xref: /freebsd/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_diskstorage_tbl.c (revision 3d11b6c8f01e1fca5936a11d6996448467851a94)
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 
176 	assert(entry != NULL);
177 
178 	TAILQ_REMOVE(&disk_tbl, entry, link);
179 	free(entry);
180 }
181 
182 /**
183  * Find a disk storage entry given its index.
184  */
185 static struct disk_entry *
186 disk_find_by_index(int32_t idx)
187 {
188 	struct disk_entry *entry;
189 
190 	TAILQ_FOREACH(entry, &disk_tbl, link)
191 		if (entry->index == idx)
192 			return (entry);
193 
194 	return (NULL);
195 }
196 
197 /**
198  * Get the disk parameters
199  */
200 static void
201 disk_query_disk(struct disk_entry *entry)
202 {
203 	char dev_path[128];
204 	int fd;
205 	off_t mediasize;
206 
207 	if (entry == NULL || entry->dev_name[0] == '\0')
208 		return;
209 
210 	snprintf(dev_path, sizeof(dev_path),
211 	    "%s%s", _PATH_DEV, entry->dev_name);
212 	entry->capacity = 0;
213 
214 	HRDBG("OPENING device %s", dev_path);
215 	if ((fd = open(dev_path, O_RDONLY|O_NONBLOCK)) == -1) {
216 		HRDBG("OPEN device %s failed: %s", dev_path, strerror(errno));
217 		return;
218 	}
219 
220 	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0) {
221 		HRDBG("DIOCGMEDIASIZE for device %s failed: %s",
222 		    dev_path, strerror(errno));
223 		(void)close(fd);
224 		return;
225 	}
226 
227 	mediasize = mediasize / 1024;
228 	entry->capacity = (mediasize > INT_MAX ? INT_MAX : mediasize);
229 	partition_tbl_handle_disk(entry->index, entry->dev_name);
230 
231 	(void)close(fd);
232 }
233 
234 /**
235  * Find all ATA disks in the device table.
236  */
237 static void
238 disk_OS_get_ATA_disks(void)
239 {
240 	struct device_map_entry *map;
241 	struct device_entry *entry;
242 	struct disk_entry *disk_entry;
243 	const struct disk_entry *found;
244 
245 	/* Things we know are ata disks */
246 	static const struct disk_entry lookup[] = {
247 		{
248 		    .dev_name = "ad",
249 		    .media = DSM_HARDDISK,
250 		    .removable = SNMP_FALSE
251 		},
252 		{
253 		    .dev_name = "ar",
254 		    .media = DSM_OTHER,
255 		    .removable = SNMP_FALSE
256 		},
257 		{
258 		    .dev_name = "acd",
259 		    .media = DSM_OPTICALDISKROM,
260 		    .removable = SNMP_TRUE
261 		},
262 		{
263 		    .dev_name = "afd",
264 		    .media = DSM_FLOPPYDISK,
265 		    .removable = SNMP_TRUE
266 		},
267 		{
268 		    .dev_name = "ast",
269 		    .media = DSM_OTHER,
270 		    .removable = SNMP_TRUE
271 		},
272 
273 		{ .media = DSM_UNKNOWN }
274 	};
275 
276 	/* Walk over the device table looking for ata disks */
277 	STAILQ_FOREACH(map, &device_map, link) {
278 		for (found = lookup; found->media != DSM_UNKNOWN; found++) {
279 			if (strncmp(map->name_key, found->dev_name,
280 			    strlen(found->dev_name)) != 0)
281 				continue;
282 
283 			/*
284 			 * Avoid false disk devices. For example adw(4) and
285 			 * adv(4) - they are not disks!
286 			 */
287 			if (strlen(map->name_key) > strlen(found->dev_name) &&
288 			    !isdigit(map->name_key[strlen(found->dev_name)]))
289 				continue;
290 
291 			/* First get the entry from the hrDeviceTbl */
292 			entry = map->entry_p;
293 			entry->type = OIDX_hrDeviceDiskStorage_c;
294 
295 			/* Then check hrDiskStorage table for this device */
296 			disk_entry = disk_find_by_index(entry->index);
297 			if (disk_entry == NULL) {
298 				disk_entry = disk_entry_create(entry);
299 				if (disk_entry == NULL)
300 					continue;
301 
302 				disk_entry->access = DS_READ_WRITE;
303 				strlcpy(disk_entry->dev_name, entry->name,
304 				    sizeof(disk_entry->dev_name));
305 
306 				disk_entry->media = found->media;
307 				disk_entry->removable = found->removable;
308 			}
309 
310 			disk_entry->flags |= HR_DISKSTORAGE_FOUND;
311 			disk_entry->flags |= HR_DISKSTORAGE_ATA;
312 
313 			disk_query_disk(disk_entry);
314 			disk_entry->r_tick = this_tick;
315 		}
316 	}
317 }
318 
319 /**
320  * Find MD disks in the device table.
321  */
322 static void
323 disk_OS_get_MD_disks(void)
324 {
325 	struct device_map_entry *map;
326 	struct device_entry *entry;
327 	struct disk_entry *disk_entry;
328 	struct md_ioctl mdio;
329 	int unit;
330 
331 	/* Look for md devices */
332 	STAILQ_FOREACH(map, &device_map, link) {
333 		if (sscanf(map->name_key, "md%d", &unit) != 1)
334 			continue;
335 
336 		/* First get the entry from the hrDeviceTbl */
337 		entry = device_find_by_index(map->hrIndex);
338 		entry->type = OIDX_hrDeviceDiskStorage_c;
339 
340 		/* Then check hrDiskStorage table for this device */
341 		disk_entry = disk_find_by_index(entry->index);
342 		if (disk_entry == NULL) {
343 			disk_entry = disk_entry_create(entry);
344 			if (disk_entry == NULL)
345 				continue;
346 
347 			memset(&mdio, 0, sizeof(mdio));
348 			mdio.md_version = MDIOVERSION;
349 			mdio.md_unit = unit;
350 
351 			if (ioctl(md_fd, MDIOCQUERY, &mdio) < 0) {
352 				syslog(LOG_ERR,
353 				    "hrDiskStorageTable: Couldnt ioctl");
354 				continue;
355 			}
356 
357 			if ((mdio.md_options & MD_READONLY) == MD_READONLY)
358 				disk_entry->access = DS_READ_ONLY;
359 			else
360 				disk_entry->access = DS_READ_WRITE;
361 
362 			strlcpy(disk_entry->dev_name, entry->name,
363 			    sizeof(disk_entry->dev_name));
364 
365 			disk_entry->media = DSM_RAMDISK;
366 			disk_entry->removable = SNMP_FALSE;
367 		}
368 
369 		disk_entry->flags |= HR_DISKSTORAGE_FOUND;
370 		disk_entry->flags |= HR_DISKSTORAGE_MD;
371 		disk_entry->r_tick = this_tick;
372 	}
373 }
374 
375 /**
376  * Find rest of disks
377  */
378 static void
379 disk_OS_get_disks(void)
380 {
381 	size_t disk_cnt = 0;
382 	struct device_entry *entry;
383 	struct disk_entry *disk_entry;
384 
385 	size_t need = 0;
386 
387 	if (sysctlbyname("kern.disks", NULL, &need, NULL, 0) == -1) {
388 		syslog(LOG_ERR, "%s: sysctl_1 kern.disks failed: %m", __func__);
389 		return;
390 	}
391 
392 	if (need == 0)
393 		return;
394 
395 	if (disk_list_len != need + 1 || disk_list == NULL) {
396 		disk_list_len = need + 1;
397 		disk_list = reallocf(disk_list, disk_list_len);
398 	}
399 
400 	if (disk_list == NULL) {
401 		syslog(LOG_ERR, "%s: reallocf failed", __func__);
402 		disk_list_len = 0;
403 		return;
404 	}
405 
406 	memset(disk_list, 0, disk_list_len);
407 
408 	if (sysctlbyname("kern.disks", disk_list, &need, NULL, 0) == -1 ||
409 	    disk_list[0] == 0) {
410 		syslog(LOG_ERR, "%s: sysctl_2 kern.disks failed: %m", __func__);
411 		return;
412 	}
413 
414 	for (disk_cnt = 0; disk_cnt < need; disk_cnt++) {
415 		char *disk = NULL;
416 		char disk_device[128] = "";
417 
418 		disk = strsep(&disk_list, " ");
419 		if (disk == NULL)
420 			break;
421 
422 		snprintf(disk_device, sizeof(disk_device),
423 		    "%s%s", _PATH_DEV, disk);
424 
425 		/* First check if the disk is in the hrDeviceTable. */
426 		if ((entry = device_find_by_name(disk)) == NULL) {
427 			/*
428 			 * not found there - insert it as immutable
429 			 * XXX somehow we should remove it if it disappears
430 			 */
431 			syslog(LOG_WARNING, "%s: device '%s' not in "
432 			    "device list", __func__, disk);
433 
434 			if ((entry = device_entry_create(disk, "", "")) == NULL)
435 				continue;
436 
437 			entry->flags |= HR_DEVICE_IMMUTABLE;
438 		}
439 
440  		entry->type = OIDX_hrDeviceDiskStorage_c;
441 
442 		/* Then check hrDiskStorage table for this device */
443 		disk_entry = disk_find_by_index(entry->index);
444 		if (disk_entry == NULL) {
445 			disk_entry = disk_entry_create(entry);
446 			if (disk_entry == NULL)
447 				continue;
448 		}
449 
450 		disk_entry->flags |= HR_DISKSTORAGE_FOUND;
451 
452 		if ((disk_entry->flags & HR_DISKSTORAGE_ATA) ||
453 		    (disk_entry->flags & HR_DISKSTORAGE_MD)) {
454 			/*
455 			 * ATA/MD detection is running before this one,
456 			 * so don't waste the time here
457 			 */
458 			continue;
459 		}
460 
461 		disk_entry->access = DS_READ_WRITE;
462 		disk_entry->media = DSM_UNKNOWN;
463 		disk_entry->removable = SNMP_FALSE;
464 
465 		if (strncmp(disk_entry->dev_name, "da", 2) == 0) {
466 			disk_entry->media = DSM_HARDDISK;
467 			disk_entry->removable = SNMP_FALSE;
468 		} else if (strncmp(disk_entry->dev_name, "cd", 2) == 0) {
469 			disk_entry->media = DSM_OPTICALDISKROM;
470 			disk_entry->removable = SNMP_TRUE;
471 	 	} else {
472 			disk_entry->media = DSM_UNKNOWN;
473 			disk_entry->removable = SNMP_FALSE;
474 		}
475 
476 		strlcpy((char *)disk_entry->dev_name, disk,
477 		    sizeof(disk_entry->dev_name));
478 
479 		disk_query_disk(disk_entry);
480 		disk_entry->r_tick = this_tick;
481 	}
482 }
483 
484 /**
485  * Refresh routine for hrDiskStorageTable
486  * Usable for polling the system for any changes.
487  */
488 void
489 refresh_disk_storage_tbl(int force)
490 {
491 	struct disk_entry *entry, *entry_tmp;
492 
493 	if (disk_storage_tick != 0 && !force &&
494 	    this_tick - disk_storage_tick < disk_storage_tbl_refresh) {
495 		HRDBG("no refresh needed");
496 		return;
497 	}
498 
499 	partition_tbl_pre_refresh();
500 
501 	/* mark each entry as missing */
502 	TAILQ_FOREACH(entry, &disk_tbl, link)
503 		entry->flags &= ~HR_DISKSTORAGE_FOUND;
504 
505 	disk_OS_get_ATA_disks();	/* this must be called first ! */
506 	disk_OS_get_MD_disks();
507 	disk_OS_get_disks();
508 
509 	/*
510 	 * Purge items that disappeared
511 	 */
512 	TAILQ_FOREACH_SAFE(entry, &disk_tbl, link, entry_tmp)
513 		if (!(entry->flags & HR_DISKSTORAGE_FOUND))
514 			/* XXX remove IMMUTABLE entries that have disappeared */
515 			disk_entry_delete(entry);
516 
517 	disk_storage_tick = this_tick;
518 
519 	partition_tbl_post_refresh();
520 
521 	HRDBG("refresh DONE");
522 }
523 
524 /*
525  * Init the things for both of hrDiskStorageTable
526  */
527 int
528 init_disk_storage_tbl(void)
529 {
530 	char mddev[32] = "";
531 
532 	/* Try to load md.ko if not loaded already */
533 	mdmaybeload();
534 
535 	md_fd = -1;
536 	snprintf(mddev, sizeof(mddev) - 1, "%s%s", _PATH_DEV, MDCTL_NAME);
537 	if ((md_fd = open(mddev, O_RDWR)) == -1) {
538 		syslog(LOG_ERR, "open %s failed: %m", mddev);
539 		return (-1);
540 	}
541 
542 	refresh_disk_storage_tbl(1);
543 
544 	return (0);
545 }
546 
547 /*
548  * Finalization routine for hrDiskStorageTable
549  * It destroys the lists and frees any allocated heap memory
550  */
551 void
552 fini_disk_storage_tbl(void)
553 {
554 	struct disk_entry *n1;
555 
556 	while ((n1 = TAILQ_FIRST(&disk_tbl)) != NULL) {
557 		TAILQ_REMOVE(&disk_tbl, n1, link);
558 		free(n1);
559 	}
560 
561 	free(disk_list);
562 
563 	if (md_fd > 0) {
564 		if (close(md_fd) == -1)
565 			syslog(LOG_ERR,"close (/dev/mdctl) failed: %m");
566 		md_fd = -1;
567 	}
568 }
569 
570 /*
571  * This is the implementation for a generated (by our SNMP "compiler" tool)
572  * function prototype, see hostres_tree.h
573  * It handles the SNMP operations for hrDiskStorageTable
574  */
575 int
576 op_hrDiskStorageTable(struct snmp_context *ctx __unused,
577     struct snmp_value *value, u_int sub, u_int iidx __unused,
578     enum snmp_op curr_op)
579 {
580 	struct disk_entry *entry;
581 
582 	refresh_disk_storage_tbl(0);
583 
584 	switch (curr_op) {
585 
586 	case SNMP_OP_GETNEXT:
587 		if ((entry = NEXT_OBJECT_INT(&disk_tbl,
588 		    &value->var, sub)) == NULL)
589 			return (SNMP_ERR_NOSUCHNAME);
590 		value->var.len = sub + 1;
591 		value->var.subs[sub] = entry->index;
592 		goto get;
593 
594 	case SNMP_OP_GET:
595 		if ((entry = FIND_OBJECT_INT(&disk_tbl,
596 		    &value->var, sub)) == NULL)
597 			return (SNMP_ERR_NOSUCHNAME);
598 		goto get;
599 
600 	case SNMP_OP_SET:
601 		if ((entry = FIND_OBJECT_INT(&disk_tbl,
602 		    &value->var, sub)) == NULL)
603 			return (SNMP_ERR_NO_CREATION);
604 		return (SNMP_ERR_NOT_WRITEABLE);
605 
606 	case SNMP_OP_ROLLBACK:
607 	case SNMP_OP_COMMIT:
608 	  	abort();
609 	}
610 	abort();
611 
612   get:
613 	switch (value->var.subs[sub - 1]) {
614 
615 	case LEAF_hrDiskStorageAccess:
616 	  	value->v.integer = entry->access;
617 	  	return (SNMP_ERR_NOERROR);
618 
619 	case LEAF_hrDiskStorageMedia:
620 	  	value->v.integer = entry->media;
621 	  	return (SNMP_ERR_NOERROR);
622 
623 	case LEAF_hrDiskStorageRemoveble:
624 	  	value->v.integer = entry->removable;
625 	  	return (SNMP_ERR_NOERROR);
626 
627 	case LEAF_hrDiskStorageCapacity:
628 	  	value->v.integer = entry->capacity;
629 	  	return (SNMP_ERR_NOERROR);
630 	}
631 	abort();
632 }
633