);
1190 	dm_free(t->type);
1191 	dm_free(t);
1192 	return NULL;
1193 }
1194 
_add_target(struct target * t,void * out,void * end)1195 static void *_add_target(struct target *t, void *out, void *end)
1196 {
1197 	void *out_sp = out;
1198 	struct dm_target_spec sp;
1199 	size_t sp_size = sizeof(struct dm_target_spec);
1200 	int len;
1201 	const char no_space[] = "Ran out of memory building ioctl parameter";
1202 
1203 	out += sp_size;
1204 	if (out >= end) {
1205 		log_error(no_space);
1206 		return NULL;
1207 	}
1208 
1209 	sp.status = 0;
1210 	sp.sector_start = t->start;
1211 	sp.length = t->length;
1212 	strncpy(sp.target_type, t->type, sizeof(sp.target_type));
1213 
1214 	len = strlen(t->params);
1215 
1216 	if ((out + len + 1) >= end) {
1217 		log_error(no_space);
1218 
1219 		log_error("t->params= '%s'", t->params);
1220 		return NULL;
1221 	}
1222 	strcpy((char *) out, t->params);
1223 	out += len + 1;
1224 
1225 	/* align next block */
1226 	out = _align(out, ALIGNMENT);
1227 
1228 	sp.next = out - out_sp;
1229 	memcpy(out_sp, &sp, sp_size);
1230 
1231 	return out;
1232 }
1233 
_lookup_dev_name(uint64_t dev,char * buf,size_t len)1234 static int _lookup_dev_name(uint64_t dev, char *buf, size_t len)
1235 {
1236 	struct dm_names *names;
1237 	unsigned next = 0;
1238 	struct dm_task *dmt;
1239 	int r = 0;
1240 
1241 	if (!(dmt = dm_task_create(DM_DEVICE_LIST)))
1242 		return 0;
1243 
1244 	if (!dm_task_run(dmt))
1245 		goto out;
1246 
1247 	if (!(names = dm_task_get_names(dmt)))
1248 		goto out;
1249 
1250 	if (!names->dev)
1251 		goto out;
1252 
1253 	do {
1254 		names = (void *) names + next;
1255 		if (names->dev == dev) {
1256 			strncpy(buf, names->name, len);
1257 			r = 1;
1258 			break;
1259 		}
1260 		next = names->next;
1261 	} while (next);
1262 
1263       out:
1264 	dm_task_destroy(dmt);
1265 	return r;
1266 }
1267 
_flatten(struct dm_task * dmt,unsigned repeat_count)1268 static struct dm_ioctl *_flatten(struct dm_task *dmt, unsigned repeat_count)
1269 {
1270 	const size_t min_size = 16 * 1024;
1271 	const int (*version)[3];
1272 
1273 	struct dm_ioctl *dmi;
1274 	struct target *t;
1275 	struct dm_target_msg *tmsg;
1276 	size_t len = sizeof(struct dm_ioctl);
1277 	void *b, *e;
1278 	int count = 0;
1279 
1280 	for (t = dmt->head; t; t = t->next) {
1281 		len += sizeof(struct dm_target_spec);
1282 		len += strlen(t->params) + 1 + ALIGNMENT;
1283 		count++;
1284 	}
1285 
1286 	if (count && (dmt->sector || dmt->message)) {
1287 		log_error("targets and message are incompatible");
1288 		return NULL;
1289 	}
1290 
1291 	if (count && dmt->newname) {
1292 		log_error("targets and newname are incompatible");
1293 		return NULL;
1294 	}
1295 
1296 	if (count && dmt->geometry) {
1297 		log_error("targets and geometry are incompatible");
1298 		return NULL;
1299 	}
1300 
1301 	if (dmt->newname && (dmt->sector || dmt->message)) {
1302 		log_error("message and newname are incompatible");
1303 		return NULL;
1304 	}
1305 
1306 	if (dmt->newname && dmt->geometry) {
1307 		log_error("geometry and newname are incompatible");
1308 		return NULL;
1309 	}
1310 
1311 	if (dmt->geometry && (dmt->sector || dmt->message)) {
1312 		log_error("geometry and message are incompatible");
1313 		return NULL;
1314 	}
1315 
1316 	if (dmt->sector && !dmt->message) {
1317 		log_error("message is required with sector");
1318 		return NULL;
1319 	}
1320 
1321 	if (dmt->newname)
1322 		len += strlen(dmt->newname) + 1;
1323 
1324 	if (dmt->message)
1325 		len += sizeof(struct dm_target_msg) + strlen(dmt->message) + 1;
1326 
1327 	if (dmt->geometry)
1328 		len += strlen(dmt->geometry) + 1;
1329 
1330 	/*
1331 	 * Give len a minimum size so that we have space to store
1332 	 * dependencies or status information.
1333 	 */
1334 	if (len < min_size)
1335 		len = min_size;
1336 
1337 	/* Increase buffer size if repeating because buffer was too small */
1338 	while (repeat_count--)
1339 		len *= 2;
1340 
1341 	if (!(dmi = dm_malloc(len)))
1342 		return NULL;
1343 
1344 	memset(dmi, 0, len);
1345 
1346 	version = &_cmd_data_v4[dmt->type].version;
1347 
1348 	dmi->version[0] = (*version)[0];
1349 	dmi->version[1] = (*version)[1];
1350 	dmi->version[2] = (*version)[2];
1351 
1352 	dmi->data_size = len;
1353 	dmi->data_start = sizeof(struct dm_ioctl);
1354 
1355 	if (dmt->minor >= 0) {
1356 		if (dmt->major <= 0) {
1357 			log_error("Missing major number for persistent device.");
1358 			goto bad;
1359 		}
1360 
1361 		if (!_dm_multiple_major_support && dmt->allow_default_major_fallback &&
1362 		    dmt->major != _dm_device_major) {
1363 			log_verbose("Overriding major number of %" PRIu32
1364 				    " with %" PRIu32 " for persistent device.",
1365 				    dmt->major, _dm_device_major);
1366 			dmt->major = _dm_device_major;
1367 		}
1368 
1369 		dmi->flags |= DM_PERSISTENT_DEV_FLAG;
1370 		dmi->dev = MKDEV(dmt->major, dmt->minor);
1371 	}
1372 
1373 	/* Does driver support device number referencing? */
1374 	if (_dm_version_minor < 3 && !dmt->dev_name && !dmt->uuid && dmi->dev) {
1375 		if (!_lookup_dev_name(dmi->dev, dmi->name, sizeof(dmi->name))) {
1376 			log_error("Unable to find name for device (%" PRIu32
1377 				  ":%" PRIu32 ")", dmt->major, dmt->minor);
1378 			goto bad;
1379 		}
1380 		log_verbose("device (%" PRIu32 ":%" PRIu32 ") is %s "
1381 			    "for compatibility with old kernel",
1382 			    dmt->major, dmt->minor, dmi->name);
1383 	}
1384 
1385 	/* FIXME Until resume ioctl supplies name, use dev_name for readahead */
1386 	if (dmt->dev_name && (dmt->type != DM_DEVICE_RESUME || dmt->minor < 0 ||
1387 			      dmt->major < 0))
1388 		strncpy(dmi->name, dmt->dev_name, sizeof(dmi->name));
1389 
1390 	if (dmt->uuid)
1391 		strncpy(dmi->uuid, dmt->uuid, sizeof(dmi->uuid));
1392 
1393 	if (dmt->type == DM_DEVICE_SUSPEND)
1394 		dmi->flags |= DM_SUSPEND_FLAG;
1395 	if (dmt->no_flush)
1396 		dmi->flags |= DM_NOFLUSH_FLAG;
1397 	if (dmt->read_only)
1398 		dmi->flags |= DM_READONLY_FLAG;
1399 	if (dmt->skip_lockfs)
1400 		dmi->flags |= DM_SKIP_LOCKFS_FLAG;
1401 	if (dmt->query_inactive_table) {
1402 		if (_dm_version_minor < 16)
1403 			log_warn("WARNING: Inactive table query unsupported "
1404 				 "by kernel.  It will use live table.");
1405 		dmi->flags |= DM_QUERY_INACTIVE_TABLE_FLAG;
1406 	}
1407 
1408 	dmi->target_count = count;
1409 	dmi->event_nr = dmt->event_nr;
1410 
1411 	b = (void *) (dmi + 1);
1412 	e = (void *) ((char *) dmi + len);
1413 
1414 	for (t = dmt->head; t; t = t->next)
1415 		if (!(b = _add_target(t, b, e)))
1416 			goto bad;
1417 
1418 	if (dmt->newname)
1419 		strcpy(b, dmt->newname);
1420 
1421 	if (dmt->message) {
1422 		tmsg = (struct dm_target_msg *) b;
1423 		tmsg->sector = dmt->sector;
1424 		strcpy(tmsg->message, dmt->message);
1425 	}
1426 
1427 	if (dmt->geometry)
1428 		strcpy(b, dmt->geometry);
1429 
1430 	return dmi;
1431 
1432       bad:
1433 	dm_free(dmi);
1434 	return NULL;
1435 }
1436 
_process_mapper_dir(struct dm_task * dmt)1437 static int _process_mapper_dir(struct dm_task *dmt)
1438 {
1439 	struct dirent *dirent;
1440 	DIR *d;
1441 	const char *dir;
1442 	int r = 1;
1443 
1444 	dir = dm_dir();
1445 	if (!(d = opendir(dir))) {
1446 		log_sys_error("opendir", dir);
1447 		return 0;
1448 	}
1449 
1450 	while ((dirent = readdir(d))) {
1451 		if (!strcmp(dirent->d_name, ".") ||
1452 		    !strcmp(dirent->d_name, "..") ||
1453 		    !strcmp(dirent->d_name, "control"))
1454 			continue;
1455 		dm_task_set_name(dmt, dirent->d_name);
1456 		dm_task_run(dmt);
1457 	}
1458 
1459 	if (closedir(d))
1460 		log_sys_error("closedir", dir);
1461 
1462 	return r;
1463 }
1464 
_process_all_v4(struct dm_task * dmt)1465 static int _process_all_v4(struct dm_task *dmt)
1466 {
1467 	struct dm_task *task;
1468 	struct dm_names *names;
1469 	unsigned next = 0;
1470 	int r = 1;
1471 
1472 	if (!(task = dm_task_create(DM_DEVICE_LIST)))
1473 		return 0;
1474 
1475 	if (!dm_task_run(task)) {
1476 		r = 0;
1477 		goto out;
1478 	}
1479 
1480 	if (!(names = dm_task_get_names(task))) {
1481 		r = 0;
1482 		goto out;
1483 	}
1484 
1485 	if (!names->dev)
1486 		goto out;
1487 
1488 	do {
1489 		names = (void *) names + next;
1490 		if (!dm_task_set_name(dmt, names->name)) {
1491 			r = 0;
1492 			goto out;
1493 		}
1494 		if (!dm_task_run(dmt))
1495 			r = 0;
1496 		next = names->next;
1497 	} while (next);
1498 
1499       out:
1500 	dm_task_destroy(task);
1501 	return r;
1502 }
1503 
_mknodes_v4(struct dm_task * dmt)1504 static int _mknodes_v4(struct dm_task *dmt)
1505 {
1506 	(void) _process_mapper_dir(dmt);
1507 
1508 	return _process_all_v4(dmt);
1509 }
1510 
1511 /*
1512  * If an operation that uses a cookie fails, decrement the
1513  * semaphore instead of udev.
1514  */
_udev_complete(struct dm_task * dmt)1515 static int _udev_complete(struct dm_task *dmt)
1516 {
1517 	uint32_t cookie;
1518 
1519 	if (dmt->cookie_set) {
1520 		/* strip flags from the cookie and use cookie magic instead */
1521 		cookie = (dmt->event_nr & ~DM_UDEV_FLAGS_MASK) |
1522 			  (DM_COOKIE_MAGIC << DM_UDEV_FLAGS_SHIFT);
1523 		return dm_udev_complete(cookie);
1524 	}
1525 
1526 	return 1;
1527 }
1528 
_create_and_load_v4(struct dm_task * dmt)1529 static int _create_and_load_v4(struct dm_task *dmt)
1530 {
1531 	struct dm_task *task;
1532 	int r;
1533 
1534 	/* Use new task struct to create the device */
1535 	if (!(task = dm_task_create(DM_DEVICE_CREATE))) {
1536 		log_error("Failed to create device-mapper task struct");
1537 		_udev_complete(dmt);
1538 		return 0;
1539 	}
1540 
1541 	/* Copy across relevant fields */
1542 	if (dmt->dev_name && !dm_task_set_name(task, dmt->dev_name)) {
1543 		dm_task_destroy(task);
1544 		_udev_complete(dmt);
1545 		return 0;
1546 	}
1547 
1548 	if (dmt->uuid && !dm_task_set_uuid(task, dmt->uuid)) {
1549 		dm_task_destroy(task);
1550 		_udev_complete(dmt);
1551 		return 0;
1552 	}
1553 
1554 	task->major = dmt->major;
1555 	task->minor = dmt->minor;
1556 	task->uid = dmt->uid;
1557 	task->gid = dmt->gid;
1558 	task->mode = dmt->mode;
1559 	/* FIXME: Just for udev_check in dm_task_run. Can we avoid this? */
1560 	task->event_nr = dmt->event_nr & DM_UDEV_FLAGS_MASK;
1561 	task->cookie_set = dmt->cookie_set;
1562 
1563 	r = dm_task_run(task);
1564 	dm_task_destroy(task);
1565 	if (!r) {
1566 		_udev_complete(dmt);
1567 		return 0;
1568 	}
1569 
1570 	/* Next load the table */
1571 	if (!(task = dm_task_create(DM_DEVICE_RELOAD))) {
1572 		log_error("Failed to create device-mapper task struct");
1573 		_udev_complete(dmt);
1574 		return 0;
1575 	}
1576 
1577 	/* Copy across relevant fields */
1578 	if (dmt->dev_name && !dm_task_set_name(task, dmt->dev_name)) {
1579 		dm_task_destroy(task);
1580 		_udev_complete(dmt);
1581 		return 0;
1582 	}
1583 
1584 	task->read_only = dmt->read_only;
1585 	task->head = dmt->head;
1586 	task->tail = dmt->tail;
1587 
1588 	r = dm_task_run(task);
1589 
1590 	task->head = NULL;
1591 	task->tail = NULL;
1592 	dm_task_destroy(task);
1593 	if (!r) {
1594 		_udev_complete(dmt);
1595 		goto revert;
1596 	}
1597 
1598 	/* Use the original structure last so the info will be correct */
1599 	dmt->type = DM_DEVICE_RESUME;
1600 	dm_free(dmt->uuid);
1601 	dmt->uuid = NULL;
1602 
1603 	r = dm_task_run(dmt);
1604 
1605 	if (r)
1606 		return r;
1607 
1608       revert:
1609  	dmt->type = DM_DEVICE_REMOVE;
1610 	dm_free(dmt->uuid);
1611 	dmt->uuid = NULL;
1612 	dmt->cookie_set = 0;
1613 
1614 	if (!dm_task_run(dmt))
1615 		log_error("Failed to revert device creation.");
1616 
1617 	return r;
1618 }
1619 
dm_task_get_existing_table_size(struct dm_task * dmt)1620 uint64_t dm_task_get_existing_table_size(struct dm_task *dmt)
1621 {
1622 	return dmt->existing_table_size;
1623 }
1624 
_reload_with_suppression_v4(struct dm_task * dmt)1625 static int _reload_with_suppression_v4(struct dm_task *dmt)
1626 {
1627 	struct dm_task *task;
1628 	struct target *t1, *t2;
1629 	int r;
1630 
1631 	/* New task to get existing table information */
1632 	if (!(task = dm_task_create(DM_DEVICE_TABLE))) {
1633 		log_error("Failed to create device-mapper task struct");
1634 		return 0;
1635 	}
1636 
1637 	/* Copy across relevant fields */
1638 	if (dmt->dev_name && !dm_task_set_name(task, dmt->dev_name)) {
1639 		dm_task_destroy(task);
1640 		return 0;
1641 	}
1642 
1643 	if (dmt->uuid && !dm_task_set_uuid(task, dmt->uuid)) {
1644 		dm_task_destroy(task);
1645 		return 0;
1646 	}
1647 
1648 	task->major = dmt->major;
1649 	task->minor = dmt->minor;
1650 
1651 	r = dm_task_run(task);
1652 
1653 	if (!r) {
1654 		dm_task_destroy(task);
1655 		return r;
1656 	}
1657 
1658 	/* Store existing table size */
1659 	t2 = task->head;
1660 	while (t2 && t2->next)
1661 		t2 = t2->next;
1662 	dmt->existing_table_size = t2 ? t2->start + t2->length : 0;
1663 
1664 	if ((task->dmi.v4->flags & DM_READONLY_FLAG) ? 1 : 0 != dmt->read_only)
1665 		goto no_match;
1666 
1667 	t1 = dmt->head;
1668 	t2 = task->head;
1669 
1670 	while (t1 && t2) {
1671 		while (t2->params[strlen(t2->params) - 1] == ' ')
1672 			t2->params[strlen(t2->params) - 1] = '\0';
1673 		if ((t1->start != t2->start) ||
1674 		    (t1->length != t2->length) ||
1675 		    (strcmp(t1->type, t2->type)) ||
1676 		    (strcmp(t1->params, t2->params)))
1677 			goto no_match;
1678 		t1 = t1->next;
1679 		t2 = t2->next;
1680 	}
1681 
1682 	if (!t1 && !t2) {
1683 		dmt->dmi.v4 = task->dmi.v4;
1684 		task->dmi.v4 = NULL;
1685 		dm_task_destroy(task);
1686 		return 1;
1687 	}
1688 
1689 no_match:
1690 	dm_task_destroy(task);
1691 
1692 	/* Now do the original reload */
1693 	dmt->suppress_identical_reload = 0;
1694 	r = dm_task_run(dmt);
1695 
1696 	return r;
1697 }
1698 
_do_dm_ioctl(struct dm_task * dmt,unsigned command,unsigned repeat_count)1699 static struct dm_ioctl *_do_dm_ioctl(struct dm_task *dmt, unsigned command,
1700 				     unsigned repeat_count)
1701 {
1702 	struct dm_ioctl *dmi;
1703 
1704 	dmi = _flatten(dmt, repeat_count);
1705 	if (!dmi) {
1706 		log_error("Couldn't create ioctl argument.");
1707 		return NULL;
1708 	}
1709 
1710 	if (dmt->type == DM_DEVICE_TABLE)
1711 		dmi->flags |= DM_STATUS_TABLE_FLAG;
1712 
1713 	dmi->flags |= DM_EXISTS_FLAG;	/* FIXME */
1714 
1715 	if (dmt->no_open_count)
1716 		dmi->flags |= DM_SKIP_BDGET_FLAG;
1717 
1718 	/*
1719 	 * Prevent udev vs. libdevmapper race when processing nodes and
1720 	 * symlinks. This can happen when the udev rules are installed and
1721 	 * udev synchronisation code is enabled in libdevmapper but the
1722 	 * software using libdevmapper does not make use of it (by not calling
1723 	 * dm_task_set_cookie before). We need to instruct the udev rules not
1724 	 * to be applied at all in this situation so we can gracefully fallback
1725 	 * to libdevmapper's node and symlink creation code.
1726 	 */
1727 	if (dm_udev_get_sync_support() && !dmt->cookie_set &&
1728 	    (dmt->type == DM_DEVICE_RESUME ||
1729 	     dmt->type == DM_DEVICE_REMOVE ||
1730 	     dmt->type == DM_DEVICE_RENAME)) {
1731 		log_debug("Cookie value is not set while trying to call "
1732 			  "DM_DEVICE_RESUME, DM_DEVICE_REMOVE or DM_DEVICE_RENAME "
1733 			  "ioctl. Please, consider using libdevmapper's udev "
1734 			  "synchronisation interface or disable it explicitly "
1735 			  "by calling dm_udev_set_sync_support(0).");
1736 		log_debug("Switching off device-mapper and all subsystem related "
1737 			  "udev rules. Falling back to libdevmapper node creation.");
1738 		/*
1739 		 * Disable general dm and subsystem rules but keep dm disk rules
1740 		 * if not flagged out explicitly before. We need /dev/disk content
1741 		 * for the software that expects it.
1742 		*/
1743 		dmi->event_nr |= (DM_UDEV_DISABLE_DM_RULES_FLAG |
1744 				  DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG) <<
1745 				 DM_UDEV_FLAGS_SHIFT;
1746 	}
1747 
1748 	log_debug("dm %s %s %s%s%s %s%.0d%s%.0d%s"
1749 		  "%s%c%c%s%s %.0" PRIu64 " %s [%u]",
1750 		  _cmd_data_v4[dmt->type].name,
1751 		  dmi->name, dmi->uuid, dmt->newname ? " " : "",
1752 		  dmt->newname ? dmt->newname : "",
1753 		  dmt->major > 0 ? "(" : "",
1754 		  dmt->major > 0 ? dmt->major : 0,
1755 		  dmt->major > 0 ? ":" : "",
1756 		  dmt->minor > 0 ? dmt->minor : 0,
1757 		  dmt->major > 0 && dmt->minor == 0 ? "0" : "",
1758 		  dmt->major > 0 ? ") " : "",
1759 		  dmt->no_open_count ? 'N' : 'O',
1760 		  dmt->no_flush ? 'N' : 'F',
1761 		  dmt->skip_lockfs ? "S " : "",
1762 		  dmt->query_inactive_table ? "I " : "",
1763 		  dmt->sector, dmt->message ? dmt->message : "",
1764 		  dmi->data_size);
1765 #ifdef DM_IOCTLS
1766 	if (ioctl(_control_fd, command, dmi) < 0) {
1767 		if (errno == ENXIO && ((dmt->type == DM_DEVICE_INFO) ||
1768 				       (dmt->type == DM_DEVICE_MKNODES) ||
1769 				       (dmt->type == DM_DEVICE_STATUS)))
1770 			dmi->flags &= ~DM_EXISTS_FLAG;	/* FIXME */
1771 		else {
1772 			if (_log_suppress)
1773 				log_verbose("device-mapper: %s ioctl "
1774 					    "failed: %s",
1775 				    	    _cmd_data_v4[dmt->type].name,
1776 					    strerror(errno));
1777 			else
1778 				log_error("device-mapper: %s ioctl "
1779 					  "failed: %s",
1780 				    	   _cmd_data_v4[dmt->type].name,
1781 					  strerror(errno));
1782 			dm_free(dmi);
1783 			return NULL;
1784 		}
1785 	}
1786 #else /* Userspace alternative for testing */
1787 #endif
1788 	return dmi;
1789 }
1790 
dm_task_update_nodes(void)1791 void dm_task_update_nodes(void)
1792 {
1793 	update_devs();
1794 }
1795 
dm_task_run(struct dm_task * dmt)1796 int dm_task_run(struct dm_task *dmt)
1797 {
1798 	struct dm_ioctl *dmi;
1799 	unsigned command;
1800 	int check_udev;
1801 
1802 #ifdef DM_COMPAT
1803 	if (_dm_version == 1)
1804 		return _dm_task_run_v1(dmt);
1805 #endif
1806 
1807 	if ((unsigned) dmt->type >=
1808 	    (sizeof(_cmd_data_v4) / sizeof(*_cmd_data_v4))) {
1809 		log_error("Internal error: unknown device-mapper task %d",
1810 			  dmt->type);
1811 		return 0;
1812 	}
1813 
1814 	command = _cmd_data_v4[dmt->type].cmd;
1815 
1816 	/* Old-style creation had a table supplied */
1817 	if (dmt->type == DM_DEVICE_CREATE && dmt->head)
1818 		return _create_and_load_v4(dmt);
1819 
1820 	if (dmt->type == DM_DEVICE_MKNODES && !dmt->dev_name &&
1821 	    !dmt->uuid && dmt->major <= 0)
1822 		return _mknodes_v4(dmt);
1823 
1824 	if ((dmt->type == DM_DEVICE_RELOAD) && dmt->suppress_identical_reload)
1825 		return _reload_with_suppression_v4(dmt);
1826 
1827 	if (!_open_control()) {
1828 		_udev_complete(dmt);
1829 		return 0;
1830 	}
1831 
1832 	/* FIXME Detect and warn if cookie set but should not be. */
1833 repeat_ioctl:
1834 	if (!(dmi = _do_dm_ioctl(dmt, command, _ioctl_buffer_double_factor))) {
1835 		_udev_complete(dmt);
1836 		return 0;
1837 	}
1838 
1839 	if (dmi->flags & DM_BUFFER_FULL_FLAG) {
1840 		switch (dmt->type) {
1841 		case DM_DEVICE_LIST_VERSIONS:
1842 		case DM_DEVICE_LIST:
1843 		case DM_DEVICE_DEPS:
1844 		case DM_DEVICE_STATUS:
1845 		case DM_DEVICE_TABLE:
1846 		case DM_DEVICE_WAITEVENT:
1847 			_ioctl_buffer_double_factor++;
1848 			dm_free(dmi);
1849 			goto repeat_ioctl;
1850 		default:
1851 			log_error("WARNING: libdevmapper buffer too small for data");
1852 		}
1853 	}
1854 
1855 	check_udev = dmt->cookie_set &&
1856 		     !(dmt->event_nr >> DM_UDEV_FLAGS_SHIFT &
1857 		       DM_UDEV_DISABLE_DM_RULES_FLAG);
1858 
1859 	switch (dmt->type) {
1860 	case DM_DEVICE_CREATE:
1861 		if (dmt->dev_name && *dmt->dev_name)
1862 			add_dev_node(dmt->dev_name, MAJOR(dmi->dev),
1863 				     MINOR(dmi->dev), dmt->uid, dmt->gid,
1864 				     dmt->mode, check_udev);
1865 		break;
1866 	case DM_DEVICE_REMOVE:
1867 		/* FIXME Kernel needs to fill in dmi->name */
1868 		if (dmt->dev_name)
1869 			rm_dev_node(dmt->dev_name, check_udev);
1870 		break;
1871 
1872 	case DM_DEVICE_RENAME:
1873 		/* FIXME Kernel needs to fill in dmi->name */
1874 		if (dmt->dev_name)
1875 			rename_dev_node(dmt->dev_name, dmt->newname,
1876 					check_udev);
1877 		break;
1878 
1879 	case DM_DEVICE_RESUME:
1880 		/* FIXME Kernel needs to fill in dmi->name */
1881 		set_dev_node_read_ahead(dmt->dev_name, dmt->read_ahead,
1882 					dmt->read_ahead_flags);
1883 		break;
1884 
1885 	case DM_DEVICE_MKNODES:
1886 		if (dmi->flags & DM_EXISTS_FLAG)
1887 			add_dev_node(dmi->name, MAJOR(dmi->dev),
1888 				     MINOR(dmi->dev), dmt->uid,
1889 				     dmt->gid, dmt->mode, 0);
1890 		else if (dmt->dev_name)
1891 			rm_dev_node(dmt->dev_name, 0);
1892 		break;
1893 
1894 	case DM_DEVICE_STATUS:
1895 	case DM_DEVICE_TABLE:
1896 	case DM_DEVICE_WAITEVENT:
1897 		if (!_unmarshal_status(dmt, dmi))
1898 			goto bad;
1899 		break;
1900 	}
1901 
1902 	/* Was structure reused? */
1903 	if (dmt->dmi.v4)
1904 		dm_free(dmt->dmi.v4);
1905 	dmt->dmi.v4 = dmi;
1906 	return 1;
1907 
1908       bad:
1909 	dm_free(dmi);
1910 	return 0;
1911 }
1912 
dm_lib_release(void)1913 void dm_lib_release(void)
1914 {
1915 	if (_control_fd != -1) {
1916 		close(_control_fd);
1917 		_control_fd = -1;
1918 	}
1919 	update_devs();
1920 }
1921 
1922 void dm_pools_check_leaks(void);
1923 
dm_lib_exit(void)1924 void dm_lib_exit(void)
1925 {
1926 	dm_lib_release();
1927 	if (_dm_bitset)
1928 		dm_bitset_destroy(_dm_bitset);
1929 	_dm_bitset = NULL;
1930 	dm_pools_check_leaks();
1931 	dm_dump_memory();
1932 	_version_ok = 1;
1933 	_version_checked = 0;
1934 }
1935