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 | /* | |
948bf85c | 16 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 |
446fda4f PM |
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 | 47 | #include <asm/bug.h> |
50e5d35c | 48 | #include <asm/unaligned.h> |
446fda4f | 49 | |
446fda4f | 50 | /* List of available DOI definitions */ |
446fda4f PM |
51 | /* XXX - This currently assumes a minimal number of different DOIs in use, |
52 | * if in practice there are a lot of different DOIs this list should | |
53 | * probably be turned into a hash table or something similar so we | |
54 | * can do quick lookups. */ | |
8ce11e6a | 55 | static DEFINE_SPINLOCK(cipso_v4_doi_list_lock); |
1596c97a | 56 | static LIST_HEAD(cipso_v4_doi_list); |
446fda4f PM |
57 | |
58 | /* Label mapping cache */ | |
59 | int cipso_v4_cache_enabled = 1; | |
60 | int cipso_v4_cache_bucketsize = 10; | |
61 | #define CIPSO_V4_CACHE_BUCKETBITS 7 | |
62 | #define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS) | |
63 | #define CIPSO_V4_CACHE_REORDERLIMIT 10 | |
64 | struct cipso_v4_map_cache_bkt { | |
65 | spinlock_t lock; | |
66 | u32 size; | |
67 | struct list_head list; | |
68 | }; | |
69 | struct cipso_v4_map_cache_entry { | |
70 | u32 hash; | |
71 | unsigned char *key; | |
72 | size_t key_len; | |
73 | ||
ffb733c6 | 74 | struct netlbl_lsm_cache *lsm_data; |
446fda4f PM |
75 | |
76 | u32 activity; | |
77 | struct list_head list; | |
78 | }; | |
79 | static struct cipso_v4_map_cache_bkt *cipso_v4_cache = NULL; | |
80 | ||
81 | /* Restricted bitmap (tag #1) flags */ | |
82 | int cipso_v4_rbm_optfmt = 0; | |
83 | int cipso_v4_rbm_strictvalid = 1; | |
84 | ||
f998e8cb PM |
85 | /* |
86 | * Protocol Constants | |
87 | */ | |
88 | ||
89 | /* Maximum size of the CIPSO IP option, derived from the fact that the maximum | |
90 | * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */ | |
91 | #define CIPSO_V4_OPT_LEN_MAX 40 | |
92 | ||
93 | /* Length of the base CIPSO option, this includes the option type (1 byte), the | |
94 | * option length (1 byte), and the DOI (4 bytes). */ | |
95 | #define CIPSO_V4_HDR_LEN 6 | |
96 | ||
97 | /* Base length of the restrictive category bitmap tag (tag #1). */ | |
98 | #define CIPSO_V4_TAG_RBM_BLEN 4 | |
99 | ||
100 | /* Base length of the enumerated category tag (tag #2). */ | |
101 | #define CIPSO_V4_TAG_ENUM_BLEN 4 | |
102 | ||
103 | /* Base length of the ranged categories bitmap tag (tag #5). */ | |
104 | #define CIPSO_V4_TAG_RNG_BLEN 4 | |
105 | /* The maximum number of category ranges permitted in the ranged category tag | |
106 | * (tag #5). You may note that the IETF draft states that the maximum number | |
107 | * of category ranges is 7, but if the low end of the last category range is | |
108 | * zero then it is possibile to fit 8 category ranges because the zero should | |
109 | * be omitted. */ | |
110 | #define CIPSO_V4_TAG_RNG_CAT_MAX 8 | |
111 | ||
15c45f7b PM |
112 | /* Base length of the local tag (non-standard tag). |
113 | * Tag definition (may change between kernel versions) | |
114 | * | |
115 | * 0 8 16 24 32 | |
116 | * +----------+----------+----------+----------+ | |
117 | * | 10000000 | 00000110 | 32-bit secid value | | |
118 | * +----------+----------+----------+----------+ | |
119 | * | in (host byte order)| | |
120 | * +----------+----------+ | |
121 | * | |
122 | */ | |
123 | #define CIPSO_V4_TAG_LOC_BLEN 6 | |
124 | ||
446fda4f PM |
125 | /* |
126 | * Helper Functions | |
127 | */ | |
128 | ||
129 | /** | |
130 | * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit | |
131 | * @bitmap: the bitmap | |
132 | * @bitmap_len: length in bits | |
133 | * @offset: starting offset | |
134 | * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit | |
135 | * | |
136 | * Description: | |
137 | * Starting at @offset, walk the bitmap from left to right until either the | |
138 | * desired bit is found or we reach the end. Return the bit offset, -1 if | |
139 | * not found, or -2 if error. | |
140 | */ | |
141 | static int cipso_v4_bitmap_walk(const unsigned char *bitmap, | |
142 | u32 bitmap_len, | |
143 | u32 offset, | |
144 | u8 state) | |
145 | { | |
146 | u32 bit_spot; | |
147 | u32 byte_offset; | |
148 | unsigned char bitmask; | |
149 | unsigned char byte; | |
150 | ||
151 | /* gcc always rounds to zero when doing integer division */ | |
152 | byte_offset = offset / 8; | |
153 | byte = bitmap[byte_offset]; | |
154 | bit_spot = offset; | |
155 | bitmask = 0x80 >> (offset % 8); | |
156 | ||
157 | while (bit_spot < bitmap_len) { | |
158 | if ((state && (byte & bitmask) == bitmask) || | |
159 | (state == 0 && (byte & bitmask) == 0)) | |
160 | return bit_spot; | |
161 | ||
162 | bit_spot++; | |
163 | bitmask >>= 1; | |
164 | if (bitmask == 0) { | |
165 | byte = bitmap[++byte_offset]; | |
166 | bitmask = 0x80; | |
167 | } | |
168 | } | |
169 | ||
170 | return -1; | |
171 | } | |
172 | ||
173 | /** | |
174 | * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap | |
175 | * @bitmap: the bitmap | |
176 | * @bit: the bit | |
177 | * @state: if non-zero, set the bit (1) else clear the bit (0) | |
178 | * | |
179 | * Description: | |
180 | * Set a single bit in the bitmask. Returns zero on success, negative values | |
181 | * on error. | |
182 | */ | |
183 | static void cipso_v4_bitmap_setbit(unsigned char *bitmap, | |
184 | u32 bit, | |
185 | u8 state) | |
186 | { | |
187 | u32 byte_spot; | |
188 | u8 bitmask; | |
189 | ||
190 | /* gcc always rounds to zero when doing integer division */ | |
191 | byte_spot = bit / 8; | |
192 | bitmask = 0x80 >> (bit % 8); | |
193 | if (state) | |
194 | bitmap[byte_spot] |= bitmask; | |
195 | else | |
196 | bitmap[byte_spot] &= ~bitmask; | |
197 | } | |
198 | ||
446fda4f PM |
199 | /** |
200 | * cipso_v4_cache_entry_free - Frees a cache entry | |
201 | * @entry: the entry to free | |
202 | * | |
203 | * Description: | |
ffb733c6 | 204 | * This function frees the memory associated with a cache entry including the |
205 | * LSM cache data if there are no longer any users, i.e. reference count == 0. | |
446fda4f PM |
206 | * |
207 | */ | |
208 | static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) | |
209 | { | |
ffb733c6 | 210 | if (entry->lsm_data) |
211 | netlbl_secattr_cache_free(entry->lsm_data); | |
446fda4f PM |
212 | kfree(entry->key); |
213 | kfree(entry); | |
214 | } | |
215 | ||
216 | /** | |
217 | * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache | |
218 | * @key: the hash key | |
219 | * @key_len: the length of the key in bytes | |
220 | * | |
221 | * Description: | |
222 | * The CIPSO tag hashing function. Returns a 32-bit hash value. | |
223 | * | |
224 | */ | |
225 | static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) | |
226 | { | |
227 | return jhash(key, key_len, 0); | |
228 | } | |
229 | ||
230 | /* | |
231 | * Label Mapping Cache Functions | |
232 | */ | |
233 | ||
234 | /** | |
235 | * cipso_v4_cache_init - Initialize the CIPSO cache | |
236 | * | |
237 | * Description: | |
238 | * Initializes the CIPSO label mapping cache, this function should be called | |
239 | * before any of the other functions defined in this file. Returns zero on | |
240 | * success, negative values on error. | |
241 | * | |
242 | */ | |
243 | static int cipso_v4_cache_init(void) | |
244 | { | |
245 | u32 iter; | |
246 | ||
247 | cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS, | |
248 | sizeof(struct cipso_v4_map_cache_bkt), | |
249 | GFP_KERNEL); | |
250 | if (cipso_v4_cache == NULL) | |
251 | return -ENOMEM; | |
252 | ||
253 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
254 | spin_lock_init(&cipso_v4_cache[iter].lock); | |
255 | cipso_v4_cache[iter].size = 0; | |
256 | INIT_LIST_HEAD(&cipso_v4_cache[iter].list); | |
257 | } | |
258 | ||
259 | return 0; | |
260 | } | |
261 | ||
262 | /** | |
263 | * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache | |
264 | * | |
265 | * Description: | |
266 | * Invalidates and frees any entries in the CIPSO cache. Returns zero on | |
267 | * success and negative values on failure. | |
268 | * | |
269 | */ | |
270 | void cipso_v4_cache_invalidate(void) | |
271 | { | |
272 | struct cipso_v4_map_cache_entry *entry, *tmp_entry; | |
273 | u32 iter; | |
274 | ||
275 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
609c92fe | 276 | spin_lock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
277 | list_for_each_entry_safe(entry, |
278 | tmp_entry, | |
279 | &cipso_v4_cache[iter].list, list) { | |
280 | list_del(&entry->list); | |
281 | cipso_v4_cache_entry_free(entry); | |
282 | } | |
283 | cipso_v4_cache[iter].size = 0; | |
609c92fe | 284 | spin_unlock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
285 | } |
286 | ||
287 | return; | |
288 | } | |
289 | ||
290 | /** | |
291 | * cipso_v4_cache_check - Check the CIPSO cache for a label mapping | |
292 | * @key: the buffer to check | |
293 | * @key_len: buffer length in bytes | |
294 | * @secattr: the security attribute struct to use | |
295 | * | |
296 | * Description: | |
297 | * This function checks the cache to see if a label mapping already exists for | |
298 | * the given key. If there is a match then the cache is adjusted and the | |
299 | * @secattr struct is populated with the correct LSM security attributes. The | |
300 | * cache is adjusted in the following manner if the entry is not already the | |
301 | * first in the cache bucket: | |
302 | * | |
303 | * 1. The cache entry's activity counter is incremented | |
304 | * 2. The previous (higher ranking) entry's activity counter is decremented | |
305 | * 3. If the difference between the two activity counters is geater than | |
306 | * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped | |
307 | * | |
308 | * Returns zero on success, -ENOENT for a cache miss, and other negative values | |
309 | * on error. | |
310 | * | |
311 | */ | |
312 | static int cipso_v4_cache_check(const unsigned char *key, | |
313 | u32 key_len, | |
314 | struct netlbl_lsm_secattr *secattr) | |
315 | { | |
316 | u32 bkt; | |
317 | struct cipso_v4_map_cache_entry *entry; | |
318 | struct cipso_v4_map_cache_entry *prev_entry = NULL; | |
319 | u32 hash; | |
320 | ||
321 | if (!cipso_v4_cache_enabled) | |
322 | return -ENOENT; | |
323 | ||
324 | hash = cipso_v4_map_cache_hash(key, key_len); | |
5e0f8923 | 325 | bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 326 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
327 | list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) { |
328 | if (entry->hash == hash && | |
329 | entry->key_len == key_len && | |
330 | memcmp(entry->key, key, key_len) == 0) { | |
331 | entry->activity += 1; | |
ffb733c6 | 332 | atomic_inc(&entry->lsm_data->refcount); |
333 | secattr->cache = entry->lsm_data; | |
701a90ba | 334 | secattr->flags |= NETLBL_SECATTR_CACHE; |
16efd454 | 335 | secattr->type = NETLBL_NLTYPE_CIPSOV4; |
446fda4f | 336 | if (prev_entry == NULL) { |
609c92fe | 337 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
338 | return 0; |
339 | } | |
340 | ||
341 | if (prev_entry->activity > 0) | |
342 | prev_entry->activity -= 1; | |
343 | if (entry->activity > prev_entry->activity && | |
344 | entry->activity - prev_entry->activity > | |
345 | CIPSO_V4_CACHE_REORDERLIMIT) { | |
346 | __list_del(entry->list.prev, entry->list.next); | |
347 | __list_add(&entry->list, | |
348 | prev_entry->list.prev, | |
349 | &prev_entry->list); | |
350 | } | |
351 | ||
609c92fe | 352 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
353 | return 0; |
354 | } | |
355 | prev_entry = entry; | |
356 | } | |
609c92fe | 357 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
358 | |
359 | return -ENOENT; | |
360 | } | |
361 | ||
362 | /** | |
363 | * cipso_v4_cache_add - Add an entry to the CIPSO cache | |
364 | * @skb: the packet | |
365 | * @secattr: the packet's security attributes | |
366 | * | |
367 | * Description: | |
368 | * Add a new entry into the CIPSO label mapping cache. Add the new entry to | |
369 | * head of the cache bucket's list, if the cache bucket is out of room remove | |
370 | * the last entry in the list first. It is important to note that there is | |
371 | * currently no checking for duplicate keys. Returns zero on success, | |
372 | * negative values on failure. | |
373 | * | |
374 | */ | |
375 | int cipso_v4_cache_add(const struct sk_buff *skb, | |
376 | const struct netlbl_lsm_secattr *secattr) | |
377 | { | |
378 | int ret_val = -EPERM; | |
379 | u32 bkt; | |
380 | struct cipso_v4_map_cache_entry *entry = NULL; | |
381 | struct cipso_v4_map_cache_entry *old_entry = NULL; | |
382 | unsigned char *cipso_ptr; | |
383 | u32 cipso_ptr_len; | |
384 | ||
385 | if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) | |
386 | return 0; | |
387 | ||
388 | cipso_ptr = CIPSO_V4_OPTPTR(skb); | |
389 | cipso_ptr_len = cipso_ptr[1]; | |
390 | ||
391 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); | |
392 | if (entry == NULL) | |
393 | return -ENOMEM; | |
fac5d731 | 394 | entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC); |
446fda4f PM |
395 | if (entry->key == NULL) { |
396 | ret_val = -ENOMEM; | |
397 | goto cache_add_failure; | |
398 | } | |
446fda4f PM |
399 | entry->key_len = cipso_ptr_len; |
400 | entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len); | |
ffb733c6 | 401 | atomic_inc(&secattr->cache->refcount); |
402 | entry->lsm_data = secattr->cache; | |
446fda4f | 403 | |
5e0f8923 | 404 | bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 405 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
406 | if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { |
407 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
408 | cipso_v4_cache[bkt].size += 1; | |
409 | } else { | |
410 | old_entry = list_entry(cipso_v4_cache[bkt].list.prev, | |
411 | struct cipso_v4_map_cache_entry, list); | |
412 | list_del(&old_entry->list); | |
413 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
414 | cipso_v4_cache_entry_free(old_entry); | |
415 | } | |
609c92fe | 416 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
417 | |
418 | return 0; | |
419 | ||
420 | cache_add_failure: | |
421 | if (entry) | |
422 | cipso_v4_cache_entry_free(entry); | |
423 | return ret_val; | |
424 | } | |
425 | ||
426 | /* | |
427 | * DOI List Functions | |
428 | */ | |
429 | ||
430 | /** | |
431 | * cipso_v4_doi_search - Searches for a DOI definition | |
432 | * @doi: the DOI to search for | |
433 | * | |
434 | * Description: | |
435 | * Search the DOI definition list for a DOI definition with a DOI value that | |
436 | * matches @doi. The caller is responsibile for calling rcu_read_[un]lock(). | |
437 | * Returns a pointer to the DOI definition on success and NULL on failure. | |
438 | */ | |
439 | static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) | |
440 | { | |
441 | struct cipso_v4_doi *iter; | |
442 | ||
443 | list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) | |
b1edeb10 | 444 | if (iter->doi == doi && atomic_read(&iter->refcount)) |
446fda4f PM |
445 | return iter; |
446 | return NULL; | |
447 | } | |
448 | ||
449 | /** | |
450 | * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine | |
451 | * @doi_def: the DOI structure | |
452 | * | |
453 | * Description: | |
454 | * The caller defines a new DOI for use by the CIPSO engine and calls this | |
455 | * function to add it to the list of acceptable domains. The caller must | |
456 | * ensure that the mapping table specified in @doi_def->map meets all of the | |
457 | * requirements of the mapping type (see cipso_ipv4.h for details). Returns | |
458 | * zero on success and non-zero on failure. | |
459 | * | |
460 | */ | |
461 | int cipso_v4_doi_add(struct cipso_v4_doi *doi_def) | |
462 | { | |
6ce61a7c PM |
463 | u32 iter; |
464 | ||
446fda4f PM |
465 | if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN) |
466 | return -EINVAL; | |
6ce61a7c PM |
467 | for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) { |
468 | switch (doi_def->tags[iter]) { | |
469 | case CIPSO_V4_TAG_RBITMAP: | |
470 | break; | |
484b3669 PM |
471 | case CIPSO_V4_TAG_RANGE: |
472 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
473 | return -EINVAL; | |
474 | break; | |
6ce61a7c PM |
475 | case CIPSO_V4_TAG_INVALID: |
476 | if (iter == 0) | |
477 | return -EINVAL; | |
478 | break; | |
654bbc2a PM |
479 | case CIPSO_V4_TAG_ENUM: |
480 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
481 | return -EINVAL; | |
482 | break; | |
15c45f7b PM |
483 | case CIPSO_V4_TAG_LOCAL: |
484 | if (doi_def->type != CIPSO_V4_MAP_LOCAL) | |
485 | return -EINVAL; | |
486 | break; | |
6ce61a7c PM |
487 | default: |
488 | return -EINVAL; | |
489 | } | |
490 | } | |
446fda4f | 491 | |
b1edeb10 | 492 | atomic_set(&doi_def->refcount, 1); |
446fda4f | 493 | INIT_RCU_HEAD(&doi_def->rcu); |
446fda4f | 494 | |
446fda4f PM |
495 | spin_lock(&cipso_v4_doi_list_lock); |
496 | if (cipso_v4_doi_search(doi_def->doi) != NULL) | |
4be2700f | 497 | goto doi_add_failure; |
446fda4f PM |
498 | list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list); |
499 | spin_unlock(&cipso_v4_doi_list_lock); | |
446fda4f PM |
500 | |
501 | return 0; | |
502 | ||
4be2700f | 503 | doi_add_failure: |
446fda4f | 504 | spin_unlock(&cipso_v4_doi_list_lock); |
446fda4f PM |
505 | return -EEXIST; |
506 | } | |
507 | ||
b1edeb10 PM |
508 | /** |
509 | * cipso_v4_doi_free - Frees a DOI definition | |
510 | * @entry: the entry's RCU field | |
511 | * | |
512 | * Description: | |
513 | * This function frees all of the memory associated with a DOI definition. | |
514 | * | |
515 | */ | |
516 | void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) | |
517 | { | |
518 | if (doi_def == NULL) | |
519 | return; | |
520 | ||
521 | switch (doi_def->type) { | |
15c45f7b | 522 | case CIPSO_V4_MAP_TRANS: |
b1edeb10 PM |
523 | kfree(doi_def->map.std->lvl.cipso); |
524 | kfree(doi_def->map.std->lvl.local); | |
525 | kfree(doi_def->map.std->cat.cipso); | |
526 | kfree(doi_def->map.std->cat.local); | |
527 | break; | |
528 | } | |
529 | kfree(doi_def); | |
530 | } | |
531 | ||
532 | /** | |
533 | * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer | |
534 | * @entry: the entry's RCU field | |
535 | * | |
536 | * Description: | |
537 | * This function is designed to be used as a callback to the call_rcu() | |
538 | * function so that the memory allocated to the DOI definition can be released | |
539 | * safely. | |
540 | * | |
541 | */ | |
542 | static void cipso_v4_doi_free_rcu(struct rcu_head *entry) | |
543 | { | |
544 | struct cipso_v4_doi *doi_def; | |
545 | ||
546 | doi_def = container_of(entry, struct cipso_v4_doi, rcu); | |
547 | cipso_v4_doi_free(doi_def); | |
548 | } | |
549 | ||
446fda4f PM |
550 | /** |
551 | * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine | |
552 | * @doi: the DOI value | |
32f50cde | 553 | * @audit_secid: the LSM secid to use in the audit message |
446fda4f PM |
554 | * |
555 | * Description: | |
b1edeb10 PM |
556 | * Removes a DOI definition from the CIPSO engine. The NetLabel routines will |
557 | * be called to release their own LSM domain mappings as well as our own | |
558 | * domain list. Returns zero on success and negative values on failure. | |
446fda4f PM |
559 | * |
560 | */ | |
b1edeb10 | 561 | int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info) |
446fda4f PM |
562 | { |
563 | struct cipso_v4_doi *doi_def; | |
446fda4f | 564 | |
4be2700f PM |
565 | spin_lock(&cipso_v4_doi_list_lock); |
566 | doi_def = cipso_v4_doi_search(doi); | |
b1edeb10 | 567 | if (doi_def == NULL) { |
446fda4f | 568 | spin_unlock(&cipso_v4_doi_list_lock); |
b1edeb10 | 569 | return -ENOENT; |
446fda4f | 570 | } |
b1edeb10 PM |
571 | if (!atomic_dec_and_test(&doi_def->refcount)) { |
572 | spin_unlock(&cipso_v4_doi_list_lock); | |
573 | return -EBUSY; | |
574 | } | |
575 | list_del_rcu(&doi_def->list); | |
4be2700f | 576 | spin_unlock(&cipso_v4_doi_list_lock); |
446fda4f | 577 | |
b1edeb10 PM |
578 | cipso_v4_cache_invalidate(); |
579 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
580 | ||
581 | return 0; | |
446fda4f PM |
582 | } |
583 | ||
584 | /** | |
b1edeb10 | 585 | * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition |
446fda4f PM |
586 | * @doi: the DOI value |
587 | * | |
588 | * Description: | |
589 | * Searches for a valid DOI definition and if one is found it is returned to | |
590 | * the caller. Otherwise NULL is returned. The caller must ensure that | |
b1edeb10 PM |
591 | * rcu_read_lock() is held while accessing the returned definition and the DOI |
592 | * definition reference count is decremented when the caller is done. | |
446fda4f PM |
593 | * |
594 | */ | |
595 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) | |
596 | { | |
b1edeb10 PM |
597 | struct cipso_v4_doi *doi_def; |
598 | ||
599 | rcu_read_lock(); | |
600 | doi_def = cipso_v4_doi_search(doi); | |
601 | if (doi_def == NULL) | |
602 | goto doi_getdef_return; | |
603 | if (!atomic_inc_not_zero(&doi_def->refcount)) | |
604 | doi_def = NULL; | |
605 | ||
606 | doi_getdef_return: | |
607 | rcu_read_unlock(); | |
608 | return doi_def; | |
609 | } | |
610 | ||
611 | /** | |
612 | * cipso_v4_doi_putdef - Releases a reference for the given DOI definition | |
613 | * @doi_def: the DOI definition | |
614 | * | |
615 | * Description: | |
616 | * Releases a DOI definition reference obtained from cipso_v4_doi_getdef(). | |
617 | * | |
618 | */ | |
619 | void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) | |
620 | { | |
621 | if (doi_def == NULL) | |
622 | return; | |
623 | ||
624 | if (!atomic_dec_and_test(&doi_def->refcount)) | |
625 | return; | |
626 | spin_lock(&cipso_v4_doi_list_lock); | |
627 | list_del_rcu(&doi_def->list); | |
628 | spin_unlock(&cipso_v4_doi_list_lock); | |
629 | ||
630 | cipso_v4_cache_invalidate(); | |
631 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
446fda4f PM |
632 | } |
633 | ||
634 | /** | |
fcd48280 PM |
635 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
636 | * @skip_cnt: skip past this number of DOI definitions, updated | |
637 | * @callback: callback for each DOI definition | |
638 | * @cb_arg: argument for the callback function | |
446fda4f PM |
639 | * |
640 | * Description: | |
fcd48280 PM |
641 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
642 | * For each entry call @callback, if @callback returns a negative value stop | |
643 | * 'walking' through the list and return. Updates the value in @skip_cnt upon | |
644 | * return. Returns zero on success, negative values on failure. | |
446fda4f PM |
645 | * |
646 | */ | |
fcd48280 PM |
647 | int cipso_v4_doi_walk(u32 *skip_cnt, |
648 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), | |
649 | void *cb_arg) | |
446fda4f | 650 | { |
fcd48280 | 651 | int ret_val = -ENOENT; |
446fda4f | 652 | u32 doi_cnt = 0; |
fcd48280 | 653 | struct cipso_v4_doi *iter_doi; |
446fda4f | 654 | |
446fda4f | 655 | rcu_read_lock(); |
fcd48280 | 656 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
b1edeb10 | 657 | if (atomic_read(&iter_doi->refcount) > 0) { |
fcd48280 PM |
658 | if (doi_cnt++ < *skip_cnt) |
659 | continue; | |
660 | ret_val = callback(iter_doi, cb_arg); | |
661 | if (ret_val < 0) { | |
662 | doi_cnt--; | |
663 | goto doi_walk_return; | |
446fda4f | 664 | } |
446fda4f | 665 | } |
446fda4f | 666 | |
fcd48280 | 667 | doi_walk_return: |
446fda4f | 668 | rcu_read_unlock(); |
fcd48280 PM |
669 | *skip_cnt = doi_cnt; |
670 | return ret_val; | |
446fda4f PM |
671 | } |
672 | ||
446fda4f PM |
673 | /* |
674 | * Label Mapping Functions | |
675 | */ | |
676 | ||
677 | /** | |
678 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood | |
679 | * @doi_def: the DOI definition | |
680 | * @level: the level to check | |
681 | * | |
682 | * Description: | |
683 | * Checks the given level against the given DOI definition and returns a | |
684 | * negative value if the level does not have a valid mapping and a zero value | |
685 | * if the level is defined by the DOI. | |
686 | * | |
687 | */ | |
688 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) | |
689 | { | |
690 | switch (doi_def->type) { | |
691 | case CIPSO_V4_MAP_PASS: | |
692 | return 0; | |
15c45f7b | 693 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
694 | if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL) |
695 | return 0; | |
696 | break; | |
697 | } | |
698 | ||
699 | return -EFAULT; | |
700 | } | |
701 | ||
702 | /** | |
703 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network | |
704 | * @doi_def: the DOI definition | |
705 | * @host_lvl: the host MLS level | |
706 | * @net_lvl: the network/CIPSO MLS level | |
707 | * | |
708 | * Description: | |
709 | * Perform a label mapping to translate a local MLS level to the correct | |
710 | * CIPSO level using the given DOI definition. Returns zero on success, | |
711 | * negative values otherwise. | |
712 | * | |
713 | */ | |
714 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, | |
715 | u32 host_lvl, | |
716 | u32 *net_lvl) | |
717 | { | |
718 | switch (doi_def->type) { | |
719 | case CIPSO_V4_MAP_PASS: | |
720 | *net_lvl = host_lvl; | |
721 | return 0; | |
15c45f7b | 722 | case CIPSO_V4_MAP_TRANS: |
c6387a86 PM |
723 | if (host_lvl < doi_def->map.std->lvl.local_size && |
724 | doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) { | |
446fda4f PM |
725 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
726 | return 0; | |
727 | } | |
c6387a86 | 728 | return -EPERM; |
446fda4f PM |
729 | } |
730 | ||
731 | return -EINVAL; | |
732 | } | |
733 | ||
734 | /** | |
735 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host | |
736 | * @doi_def: the DOI definition | |
737 | * @net_lvl: the network/CIPSO MLS level | |
738 | * @host_lvl: the host MLS level | |
739 | * | |
740 | * Description: | |
741 | * Perform a label mapping to translate a CIPSO level to the correct local MLS | |
742 | * level using the given DOI definition. Returns zero on success, negative | |
743 | * values otherwise. | |
744 | * | |
745 | */ | |
746 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, | |
747 | u32 net_lvl, | |
748 | u32 *host_lvl) | |
749 | { | |
750 | struct cipso_v4_std_map_tbl *map_tbl; | |
751 | ||
752 | switch (doi_def->type) { | |
753 | case CIPSO_V4_MAP_PASS: | |
754 | *host_lvl = net_lvl; | |
755 | return 0; | |
15c45f7b | 756 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
757 | map_tbl = doi_def->map.std; |
758 | if (net_lvl < map_tbl->lvl.cipso_size && | |
759 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { | |
760 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; | |
761 | return 0; | |
762 | } | |
c6387a86 | 763 | return -EPERM; |
446fda4f PM |
764 | } |
765 | ||
766 | return -EINVAL; | |
767 | } | |
768 | ||
769 | /** | |
770 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid | |
771 | * @doi_def: the DOI definition | |
772 | * @bitmap: category bitmap | |
773 | * @bitmap_len: bitmap length in bytes | |
774 | * | |
775 | * Description: | |
776 | * Checks the given category bitmap against the given DOI definition and | |
777 | * returns a negative value if any of the categories in the bitmap do not have | |
778 | * a valid mapping and a zero value if all of the categories are valid. | |
779 | * | |
780 | */ | |
781 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, | |
782 | const unsigned char *bitmap, | |
783 | u32 bitmap_len) | |
784 | { | |
785 | int cat = -1; | |
786 | u32 bitmap_len_bits = bitmap_len * 8; | |
044a68ed PM |
787 | u32 cipso_cat_size; |
788 | u32 *cipso_array; | |
446fda4f PM |
789 | |
790 | switch (doi_def->type) { | |
791 | case CIPSO_V4_MAP_PASS: | |
792 | return 0; | |
15c45f7b | 793 | case CIPSO_V4_MAP_TRANS: |
044a68ed PM |
794 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
795 | cipso_array = doi_def->map.std->cat.cipso; | |
446fda4f PM |
796 | for (;;) { |
797 | cat = cipso_v4_bitmap_walk(bitmap, | |
798 | bitmap_len_bits, | |
799 | cat + 1, | |
800 | 1); | |
801 | if (cat < 0) | |
802 | break; | |
803 | if (cat >= cipso_cat_size || | |
804 | cipso_array[cat] >= CIPSO_V4_INV_CAT) | |
805 | return -EFAULT; | |
806 | } | |
807 | ||
808 | if (cat == -1) | |
809 | return 0; | |
810 | break; | |
811 | } | |
812 | ||
813 | return -EFAULT; | |
814 | } | |
815 | ||
816 | /** | |
817 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network | |
818 | * @doi_def: the DOI definition | |
02752760 | 819 | * @secattr: the security attributes |
446fda4f PM |
820 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
821 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
822 | * | |
823 | * Description: | |
824 | * Perform a label mapping to translate a local MLS category bitmap to the | |
825 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum | |
826 | * size in bytes of the network bitmap on success, negative values otherwise. | |
827 | * | |
828 | */ | |
829 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, | |
02752760 | 830 | const struct netlbl_lsm_secattr *secattr, |
446fda4f PM |
831 | unsigned char *net_cat, |
832 | u32 net_cat_len) | |
833 | { | |
834 | int host_spot = -1; | |
02752760 | 835 | u32 net_spot = CIPSO_V4_INV_CAT; |
446fda4f | 836 | u32 net_spot_max = 0; |
446fda4f | 837 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
838 | u32 host_cat_size = 0; |
839 | u32 *host_cat_array = NULL; | |
446fda4f | 840 | |
15c45f7b | 841 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
842 | host_cat_size = doi_def->map.std->cat.local_size; |
843 | host_cat_array = doi_def->map.std->cat.local; | |
02752760 PM |
844 | } |
845 | ||
846 | for (;;) { | |
16efd454 | 847 | host_spot = netlbl_secattr_catmap_walk(secattr->attr.mls.cat, |
02752760 PM |
848 | host_spot + 1); |
849 | if (host_spot < 0) | |
850 | break; | |
851 | ||
852 | switch (doi_def->type) { | |
853 | case CIPSO_V4_MAP_PASS: | |
854 | net_spot = host_spot; | |
855 | break; | |
15c45f7b | 856 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
857 | if (host_spot >= host_cat_size) |
858 | return -EPERM; | |
446fda4f | 859 | net_spot = host_cat_array[host_spot]; |
9fade4bf PM |
860 | if (net_spot >= CIPSO_V4_INV_CAT) |
861 | return -EPERM; | |
02752760 | 862 | break; |
446fda4f | 863 | } |
02752760 PM |
864 | if (net_spot >= net_clen_bits) |
865 | return -ENOSPC; | |
866 | cipso_v4_bitmap_setbit(net_cat, net_spot, 1); | |
446fda4f | 867 | |
02752760 PM |
868 | if (net_spot > net_spot_max) |
869 | net_spot_max = net_spot; | |
446fda4f PM |
870 | } |
871 | ||
02752760 PM |
872 | if (++net_spot_max % 8) |
873 | return net_spot_max / 8 + 1; | |
874 | return net_spot_max / 8; | |
446fda4f PM |
875 | } |
876 | ||
877 | /** | |
878 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host | |
879 | * @doi_def: the DOI definition | |
880 | * @net_cat: the category bitmap in network/CIPSO format | |
881 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
02752760 | 882 | * @secattr: the security attributes |
446fda4f PM |
883 | * |
884 | * Description: | |
885 | * Perform a label mapping to translate a CIPSO bitmap to the correct local | |
02752760 PM |
886 | * MLS category bitmap using the given DOI definition. Returns zero on |
887 | * success, negative values on failure. | |
446fda4f PM |
888 | * |
889 | */ | |
890 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, | |
891 | const unsigned char *net_cat, | |
892 | u32 net_cat_len, | |
02752760 | 893 | struct netlbl_lsm_secattr *secattr) |
446fda4f | 894 | { |
02752760 | 895 | int ret_val; |
446fda4f | 896 | int net_spot = -1; |
02752760 | 897 | u32 host_spot = CIPSO_V4_INV_CAT; |
446fda4f | 898 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
899 | u32 net_cat_size = 0; |
900 | u32 *net_cat_array = NULL; | |
446fda4f | 901 | |
15c45f7b | 902 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
903 | net_cat_size = doi_def->map.std->cat.cipso_size; |
904 | net_cat_array = doi_def->map.std->cat.cipso; | |
02752760 | 905 | } |
446fda4f | 906 | |
02752760 PM |
907 | for (;;) { |
908 | net_spot = cipso_v4_bitmap_walk(net_cat, | |
909 | net_clen_bits, | |
910 | net_spot + 1, | |
911 | 1); | |
912 | if (net_spot < 0) { | |
913 | if (net_spot == -2) | |
914 | return -EFAULT; | |
915 | return 0; | |
916 | } | |
917 | ||
918 | switch (doi_def->type) { | |
919 | case CIPSO_V4_MAP_PASS: | |
920 | host_spot = net_spot; | |
921 | break; | |
15c45f7b | 922 | case CIPSO_V4_MAP_TRANS: |
02752760 PM |
923 | if (net_spot >= net_cat_size) |
924 | return -EPERM; | |
446fda4f | 925 | host_spot = net_cat_array[net_spot]; |
9fade4bf PM |
926 | if (host_spot >= CIPSO_V4_INV_CAT) |
927 | return -EPERM; | |
02752760 | 928 | break; |
446fda4f | 929 | } |
16efd454 | 930 | ret_val = netlbl_secattr_catmap_setbit(secattr->attr.mls.cat, |
02752760 PM |
931 | host_spot, |
932 | GFP_ATOMIC); | |
933 | if (ret_val != 0) | |
934 | return ret_val; | |
446fda4f PM |
935 | } |
936 | ||
937 | return -EINVAL; | |
938 | } | |
939 | ||
654bbc2a PM |
940 | /** |
941 | * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid | |
942 | * @doi_def: the DOI definition | |
943 | * @enumcat: category list | |
944 | * @enumcat_len: length of the category list in bytes | |
945 | * | |
946 | * Description: | |
947 | * Checks the given categories against the given DOI definition and returns a | |
948 | * negative value if any of the categories do not have a valid mapping and a | |
949 | * zero value if all of the categories are valid. | |
950 | * | |
951 | */ | |
952 | static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, | |
953 | const unsigned char *enumcat, | |
954 | u32 enumcat_len) | |
955 | { | |
956 | u16 cat; | |
957 | int cat_prev = -1; | |
958 | u32 iter; | |
959 | ||
960 | if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01) | |
961 | return -EFAULT; | |
962 | ||
963 | for (iter = 0; iter < enumcat_len; iter += 2) { | |
d3e2ce3b | 964 | cat = get_unaligned_be16(&enumcat[iter]); |
654bbc2a PM |
965 | if (cat <= cat_prev) |
966 | return -EFAULT; | |
967 | cat_prev = cat; | |
968 | } | |
969 | ||
970 | return 0; | |
971 | } | |
972 | ||
973 | /** | |
974 | * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network | |
975 | * @doi_def: the DOI definition | |
976 | * @secattr: the security attributes | |
977 | * @net_cat: the zero'd out category list in network/CIPSO format | |
978 | * @net_cat_len: the length of the CIPSO category list in bytes | |
979 | * | |
980 | * Description: | |
981 | * Perform a label mapping to translate a local MLS category bitmap to the | |
982 | * correct CIPSO category list using the given DOI definition. Returns the | |
983 | * size in bytes of the network category bitmap on success, negative values | |
984 | * otherwise. | |
985 | * | |
986 | */ | |
987 | static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, | |
988 | const struct netlbl_lsm_secattr *secattr, | |
989 | unsigned char *net_cat, | |
990 | u32 net_cat_len) | |
991 | { | |
992 | int cat = -1; | |
993 | u32 cat_iter = 0; | |
994 | ||
995 | for (;;) { | |
16efd454 PM |
996 | cat = netlbl_secattr_catmap_walk(secattr->attr.mls.cat, |
997 | cat + 1); | |
654bbc2a PM |
998 | if (cat < 0) |
999 | break; | |
1000 | if ((cat_iter + 2) > net_cat_len) | |
1001 | return -ENOSPC; | |
1002 | ||
1003 | *((__be16 *)&net_cat[cat_iter]) = htons(cat); | |
1004 | cat_iter += 2; | |
1005 | } | |
1006 | ||
1007 | return cat_iter; | |
1008 | } | |
1009 | ||
1010 | /** | |
1011 | * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host | |
1012 | * @doi_def: the DOI definition | |
1013 | * @net_cat: the category list in network/CIPSO format | |
1014 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1015 | * @secattr: the security attributes | |
1016 | * | |
1017 | * Description: | |
1018 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1019 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1020 | * success, negative values on failure. | |
1021 | * | |
1022 | */ | |
1023 | static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, | |
1024 | const unsigned char *net_cat, | |
1025 | u32 net_cat_len, | |
1026 | struct netlbl_lsm_secattr *secattr) | |
1027 | { | |
1028 | int ret_val; | |
1029 | u32 iter; | |
1030 | ||
1031 | for (iter = 0; iter < net_cat_len; iter += 2) { | |
16efd454 | 1032 | ret_val = netlbl_secattr_catmap_setbit(secattr->attr.mls.cat, |
d3e2ce3b | 1033 | get_unaligned_be16(&net_cat[iter]), |
50e5d35c | 1034 | GFP_ATOMIC); |
654bbc2a PM |
1035 | if (ret_val != 0) |
1036 | return ret_val; | |
1037 | } | |
1038 | ||
1039 | return 0; | |
1040 | } | |
1041 | ||
484b3669 PM |
1042 | /** |
1043 | * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid | |
1044 | * @doi_def: the DOI definition | |
1045 | * @rngcat: category list | |
1046 | * @rngcat_len: length of the category list in bytes | |
1047 | * | |
1048 | * Description: | |
1049 | * Checks the given categories against the given DOI definition and returns a | |
1050 | * negative value if any of the categories do not have a valid mapping and a | |
1051 | * zero value if all of the categories are valid. | |
1052 | * | |
1053 | */ | |
1054 | static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, | |
1055 | const unsigned char *rngcat, | |
1056 | u32 rngcat_len) | |
1057 | { | |
1058 | u16 cat_high; | |
1059 | u16 cat_low; | |
1060 | u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1; | |
1061 | u32 iter; | |
1062 | ||
1063 | if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01) | |
1064 | return -EFAULT; | |
1065 | ||
1066 | for (iter = 0; iter < rngcat_len; iter += 4) { | |
d3e2ce3b | 1067 | cat_high = get_unaligned_be16(&rngcat[iter]); |
484b3669 | 1068 | if ((iter + 4) <= rngcat_len) |
d3e2ce3b | 1069 | cat_low = get_unaligned_be16(&rngcat[iter + 2]); |
484b3669 PM |
1070 | else |
1071 | cat_low = 0; | |
1072 | ||
1073 | if (cat_high > cat_prev) | |
1074 | return -EFAULT; | |
1075 | ||
1076 | cat_prev = cat_low; | |
1077 | } | |
1078 | ||
1079 | return 0; | |
1080 | } | |
1081 | ||
1082 | /** | |
1083 | * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network | |
1084 | * @doi_def: the DOI definition | |
1085 | * @secattr: the security attributes | |
1086 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1087 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1088 | * | |
1089 | * Description: | |
1090 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1091 | * correct CIPSO category list using the given DOI definition. Returns the | |
1092 | * size in bytes of the network category bitmap on success, negative values | |
1093 | * otherwise. | |
1094 | * | |
1095 | */ | |
1096 | static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, | |
1097 | const struct netlbl_lsm_secattr *secattr, | |
1098 | unsigned char *net_cat, | |
1099 | u32 net_cat_len) | |
1100 | { | |
484b3669 | 1101 | int iter = -1; |
f998e8cb | 1102 | u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2]; |
484b3669 PM |
1103 | u32 array_cnt = 0; |
1104 | u32 cat_size = 0; | |
1105 | ||
f998e8cb | 1106 | /* make sure we don't overflow the 'array[]' variable */ |
128c6b6c PM |
1107 | if (net_cat_len > |
1108 | (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN)) | |
1109 | return -ENOSPC; | |
484b3669 PM |
1110 | |
1111 | for (;;) { | |
16efd454 PM |
1112 | iter = netlbl_secattr_catmap_walk(secattr->attr.mls.cat, |
1113 | iter + 1); | |
484b3669 PM |
1114 | if (iter < 0) |
1115 | break; | |
1116 | cat_size += (iter == 0 ? 0 : sizeof(u16)); | |
1117 | if (cat_size > net_cat_len) | |
1118 | return -ENOSPC; | |
1119 | array[array_cnt++] = iter; | |
1120 | ||
16efd454 PM |
1121 | iter = netlbl_secattr_catmap_walk_rng(secattr->attr.mls.cat, |
1122 | iter); | |
484b3669 PM |
1123 | if (iter < 0) |
1124 | return -EFAULT; | |
1125 | cat_size += sizeof(u16); | |
1126 | if (cat_size > net_cat_len) | |
1127 | return -ENOSPC; | |
1128 | array[array_cnt++] = iter; | |
1129 | } | |
1130 | ||
1131 | for (iter = 0; array_cnt > 0;) { | |
1132 | *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]); | |
1133 | iter += 2; | |
1134 | array_cnt--; | |
1135 | if (array[array_cnt] != 0) { | |
1136 | *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]); | |
1137 | iter += 2; | |
1138 | } | |
1139 | } | |
1140 | ||
1141 | return cat_size; | |
1142 | } | |
1143 | ||
1144 | /** | |
1145 | * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host | |
1146 | * @doi_def: the DOI definition | |
1147 | * @net_cat: the category list in network/CIPSO format | |
1148 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1149 | * @secattr: the security attributes | |
1150 | * | |
1151 | * Description: | |
1152 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1153 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1154 | * success, negative values on failure. | |
1155 | * | |
1156 | */ | |
1157 | static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, | |
1158 | const unsigned char *net_cat, | |
1159 | u32 net_cat_len, | |
1160 | struct netlbl_lsm_secattr *secattr) | |
1161 | { | |
1162 | int ret_val; | |
1163 | u32 net_iter; | |
1164 | u16 cat_low; | |
1165 | u16 cat_high; | |
1166 | ||
132adf54 | 1167 | for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) { |
d3e2ce3b | 1168 | cat_high = get_unaligned_be16(&net_cat[net_iter]); |
484b3669 | 1169 | if ((net_iter + 4) <= net_cat_len) |
d3e2ce3b | 1170 | cat_low = get_unaligned_be16(&net_cat[net_iter + 2]); |
484b3669 PM |
1171 | else |
1172 | cat_low = 0; | |
1173 | ||
16efd454 | 1174 | ret_val = netlbl_secattr_catmap_setrng(secattr->attr.mls.cat, |
484b3669 PM |
1175 | cat_low, |
1176 | cat_high, | |
1177 | GFP_ATOMIC); | |
1178 | if (ret_val != 0) | |
1179 | return ret_val; | |
1180 | } | |
1181 | ||
1182 | return 0; | |
1183 | } | |
1184 | ||
446fda4f PM |
1185 | /* |
1186 | * Protocol Handling Functions | |
1187 | */ | |
1188 | ||
446fda4f PM |
1189 | /** |
1190 | * cipso_v4_gentag_hdr - Generate a CIPSO option header | |
1191 | * @doi_def: the DOI definition | |
91b1ed0a | 1192 | * @len: the total tag length in bytes, not including this header |
446fda4f PM |
1193 | * @buf: the CIPSO option buffer |
1194 | * | |
1195 | * Description: | |
91b1ed0a | 1196 | * Write a CIPSO header into the beginning of @buffer. |
446fda4f PM |
1197 | * |
1198 | */ | |
91b1ed0a PM |
1199 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
1200 | unsigned char *buf, | |
1201 | u32 len) | |
446fda4f | 1202 | { |
446fda4f PM |
1203 | buf[0] = IPOPT_CIPSO; |
1204 | buf[1] = CIPSO_V4_HDR_LEN + len; | |
714e85be | 1205 | *(__be32 *)&buf[2] = htonl(doi_def->doi); |
446fda4f PM |
1206 | } |
1207 | ||
446fda4f PM |
1208 | /** |
1209 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) | |
1210 | * @doi_def: the DOI definition | |
1211 | * @secattr: the security attributes | |
1212 | * @buffer: the option buffer | |
1213 | * @buffer_len: length of buffer in bytes | |
1214 | * | |
1215 | * Description: | |
1216 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The | |
1217 | * actual buffer length may be larger than the indicated size due to | |
91b1ed0a PM |
1218 | * translation between host and network category bitmaps. Returns the size of |
1219 | * the tag on success, negative values on failure. | |
446fda4f PM |
1220 | * |
1221 | */ | |
1222 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, | |
1223 | const struct netlbl_lsm_secattr *secattr, | |
91b1ed0a PM |
1224 | unsigned char *buffer, |
1225 | u32 buffer_len) | |
446fda4f | 1226 | { |
701a90ba | 1227 | int ret_val; |
91b1ed0a | 1228 | u32 tag_len; |
446fda4f PM |
1229 | u32 level; |
1230 | ||
701a90ba PM |
1231 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
1232 | return -EPERM; | |
1233 | ||
16efd454 PM |
1234 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1235 | secattr->attr.mls.lvl, | |
1236 | &level); | |
91b1ed0a PM |
1237 | if (ret_val != 0) |
1238 | return ret_val; | |
446fda4f | 1239 | |
91b1ed0a | 1240 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
446fda4f | 1241 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
02752760 | 1242 | secattr, |
91b1ed0a PM |
1243 | &buffer[4], |
1244 | buffer_len - 4); | |
446fda4f | 1245 | if (ret_val < 0) |
91b1ed0a | 1246 | return ret_val; |
446fda4f PM |
1247 | |
1248 | /* This will send packets using the "optimized" format when | |
1249 | * possibile as specified in section 3.4.2.6 of the | |
1250 | * CIPSO draft. */ | |
701a90ba | 1251 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
91b1ed0a | 1252 | tag_len = 14; |
701a90ba | 1253 | else |
91b1ed0a PM |
1254 | tag_len = 4 + ret_val; |
1255 | } else | |
1256 | tag_len = 4; | |
446fda4f | 1257 | |
15c45f7b | 1258 | buffer[0] = CIPSO_V4_TAG_RBITMAP; |
91b1ed0a PM |
1259 | buffer[1] = tag_len; |
1260 | buffer[3] = level; | |
446fda4f | 1261 | |
91b1ed0a | 1262 | return tag_len; |
446fda4f PM |
1263 | } |
1264 | ||
1265 | /** | |
1266 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag | |
1267 | * @doi_def: the DOI definition | |
1268 | * @tag: the CIPSO tag | |
1269 | * @secattr: the security attributes | |
1270 | * | |
1271 | * Description: | |
1272 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security | |
1273 | * attributes in @secattr. Return zero on success, negatives values on | |
1274 | * failure. | |
1275 | * | |
1276 | */ | |
1277 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, | |
1278 | const unsigned char *tag, | |
1279 | struct netlbl_lsm_secattr *secattr) | |
1280 | { | |
1281 | int ret_val; | |
1282 | u8 tag_len = tag[1]; | |
1283 | u32 level; | |
1284 | ||
1285 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1286 | if (ret_val != 0) | |
1287 | return ret_val; | |
16efd454 | 1288 | secattr->attr.mls.lvl = level; |
701a90ba | 1289 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
446fda4f PM |
1290 | |
1291 | if (tag_len > 4) { | |
16efd454 PM |
1292 | secattr->attr.mls.cat = |
1293 | netlbl_secattr_catmap_alloc(GFP_ATOMIC); | |
1294 | if (secattr->attr.mls.cat == NULL) | |
446fda4f PM |
1295 | return -ENOMEM; |
1296 | ||
1297 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, | |
1298 | &tag[4], | |
1299 | tag_len - 4, | |
02752760 PM |
1300 | secattr); |
1301 | if (ret_val != 0) { | |
16efd454 | 1302 | netlbl_secattr_catmap_free(secattr->attr.mls.cat); |
446fda4f PM |
1303 | return ret_val; |
1304 | } | |
02752760 PM |
1305 | |
1306 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
446fda4f PM |
1307 | } |
1308 | ||
1309 | return 0; | |
1310 | } | |
1311 | ||
654bbc2a PM |
1312 | /** |
1313 | * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) | |
1314 | * @doi_def: the DOI definition | |
1315 | * @secattr: the security attributes | |
1316 | * @buffer: the option buffer | |
1317 | * @buffer_len: length of buffer in bytes | |
1318 | * | |
1319 | * Description: | |
1320 | * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the | |
1321 | * size of the tag on success, negative values on failure. | |
1322 | * | |
1323 | */ | |
1324 | static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, | |
1325 | const struct netlbl_lsm_secattr *secattr, | |
1326 | unsigned char *buffer, | |
1327 | u32 buffer_len) | |
1328 | { | |
1329 | int ret_val; | |
1330 | u32 tag_len; | |
1331 | u32 level; | |
1332 | ||
1333 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1334 | return -EPERM; | |
1335 | ||
16efd454 PM |
1336 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1337 | secattr->attr.mls.lvl, | |
1338 | &level); | |
654bbc2a PM |
1339 | if (ret_val != 0) |
1340 | return ret_val; | |
1341 | ||
1342 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1343 | ret_val = cipso_v4_map_cat_enum_hton(doi_def, | |
1344 | secattr, | |
1345 | &buffer[4], | |
1346 | buffer_len - 4); | |
1347 | if (ret_val < 0) | |
1348 | return ret_val; | |
1349 | ||
1350 | tag_len = 4 + ret_val; | |
1351 | } else | |
1352 | tag_len = 4; | |
1353 | ||
15c45f7b | 1354 | buffer[0] = CIPSO_V4_TAG_ENUM; |
654bbc2a PM |
1355 | buffer[1] = tag_len; |
1356 | buffer[3] = level; | |
1357 | ||
1358 | return tag_len; | |
1359 | } | |
1360 | ||
1361 | /** | |
1362 | * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag | |
1363 | * @doi_def: the DOI definition | |
1364 | * @tag: the CIPSO tag | |
1365 | * @secattr: the security attributes | |
1366 | * | |
1367 | * Description: | |
1368 | * Parse a CIPSO enumerated tag (tag type #2) and return the security | |
1369 | * attributes in @secattr. Return zero on success, negatives values on | |
1370 | * failure. | |
1371 | * | |
1372 | */ | |
1373 | static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, | |
1374 | const unsigned char *tag, | |
1375 | struct netlbl_lsm_secattr *secattr) | |
1376 | { | |
1377 | int ret_val; | |
1378 | u8 tag_len = tag[1]; | |
1379 | u32 level; | |
1380 | ||
1381 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1382 | if (ret_val != 0) | |
1383 | return ret_val; | |
16efd454 | 1384 | secattr->attr.mls.lvl = level; |
654bbc2a PM |
1385 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1386 | ||
1387 | if (tag_len > 4) { | |
16efd454 PM |
1388 | secattr->attr.mls.cat = |
1389 | netlbl_secattr_catmap_alloc(GFP_ATOMIC); | |
1390 | if (secattr->attr.mls.cat == NULL) | |
654bbc2a PM |
1391 | return -ENOMEM; |
1392 | ||
1393 | ret_val = cipso_v4_map_cat_enum_ntoh(doi_def, | |
1394 | &tag[4], | |
1395 | tag_len - 4, | |
1396 | secattr); | |
1397 | if (ret_val != 0) { | |
16efd454 | 1398 | netlbl_secattr_catmap_free(secattr->attr.mls.cat); |
654bbc2a PM |
1399 | return ret_val; |
1400 | } | |
1401 | ||
1402 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1403 | } | |
1404 | ||
1405 | return 0; | |
1406 | } | |
1407 | ||
484b3669 PM |
1408 | /** |
1409 | * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) | |
1410 | * @doi_def: the DOI definition | |
1411 | * @secattr: the security attributes | |
1412 | * @buffer: the option buffer | |
1413 | * @buffer_len: length of buffer in bytes | |
1414 | * | |
1415 | * Description: | |
1416 | * Generate a CIPSO option using the ranged tag, tag type #5. Returns the | |
1417 | * size of the tag on success, negative values on failure. | |
1418 | * | |
1419 | */ | |
1420 | static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, | |
1421 | const struct netlbl_lsm_secattr *secattr, | |
1422 | unsigned char *buffer, | |
1423 | u32 buffer_len) | |
1424 | { | |
1425 | int ret_val; | |
1426 | u32 tag_len; | |
1427 | u32 level; | |
1428 | ||
1429 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1430 | return -EPERM; | |
1431 | ||
16efd454 PM |
1432 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1433 | secattr->attr.mls.lvl, | |
1434 | &level); | |
484b3669 PM |
1435 | if (ret_val != 0) |
1436 | return ret_val; | |
1437 | ||
1438 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1439 | ret_val = cipso_v4_map_cat_rng_hton(doi_def, | |
1440 | secattr, | |
1441 | &buffer[4], | |
1442 | buffer_len - 4); | |
1443 | if (ret_val < 0) | |
1444 | return ret_val; | |
1445 | ||
1446 | tag_len = 4 + ret_val; | |
1447 | } else | |
1448 | tag_len = 4; | |
1449 | ||
15c45f7b | 1450 | buffer[0] = CIPSO_V4_TAG_RANGE; |
484b3669 PM |
1451 | buffer[1] = tag_len; |
1452 | buffer[3] = level; | |
1453 | ||
1454 | return tag_len; | |
1455 | } | |
1456 | ||
1457 | /** | |
1458 | * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag | |
1459 | * @doi_def: the DOI definition | |
1460 | * @tag: the CIPSO tag | |
1461 | * @secattr: the security attributes | |
1462 | * | |
1463 | * Description: | |
1464 | * Parse a CIPSO ranged tag (tag type #5) and return the security attributes | |
1465 | * in @secattr. Return zero on success, negatives values on failure. | |
1466 | * | |
1467 | */ | |
1468 | static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, | |
1469 | const unsigned char *tag, | |
1470 | struct netlbl_lsm_secattr *secattr) | |
1471 | { | |
1472 | int ret_val; | |
1473 | u8 tag_len = tag[1]; | |
1474 | u32 level; | |
1475 | ||
1476 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1477 | if (ret_val != 0) | |
1478 | return ret_val; | |
16efd454 | 1479 | secattr->attr.mls.lvl = level; |
484b3669 PM |
1480 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1481 | ||
1482 | if (tag_len > 4) { | |
16efd454 PM |
1483 | secattr->attr.mls.cat = |
1484 | netlbl_secattr_catmap_alloc(GFP_ATOMIC); | |
1485 | if (secattr->attr.mls.cat == NULL) | |
484b3669 PM |
1486 | return -ENOMEM; |
1487 | ||
1488 | ret_val = cipso_v4_map_cat_rng_ntoh(doi_def, | |
1489 | &tag[4], | |
1490 | tag_len - 4, | |
1491 | secattr); | |
1492 | if (ret_val != 0) { | |
16efd454 | 1493 | netlbl_secattr_catmap_free(secattr->attr.mls.cat); |
484b3669 PM |
1494 | return ret_val; |
1495 | } | |
1496 | ||
1497 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1498 | } | |
1499 | ||
1500 | return 0; | |
1501 | } | |
1502 | ||
15c45f7b PM |
1503 | /** |
1504 | * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard) | |
1505 | * @doi_def: the DOI definition | |
1506 | * @secattr: the security attributes | |
1507 | * @buffer: the option buffer | |
1508 | * @buffer_len: length of buffer in bytes | |
1509 | * | |
1510 | * Description: | |
1511 | * Generate a CIPSO option using the local tag. Returns the size of the tag | |
1512 | * on success, negative values on failure. | |
1513 | * | |
1514 | */ | |
1515 | static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def, | |
1516 | const struct netlbl_lsm_secattr *secattr, | |
1517 | unsigned char *buffer, | |
1518 | u32 buffer_len) | |
1519 | { | |
1520 | if (!(secattr->flags & NETLBL_SECATTR_SECID)) | |
1521 | return -EPERM; | |
1522 | ||
1523 | buffer[0] = CIPSO_V4_TAG_LOCAL; | |
1524 | buffer[1] = CIPSO_V4_TAG_LOC_BLEN; | |
1525 | *(u32 *)&buffer[2] = secattr->attr.secid; | |
1526 | ||
1527 | return CIPSO_V4_TAG_LOC_BLEN; | |
1528 | } | |
1529 | ||
1530 | /** | |
1531 | * cipso_v4_parsetag_loc - Parse a CIPSO local tag | |
1532 | * @doi_def: the DOI definition | |
1533 | * @tag: the CIPSO tag | |
1534 | * @secattr: the security attributes | |
1535 | * | |
1536 | * Description: | |
1537 | * Parse a CIPSO local tag and return the security attributes in @secattr. | |
1538 | * Return zero on success, negatives values on failure. | |
1539 | * | |
1540 | */ | |
1541 | static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def, | |
1542 | const unsigned char *tag, | |
1543 | struct netlbl_lsm_secattr *secattr) | |
1544 | { | |
1545 | secattr->attr.secid = *(u32 *)&tag[2]; | |
1546 | secattr->flags |= NETLBL_SECATTR_SECID; | |
1547 | ||
1548 | return 0; | |
1549 | } | |
1550 | ||
446fda4f PM |
1551 | /** |
1552 | * cipso_v4_validate - Validate a CIPSO option | |
1553 | * @option: the start of the option, on error it is set to point to the error | |
1554 | * | |
1555 | * Description: | |
1556 | * This routine is called to validate a CIPSO option, it checks all of the | |
1557 | * fields to ensure that they are at least valid, see the draft snippet below | |
1558 | * for details. If the option is valid then a zero value is returned and | |
1559 | * the value of @option is unchanged. If the option is invalid then a | |
1560 | * non-zero value is returned and @option is adjusted to point to the | |
1561 | * offending portion of the option. From the IETF draft ... | |
1562 | * | |
1563 | * "If any field within the CIPSO options, such as the DOI identifier, is not | |
1564 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' | |
1565 | * (type 12) is generated and returned. The ICMP code field is set to 'bad | |
1566 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field | |
1567 | * that is unrecognized." | |
1568 | * | |
1569 | */ | |
15c45f7b | 1570 | int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) |
446fda4f PM |
1571 | { |
1572 | unsigned char *opt = *option; | |
1573 | unsigned char *tag; | |
1574 | unsigned char opt_iter; | |
1575 | unsigned char err_offset = 0; | |
1576 | u8 opt_len; | |
1577 | u8 tag_len; | |
1578 | struct cipso_v4_doi *doi_def = NULL; | |
1579 | u32 tag_iter; | |
1580 | ||
1581 | /* caller already checks for length values that are too large */ | |
1582 | opt_len = opt[1]; | |
1583 | if (opt_len < 8) { | |
1584 | err_offset = 1; | |
1585 | goto validate_return; | |
1586 | } | |
1587 | ||
1588 | rcu_read_lock(); | |
d3e2ce3b | 1589 | doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2])); |
446fda4f PM |
1590 | if (doi_def == NULL) { |
1591 | err_offset = 2; | |
1592 | goto validate_return_locked; | |
1593 | } | |
1594 | ||
15c45f7b | 1595 | opt_iter = CIPSO_V4_HDR_LEN; |
446fda4f PM |
1596 | tag = opt + opt_iter; |
1597 | while (opt_iter < opt_len) { | |
1598 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) | |
1599 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || | |
1600 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { | |
1601 | err_offset = opt_iter; | |
1602 | goto validate_return_locked; | |
1603 | } | |
1604 | ||
1605 | tag_len = tag[1]; | |
1606 | if (tag_len > (opt_len - opt_iter)) { | |
1607 | err_offset = opt_iter + 1; | |
1608 | goto validate_return_locked; | |
1609 | } | |
1610 | ||
1611 | switch (tag[0]) { | |
1612 | case CIPSO_V4_TAG_RBITMAP: | |
15c45f7b | 1613 | if (tag_len < CIPSO_V4_TAG_RBM_BLEN) { |
446fda4f PM |
1614 | err_offset = opt_iter + 1; |
1615 | goto validate_return_locked; | |
1616 | } | |
1617 | ||
1618 | /* We are already going to do all the verification | |
1619 | * necessary at the socket layer so from our point of | |
1620 | * view it is safe to turn these checks off (and less | |
1621 | * work), however, the CIPSO draft says we should do | |
1622 | * all the CIPSO validations here but it doesn't | |
1623 | * really specify _exactly_ what we need to validate | |
1624 | * ... so, just make it a sysctl tunable. */ | |
1625 | if (cipso_v4_rbm_strictvalid) { | |
1626 | if (cipso_v4_map_lvl_valid(doi_def, | |
1627 | tag[3]) < 0) { | |
1628 | err_offset = opt_iter + 3; | |
1629 | goto validate_return_locked; | |
1630 | } | |
15c45f7b | 1631 | if (tag_len > CIPSO_V4_TAG_RBM_BLEN && |
446fda4f PM |
1632 | cipso_v4_map_cat_rbm_valid(doi_def, |
1633 | &tag[4], | |
1634 | tag_len - 4) < 0) { | |
1635 | err_offset = opt_iter + 4; | |
1636 | goto validate_return_locked; | |
1637 | } | |
1638 | } | |
1639 | break; | |
654bbc2a | 1640 | case CIPSO_V4_TAG_ENUM: |
15c45f7b | 1641 | if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) { |
654bbc2a PM |
1642 | err_offset = opt_iter + 1; |
1643 | goto validate_return_locked; | |
1644 | } | |
1645 | ||
1646 | if (cipso_v4_map_lvl_valid(doi_def, | |
1647 | tag[3]) < 0) { | |
1648 | err_offset = opt_iter + 3; | |
1649 | goto validate_return_locked; | |
1650 | } | |
15c45f7b | 1651 | if (tag_len > CIPSO_V4_TAG_ENUM_BLEN && |
654bbc2a PM |
1652 | cipso_v4_map_cat_enum_valid(doi_def, |
1653 | &tag[4], | |
1654 | tag_len - 4) < 0) { | |
1655 | err_offset = opt_iter + 4; | |
1656 | goto validate_return_locked; | |
1657 | } | |
1658 | break; | |
484b3669 | 1659 | case CIPSO_V4_TAG_RANGE: |
15c45f7b | 1660 | if (tag_len < CIPSO_V4_TAG_RNG_BLEN) { |
484b3669 PM |
1661 | err_offset = opt_iter + 1; |
1662 | goto validate_return_locked; | |
1663 | } | |
1664 | ||
1665 | if (cipso_v4_map_lvl_valid(doi_def, | |
1666 | tag[3]) < 0) { | |
1667 | err_offset = opt_iter + 3; | |
1668 | goto validate_return_locked; | |
1669 | } | |
15c45f7b | 1670 | if (tag_len > CIPSO_V4_TAG_RNG_BLEN && |
484b3669 PM |
1671 | cipso_v4_map_cat_rng_valid(doi_def, |
1672 | &tag[4], | |
1673 | tag_len - 4) < 0) { | |
1674 | err_offset = opt_iter + 4; | |
1675 | goto validate_return_locked; | |
1676 | } | |
1677 | break; | |
15c45f7b PM |
1678 | case CIPSO_V4_TAG_LOCAL: |
1679 | /* This is a non-standard tag that we only allow for | |
1680 | * local connections, so if the incoming interface is | |
1681 | * not the loopback device drop the packet. */ | |
1682 | if (!(skb->dev->flags & IFF_LOOPBACK)) { | |
1683 | err_offset = opt_iter; | |
1684 | goto validate_return_locked; | |
1685 | } | |
1686 | if (tag_len != CIPSO_V4_TAG_LOC_BLEN) { | |
1687 | err_offset = opt_iter + 1; | |
1688 | goto validate_return_locked; | |
1689 | } | |
1690 | break; | |
446fda4f PM |
1691 | default: |
1692 | err_offset = opt_iter; | |
1693 | goto validate_return_locked; | |
1694 | } | |
1695 | ||
1696 | tag += tag_len; | |
1697 | opt_iter += tag_len; | |
1698 | } | |
1699 | ||
1700 | validate_return_locked: | |
1701 | rcu_read_unlock(); | |
1702 | validate_return: | |
1703 | *option = opt + err_offset; | |
1704 | return err_offset; | |
1705 | } | |
1706 | ||
1707 | /** | |
1708 | * cipso_v4_error - Send the correct reponse for a bad packet | |
1709 | * @skb: the packet | |
1710 | * @error: the error code | |
1711 | * @gateway: CIPSO gateway flag | |
1712 | * | |
1713 | * Description: | |
1714 | * Based on the error code given in @error, send an ICMP error message back to | |
1715 | * the originating host. From the IETF draft ... | |
1716 | * | |
1717 | * "If the contents of the CIPSO [option] are valid but the security label is | |
1718 | * outside of the configured host or port label range, the datagram is | |
1719 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and | |
1720 | * returned. The code field of the ICMP is set to 'communication with | |
1721 | * destination network administratively prohibited' (code 9) or to | |
1722 | * 'communication with destination host administratively prohibited' | |
1723 | * (code 10). The value of the code is dependent on whether the originator | |
1724 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The | |
1725 | * recipient of the ICMP message MUST be able to handle either value. The | |
1726 | * same procedure is performed if a CIPSO [option] can not be added to an | |
1727 | * IP packet because it is too large to fit in the IP options area." | |
1728 | * | |
1729 | * "If the error is triggered by receipt of an ICMP message, the message is | |
1730 | * discarded and no response is permitted (consistent with general ICMP | |
1731 | * processing rules)." | |
1732 | * | |
1733 | */ | |
1734 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) | |
1735 | { | |
eddc9ec5 | 1736 | if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) |
446fda4f PM |
1737 | return; |
1738 | ||
1739 | if (gateway) | |
1740 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0); | |
1741 | else | |
1742 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0); | |
1743 | } | |
1744 | ||
1745 | /** | |
948bf85c PM |
1746 | * cipso_v4_genopt - Generate a CIPSO option |
1747 | * @buf: the option buffer | |
1748 | * @buf_len: the size of opt_buf | |
446fda4f | 1749 | * @doi_def: the CIPSO DOI to use |
948bf85c | 1750 | * @secattr: the security attributes |
446fda4f PM |
1751 | * |
1752 | * Description: | |
948bf85c PM |
1753 | * Generate a CIPSO option using the DOI definition and security attributes |
1754 | * passed to the function. Returns the length of the option on success and | |
1755 | * negative values on failure. | |
446fda4f PM |
1756 | * |
1757 | */ | |
948bf85c PM |
1758 | static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, |
1759 | const struct cipso_v4_doi *doi_def, | |
1760 | const struct netlbl_lsm_secattr *secattr) | |
446fda4f | 1761 | { |
948bf85c | 1762 | int ret_val; |
446fda4f | 1763 | u32 iter; |
446fda4f | 1764 | |
948bf85c PM |
1765 | if (buf_len <= CIPSO_V4_HDR_LEN) |
1766 | return -ENOSPC; | |
91b1ed0a | 1767 | |
446fda4f PM |
1768 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1769 | * really a good assumption to make but since we only support the MAC | |
1770 | * tags right now it is a safe assumption. */ | |
1771 | iter = 0; | |
1772 | do { | |
91b1ed0a | 1773 | memset(buf, 0, buf_len); |
446fda4f PM |
1774 | switch (doi_def->tags[iter]) { |
1775 | case CIPSO_V4_TAG_RBITMAP: | |
1776 | ret_val = cipso_v4_gentag_rbm(doi_def, | |
91b1ed0a PM |
1777 | secattr, |
1778 | &buf[CIPSO_V4_HDR_LEN], | |
1779 | buf_len - CIPSO_V4_HDR_LEN); | |
446fda4f | 1780 | break; |
654bbc2a PM |
1781 | case CIPSO_V4_TAG_ENUM: |
1782 | ret_val = cipso_v4_gentag_enum(doi_def, | |
1783 | secattr, | |
1784 | &buf[CIPSO_V4_HDR_LEN], | |
1785 | buf_len - CIPSO_V4_HDR_LEN); | |
1786 | break; | |
484b3669 PM |
1787 | case CIPSO_V4_TAG_RANGE: |
1788 | ret_val = cipso_v4_gentag_rng(doi_def, | |
1789 | secattr, | |
1790 | &buf[CIPSO_V4_HDR_LEN], | |
1791 | buf_len - CIPSO_V4_HDR_LEN); | |
1792 | break; | |
15c45f7b PM |
1793 | case CIPSO_V4_TAG_LOCAL: |
1794 | ret_val = cipso_v4_gentag_loc(doi_def, | |
1795 | secattr, | |
1796 | &buf[CIPSO_V4_HDR_LEN], | |
1797 | buf_len - CIPSO_V4_HDR_LEN); | |
1798 | break; | |
446fda4f | 1799 | default: |
948bf85c | 1800 | return -EPERM; |
446fda4f PM |
1801 | } |
1802 | ||
1803 | iter++; | |
91b1ed0a | 1804 | } while (ret_val < 0 && |
446fda4f PM |
1805 | iter < CIPSO_V4_TAG_MAXCNT && |
1806 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); | |
91b1ed0a | 1807 | if (ret_val < 0) |
948bf85c | 1808 | return ret_val; |
91b1ed0a | 1809 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
948bf85c PM |
1810 | return CIPSO_V4_HDR_LEN + ret_val; |
1811 | } | |
1812 | ||
1813 | /** | |
1814 | * cipso_v4_sock_setattr - Add a CIPSO option to a socket | |
1815 | * @sk: the socket | |
1816 | * @doi_def: the CIPSO DOI to use | |
1817 | * @secattr: the specific security attributes of the socket | |
1818 | * | |
1819 | * Description: | |
1820 | * Set the CIPSO option on the given socket using the DOI definition and | |
1821 | * security attributes passed to the function. This function requires | |
1822 | * exclusive access to @sk, which means it either needs to be in the | |
1823 | * process of being created or locked. Returns zero on success and negative | |
1824 | * values on failure. | |
1825 | * | |
1826 | */ | |
1827 | int cipso_v4_sock_setattr(struct sock *sk, | |
1828 | const struct cipso_v4_doi *doi_def, | |
1829 | const struct netlbl_lsm_secattr *secattr) | |
1830 | { | |
1831 | int ret_val = -EPERM; | |
1832 | unsigned char *buf = NULL; | |
1833 | u32 buf_len; | |
1834 | u32 opt_len; | |
1835 | struct ip_options *opt = NULL; | |
1836 | struct inet_sock *sk_inet; | |
1837 | struct inet_connection_sock *sk_conn; | |
1838 | ||
1839 | /* In the case of sock_create_lite(), the sock->sk field is not | |
1840 | * defined yet but it is not a problem as the only users of these | |
1841 | * "lite" PF_INET sockets are functions which do an accept() call | |
1842 | * afterwards so we will label the socket as part of the accept(). */ | |
1843 | if (sk == NULL) | |
1844 | return 0; | |
1845 | ||
1846 | /* We allocate the maximum CIPSO option size here so we are probably | |
1847 | * being a little wasteful, but it makes our life _much_ easier later | |
1848 | * on and after all we are only talking about 40 bytes. */ | |
1849 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1850 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
1851 | if (buf == NULL) { | |
1852 | ret_val = -ENOMEM; | |
1853 | goto socket_setattr_failure; | |
1854 | } | |
1855 | ||
1856 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1857 | if (ret_val < 0) | |
1858 | goto socket_setattr_failure; | |
1859 | buf_len = ret_val; | |
446fda4f PM |
1860 | |
1861 | /* We can't use ip_options_get() directly because it makes a call to | |
1862 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
f8687afe PM |
1863 | * we won't always have CAP_NET_RAW even though we _always_ want to |
1864 | * set the IPOPT_CIPSO option. */ | |
446fda4f PM |
1865 | opt_len = (buf_len + 3) & ~3; |
1866 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
1867 | if (opt == NULL) { | |
1868 | ret_val = -ENOMEM; | |
1869 | goto socket_setattr_failure; | |
1870 | } | |
1871 | memcpy(opt->__data, buf, buf_len); | |
1872 | opt->optlen = opt_len; | |
f8687afe | 1873 | opt->cipso = sizeof(struct iphdr); |
446fda4f PM |
1874 | kfree(buf); |
1875 | buf = NULL; | |
446fda4f PM |
1876 | |
1877 | sk_inet = inet_sk(sk); | |
1878 | if (sk_inet->is_icsk) { | |
1879 | sk_conn = inet_csk(sk); | |
1880 | if (sk_inet->opt) | |
1881 | sk_conn->icsk_ext_hdr_len -= sk_inet->opt->optlen; | |
1882 | sk_conn->icsk_ext_hdr_len += opt->optlen; | |
1883 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
1884 | } | |
1885 | opt = xchg(&sk_inet->opt, opt); | |
1886 | kfree(opt); | |
1887 | ||
1888 | return 0; | |
1889 | ||
1890 | socket_setattr_failure: | |
1891 | kfree(buf); | |
1892 | kfree(opt); | |
1893 | return ret_val; | |
1894 | } | |
1895 | ||
014ab19a PM |
1896 | /** |
1897 | * cipso_v4_sock_delattr - Delete the CIPSO option from a socket | |
1898 | * @sk: the socket | |
1899 | * | |
1900 | * Description: | |
1901 | * Removes the CIPSO option from a socket, if present. | |
1902 | * | |
1903 | */ | |
1904 | void cipso_v4_sock_delattr(struct sock *sk) | |
1905 | { | |
1906 | u8 hdr_delta; | |
1907 | struct ip_options *opt; | |
1908 | struct inet_sock *sk_inet; | |
1909 | ||
1910 | sk_inet = inet_sk(sk); | |
1911 | opt = sk_inet->opt; | |
1912 | if (opt == NULL || opt->cipso == 0) | |
1913 | return; | |
1914 | ||
1915 | if (opt->srr || opt->rr || opt->ts || opt->router_alert) { | |
1916 | u8 cipso_len; | |
1917 | u8 cipso_off; | |
1918 | unsigned char *cipso_ptr; | |
1919 | int iter; | |
1920 | int optlen_new; | |
1921 | ||
1922 | cipso_off = opt->cipso - sizeof(struct iphdr); | |
1923 | cipso_ptr = &opt->__data[cipso_off]; | |
1924 | cipso_len = cipso_ptr[1]; | |
1925 | ||
1926 | if (opt->srr > opt->cipso) | |
1927 | opt->srr -= cipso_len; | |
1928 | if (opt->rr > opt->cipso) | |
1929 | opt->rr -= cipso_len; | |
1930 | if (opt->ts > opt->cipso) | |
1931 | opt->ts -= cipso_len; | |
1932 | if (opt->router_alert > opt->cipso) | |
1933 | opt->router_alert -= cipso_len; | |
1934 | opt->cipso = 0; | |
1935 | ||
1936 | memmove(cipso_ptr, cipso_ptr + cipso_len, | |
1937 | opt->optlen - cipso_off - cipso_len); | |
1938 | ||
1939 | /* determining the new total option length is tricky because of | |
1940 | * the padding necessary, the only thing i can think to do at | |
1941 | * this point is walk the options one-by-one, skipping the | |
1942 | * padding at the end to determine the actual option size and | |
1943 | * from there we can determine the new total option length */ | |
1944 | iter = 0; | |
1945 | optlen_new = 0; | |
1946 | while (iter < opt->optlen) | |
1947 | if (opt->__data[iter] != IPOPT_NOP) { | |
1948 | iter += opt->__data[iter + 1]; | |
1949 | optlen_new = iter; | |
1950 | } else | |
1951 | iter++; | |
1952 | hdr_delta = opt->optlen; | |
1953 | opt->optlen = (optlen_new + 3) & ~3; | |
1954 | hdr_delta -= opt->optlen; | |
1955 | } else { | |
1956 | /* only the cipso option was present on the socket so we can | |
1957 | * remove the entire option struct */ | |
1958 | sk_inet->opt = NULL; | |
1959 | hdr_delta = opt->optlen; | |
1960 | kfree(opt); | |
1961 | } | |
1962 | ||
1963 | if (sk_inet->is_icsk && hdr_delta > 0) { | |
1964 | struct inet_connection_sock *sk_conn = inet_csk(sk); | |
1965 | sk_conn->icsk_ext_hdr_len -= hdr_delta; | |
1966 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
1967 | } | |
1968 | } | |
1969 | ||
446fda4f | 1970 | /** |
63d804ea PM |
1971 | * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions |
1972 | * @cipso: the CIPSO v4 option | |
446fda4f PM |
1973 | * @secattr: the security attributes |
1974 | * | |
1975 | * Description: | |
63d804ea PM |
1976 | * Inspect @cipso and return the security attributes in @secattr. Returns zero |
1977 | * on success and negative values on failure. | |
446fda4f PM |
1978 | * |
1979 | */ | |
63d804ea PM |
1980 | static int cipso_v4_getattr(const unsigned char *cipso, |
1981 | struct netlbl_lsm_secattr *secattr) | |
446fda4f PM |
1982 | { |
1983 | int ret_val = -ENOMSG; | |
446fda4f PM |
1984 | u32 doi; |
1985 | struct cipso_v4_doi *doi_def; | |
1986 | ||
63d804ea PM |
1987 | if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0) |
1988 | return 0; | |
446fda4f | 1989 | |
d3e2ce3b | 1990 | doi = get_unaligned_be32(&cipso[2]); |
446fda4f | 1991 | rcu_read_lock(); |
9bb5fd2b | 1992 | doi_def = cipso_v4_doi_search(doi); |
63d804ea PM |
1993 | if (doi_def == NULL) |
1994 | goto getattr_return; | |
91b1ed0a PM |
1995 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1996 | * really a good assumption to make but since we only support the MAC | |
1997 | * tags right now it is a safe assumption. */ | |
63d804ea | 1998 | switch (cipso[6]) { |
446fda4f | 1999 | case CIPSO_V4_TAG_RBITMAP: |
63d804ea | 2000 | ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr); |
446fda4f | 2001 | break; |
654bbc2a | 2002 | case CIPSO_V4_TAG_ENUM: |
63d804ea | 2003 | ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr); |
654bbc2a | 2004 | break; |
484b3669 | 2005 | case CIPSO_V4_TAG_RANGE: |
63d804ea | 2006 | ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr); |
484b3669 | 2007 | break; |
15c45f7b PM |
2008 | case CIPSO_V4_TAG_LOCAL: |
2009 | ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr); | |
2010 | break; | |
446fda4f | 2011 | } |
16efd454 PM |
2012 | if (ret_val == 0) |
2013 | secattr->type = NETLBL_NLTYPE_CIPSOV4; | |
446fda4f | 2014 | |
63d804ea PM |
2015 | getattr_return: |
2016 | rcu_read_unlock(); | |
14a72f53 PM |
2017 | return ret_val; |
2018 | } | |
2019 | ||
63d804ea PM |
2020 | /** |
2021 | * cipso_v4_sock_getattr - Get the security attributes from a sock | |
2022 | * @sk: the sock | |
2023 | * @secattr: the security attributes | |
2024 | * | |
2025 | * Description: | |
2026 | * Query @sk to see if there is a CIPSO option attached to the sock and if | |
2027 | * there is return the CIPSO security attributes in @secattr. This function | |
2028 | * requires that @sk be locked, or privately held, but it does not do any | |
2029 | * locking itself. Returns zero on success and negative values on failure. | |
2030 | * | |
2031 | */ | |
2032 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) | |
2033 | { | |
2034 | struct ip_options *opt; | |
2035 | ||
2036 | opt = inet_sk(sk)->opt; | |
2037 | if (opt == NULL || opt->cipso == 0) | |
2038 | return -ENOMSG; | |
2039 | ||
2040 | return cipso_v4_getattr(opt->__data + opt->cipso - sizeof(struct iphdr), | |
2041 | secattr); | |
2042 | } | |
2043 | ||
948bf85c PM |
2044 | /** |
2045 | * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet | |
2046 | * @skb: the packet | |
2047 | * @secattr: the security attributes | |
2048 | * | |
2049 | * Description: | |
2050 | * Set the CIPSO option on the given packet based on the security attributes. | |
2051 | * Returns a pointer to the IP header on success and NULL on failure. | |
2052 | * | |
2053 | */ | |
2054 | int cipso_v4_skbuff_setattr(struct sk_buff *skb, | |
2055 | const struct cipso_v4_doi *doi_def, | |
2056 | const struct netlbl_lsm_secattr *secattr) | |
2057 | { | |
2058 | int ret_val; | |
2059 | struct iphdr *iph; | |
2060 | struct ip_options *opt = &IPCB(skb)->opt; | |
2061 | unsigned char buf[CIPSO_V4_OPT_LEN_MAX]; | |
2062 | u32 buf_len = CIPSO_V4_OPT_LEN_MAX; | |
2063 | u32 opt_len; | |
2064 | int len_delta; | |
2065 | ||
00af5c69 | 2066 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); |
2067 | if (ret_val < 0) | |
2068 | return ret_val; | |
2069 | buf_len = ret_val; | |
948bf85c PM |
2070 | opt_len = (buf_len + 3) & ~3; |
2071 | ||
2072 | /* we overwrite any existing options to ensure that we have enough | |
2073 | * room for the CIPSO option, the reason is that we _need_ to guarantee | |
2074 | * that the security label is applied to the packet - we do the same | |
2075 | * thing when using the socket options and it hasn't caused a problem, | |
2076 | * if we need to we can always revisit this choice later */ | |
2077 | ||
2078 | len_delta = opt_len - opt->optlen; | |
2079 | /* if we don't ensure enough headroom we could panic on the skb_push() | |
2080 | * call below so make sure we have enough, we are also "mangling" the | |
2081 | * packet so we should probably do a copy-on-write call anyway */ | |
2082 | ret_val = skb_cow(skb, skb_headroom(skb) + len_delta); | |
2083 | if (ret_val < 0) | |
2084 | return ret_val; | |
2085 | ||
2086 | if (len_delta > 0) { | |
2087 | /* we assume that the header + opt->optlen have already been | |
2088 | * "pushed" in ip_options_build() or similar */ | |
2089 | iph = ip_hdr(skb); | |
2090 | skb_push(skb, len_delta); | |
2091 | memmove((char *)iph - len_delta, iph, iph->ihl << 2); | |
2092 | skb_reset_network_header(skb); | |
2093 | iph = ip_hdr(skb); | |
2094 | } else if (len_delta < 0) { | |
2095 | iph = ip_hdr(skb); | |
2096 | memset(iph + 1, IPOPT_NOP, opt->optlen); | |
2097 | } else | |
2098 | iph = ip_hdr(skb); | |
2099 | ||
2100 | if (opt->optlen > 0) | |
2101 | memset(opt, 0, sizeof(*opt)); | |
2102 | opt->optlen = opt_len; | |
2103 | opt->cipso = sizeof(struct iphdr); | |
2104 | opt->is_changed = 1; | |
2105 | ||
2106 | /* we have to do the following because we are being called from a | |
2107 | * netfilter hook which means the packet already has had the header | |
2108 | * fields populated and the checksum calculated - yes this means we | |
2109 | * are doing more work than needed but we do it to keep the core | |
2110 | * stack clean and tidy */ | |
2111 | memcpy(iph + 1, buf, buf_len); | |
2112 | if (opt_len > buf_len) | |
2113 | memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); | |
2114 | if (len_delta != 0) { | |
2115 | iph->ihl = 5 + (opt_len >> 2); | |
2116 | iph->tot_len = htons(skb->len); | |
2117 | } | |
2118 | ip_send_check(iph); | |
2119 | ||
2120 | return 0; | |
2121 | } | |
2122 | ||
2123 | /** | |
2124 | * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet | |
2125 | * @skb: the packet | |
2126 | * | |
2127 | * Description: | |
2128 | * Removes any and all CIPSO options from the given packet. Returns zero on | |
2129 | * success, negative values on failure. | |
2130 | * | |
2131 | */ | |
2132 | int cipso_v4_skbuff_delattr(struct sk_buff *skb) | |
2133 | { | |
2134 | int ret_val; | |
2135 | struct iphdr *iph; | |
2136 | struct ip_options *opt = &IPCB(skb)->opt; | |
2137 | unsigned char *cipso_ptr; | |
2138 | ||
2139 | if (opt->cipso == 0) | |
2140 | return 0; | |
2141 | ||
2142 | /* since we are changing the packet we should make a copy */ | |
2143 | ret_val = skb_cow(skb, skb_headroom(skb)); | |
2144 | if (ret_val < 0) | |
2145 | return ret_val; | |
2146 | ||
2147 | /* the easiest thing to do is just replace the cipso option with noop | |
2148 | * options since we don't change the size of the packet, although we | |
2149 | * still need to recalculate the checksum */ | |
2150 | ||
2151 | iph = ip_hdr(skb); | |
2152 | cipso_ptr = (unsigned char *)iph + opt->cipso; | |
2153 | memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); | |
2154 | opt->cipso = 0; | |
2155 | opt->is_changed = 1; | |
2156 | ||
2157 | ip_send_check(iph); | |
2158 | ||
2159 | return 0; | |
2160 | } | |
2161 | ||
446fda4f PM |
2162 | /** |
2163 | * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option | |
2164 | * @skb: the packet | |
2165 | * @secattr: the security attributes | |
2166 | * | |
2167 | * Description: | |
2168 | * Parse the given packet's CIPSO option and return the security attributes. | |
2169 | * Returns zero on success and negative values on failure. | |
2170 | * | |
2171 | */ | |
2172 | int cipso_v4_skbuff_getattr(const struct sk_buff *skb, | |
2173 | struct netlbl_lsm_secattr *secattr) | |
2174 | { | |
63d804ea | 2175 | return cipso_v4_getattr(CIPSO_V4_OPTPTR(skb), secattr); |
446fda4f PM |
2176 | } |
2177 | ||
2178 | /* | |
2179 | * Setup Functions | |
2180 | */ | |
2181 | ||
2182 | /** | |
2183 | * cipso_v4_init - Initialize the CIPSO module | |
2184 | * | |
2185 | * Description: | |
2186 | * Initialize the CIPSO module and prepare it for use. Returns zero on success | |
2187 | * and negative values on failure. | |
2188 | * | |
2189 | */ | |
2190 | static int __init cipso_v4_init(void) | |
2191 | { | |
2192 | int ret_val; | |
2193 | ||
2194 | ret_val = cipso_v4_cache_init(); | |
2195 | if (ret_val != 0) | |
2196 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", | |
2197 | ret_val); | |
2198 | ||
2199 | return 0; | |
2200 | } | |
2201 | ||
2202 | subsys_initcall(cipso_v4_init); |