Commit | Line | Data |
---|---|---|
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 | |
586c2500 | 6 | * FIPS-188. While CIPSO never became a full IETF RFC standard many vendors |
446fda4f PM |
7 | * have chosen to adopt the protocol and over the years it has become a |
8 | * de-facto standard for labeled networking. | |
9 | * | |
586c2500 PM |
10 | * The CIPSO draft specification can be found in the kernel's Documentation |
11 | * directory as well as the following URL: | |
631dd1a8 | 12 | * http://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt |
586c2500 PM |
13 | * The FIPS-188 specification can be found at the following URL: |
14 | * http://www.itl.nist.gov/fipspubs/fip188.htm | |
15 | * | |
446fda4f PM |
16 | * Author: Paul Moore <paul.moore@hp.com> |
17 | * | |
18 | */ | |
19 | ||
20 | /* | |
948bf85c | 21 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 |
446fda4f PM |
22 | * |
23 | * This program is free software; you can redistribute it and/or modify | |
24 | * it under the terms of the GNU General Public License as published by | |
25 | * the Free Software Foundation; either version 2 of the License, or | |
26 | * (at your option) any later version. | |
27 | * | |
28 | * This program is distributed in the hope that it will be useful, | |
29 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
30 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
31 | * the GNU General Public License for more details. | |
32 | * | |
33 | * You should have received a copy of the GNU General Public License | |
a99421d9 | 34 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
446fda4f PM |
35 | * |
36 | */ | |
37 | ||
38 | #include <linux/init.h> | |
39 | #include <linux/types.h> | |
40 | #include <linux/rcupdate.h> | |
41 | #include <linux/list.h> | |
42 | #include <linux/spinlock.h> | |
43 | #include <linux/string.h> | |
44 | #include <linux/jhash.h> | |
6c2e8ac0 | 45 | #include <linux/audit.h> |
5a0e3ad6 | 46 | #include <linux/slab.h> |
446fda4f PM |
47 | #include <net/ip.h> |
48 | #include <net/icmp.h> | |
49 | #include <net/tcp.h> | |
50 | #include <net/netlabel.h> | |
51 | #include <net/cipso_ipv4.h> | |
60063497 | 52 | #include <linux/atomic.h> |
4c787b16 | 53 | #include <linux/bug.h> |
50e5d35c | 54 | #include <asm/unaligned.h> |
446fda4f | 55 | |
446fda4f | 56 | /* List of available DOI definitions */ |
446fda4f PM |
57 | /* XXX - This currently assumes a minimal number of different DOIs in use, |
58 | * if in practice there are a lot of different DOIs this list should | |
59 | * probably be turned into a hash table or something similar so we | |
60 | * can do quick lookups. */ | |
8ce11e6a | 61 | static DEFINE_SPINLOCK(cipso_v4_doi_list_lock); |
1596c97a | 62 | static LIST_HEAD(cipso_v4_doi_list); |
446fda4f PM |
63 | |
64 | /* Label mapping cache */ | |
65 | int cipso_v4_cache_enabled = 1; | |
66 | int cipso_v4_cache_bucketsize = 10; | |
67 | #define CIPSO_V4_CACHE_BUCKETBITS 7 | |
68 | #define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS) | |
69 | #define CIPSO_V4_CACHE_REORDERLIMIT 10 | |
70 | struct cipso_v4_map_cache_bkt { | |
71 | spinlock_t lock; | |
72 | u32 size; | |
73 | struct list_head list; | |
74 | }; | |
988b1343 | 75 | |
446fda4f PM |
76 | struct cipso_v4_map_cache_entry { |
77 | u32 hash; | |
78 | unsigned char *key; | |
79 | size_t key_len; | |
80 | ||
ffb733c6 | 81 | struct netlbl_lsm_cache *lsm_data; |
446fda4f PM |
82 | |
83 | u32 activity; | |
84 | struct list_head list; | |
85 | }; | |
988b1343 FF |
86 | |
87 | static struct cipso_v4_map_cache_bkt *cipso_v4_cache; | |
446fda4f PM |
88 | |
89 | /* Restricted bitmap (tag #1) flags */ | |
90 | int cipso_v4_rbm_optfmt = 0; | |
91 | int cipso_v4_rbm_strictvalid = 1; | |
92 | ||
f998e8cb PM |
93 | /* |
94 | * Protocol Constants | |
95 | */ | |
96 | ||
97 | /* Maximum size of the CIPSO IP option, derived from the fact that the maximum | |
98 | * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */ | |
99 | #define CIPSO_V4_OPT_LEN_MAX 40 | |
100 | ||
101 | /* Length of the base CIPSO option, this includes the option type (1 byte), the | |
102 | * option length (1 byte), and the DOI (4 bytes). */ | |
103 | #define CIPSO_V4_HDR_LEN 6 | |
104 | ||
105 | /* Base length of the restrictive category bitmap tag (tag #1). */ | |
106 | #define CIPSO_V4_TAG_RBM_BLEN 4 | |
107 | ||
108 | /* Base length of the enumerated category tag (tag #2). */ | |
109 | #define CIPSO_V4_TAG_ENUM_BLEN 4 | |
110 | ||
111 | /* Base length of the ranged categories bitmap tag (tag #5). */ | |
112 | #define CIPSO_V4_TAG_RNG_BLEN 4 | |
113 | /* The maximum number of category ranges permitted in the ranged category tag | |
114 | * (tag #5). You may note that the IETF draft states that the maximum number | |
115 | * of category ranges is 7, but if the low end of the last category range is | |
25985edc | 116 | * zero then it is possible to fit 8 category ranges because the zero should |
f998e8cb PM |
117 | * be omitted. */ |
118 | #define CIPSO_V4_TAG_RNG_CAT_MAX 8 | |
119 | ||
15c45f7b PM |
120 | /* Base length of the local tag (non-standard tag). |
121 | * Tag definition (may change between kernel versions) | |
122 | * | |
123 | * 0 8 16 24 32 | |
124 | * +----------+----------+----------+----------+ | |
125 | * | 10000000 | 00000110 | 32-bit secid value | | |
126 | * +----------+----------+----------+----------+ | |
127 | * | in (host byte order)| | |
128 | * +----------+----------+ | |
129 | * | |
130 | */ | |
131 | #define CIPSO_V4_TAG_LOC_BLEN 6 | |
132 | ||
446fda4f PM |
133 | /* |
134 | * Helper Functions | |
135 | */ | |
136 | ||
137 | /** | |
138 | * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit | |
139 | * @bitmap: the bitmap | |
140 | * @bitmap_len: length in bits | |
141 | * @offset: starting offset | |
142 | * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit | |
143 | * | |
144 | * Description: | |
145 | * Starting at @offset, walk the bitmap from left to right until either the | |
146 | * desired bit is found or we reach the end. Return the bit offset, -1 if | |
147 | * not found, or -2 if error. | |
148 | */ | |
149 | static int cipso_v4_bitmap_walk(const unsigned char *bitmap, | |
150 | u32 bitmap_len, | |
151 | u32 offset, | |
152 | u8 state) | |
153 | { | |
154 | u32 bit_spot; | |
155 | u32 byte_offset; | |
156 | unsigned char bitmask; | |
157 | unsigned char byte; | |
158 | ||
159 | /* gcc always rounds to zero when doing integer division */ | |
160 | byte_offset = offset / 8; | |
161 | byte = bitmap[byte_offset]; | |
162 | bit_spot = offset; | |
163 | bitmask = 0x80 >> (offset % 8); | |
164 | ||
165 | while (bit_spot < bitmap_len) { | |
166 | if ((state && (byte & bitmask) == bitmask) || | |
167 | (state == 0 && (byte & bitmask) == 0)) | |
168 | return bit_spot; | |
169 | ||
170 | bit_spot++; | |
171 | bitmask >>= 1; | |
172 | if (bitmask == 0) { | |
173 | byte = bitmap[++byte_offset]; | |
174 | bitmask = 0x80; | |
175 | } | |
176 | } | |
177 | ||
178 | return -1; | |
179 | } | |
180 | ||
181 | /** | |
182 | * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap | |
183 | * @bitmap: the bitmap | |
184 | * @bit: the bit | |
185 | * @state: if non-zero, set the bit (1) else clear the bit (0) | |
186 | * | |
187 | * Description: | |
188 | * Set a single bit in the bitmask. Returns zero on success, negative values | |
189 | * on error. | |
190 | */ | |
191 | static void cipso_v4_bitmap_setbit(unsigned char *bitmap, | |
192 | u32 bit, | |
193 | u8 state) | |
194 | { | |
195 | u32 byte_spot; | |
196 | u8 bitmask; | |
197 | ||
198 | /* gcc always rounds to zero when doing integer division */ | |
199 | byte_spot = bit / 8; | |
200 | bitmask = 0x80 >> (bit % 8); | |
201 | if (state) | |
202 | bitmap[byte_spot] |= bitmask; | |
203 | else | |
204 | bitmap[byte_spot] &= ~bitmask; | |
205 | } | |
206 | ||
446fda4f PM |
207 | /** |
208 | * cipso_v4_cache_entry_free - Frees a cache entry | |
209 | * @entry: the entry to free | |
210 | * | |
211 | * Description: | |
ffb733c6 | 212 | * This function frees the memory associated with a cache entry including the |
213 | * LSM cache data if there are no longer any users, i.e. reference count == 0. | |
446fda4f PM |
214 | * |
215 | */ | |
216 | static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) | |
217 | { | |
ffb733c6 | 218 | if (entry->lsm_data) |
219 | netlbl_secattr_cache_free(entry->lsm_data); | |
446fda4f PM |
220 | kfree(entry->key); |
221 | kfree(entry); | |
222 | } | |
223 | ||
224 | /** | |
225 | * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache | |
226 | * @key: the hash key | |
227 | * @key_len: the length of the key in bytes | |
228 | * | |
229 | * Description: | |
230 | * The CIPSO tag hashing function. Returns a 32-bit hash value. | |
231 | * | |
232 | */ | |
233 | static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) | |
234 | { | |
235 | return jhash(key, key_len, 0); | |
236 | } | |
237 | ||
238 | /* | |
239 | * Label Mapping Cache Functions | |
240 | */ | |
241 | ||
242 | /** | |
243 | * cipso_v4_cache_init - Initialize the CIPSO cache | |
244 | * | |
245 | * Description: | |
246 | * Initializes the CIPSO label mapping cache, this function should be called | |
247 | * before any of the other functions defined in this file. Returns zero on | |
248 | * success, negative values on error. | |
249 | * | |
250 | */ | |
cb57659a | 251 | static int __init cipso_v4_cache_init(void) |
446fda4f PM |
252 | { |
253 | u32 iter; | |
254 | ||
255 | cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS, | |
256 | sizeof(struct cipso_v4_map_cache_bkt), | |
257 | GFP_KERNEL); | |
258 | if (cipso_v4_cache == NULL) | |
259 | return -ENOMEM; | |
260 | ||
261 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
262 | spin_lock_init(&cipso_v4_cache[iter].lock); | |
263 | cipso_v4_cache[iter].size = 0; | |
264 | INIT_LIST_HEAD(&cipso_v4_cache[iter].list); | |
265 | } | |
266 | ||
267 | return 0; | |
268 | } | |
269 | ||
270 | /** | |
271 | * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache | |
272 | * | |
273 | * Description: | |
274 | * Invalidates and frees any entries in the CIPSO cache. Returns zero on | |
275 | * success and negative values on failure. | |
276 | * | |
277 | */ | |
278 | void cipso_v4_cache_invalidate(void) | |
279 | { | |
280 | struct cipso_v4_map_cache_entry *entry, *tmp_entry; | |
281 | u32 iter; | |
282 | ||
283 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
609c92fe | 284 | spin_lock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
285 | list_for_each_entry_safe(entry, |
286 | tmp_entry, | |
287 | &cipso_v4_cache[iter].list, list) { | |
288 | list_del(&entry->list); | |
289 | cipso_v4_cache_entry_free(entry); | |
290 | } | |
291 | cipso_v4_cache[iter].size = 0; | |
609c92fe | 292 | spin_unlock_bh(&cipso_v4_cache[iter].lock); |
446fda4f | 293 | } |
446fda4f PM |
294 | } |
295 | ||
296 | /** | |
297 | * cipso_v4_cache_check - Check the CIPSO cache for a label mapping | |
298 | * @key: the buffer to check | |
299 | * @key_len: buffer length in bytes | |
300 | * @secattr: the security attribute struct to use | |
301 | * | |
302 | * Description: | |
303 | * This function checks the cache to see if a label mapping already exists for | |
304 | * the given key. If there is a match then the cache is adjusted and the | |
305 | * @secattr struct is populated with the correct LSM security attributes. The | |
306 | * cache is adjusted in the following manner if the entry is not already the | |
307 | * first in the cache bucket: | |
308 | * | |
309 | * 1. The cache entry's activity counter is incremented | |
310 | * 2. The previous (higher ranking) entry's activity counter is decremented | |
311 | * 3. If the difference between the two activity counters is geater than | |
312 | * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped | |
313 | * | |
314 | * Returns zero on success, -ENOENT for a cache miss, and other negative values | |
315 | * on error. | |
316 | * | |
317 | */ | |
318 | static int cipso_v4_cache_check(const unsigned char *key, | |
319 | u32 key_len, | |
320 | struct netlbl_lsm_secattr *secattr) | |
321 | { | |
322 | u32 bkt; | |
323 | struct cipso_v4_map_cache_entry *entry; | |
324 | struct cipso_v4_map_cache_entry *prev_entry = NULL; | |
325 | u32 hash; | |
326 | ||
327 | if (!cipso_v4_cache_enabled) | |
328 | return -ENOENT; | |
329 | ||
330 | hash = cipso_v4_map_cache_hash(key, key_len); | |
5e0f8923 | 331 | bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 332 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
333 | list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) { |
334 | if (entry->hash == hash && | |
335 | entry->key_len == key_len && | |
336 | memcmp(entry->key, key, key_len) == 0) { | |
337 | entry->activity += 1; | |
ffb733c6 | 338 | atomic_inc(&entry->lsm_data->refcount); |
339 | secattr->cache = entry->lsm_data; | |
701a90ba | 340 | secattr->flags |= NETLBL_SECATTR_CACHE; |
16efd454 | 341 | secattr->type = NETLBL_NLTYPE_CIPSOV4; |
446fda4f | 342 | if (prev_entry == NULL) { |
609c92fe | 343 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
344 | return 0; |
345 | } | |
346 | ||
347 | if (prev_entry->activity > 0) | |
348 | prev_entry->activity -= 1; | |
349 | if (entry->activity > prev_entry->activity && | |
350 | entry->activity - prev_entry->activity > | |
351 | CIPSO_V4_CACHE_REORDERLIMIT) { | |
352 | __list_del(entry->list.prev, entry->list.next); | |
353 | __list_add(&entry->list, | |
354 | prev_entry->list.prev, | |
355 | &prev_entry->list); | |
356 | } | |
357 | ||
609c92fe | 358 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
359 | return 0; |
360 | } | |
361 | prev_entry = entry; | |
362 | } | |
609c92fe | 363 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
364 | |
365 | return -ENOENT; | |
366 | } | |
367 | ||
368 | /** | |
369 | * cipso_v4_cache_add - Add an entry to the CIPSO cache | |
370 | * @skb: the packet | |
371 | * @secattr: the packet's security attributes | |
372 | * | |
373 | * Description: | |
374 | * Add a new entry into the CIPSO label mapping cache. Add the new entry to | |
375 | * head of the cache bucket's list, if the cache bucket is out of room remove | |
376 | * the last entry in the list first. It is important to note that there is | |
377 | * currently no checking for duplicate keys. Returns zero on success, | |
378 | * negative values on failure. | |
379 | * | |
380 | */ | |
381 | int cipso_v4_cache_add(const struct sk_buff *skb, | |
382 | const struct netlbl_lsm_secattr *secattr) | |
383 | { | |
384 | int ret_val = -EPERM; | |
385 | u32 bkt; | |
386 | struct cipso_v4_map_cache_entry *entry = NULL; | |
387 | struct cipso_v4_map_cache_entry *old_entry = NULL; | |
388 | unsigned char *cipso_ptr; | |
389 | u32 cipso_ptr_len; | |
390 | ||
391 | if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) | |
392 | return 0; | |
393 | ||
394 | cipso_ptr = CIPSO_V4_OPTPTR(skb); | |
395 | cipso_ptr_len = cipso_ptr[1]; | |
396 | ||
397 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); | |
398 | if (entry == NULL) | |
399 | return -ENOMEM; | |
fac5d731 | 400 | entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC); |
446fda4f PM |
401 | if (entry->key == NULL) { |
402 | ret_val = -ENOMEM; | |
403 | goto cache_add_failure; | |
404 | } | |
446fda4f PM |
405 | entry->key_len = cipso_ptr_len; |
406 | entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len); | |
ffb733c6 | 407 | atomic_inc(&secattr->cache->refcount); |
408 | entry->lsm_data = secattr->cache; | |
446fda4f | 409 | |
5e0f8923 | 410 | bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 411 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
412 | if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { |
413 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
414 | cipso_v4_cache[bkt].size += 1; | |
415 | } else { | |
416 | old_entry = list_entry(cipso_v4_cache[bkt].list.prev, | |
417 | struct cipso_v4_map_cache_entry, list); | |
418 | list_del(&old_entry->list); | |
419 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
420 | cipso_v4_cache_entry_free(old_entry); | |
421 | } | |
609c92fe | 422 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
423 | |
424 | return 0; | |
425 | ||
426 | cache_add_failure: | |
427 | if (entry) | |
428 | cipso_v4_cache_entry_free(entry); | |
429 | return ret_val; | |
430 | } | |
431 | ||
432 | /* | |
433 | * DOI List Functions | |
434 | */ | |
435 | ||
436 | /** | |
437 | * cipso_v4_doi_search - Searches for a DOI definition | |
438 | * @doi: the DOI to search for | |
439 | * | |
440 | * Description: | |
441 | * Search the DOI definition list for a DOI definition with a DOI value that | |
25985edc | 442 | * matches @doi. The caller is responsible for calling rcu_read_[un]lock(). |
446fda4f PM |
443 | * Returns a pointer to the DOI definition on success and NULL on failure. |
444 | */ | |
445 | static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) | |
446 | { | |
447 | struct cipso_v4_doi *iter; | |
448 | ||
449 | list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) | |
b1edeb10 | 450 | if (iter->doi == doi && atomic_read(&iter->refcount)) |
446fda4f PM |
451 | return iter; |
452 | return NULL; | |
453 | } | |
454 | ||
455 | /** | |
456 | * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine | |
457 | * @doi_def: the DOI structure | |
6c2e8ac0 | 458 | * @audit_info: NetLabel audit information |
446fda4f PM |
459 | * |
460 | * Description: | |
461 | * The caller defines a new DOI for use by the CIPSO engine and calls this | |
462 | * function to add it to the list of acceptable domains. The caller must | |
463 | * ensure that the mapping table specified in @doi_def->map meets all of the | |
464 | * requirements of the mapping type (see cipso_ipv4.h for details). Returns | |
465 | * zero on success and non-zero on failure. | |
466 | * | |
467 | */ | |
6c2e8ac0 PM |
468 | int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, |
469 | struct netlbl_audit *audit_info) | |
446fda4f | 470 | { |
6c2e8ac0 | 471 | int ret_val = -EINVAL; |
6ce61a7c | 472 | u32 iter; |
6c2e8ac0 PM |
473 | u32 doi; |
474 | u32 doi_type; | |
475 | struct audit_buffer *audit_buf; | |
476 | ||
477 | doi = doi_def->doi; | |
478 | doi_type = doi_def->type; | |
6ce61a7c | 479 | |
56755924 | 480 | if (doi_def->doi == CIPSO_V4_DOI_UNKNOWN) |
6c2e8ac0 | 481 | goto doi_add_return; |
6ce61a7c PM |
482 | for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) { |
483 | switch (doi_def->tags[iter]) { | |
484 | case CIPSO_V4_TAG_RBITMAP: | |
485 | break; | |
484b3669 | 486 | case CIPSO_V4_TAG_RANGE: |
654bbc2a PM |
487 | case CIPSO_V4_TAG_ENUM: |
488 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
6c2e8ac0 | 489 | goto doi_add_return; |
654bbc2a | 490 | break; |
15c45f7b PM |
491 | case CIPSO_V4_TAG_LOCAL: |
492 | if (doi_def->type != CIPSO_V4_MAP_LOCAL) | |
6c2e8ac0 PM |
493 | goto doi_add_return; |
494 | break; | |
495 | case CIPSO_V4_TAG_INVALID: | |
496 | if (iter == 0) | |
497 | goto doi_add_return; | |
15c45f7b | 498 | break; |
6ce61a7c | 499 | default: |
6c2e8ac0 | 500 | goto doi_add_return; |
6ce61a7c PM |
501 | } |
502 | } | |
446fda4f | 503 | |
b1edeb10 | 504 | atomic_set(&doi_def->refcount, 1); |
446fda4f | 505 | |
446fda4f | 506 | spin_lock(&cipso_v4_doi_list_lock); |
6c2e8ac0 PM |
507 | if (cipso_v4_doi_search(doi_def->doi) != NULL) { |
508 | spin_unlock(&cipso_v4_doi_list_lock); | |
509 | ret_val = -EEXIST; | |
510 | goto doi_add_return; | |
511 | } | |
446fda4f PM |
512 | list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list); |
513 | spin_unlock(&cipso_v4_doi_list_lock); | |
6c2e8ac0 PM |
514 | ret_val = 0; |
515 | ||
516 | doi_add_return: | |
517 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info); | |
518 | if (audit_buf != NULL) { | |
519 | const char *type_str; | |
520 | switch (doi_type) { | |
521 | case CIPSO_V4_MAP_TRANS: | |
522 | type_str = "trans"; | |
523 | break; | |
524 | case CIPSO_V4_MAP_PASS: | |
525 | type_str = "pass"; | |
526 | break; | |
527 | case CIPSO_V4_MAP_LOCAL: | |
528 | type_str = "local"; | |
529 | break; | |
530 | default: | |
531 | type_str = "(unknown)"; | |
532 | } | |
533 | audit_log_format(audit_buf, | |
534 | " cipso_doi=%u cipso_type=%s res=%u", | |
535 | doi, type_str, ret_val == 0 ? 1 : 0); | |
536 | audit_log_end(audit_buf); | |
537 | } | |
446fda4f | 538 | |
6c2e8ac0 | 539 | return ret_val; |
446fda4f PM |
540 | } |
541 | ||
b1edeb10 PM |
542 | /** |
543 | * cipso_v4_doi_free - Frees a DOI definition | |
4973404f | 544 | * @doi_def: the DOI definition |
b1edeb10 PM |
545 | * |
546 | * Description: | |
547 | * This function frees all of the memory associated with a DOI definition. | |
548 | * | |
549 | */ | |
550 | void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) | |
551 | { | |
552 | if (doi_def == NULL) | |
553 | return; | |
554 | ||
555 | switch (doi_def->type) { | |
15c45f7b | 556 | case CIPSO_V4_MAP_TRANS: |
b1edeb10 PM |
557 | kfree(doi_def->map.std->lvl.cipso); |
558 | kfree(doi_def->map.std->lvl.local); | |
559 | kfree(doi_def->map.std->cat.cipso); | |
560 | kfree(doi_def->map.std->cat.local); | |
561 | break; | |
562 | } | |
563 | kfree(doi_def); | |
564 | } | |
565 | ||
566 | /** | |
567 | * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer | |
568 | * @entry: the entry's RCU field | |
569 | * | |
570 | * Description: | |
571 | * This function is designed to be used as a callback to the call_rcu() | |
572 | * function so that the memory allocated to the DOI definition can be released | |
573 | * safely. | |
574 | * | |
575 | */ | |
576 | static void cipso_v4_doi_free_rcu(struct rcu_head *entry) | |
577 | { | |
578 | struct cipso_v4_doi *doi_def; | |
579 | ||
580 | doi_def = container_of(entry, struct cipso_v4_doi, rcu); | |
581 | cipso_v4_doi_free(doi_def); | |
582 | } | |
583 | ||
446fda4f PM |
584 | /** |
585 | * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine | |
586 | * @doi: the DOI value | |
32f50cde | 587 | * @audit_secid: the LSM secid to use in the audit message |
446fda4f PM |
588 | * |
589 | * Description: | |
b1edeb10 PM |
590 | * Removes a DOI definition from the CIPSO engine. The NetLabel routines will |
591 | * be called to release their own LSM domain mappings as well as our own | |
592 | * domain list. Returns zero on success and negative values on failure. | |
446fda4f PM |
593 | * |
594 | */ | |
b1edeb10 | 595 | int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info) |
446fda4f | 596 | { |
6c2e8ac0 | 597 | int ret_val; |
446fda4f | 598 | struct cipso_v4_doi *doi_def; |
6c2e8ac0 | 599 | struct audit_buffer *audit_buf; |
446fda4f | 600 | |
4be2700f PM |
601 | spin_lock(&cipso_v4_doi_list_lock); |
602 | doi_def = cipso_v4_doi_search(doi); | |
b1edeb10 | 603 | if (doi_def == NULL) { |
446fda4f | 604 | spin_unlock(&cipso_v4_doi_list_lock); |
6c2e8ac0 PM |
605 | ret_val = -ENOENT; |
606 | goto doi_remove_return; | |
446fda4f | 607 | } |
b1edeb10 PM |
608 | if (!atomic_dec_and_test(&doi_def->refcount)) { |
609 | spin_unlock(&cipso_v4_doi_list_lock); | |
6c2e8ac0 PM |
610 | ret_val = -EBUSY; |
611 | goto doi_remove_return; | |
b1edeb10 PM |
612 | } |
613 | list_del_rcu(&doi_def->list); | |
4be2700f | 614 | spin_unlock(&cipso_v4_doi_list_lock); |
446fda4f | 615 | |
b1edeb10 PM |
616 | cipso_v4_cache_invalidate(); |
617 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
6c2e8ac0 PM |
618 | ret_val = 0; |
619 | ||
620 | doi_remove_return: | |
621 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info); | |
622 | if (audit_buf != NULL) { | |
623 | audit_log_format(audit_buf, | |
624 | " cipso_doi=%u res=%u", | |
625 | doi, ret_val == 0 ? 1 : 0); | |
626 | audit_log_end(audit_buf); | |
627 | } | |
b1edeb10 | 628 | |
6c2e8ac0 | 629 | return ret_val; |
446fda4f PM |
630 | } |
631 | ||
632 | /** | |
b1edeb10 | 633 | * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition |
446fda4f PM |
634 | * @doi: the DOI value |
635 | * | |
636 | * Description: | |
637 | * Searches for a valid DOI definition and if one is found it is returned to | |
638 | * the caller. Otherwise NULL is returned. The caller must ensure that | |
b1edeb10 PM |
639 | * rcu_read_lock() is held while accessing the returned definition and the DOI |
640 | * definition reference count is decremented when the caller is done. | |
446fda4f PM |
641 | * |
642 | */ | |
643 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) | |
644 | { | |
b1edeb10 PM |
645 | struct cipso_v4_doi *doi_def; |
646 | ||
647 | rcu_read_lock(); | |
648 | doi_def = cipso_v4_doi_search(doi); | |
649 | if (doi_def == NULL) | |
650 | goto doi_getdef_return; | |
651 | if (!atomic_inc_not_zero(&doi_def->refcount)) | |
652 | doi_def = NULL; | |
653 | ||
654 | doi_getdef_return: | |
655 | rcu_read_unlock(); | |
656 | return doi_def; | |
657 | } | |
658 | ||
659 | /** | |
660 | * cipso_v4_doi_putdef - Releases a reference for the given DOI definition | |
661 | * @doi_def: the DOI definition | |
662 | * | |
663 | * Description: | |
664 | * Releases a DOI definition reference obtained from cipso_v4_doi_getdef(). | |
665 | * | |
666 | */ | |
667 | void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) | |
668 | { | |
669 | if (doi_def == NULL) | |
670 | return; | |
671 | ||
672 | if (!atomic_dec_and_test(&doi_def->refcount)) | |
673 | return; | |
674 | spin_lock(&cipso_v4_doi_list_lock); | |
675 | list_del_rcu(&doi_def->list); | |
676 | spin_unlock(&cipso_v4_doi_list_lock); | |
677 | ||
678 | cipso_v4_cache_invalidate(); | |
679 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
446fda4f PM |
680 | } |
681 | ||
682 | /** | |
fcd48280 PM |
683 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
684 | * @skip_cnt: skip past this number of DOI definitions, updated | |
685 | * @callback: callback for each DOI definition | |
686 | * @cb_arg: argument for the callback function | |
446fda4f PM |
687 | * |
688 | * Description: | |
fcd48280 PM |
689 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
690 | * For each entry call @callback, if @callback returns a negative value stop | |
691 | * 'walking' through the list and return. Updates the value in @skip_cnt upon | |
692 | * return. Returns zero on success, negative values on failure. | |
446fda4f PM |
693 | * |
694 | */ | |
fcd48280 PM |
695 | int cipso_v4_doi_walk(u32 *skip_cnt, |
696 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), | |
697 | void *cb_arg) | |
446fda4f | 698 | { |
fcd48280 | 699 | int ret_val = -ENOENT; |
446fda4f | 700 | u32 doi_cnt = 0; |
fcd48280 | 701 | struct cipso_v4_doi *iter_doi; |
446fda4f | 702 | |
446fda4f | 703 | rcu_read_lock(); |
fcd48280 | 704 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
b1edeb10 | 705 | if (atomic_read(&iter_doi->refcount) > 0) { |
fcd48280 PM |
706 | if (doi_cnt++ < *skip_cnt) |
707 | continue; | |
708 | ret_val = callback(iter_doi, cb_arg); | |
709 | if (ret_val < 0) { | |
710 | doi_cnt--; | |
711 | goto doi_walk_return; | |
446fda4f | 712 | } |
446fda4f | 713 | } |
446fda4f | 714 | |
fcd48280 | 715 | doi_walk_return: |
446fda4f | 716 | rcu_read_unlock(); |
fcd48280 PM |
717 | *skip_cnt = doi_cnt; |
718 | return ret_val; | |
446fda4f PM |
719 | } |
720 | ||
446fda4f PM |
721 | /* |
722 | * Label Mapping Functions | |
723 | */ | |
724 | ||
725 | /** | |
726 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood | |
727 | * @doi_def: the DOI definition | |
728 | * @level: the level to check | |
729 | * | |
730 | * Description: | |
731 | * Checks the given level against the given DOI definition and returns a | |
732 | * negative value if the level does not have a valid mapping and a zero value | |
733 | * if the level is defined by the DOI. | |
734 | * | |
735 | */ | |
736 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) | |
737 | { | |
738 | switch (doi_def->type) { | |
739 | case CIPSO_V4_MAP_PASS: | |
740 | return 0; | |
15c45f7b | 741 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
742 | if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL) |
743 | return 0; | |
744 | break; | |
745 | } | |
746 | ||
747 | return -EFAULT; | |
748 | } | |
749 | ||
750 | /** | |
751 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network | |
752 | * @doi_def: the DOI definition | |
753 | * @host_lvl: the host MLS level | |
754 | * @net_lvl: the network/CIPSO MLS level | |
755 | * | |
756 | * Description: | |
757 | * Perform a label mapping to translate a local MLS level to the correct | |
758 | * CIPSO level using the given DOI definition. Returns zero on success, | |
759 | * negative values otherwise. | |
760 | * | |
761 | */ | |
762 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, | |
763 | u32 host_lvl, | |
764 | u32 *net_lvl) | |
765 | { | |
766 | switch (doi_def->type) { | |
767 | case CIPSO_V4_MAP_PASS: | |
768 | *net_lvl = host_lvl; | |
769 | return 0; | |
15c45f7b | 770 | case CIPSO_V4_MAP_TRANS: |
c6387a86 PM |
771 | if (host_lvl < doi_def->map.std->lvl.local_size && |
772 | doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) { | |
446fda4f PM |
773 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
774 | return 0; | |
775 | } | |
c6387a86 | 776 | return -EPERM; |
446fda4f PM |
777 | } |
778 | ||
779 | return -EINVAL; | |
780 | } | |
781 | ||
782 | /** | |
783 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host | |
784 | * @doi_def: the DOI definition | |
785 | * @net_lvl: the network/CIPSO MLS level | |
786 | * @host_lvl: the host MLS level | |
787 | * | |
788 | * Description: | |
789 | * Perform a label mapping to translate a CIPSO level to the correct local MLS | |
790 | * level using the given DOI definition. Returns zero on success, negative | |
791 | * values otherwise. | |
792 | * | |
793 | */ | |
794 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, | |
795 | u32 net_lvl, | |
796 | u32 *host_lvl) | |
797 | { | |
798 | struct cipso_v4_std_map_tbl *map_tbl; | |
799 | ||
800 | switch (doi_def->type) { | |
801 | case CIPSO_V4_MAP_PASS: | |
802 | *host_lvl = net_lvl; | |
803 | return 0; | |
15c45f7b | 804 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
805 | map_tbl = doi_def->map.std; |
806 | if (net_lvl < map_tbl->lvl.cipso_size && | |
807 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { | |
808 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; | |
809 | return 0; | |
810 | } | |
c6387a86 | 811 | return -EPERM; |
446fda4f PM |
812 | } |
813 | ||
814 | return -EINVAL; | |
815 | } | |
816 | ||
817 | /** | |
818 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid | |
819 | * @doi_def: the DOI definition | |
820 | * @bitmap: category bitmap | |
821 | * @bitmap_len: bitmap length in bytes | |
822 | * | |
823 | * Description: | |
824 | * Checks the given category bitmap against the given DOI definition and | |
825 | * returns a negative value if any of the categories in the bitmap do not have | |
826 | * a valid mapping and a zero value if all of the categories are valid. | |
827 | * | |
828 | */ | |
829 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, | |
830 | const unsigned char *bitmap, | |
831 | u32 bitmap_len) | |
832 | { | |
833 | int cat = -1; | |
834 | u32 bitmap_len_bits = bitmap_len * 8; | |
044a68ed PM |
835 | u32 cipso_cat_size; |
836 | u32 *cipso_array; | |
446fda4f PM |
837 | |
838 | switch (doi_def->type) { | |
839 | case CIPSO_V4_MAP_PASS: | |
840 | return 0; | |
15c45f7b | 841 | case CIPSO_V4_MAP_TRANS: |
044a68ed PM |
842 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
843 | cipso_array = doi_def->map.std->cat.cipso; | |
446fda4f PM |
844 | for (;;) { |
845 | cat = cipso_v4_bitmap_walk(bitmap, | |
846 | bitmap_len_bits, | |
847 | cat + 1, | |
848 | 1); | |
849 | if (cat < 0) | |
850 | break; | |
851 | if (cat >= cipso_cat_size || | |
852 | cipso_array[cat] >= CIPSO_V4_INV_CAT) | |
853 | return -EFAULT; | |
854 | } | |
855 | ||
856 | if (cat == -1) | |
857 | return 0; | |
858 | break; | |
859 | } | |
860 | ||
861 | return -EFAULT; | |
862 | } | |
863 | ||
864 | /** | |
865 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network | |
866 | * @doi_def: the DOI definition | |
02752760 | 867 | * @secattr: the security attributes |
446fda4f PM |
868 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
869 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
870 | * | |
871 | * Description: | |
872 | * Perform a label mapping to translate a local MLS category bitmap to the | |
873 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum | |
874 | * size in bytes of the network bitmap on success, negative values otherwise. | |
875 | * | |
876 | */ | |
877 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, | |
02752760 | 878 | const struct netlbl_lsm_secattr *secattr, |
446fda4f PM |
879 | unsigned char *net_cat, |
880 | u32 net_cat_len) | |
881 | { | |
882 | int host_spot = -1; | |
02752760 | 883 | u32 net_spot = CIPSO_V4_INV_CAT; |
446fda4f | 884 | u32 net_spot_max = 0; |
446fda4f | 885 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
886 | u32 host_cat_size = 0; |
887 | u32 *host_cat_array = NULL; | |
446fda4f | 888 | |
15c45f7b | 889 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
890 | host_cat_size = doi_def->map.std->cat.local_size; |
891 | host_cat_array = doi_def->map.std->cat.local; | |
02752760 PM |
892 | } |
893 | ||
894 | for (;;) { | |
4fbe63d1 PM |
895 | host_spot = netlbl_catmap_walk(secattr->attr.mls.cat, |
896 | host_spot + 1); | |
02752760 PM |
897 | if (host_spot < 0) |
898 | break; | |
899 | ||
900 | switch (doi_def->type) { | |
901 | case CIPSO_V4_MAP_PASS: | |
902 | net_spot = host_spot; | |
903 | break; | |
15c45f7b | 904 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
905 | if (host_spot >= host_cat_size) |
906 | return -EPERM; | |
446fda4f | 907 | net_spot = host_cat_array[host_spot]; |
9fade4bf PM |
908 | if (net_spot >= CIPSO_V4_INV_CAT) |
909 | return -EPERM; | |
02752760 | 910 | break; |
446fda4f | 911 | } |
02752760 PM |
912 | if (net_spot >= net_clen_bits) |
913 | return -ENOSPC; | |
914 | cipso_v4_bitmap_setbit(net_cat, net_spot, 1); | |
446fda4f | 915 | |
02752760 PM |
916 | if (net_spot > net_spot_max) |
917 | net_spot_max = net_spot; | |
446fda4f PM |
918 | } |
919 | ||
02752760 PM |
920 | if (++net_spot_max % 8) |
921 | return net_spot_max / 8 + 1; | |
922 | return net_spot_max / 8; | |
446fda4f PM |
923 | } |
924 | ||
925 | /** | |
926 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host | |
927 | * @doi_def: the DOI definition | |
928 | * @net_cat: the category bitmap in network/CIPSO format | |
929 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
02752760 | 930 | * @secattr: the security attributes |
446fda4f PM |
931 | * |
932 | * Description: | |
933 | * Perform a label mapping to translate a CIPSO bitmap to the correct local | |
02752760 PM |
934 | * MLS category bitmap using the given DOI definition. Returns zero on |
935 | * success, negative values on failure. | |
446fda4f PM |
936 | * |
937 | */ | |
938 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, | |
939 | const unsigned char *net_cat, | |
940 | u32 net_cat_len, | |
02752760 | 941 | struct netlbl_lsm_secattr *secattr) |
446fda4f | 942 | { |
02752760 | 943 | int ret_val; |
446fda4f | 944 | int net_spot = -1; |
02752760 | 945 | u32 host_spot = CIPSO_V4_INV_CAT; |
446fda4f | 946 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
947 | u32 net_cat_size = 0; |
948 | u32 *net_cat_array = NULL; | |
446fda4f | 949 | |
15c45f7b | 950 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
951 | net_cat_size = doi_def->map.std->cat.cipso_size; |
952 | net_cat_array = doi_def->map.std->cat.cipso; | |
02752760 | 953 | } |
446fda4f | 954 | |
02752760 PM |
955 | for (;;) { |
956 | net_spot = cipso_v4_bitmap_walk(net_cat, | |
957 | net_clen_bits, | |
958 | net_spot + 1, | |
959 | 1); | |
960 | if (net_spot < 0) { | |
961 | if (net_spot == -2) | |
962 | return -EFAULT; | |
963 | return 0; | |
964 | } | |
965 | ||
966 | switch (doi_def->type) { | |
967 | case CIPSO_V4_MAP_PASS: | |
968 | host_spot = net_spot; | |
969 | break; | |
15c45f7b | 970 | case CIPSO_V4_MAP_TRANS: |
02752760 PM |
971 | if (net_spot >= net_cat_size) |
972 | return -EPERM; | |
446fda4f | 973 | host_spot = net_cat_array[net_spot]; |
9fade4bf PM |
974 | if (host_spot >= CIPSO_V4_INV_CAT) |
975 | return -EPERM; | |
02752760 | 976 | break; |
446fda4f | 977 | } |
4fbe63d1 | 978 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
02752760 PM |
979 | host_spot, |
980 | GFP_ATOMIC); | |
981 | if (ret_val != 0) | |
982 | return ret_val; | |
446fda4f PM |
983 | } |
984 | ||
985 | return -EINVAL; | |
986 | } | |
987 | ||
654bbc2a PM |
988 | /** |
989 | * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid | |
990 | * @doi_def: the DOI definition | |
991 | * @enumcat: category list | |
992 | * @enumcat_len: length of the category list in bytes | |
993 | * | |
994 | * Description: | |
995 | * Checks the given categories against the given DOI definition and returns a | |
996 | * negative value if any of the categories do not have a valid mapping and a | |
997 | * zero value if all of the categories are valid. | |
998 | * | |
999 | */ | |
1000 | static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, | |
1001 | const unsigned char *enumcat, | |
1002 | u32 enumcat_len) | |
1003 | { | |
1004 | u16 cat; | |
1005 | int cat_prev = -1; | |
1006 | u32 iter; | |
1007 | ||
1008 | if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01) | |
1009 | return -EFAULT; | |
1010 | ||
1011 | for (iter = 0; iter < enumcat_len; iter += 2) { | |
d3e2ce3b | 1012 | cat = get_unaligned_be16(&enumcat[iter]); |
654bbc2a PM |
1013 | if (cat <= cat_prev) |
1014 | return -EFAULT; | |
1015 | cat_prev = cat; | |
1016 | } | |
1017 | ||
1018 | return 0; | |
1019 | } | |
1020 | ||
1021 | /** | |
1022 | * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network | |
1023 | * @doi_def: the DOI definition | |
1024 | * @secattr: the security attributes | |
1025 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1026 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1027 | * | |
1028 | * Description: | |
1029 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1030 | * correct CIPSO category list using the given DOI definition. Returns the | |
1031 | * size in bytes of the network category bitmap on success, negative values | |
1032 | * otherwise. | |
1033 | * | |
1034 | */ | |
1035 | static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, | |
1036 | const struct netlbl_lsm_secattr *secattr, | |
1037 | unsigned char *net_cat, | |
1038 | u32 net_cat_len) | |
1039 | { | |
1040 | int cat = -1; | |
1041 | u32 cat_iter = 0; | |
1042 | ||
1043 | for (;;) { | |
4fbe63d1 | 1044 | cat = netlbl_catmap_walk(secattr->attr.mls.cat, cat + 1); |
654bbc2a PM |
1045 | if (cat < 0) |
1046 | break; | |
1047 | if ((cat_iter + 2) > net_cat_len) | |
1048 | return -ENOSPC; | |
1049 | ||
1050 | *((__be16 *)&net_cat[cat_iter]) = htons(cat); | |
1051 | cat_iter += 2; | |
1052 | } | |
1053 | ||
1054 | return cat_iter; | |
1055 | } | |
1056 | ||
1057 | /** | |
1058 | * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host | |
1059 | * @doi_def: the DOI definition | |
1060 | * @net_cat: the category list in network/CIPSO format | |
1061 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1062 | * @secattr: the security attributes | |
1063 | * | |
1064 | * Description: | |
1065 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1066 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1067 | * success, negative values on failure. | |
1068 | * | |
1069 | */ | |
1070 | static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, | |
1071 | const unsigned char *net_cat, | |
1072 | u32 net_cat_len, | |
1073 | struct netlbl_lsm_secattr *secattr) | |
1074 | { | |
1075 | int ret_val; | |
1076 | u32 iter; | |
1077 | ||
1078 | for (iter = 0; iter < net_cat_len; iter += 2) { | |
4fbe63d1 PM |
1079 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
1080 | get_unaligned_be16(&net_cat[iter]), | |
1081 | GFP_ATOMIC); | |
654bbc2a PM |
1082 | if (ret_val != 0) |
1083 | return ret_val; | |
1084 | } | |
1085 | ||
1086 | return 0; | |
1087 | } | |
1088 | ||
484b3669 PM |
1089 | /** |
1090 | * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid | |
1091 | * @doi_def: the DOI definition | |
1092 | * @rngcat: category list | |
1093 | * @rngcat_len: length of the category list in bytes | |
1094 | * | |
1095 | * Description: | |
1096 | * Checks the given categories against the given DOI definition and returns a | |
1097 | * negative value if any of the categories do not have a valid mapping and a | |
1098 | * zero value if all of the categories are valid. | |
1099 | * | |
1100 | */ | |
1101 | static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, | |
1102 | const unsigned char *rngcat, | |
1103 | u32 rngcat_len) | |
1104 | { | |
1105 | u16 cat_high; | |
1106 | u16 cat_low; | |
1107 | u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1; | |
1108 | u32 iter; | |
1109 | ||
1110 | if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01) | |
1111 | return -EFAULT; | |
1112 | ||
1113 | for (iter = 0; iter < rngcat_len; iter += 4) { | |
d3e2ce3b | 1114 | cat_high = get_unaligned_be16(&rngcat[iter]); |
484b3669 | 1115 | if ((iter + 4) <= rngcat_len) |
d3e2ce3b | 1116 | cat_low = get_unaligned_be16(&rngcat[iter + 2]); |
484b3669 PM |
1117 | else |
1118 | cat_low = 0; | |
1119 | ||
1120 | if (cat_high > cat_prev) | |
1121 | return -EFAULT; | |
1122 | ||
1123 | cat_prev = cat_low; | |
1124 | } | |
1125 | ||
1126 | return 0; | |
1127 | } | |
1128 | ||
1129 | /** | |
1130 | * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network | |
1131 | * @doi_def: the DOI definition | |
1132 | * @secattr: the security attributes | |
1133 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1134 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1135 | * | |
1136 | * Description: | |
1137 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1138 | * correct CIPSO category list using the given DOI definition. Returns the | |
1139 | * size in bytes of the network category bitmap on success, negative values | |
1140 | * otherwise. | |
1141 | * | |
1142 | */ | |
1143 | static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, | |
1144 | const struct netlbl_lsm_secattr *secattr, | |
1145 | unsigned char *net_cat, | |
1146 | u32 net_cat_len) | |
1147 | { | |
484b3669 | 1148 | int iter = -1; |
f998e8cb | 1149 | u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2]; |
484b3669 PM |
1150 | u32 array_cnt = 0; |
1151 | u32 cat_size = 0; | |
1152 | ||
f998e8cb | 1153 | /* make sure we don't overflow the 'array[]' variable */ |
128c6b6c PM |
1154 | if (net_cat_len > |
1155 | (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN)) | |
1156 | return -ENOSPC; | |
484b3669 PM |
1157 | |
1158 | for (;;) { | |
4fbe63d1 | 1159 | iter = netlbl_catmap_walk(secattr->attr.mls.cat, iter + 1); |
484b3669 PM |
1160 | if (iter < 0) |
1161 | break; | |
1162 | cat_size += (iter == 0 ? 0 : sizeof(u16)); | |
1163 | if (cat_size > net_cat_len) | |
1164 | return -ENOSPC; | |
1165 | array[array_cnt++] = iter; | |
1166 | ||
4fbe63d1 | 1167 | iter = netlbl_catmap_walkrng(secattr->attr.mls.cat, iter); |
484b3669 PM |
1168 | if (iter < 0) |
1169 | return -EFAULT; | |
1170 | cat_size += sizeof(u16); | |
1171 | if (cat_size > net_cat_len) | |
1172 | return -ENOSPC; | |
1173 | array[array_cnt++] = iter; | |
1174 | } | |
1175 | ||
1176 | for (iter = 0; array_cnt > 0;) { | |
1177 | *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]); | |
1178 | iter += 2; | |
1179 | array_cnt--; | |
1180 | if (array[array_cnt] != 0) { | |
1181 | *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]); | |
1182 | iter += 2; | |
1183 | } | |
1184 | } | |
1185 | ||
1186 | return cat_size; | |
1187 | } | |
1188 | ||
1189 | /** | |
1190 | * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host | |
1191 | * @doi_def: the DOI definition | |
1192 | * @net_cat: the category list in network/CIPSO format | |
1193 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1194 | * @secattr: the security attributes | |
1195 | * | |
1196 | * Description: | |
1197 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1198 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1199 | * success, negative values on failure. | |
1200 | * | |
1201 | */ | |
1202 | static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, | |
1203 | const unsigned char *net_cat, | |
1204 | u32 net_cat_len, | |
1205 | struct netlbl_lsm_secattr *secattr) | |
1206 | { | |
1207 | int ret_val; | |
1208 | u32 net_iter; | |
1209 | u16 cat_low; | |
1210 | u16 cat_high; | |
1211 | ||
132adf54 | 1212 | for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) { |
d3e2ce3b | 1213 | cat_high = get_unaligned_be16(&net_cat[net_iter]); |
484b3669 | 1214 | if ((net_iter + 4) <= net_cat_len) |
d3e2ce3b | 1215 | cat_low = get_unaligned_be16(&net_cat[net_iter + 2]); |
484b3669 PM |
1216 | else |
1217 | cat_low = 0; | |
1218 | ||
4fbe63d1 PM |
1219 | ret_val = netlbl_catmap_setrng(&secattr->attr.mls.cat, |
1220 | cat_low, | |
1221 | cat_high, | |
1222 | GFP_ATOMIC); | |
484b3669 PM |
1223 | if (ret_val != 0) |
1224 | return ret_val; | |
1225 | } | |
1226 | ||
1227 | return 0; | |
1228 | } | |
1229 | ||
446fda4f PM |
1230 | /* |
1231 | * Protocol Handling Functions | |
1232 | */ | |
1233 | ||
446fda4f PM |
1234 | /** |
1235 | * cipso_v4_gentag_hdr - Generate a CIPSO option header | |
1236 | * @doi_def: the DOI definition | |
91b1ed0a | 1237 | * @len: the total tag length in bytes, not including this header |
446fda4f PM |
1238 | * @buf: the CIPSO option buffer |
1239 | * | |
1240 | * Description: | |
91b1ed0a | 1241 | * Write a CIPSO header into the beginning of @buffer. |
446fda4f PM |
1242 | * |
1243 | */ | |
91b1ed0a PM |
1244 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
1245 | unsigned char *buf, | |
1246 | u32 len) | |
446fda4f | 1247 | { |
446fda4f PM |
1248 | buf[0] = IPOPT_CIPSO; |
1249 | buf[1] = CIPSO_V4_HDR_LEN + len; | |
714e85be | 1250 | *(__be32 *)&buf[2] = htonl(doi_def->doi); |
446fda4f PM |
1251 | } |
1252 | ||
446fda4f PM |
1253 | /** |
1254 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) | |
1255 | * @doi_def: the DOI definition | |
1256 | * @secattr: the security attributes | |
1257 | * @buffer: the option buffer | |
1258 | * @buffer_len: length of buffer in bytes | |
1259 | * | |
1260 | * Description: | |
1261 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The | |
1262 | * actual buffer length may be larger than the indicated size due to | |
91b1ed0a PM |
1263 | * translation between host and network category bitmaps. Returns the size of |
1264 | * the tag on success, negative values on failure. | |
446fda4f PM |
1265 | * |
1266 | */ | |
1267 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, | |
1268 | const struct netlbl_lsm_secattr *secattr, | |
91b1ed0a PM |
1269 | unsigned char *buffer, |
1270 | u32 buffer_len) | |
446fda4f | 1271 | { |
701a90ba | 1272 | int ret_val; |
91b1ed0a | 1273 | u32 tag_len; |
446fda4f PM |
1274 | u32 level; |
1275 | ||
701a90ba PM |
1276 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
1277 | return -EPERM; | |
1278 | ||
16efd454 PM |
1279 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1280 | secattr->attr.mls.lvl, | |
1281 | &level); | |
91b1ed0a PM |
1282 | if (ret_val != 0) |
1283 | return ret_val; | |
446fda4f | 1284 | |
91b1ed0a | 1285 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
446fda4f | 1286 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
02752760 | 1287 | secattr, |
91b1ed0a PM |
1288 | &buffer[4], |
1289 | buffer_len - 4); | |
446fda4f | 1290 | if (ret_val < 0) |
91b1ed0a | 1291 | return ret_val; |
446fda4f PM |
1292 | |
1293 | /* This will send packets using the "optimized" format when | |
25985edc | 1294 | * possible as specified in section 3.4.2.6 of the |
446fda4f | 1295 | * CIPSO draft. */ |
701a90ba | 1296 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
91b1ed0a | 1297 | tag_len = 14; |
701a90ba | 1298 | else |
91b1ed0a PM |
1299 | tag_len = 4 + ret_val; |
1300 | } else | |
1301 | tag_len = 4; | |
446fda4f | 1302 | |
15c45f7b | 1303 | buffer[0] = CIPSO_V4_TAG_RBITMAP; |
91b1ed0a PM |
1304 | buffer[1] = tag_len; |
1305 | buffer[3] = level; | |
446fda4f | 1306 | |
91b1ed0a | 1307 | return tag_len; |
446fda4f PM |
1308 | } |
1309 | ||
1310 | /** | |
1311 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag | |
1312 | * @doi_def: the DOI definition | |
1313 | * @tag: the CIPSO tag | |
1314 | * @secattr: the security attributes | |
1315 | * | |
1316 | * Description: | |
1317 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security | |
1318 | * attributes in @secattr. Return zero on success, negatives values on | |
1319 | * failure. | |
1320 | * | |
1321 | */ | |
1322 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, | |
1323 | const unsigned char *tag, | |
1324 | struct netlbl_lsm_secattr *secattr) | |
1325 | { | |
1326 | int ret_val; | |
1327 | u8 tag_len = tag[1]; | |
1328 | u32 level; | |
1329 | ||
1330 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1331 | if (ret_val != 0) | |
1332 | return ret_val; | |
16efd454 | 1333 | secattr->attr.mls.lvl = level; |
701a90ba | 1334 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
446fda4f PM |
1335 | |
1336 | if (tag_len > 4) { | |
446fda4f PM |
1337 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, |
1338 | &tag[4], | |
1339 | tag_len - 4, | |
02752760 PM |
1340 | secattr); |
1341 | if (ret_val != 0) { | |
4fbe63d1 | 1342 | netlbl_catmap_free(secattr->attr.mls.cat); |
446fda4f PM |
1343 | return ret_val; |
1344 | } | |
02752760 PM |
1345 | |
1346 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
446fda4f PM |
1347 | } |
1348 | ||
1349 | return 0; | |
1350 | } | |
1351 | ||
654bbc2a PM |
1352 | /** |
1353 | * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) | |
1354 | * @doi_def: the DOI definition | |
1355 | * @secattr: the security attributes | |
1356 | * @buffer: the option buffer | |
1357 | * @buffer_len: length of buffer in bytes | |
1358 | * | |
1359 | * Description: | |
1360 | * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the | |
1361 | * size of the tag on success, negative values on failure. | |
1362 | * | |
1363 | */ | |
1364 | static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, | |
1365 | const struct netlbl_lsm_secattr *secattr, | |
1366 | unsigned char *buffer, | |
1367 | u32 buffer_len) | |
1368 | { | |
1369 | int ret_val; | |
1370 | u32 tag_len; | |
1371 | u32 level; | |
1372 | ||
1373 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1374 | return -EPERM; | |
1375 | ||
16efd454 PM |
1376 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1377 | secattr->attr.mls.lvl, | |
1378 | &level); | |
654bbc2a PM |
1379 | if (ret_val != 0) |
1380 | return ret_val; | |
1381 | ||
1382 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1383 | ret_val = cipso_v4_map_cat_enum_hton(doi_def, | |
1384 | secattr, | |
1385 | &buffer[4], | |
1386 | buffer_len - 4); | |
1387 | if (ret_val < 0) | |
1388 | return ret_val; | |
1389 | ||
1390 | tag_len = 4 + ret_val; | |
1391 | } else | |
1392 | tag_len = 4; | |
1393 | ||
15c45f7b | 1394 | buffer[0] = CIPSO_V4_TAG_ENUM; |
654bbc2a PM |
1395 | buffer[1] = tag_len; |
1396 | buffer[3] = level; | |
1397 | ||
1398 | return tag_len; | |
1399 | } | |
1400 | ||
1401 | /** | |
1402 | * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag | |
1403 | * @doi_def: the DOI definition | |
1404 | * @tag: the CIPSO tag | |
1405 | * @secattr: the security attributes | |
1406 | * | |
1407 | * Description: | |
1408 | * Parse a CIPSO enumerated tag (tag type #2) and return the security | |
1409 | * attributes in @secattr. Return zero on success, negatives values on | |
1410 | * failure. | |
1411 | * | |
1412 | */ | |
1413 | static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, | |
1414 | const unsigned char *tag, | |
1415 | struct netlbl_lsm_secattr *secattr) | |
1416 | { | |
1417 | int ret_val; | |
1418 | u8 tag_len = tag[1]; | |
1419 | u32 level; | |
1420 | ||
1421 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1422 | if (ret_val != 0) | |
1423 | return ret_val; | |
16efd454 | 1424 | secattr->attr.mls.lvl = level; |
654bbc2a PM |
1425 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1426 | ||
1427 | if (tag_len > 4) { | |
654bbc2a PM |
1428 | ret_val = cipso_v4_map_cat_enum_ntoh(doi_def, |
1429 | &tag[4], | |
1430 | tag_len - 4, | |
1431 | secattr); | |
1432 | if (ret_val != 0) { | |
4fbe63d1 | 1433 | netlbl_catmap_free(secattr->attr.mls.cat); |
654bbc2a PM |
1434 | return ret_val; |
1435 | } | |
1436 | ||
1437 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1438 | } | |
1439 | ||
1440 | return 0; | |
1441 | } | |
1442 | ||
484b3669 PM |
1443 | /** |
1444 | * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) | |
1445 | * @doi_def: the DOI definition | |
1446 | * @secattr: the security attributes | |
1447 | * @buffer: the option buffer | |
1448 | * @buffer_len: length of buffer in bytes | |
1449 | * | |
1450 | * Description: | |
1451 | * Generate a CIPSO option using the ranged tag, tag type #5. Returns the | |
1452 | * size of the tag on success, negative values on failure. | |
1453 | * | |
1454 | */ | |
1455 | static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, | |
1456 | const struct netlbl_lsm_secattr *secattr, | |
1457 | unsigned char *buffer, | |
1458 | u32 buffer_len) | |
1459 | { | |
1460 | int ret_val; | |
1461 | u32 tag_len; | |
1462 | u32 level; | |
1463 | ||
1464 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1465 | return -EPERM; | |
1466 | ||
16efd454 PM |
1467 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1468 | secattr->attr.mls.lvl, | |
1469 | &level); | |
484b3669 PM |
1470 | if (ret_val != 0) |
1471 | return ret_val; | |
1472 | ||
1473 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1474 | ret_val = cipso_v4_map_cat_rng_hton(doi_def, | |
1475 | secattr, | |
1476 | &buffer[4], | |
1477 | buffer_len - 4); | |
1478 | if (ret_val < 0) | |
1479 | return ret_val; | |
1480 | ||
1481 | tag_len = 4 + ret_val; | |
1482 | } else | |
1483 | tag_len = 4; | |
1484 | ||
15c45f7b | 1485 | buffer[0] = CIPSO_V4_TAG_RANGE; |
484b3669 PM |
1486 | buffer[1] = tag_len; |
1487 | buffer[3] = level; | |
1488 | ||
1489 | return tag_len; | |
1490 | } | |
1491 | ||
1492 | /** | |
1493 | * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag | |
1494 | * @doi_def: the DOI definition | |
1495 | * @tag: the CIPSO tag | |
1496 | * @secattr: the security attributes | |
1497 | * | |
1498 | * Description: | |
1499 | * Parse a CIPSO ranged tag (tag type #5) and return the security attributes | |
1500 | * in @secattr. Return zero on success, negatives values on failure. | |
1501 | * | |
1502 | */ | |
1503 | static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, | |
1504 | const unsigned char *tag, | |
1505 | struct netlbl_lsm_secattr *secattr) | |
1506 | { | |
1507 | int ret_val; | |
1508 | u8 tag_len = tag[1]; | |
1509 | u32 level; | |
1510 | ||
1511 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1512 | if (ret_val != 0) | |
1513 | return ret_val; | |
16efd454 | 1514 | secattr->attr.mls.lvl = level; |
484b3669 PM |
1515 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1516 | ||
1517 | if (tag_len > 4) { | |
484b3669 PM |
1518 | ret_val = cipso_v4_map_cat_rng_ntoh(doi_def, |
1519 | &tag[4], | |
1520 | tag_len - 4, | |
1521 | secattr); | |
1522 | if (ret_val != 0) { | |
4fbe63d1 | 1523 | netlbl_catmap_free(secattr->attr.mls.cat); |
484b3669 PM |
1524 | return ret_val; |
1525 | } | |
1526 | ||
1527 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1528 | } | |
1529 | ||
1530 | return 0; | |
1531 | } | |
1532 | ||
15c45f7b PM |
1533 | /** |
1534 | * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard) | |
1535 | * @doi_def: the DOI definition | |
1536 | * @secattr: the security attributes | |
1537 | * @buffer: the option buffer | |
1538 | * @buffer_len: length of buffer in bytes | |
1539 | * | |
1540 | * Description: | |
1541 | * Generate a CIPSO option using the local tag. Returns the size of the tag | |
1542 | * on success, negative values on failure. | |
1543 | * | |
1544 | */ | |
1545 | static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def, | |
1546 | const struct netlbl_lsm_secattr *secattr, | |
1547 | unsigned char *buffer, | |
1548 | u32 buffer_len) | |
1549 | { | |
1550 | if (!(secattr->flags & NETLBL_SECATTR_SECID)) | |
1551 | return -EPERM; | |
1552 | ||
1553 | buffer[0] = CIPSO_V4_TAG_LOCAL; | |
1554 | buffer[1] = CIPSO_V4_TAG_LOC_BLEN; | |
1555 | *(u32 *)&buffer[2] = secattr->attr.secid; | |
1556 | ||
1557 | return CIPSO_V4_TAG_LOC_BLEN; | |
1558 | } | |
1559 | ||
1560 | /** | |
1561 | * cipso_v4_parsetag_loc - Parse a CIPSO local tag | |
1562 | * @doi_def: the DOI definition | |
1563 | * @tag: the CIPSO tag | |
1564 | * @secattr: the security attributes | |
1565 | * | |
1566 | * Description: | |
1567 | * Parse a CIPSO local tag and return the security attributes in @secattr. | |
1568 | * Return zero on success, negatives values on failure. | |
1569 | * | |
1570 | */ | |
1571 | static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def, | |
1572 | const unsigned char *tag, | |
1573 | struct netlbl_lsm_secattr *secattr) | |
1574 | { | |
1575 | secattr->attr.secid = *(u32 *)&tag[2]; | |
1576 | secattr->flags |= NETLBL_SECATTR_SECID; | |
1577 | ||
1578 | return 0; | |
1579 | } | |
1580 | ||
446fda4f PM |
1581 | /** |
1582 | * cipso_v4_validate - Validate a CIPSO option | |
1583 | * @option: the start of the option, on error it is set to point to the error | |
1584 | * | |
1585 | * Description: | |
1586 | * This routine is called to validate a CIPSO option, it checks all of the | |
1587 | * fields to ensure that they are at least valid, see the draft snippet below | |
1588 | * for details. If the option is valid then a zero value is returned and | |
1589 | * the value of @option is unchanged. If the option is invalid then a | |
1590 | * non-zero value is returned and @option is adjusted to point to the | |
1591 | * offending portion of the option. From the IETF draft ... | |
1592 | * | |
1593 | * "If any field within the CIPSO options, such as the DOI identifier, is not | |
1594 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' | |
1595 | * (type 12) is generated and returned. The ICMP code field is set to 'bad | |
1596 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field | |
1597 | * that is unrecognized." | |
1598 | * | |
1599 | */ | |
15c45f7b | 1600 | int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) |
446fda4f PM |
1601 | { |
1602 | unsigned char *opt = *option; | |
1603 | unsigned char *tag; | |
1604 | unsigned char opt_iter; | |
1605 | unsigned char err_offset = 0; | |
1606 | u8 opt_len; | |
1607 | u8 tag_len; | |
1608 | struct cipso_v4_doi *doi_def = NULL; | |
1609 | u32 tag_iter; | |
1610 | ||
1611 | /* caller already checks for length values that are too large */ | |
1612 | opt_len = opt[1]; | |
1613 | if (opt_len < 8) { | |
1614 | err_offset = 1; | |
1615 | goto validate_return; | |
1616 | } | |
1617 | ||
1618 | rcu_read_lock(); | |
d3e2ce3b | 1619 | doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2])); |
446fda4f PM |
1620 | if (doi_def == NULL) { |
1621 | err_offset = 2; | |
1622 | goto validate_return_locked; | |
1623 | } | |
1624 | ||
15c45f7b | 1625 | opt_iter = CIPSO_V4_HDR_LEN; |
446fda4f PM |
1626 | tag = opt + opt_iter; |
1627 | while (opt_iter < opt_len) { | |
1628 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) | |
1629 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || | |
1630 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { | |
1631 | err_offset = opt_iter; | |
1632 | goto validate_return_locked; | |
1633 | } | |
1634 | ||
1635 | tag_len = tag[1]; | |
1636 | if (tag_len > (opt_len - opt_iter)) { | |
1637 | err_offset = opt_iter + 1; | |
1638 | goto validate_return_locked; | |
1639 | } | |
1640 | ||
1641 | switch (tag[0]) { | |
1642 | case CIPSO_V4_TAG_RBITMAP: | |
15c45f7b | 1643 | if (tag_len < CIPSO_V4_TAG_RBM_BLEN) { |
446fda4f PM |
1644 | err_offset = opt_iter + 1; |
1645 | goto validate_return_locked; | |
1646 | } | |
1647 | ||
1648 | /* We are already going to do all the verification | |
1649 | * necessary at the socket layer so from our point of | |
1650 | * view it is safe to turn these checks off (and less | |
1651 | * work), however, the CIPSO draft says we should do | |
1652 | * all the CIPSO validations here but it doesn't | |
1653 | * really specify _exactly_ what we need to validate | |
1654 | * ... so, just make it a sysctl tunable. */ | |
1655 | if (cipso_v4_rbm_strictvalid) { | |
1656 | if (cipso_v4_map_lvl_valid(doi_def, | |
1657 | tag[3]) < 0) { | |
1658 | err_offset = opt_iter + 3; | |
1659 | goto validate_return_locked; | |
1660 | } | |
15c45f7b | 1661 | if (tag_len > CIPSO_V4_TAG_RBM_BLEN && |
446fda4f PM |
1662 | cipso_v4_map_cat_rbm_valid(doi_def, |
1663 | &tag[4], | |
1664 | tag_len - 4) < 0) { | |
1665 | err_offset = opt_iter + 4; | |
1666 | goto validate_return_locked; | |
1667 | } | |
1668 | } | |
1669 | break; | |
654bbc2a | 1670 | case CIPSO_V4_TAG_ENUM: |
15c45f7b | 1671 | if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) { |
654bbc2a PM |
1672 | err_offset = opt_iter + 1; |
1673 | goto validate_return_locked; | |
1674 | } | |
1675 | ||
1676 | if (cipso_v4_map_lvl_valid(doi_def, | |
1677 | tag[3]) < 0) { | |
1678 | err_offset = opt_iter + 3; | |
1679 | goto validate_return_locked; | |
1680 | } | |
15c45f7b | 1681 | if (tag_len > CIPSO_V4_TAG_ENUM_BLEN && |
654bbc2a PM |
1682 | cipso_v4_map_cat_enum_valid(doi_def, |
1683 | &tag[4], | |
1684 | tag_len - 4) < 0) { | |
1685 | err_offset = opt_iter + 4; | |
1686 | goto validate_return_locked; | |
1687 | } | |
1688 | break; | |
484b3669 | 1689 | case CIPSO_V4_TAG_RANGE: |
15c45f7b | 1690 | if (tag_len < CIPSO_V4_TAG_RNG_BLEN) { |
484b3669 PM |
1691 | err_offset = opt_iter + 1; |
1692 | goto validate_return_locked; | |
1693 | } | |
1694 | ||
1695 | if (cipso_v4_map_lvl_valid(doi_def, | |
1696 | tag[3]) < 0) { | |
1697 | err_offset = opt_iter + 3; | |
1698 | goto validate_return_locked; | |
1699 | } | |
15c45f7b | 1700 | if (tag_len > CIPSO_V4_TAG_RNG_BLEN && |
484b3669 PM |
1701 | cipso_v4_map_cat_rng_valid(doi_def, |
1702 | &tag[4], | |
1703 | tag_len - 4) < 0) { | |
1704 | err_offset = opt_iter + 4; | |
1705 | goto validate_return_locked; | |
1706 | } | |
1707 | break; | |
15c45f7b PM |
1708 | case CIPSO_V4_TAG_LOCAL: |
1709 | /* This is a non-standard tag that we only allow for | |
1710 | * local connections, so if the incoming interface is | |
89d7ae34 PM |
1711 | * not the loopback device drop the packet. Further, |
1712 | * there is no legitimate reason for setting this from | |
1713 | * userspace so reject it if skb is NULL. */ | |
1714 | if (skb == NULL || !(skb->dev->flags & IFF_LOOPBACK)) { | |
15c45f7b PM |
1715 | err_offset = opt_iter; |
1716 | goto validate_return_locked; | |
1717 | } | |
1718 | if (tag_len != CIPSO_V4_TAG_LOC_BLEN) { | |
1719 | err_offset = opt_iter + 1; | |
1720 | goto validate_return_locked; | |
1721 | } | |
1722 | break; | |
446fda4f PM |
1723 | default: |
1724 | err_offset = opt_iter; | |
1725 | goto validate_return_locked; | |
1726 | } | |
1727 | ||
1728 | tag += tag_len; | |
1729 | opt_iter += tag_len; | |
1730 | } | |
1731 | ||
1732 | validate_return_locked: | |
1733 | rcu_read_unlock(); | |
1734 | validate_return: | |
1735 | *option = opt + err_offset; | |
1736 | return err_offset; | |
1737 | } | |
1738 | ||
1739 | /** | |
25985edc | 1740 | * cipso_v4_error - Send the correct response for a bad packet |
446fda4f PM |
1741 | * @skb: the packet |
1742 | * @error: the error code | |
1743 | * @gateway: CIPSO gateway flag | |
1744 | * | |
1745 | * Description: | |
1746 | * Based on the error code given in @error, send an ICMP error message back to | |
1747 | * the originating host. From the IETF draft ... | |
1748 | * | |
1749 | * "If the contents of the CIPSO [option] are valid but the security label is | |
1750 | * outside of the configured host or port label range, the datagram is | |
1751 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and | |
1752 | * returned. The code field of the ICMP is set to 'communication with | |
1753 | * destination network administratively prohibited' (code 9) or to | |
1754 | * 'communication with destination host administratively prohibited' | |
1755 | * (code 10). The value of the code is dependent on whether the originator | |
1756 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The | |
1757 | * recipient of the ICMP message MUST be able to handle either value. The | |
1758 | * same procedure is performed if a CIPSO [option] can not be added to an | |
1759 | * IP packet because it is too large to fit in the IP options area." | |
1760 | * | |
1761 | * "If the error is triggered by receipt of an ICMP message, the message is | |
1762 | * discarded and no response is permitted (consistent with general ICMP | |
1763 | * processing rules)." | |
1764 | * | |
1765 | */ | |
1766 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) | |
1767 | { | |
eddc9ec5 | 1768 | if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) |
446fda4f PM |
1769 | return; |
1770 | ||
1771 | if (gateway) | |
1772 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0); | |
1773 | else | |
1774 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0); | |
1775 | } | |
1776 | ||
1777 | /** | |
948bf85c PM |
1778 | * cipso_v4_genopt - Generate a CIPSO option |
1779 | * @buf: the option buffer | |
1780 | * @buf_len: the size of opt_buf | |
446fda4f | 1781 | * @doi_def: the CIPSO DOI to use |
948bf85c | 1782 | * @secattr: the security attributes |
446fda4f PM |
1783 | * |
1784 | * Description: | |
948bf85c PM |
1785 | * Generate a CIPSO option using the DOI definition and security attributes |
1786 | * passed to the function. Returns the length of the option on success and | |
1787 | * negative values on failure. | |
446fda4f PM |
1788 | * |
1789 | */ | |
948bf85c PM |
1790 | static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, |
1791 | const struct cipso_v4_doi *doi_def, | |
1792 | const struct netlbl_lsm_secattr *secattr) | |
446fda4f | 1793 | { |
948bf85c | 1794 | int ret_val; |
446fda4f | 1795 | u32 iter; |
446fda4f | 1796 | |
948bf85c PM |
1797 | if (buf_len <= CIPSO_V4_HDR_LEN) |
1798 | return -ENOSPC; | |
91b1ed0a | 1799 | |
446fda4f PM |
1800 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1801 | * really a good assumption to make but since we only support the MAC | |
1802 | * tags right now it is a safe assumption. */ | |
1803 | iter = 0; | |
1804 | do { | |
91b1ed0a | 1805 | memset(buf, 0, buf_len); |
446fda4f PM |
1806 | switch (doi_def->tags[iter]) { |
1807 | case CIPSO_V4_TAG_RBITMAP: | |
1808 | ret_val = cipso_v4_gentag_rbm(doi_def, | |
91b1ed0a PM |
1809 | secattr, |
1810 | &buf[CIPSO_V4_HDR_LEN], | |
1811 | buf_len - CIPSO_V4_HDR_LEN); | |
446fda4f | 1812 | break; |
654bbc2a PM |
1813 | case CIPSO_V4_TAG_ENUM: |
1814 | ret_val = cipso_v4_gentag_enum(doi_def, | |
1815 | secattr, | |
1816 | &buf[CIPSO_V4_HDR_LEN], | |
1817 | buf_len - CIPSO_V4_HDR_LEN); | |
1818 | break; | |
484b3669 PM |
1819 | case CIPSO_V4_TAG_RANGE: |
1820 | ret_val = cipso_v4_gentag_rng(doi_def, | |
1821 | secattr, | |
1822 | &buf[CIPSO_V4_HDR_LEN], | |
1823 | buf_len - CIPSO_V4_HDR_LEN); | |
1824 | break; | |
15c45f7b PM |
1825 | case CIPSO_V4_TAG_LOCAL: |
1826 | ret_val = cipso_v4_gentag_loc(doi_def, | |
1827 | secattr, | |
1828 | &buf[CIPSO_V4_HDR_LEN], | |
1829 | buf_len - CIPSO_V4_HDR_LEN); | |
1830 | break; | |
446fda4f | 1831 | default: |
948bf85c | 1832 | return -EPERM; |
446fda4f PM |
1833 | } |
1834 | ||
1835 | iter++; | |
91b1ed0a | 1836 | } while (ret_val < 0 && |
446fda4f PM |
1837 | iter < CIPSO_V4_TAG_MAXCNT && |
1838 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); | |
91b1ed0a | 1839 | if (ret_val < 0) |
948bf85c | 1840 | return ret_val; |
91b1ed0a | 1841 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
948bf85c PM |
1842 | return CIPSO_V4_HDR_LEN + ret_val; |
1843 | } | |
1844 | ||
1845 | /** | |
1846 | * cipso_v4_sock_setattr - Add a CIPSO option to a socket | |
1847 | * @sk: the socket | |
1848 | * @doi_def: the CIPSO DOI to use | |
1849 | * @secattr: the specific security attributes of the socket | |
1850 | * | |
1851 | * Description: | |
1852 | * Set the CIPSO option on the given socket using the DOI definition and | |
1853 | * security attributes passed to the function. This function requires | |
1854 | * exclusive access to @sk, which means it either needs to be in the | |
1855 | * process of being created or locked. Returns zero on success and negative | |
1856 | * values on failure. | |
1857 | * | |
1858 | */ | |
1859 | int cipso_v4_sock_setattr(struct sock *sk, | |
1860 | const struct cipso_v4_doi *doi_def, | |
1861 | const struct netlbl_lsm_secattr *secattr) | |
1862 | { | |
1863 | int ret_val = -EPERM; | |
1864 | unsigned char *buf = NULL; | |
1865 | u32 buf_len; | |
1866 | u32 opt_len; | |
f6d8bd05 | 1867 | struct ip_options_rcu *old, *opt = NULL; |
948bf85c PM |
1868 | struct inet_sock *sk_inet; |
1869 | struct inet_connection_sock *sk_conn; | |
1870 | ||
1871 | /* In the case of sock_create_lite(), the sock->sk field is not | |
1872 | * defined yet but it is not a problem as the only users of these | |
1873 | * "lite" PF_INET sockets are functions which do an accept() call | |
1874 | * afterwards so we will label the socket as part of the accept(). */ | |
1875 | if (sk == NULL) | |
1876 | return 0; | |
1877 | ||
1878 | /* We allocate the maximum CIPSO option size here so we are probably | |
1879 | * being a little wasteful, but it makes our life _much_ easier later | |
1880 | * on and after all we are only talking about 40 bytes. */ | |
1881 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1882 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
1883 | if (buf == NULL) { | |
1884 | ret_val = -ENOMEM; | |
1885 | goto socket_setattr_failure; | |
1886 | } | |
1887 | ||
1888 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1889 | if (ret_val < 0) | |
1890 | goto socket_setattr_failure; | |
1891 | buf_len = ret_val; | |
446fda4f PM |
1892 | |
1893 | /* We can't use ip_options_get() directly because it makes a call to | |
1894 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
f8687afe PM |
1895 | * we won't always have CAP_NET_RAW even though we _always_ want to |
1896 | * set the IPOPT_CIPSO option. */ | |
446fda4f PM |
1897 | opt_len = (buf_len + 3) & ~3; |
1898 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
1899 | if (opt == NULL) { | |
1900 | ret_val = -ENOMEM; | |
1901 | goto socket_setattr_failure; | |
1902 | } | |
f6d8bd05 ED |
1903 | memcpy(opt->opt.__data, buf, buf_len); |
1904 | opt->opt.optlen = opt_len; | |
1905 | opt->opt.cipso = sizeof(struct iphdr); | |
446fda4f PM |
1906 | kfree(buf); |
1907 | buf = NULL; | |
446fda4f PM |
1908 | |
1909 | sk_inet = inet_sk(sk); | |
f6d8bd05 ED |
1910 | |
1911 | old = rcu_dereference_protected(sk_inet->inet_opt, sock_owned_by_user(sk)); | |
446fda4f PM |
1912 | if (sk_inet->is_icsk) { |
1913 | sk_conn = inet_csk(sk); | |
f6d8bd05 ED |
1914 | if (old) |
1915 | sk_conn->icsk_ext_hdr_len -= old->opt.optlen; | |
1916 | sk_conn->icsk_ext_hdr_len += opt->opt.optlen; | |
446fda4f PM |
1917 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); |
1918 | } | |
f6d8bd05 ED |
1919 | rcu_assign_pointer(sk_inet->inet_opt, opt); |
1920 | if (old) | |
4f9c8c1b | 1921 | kfree_rcu(old, rcu); |
446fda4f PM |
1922 | |
1923 | return 0; | |
1924 | ||
1925 | socket_setattr_failure: | |
1926 | kfree(buf); | |
1927 | kfree(opt); | |
1928 | return ret_val; | |
1929 | } | |
1930 | ||
014ab19a | 1931 | /** |
389fb800 PM |
1932 | * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket |
1933 | * @req: the connection request socket | |
1934 | * @doi_def: the CIPSO DOI to use | |
1935 | * @secattr: the specific security attributes of the socket | |
014ab19a PM |
1936 | * |
1937 | * Description: | |
389fb800 PM |
1938 | * Set the CIPSO option on the given socket using the DOI definition and |
1939 | * security attributes passed to the function. Returns zero on success and | |
1940 | * negative values on failure. | |
014ab19a PM |
1941 | * |
1942 | */ | |
389fb800 PM |
1943 | int cipso_v4_req_setattr(struct request_sock *req, |
1944 | const struct cipso_v4_doi *doi_def, | |
1945 | const struct netlbl_lsm_secattr *secattr) | |
014ab19a | 1946 | { |
389fb800 PM |
1947 | int ret_val = -EPERM; |
1948 | unsigned char *buf = NULL; | |
1949 | u32 buf_len; | |
1950 | u32 opt_len; | |
f6d8bd05 | 1951 | struct ip_options_rcu *opt = NULL; |
389fb800 | 1952 | struct inet_request_sock *req_inet; |
014ab19a | 1953 | |
389fb800 PM |
1954 | /* We allocate the maximum CIPSO option size here so we are probably |
1955 | * being a little wasteful, but it makes our life _much_ easier later | |
1956 | * on and after all we are only talking about 40 bytes. */ | |
1957 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1958 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
1959 | if (buf == NULL) { | |
1960 | ret_val = -ENOMEM; | |
1961 | goto req_setattr_failure; | |
1962 | } | |
1963 | ||
1964 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1965 | if (ret_val < 0) | |
1966 | goto req_setattr_failure; | |
1967 | buf_len = ret_val; | |
1968 | ||
1969 | /* We can't use ip_options_get() directly because it makes a call to | |
1970 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
1971 | * we won't always have CAP_NET_RAW even though we _always_ want to | |
1972 | * set the IPOPT_CIPSO option. */ | |
1973 | opt_len = (buf_len + 3) & ~3; | |
1974 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
1975 | if (opt == NULL) { | |
1976 | ret_val = -ENOMEM; | |
1977 | goto req_setattr_failure; | |
1978 | } | |
f6d8bd05 ED |
1979 | memcpy(opt->opt.__data, buf, buf_len); |
1980 | opt->opt.optlen = opt_len; | |
1981 | opt->opt.cipso = sizeof(struct iphdr); | |
389fb800 PM |
1982 | kfree(buf); |
1983 | buf = NULL; | |
1984 | ||
1985 | req_inet = inet_rsk(req); | |
1986 | opt = xchg(&req_inet->opt, opt); | |
f6d8bd05 | 1987 | if (opt) |
4f9c8c1b | 1988 | kfree_rcu(opt, rcu); |
389fb800 PM |
1989 | |
1990 | return 0; | |
1991 | ||
1992 | req_setattr_failure: | |
1993 | kfree(buf); | |
1994 | kfree(opt); | |
1995 | return ret_val; | |
1996 | } | |
1997 | ||
1998 | /** | |
1999 | * cipso_v4_delopt - Delete the CIPSO option from a set of IP options | |
2000 | * @opt_ptr: IP option pointer | |
2001 | * | |
2002 | * Description: | |
2003 | * Deletes the CIPSO IP option from a set of IP options and makes the necessary | |
2004 | * adjustments to the IP option structure. Returns zero on success, negative | |
2005 | * values on failure. | |
2006 | * | |
2007 | */ | |
f6d8bd05 | 2008 | static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr) |
389fb800 PM |
2009 | { |
2010 | int hdr_delta = 0; | |
f6d8bd05 | 2011 | struct ip_options_rcu *opt = *opt_ptr; |
014ab19a | 2012 | |
f6d8bd05 | 2013 | if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) { |
014ab19a PM |
2014 | u8 cipso_len; |
2015 | u8 cipso_off; | |
2016 | unsigned char *cipso_ptr; | |
2017 | int iter; | |
2018 | int optlen_new; | |
2019 | ||
f6d8bd05 ED |
2020 | cipso_off = opt->opt.cipso - sizeof(struct iphdr); |
2021 | cipso_ptr = &opt->opt.__data[cipso_off]; | |
014ab19a PM |
2022 | cipso_len = cipso_ptr[1]; |
2023 | ||
f6d8bd05 ED |
2024 | if (opt->opt.srr > opt->opt.cipso) |
2025 | opt->opt.srr -= cipso_len; | |
2026 | if (opt->opt.rr > opt->opt.cipso) | |
2027 | opt->opt.rr -= cipso_len; | |
2028 | if (opt->opt.ts > opt->opt.cipso) | |
2029 | opt->opt.ts -= cipso_len; | |
2030 | if (opt->opt.router_alert > opt->opt.cipso) | |
2031 | opt->opt.router_alert -= cipso_len; | |
2032 | opt->opt.cipso = 0; | |
014ab19a PM |
2033 | |
2034 | memmove(cipso_ptr, cipso_ptr + cipso_len, | |
f6d8bd05 | 2035 | opt->opt.optlen - cipso_off - cipso_len); |
014ab19a PM |
2036 | |
2037 | /* determining the new total option length is tricky because of | |
2038 | * the padding necessary, the only thing i can think to do at | |
2039 | * this point is walk the options one-by-one, skipping the | |
2040 | * padding at the end to determine the actual option size and | |
2041 | * from there we can determine the new total option length */ | |
2042 | iter = 0; | |
2043 | optlen_new = 0; | |
f6d8bd05 ED |
2044 | while (iter < opt->opt.optlen) |
2045 | if (opt->opt.__data[iter] != IPOPT_NOP) { | |
2046 | iter += opt->opt.__data[iter + 1]; | |
014ab19a PM |
2047 | optlen_new = iter; |
2048 | } else | |
2049 | iter++; | |
f6d8bd05 ED |
2050 | hdr_delta = opt->opt.optlen; |
2051 | opt->opt.optlen = (optlen_new + 3) & ~3; | |
2052 | hdr_delta -= opt->opt.optlen; | |
014ab19a PM |
2053 | } else { |
2054 | /* only the cipso option was present on the socket so we can | |
2055 | * remove the entire option struct */ | |
389fb800 | 2056 | *opt_ptr = NULL; |
f6d8bd05 | 2057 | hdr_delta = opt->opt.optlen; |
4f9c8c1b | 2058 | kfree_rcu(opt, rcu); |
014ab19a PM |
2059 | } |
2060 | ||
389fb800 PM |
2061 | return hdr_delta; |
2062 | } | |
2063 | ||
2064 | /** | |
2065 | * cipso_v4_sock_delattr - Delete the CIPSO option from a socket | |
2066 | * @sk: the socket | |
2067 | * | |
2068 | * Description: | |
2069 | * Removes the CIPSO option from a socket, if present. | |
2070 | * | |
2071 | */ | |
2072 | void cipso_v4_sock_delattr(struct sock *sk) | |
2073 | { | |
2074 | int hdr_delta; | |
f6d8bd05 | 2075 | struct ip_options_rcu *opt; |
389fb800 PM |
2076 | struct inet_sock *sk_inet; |
2077 | ||
2078 | sk_inet = inet_sk(sk); | |
f6d8bd05 ED |
2079 | opt = rcu_dereference_protected(sk_inet->inet_opt, 1); |
2080 | if (opt == NULL || opt->opt.cipso == 0) | |
389fb800 PM |
2081 | return; |
2082 | ||
f6d8bd05 | 2083 | hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt); |
014ab19a PM |
2084 | if (sk_inet->is_icsk && hdr_delta > 0) { |
2085 | struct inet_connection_sock *sk_conn = inet_csk(sk); | |
2086 | sk_conn->icsk_ext_hdr_len -= hdr_delta; | |
2087 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
2088 | } | |
2089 | } | |
2090 | ||
389fb800 PM |
2091 | /** |
2092 | * cipso_v4_req_delattr - Delete the CIPSO option from a request socket | |
2093 | * @reg: the request socket | |
2094 | * | |
2095 | * Description: | |
2096 | * Removes the CIPSO option from a request socket, if present. | |
2097 | * | |
2098 | */ | |
2099 | void cipso_v4_req_delattr(struct request_sock *req) | |
2100 | { | |
f6d8bd05 | 2101 | struct ip_options_rcu *opt; |
389fb800 PM |
2102 | struct inet_request_sock *req_inet; |
2103 | ||
2104 | req_inet = inet_rsk(req); | |
2105 | opt = req_inet->opt; | |
f6d8bd05 | 2106 | if (opt == NULL || opt->opt.cipso == 0) |
389fb800 PM |
2107 | return; |
2108 | ||
2109 | cipso_v4_delopt(&req_inet->opt); | |
2110 | } | |
2111 | ||
446fda4f | 2112 | /** |
63d804ea PM |
2113 | * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions |
2114 | * @cipso: the CIPSO v4 option | |
446fda4f PM |
2115 | * @secattr: the security attributes |
2116 | * | |
2117 | * Description: | |
63d804ea PM |
2118 | * Inspect @cipso and return the security attributes in @secattr. Returns zero |
2119 | * on success and negative values on failure. | |
446fda4f PM |
2120 | * |
2121 | */ | |
63d804ea PM |
2122 | static int cipso_v4_getattr(const unsigned char *cipso, |
2123 | struct netlbl_lsm_secattr *secattr) | |
446fda4f PM |
2124 | { |
2125 | int ret_val = -ENOMSG; | |
446fda4f PM |
2126 | u32 doi; |
2127 | struct cipso_v4_doi *doi_def; | |
2128 | ||
63d804ea PM |
2129 | if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0) |
2130 | return 0; | |
446fda4f | 2131 | |
d3e2ce3b | 2132 | doi = get_unaligned_be32(&cipso[2]); |
446fda4f | 2133 | rcu_read_lock(); |
9bb5fd2b | 2134 | doi_def = cipso_v4_doi_search(doi); |
63d804ea PM |
2135 | if (doi_def == NULL) |
2136 | goto getattr_return; | |
91b1ed0a PM |
2137 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
2138 | * really a good assumption to make but since we only support the MAC | |
2139 | * tags right now it is a safe assumption. */ | |
63d804ea | 2140 | switch (cipso[6]) { |
446fda4f | 2141 | case CIPSO_V4_TAG_RBITMAP: |
63d804ea | 2142 | ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr); |
446fda4f | 2143 | break; |
654bbc2a | 2144 | case CIPSO_V4_TAG_ENUM: |
63d804ea | 2145 | ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr); |
654bbc2a | 2146 | break; |
484b3669 | 2147 | case CIPSO_V4_TAG_RANGE: |
63d804ea | 2148 | ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr); |
484b3669 | 2149 | break; |
15c45f7b PM |
2150 | case CIPSO_V4_TAG_LOCAL: |
2151 | ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr); | |
2152 | break; | |
446fda4f | 2153 | } |
16efd454 PM |
2154 | if (ret_val == 0) |
2155 | secattr->type = NETLBL_NLTYPE_CIPSOV4; | |
446fda4f | 2156 | |
63d804ea PM |
2157 | getattr_return: |
2158 | rcu_read_unlock(); | |
14a72f53 PM |
2159 | return ret_val; |
2160 | } | |
2161 | ||
63d804ea PM |
2162 | /** |
2163 | * cipso_v4_sock_getattr - Get the security attributes from a sock | |
2164 | * @sk: the sock | |
2165 | * @secattr: the security attributes | |
2166 | * | |
2167 | * Description: | |
2168 | * Query @sk to see if there is a CIPSO option attached to the sock and if | |
2169 | * there is return the CIPSO security attributes in @secattr. This function | |
2170 | * requires that @sk be locked, or privately held, but it does not do any | |
2171 | * locking itself. Returns zero on success and negative values on failure. | |
2172 | * | |
2173 | */ | |
2174 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) | |
2175 | { | |
f6d8bd05 ED |
2176 | struct ip_options_rcu *opt; |
2177 | int res = -ENOMSG; | |
63d804ea | 2178 | |
f6d8bd05 ED |
2179 | rcu_read_lock(); |
2180 | opt = rcu_dereference(inet_sk(sk)->inet_opt); | |
2181 | if (opt && opt->opt.cipso) | |
2182 | res = cipso_v4_getattr(opt->opt.__data + | |
2183 | opt->opt.cipso - | |
2184 | sizeof(struct iphdr), | |
2185 | secattr); | |
2186 | rcu_read_unlock(); | |
2187 | return res; | |
63d804ea PM |
2188 | } |
2189 | ||
948bf85c PM |
2190 | /** |
2191 | * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet | |
2192 | * @skb: the packet | |
2193 | * @secattr: the security attributes | |
2194 | * | |
2195 | * Description: | |
2196 | * Set the CIPSO option on the given packet based on the security attributes. | |
2197 | * Returns a pointer to the IP header on success and NULL on failure. | |
2198 | * | |
2199 | */ | |
2200 | int cipso_v4_skbuff_setattr(struct sk_buff *skb, | |
2201 | const struct cipso_v4_doi *doi_def, | |
2202 | const struct netlbl_lsm_secattr *secattr) | |
2203 | { | |
2204 | int ret_val; | |
2205 | struct iphdr *iph; | |
2206 | struct ip_options *opt = &IPCB(skb)->opt; | |
2207 | unsigned char buf[CIPSO_V4_OPT_LEN_MAX]; | |
2208 | u32 buf_len = CIPSO_V4_OPT_LEN_MAX; | |
2209 | u32 opt_len; | |
2210 | int len_delta; | |
2211 | ||
00af5c69 | 2212 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); |
2213 | if (ret_val < 0) | |
2214 | return ret_val; | |
2215 | buf_len = ret_val; | |
948bf85c PM |
2216 | opt_len = (buf_len + 3) & ~3; |
2217 | ||
2218 | /* we overwrite any existing options to ensure that we have enough | |
2219 | * room for the CIPSO option, the reason is that we _need_ to guarantee | |
2220 | * that the security label is applied to the packet - we do the same | |
2221 | * thing when using the socket options and it hasn't caused a problem, | |
2222 | * if we need to we can always revisit this choice later */ | |
2223 | ||
2224 | len_delta = opt_len - opt->optlen; | |
2225 | /* if we don't ensure enough headroom we could panic on the skb_push() | |
2226 | * call below so make sure we have enough, we are also "mangling" the | |
2227 | * packet so we should probably do a copy-on-write call anyway */ | |
2228 | ret_val = skb_cow(skb, skb_headroom(skb) + len_delta); | |
2229 | if (ret_val < 0) | |
2230 | return ret_val; | |
2231 | ||
2232 | if (len_delta > 0) { | |
2233 | /* we assume that the header + opt->optlen have already been | |
2234 | * "pushed" in ip_options_build() or similar */ | |
2235 | iph = ip_hdr(skb); | |
2236 | skb_push(skb, len_delta); | |
2237 | memmove((char *)iph - len_delta, iph, iph->ihl << 2); | |
2238 | skb_reset_network_header(skb); | |
2239 | iph = ip_hdr(skb); | |
2240 | } else if (len_delta < 0) { | |
2241 | iph = ip_hdr(skb); | |
2242 | memset(iph + 1, IPOPT_NOP, opt->optlen); | |
2243 | } else | |
2244 | iph = ip_hdr(skb); | |
2245 | ||
2246 | if (opt->optlen > 0) | |
2247 | memset(opt, 0, sizeof(*opt)); | |
2248 | opt->optlen = opt_len; | |
2249 | opt->cipso = sizeof(struct iphdr); | |
2250 | opt->is_changed = 1; | |
2251 | ||
2252 | /* we have to do the following because we are being called from a | |
2253 | * netfilter hook which means the packet already has had the header | |
2254 | * fields populated and the checksum calculated - yes this means we | |
2255 | * are doing more work than needed but we do it to keep the core | |
2256 | * stack clean and tidy */ | |
2257 | memcpy(iph + 1, buf, buf_len); | |
2258 | if (opt_len > buf_len) | |
2259 | memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); | |
2260 | if (len_delta != 0) { | |
2261 | iph->ihl = 5 + (opt_len >> 2); | |
2262 | iph->tot_len = htons(skb->len); | |
2263 | } | |
2264 | ip_send_check(iph); | |
2265 | ||
2266 | return 0; | |
2267 | } | |
2268 | ||
2269 | /** | |
2270 | * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet | |
2271 | * @skb: the packet | |
2272 | * | |
2273 | * Description: | |
2274 | * Removes any and all CIPSO options from the given packet. Returns zero on | |
2275 | * success, negative values on failure. | |
2276 | * | |
2277 | */ | |
2278 | int cipso_v4_skbuff_delattr(struct sk_buff *skb) | |
2279 | { | |
2280 | int ret_val; | |
2281 | struct iphdr *iph; | |
2282 | struct ip_options *opt = &IPCB(skb)->opt; | |
2283 | unsigned char *cipso_ptr; | |
2284 | ||
2285 | if (opt->cipso == 0) | |
2286 | return 0; | |
2287 | ||
2288 | /* since we are changing the packet we should make a copy */ | |
2289 | ret_val = skb_cow(skb, skb_headroom(skb)); | |
2290 | if (ret_val < 0) | |
2291 | return ret_val; | |
2292 | ||
2293 | /* the easiest thing to do is just replace the cipso option with noop | |
2294 | * options since we don't change the size of the packet, although we | |
2295 | * still need to recalculate the checksum */ | |
2296 | ||
2297 | iph = ip_hdr(skb); | |
2298 | cipso_ptr = (unsigned char *)iph + opt->cipso; | |
2299 | memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); | |
2300 | opt->cipso = 0; | |
2301 | opt->is_changed = 1; | |
2302 | ||
2303 | ip_send_check(iph); | |
2304 | ||
2305 | return 0; | |
2306 | } | |
2307 | ||
446fda4f PM |
2308 | /** |
2309 | * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option | |
2310 | * @skb: the packet | |
2311 | * @secattr: the security attributes | |
2312 | * | |
2313 | * Description: | |
2314 | * Parse the given packet's CIPSO option and return the security attributes. | |
2315 | * Returns zero on success and negative values on failure. | |
2316 | * | |
2317 | */ | |
2318 | int cipso_v4_skbuff_getattr(const struct sk_buff *skb, | |
2319 | struct netlbl_lsm_secattr *secattr) | |
2320 | { | |
63d804ea | 2321 | return cipso_v4_getattr(CIPSO_V4_OPTPTR(skb), secattr); |
446fda4f PM |
2322 | } |
2323 | ||
2324 | /* | |
2325 | * Setup Functions | |
2326 | */ | |
2327 | ||
2328 | /** | |
2329 | * cipso_v4_init - Initialize the CIPSO module | |
2330 | * | |
2331 | * Description: | |
2332 | * Initialize the CIPSO module and prepare it for use. Returns zero on success | |
2333 | * and negative values on failure. | |
2334 | * | |
2335 | */ | |
2336 | static int __init cipso_v4_init(void) | |
2337 | { | |
2338 | int ret_val; | |
2339 | ||
2340 | ret_val = cipso_v4_cache_init(); | |
2341 | if (ret_val != 0) | |
2342 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", | |
2343 | ret_val); | |
2344 | ||
2345 | return 0; | |
2346 | } | |
2347 | ||
2348 | subsys_initcall(cipso_v4_init); |