Commit | Line | Data |
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446fda4f PM |
1 | /* |
2 | * CIPSO - Commercial IP Security Option | |
3 | * | |
4 | * This is an implementation of the CIPSO 2.2 protocol as specified in | |
5 | * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in | |
6 | * FIPS-188, copies of both documents can be found in the Documentation | |
7 | * directory. While CIPSO never became a full IETF RFC standard many vendors | |
8 | * have chosen to adopt the protocol and over the years it has become a | |
9 | * de-facto standard for labeled networking. | |
10 | * | |
11 | * Author: Paul Moore <paul.moore@hp.com> | |
12 | * | |
13 | */ | |
14 | ||
15 | /* | |
16 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 | |
17 | * | |
18 | * This program is free software; you can redistribute it and/or modify | |
19 | * it under the terms of the GNU General Public License as published by | |
20 | * the Free Software Foundation; either version 2 of the License, or | |
21 | * (at your option) any later version. | |
22 | * | |
23 | * This program is distributed in the hope that it will be useful, | |
24 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
25 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
26 | * the GNU General Public License for more details. | |
27 | * | |
28 | * You should have received a copy of the GNU General Public License | |
29 | * along with this program; if not, write to the Free Software | |
30 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
31 | * | |
32 | */ | |
33 | ||
34 | #include <linux/init.h> | |
35 | #include <linux/types.h> | |
36 | #include <linux/rcupdate.h> | |
37 | #include <linux/list.h> | |
38 | #include <linux/spinlock.h> | |
39 | #include <linux/string.h> | |
40 | #include <linux/jhash.h> | |
41 | #include <net/ip.h> | |
42 | #include <net/icmp.h> | |
43 | #include <net/tcp.h> | |
44 | #include <net/netlabel.h> | |
45 | #include <net/cipso_ipv4.h> | |
ffb733c6 | 46 | #include <asm/atomic.h> |
446fda4f PM |
47 | #include <asm/bug.h> |
48 | ||
49 | struct cipso_v4_domhsh_entry { | |
50 | char *domain; | |
51 | u32 valid; | |
52 | struct list_head list; | |
53 | struct rcu_head rcu; | |
54 | }; | |
55 | ||
56 | /* List of available DOI definitions */ | |
57 | /* XXX - Updates should be minimal so having a single lock for the | |
58 | * cipso_v4_doi_list and the cipso_v4_doi_list->dom_list should be | |
59 | * okay. */ | |
60 | /* XXX - This currently assumes a minimal number of different DOIs in use, | |
61 | * if in practice there are a lot of different DOIs this list should | |
62 | * probably be turned into a hash table or something similar so we | |
63 | * can do quick lookups. */ | |
8ce11e6a | 64 | static DEFINE_SPINLOCK(cipso_v4_doi_list_lock); |
446fda4f PM |
65 | static struct list_head cipso_v4_doi_list = LIST_HEAD_INIT(cipso_v4_doi_list); |
66 | ||
67 | /* Label mapping cache */ | |
68 | int cipso_v4_cache_enabled = 1; | |
69 | int cipso_v4_cache_bucketsize = 10; | |
70 | #define CIPSO_V4_CACHE_BUCKETBITS 7 | |
71 | #define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS) | |
72 | #define CIPSO_V4_CACHE_REORDERLIMIT 10 | |
73 | struct cipso_v4_map_cache_bkt { | |
74 | spinlock_t lock; | |
75 | u32 size; | |
76 | struct list_head list; | |
77 | }; | |
78 | struct cipso_v4_map_cache_entry { | |
79 | u32 hash; | |
80 | unsigned char *key; | |
81 | size_t key_len; | |
82 | ||
ffb733c6 | 83 | struct netlbl_lsm_cache *lsm_data; |
446fda4f PM |
84 | |
85 | u32 activity; | |
86 | struct list_head list; | |
87 | }; | |
88 | static struct cipso_v4_map_cache_bkt *cipso_v4_cache = NULL; | |
89 | ||
90 | /* Restricted bitmap (tag #1) flags */ | |
91 | int cipso_v4_rbm_optfmt = 0; | |
92 | int cipso_v4_rbm_strictvalid = 1; | |
93 | ||
f998e8cb PM |
94 | /* |
95 | * Protocol Constants | |
96 | */ | |
97 | ||
98 | /* Maximum size of the CIPSO IP option, derived from the fact that the maximum | |
99 | * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */ | |
100 | #define CIPSO_V4_OPT_LEN_MAX 40 | |
101 | ||
102 | /* Length of the base CIPSO option, this includes the option type (1 byte), the | |
103 | * option length (1 byte), and the DOI (4 bytes). */ | |
104 | #define CIPSO_V4_HDR_LEN 6 | |
105 | ||
106 | /* Base length of the restrictive category bitmap tag (tag #1). */ | |
107 | #define CIPSO_V4_TAG_RBM_BLEN 4 | |
108 | ||
109 | /* Base length of the enumerated category tag (tag #2). */ | |
110 | #define CIPSO_V4_TAG_ENUM_BLEN 4 | |
111 | ||
112 | /* Base length of the ranged categories bitmap tag (tag #5). */ | |
113 | #define CIPSO_V4_TAG_RNG_BLEN 4 | |
114 | /* The maximum number of category ranges permitted in the ranged category tag | |
115 | * (tag #5). You may note that the IETF draft states that the maximum number | |
116 | * of category ranges is 7, but if the low end of the last category range is | |
117 | * zero then it is possibile to fit 8 category ranges because the zero should | |
118 | * be omitted. */ | |
119 | #define CIPSO_V4_TAG_RNG_CAT_MAX 8 | |
120 | ||
446fda4f PM |
121 | /* |
122 | * Helper Functions | |
123 | */ | |
124 | ||
125 | /** | |
126 | * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit | |
127 | * @bitmap: the bitmap | |
128 | * @bitmap_len: length in bits | |
129 | * @offset: starting offset | |
130 | * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit | |
131 | * | |
132 | * Description: | |
133 | * Starting at @offset, walk the bitmap from left to right until either the | |
134 | * desired bit is found or we reach the end. Return the bit offset, -1 if | |
135 | * not found, or -2 if error. | |
136 | */ | |
137 | static int cipso_v4_bitmap_walk(const unsigned char *bitmap, | |
138 | u32 bitmap_len, | |
139 | u32 offset, | |
140 | u8 state) | |
141 | { | |
142 | u32 bit_spot; | |
143 | u32 byte_offset; | |
144 | unsigned char bitmask; | |
145 | unsigned char byte; | |
146 | ||
147 | /* gcc always rounds to zero when doing integer division */ | |
148 | byte_offset = offset / 8; | |
149 | byte = bitmap[byte_offset]; | |
150 | bit_spot = offset; | |
151 | bitmask = 0x80 >> (offset % 8); | |
152 | ||
153 | while (bit_spot < bitmap_len) { | |
154 | if ((state && (byte & bitmask) == bitmask) || | |
155 | (state == 0 && (byte & bitmask) == 0)) | |
156 | return bit_spot; | |
157 | ||
158 | bit_spot++; | |
159 | bitmask >>= 1; | |
160 | if (bitmask == 0) { | |
161 | byte = bitmap[++byte_offset]; | |
162 | bitmask = 0x80; | |
163 | } | |
164 | } | |
165 | ||
166 | return -1; | |
167 | } | |
168 | ||
169 | /** | |
170 | * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap | |
171 | * @bitmap: the bitmap | |
172 | * @bit: the bit | |
173 | * @state: if non-zero, set the bit (1) else clear the bit (0) | |
174 | * | |
175 | * Description: | |
176 | * Set a single bit in the bitmask. Returns zero on success, negative values | |
177 | * on error. | |
178 | */ | |
179 | static void cipso_v4_bitmap_setbit(unsigned char *bitmap, | |
180 | u32 bit, | |
181 | u8 state) | |
182 | { | |
183 | u32 byte_spot; | |
184 | u8 bitmask; | |
185 | ||
186 | /* gcc always rounds to zero when doing integer division */ | |
187 | byte_spot = bit / 8; | |
188 | bitmask = 0x80 >> (bit % 8); | |
189 | if (state) | |
190 | bitmap[byte_spot] |= bitmask; | |
191 | else | |
192 | bitmap[byte_spot] &= ~bitmask; | |
193 | } | |
194 | ||
195 | /** | |
196 | * cipso_v4_doi_domhsh_free - Frees a domain list entry | |
197 | * @entry: the entry's RCU field | |
198 | * | |
199 | * Description: | |
200 | * This function is designed to be used as a callback to the call_rcu() | |
201 | * function so that the memory allocated to a domain list entry can be released | |
202 | * safely. | |
203 | * | |
204 | */ | |
205 | static void cipso_v4_doi_domhsh_free(struct rcu_head *entry) | |
206 | { | |
207 | struct cipso_v4_domhsh_entry *ptr; | |
208 | ||
209 | ptr = container_of(entry, struct cipso_v4_domhsh_entry, rcu); | |
210 | kfree(ptr->domain); | |
211 | kfree(ptr); | |
212 | } | |
213 | ||
214 | /** | |
215 | * cipso_v4_cache_entry_free - Frees a cache entry | |
216 | * @entry: the entry to free | |
217 | * | |
218 | * Description: | |
ffb733c6 | 219 | * This function frees the memory associated with a cache entry including the |
220 | * LSM cache data if there are no longer any users, i.e. reference count == 0. | |
446fda4f PM |
221 | * |
222 | */ | |
223 | static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) | |
224 | { | |
ffb733c6 | 225 | if (entry->lsm_data) |
226 | netlbl_secattr_cache_free(entry->lsm_data); | |
446fda4f PM |
227 | kfree(entry->key); |
228 | kfree(entry); | |
229 | } | |
230 | ||
231 | /** | |
232 | * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache | |
233 | * @key: the hash key | |
234 | * @key_len: the length of the key in bytes | |
235 | * | |
236 | * Description: | |
237 | * The CIPSO tag hashing function. Returns a 32-bit hash value. | |
238 | * | |
239 | */ | |
240 | static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) | |
241 | { | |
242 | return jhash(key, key_len, 0); | |
243 | } | |
244 | ||
245 | /* | |
246 | * Label Mapping Cache Functions | |
247 | */ | |
248 | ||
249 | /** | |
250 | * cipso_v4_cache_init - Initialize the CIPSO cache | |
251 | * | |
252 | * Description: | |
253 | * Initializes the CIPSO label mapping cache, this function should be called | |
254 | * before any of the other functions defined in this file. Returns zero on | |
255 | * success, negative values on error. | |
256 | * | |
257 | */ | |
258 | static int cipso_v4_cache_init(void) | |
259 | { | |
260 | u32 iter; | |
261 | ||
262 | cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS, | |
263 | sizeof(struct cipso_v4_map_cache_bkt), | |
264 | GFP_KERNEL); | |
265 | if (cipso_v4_cache == NULL) | |
266 | return -ENOMEM; | |
267 | ||
268 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
269 | spin_lock_init(&cipso_v4_cache[iter].lock); | |
270 | cipso_v4_cache[iter].size = 0; | |
271 | INIT_LIST_HEAD(&cipso_v4_cache[iter].list); | |
272 | } | |
273 | ||
274 | return 0; | |
275 | } | |
276 | ||
277 | /** | |
278 | * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache | |
279 | * | |
280 | * Description: | |
281 | * Invalidates and frees any entries in the CIPSO cache. Returns zero on | |
282 | * success and negative values on failure. | |
283 | * | |
284 | */ | |
285 | void cipso_v4_cache_invalidate(void) | |
286 | { | |
287 | struct cipso_v4_map_cache_entry *entry, *tmp_entry; | |
288 | u32 iter; | |
289 | ||
290 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
609c92fe | 291 | spin_lock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
292 | list_for_each_entry_safe(entry, |
293 | tmp_entry, | |
294 | &cipso_v4_cache[iter].list, list) { | |
295 | list_del(&entry->list); | |
296 | cipso_v4_cache_entry_free(entry); | |
297 | } | |
298 | cipso_v4_cache[iter].size = 0; | |
609c92fe | 299 | spin_unlock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
300 | } |
301 | ||
302 | return; | |
303 | } | |
304 | ||
305 | /** | |
306 | * cipso_v4_cache_check - Check the CIPSO cache for a label mapping | |
307 | * @key: the buffer to check | |
308 | * @key_len: buffer length in bytes | |
309 | * @secattr: the security attribute struct to use | |
310 | * | |
311 | * Description: | |
312 | * This function checks the cache to see if a label mapping already exists for | |
313 | * the given key. If there is a match then the cache is adjusted and the | |
314 | * @secattr struct is populated with the correct LSM security attributes. The | |
315 | * cache is adjusted in the following manner if the entry is not already the | |
316 | * first in the cache bucket: | |
317 | * | |
318 | * 1. The cache entry's activity counter is incremented | |
319 | * 2. The previous (higher ranking) entry's activity counter is decremented | |
320 | * 3. If the difference between the two activity counters is geater than | |
321 | * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped | |
322 | * | |
323 | * Returns zero on success, -ENOENT for a cache miss, and other negative values | |
324 | * on error. | |
325 | * | |
326 | */ | |
327 | static int cipso_v4_cache_check(const unsigned char *key, | |
328 | u32 key_len, | |
329 | struct netlbl_lsm_secattr *secattr) | |
330 | { | |
331 | u32 bkt; | |
332 | struct cipso_v4_map_cache_entry *entry; | |
333 | struct cipso_v4_map_cache_entry *prev_entry = NULL; | |
334 | u32 hash; | |
335 | ||
336 | if (!cipso_v4_cache_enabled) | |
337 | return -ENOENT; | |
338 | ||
339 | hash = cipso_v4_map_cache_hash(key, key_len); | |
340 | bkt = hash & (CIPSO_V4_CACHE_BUCKETBITS - 1); | |
609c92fe | 341 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
342 | list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) { |
343 | if (entry->hash == hash && | |
344 | entry->key_len == key_len && | |
345 | memcmp(entry->key, key, key_len) == 0) { | |
346 | entry->activity += 1; | |
ffb733c6 | 347 | atomic_inc(&entry->lsm_data->refcount); |
348 | secattr->cache = entry->lsm_data; | |
701a90ba | 349 | secattr->flags |= NETLBL_SECATTR_CACHE; |
446fda4f | 350 | if (prev_entry == NULL) { |
609c92fe | 351 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
352 | return 0; |
353 | } | |
354 | ||
355 | if (prev_entry->activity > 0) | |
356 | prev_entry->activity -= 1; | |
357 | if (entry->activity > prev_entry->activity && | |
358 | entry->activity - prev_entry->activity > | |
359 | CIPSO_V4_CACHE_REORDERLIMIT) { | |
360 | __list_del(entry->list.prev, entry->list.next); | |
361 | __list_add(&entry->list, | |
362 | prev_entry->list.prev, | |
363 | &prev_entry->list); | |
364 | } | |
365 | ||
609c92fe | 366 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
367 | return 0; |
368 | } | |
369 | prev_entry = entry; | |
370 | } | |
609c92fe | 371 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
372 | |
373 | return -ENOENT; | |
374 | } | |
375 | ||
376 | /** | |
377 | * cipso_v4_cache_add - Add an entry to the CIPSO cache | |
378 | * @skb: the packet | |
379 | * @secattr: the packet's security attributes | |
380 | * | |
381 | * Description: | |
382 | * Add a new entry into the CIPSO label mapping cache. Add the new entry to | |
383 | * head of the cache bucket's list, if the cache bucket is out of room remove | |
384 | * the last entry in the list first. It is important to note that there is | |
385 | * currently no checking for duplicate keys. Returns zero on success, | |
386 | * negative values on failure. | |
387 | * | |
388 | */ | |
389 | int cipso_v4_cache_add(const struct sk_buff *skb, | |
390 | const struct netlbl_lsm_secattr *secattr) | |
391 | { | |
392 | int ret_val = -EPERM; | |
393 | u32 bkt; | |
394 | struct cipso_v4_map_cache_entry *entry = NULL; | |
395 | struct cipso_v4_map_cache_entry *old_entry = NULL; | |
396 | unsigned char *cipso_ptr; | |
397 | u32 cipso_ptr_len; | |
398 | ||
399 | if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) | |
400 | return 0; | |
401 | ||
402 | cipso_ptr = CIPSO_V4_OPTPTR(skb); | |
403 | cipso_ptr_len = cipso_ptr[1]; | |
404 | ||
405 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); | |
406 | if (entry == NULL) | |
407 | return -ENOMEM; | |
fac5d731 | 408 | entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC); |
446fda4f PM |
409 | if (entry->key == NULL) { |
410 | ret_val = -ENOMEM; | |
411 | goto cache_add_failure; | |
412 | } | |
446fda4f PM |
413 | entry->key_len = cipso_ptr_len; |
414 | entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len); | |
ffb733c6 | 415 | atomic_inc(&secattr->cache->refcount); |
416 | entry->lsm_data = secattr->cache; | |
446fda4f PM |
417 | |
418 | bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETBITS - 1); | |
609c92fe | 419 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
420 | if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { |
421 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
422 | cipso_v4_cache[bkt].size += 1; | |
423 | } else { | |
424 | old_entry = list_entry(cipso_v4_cache[bkt].list.prev, | |
425 | struct cipso_v4_map_cache_entry, list); | |
426 | list_del(&old_entry->list); | |
427 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
428 | cipso_v4_cache_entry_free(old_entry); | |
429 | } | |
609c92fe | 430 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
431 | |
432 | return 0; | |
433 | ||
434 | cache_add_failure: | |
435 | if (entry) | |
436 | cipso_v4_cache_entry_free(entry); | |
437 | return ret_val; | |
438 | } | |
439 | ||
440 | /* | |
441 | * DOI List Functions | |
442 | */ | |
443 | ||
444 | /** | |
445 | * cipso_v4_doi_search - Searches for a DOI definition | |
446 | * @doi: the DOI to search for | |
447 | * | |
448 | * Description: | |
449 | * Search the DOI definition list for a DOI definition with a DOI value that | |
450 | * matches @doi. The caller is responsibile for calling rcu_read_[un]lock(). | |
451 | * Returns a pointer to the DOI definition on success and NULL on failure. | |
452 | */ | |
453 | static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) | |
454 | { | |
455 | struct cipso_v4_doi *iter; | |
456 | ||
457 | list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) | |
458 | if (iter->doi == doi && iter->valid) | |
459 | return iter; | |
460 | return NULL; | |
461 | } | |
462 | ||
463 | /** | |
464 | * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine | |
465 | * @doi_def: the DOI structure | |
466 | * | |
467 | * Description: | |
468 | * The caller defines a new DOI for use by the CIPSO engine and calls this | |
469 | * function to add it to the list of acceptable domains. The caller must | |
470 | * ensure that the mapping table specified in @doi_def->map meets all of the | |
471 | * requirements of the mapping type (see cipso_ipv4.h for details). Returns | |
472 | * zero on success and non-zero on failure. | |
473 | * | |
474 | */ | |
475 | int cipso_v4_doi_add(struct cipso_v4_doi *doi_def) | |
476 | { | |
6ce61a7c PM |
477 | u32 iter; |
478 | ||
446fda4f PM |
479 | if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN) |
480 | return -EINVAL; | |
6ce61a7c PM |
481 | for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) { |
482 | switch (doi_def->tags[iter]) { | |
483 | case CIPSO_V4_TAG_RBITMAP: | |
484 | break; | |
484b3669 PM |
485 | case CIPSO_V4_TAG_RANGE: |
486 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
487 | return -EINVAL; | |
488 | break; | |
6ce61a7c PM |
489 | case CIPSO_V4_TAG_INVALID: |
490 | if (iter == 0) | |
491 | return -EINVAL; | |
492 | break; | |
654bbc2a PM |
493 | case CIPSO_V4_TAG_ENUM: |
494 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
495 | return -EINVAL; | |
496 | break; | |
6ce61a7c PM |
497 | default: |
498 | return -EINVAL; | |
499 | } | |
500 | } | |
446fda4f PM |
501 | |
502 | doi_def->valid = 1; | |
503 | INIT_RCU_HEAD(&doi_def->rcu); | |
504 | INIT_LIST_HEAD(&doi_def->dom_list); | |
505 | ||
506 | rcu_read_lock(); | |
507 | if (cipso_v4_doi_search(doi_def->doi) != NULL) | |
508 | goto doi_add_failure_rlock; | |
509 | spin_lock(&cipso_v4_doi_list_lock); | |
510 | if (cipso_v4_doi_search(doi_def->doi) != NULL) | |
511 | goto doi_add_failure_slock; | |
512 | list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list); | |
513 | spin_unlock(&cipso_v4_doi_list_lock); | |
514 | rcu_read_unlock(); | |
515 | ||
516 | return 0; | |
517 | ||
518 | doi_add_failure_slock: | |
519 | spin_unlock(&cipso_v4_doi_list_lock); | |
520 | doi_add_failure_rlock: | |
521 | rcu_read_unlock(); | |
522 | return -EEXIST; | |
523 | } | |
524 | ||
525 | /** | |
526 | * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine | |
527 | * @doi: the DOI value | |
32f50cde | 528 | * @audit_secid: the LSM secid to use in the audit message |
446fda4f PM |
529 | * @callback: the DOI cleanup/free callback |
530 | * | |
531 | * Description: | |
532 | * Removes a DOI definition from the CIPSO engine, @callback is called to | |
533 | * free any memory. The NetLabel routines will be called to release their own | |
534 | * LSM domain mappings as well as our own domain list. Returns zero on | |
535 | * success and negative values on failure. | |
536 | * | |
537 | */ | |
32f50cde | 538 | int cipso_v4_doi_remove(u32 doi, |
95d4e6be | 539 | struct netlbl_audit *audit_info, |
32f50cde | 540 | void (*callback) (struct rcu_head * head)) |
446fda4f PM |
541 | { |
542 | struct cipso_v4_doi *doi_def; | |
543 | struct cipso_v4_domhsh_entry *dom_iter; | |
544 | ||
545 | rcu_read_lock(); | |
546 | if (cipso_v4_doi_search(doi) != NULL) { | |
547 | spin_lock(&cipso_v4_doi_list_lock); | |
548 | doi_def = cipso_v4_doi_search(doi); | |
549 | if (doi_def == NULL) { | |
550 | spin_unlock(&cipso_v4_doi_list_lock); | |
551 | rcu_read_unlock(); | |
552 | return -ENOENT; | |
553 | } | |
554 | doi_def->valid = 0; | |
555 | list_del_rcu(&doi_def->list); | |
556 | spin_unlock(&cipso_v4_doi_list_lock); | |
557 | list_for_each_entry_rcu(dom_iter, &doi_def->dom_list, list) | |
558 | if (dom_iter->valid) | |
32f50cde | 559 | netlbl_domhsh_remove(dom_iter->domain, |
95d4e6be | 560 | audit_info); |
446fda4f PM |
561 | cipso_v4_cache_invalidate(); |
562 | rcu_read_unlock(); | |
563 | ||
564 | call_rcu(&doi_def->rcu, callback); | |
565 | return 0; | |
566 | } | |
567 | rcu_read_unlock(); | |
568 | ||
569 | return -ENOENT; | |
570 | } | |
571 | ||
572 | /** | |
573 | * cipso_v4_doi_getdef - Returns a pointer to a valid DOI definition | |
574 | * @doi: the DOI value | |
575 | * | |
576 | * Description: | |
577 | * Searches for a valid DOI definition and if one is found it is returned to | |
578 | * the caller. Otherwise NULL is returned. The caller must ensure that | |
579 | * rcu_read_lock() is held while accessing the returned definition. | |
580 | * | |
581 | */ | |
582 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) | |
583 | { | |
584 | return cipso_v4_doi_search(doi); | |
585 | } | |
586 | ||
587 | /** | |
fcd48280 PM |
588 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
589 | * @skip_cnt: skip past this number of DOI definitions, updated | |
590 | * @callback: callback for each DOI definition | |
591 | * @cb_arg: argument for the callback function | |
446fda4f PM |
592 | * |
593 | * Description: | |
fcd48280 PM |
594 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
595 | * For each entry call @callback, if @callback returns a negative value stop | |
596 | * 'walking' through the list and return. Updates the value in @skip_cnt upon | |
597 | * return. Returns zero on success, negative values on failure. | |
446fda4f PM |
598 | * |
599 | */ | |
fcd48280 PM |
600 | int cipso_v4_doi_walk(u32 *skip_cnt, |
601 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), | |
602 | void *cb_arg) | |
446fda4f | 603 | { |
fcd48280 | 604 | int ret_val = -ENOENT; |
446fda4f | 605 | u32 doi_cnt = 0; |
fcd48280 | 606 | struct cipso_v4_doi *iter_doi; |
446fda4f | 607 | |
446fda4f | 608 | rcu_read_lock(); |
fcd48280 PM |
609 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
610 | if (iter_doi->valid) { | |
611 | if (doi_cnt++ < *skip_cnt) | |
612 | continue; | |
613 | ret_val = callback(iter_doi, cb_arg); | |
614 | if (ret_val < 0) { | |
615 | doi_cnt--; | |
616 | goto doi_walk_return; | |
446fda4f | 617 | } |
446fda4f | 618 | } |
446fda4f | 619 | |
fcd48280 | 620 | doi_walk_return: |
446fda4f | 621 | rcu_read_unlock(); |
fcd48280 PM |
622 | *skip_cnt = doi_cnt; |
623 | return ret_val; | |
446fda4f PM |
624 | } |
625 | ||
626 | /** | |
627 | * cipso_v4_doi_domhsh_add - Adds a domain entry to a DOI definition | |
628 | * @doi_def: the DOI definition | |
629 | * @domain: the domain to add | |
630 | * | |
631 | * Description: | |
632 | * Adds the @domain to the the DOI specified by @doi_def, this function | |
633 | * should only be called by external functions (i.e. NetLabel). This function | |
634 | * does allocate memory. Returns zero on success, negative values on failure. | |
635 | * | |
636 | */ | |
637 | int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, const char *domain) | |
638 | { | |
639 | struct cipso_v4_domhsh_entry *iter; | |
640 | struct cipso_v4_domhsh_entry *new_dom; | |
641 | ||
642 | new_dom = kzalloc(sizeof(*new_dom), GFP_KERNEL); | |
643 | if (new_dom == NULL) | |
644 | return -ENOMEM; | |
645 | if (domain) { | |
646 | new_dom->domain = kstrdup(domain, GFP_KERNEL); | |
647 | if (new_dom->domain == NULL) { | |
648 | kfree(new_dom); | |
649 | return -ENOMEM; | |
650 | } | |
651 | } | |
652 | new_dom->valid = 1; | |
653 | INIT_RCU_HEAD(&new_dom->rcu); | |
654 | ||
655 | rcu_read_lock(); | |
656 | spin_lock(&cipso_v4_doi_list_lock); | |
657 | list_for_each_entry_rcu(iter, &doi_def->dom_list, list) | |
658 | if (iter->valid && | |
659 | ((domain != NULL && iter->domain != NULL && | |
660 | strcmp(iter->domain, domain) == 0) || | |
661 | (domain == NULL && iter->domain == NULL))) { | |
662 | spin_unlock(&cipso_v4_doi_list_lock); | |
663 | rcu_read_unlock(); | |
664 | kfree(new_dom->domain); | |
665 | kfree(new_dom); | |
666 | return -EEXIST; | |
667 | } | |
668 | list_add_tail_rcu(&new_dom->list, &doi_def->dom_list); | |
669 | spin_unlock(&cipso_v4_doi_list_lock); | |
670 | rcu_read_unlock(); | |
671 | ||
672 | return 0; | |
673 | } | |
674 | ||
675 | /** | |
676 | * cipso_v4_doi_domhsh_remove - Removes a domain entry from a DOI definition | |
677 | * @doi_def: the DOI definition | |
678 | * @domain: the domain to remove | |
679 | * | |
680 | * Description: | |
681 | * Removes the @domain from the DOI specified by @doi_def, this function | |
682 | * should only be called by external functions (i.e. NetLabel). Returns zero | |
683 | * on success and negative values on error. | |
684 | * | |
685 | */ | |
686 | int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def, | |
687 | const char *domain) | |
688 | { | |
689 | struct cipso_v4_domhsh_entry *iter; | |
690 | ||
691 | rcu_read_lock(); | |
692 | spin_lock(&cipso_v4_doi_list_lock); | |
693 | list_for_each_entry_rcu(iter, &doi_def->dom_list, list) | |
694 | if (iter->valid && | |
695 | ((domain != NULL && iter->domain != NULL && | |
696 | strcmp(iter->domain, domain) == 0) || | |
697 | (domain == NULL && iter->domain == NULL))) { | |
698 | iter->valid = 0; | |
699 | list_del_rcu(&iter->list); | |
700 | spin_unlock(&cipso_v4_doi_list_lock); | |
701 | rcu_read_unlock(); | |
702 | call_rcu(&iter->rcu, cipso_v4_doi_domhsh_free); | |
703 | ||
704 | return 0; | |
705 | } | |
706 | spin_unlock(&cipso_v4_doi_list_lock); | |
707 | rcu_read_unlock(); | |
708 | ||
709 | return -ENOENT; | |
710 | } | |
711 | ||
712 | /* | |
713 | * Label Mapping Functions | |
714 | */ | |
715 | ||
716 | /** | |
717 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood | |
718 | * @doi_def: the DOI definition | |
719 | * @level: the level to check | |
720 | * | |
721 | * Description: | |
722 | * Checks the given level against the given DOI definition and returns a | |
723 | * negative value if the level does not have a valid mapping and a zero value | |
724 | * if the level is defined by the DOI. | |
725 | * | |
726 | */ | |
727 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) | |
728 | { | |
729 | switch (doi_def->type) { | |
730 | case CIPSO_V4_MAP_PASS: | |
731 | return 0; | |
732 | case CIPSO_V4_MAP_STD: | |
733 | if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL) | |
734 | return 0; | |
735 | break; | |
736 | } | |
737 | ||
738 | return -EFAULT; | |
739 | } | |
740 | ||
741 | /** | |
742 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network | |
743 | * @doi_def: the DOI definition | |
744 | * @host_lvl: the host MLS level | |
745 | * @net_lvl: the network/CIPSO MLS level | |
746 | * | |
747 | * Description: | |
748 | * Perform a label mapping to translate a local MLS level to the correct | |
749 | * CIPSO level using the given DOI definition. Returns zero on success, | |
750 | * negative values otherwise. | |
751 | * | |
752 | */ | |
753 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, | |
754 | u32 host_lvl, | |
755 | u32 *net_lvl) | |
756 | { | |
757 | switch (doi_def->type) { | |
758 | case CIPSO_V4_MAP_PASS: | |
759 | *net_lvl = host_lvl; | |
760 | return 0; | |
761 | case CIPSO_V4_MAP_STD: | |
c6387a86 PM |
762 | if (host_lvl < doi_def->map.std->lvl.local_size && |
763 | doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) { | |
446fda4f PM |
764 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
765 | return 0; | |
766 | } | |
c6387a86 | 767 | return -EPERM; |
446fda4f PM |
768 | } |
769 | ||
770 | return -EINVAL; | |
771 | } | |
772 | ||
773 | /** | |
774 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host | |
775 | * @doi_def: the DOI definition | |
776 | * @net_lvl: the network/CIPSO MLS level | |
777 | * @host_lvl: the host MLS level | |
778 | * | |
779 | * Description: | |
780 | * Perform a label mapping to translate a CIPSO level to the correct local MLS | |
781 | * level using the given DOI definition. Returns zero on success, negative | |
782 | * values otherwise. | |
783 | * | |
784 | */ | |
785 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, | |
786 | u32 net_lvl, | |
787 | u32 *host_lvl) | |
788 | { | |
789 | struct cipso_v4_std_map_tbl *map_tbl; | |
790 | ||
791 | switch (doi_def->type) { | |
792 | case CIPSO_V4_MAP_PASS: | |
793 | *host_lvl = net_lvl; | |
794 | return 0; | |
795 | case CIPSO_V4_MAP_STD: | |
796 | map_tbl = doi_def->map.std; | |
797 | if (net_lvl < map_tbl->lvl.cipso_size && | |
798 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { | |
799 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; | |
800 | return 0; | |
801 | } | |
c6387a86 | 802 | return -EPERM; |
446fda4f PM |
803 | } |
804 | ||
805 | return -EINVAL; | |
806 | } | |
807 | ||
808 | /** | |
809 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid | |
810 | * @doi_def: the DOI definition | |
811 | * @bitmap: category bitmap | |
812 | * @bitmap_len: bitmap length in bytes | |
813 | * | |
814 | * Description: | |
815 | * Checks the given category bitmap against the given DOI definition and | |
816 | * returns a negative value if any of the categories in the bitmap do not have | |
817 | * a valid mapping and a zero value if all of the categories are valid. | |
818 | * | |
819 | */ | |
820 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, | |
821 | const unsigned char *bitmap, | |
822 | u32 bitmap_len) | |
823 | { | |
824 | int cat = -1; | |
825 | u32 bitmap_len_bits = bitmap_len * 8; | |
044a68ed PM |
826 | u32 cipso_cat_size; |
827 | u32 *cipso_array; | |
446fda4f PM |
828 | |
829 | switch (doi_def->type) { | |
830 | case CIPSO_V4_MAP_PASS: | |
831 | return 0; | |
832 | case CIPSO_V4_MAP_STD: | |
044a68ed PM |
833 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
834 | cipso_array = doi_def->map.std->cat.cipso; | |
446fda4f PM |
835 | for (;;) { |
836 | cat = cipso_v4_bitmap_walk(bitmap, | |
837 | bitmap_len_bits, | |
838 | cat + 1, | |
839 | 1); | |
840 | if (cat < 0) | |
841 | break; | |
842 | if (cat >= cipso_cat_size || | |
843 | cipso_array[cat] >= CIPSO_V4_INV_CAT) | |
844 | return -EFAULT; | |
845 | } | |
846 | ||
847 | if (cat == -1) | |
848 | return 0; | |
849 | break; | |
850 | } | |
851 | ||
852 | return -EFAULT; | |
853 | } | |
854 | ||
855 | /** | |
856 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network | |
857 | * @doi_def: the DOI definition | |
02752760 | 858 | * @secattr: the security attributes |
446fda4f PM |
859 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
860 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
861 | * | |
862 | * Description: | |
863 | * Perform a label mapping to translate a local MLS category bitmap to the | |
864 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum | |
865 | * size in bytes of the network bitmap on success, negative values otherwise. | |
866 | * | |
867 | */ | |
868 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, | |
02752760 | 869 | const struct netlbl_lsm_secattr *secattr, |
446fda4f PM |
870 | unsigned char *net_cat, |
871 | u32 net_cat_len) | |
872 | { | |
873 | int host_spot = -1; | |
02752760 | 874 | u32 net_spot = CIPSO_V4_INV_CAT; |
446fda4f | 875 | u32 net_spot_max = 0; |
446fda4f | 876 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
877 | u32 host_cat_size = 0; |
878 | u32 *host_cat_array = NULL; | |
446fda4f | 879 | |
02752760 | 880 | if (doi_def->type == CIPSO_V4_MAP_STD) { |
044a68ed PM |
881 | host_cat_size = doi_def->map.std->cat.local_size; |
882 | host_cat_array = doi_def->map.std->cat.local; | |
02752760 PM |
883 | } |
884 | ||
885 | for (;;) { | |
886 | host_spot = netlbl_secattr_catmap_walk(secattr->mls_cat, | |
887 | host_spot + 1); | |
888 | if (host_spot < 0) | |
889 | break; | |
890 | ||
891 | switch (doi_def->type) { | |
892 | case CIPSO_V4_MAP_PASS: | |
893 | net_spot = host_spot; | |
894 | break; | |
895 | case CIPSO_V4_MAP_STD: | |
446fda4f PM |
896 | if (host_spot >= host_cat_size) |
897 | return -EPERM; | |
446fda4f | 898 | net_spot = host_cat_array[host_spot]; |
9fade4bf PM |
899 | if (net_spot >= CIPSO_V4_INV_CAT) |
900 | return -EPERM; | |
02752760 | 901 | break; |
446fda4f | 902 | } |
02752760 PM |
903 | if (net_spot >= net_clen_bits) |
904 | return -ENOSPC; | |
905 | cipso_v4_bitmap_setbit(net_cat, net_spot, 1); | |
446fda4f | 906 | |
02752760 PM |
907 | if (net_spot > net_spot_max) |
908 | net_spot_max = net_spot; | |
446fda4f PM |
909 | } |
910 | ||
02752760 PM |
911 | if (++net_spot_max % 8) |
912 | return net_spot_max / 8 + 1; | |
913 | return net_spot_max / 8; | |
446fda4f PM |
914 | } |
915 | ||
916 | /** | |
917 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host | |
918 | * @doi_def: the DOI definition | |
919 | * @net_cat: the category bitmap in network/CIPSO format | |
920 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
02752760 | 921 | * @secattr: the security attributes |
446fda4f PM |
922 | * |
923 | * Description: | |
924 | * Perform a label mapping to translate a CIPSO bitmap to the correct local | |
02752760 PM |
925 | * MLS category bitmap using the given DOI definition. Returns zero on |
926 | * success, negative values on failure. | |
446fda4f PM |
927 | * |
928 | */ | |
929 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, | |
930 | const unsigned char *net_cat, | |
931 | u32 net_cat_len, | |
02752760 | 932 | struct netlbl_lsm_secattr *secattr) |
446fda4f | 933 | { |
02752760 | 934 | int ret_val; |
446fda4f | 935 | int net_spot = -1; |
02752760 | 936 | u32 host_spot = CIPSO_V4_INV_CAT; |
446fda4f | 937 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
938 | u32 net_cat_size = 0; |
939 | u32 *net_cat_array = NULL; | |
446fda4f | 940 | |
02752760 | 941 | if (doi_def->type == CIPSO_V4_MAP_STD) { |
044a68ed PM |
942 | net_cat_size = doi_def->map.std->cat.cipso_size; |
943 | net_cat_array = doi_def->map.std->cat.cipso; | |
02752760 | 944 | } |
446fda4f | 945 | |
02752760 PM |
946 | for (;;) { |
947 | net_spot = cipso_v4_bitmap_walk(net_cat, | |
948 | net_clen_bits, | |
949 | net_spot + 1, | |
950 | 1); | |
951 | if (net_spot < 0) { | |
952 | if (net_spot == -2) | |
953 | return -EFAULT; | |
954 | return 0; | |
955 | } | |
956 | ||
957 | switch (doi_def->type) { | |
958 | case CIPSO_V4_MAP_PASS: | |
959 | host_spot = net_spot; | |
960 | break; | |
961 | case CIPSO_V4_MAP_STD: | |
962 | if (net_spot >= net_cat_size) | |
963 | return -EPERM; | |
446fda4f | 964 | host_spot = net_cat_array[net_spot]; |
9fade4bf PM |
965 | if (host_spot >= CIPSO_V4_INV_CAT) |
966 | return -EPERM; | |
02752760 | 967 | break; |
446fda4f | 968 | } |
02752760 PM |
969 | ret_val = netlbl_secattr_catmap_setbit(secattr->mls_cat, |
970 | host_spot, | |
971 | GFP_ATOMIC); | |
972 | if (ret_val != 0) | |
973 | return ret_val; | |
446fda4f PM |
974 | } |
975 | ||
976 | return -EINVAL; | |
977 | } | |
978 | ||
654bbc2a PM |
979 | /** |
980 | * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid | |
981 | * @doi_def: the DOI definition | |
982 | * @enumcat: category list | |
983 | * @enumcat_len: length of the category list in bytes | |
984 | * | |
985 | * Description: | |
986 | * Checks the given categories against the given DOI definition and returns a | |
987 | * negative value if any of the categories do not have a valid mapping and a | |
988 | * zero value if all of the categories are valid. | |
989 | * | |
990 | */ | |
991 | static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, | |
992 | const unsigned char *enumcat, | |
993 | u32 enumcat_len) | |
994 | { | |
995 | u16 cat; | |
996 | int cat_prev = -1; | |
997 | u32 iter; | |
998 | ||
999 | if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01) | |
1000 | return -EFAULT; | |
1001 | ||
1002 | for (iter = 0; iter < enumcat_len; iter += 2) { | |
1003 | cat = ntohs(*((__be16 *)&enumcat[iter])); | |
1004 | if (cat <= cat_prev) | |
1005 | return -EFAULT; | |
1006 | cat_prev = cat; | |
1007 | } | |
1008 | ||
1009 | return 0; | |
1010 | } | |
1011 | ||
1012 | /** | |
1013 | * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network | |
1014 | * @doi_def: the DOI definition | |
1015 | * @secattr: the security attributes | |
1016 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1017 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1018 | * | |
1019 | * Description: | |
1020 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1021 | * correct CIPSO category list using the given DOI definition. Returns the | |
1022 | * size in bytes of the network category bitmap on success, negative values | |
1023 | * otherwise. | |
1024 | * | |
1025 | */ | |
1026 | static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, | |
1027 | const struct netlbl_lsm_secattr *secattr, | |
1028 | unsigned char *net_cat, | |
1029 | u32 net_cat_len) | |
1030 | { | |
1031 | int cat = -1; | |
1032 | u32 cat_iter = 0; | |
1033 | ||
1034 | for (;;) { | |
1035 | cat = netlbl_secattr_catmap_walk(secattr->mls_cat, cat + 1); | |
1036 | if (cat < 0) | |
1037 | break; | |
1038 | if ((cat_iter + 2) > net_cat_len) | |
1039 | return -ENOSPC; | |
1040 | ||
1041 | *((__be16 *)&net_cat[cat_iter]) = htons(cat); | |
1042 | cat_iter += 2; | |
1043 | } | |
1044 | ||
1045 | return cat_iter; | |
1046 | } | |
1047 | ||
1048 | /** | |
1049 | * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host | |
1050 | * @doi_def: the DOI definition | |
1051 | * @net_cat: the category list in network/CIPSO format | |
1052 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1053 | * @secattr: the security attributes | |
1054 | * | |
1055 | * Description: | |
1056 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1057 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1058 | * success, negative values on failure. | |
1059 | * | |
1060 | */ | |
1061 | static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, | |
1062 | const unsigned char *net_cat, | |
1063 | u32 net_cat_len, | |
1064 | struct netlbl_lsm_secattr *secattr) | |
1065 | { | |
1066 | int ret_val; | |
1067 | u32 iter; | |
1068 | ||
1069 | for (iter = 0; iter < net_cat_len; iter += 2) { | |
1070 | ret_val = netlbl_secattr_catmap_setbit(secattr->mls_cat, | |
1071 | ntohs(*((__be16 *)&net_cat[iter])), | |
1072 | GFP_ATOMIC); | |
1073 | if (ret_val != 0) | |
1074 | return ret_val; | |
1075 | } | |
1076 | ||
1077 | return 0; | |
1078 | } | |
1079 | ||
484b3669 PM |
1080 | /** |
1081 | * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid | |
1082 | * @doi_def: the DOI definition | |
1083 | * @rngcat: category list | |
1084 | * @rngcat_len: length of the category list in bytes | |
1085 | * | |
1086 | * Description: | |
1087 | * Checks the given categories against the given DOI definition and returns a | |
1088 | * negative value if any of the categories do not have a valid mapping and a | |
1089 | * zero value if all of the categories are valid. | |
1090 | * | |
1091 | */ | |
1092 | static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, | |
1093 | const unsigned char *rngcat, | |
1094 | u32 rngcat_len) | |
1095 | { | |
1096 | u16 cat_high; | |
1097 | u16 cat_low; | |
1098 | u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1; | |
1099 | u32 iter; | |
1100 | ||
1101 | if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01) | |
1102 | return -EFAULT; | |
1103 | ||
1104 | for (iter = 0; iter < rngcat_len; iter += 4) { | |
1105 | cat_high = ntohs(*((__be16 *)&rngcat[iter])); | |
1106 | if ((iter + 4) <= rngcat_len) | |
1107 | cat_low = ntohs(*((__be16 *)&rngcat[iter + 2])); | |
1108 | else | |
1109 | cat_low = 0; | |
1110 | ||
1111 | if (cat_high > cat_prev) | |
1112 | return -EFAULT; | |
1113 | ||
1114 | cat_prev = cat_low; | |
1115 | } | |
1116 | ||
1117 | return 0; | |
1118 | } | |
1119 | ||
1120 | /** | |
1121 | * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network | |
1122 | * @doi_def: the DOI definition | |
1123 | * @secattr: the security attributes | |
1124 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1125 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1126 | * | |
1127 | * Description: | |
1128 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1129 | * correct CIPSO category list using the given DOI definition. Returns the | |
1130 | * size in bytes of the network category bitmap on success, negative values | |
1131 | * otherwise. | |
1132 | * | |
1133 | */ | |
1134 | static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, | |
1135 | const struct netlbl_lsm_secattr *secattr, | |
1136 | unsigned char *net_cat, | |
1137 | u32 net_cat_len) | |
1138 | { | |
484b3669 | 1139 | int iter = -1; |
f998e8cb | 1140 | u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2]; |
484b3669 PM |
1141 | u32 array_cnt = 0; |
1142 | u32 cat_size = 0; | |
1143 | ||
f998e8cb | 1144 | /* make sure we don't overflow the 'array[]' variable */ |
128c6b6c PM |
1145 | if (net_cat_len > |
1146 | (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN)) | |
1147 | return -ENOSPC; | |
484b3669 PM |
1148 | |
1149 | for (;;) { | |
1150 | iter = netlbl_secattr_catmap_walk(secattr->mls_cat, iter + 1); | |
1151 | if (iter < 0) | |
1152 | break; | |
1153 | cat_size += (iter == 0 ? 0 : sizeof(u16)); | |
1154 | if (cat_size > net_cat_len) | |
1155 | return -ENOSPC; | |
1156 | array[array_cnt++] = iter; | |
1157 | ||
1158 | iter = netlbl_secattr_catmap_walk_rng(secattr->mls_cat, iter); | |
1159 | if (iter < 0) | |
1160 | return -EFAULT; | |
1161 | cat_size += sizeof(u16); | |
1162 | if (cat_size > net_cat_len) | |
1163 | return -ENOSPC; | |
1164 | array[array_cnt++] = iter; | |
1165 | } | |
1166 | ||
1167 | for (iter = 0; array_cnt > 0;) { | |
1168 | *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]); | |
1169 | iter += 2; | |
1170 | array_cnt--; | |
1171 | if (array[array_cnt] != 0) { | |
1172 | *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]); | |
1173 | iter += 2; | |
1174 | } | |
1175 | } | |
1176 | ||
1177 | return cat_size; | |
1178 | } | |
1179 | ||
1180 | /** | |
1181 | * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host | |
1182 | * @doi_def: the DOI definition | |
1183 | * @net_cat: the category list in network/CIPSO format | |
1184 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1185 | * @secattr: the security attributes | |
1186 | * | |
1187 | * Description: | |
1188 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1189 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1190 | * success, negative values on failure. | |
1191 | * | |
1192 | */ | |
1193 | static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, | |
1194 | const unsigned char *net_cat, | |
1195 | u32 net_cat_len, | |
1196 | struct netlbl_lsm_secattr *secattr) | |
1197 | { | |
1198 | int ret_val; | |
1199 | u32 net_iter; | |
1200 | u16 cat_low; | |
1201 | u16 cat_high; | |
1202 | ||
132adf54 | 1203 | for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) { |
484b3669 PM |
1204 | cat_high = ntohs(*((__be16 *)&net_cat[net_iter])); |
1205 | if ((net_iter + 4) <= net_cat_len) | |
1206 | cat_low = ntohs(*((__be16 *)&net_cat[net_iter + 2])); | |
1207 | else | |
1208 | cat_low = 0; | |
1209 | ||
1210 | ret_val = netlbl_secattr_catmap_setrng(secattr->mls_cat, | |
1211 | cat_low, | |
1212 | cat_high, | |
1213 | GFP_ATOMIC); | |
1214 | if (ret_val != 0) | |
1215 | return ret_val; | |
1216 | } | |
1217 | ||
1218 | return 0; | |
1219 | } | |
1220 | ||
446fda4f PM |
1221 | /* |
1222 | * Protocol Handling Functions | |
1223 | */ | |
1224 | ||
446fda4f PM |
1225 | /** |
1226 | * cipso_v4_gentag_hdr - Generate a CIPSO option header | |
1227 | * @doi_def: the DOI definition | |
91b1ed0a | 1228 | * @len: the total tag length in bytes, not including this header |
446fda4f PM |
1229 | * @buf: the CIPSO option buffer |
1230 | * | |
1231 | * Description: | |
91b1ed0a | 1232 | * Write a CIPSO header into the beginning of @buffer. |
446fda4f PM |
1233 | * |
1234 | */ | |
91b1ed0a PM |
1235 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
1236 | unsigned char *buf, | |
1237 | u32 len) | |
446fda4f | 1238 | { |
446fda4f PM |
1239 | buf[0] = IPOPT_CIPSO; |
1240 | buf[1] = CIPSO_V4_HDR_LEN + len; | |
714e85be | 1241 | *(__be32 *)&buf[2] = htonl(doi_def->doi); |
446fda4f PM |
1242 | } |
1243 | ||
446fda4f PM |
1244 | /** |
1245 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) | |
1246 | * @doi_def: the DOI definition | |
1247 | * @secattr: the security attributes | |
1248 | * @buffer: the option buffer | |
1249 | * @buffer_len: length of buffer in bytes | |
1250 | * | |
1251 | * Description: | |
1252 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The | |
1253 | * actual buffer length may be larger than the indicated size due to | |
91b1ed0a PM |
1254 | * translation between host and network category bitmaps. Returns the size of |
1255 | * the tag on success, negative values on failure. | |
446fda4f PM |
1256 | * |
1257 | */ | |
1258 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, | |
1259 | const struct netlbl_lsm_secattr *secattr, | |
91b1ed0a PM |
1260 | unsigned char *buffer, |
1261 | u32 buffer_len) | |
446fda4f | 1262 | { |
701a90ba | 1263 | int ret_val; |
91b1ed0a | 1264 | u32 tag_len; |
446fda4f PM |
1265 | u32 level; |
1266 | ||
701a90ba PM |
1267 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
1268 | return -EPERM; | |
1269 | ||
91b1ed0a PM |
1270 | ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level); |
1271 | if (ret_val != 0) | |
1272 | return ret_val; | |
446fda4f | 1273 | |
91b1ed0a | 1274 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
446fda4f | 1275 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
02752760 | 1276 | secattr, |
91b1ed0a PM |
1277 | &buffer[4], |
1278 | buffer_len - 4); | |
446fda4f | 1279 | if (ret_val < 0) |
91b1ed0a | 1280 | return ret_val; |
446fda4f PM |
1281 | |
1282 | /* This will send packets using the "optimized" format when | |
1283 | * possibile as specified in section 3.4.2.6 of the | |
1284 | * CIPSO draft. */ | |
701a90ba | 1285 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
91b1ed0a | 1286 | tag_len = 14; |
701a90ba | 1287 | else |
91b1ed0a PM |
1288 | tag_len = 4 + ret_val; |
1289 | } else | |
1290 | tag_len = 4; | |
446fda4f | 1291 | |
91b1ed0a PM |
1292 | buffer[0] = 0x01; |
1293 | buffer[1] = tag_len; | |
1294 | buffer[3] = level; | |
446fda4f | 1295 | |
91b1ed0a | 1296 | return tag_len; |
446fda4f PM |
1297 | } |
1298 | ||
1299 | /** | |
1300 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag | |
1301 | * @doi_def: the DOI definition | |
1302 | * @tag: the CIPSO tag | |
1303 | * @secattr: the security attributes | |
1304 | * | |
1305 | * Description: | |
1306 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security | |
1307 | * attributes in @secattr. Return zero on success, negatives values on | |
1308 | * failure. | |
1309 | * | |
1310 | */ | |
1311 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, | |
1312 | const unsigned char *tag, | |
1313 | struct netlbl_lsm_secattr *secattr) | |
1314 | { | |
1315 | int ret_val; | |
1316 | u8 tag_len = tag[1]; | |
1317 | u32 level; | |
1318 | ||
1319 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1320 | if (ret_val != 0) | |
1321 | return ret_val; | |
1322 | secattr->mls_lvl = level; | |
701a90ba | 1323 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
446fda4f PM |
1324 | |
1325 | if (tag_len > 4) { | |
02752760 | 1326 | secattr->mls_cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); |
446fda4f PM |
1327 | if (secattr->mls_cat == NULL) |
1328 | return -ENOMEM; | |
1329 | ||
1330 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, | |
1331 | &tag[4], | |
1332 | tag_len - 4, | |
02752760 PM |
1333 | secattr); |
1334 | if (ret_val != 0) { | |
1335 | netlbl_secattr_catmap_free(secattr->mls_cat); | |
446fda4f PM |
1336 | return ret_val; |
1337 | } | |
02752760 PM |
1338 | |
1339 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
446fda4f PM |
1340 | } |
1341 | ||
1342 | return 0; | |
1343 | } | |
1344 | ||
654bbc2a PM |
1345 | /** |
1346 | * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) | |
1347 | * @doi_def: the DOI definition | |
1348 | * @secattr: the security attributes | |
1349 | * @buffer: the option buffer | |
1350 | * @buffer_len: length of buffer in bytes | |
1351 | * | |
1352 | * Description: | |
1353 | * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the | |
1354 | * size of the tag on success, negative values on failure. | |
1355 | * | |
1356 | */ | |
1357 | static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, | |
1358 | const struct netlbl_lsm_secattr *secattr, | |
1359 | unsigned char *buffer, | |
1360 | u32 buffer_len) | |
1361 | { | |
1362 | int ret_val; | |
1363 | u32 tag_len; | |
1364 | u32 level; | |
1365 | ||
1366 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1367 | return -EPERM; | |
1368 | ||
1369 | ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level); | |
1370 | if (ret_val != 0) | |
1371 | return ret_val; | |
1372 | ||
1373 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1374 | ret_val = cipso_v4_map_cat_enum_hton(doi_def, | |
1375 | secattr, | |
1376 | &buffer[4], | |
1377 | buffer_len - 4); | |
1378 | if (ret_val < 0) | |
1379 | return ret_val; | |
1380 | ||
1381 | tag_len = 4 + ret_val; | |
1382 | } else | |
1383 | tag_len = 4; | |
1384 | ||
1385 | buffer[0] = 0x02; | |
1386 | buffer[1] = tag_len; | |
1387 | buffer[3] = level; | |
1388 | ||
1389 | return tag_len; | |
1390 | } | |
1391 | ||
1392 | /** | |
1393 | * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag | |
1394 | * @doi_def: the DOI definition | |
1395 | * @tag: the CIPSO tag | |
1396 | * @secattr: the security attributes | |
1397 | * | |
1398 | * Description: | |
1399 | * Parse a CIPSO enumerated tag (tag type #2) and return the security | |
1400 | * attributes in @secattr. Return zero on success, negatives values on | |
1401 | * failure. | |
1402 | * | |
1403 | */ | |
1404 | static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, | |
1405 | const unsigned char *tag, | |
1406 | struct netlbl_lsm_secattr *secattr) | |
1407 | { | |
1408 | int ret_val; | |
1409 | u8 tag_len = tag[1]; | |
1410 | u32 level; | |
1411 | ||
1412 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1413 | if (ret_val != 0) | |
1414 | return ret_val; | |
1415 | secattr->mls_lvl = level; | |
1416 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; | |
1417 | ||
1418 | if (tag_len > 4) { | |
1419 | secattr->mls_cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); | |
1420 | if (secattr->mls_cat == NULL) | |
1421 | return -ENOMEM; | |
1422 | ||
1423 | ret_val = cipso_v4_map_cat_enum_ntoh(doi_def, | |
1424 | &tag[4], | |
1425 | tag_len - 4, | |
1426 | secattr); | |
1427 | if (ret_val != 0) { | |
1428 | netlbl_secattr_catmap_free(secattr->mls_cat); | |
1429 | return ret_val; | |
1430 | } | |
1431 | ||
1432 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1433 | } | |
1434 | ||
1435 | return 0; | |
1436 | } | |
1437 | ||
484b3669 PM |
1438 | /** |
1439 | * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) | |
1440 | * @doi_def: the DOI definition | |
1441 | * @secattr: the security attributes | |
1442 | * @buffer: the option buffer | |
1443 | * @buffer_len: length of buffer in bytes | |
1444 | * | |
1445 | * Description: | |
1446 | * Generate a CIPSO option using the ranged tag, tag type #5. Returns the | |
1447 | * size of the tag on success, negative values on failure. | |
1448 | * | |
1449 | */ | |
1450 | static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, | |
1451 | const struct netlbl_lsm_secattr *secattr, | |
1452 | unsigned char *buffer, | |
1453 | u32 buffer_len) | |
1454 | { | |
1455 | int ret_val; | |
1456 | u32 tag_len; | |
1457 | u32 level; | |
1458 | ||
1459 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1460 | return -EPERM; | |
1461 | ||
1462 | ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level); | |
1463 | if (ret_val != 0) | |
1464 | return ret_val; | |
1465 | ||
1466 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1467 | ret_val = cipso_v4_map_cat_rng_hton(doi_def, | |
1468 | secattr, | |
1469 | &buffer[4], | |
1470 | buffer_len - 4); | |
1471 | if (ret_val < 0) | |
1472 | return ret_val; | |
1473 | ||
1474 | tag_len = 4 + ret_val; | |
1475 | } else | |
1476 | tag_len = 4; | |
1477 | ||
1478 | buffer[0] = 0x05; | |
1479 | buffer[1] = tag_len; | |
1480 | buffer[3] = level; | |
1481 | ||
1482 | return tag_len; | |
1483 | } | |
1484 | ||
1485 | /** | |
1486 | * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag | |
1487 | * @doi_def: the DOI definition | |
1488 | * @tag: the CIPSO tag | |
1489 | * @secattr: the security attributes | |
1490 | * | |
1491 | * Description: | |
1492 | * Parse a CIPSO ranged tag (tag type #5) and return the security attributes | |
1493 | * in @secattr. Return zero on success, negatives values on failure. | |
1494 | * | |
1495 | */ | |
1496 | static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, | |
1497 | const unsigned char *tag, | |
1498 | struct netlbl_lsm_secattr *secattr) | |
1499 | { | |
1500 | int ret_val; | |
1501 | u8 tag_len = tag[1]; | |
1502 | u32 level; | |
1503 | ||
1504 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1505 | if (ret_val != 0) | |
1506 | return ret_val; | |
1507 | secattr->mls_lvl = level; | |
1508 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; | |
1509 | ||
1510 | if (tag_len > 4) { | |
1511 | secattr->mls_cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); | |
1512 | if (secattr->mls_cat == NULL) | |
1513 | return -ENOMEM; | |
1514 | ||
1515 | ret_val = cipso_v4_map_cat_rng_ntoh(doi_def, | |
1516 | &tag[4], | |
1517 | tag_len - 4, | |
1518 | secattr); | |
1519 | if (ret_val != 0) { | |
1520 | netlbl_secattr_catmap_free(secattr->mls_cat); | |
1521 | return ret_val; | |
1522 | } | |
1523 | ||
1524 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1525 | } | |
1526 | ||
1527 | return 0; | |
1528 | } | |
1529 | ||
446fda4f PM |
1530 | /** |
1531 | * cipso_v4_validate - Validate a CIPSO option | |
1532 | * @option: the start of the option, on error it is set to point to the error | |
1533 | * | |
1534 | * Description: | |
1535 | * This routine is called to validate a CIPSO option, it checks all of the | |
1536 | * fields to ensure that they are at least valid, see the draft snippet below | |
1537 | * for details. If the option is valid then a zero value is returned and | |
1538 | * the value of @option is unchanged. If the option is invalid then a | |
1539 | * non-zero value is returned and @option is adjusted to point to the | |
1540 | * offending portion of the option. From the IETF draft ... | |
1541 | * | |
1542 | * "If any field within the CIPSO options, such as the DOI identifier, is not | |
1543 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' | |
1544 | * (type 12) is generated and returned. The ICMP code field is set to 'bad | |
1545 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field | |
1546 | * that is unrecognized." | |
1547 | * | |
1548 | */ | |
1549 | int cipso_v4_validate(unsigned char **option) | |
1550 | { | |
1551 | unsigned char *opt = *option; | |
1552 | unsigned char *tag; | |
1553 | unsigned char opt_iter; | |
1554 | unsigned char err_offset = 0; | |
1555 | u8 opt_len; | |
1556 | u8 tag_len; | |
1557 | struct cipso_v4_doi *doi_def = NULL; | |
1558 | u32 tag_iter; | |
1559 | ||
1560 | /* caller already checks for length values that are too large */ | |
1561 | opt_len = opt[1]; | |
1562 | if (opt_len < 8) { | |
1563 | err_offset = 1; | |
1564 | goto validate_return; | |
1565 | } | |
1566 | ||
1567 | rcu_read_lock(); | |
66625984 | 1568 | doi_def = cipso_v4_doi_search(ntohl(*((__be32 *)&opt[2]))); |
446fda4f PM |
1569 | if (doi_def == NULL) { |
1570 | err_offset = 2; | |
1571 | goto validate_return_locked; | |
1572 | } | |
1573 | ||
1574 | opt_iter = 6; | |
1575 | tag = opt + opt_iter; | |
1576 | while (opt_iter < opt_len) { | |
1577 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) | |
1578 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || | |
1579 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { | |
1580 | err_offset = opt_iter; | |
1581 | goto validate_return_locked; | |
1582 | } | |
1583 | ||
1584 | tag_len = tag[1]; | |
1585 | if (tag_len > (opt_len - opt_iter)) { | |
1586 | err_offset = opt_iter + 1; | |
1587 | goto validate_return_locked; | |
1588 | } | |
1589 | ||
1590 | switch (tag[0]) { | |
1591 | case CIPSO_V4_TAG_RBITMAP: | |
1592 | if (tag_len < 4) { | |
1593 | err_offset = opt_iter + 1; | |
1594 | goto validate_return_locked; | |
1595 | } | |
1596 | ||
1597 | /* We are already going to do all the verification | |
1598 | * necessary at the socket layer so from our point of | |
1599 | * view it is safe to turn these checks off (and less | |
1600 | * work), however, the CIPSO draft says we should do | |
1601 | * all the CIPSO validations here but it doesn't | |
1602 | * really specify _exactly_ what we need to validate | |
1603 | * ... so, just make it a sysctl tunable. */ | |
1604 | if (cipso_v4_rbm_strictvalid) { | |
1605 | if (cipso_v4_map_lvl_valid(doi_def, | |
1606 | tag[3]) < 0) { | |
1607 | err_offset = opt_iter + 3; | |
1608 | goto validate_return_locked; | |
1609 | } | |
1610 | if (tag_len > 4 && | |
1611 | cipso_v4_map_cat_rbm_valid(doi_def, | |
1612 | &tag[4], | |
1613 | tag_len - 4) < 0) { | |
1614 | err_offset = opt_iter + 4; | |
1615 | goto validate_return_locked; | |
1616 | } | |
1617 | } | |
1618 | break; | |
654bbc2a PM |
1619 | case CIPSO_V4_TAG_ENUM: |
1620 | if (tag_len < 4) { | |
1621 | err_offset = opt_iter + 1; | |
1622 | goto validate_return_locked; | |
1623 | } | |
1624 | ||
1625 | if (cipso_v4_map_lvl_valid(doi_def, | |
1626 | tag[3]) < 0) { | |
1627 | err_offset = opt_iter + 3; | |
1628 | goto validate_return_locked; | |
1629 | } | |
1630 | if (tag_len > 4 && | |
1631 | cipso_v4_map_cat_enum_valid(doi_def, | |
1632 | &tag[4], | |
1633 | tag_len - 4) < 0) { | |
1634 | err_offset = opt_iter + 4; | |
1635 | goto validate_return_locked; | |
1636 | } | |
1637 | break; | |
484b3669 PM |
1638 | case CIPSO_V4_TAG_RANGE: |
1639 | if (tag_len < 4) { | |
1640 | err_offset = opt_iter + 1; | |
1641 | goto validate_return_locked; | |
1642 | } | |
1643 | ||
1644 | if (cipso_v4_map_lvl_valid(doi_def, | |
1645 | tag[3]) < 0) { | |
1646 | err_offset = opt_iter + 3; | |
1647 | goto validate_return_locked; | |
1648 | } | |
1649 | if (tag_len > 4 && | |
1650 | cipso_v4_map_cat_rng_valid(doi_def, | |
1651 | &tag[4], | |
1652 | tag_len - 4) < 0) { | |
1653 | err_offset = opt_iter + 4; | |
1654 | goto validate_return_locked; | |
1655 | } | |
1656 | break; | |
446fda4f PM |
1657 | default: |
1658 | err_offset = opt_iter; | |
1659 | goto validate_return_locked; | |
1660 | } | |
1661 | ||
1662 | tag += tag_len; | |
1663 | opt_iter += tag_len; | |
1664 | } | |
1665 | ||
1666 | validate_return_locked: | |
1667 | rcu_read_unlock(); | |
1668 | validate_return: | |
1669 | *option = opt + err_offset; | |
1670 | return err_offset; | |
1671 | } | |
1672 | ||
1673 | /** | |
1674 | * cipso_v4_error - Send the correct reponse for a bad packet | |
1675 | * @skb: the packet | |
1676 | * @error: the error code | |
1677 | * @gateway: CIPSO gateway flag | |
1678 | * | |
1679 | * Description: | |
1680 | * Based on the error code given in @error, send an ICMP error message back to | |
1681 | * the originating host. From the IETF draft ... | |
1682 | * | |
1683 | * "If the contents of the CIPSO [option] are valid but the security label is | |
1684 | * outside of the configured host or port label range, the datagram is | |
1685 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and | |
1686 | * returned. The code field of the ICMP is set to 'communication with | |
1687 | * destination network administratively prohibited' (code 9) or to | |
1688 | * 'communication with destination host administratively prohibited' | |
1689 | * (code 10). The value of the code is dependent on whether the originator | |
1690 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The | |
1691 | * recipient of the ICMP message MUST be able to handle either value. The | |
1692 | * same procedure is performed if a CIPSO [option] can not be added to an | |
1693 | * IP packet because it is too large to fit in the IP options area." | |
1694 | * | |
1695 | * "If the error is triggered by receipt of an ICMP message, the message is | |
1696 | * discarded and no response is permitted (consistent with general ICMP | |
1697 | * processing rules)." | |
1698 | * | |
1699 | */ | |
1700 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) | |
1701 | { | |
eddc9ec5 | 1702 | if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) |
446fda4f PM |
1703 | return; |
1704 | ||
1705 | if (gateway) | |
1706 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0); | |
1707 | else | |
1708 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0); | |
1709 | } | |
1710 | ||
1711 | /** | |
1712 | * cipso_v4_socket_setattr - Add a CIPSO option to a socket | |
1713 | * @sock: the socket | |
1714 | * @doi_def: the CIPSO DOI to use | |
1715 | * @secattr: the specific security attributes of the socket | |
1716 | * | |
1717 | * Description: | |
1718 | * Set the CIPSO option on the given socket using the DOI definition and | |
1719 | * security attributes passed to the function. This function requires | |
1720 | * exclusive access to @sock->sk, which means it either needs to be in the | |
1721 | * process of being created or locked via lock_sock(sock->sk). Returns zero on | |
1722 | * success and negative values on failure. | |
1723 | * | |
1724 | */ | |
1725 | int cipso_v4_socket_setattr(const struct socket *sock, | |
1726 | const struct cipso_v4_doi *doi_def, | |
1727 | const struct netlbl_lsm_secattr *secattr) | |
1728 | { | |
1729 | int ret_val = -EPERM; | |
1730 | u32 iter; | |
91b1ed0a | 1731 | unsigned char *buf; |
446fda4f PM |
1732 | u32 buf_len = 0; |
1733 | u32 opt_len; | |
1734 | struct ip_options *opt = NULL; | |
1735 | struct sock *sk; | |
1736 | struct inet_sock *sk_inet; | |
1737 | struct inet_connection_sock *sk_conn; | |
1738 | ||
1739 | /* In the case of sock_create_lite(), the sock->sk field is not | |
1740 | * defined yet but it is not a problem as the only users of these | |
1741 | * "lite" PF_INET sockets are functions which do an accept() call | |
1742 | * afterwards so we will label the socket as part of the accept(). */ | |
1743 | sk = sock->sk; | |
1744 | if (sk == NULL) | |
1745 | return 0; | |
1746 | ||
91b1ed0a PM |
1747 | /* We allocate the maximum CIPSO option size here so we are probably |
1748 | * being a little wasteful, but it makes our life _much_ easier later | |
1749 | * on and after all we are only talking about 40 bytes. */ | |
1750 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1751 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
1752 | if (buf == NULL) { | |
1753 | ret_val = -ENOMEM; | |
1754 | goto socket_setattr_failure; | |
1755 | } | |
1756 | ||
446fda4f PM |
1757 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1758 | * really a good assumption to make but since we only support the MAC | |
1759 | * tags right now it is a safe assumption. */ | |
1760 | iter = 0; | |
1761 | do { | |
91b1ed0a | 1762 | memset(buf, 0, buf_len); |
446fda4f PM |
1763 | switch (doi_def->tags[iter]) { |
1764 | case CIPSO_V4_TAG_RBITMAP: | |
1765 | ret_val = cipso_v4_gentag_rbm(doi_def, | |
91b1ed0a PM |
1766 | secattr, |
1767 | &buf[CIPSO_V4_HDR_LEN], | |
1768 | buf_len - CIPSO_V4_HDR_LEN); | |
446fda4f | 1769 | break; |
654bbc2a PM |
1770 | case CIPSO_V4_TAG_ENUM: |
1771 | ret_val = cipso_v4_gentag_enum(doi_def, | |
1772 | secattr, | |
1773 | &buf[CIPSO_V4_HDR_LEN], | |
1774 | buf_len - CIPSO_V4_HDR_LEN); | |
1775 | break; | |
484b3669 PM |
1776 | case CIPSO_V4_TAG_RANGE: |
1777 | ret_val = cipso_v4_gentag_rng(doi_def, | |
1778 | secattr, | |
1779 | &buf[CIPSO_V4_HDR_LEN], | |
1780 | buf_len - CIPSO_V4_HDR_LEN); | |
1781 | break; | |
446fda4f PM |
1782 | default: |
1783 | ret_val = -EPERM; | |
1784 | goto socket_setattr_failure; | |
1785 | } | |
1786 | ||
1787 | iter++; | |
91b1ed0a | 1788 | } while (ret_val < 0 && |
446fda4f PM |
1789 | iter < CIPSO_V4_TAG_MAXCNT && |
1790 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); | |
91b1ed0a | 1791 | if (ret_val < 0) |
446fda4f | 1792 | goto socket_setattr_failure; |
91b1ed0a PM |
1793 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
1794 | buf_len = CIPSO_V4_HDR_LEN + ret_val; | |
446fda4f PM |
1795 | |
1796 | /* We can't use ip_options_get() directly because it makes a call to | |
1797 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
f8687afe PM |
1798 | * we won't always have CAP_NET_RAW even though we _always_ want to |
1799 | * set the IPOPT_CIPSO option. */ | |
446fda4f PM |
1800 | opt_len = (buf_len + 3) & ~3; |
1801 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
1802 | if (opt == NULL) { | |
1803 | ret_val = -ENOMEM; | |
1804 | goto socket_setattr_failure; | |
1805 | } | |
1806 | memcpy(opt->__data, buf, buf_len); | |
1807 | opt->optlen = opt_len; | |
1808 | opt->is_data = 1; | |
f8687afe | 1809 | opt->cipso = sizeof(struct iphdr); |
446fda4f PM |
1810 | kfree(buf); |
1811 | buf = NULL; | |
446fda4f PM |
1812 | |
1813 | sk_inet = inet_sk(sk); | |
1814 | if (sk_inet->is_icsk) { | |
1815 | sk_conn = inet_csk(sk); | |
1816 | if (sk_inet->opt) | |
1817 | sk_conn->icsk_ext_hdr_len -= sk_inet->opt->optlen; | |
1818 | sk_conn->icsk_ext_hdr_len += opt->optlen; | |
1819 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
1820 | } | |
1821 | opt = xchg(&sk_inet->opt, opt); | |
1822 | kfree(opt); | |
1823 | ||
1824 | return 0; | |
1825 | ||
1826 | socket_setattr_failure: | |
1827 | kfree(buf); | |
1828 | kfree(opt); | |
1829 | return ret_val; | |
1830 | } | |
1831 | ||
1832 | /** | |
14a72f53 PM |
1833 | * cipso_v4_sock_getattr - Get the security attributes from a sock |
1834 | * @sk: the sock | |
446fda4f PM |
1835 | * @secattr: the security attributes |
1836 | * | |
1837 | * Description: | |
14a72f53 PM |
1838 | * Query @sk to see if there is a CIPSO option attached to the sock and if |
1839 | * there is return the CIPSO security attributes in @secattr. This function | |
1840 | * requires that @sk be locked, or privately held, but it does not do any | |
1841 | * locking itself. Returns zero on success and negative values on failure. | |
446fda4f PM |
1842 | * |
1843 | */ | |
14a72f53 | 1844 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) |
446fda4f PM |
1845 | { |
1846 | int ret_val = -ENOMSG; | |
446fda4f PM |
1847 | struct inet_sock *sk_inet; |
1848 | unsigned char *cipso_ptr; | |
1849 | u32 doi; | |
1850 | struct cipso_v4_doi *doi_def; | |
1851 | ||
446fda4f PM |
1852 | sk_inet = inet_sk(sk); |
1853 | if (sk_inet->opt == NULL || sk_inet->opt->cipso == 0) | |
14a72f53 | 1854 | return -ENOMSG; |
446fda4f PM |
1855 | cipso_ptr = sk_inet->opt->__data + sk_inet->opt->cipso - |
1856 | sizeof(struct iphdr); | |
1857 | ret_val = cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr); | |
1858 | if (ret_val == 0) | |
14a72f53 | 1859 | return ret_val; |
446fda4f | 1860 | |
714e85be | 1861 | doi = ntohl(*(__be32 *)&cipso_ptr[2]); |
446fda4f | 1862 | rcu_read_lock(); |
9bb5fd2b | 1863 | doi_def = cipso_v4_doi_search(doi); |
446fda4f PM |
1864 | if (doi_def == NULL) { |
1865 | rcu_read_unlock(); | |
14a72f53 | 1866 | return -ENOMSG; |
446fda4f | 1867 | } |
91b1ed0a PM |
1868 | |
1869 | /* XXX - This code assumes only one tag per CIPSO option which isn't | |
1870 | * really a good assumption to make but since we only support the MAC | |
1871 | * tags right now it is a safe assumption. */ | |
446fda4f PM |
1872 | switch (cipso_ptr[6]) { |
1873 | case CIPSO_V4_TAG_RBITMAP: | |
1874 | ret_val = cipso_v4_parsetag_rbm(doi_def, | |
1875 | &cipso_ptr[6], | |
1876 | secattr); | |
1877 | break; | |
654bbc2a PM |
1878 | case CIPSO_V4_TAG_ENUM: |
1879 | ret_val = cipso_v4_parsetag_enum(doi_def, | |
1880 | &cipso_ptr[6], | |
1881 | secattr); | |
1882 | break; | |
484b3669 PM |
1883 | case CIPSO_V4_TAG_RANGE: |
1884 | ret_val = cipso_v4_parsetag_rng(doi_def, | |
1885 | &cipso_ptr[6], | |
1886 | secattr); | |
1887 | break; | |
446fda4f PM |
1888 | } |
1889 | rcu_read_unlock(); | |
1890 | ||
14a72f53 PM |
1891 | return ret_val; |
1892 | } | |
1893 | ||
1894 | /** | |
1895 | * cipso_v4_socket_getattr - Get the security attributes from a socket | |
1896 | * @sock: the socket | |
1897 | * @secattr: the security attributes | |
1898 | * | |
1899 | * Description: | |
1900 | * Query @sock to see if there is a CIPSO option attached to the socket and if | |
1901 | * there is return the CIPSO security attributes in @secattr. Returns zero on | |
1902 | * success and negative values on failure. | |
1903 | * | |
1904 | */ | |
1905 | int cipso_v4_socket_getattr(const struct socket *sock, | |
1906 | struct netlbl_lsm_secattr *secattr) | |
1907 | { | |
1908 | int ret_val; | |
1909 | ||
1910 | lock_sock(sock->sk); | |
1911 | ret_val = cipso_v4_sock_getattr(sock->sk, secattr); | |
1912 | release_sock(sock->sk); | |
1913 | ||
446fda4f PM |
1914 | return ret_val; |
1915 | } | |
1916 | ||
1917 | /** | |
1918 | * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option | |
1919 | * @skb: the packet | |
1920 | * @secattr: the security attributes | |
1921 | * | |
1922 | * Description: | |
1923 | * Parse the given packet's CIPSO option and return the security attributes. | |
1924 | * Returns zero on success and negative values on failure. | |
1925 | * | |
1926 | */ | |
1927 | int cipso_v4_skbuff_getattr(const struct sk_buff *skb, | |
1928 | struct netlbl_lsm_secattr *secattr) | |
1929 | { | |
1930 | int ret_val = -ENOMSG; | |
1931 | unsigned char *cipso_ptr; | |
1932 | u32 doi; | |
1933 | struct cipso_v4_doi *doi_def; | |
1934 | ||
446fda4f PM |
1935 | cipso_ptr = CIPSO_V4_OPTPTR(skb); |
1936 | if (cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr) == 0) | |
1937 | return 0; | |
1938 | ||
714e85be | 1939 | doi = ntohl(*(__be32 *)&cipso_ptr[2]); |
446fda4f | 1940 | rcu_read_lock(); |
9bb5fd2b | 1941 | doi_def = cipso_v4_doi_search(doi); |
446fda4f PM |
1942 | if (doi_def == NULL) |
1943 | goto skbuff_getattr_return; | |
91b1ed0a PM |
1944 | |
1945 | /* XXX - This code assumes only one tag per CIPSO option which isn't | |
1946 | * really a good assumption to make but since we only support the MAC | |
1947 | * tags right now it is a safe assumption. */ | |
446fda4f PM |
1948 | switch (cipso_ptr[6]) { |
1949 | case CIPSO_V4_TAG_RBITMAP: | |
1950 | ret_val = cipso_v4_parsetag_rbm(doi_def, | |
1951 | &cipso_ptr[6], | |
1952 | secattr); | |
1953 | break; | |
654bbc2a PM |
1954 | case CIPSO_V4_TAG_ENUM: |
1955 | ret_val = cipso_v4_parsetag_enum(doi_def, | |
1956 | &cipso_ptr[6], | |
1957 | secattr); | |
1958 | break; | |
38c8947c PM |
1959 | case CIPSO_V4_TAG_RANGE: |
1960 | ret_val = cipso_v4_parsetag_rng(doi_def, | |
1961 | &cipso_ptr[6], | |
1962 | secattr); | |
1963 | break; | |
446fda4f PM |
1964 | } |
1965 | ||
1966 | skbuff_getattr_return: | |
1967 | rcu_read_unlock(); | |
1968 | return ret_val; | |
1969 | } | |
1970 | ||
1971 | /* | |
1972 | * Setup Functions | |
1973 | */ | |
1974 | ||
1975 | /** | |
1976 | * cipso_v4_init - Initialize the CIPSO module | |
1977 | * | |
1978 | * Description: | |
1979 | * Initialize the CIPSO module and prepare it for use. Returns zero on success | |
1980 | * and negative values on failure. | |
1981 | * | |
1982 | */ | |
1983 | static int __init cipso_v4_init(void) | |
1984 | { | |
1985 | int ret_val; | |
1986 | ||
1987 | ret_val = cipso_v4_cache_init(); | |
1988 | if (ret_val != 0) | |
1989 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", | |
1990 | ret_val); | |
1991 | ||
1992 | return 0; | |
1993 | } | |
1994 | ||
1995 | subsys_initcall(cipso_v4_init); |