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 hrFSTable
34 */
35
36 #include <sys/types.h>
37 #include <sys/param.h>
38 #include <sys/sysctl.h>
39 #include <sys/mount.h>
40
41 #include <assert.h>
42 #include <err.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <syslog.h>
46 #include <sysexits.h>
47
48 #include "hostres_snmp.h"
49 #include "hostres_oid.h"
50 #include "hostres_tree.h"
51
52 /*
53 * File system access enum
54 */
55 enum hrFSAccess {
56 FS_READ_WRITE = 1,
57 FS_READ_ONLY = 2
58 };
59
60 /* maximum length (according to MIB) for fs_entry::mountPoint */
61 #define FS_MP_MLEN (128 + 1)
62
63 /* maximum length (according to MIB) for fs_entry::remoteMountPoint */
64 #define FS_RMP_MLEN (128 + 1)
65
66 /*
67 * This structure is used to hold a SNMP table entry
68 * for HOST-RESOURCES-MIB's hrFSTable
69 */
70 struct fs_entry {
71 int32_t index;
72 u_char *mountPoint;
73 u_char *remoteMountPoint;
74 const struct asn_oid *type;
75 int32_t access; /* enum hrFSAccess, see above */
76 int32_t bootable; /* TruthValue */
77 int32_t storageIndex; /* hrStorageTblEntry::index */
78 u_char lastFullBackupDate[11];
79 u_char lastPartialBackupDate[11];
80 #define HR_FS_FOUND 0x001
81 uint32_t flags; /* not in mib table, for internal use */
82 TAILQ_ENTRY(fs_entry) link;
83 };
84 TAILQ_HEAD(fs_tbl, fs_entry);
85
86 /*
87 * Next structure is used to keep o list of mappings from a specific name
88 * (a_name) to an entry in the hrFSTblEntry. We are trying to keep the same
89 * index for a specific name at least for the duration of one SNMP agent run.
90 */
91 struct fs_map_entry {
92 int32_t hrIndex; /* used for fs_entry::index */
93 u_char *a_name; /* map key same as fs_entry::mountPoint */
94
95 /* may be NULL if the respective hrFSTblEntry is (temporally) gone */
96 struct fs_entry *entry;
97 STAILQ_ENTRY(fs_map_entry) link;
98 };
99 STAILQ_HEAD(fs_map, fs_map_entry);
100
101 /* head of the list with hrFSTable's entries */
102 static struct fs_tbl fs_tbl = TAILQ_HEAD_INITIALIZER(fs_tbl);
103
104 /* for consistent table indexing */
105 static struct fs_map fs_map = STAILQ_HEAD_INITIALIZER(fs_map);
106
107 /* next index available for hrFSTable */
108 static uint32_t next_fs_index = 1;
109
110 /* last tick when hrFSTable was updated */
111 static uint64_t fs_tick;
112
113 /* maximum number of ticks between refreshs */
114 uint32_t fs_tbl_refresh = HR_FS_TBL_REFRESH * 100;
115
116 /* some constants */
117 static const struct asn_oid OIDX_hrFSBerkeleyFFS_c = OIDX_hrFSBerkeleyFFS;
118 static const struct asn_oid OIDX_hrFSiso9660_c = OIDX_hrFSiso9660;
119 static const struct asn_oid OIDX_hrFSNFS_c = OIDX_hrFSNFS;
120 static const struct asn_oid OIDX_hrFSLinuxExt2_c = OIDX_hrFSLinuxExt2;
121 static const struct asn_oid OIDX_hrFSOther_c = OIDX_hrFSOther;
122 static const struct asn_oid OIDX_hrFSFAT32_c = OIDX_hrFSFAT32;
123 static const struct asn_oid OIDX_hrFSNTFS_c = OIDX_hrFSNTFS;
124 static const struct asn_oid OIDX_hrFSNetware_c = OIDX_hrFSNetware;
125 static const struct asn_oid OIDX_hrFSHPFS_c = OIDX_hrFSHPFS;
126 static const struct asn_oid OIDX_hrFSUnknown_c = OIDX_hrFSUnknown;
127
128 /* file system type map */
129 static const struct {
130 const char *str; /* the type string */
131 const struct asn_oid *oid; /* the OID to return */
132 } fs_type_map[] = {
133 { "ufs", &OIDX_hrFSBerkeleyFFS_c },
134 { "zfs", &OIDX_hrFSOther_c },
135 { "cd9660", &OIDX_hrFSiso9660_c },
136 { "nfs", &OIDX_hrFSNFS_c },
137 { "ext2fs", &OIDX_hrFSLinuxExt2_c },
138 { "procfs", &OIDX_hrFSOther_c },
139 { "devfs", &OIDX_hrFSOther_c },
140 { "msdosfs", &OIDX_hrFSFAT32_c },
141 { "ntfs", &OIDX_hrFSNTFS_c },
142 { "nwfs", &OIDX_hrFSNetware_c },
143 { "hpfs", &OIDX_hrFSHPFS_c },
144 { "smbfs", &OIDX_hrFSOther_c },
145 };
146 #define N_FS_TYPE_MAP (sizeof(fs_type_map) / sizeof(fs_type_map[0]))
147
148 /**
149 * Create an entry into the FS table and an entry in the map (if needed).
150 */
151 static struct fs_entry *
fs_entry_create(const char * name)152 fs_entry_create(const char *name)
153 {
154 struct fs_entry *entry;
155 struct fs_map_entry *map;
156
157 assert(name != NULL);
158 assert(strlen(name) > 0);
159
160 STAILQ_FOREACH(map, &fs_map, link)
161 if (strcmp(map->a_name, name) == 0)
162 break;
163
164 if (map == NULL) {
165 size_t mount_point_len;
166
167 /* new object - get a new index */
168 if (next_fs_index > INT_MAX) {
169 /* Unrecoverable error - die clean and quicly*/
170 syslog(LOG_ERR, "%s: hrFSTable index wrap", __func__);
171 errx(EX_SOFTWARE, "hrFSTable index wrap");
172 }
173
174 if ((map = malloc(sizeof(*map))) == NULL) {
175 syslog(LOG_ERR, "%s: %m", __func__);
176 return (NULL);
177 }
178
179 mount_point_len = strlen(name) + 1;
180 if (mount_point_len > FS_MP_MLEN)
181 mount_point_len = FS_MP_MLEN;
182
183 if ((map->a_name = malloc(mount_point_len)) == NULL) {
184 syslog(LOG_ERR, "%s: %m", __func__);
185 free(map);
186 return (NULL);
187 }
188
189 strlcpy(map->a_name, name, mount_point_len);
190
191 map->hrIndex = next_fs_index++;
192 map->entry = NULL;
193 STAILQ_INSERT_TAIL(&fs_map, map, link);
194
195 HRDBG("%s added into hrFSMap at index=%d", name, map->hrIndex);
196 } else {
197 HRDBG("%s exists in hrFSMap index=%d", name, map->hrIndex);
198 }
199
200 if ((entry = malloc(sizeof(*entry))) == NULL) {
201 syslog(LOG_WARNING, "%s: %m", __func__);
202 return (NULL);
203 }
204
205 if ((entry->mountPoint = strdup(name)) == NULL) {
206 syslog(LOG_ERR, "%s: %m", __func__);
207 free(entry);
208 return (NULL);
209 }
210
211 entry->index = map->hrIndex;
212 map->entry = entry;
213
214 INSERT_OBJECT_INT(entry, &fs_tbl);
215 return (entry);
216 }
217
218 /**
219 * Delete an entry in the FS table.
220 */
221 static void
fs_entry_delete(struct fs_entry * entry)222 fs_entry_delete(struct fs_entry* entry)
223 {
224 struct fs_map_entry *map;
225
226 assert(entry != NULL);
227
228 TAILQ_REMOVE(&fs_tbl, entry, link);
229 STAILQ_FOREACH(map, &fs_map, link)
230 if (map->entry == entry) {
231 map->entry = NULL;
232 break;
233 }
234 free(entry->mountPoint);
235 free(entry->remoteMountPoint);
236 free(entry);
237 }
238
239 /**
240 * Find a table entry by its name
241 */
242 static struct fs_entry *
fs_find_by_name(const char * name)243 fs_find_by_name(const char *name)
244 {
245 struct fs_entry *entry;
246
247 TAILQ_FOREACH(entry, &fs_tbl, link)
248 if (strcmp(entry->mountPoint, name) == 0)
249 return (entry);
250
251 return (NULL);
252 }
253
254 /**
255 * Get rid of all data
256 */
257 void
fini_fs_tbl(void)258 fini_fs_tbl(void)
259 {
260 struct fs_map_entry *n1;
261
262 while ((n1 = STAILQ_FIRST(&fs_map)) != NULL) {
263 STAILQ_REMOVE_HEAD(&fs_map, link);
264 if (n1->entry != NULL) {
265 TAILQ_REMOVE(&fs_tbl, n1->entry, link);
266 free(n1->entry->mountPoint);
267 free(n1->entry->remoteMountPoint);
268 free(n1->entry);
269 }
270 free(n1->a_name);
271 free(n1);
272 }
273 assert(TAILQ_EMPTY(&fs_tbl));
274 }
275
276 /**
277 * Called before the refreshing is started from the storage table.
278 */
279 void
fs_tbl_pre_refresh(void)280 fs_tbl_pre_refresh(void)
281 {
282 struct fs_entry *entry;
283
284 /* mark each entry as missisng */
285 TAILQ_FOREACH(entry, &fs_tbl, link)
286 entry->flags &= ~HR_FS_FOUND;
287 }
288
289 /**
290 * Called after refreshing from the storage table.
291 */
292 void
fs_tbl_post_refresh(void)293 fs_tbl_post_refresh(void)
294 {
295 struct fs_entry *entry, *entry_tmp;
296
297 /*
298 * Purge items that disappeared
299 */
300 TAILQ_FOREACH_SAFE(entry, &fs_tbl, link, entry_tmp)
301 if (!(entry->flags & HR_FS_FOUND))
302 fs_entry_delete(entry);
303
304 fs_tick = this_tick;
305 }
306
307 /*
308 * Refresh the FS table. This is done by forcing a refresh of the storage table.
309 */
310 void
refresh_fs_tbl(void)311 refresh_fs_tbl(void)
312 {
313
314 if (fs_tick == 0 || this_tick - fs_tick >= fs_tbl_refresh) {
315 refresh_storage_tbl(1);
316 HRDBG("refresh DONE");
317 }
318 }
319
320 /**
321 * Get the type OID for a given file system
322 */
323 const struct asn_oid *
fs_get_type(const struct statfs * fs_p)324 fs_get_type(const struct statfs *fs_p)
325 {
326 u_int t;
327
328 assert(fs_p != NULL);
329
330 for (t = 0; t < N_FS_TYPE_MAP; t++)
331 if (strcmp(fs_type_map[t].str, fs_p->f_fstypename) == 0)
332 return (fs_type_map[t].oid);
333
334 return (&OIDX_hrFSUnknown_c);
335 }
336
337 /*
338 * Given information returned from statfs(2) either create a new entry into
339 * the fs_tbl or refresh the entry if it is already there.
340 */
341 void
fs_tbl_process_statfs_entry(const struct statfs * fs_p,int32_t storage_idx)342 fs_tbl_process_statfs_entry(const struct statfs *fs_p, int32_t storage_idx)
343 {
344 struct fs_entry *entry;
345
346 assert(fs_p != 0);
347
348 HRDBG("for hrStorageEntry::index %d", storage_idx);
349
350 if (fs_p == NULL)
351 return;
352
353 if ((entry = fs_find_by_name(fs_p->f_mntonname)) != NULL ||
354 (entry = fs_entry_create(fs_p->f_mntonname)) != NULL) {
355 entry->flags |= HR_FS_FOUND;
356
357 if (!(fs_p->f_flags & MNT_LOCAL)) {
358 /* this is a remote mount */
359 entry->remoteMountPoint = strdup(fs_p->f_mntfromname);
360 /* if strdup failed, let it be NULL */
361
362 } else {
363 entry->remoteMountPoint = strdup("");
364 /* if strdup failed, let it be NULL */
365 }
366
367 entry->type = fs_get_type(fs_p);
368
369 if ((fs_p->f_flags & MNT_RDONLY) == MNT_RDONLY)
370 entry->access = FS_READ_ONLY;
371 else
372 entry->access = FS_READ_WRITE;
373
374 /* FIXME - bootable fs ?! */
375 entry->bootable = TRUTH_MK((fs_p->f_flags & MNT_ROOTFS)
376 == MNT_ROOTFS);
377
378 entry->storageIndex = storage_idx;
379
380 /* Info not available */
381 memset(entry->lastFullBackupDate, 0,
382 sizeof(entry->lastFullBackupDate));
383
384 /* Info not available */
385 memset(entry->lastPartialBackupDate, 0,
386 sizeof(entry->lastPartialBackupDate));
387
388 handle_partition_fs_index(fs_p->f_mntfromname, entry->index);
389 }
390 }
391
392 /*
393 * This is the implementation for a generated (by our SNMP "compiler" tool)
394 * function prototype, see hostres_tree.h
395 * It handles the SNMP operations for hrFSTable
396 */
397 int
op_hrFSTable(struct snmp_context * ctx __unused,struct snmp_value * value,u_int sub,u_int iidx __unused,enum snmp_op curr_op)398 op_hrFSTable(struct snmp_context *ctx __unused, struct snmp_value *value,
399 u_int sub, u_int iidx __unused, enum snmp_op curr_op)
400 {
401 struct fs_entry *entry;
402
403 refresh_fs_tbl();
404
405 switch (curr_op) {
406
407 case SNMP_OP_GETNEXT:
408 if ((entry = NEXT_OBJECT_INT(&fs_tbl,
409 &value->var, sub)) == NULL)
410 return (SNMP_ERR_NOSUCHNAME);
411 value->var.len = sub + 1;
412 value->var.subs[sub] = entry->index;
413 goto get;
414
415 case SNMP_OP_GET:
416 if ((entry = FIND_OBJECT_INT(&fs_tbl,
417 &value->var, sub)) == NULL)
418 return (SNMP_ERR_NOSUCHNAME);
419 goto get;
420
421 case SNMP_OP_SET:
422 if ((entry = FIND_OBJECT_INT(&fs_tbl,
423 &value->var, sub)) == NULL)
424 return (SNMP_ERR_NO_CREATION);
425 return (SNMP_ERR_NOT_WRITEABLE);
426
427 case SNMP_OP_ROLLBACK:
428 case SNMP_OP_COMMIT:
429 abort();
430 }
431 abort();
432 get:
433 switch (value->var.subs[sub - 1]) {
434
435 case LEAF_hrFSIndex:
436 value->v.integer = entry->index;
437 return (SNMP_ERR_NOERROR);
438
439 case LEAF_hrFSMountPoint:
440 return (string_get(value, entry->mountPoint, -1));
441
442 case LEAF_hrFSRemoteMountPoint:
443 if (entry->remoteMountPoint == NULL)
444 return (string_get(value, "", -1));
445 else
446 return (string_get(value, entry->remoteMountPoint, -1));
447 break;
448
449 case LEAF_hrFSType:
450 assert(entry->type != NULL);
451 value->v.oid = *(entry->type);
452 return (SNMP_ERR_NOERROR);
453
454 case LEAF_hrFSAccess:
455 value->v.integer = entry->access;
456 return (SNMP_ERR_NOERROR);
457
458 case LEAF_hrFSBootable:
459 value->v.integer = entry->bootable;
460 return (SNMP_ERR_NOERROR);
461
462 case LEAF_hrFSStorageIndex:
463 value->v.integer = entry->storageIndex;
464 return (SNMP_ERR_NOERROR);
465
466 case LEAF_hrFSLastFullBackupDate:
467 return (string_get(value, entry->lastFullBackupDate, 8));
468
469 case LEAF_hrFSLastPartialBackupDate:
470 return (string_get(value, entry->lastPartialBackupDate, 8));
471 }
472 abort();
473 }
474