1 /*-
2  * Copyright (c) 2005-2006 The FreeBSD Project
3  * All rights reserved.
4  *
5  * Author: Victor Cruceru <soc-victor@freebsd.org>
6  *
7  * Redistribution of this software and documentation and use in source and
8  * binary forms, with or without modification, are permitted provided that
9  * the following conditions are met:
10  *
11  * 1. Redistributions of source code or documentation must retain the above
12  *    copyright notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 /*
33  * Host Resources MIB for SNMPd. Implementation for the hrDiskStorageTable
34  */
35 
36 #include <sys/types.h>
37 #include <sys/param.h>
38 #include <sys/ata.h>
39 #include <sys/disk.h>
40 #include <sys/linker.h>
41 #include <sys/mdioctl.h>
42 #include <sys/module.h>
43 #include <sys/sysctl.h>
44 
45 #include <assert.h>
46 #include <ctype.h>
47 #include <err.h>
48 #include <errno.h>
49 #include <paths.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <syslog.h>
53 #include <unistd.h>
54 
55 #include "hostres_snmp.h"
56 #include "hostres_oid.h"
57 #include "hostres_tree.h"
58 
59 enum hrDiskStrorageAccess {
60 	DS_READ_WRITE = 1,
61 	DS_READ_ONLY  = 2
62 };
63 
64 enum hrDiskStrorageMedia {
65 	DSM_OTHER	=	1,
66 	DSM_UNKNOWN	=	2,
67 	DSM_HARDDISK	=	3,
68 	DSM_FLOPPYDISK	=	4,
69 	DSM_OPTICALDISKROM=	5,
70 	DSM_OPTICALDISKWORM=	6,
71 	DSM_OPTICALDISKRW=	7,
72 	DSM_RAMDISK	=	8
73 };
74 
75 /*
76  * This structure is used to hold a SNMP table entry for HOST-RESOURCES-MIB's
77  * hrDiskStorageTable. Note that index is external being allocated and
78  * maintained by the hrDeviceTable code.
79  *
80  * NOTE: according to MIB removable means removable media, not the
81  * device itself (like a USB card reader)
82  */
83 struct disk_entry {
84 	int32_t		index;
85 	int32_t		access;		/* enum hrDiskStrorageAccess */
86 	int32_t		media;		/* enum hrDiskStrorageMedia*/
87 	int32_t		removable; 	/* enum snmpTCTruthValue*/
88 	int32_t		capacity;
89 	TAILQ_ENTRY(disk_entry) link;
90 	/*
91 	 * next items are not from the SNMP mib table, only to be used
92 	 * internally
93 	 */
94 #define HR_DISKSTORAGE_FOUND	0x001
95 #define HR_DISKSTORAGE_ATA	0x002 /* belongs to the ATA subsystem */
96 #define HR_DISKSTORAGE_MD	0x004 /* it is a MD (memory disk) */
97 	uint32_t	flags;
98 	uint64_t	r_tick;
99 	u_char		dev_name[32];	/* device name, i.e. "ad4" or "acd0" */
100 };
101 TAILQ_HEAD(disk_tbl, disk_entry);
102 
103 /* the head of the list with hrDiskStorageTable's entries */
104 static struct disk_tbl disk_tbl =
105     TAILQ_HEAD_INITIALIZER(disk_tbl);
106 
107 /* last tick when hrFSTable was updated */
108 static uint64_t disk_storage_tick;
109 
110 /* minimum number of ticks between refreshs */
111 uint32_t disk_storage_tbl_refresh = HR_DISK_TBL_REFRESH * 100;
112 
113 /* fd for "/dev/mdctl"*/
114 static int md_fd = -1;
115 
116 /* buffer for sysctl("kern.disks") */
117 static char *disk_list;
118 static size_t disk_list_len;
119 
120 /* some constants */
121 static const struct asn_oid OIDX_hrDeviceDiskStorage_c =
122     OIDX_hrDeviceDiskStorage;
123 
124 /**
125  * Load the MD driver if it isn't loaded already.
126  */
127 static void
128 mdmaybeload(void)
129 {
130 	char name1[64], name2[64];
131 
132 	snprintf(name1, sizeof(name1), "g_%s", MD_NAME);
133 	snprintf(name2, sizeof(name2), "geom_%s", MD_NAME);
134 	if (modfind(name1) == -1) {
135 		/* Not present in kernel, try loading it. */
136 		if (kldload(name2) == -1 || modfind(name1) == -1) {
137 			if (errno != EEXIST) {
138 				errx(EXIT_FAILURE,
139 				    "%s module not available!", name2);
140 			}
141 		}
142 	}
143 }
144 
145 /**
146  * Create a new entry into the DiskStorageTable.
147  */
148 static struct disk_entry *
149 disk_entry_create(const struct device_entry *devEntry)
150 {
151 	struct disk_entry *entry;
152 
153 	assert(devEntry != NULL);
154 	if (devEntry == NULL)
155 		return NULL;
156 
157 	if ((entry = malloc(sizeof(*entry))) == NULL) {
158 		syslog(LOG_WARNING, "hrDiskStorageTable: %s: %m", __func__);
159 		return (NULL);
160 	}
161 
162 	memset(entry, 0, sizeof(*entry));
163 	entry->index = devEntry->index;
164 	INSERT_OBJECT_INT(entry, &disk_tbl);
165 
166 	return (entry);
167 }
168 
169 /**
170  * Delete a disk table entry.
171  */
172 static void
173 disk_entry_delete(struct disk_entry *entry)
174 {
175 	struct device_entry *devEntry;
176 
177 	assert(entry != NULL);
178 	TAILQ_REMOVE(&disk_tbl, entry, link);
179 
180 	devEntry = device_find_by_index(entry->index);
181 
182 	free(entry);
183 
184 	/*
185 	 * Also delete the respective device entry -
186 	 * this is needed for disk devices that are not
187 	 * detected by libdevinfo
188 	 */
189 	if (devEntry != NULL &&
190 	    (devEntry->flags & HR_DEVICE_IMMUTABLE) == HR_DEVICE_IMMUTABLE)
191 		device_entry_delete(devEntry);
192 }
193 
194 /**
195  * Find a disk storage entry given its index.
196  */
197 static struct disk_entry *
198 disk_find_by_index(int32_t idx)
199 {
200 	struct disk_entry *entry;
201 
202 	TAILQ_FOREACH(entry, &disk_tbl, link)
203 		if (entry->index == idx)
204 			return (entry);
205 
206 	return (NULL);
207 }
208 
209 /**
210  * Get the disk parameters
211  */
212 static void
213 disk_query_disk(struct disk_entry *entry)
214 {
215 	char dev_path[128];
216 	int fd;
217 	off_t mediasize;
218 
219 	if (entry == NULL || entry->dev_name[0] == '\0')
220 		return;
221 
222 	snprintf(dev_path, sizeof(dev_path),
223 	    "%s%s", _PATH_DEV, entry->dev_name);
224 	entry->capacity = 0;
225 
226 	HRDBG("OPENING device %s", dev_path);
227 	if ((fd = open(dev_path, O_RDONLY|O_NONBLOCK)) == -1) {
228 		HRDBG("OPEN device %s failed: %s", dev_path, strerror(errno));
229 		return;
230 	}
231 
232 	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0) {
233 		HRDBG("DIOCGMEDIASIZE for device %s failed: %s",
234 		    dev_path, strerror(errno));
235 		(void)close(fd);
236 		return;
237 	}
238 
239 	mediasize = mediasize / 1024;
240 	entry->capacity = (mediasize > INT_MAX ? INT_MAX : mediasize);
241 	partition_tbl_handle_disk(entry->index, entry->dev_name);
242 
243 	(void)close(fd);
244 }
245 
246 /**
247  * Find all ATA disks in the device table.
248  */
249 static void
250 disk_OS_get_ATA_disks(void)
251 {
252 	struct device_map_entry *map;
253 	struct device_entry *entry;
254 	struct disk_entry *disk_entry;
255 	const struct disk_entry *found;
256 
257 	/* Things we know are ata disks */
258 	static const struct disk_entry lookup[] = {
259 		{
260 		    .dev_name = "ad",
261 		    .media = DSM_HARDDISK,
262 		    .removable = SNMP_FALSE
263 		},
264 		{
265 		    .dev_name = "ar",
266 		    .media = DSM_OTHER,
267 		    .removable = SNMP_FALSE
268 		},
269 		{
270 		    .dev_name = "acd",
271 		    .media = DSM_OPTICALDISKROM,
272 		    .removable = SNMP_TRUE
273 		},
274 		{
275 		    .dev_name = "afd",
276 		    .media = DSM_FLOPPYDISK,
277 		    .removable = SNMP_TRUE
278 		},
279 		{
280 		    .dev_name = "ast",
281 		    .media = DSM_OTHER,
282 		    .removable = SNMP_TRUE
283 		},
284 
285 		{ .media = DSM_UNKNOWN }
286 	};
287 
288 	/* Walk over the device table looking for ata disks */
289 	STAILQ_FOREACH(map, &device_map, link) {
290 		for (found = lookup; found->media != DSM_UNKNOWN; found++) {
291 			if (strncmp(map->name_key, found->dev_name,
292 			    strlen(found->dev_name)) != 0)
293 				continue;
294 
295 			/*
296 			 * Avoid false disk devices. For example adw(4) and
297 			 * adv(4) - they are not disks!
298 			 */
299 			if (strlen(map->name_key) > strlen(found->dev_name) &&
300 			    !isdigit(map->name_key[strlen(found->dev_name)]))
301 				continue;
302 
303 			/* First get the entry from the hrDeviceTbl */
304 			entry = map->entry_p;
305 			entry->type = &OIDX_hrDeviceDiskStorage_c;
306 
307 			/* Then check hrDiskStorage table for this device */
308 			disk_entry = disk_find_by_index(entry->index);
309 			if (disk_entry == NULL) {
310 				disk_entry = disk_entry_create(entry);
311 				if (disk_entry == NULL)
312 					continue;
313 
314 				disk_entry->access = DS_READ_WRITE;
315 				strlcpy(disk_entry->dev_name, entry->name,
316 				    sizeof(disk_entry->dev_name));
317 
318 				disk_entry->media = found->media;
319 				disk_entry->removable = found->removable;
320 			}
321 
322 			disk_entry->flags |= HR_DISKSTORAGE_FOUND;
323 			disk_entry->flags |= HR_DISKSTORAGE_ATA;
324 
325 			disk_query_disk(disk_entry);
326 			disk_entry->r_tick = this_tick;
327 		}
328 	}
329 }
330 
331 /**
332  * Find MD disks in the device table.
333  */
334 static void
335 disk_OS_get_MD_disks(void)
336 {
337 	struct device_map_entry *map;
338 	struct device_entry *entry;
339 	struct disk_entry *disk_entry;
340 	struct md_ioctl mdio;
341 	int unit;
342 
343 	if (md_fd <= 0)
344 		return;
345 
346 	/* Look for md devices */
347 	STAILQ_FOREACH(map, &device_map, link) {
348 		if (sscanf(map->name_key, "md%d", &unit) != 1)
349 			continue;
350 
351 		/* First get the entry from the hrDeviceTbl */
352 		entry = device_find_by_index(map->hrIndex);
353 		entry->type = &OIDX_hrDeviceDiskStorage_c;
354 
355 		/* Then check hrDiskStorage table for this device */
356 		disk_entry = disk_find_by_index(entry->index);
357 		if (disk_entry == NULL) {
358 			disk_entry = disk_entry_create(entry);
359 			if (disk_entry == NULL)
360 				continue;
361 
362 			memset(&mdio, 0, sizeof(mdio));
363 			mdio.md_version = MDIOVERSION;
364 			mdio.md_unit = unit;
365 
366 			if (ioctl(md_fd, MDIOCQUERY, &mdio) < 0) {
367 				syslog(LOG_ERR,
368 				    "hrDiskStorageTable: Couldnt ioctl");
369 				continue;
370 			}
371 
372 			if ((mdio.md_options & MD_READONLY) == MD_READONLY)
373 				disk_entry->access = DS_READ_ONLY;
374 			else
375 				disk_entry->access = DS_READ_WRITE;
376 
377 			strlcpy(disk_entry->dev_name, entry->name,
378 			    sizeof(disk_entry->dev_name));
379 
380 			disk_entry->media = DSM_RAMDISK;
381 			disk_entry->removable = SNMP_FALSE;
382 		}
383 
384 		disk_entry->flags |= HR_DISKSTORAGE_FOUND;
385 		disk_entry->flags |= HR_DISKSTORAGE_MD;
386 		disk_entry->r_tick = this_tick;
387 	}
388 }
389 
390 /**
391  * Find rest of disks
392  */
393 static void
394 disk_OS_get_disks(void)
395 {
396 	size_t disk_cnt = 0;
397 	struct device_entry *entry;
398 	struct disk_entry *disk_entry;
399 
400 	size_t need = 0;
401 
402 	if (sysctlbyname("kern.disks", NULL, &need, NULL, 0) == -1) {
403 		syslog(LOG_ERR, "%s: sysctl_1 kern.disks failed: %m", __func__);
404 		return;
405 	}
406 
407 	if (need == 0)
408 		return;
409 
410 	if (disk_list_len != need + 1 || disk_list == NULL) {
411 		disk_list_len = need + 1;
412 		disk_list = reallocf(disk_list, disk_list_len);
413 	}
414 
415 	if (disk_list == NULL) {
416 		syslog(LOG_ERR, "%s: reallocf failed", __func__);
417 		disk_list_len = 0;
418 		return;
419 	}
420 
421 	memset(disk_list, 0, disk_list_len);
422 
423 	if (sysctlbyname("kern.disks", disk_list, &need, NULL, 0) == -1 ||
424 	    disk_list[0] == 0) {
425 		syslog(LOG_ERR, "%s: sysctl_2 kern.disks failed: %m", __func__);
426 		return;
427 	}
428 
429 	for (disk_cnt = 0; disk_cnt < need; disk_cnt++) {
430 		char *disk = NULL;
431 		char disk_device[128] = "";
432 
433 		disk = strsep(&disk_list, " ");
434 		if (disk == NULL)
435 			break;
436 
437 		snprintf(disk_device, sizeof(disk_device),
438 		    "%s%s", _PATH_DEV, disk);
439 
440 		/* First check if the disk is in the hrDeviceTable. */
441 		if ((entry = device_find_by_name(disk)) == NULL) {
442 			/*
443 			 * not found there - insert it as immutable
444 			 */
445 			syslog(LOG_WARNING, "%s: device '%s' not in "
446 			    "device list", __func__, disk);
447 
448 			if ((entry = device_entry_create(disk, "", "")) == NULL)
449 				continue;
450 
451 			entry->flags |= HR_DEVICE_IMMUTABLE;
452 		}
453 
454 		entry->type = &OIDX_hrDeviceDiskStorage_c;
455 
456 		/* Then check hrDiskStorage table for this device */
457 		disk_entry = disk_find_by_index(entry->index);
458 		if (disk_entry == NULL) {
459 			disk_entry = disk_entry_create(entry);
460 			if (disk_entry == NULL)
461 				continue;
462 		}
463 
464 		disk_entry->flags |= HR_DISKSTORAGE_FOUND;
465 
466 		if ((disk_entry->flags & HR_DISKSTORAGE_ATA) ||
467 		    (disk_entry->flags & HR_DISKSTORAGE_MD)) {
468 			/*
469 			 * ATA/MD detection is running before this one,
470 			 * so don't waste the time here
471 			 */
472 			continue;
473 		}
474 
475 		disk_entry->access = DS_READ_WRITE;
476 		disk_entry->media = DSM_UNKNOWN;
477 		disk_entry->removable = SNMP_FALSE;
478 
479 		if (strncmp(disk_entry->dev_name, "da", 2) == 0) {
480 			disk_entry->media = DSM_HARDDISK;
481 			disk_entry->removable = SNMP_FALSE;
482 		} else if (strncmp(disk_entry->dev_name, "cd", 2) == 0) {
483 			disk_entry->media = DSM_OPTICALDISKROM;
484 			disk_entry->removable = SNMP_TRUE;
485 	 	} else {
486 			disk_entry->media = DSM_UNKNOWN;
487 			disk_entry->removable = SNMP_FALSE;
488 		}
489 
490 		strlcpy((char *)disk_entry->dev_name, disk,
491 		    sizeof(disk_entry->dev_name));
492 
493 		disk_query_disk(disk_entry);
494 		disk_entry->r_tick = this_tick;
495 	}
496 }
497 
498 /**
499  * Refresh routine for hrDiskStorageTable
500  * Usable for polling the system for any changes.
501  */
502 void
503 refresh_disk_storage_tbl(int force)
504 {
505 	struct disk_entry *entry, *entry_tmp;
506 
507 	if (disk_storage_tick != 0 && !force &&
508 	    this_tick - disk_storage_tick < disk_storage_tbl_refresh) {
509 		HRDBG("no refresh needed");
510 		return;
511 	}
512 
513 	partition_tbl_pre_refresh();
514 
515 	/* mark each entry as missing */
516 	TAILQ_FOREACH(entry, &disk_tbl, link)
517 		entry->flags &= ~HR_DISKSTORAGE_FOUND;
518 
519 	disk_OS_get_ATA_disks();	/* this must be called first ! */
520 	disk_OS_get_MD_disks();
521 	disk_OS_get_disks();
522 
523 	/*
524 	 * Purge items that disappeared
525 	 */
526 	TAILQ_FOREACH_SAFE(entry, &disk_tbl, link, entry_tmp)
527 		if (!(entry->flags & HR_DISKSTORAGE_FOUND))
528 			/* XXX remove IMMUTABLE entries that have disappeared */
529 			disk_entry_delete(entry);
530 
531 	disk_storage_tick = this_tick;
532 
533 	partition_tbl_post_refresh();
534 
535 	HRDBG("refresh DONE");
536 }
537 
538 /*
539  * Init the things for both of hrDiskStorageTable
540  */
541 int
542 init_disk_storage_tbl(void)
543 {
544 	char mddev[32] = "";
545 
546 	/* Try to load md.ko if not loaded already */
547 	mdmaybeload();
548 
549 	md_fd = -1;
550 	snprintf(mddev, sizeof(mddev) - 1, "%s%s", _PATH_DEV, MDCTL_NAME);
551 	if ((md_fd = open(mddev, O_RDWR)) == -1) {
552 		syslog(LOG_ERR, "open %s failed - will not include md(4) "
553 		    "info: %m", mddev);
554 	}
555 
556 	refresh_disk_storage_tbl(1);
557 
558 	return (0);
559 }
560 
561 /*
562  * Finalization routine for hrDiskStorageTable
563  * It destroys the lists and frees any allocated heap memory
564  */
565 void
566 fini_disk_storage_tbl(void)
567 {
568 	struct disk_entry *n1;
569 
570 	while ((n1 = TAILQ_FIRST(&disk_tbl)) != NULL) {
571 		TAILQ_REMOVE(&disk_tbl, n1, link);
572 		free(n1);
573 	}
574 
575 	free(disk_list);
576 
577 	if (md_fd > 0) {
578 		if (close(md_fd) == -1)
579 			syslog(LOG_ERR,"close (/dev/mdctl) failed: %m");
580 		md_fd = -1;
581 	}
582 }
583 
584 /*
585  * This is the implementation for a generated (by our SNMP "compiler" tool)
586  * function prototype, see hostres_tree.h
587  * It handles the SNMP operations for hrDiskStorageTable
588  */
589 int
590 op_hrDiskStorageTable(struct snmp_context *ctx __unused,
591     struct snmp_value *value, u_int sub, u_int iidx __unused,
592     enum snmp_op curr_op)
593 {
594 	struct disk_entry *entry;
595 
596 	refresh_disk_storage_tbl(0);
597 
598 	switch (curr_op) {
599 
600 	case SNMP_OP_GETNEXT:
601 		if ((entry = NEXT_OBJECT_INT(&disk_tbl,
602 		    &value->var, sub)) == NULL)
603 			return (SNMP_ERR_NOSUCHNAME);
604 		value->var.len = sub + 1;
605 		value->var.subs[sub] = entry->index;
606 		goto get;
607 
608 	case SNMP_OP_GET:
609 		if ((entry = FIND_OBJECT_INT(&disk_tbl,
610 		    &value->var, sub)) == NULL)
611 			return (SNMP_ERR_NOSUCHNAME);
612 		goto get;
613 
614 	case SNMP_OP_SET:
615 		if ((entry = FIND_OBJECT_INT(&disk_tbl,
616 		    &value->var, sub)) == NULL)
617 			return (SNMP_ERR_NO_CREATION);
618 		return (SNMP_ERR_NOT_WRITEABLE);
619 
620 	case SNMP_OP_ROLLBACK:
621 	case SNMP_OP_COMMIT:
622 	  	abort();
623 	}
624 	abort();
625 
626   get:
627 	switch (value->var.subs[sub - 1]) {
628 
629 	case LEAF_hrDiskStorageAccess:
630 	  	value->v.integer = entry->access;
631 	  	return (SNMP_ERR_NOERROR);
632 
633 	case LEAF_hrDiskStorageMedia:
634 	  	value->v.integer = entry->media;
635 	  	return (SNMP_ERR_NOERROR);
636 
637 	case LEAF_hrDiskStorageRemoveble:
638 	  	value->v.integer = entry->removable;
639 	  	return (SNMP_ERR_NOERROR);
640 
641 	case LEAF_hrDiskStorageCapacity:
642 	  	value->v.integer = entry->capacity;
643 	  	return (SNMP_ERR_NOERROR);
644 	}
645 	abort();
646 }
647