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 | |
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 | ||
446fda4f PM |
137 | /** |
138 | * cipso_v4_cache_entry_free - Frees a cache entry | |
139 | * @entry: the entry to free | |
140 | * | |
141 | * Description: | |
ffb733c6 | 142 | * This function frees the memory associated with a cache entry including the |
143 | * LSM cache data if there are no longer any users, i.e. reference count == 0. | |
446fda4f PM |
144 | * |
145 | */ | |
146 | static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) | |
147 | { | |
ffb733c6 | 148 | if (entry->lsm_data) |
149 | netlbl_secattr_cache_free(entry->lsm_data); | |
446fda4f PM |
150 | kfree(entry->key); |
151 | kfree(entry); | |
152 | } | |
153 | ||
154 | /** | |
155 | * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache | |
156 | * @key: the hash key | |
157 | * @key_len: the length of the key in bytes | |
158 | * | |
159 | * Description: | |
160 | * The CIPSO tag hashing function. Returns a 32-bit hash value. | |
161 | * | |
162 | */ | |
163 | static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) | |
164 | { | |
165 | return jhash(key, key_len, 0); | |
166 | } | |
167 | ||
168 | /* | |
169 | * Label Mapping Cache Functions | |
170 | */ | |
171 | ||
172 | /** | |
173 | * cipso_v4_cache_init - Initialize the CIPSO cache | |
174 | * | |
175 | * Description: | |
176 | * Initializes the CIPSO label mapping cache, this function should be called | |
177 | * before any of the other functions defined in this file. Returns zero on | |
178 | * success, negative values on error. | |
179 | * | |
180 | */ | |
cb57659a | 181 | static int __init cipso_v4_cache_init(void) |
446fda4f PM |
182 | { |
183 | u32 iter; | |
184 | ||
185 | cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS, | |
186 | sizeof(struct cipso_v4_map_cache_bkt), | |
187 | GFP_KERNEL); | |
51456b29 | 188 | if (!cipso_v4_cache) |
446fda4f PM |
189 | return -ENOMEM; |
190 | ||
191 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
192 | spin_lock_init(&cipso_v4_cache[iter].lock); | |
193 | cipso_v4_cache[iter].size = 0; | |
194 | INIT_LIST_HEAD(&cipso_v4_cache[iter].list); | |
195 | } | |
196 | ||
197 | return 0; | |
198 | } | |
199 | ||
200 | /** | |
201 | * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache | |
202 | * | |
203 | * Description: | |
204 | * Invalidates and frees any entries in the CIPSO cache. Returns zero on | |
205 | * success and negative values on failure. | |
206 | * | |
207 | */ | |
208 | void cipso_v4_cache_invalidate(void) | |
209 | { | |
210 | struct cipso_v4_map_cache_entry *entry, *tmp_entry; | |
211 | u32 iter; | |
212 | ||
213 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
609c92fe | 214 | spin_lock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
215 | list_for_each_entry_safe(entry, |
216 | tmp_entry, | |
217 | &cipso_v4_cache[iter].list, list) { | |
218 | list_del(&entry->list); | |
219 | cipso_v4_cache_entry_free(entry); | |
220 | } | |
221 | cipso_v4_cache[iter].size = 0; | |
609c92fe | 222 | spin_unlock_bh(&cipso_v4_cache[iter].lock); |
446fda4f | 223 | } |
446fda4f PM |
224 | } |
225 | ||
226 | /** | |
227 | * cipso_v4_cache_check - Check the CIPSO cache for a label mapping | |
228 | * @key: the buffer to check | |
229 | * @key_len: buffer length in bytes | |
230 | * @secattr: the security attribute struct to use | |
231 | * | |
232 | * Description: | |
233 | * This function checks the cache to see if a label mapping already exists for | |
234 | * the given key. If there is a match then the cache is adjusted and the | |
235 | * @secattr struct is populated with the correct LSM security attributes. The | |
236 | * cache is adjusted in the following manner if the entry is not already the | |
237 | * first in the cache bucket: | |
238 | * | |
239 | * 1. The cache entry's activity counter is incremented | |
240 | * 2. The previous (higher ranking) entry's activity counter is decremented | |
241 | * 3. If the difference between the two activity counters is geater than | |
242 | * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped | |
243 | * | |
244 | * Returns zero on success, -ENOENT for a cache miss, and other negative values | |
245 | * on error. | |
246 | * | |
247 | */ | |
248 | static int cipso_v4_cache_check(const unsigned char *key, | |
249 | u32 key_len, | |
250 | struct netlbl_lsm_secattr *secattr) | |
251 | { | |
252 | u32 bkt; | |
253 | struct cipso_v4_map_cache_entry *entry; | |
254 | struct cipso_v4_map_cache_entry *prev_entry = NULL; | |
255 | u32 hash; | |
256 | ||
257 | if (!cipso_v4_cache_enabled) | |
258 | return -ENOENT; | |
259 | ||
260 | hash = cipso_v4_map_cache_hash(key, key_len); | |
5e0f8923 | 261 | bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 262 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
263 | list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) { |
264 | if (entry->hash == hash && | |
265 | entry->key_len == key_len && | |
266 | memcmp(entry->key, key, key_len) == 0) { | |
267 | entry->activity += 1; | |
b4217b82 | 268 | refcount_inc(&entry->lsm_data->refcount); |
ffb733c6 | 269 | secattr->cache = entry->lsm_data; |
701a90ba | 270 | secattr->flags |= NETLBL_SECATTR_CACHE; |
16efd454 | 271 | secattr->type = NETLBL_NLTYPE_CIPSOV4; |
51456b29 | 272 | if (!prev_entry) { |
609c92fe | 273 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
274 | return 0; |
275 | } | |
276 | ||
277 | if (prev_entry->activity > 0) | |
278 | prev_entry->activity -= 1; | |
279 | if (entry->activity > prev_entry->activity && | |
280 | entry->activity - prev_entry->activity > | |
281 | CIPSO_V4_CACHE_REORDERLIMIT) { | |
282 | __list_del(entry->list.prev, entry->list.next); | |
283 | __list_add(&entry->list, | |
284 | prev_entry->list.prev, | |
285 | &prev_entry->list); | |
286 | } | |
287 | ||
609c92fe | 288 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
289 | return 0; |
290 | } | |
291 | prev_entry = entry; | |
292 | } | |
609c92fe | 293 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
294 | |
295 | return -ENOENT; | |
296 | } | |
297 | ||
298 | /** | |
299 | * cipso_v4_cache_add - Add an entry to the CIPSO cache | |
300 | * @skb: the packet | |
301 | * @secattr: the packet's security attributes | |
302 | * | |
303 | * Description: | |
304 | * Add a new entry into the CIPSO label mapping cache. Add the new entry to | |
305 | * head of the cache bucket's list, if the cache bucket is out of room remove | |
306 | * the last entry in the list first. It is important to note that there is | |
307 | * currently no checking for duplicate keys. Returns zero on success, | |
308 | * negative values on failure. | |
309 | * | |
310 | */ | |
04f81f01 | 311 | int cipso_v4_cache_add(const unsigned char *cipso_ptr, |
446fda4f PM |
312 | const struct netlbl_lsm_secattr *secattr) |
313 | { | |
314 | int ret_val = -EPERM; | |
315 | u32 bkt; | |
316 | struct cipso_v4_map_cache_entry *entry = NULL; | |
317 | struct cipso_v4_map_cache_entry *old_entry = NULL; | |
446fda4f PM |
318 | u32 cipso_ptr_len; |
319 | ||
320 | if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) | |
321 | return 0; | |
322 | ||
446fda4f PM |
323 | cipso_ptr_len = cipso_ptr[1]; |
324 | ||
325 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); | |
51456b29 | 326 | if (!entry) |
446fda4f | 327 | return -ENOMEM; |
fac5d731 | 328 | entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC); |
51456b29 | 329 | if (!entry->key) { |
446fda4f PM |
330 | ret_val = -ENOMEM; |
331 | goto cache_add_failure; | |
332 | } | |
446fda4f PM |
333 | entry->key_len = cipso_ptr_len; |
334 | entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len); | |
b4217b82 | 335 | refcount_inc(&secattr->cache->refcount); |
ffb733c6 | 336 | entry->lsm_data = secattr->cache; |
446fda4f | 337 | |
5e0f8923 | 338 | bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 339 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
340 | if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { |
341 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
342 | cipso_v4_cache[bkt].size += 1; | |
343 | } else { | |
344 | old_entry = list_entry(cipso_v4_cache[bkt].list.prev, | |
345 | struct cipso_v4_map_cache_entry, list); | |
346 | list_del(&old_entry->list); | |
347 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
348 | cipso_v4_cache_entry_free(old_entry); | |
349 | } | |
609c92fe | 350 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
351 | |
352 | return 0; | |
353 | ||
354 | cache_add_failure: | |
355 | if (entry) | |
356 | cipso_v4_cache_entry_free(entry); | |
357 | return ret_val; | |
358 | } | |
359 | ||
360 | /* | |
361 | * DOI List Functions | |
362 | */ | |
363 | ||
364 | /** | |
365 | * cipso_v4_doi_search - Searches for a DOI definition | |
366 | * @doi: the DOI to search for | |
367 | * | |
368 | * Description: | |
369 | * Search the DOI definition list for a DOI definition with a DOI value that | |
25985edc | 370 | * matches @doi. The caller is responsible for calling rcu_read_[un]lock(). |
446fda4f PM |
371 | * Returns a pointer to the DOI definition on success and NULL on failure. |
372 | */ | |
373 | static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) | |
374 | { | |
375 | struct cipso_v4_doi *iter; | |
376 | ||
377 | list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) | |
f6a6fede | 378 | if (iter->doi == doi && refcount_read(&iter->refcount)) |
446fda4f PM |
379 | return iter; |
380 | return NULL; | |
381 | } | |
382 | ||
383 | /** | |
384 | * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine | |
385 | * @doi_def: the DOI structure | |
6c2e8ac0 | 386 | * @audit_info: NetLabel audit information |
446fda4f PM |
387 | * |
388 | * Description: | |
389 | * The caller defines a new DOI for use by the CIPSO engine and calls this | |
390 | * function to add it to the list of acceptable domains. The caller must | |
391 | * ensure that the mapping table specified in @doi_def->map meets all of the | |
392 | * requirements of the mapping type (see cipso_ipv4.h for details). Returns | |
393 | * zero on success and non-zero on failure. | |
394 | * | |
395 | */ | |
6c2e8ac0 PM |
396 | int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, |
397 | struct netlbl_audit *audit_info) | |
446fda4f | 398 | { |
6c2e8ac0 | 399 | int ret_val = -EINVAL; |
6ce61a7c | 400 | u32 iter; |
6c2e8ac0 PM |
401 | u32 doi; |
402 | u32 doi_type; | |
403 | struct audit_buffer *audit_buf; | |
404 | ||
405 | doi = doi_def->doi; | |
406 | doi_type = doi_def->type; | |
6ce61a7c | 407 | |
56755924 | 408 | if (doi_def->doi == CIPSO_V4_DOI_UNKNOWN) |
6c2e8ac0 | 409 | goto doi_add_return; |
6ce61a7c PM |
410 | for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) { |
411 | switch (doi_def->tags[iter]) { | |
412 | case CIPSO_V4_TAG_RBITMAP: | |
413 | break; | |
484b3669 | 414 | case CIPSO_V4_TAG_RANGE: |
654bbc2a PM |
415 | case CIPSO_V4_TAG_ENUM: |
416 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
6c2e8ac0 | 417 | goto doi_add_return; |
654bbc2a | 418 | break; |
15c45f7b PM |
419 | case CIPSO_V4_TAG_LOCAL: |
420 | if (doi_def->type != CIPSO_V4_MAP_LOCAL) | |
6c2e8ac0 PM |
421 | goto doi_add_return; |
422 | break; | |
423 | case CIPSO_V4_TAG_INVALID: | |
424 | if (iter == 0) | |
425 | goto doi_add_return; | |
15c45f7b | 426 | break; |
6ce61a7c | 427 | default: |
6c2e8ac0 | 428 | goto doi_add_return; |
6ce61a7c PM |
429 | } |
430 | } | |
446fda4f | 431 | |
f6a6fede | 432 | refcount_set(&doi_def->refcount, 1); |
446fda4f | 433 | |
446fda4f | 434 | spin_lock(&cipso_v4_doi_list_lock); |
00db4124 | 435 | if (cipso_v4_doi_search(doi_def->doi)) { |
6c2e8ac0 PM |
436 | spin_unlock(&cipso_v4_doi_list_lock); |
437 | ret_val = -EEXIST; | |
438 | goto doi_add_return; | |
439 | } | |
446fda4f PM |
440 | list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list); |
441 | spin_unlock(&cipso_v4_doi_list_lock); | |
6c2e8ac0 PM |
442 | ret_val = 0; |
443 | ||
444 | doi_add_return: | |
445 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info); | |
00db4124 | 446 | if (audit_buf) { |
6c2e8ac0 PM |
447 | const char *type_str; |
448 | switch (doi_type) { | |
449 | case CIPSO_V4_MAP_TRANS: | |
450 | type_str = "trans"; | |
451 | break; | |
452 | case CIPSO_V4_MAP_PASS: | |
453 | type_str = "pass"; | |
454 | break; | |
455 | case CIPSO_V4_MAP_LOCAL: | |
456 | type_str = "local"; | |
457 | break; | |
458 | default: | |
459 | type_str = "(unknown)"; | |
460 | } | |
461 | audit_log_format(audit_buf, | |
462 | " cipso_doi=%u cipso_type=%s res=%u", | |
463 | doi, type_str, ret_val == 0 ? 1 : 0); | |
464 | audit_log_end(audit_buf); | |
465 | } | |
446fda4f | 466 | |
6c2e8ac0 | 467 | return ret_val; |
446fda4f PM |
468 | } |
469 | ||
b1edeb10 PM |
470 | /** |
471 | * cipso_v4_doi_free - Frees a DOI definition | |
4973404f | 472 | * @doi_def: the DOI definition |
b1edeb10 PM |
473 | * |
474 | * Description: | |
475 | * This function frees all of the memory associated with a DOI definition. | |
476 | * | |
477 | */ | |
478 | void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) | |
479 | { | |
51456b29 | 480 | if (!doi_def) |
b1edeb10 PM |
481 | return; |
482 | ||
483 | switch (doi_def->type) { | |
15c45f7b | 484 | case CIPSO_V4_MAP_TRANS: |
b1edeb10 PM |
485 | kfree(doi_def->map.std->lvl.cipso); |
486 | kfree(doi_def->map.std->lvl.local); | |
487 | kfree(doi_def->map.std->cat.cipso); | |
488 | kfree(doi_def->map.std->cat.local); | |
489 | break; | |
490 | } | |
491 | kfree(doi_def); | |
492 | } | |
493 | ||
494 | /** | |
495 | * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer | |
496 | * @entry: the entry's RCU field | |
497 | * | |
498 | * Description: | |
499 | * This function is designed to be used as a callback to the call_rcu() | |
500 | * function so that the memory allocated to the DOI definition can be released | |
501 | * safely. | |
502 | * | |
503 | */ | |
504 | static void cipso_v4_doi_free_rcu(struct rcu_head *entry) | |
505 | { | |
506 | struct cipso_v4_doi *doi_def; | |
507 | ||
508 | doi_def = container_of(entry, struct cipso_v4_doi, rcu); | |
509 | cipso_v4_doi_free(doi_def); | |
510 | } | |
511 | ||
446fda4f PM |
512 | /** |
513 | * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine | |
514 | * @doi: the DOI value | |
32f50cde | 515 | * @audit_secid: the LSM secid to use in the audit message |
446fda4f PM |
516 | * |
517 | * Description: | |
b1edeb10 PM |
518 | * Removes a DOI definition from the CIPSO engine. The NetLabel routines will |
519 | * be called to release their own LSM domain mappings as well as our own | |
520 | * domain list. Returns zero on success and negative values on failure. | |
446fda4f PM |
521 | * |
522 | */ | |
b1edeb10 | 523 | int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info) |
446fda4f | 524 | { |
6c2e8ac0 | 525 | int ret_val; |
446fda4f | 526 | struct cipso_v4_doi *doi_def; |
6c2e8ac0 | 527 | struct audit_buffer *audit_buf; |
446fda4f | 528 | |
4be2700f PM |
529 | spin_lock(&cipso_v4_doi_list_lock); |
530 | doi_def = cipso_v4_doi_search(doi); | |
51456b29 | 531 | if (!doi_def) { |
446fda4f | 532 | spin_unlock(&cipso_v4_doi_list_lock); |
6c2e8ac0 PM |
533 | ret_val = -ENOENT; |
534 | goto doi_remove_return; | |
446fda4f | 535 | } |
f6a6fede | 536 | if (!refcount_dec_and_test(&doi_def->refcount)) { |
b1edeb10 | 537 | spin_unlock(&cipso_v4_doi_list_lock); |
6c2e8ac0 PM |
538 | ret_val = -EBUSY; |
539 | goto doi_remove_return; | |
b1edeb10 PM |
540 | } |
541 | list_del_rcu(&doi_def->list); | |
4be2700f | 542 | spin_unlock(&cipso_v4_doi_list_lock); |
446fda4f | 543 | |
b1edeb10 PM |
544 | cipso_v4_cache_invalidate(); |
545 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
6c2e8ac0 PM |
546 | ret_val = 0; |
547 | ||
548 | doi_remove_return: | |
549 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info); | |
00db4124 | 550 | if (audit_buf) { |
6c2e8ac0 PM |
551 | audit_log_format(audit_buf, |
552 | " cipso_doi=%u res=%u", | |
553 | doi, ret_val == 0 ? 1 : 0); | |
554 | audit_log_end(audit_buf); | |
555 | } | |
b1edeb10 | 556 | |
6c2e8ac0 | 557 | return ret_val; |
446fda4f PM |
558 | } |
559 | ||
560 | /** | |
b1edeb10 | 561 | * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition |
446fda4f PM |
562 | * @doi: the DOI value |
563 | * | |
564 | * Description: | |
565 | * Searches for a valid DOI definition and if one is found it is returned to | |
566 | * the caller. Otherwise NULL is returned. The caller must ensure that | |
b1edeb10 PM |
567 | * rcu_read_lock() is held while accessing the returned definition and the DOI |
568 | * definition reference count is decremented when the caller is done. | |
446fda4f PM |
569 | * |
570 | */ | |
571 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) | |
572 | { | |
b1edeb10 PM |
573 | struct cipso_v4_doi *doi_def; |
574 | ||
575 | rcu_read_lock(); | |
576 | doi_def = cipso_v4_doi_search(doi); | |
51456b29 | 577 | if (!doi_def) |
b1edeb10 | 578 | goto doi_getdef_return; |
f6a6fede | 579 | if (!refcount_inc_not_zero(&doi_def->refcount)) |
b1edeb10 PM |
580 | doi_def = NULL; |
581 | ||
582 | doi_getdef_return: | |
583 | rcu_read_unlock(); | |
584 | return doi_def; | |
585 | } | |
586 | ||
587 | /** | |
588 | * cipso_v4_doi_putdef - Releases a reference for the given DOI definition | |
589 | * @doi_def: the DOI definition | |
590 | * | |
591 | * Description: | |
592 | * Releases a DOI definition reference obtained from cipso_v4_doi_getdef(). | |
593 | * | |
594 | */ | |
595 | void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) | |
596 | { | |
51456b29 | 597 | if (!doi_def) |
b1edeb10 PM |
598 | return; |
599 | ||
f6a6fede | 600 | if (!refcount_dec_and_test(&doi_def->refcount)) |
b1edeb10 PM |
601 | return; |
602 | spin_lock(&cipso_v4_doi_list_lock); | |
603 | list_del_rcu(&doi_def->list); | |
604 | spin_unlock(&cipso_v4_doi_list_lock); | |
605 | ||
606 | cipso_v4_cache_invalidate(); | |
607 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
446fda4f PM |
608 | } |
609 | ||
610 | /** | |
fcd48280 PM |
611 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
612 | * @skip_cnt: skip past this number of DOI definitions, updated | |
613 | * @callback: callback for each DOI definition | |
614 | * @cb_arg: argument for the callback function | |
446fda4f PM |
615 | * |
616 | * Description: | |
fcd48280 PM |
617 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
618 | * For each entry call @callback, if @callback returns a negative value stop | |
619 | * 'walking' through the list and return. Updates the value in @skip_cnt upon | |
620 | * return. Returns zero on success, negative values on failure. | |
446fda4f PM |
621 | * |
622 | */ | |
fcd48280 PM |
623 | int cipso_v4_doi_walk(u32 *skip_cnt, |
624 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), | |
625 | void *cb_arg) | |
446fda4f | 626 | { |
fcd48280 | 627 | int ret_val = -ENOENT; |
446fda4f | 628 | u32 doi_cnt = 0; |
fcd48280 | 629 | struct cipso_v4_doi *iter_doi; |
446fda4f | 630 | |
446fda4f | 631 | rcu_read_lock(); |
fcd48280 | 632 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
f6a6fede | 633 | if (refcount_read(&iter_doi->refcount) > 0) { |
fcd48280 PM |
634 | if (doi_cnt++ < *skip_cnt) |
635 | continue; | |
636 | ret_val = callback(iter_doi, cb_arg); | |
637 | if (ret_val < 0) { | |
638 | doi_cnt--; | |
639 | goto doi_walk_return; | |
446fda4f | 640 | } |
446fda4f | 641 | } |
446fda4f | 642 | |
fcd48280 | 643 | doi_walk_return: |
446fda4f | 644 | rcu_read_unlock(); |
fcd48280 PM |
645 | *skip_cnt = doi_cnt; |
646 | return ret_val; | |
446fda4f PM |
647 | } |
648 | ||
446fda4f PM |
649 | /* |
650 | * Label Mapping Functions | |
651 | */ | |
652 | ||
653 | /** | |
654 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood | |
655 | * @doi_def: the DOI definition | |
656 | * @level: the level to check | |
657 | * | |
658 | * Description: | |
659 | * Checks the given level against the given DOI definition and returns a | |
660 | * negative value if the level does not have a valid mapping and a zero value | |
661 | * if the level is defined by the DOI. | |
662 | * | |
663 | */ | |
664 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) | |
665 | { | |
666 | switch (doi_def->type) { | |
667 | case CIPSO_V4_MAP_PASS: | |
668 | return 0; | |
15c45f7b | 669 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
670 | if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL) |
671 | return 0; | |
672 | break; | |
673 | } | |
674 | ||
675 | return -EFAULT; | |
676 | } | |
677 | ||
678 | /** | |
679 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network | |
680 | * @doi_def: the DOI definition | |
681 | * @host_lvl: the host MLS level | |
682 | * @net_lvl: the network/CIPSO MLS level | |
683 | * | |
684 | * Description: | |
685 | * Perform a label mapping to translate a local MLS level to the correct | |
686 | * CIPSO level using the given DOI definition. Returns zero on success, | |
687 | * negative values otherwise. | |
688 | * | |
689 | */ | |
690 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, | |
691 | u32 host_lvl, | |
692 | u32 *net_lvl) | |
693 | { | |
694 | switch (doi_def->type) { | |
695 | case CIPSO_V4_MAP_PASS: | |
696 | *net_lvl = host_lvl; | |
697 | return 0; | |
15c45f7b | 698 | case CIPSO_V4_MAP_TRANS: |
c6387a86 PM |
699 | if (host_lvl < doi_def->map.std->lvl.local_size && |
700 | doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) { | |
446fda4f PM |
701 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
702 | return 0; | |
703 | } | |
c6387a86 | 704 | return -EPERM; |
446fda4f PM |
705 | } |
706 | ||
707 | return -EINVAL; | |
708 | } | |
709 | ||
710 | /** | |
711 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host | |
712 | * @doi_def: the DOI definition | |
713 | * @net_lvl: the network/CIPSO MLS level | |
714 | * @host_lvl: the host MLS level | |
715 | * | |
716 | * Description: | |
717 | * Perform a label mapping to translate a CIPSO level to the correct local MLS | |
718 | * level using the given DOI definition. Returns zero on success, negative | |
719 | * values otherwise. | |
720 | * | |
721 | */ | |
722 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, | |
723 | u32 net_lvl, | |
724 | u32 *host_lvl) | |
725 | { | |
726 | struct cipso_v4_std_map_tbl *map_tbl; | |
727 | ||
728 | switch (doi_def->type) { | |
729 | case CIPSO_V4_MAP_PASS: | |
730 | *host_lvl = net_lvl; | |
731 | return 0; | |
15c45f7b | 732 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
733 | map_tbl = doi_def->map.std; |
734 | if (net_lvl < map_tbl->lvl.cipso_size && | |
735 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { | |
736 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; | |
737 | return 0; | |
738 | } | |
c6387a86 | 739 | return -EPERM; |
446fda4f PM |
740 | } |
741 | ||
742 | return -EINVAL; | |
743 | } | |
744 | ||
745 | /** | |
746 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid | |
747 | * @doi_def: the DOI definition | |
748 | * @bitmap: category bitmap | |
749 | * @bitmap_len: bitmap length in bytes | |
750 | * | |
751 | * Description: | |
752 | * Checks the given category bitmap against the given DOI definition and | |
753 | * returns a negative value if any of the categories in the bitmap do not have | |
754 | * a valid mapping and a zero value if all of the categories are valid. | |
755 | * | |
756 | */ | |
757 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, | |
758 | const unsigned char *bitmap, | |
759 | u32 bitmap_len) | |
760 | { | |
761 | int cat = -1; | |
762 | u32 bitmap_len_bits = bitmap_len * 8; | |
044a68ed PM |
763 | u32 cipso_cat_size; |
764 | u32 *cipso_array; | |
446fda4f PM |
765 | |
766 | switch (doi_def->type) { | |
767 | case CIPSO_V4_MAP_PASS: | |
768 | return 0; | |
15c45f7b | 769 | case CIPSO_V4_MAP_TRANS: |
044a68ed PM |
770 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
771 | cipso_array = doi_def->map.std->cat.cipso; | |
446fda4f | 772 | for (;;) { |
3faa8f98 HD |
773 | cat = netlbl_bitmap_walk(bitmap, |
774 | bitmap_len_bits, | |
775 | cat + 1, | |
776 | 1); | |
446fda4f PM |
777 | if (cat < 0) |
778 | break; | |
779 | if (cat >= cipso_cat_size || | |
780 | cipso_array[cat] >= CIPSO_V4_INV_CAT) | |
781 | return -EFAULT; | |
782 | } | |
783 | ||
784 | if (cat == -1) | |
785 | return 0; | |
786 | break; | |
787 | } | |
788 | ||
789 | return -EFAULT; | |
790 | } | |
791 | ||
792 | /** | |
793 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network | |
794 | * @doi_def: the DOI definition | |
02752760 | 795 | * @secattr: the security attributes |
446fda4f PM |
796 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
797 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
798 | * | |
799 | * Description: | |
800 | * Perform a label mapping to translate a local MLS category bitmap to the | |
801 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum | |
802 | * size in bytes of the network bitmap on success, negative values otherwise. | |
803 | * | |
804 | */ | |
805 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, | |
02752760 | 806 | const struct netlbl_lsm_secattr *secattr, |
446fda4f PM |
807 | unsigned char *net_cat, |
808 | u32 net_cat_len) | |
809 | { | |
810 | int host_spot = -1; | |
02752760 | 811 | u32 net_spot = CIPSO_V4_INV_CAT; |
446fda4f | 812 | u32 net_spot_max = 0; |
446fda4f | 813 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
814 | u32 host_cat_size = 0; |
815 | u32 *host_cat_array = NULL; | |
446fda4f | 816 | |
15c45f7b | 817 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
818 | host_cat_size = doi_def->map.std->cat.local_size; |
819 | host_cat_array = doi_def->map.std->cat.local; | |
02752760 PM |
820 | } |
821 | ||
822 | for (;;) { | |
4fbe63d1 PM |
823 | host_spot = netlbl_catmap_walk(secattr->attr.mls.cat, |
824 | host_spot + 1); | |
02752760 PM |
825 | if (host_spot < 0) |
826 | break; | |
827 | ||
828 | switch (doi_def->type) { | |
829 | case CIPSO_V4_MAP_PASS: | |
830 | net_spot = host_spot; | |
831 | break; | |
15c45f7b | 832 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
833 | if (host_spot >= host_cat_size) |
834 | return -EPERM; | |
446fda4f | 835 | net_spot = host_cat_array[host_spot]; |
9fade4bf PM |
836 | if (net_spot >= CIPSO_V4_INV_CAT) |
837 | return -EPERM; | |
02752760 | 838 | break; |
446fda4f | 839 | } |
02752760 PM |
840 | if (net_spot >= net_clen_bits) |
841 | return -ENOSPC; | |
3faa8f98 | 842 | netlbl_bitmap_setbit(net_cat, net_spot, 1); |
446fda4f | 843 | |
02752760 PM |
844 | if (net_spot > net_spot_max) |
845 | net_spot_max = net_spot; | |
446fda4f PM |
846 | } |
847 | ||
02752760 PM |
848 | if (++net_spot_max % 8) |
849 | return net_spot_max / 8 + 1; | |
850 | return net_spot_max / 8; | |
446fda4f PM |
851 | } |
852 | ||
853 | /** | |
854 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host | |
855 | * @doi_def: the DOI definition | |
856 | * @net_cat: the category bitmap in network/CIPSO format | |
857 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
02752760 | 858 | * @secattr: the security attributes |
446fda4f PM |
859 | * |
860 | * Description: | |
861 | * Perform a label mapping to translate a CIPSO bitmap to the correct local | |
02752760 PM |
862 | * MLS category bitmap using the given DOI definition. Returns zero on |
863 | * success, negative values on failure. | |
446fda4f PM |
864 | * |
865 | */ | |
866 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, | |
867 | const unsigned char *net_cat, | |
868 | u32 net_cat_len, | |
02752760 | 869 | struct netlbl_lsm_secattr *secattr) |
446fda4f | 870 | { |
02752760 | 871 | int ret_val; |
446fda4f | 872 | int net_spot = -1; |
02752760 | 873 | u32 host_spot = CIPSO_V4_INV_CAT; |
446fda4f | 874 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
875 | u32 net_cat_size = 0; |
876 | u32 *net_cat_array = NULL; | |
446fda4f | 877 | |
15c45f7b | 878 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
879 | net_cat_size = doi_def->map.std->cat.cipso_size; |
880 | net_cat_array = doi_def->map.std->cat.cipso; | |
02752760 | 881 | } |
446fda4f | 882 | |
02752760 | 883 | for (;;) { |
3faa8f98 HD |
884 | net_spot = netlbl_bitmap_walk(net_cat, |
885 | net_clen_bits, | |
886 | net_spot + 1, | |
887 | 1); | |
02752760 PM |
888 | if (net_spot < 0) { |
889 | if (net_spot == -2) | |
890 | return -EFAULT; | |
891 | return 0; | |
892 | } | |
893 | ||
894 | switch (doi_def->type) { | |
895 | case CIPSO_V4_MAP_PASS: | |
896 | host_spot = net_spot; | |
897 | break; | |
15c45f7b | 898 | case CIPSO_V4_MAP_TRANS: |
02752760 PM |
899 | if (net_spot >= net_cat_size) |
900 | return -EPERM; | |
446fda4f | 901 | host_spot = net_cat_array[net_spot]; |
9fade4bf PM |
902 | if (host_spot >= CIPSO_V4_INV_CAT) |
903 | return -EPERM; | |
02752760 | 904 | break; |
446fda4f | 905 | } |
4fbe63d1 | 906 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
02752760 PM |
907 | host_spot, |
908 | GFP_ATOMIC); | |
909 | if (ret_val != 0) | |
910 | return ret_val; | |
446fda4f PM |
911 | } |
912 | ||
913 | return -EINVAL; | |
914 | } | |
915 | ||
654bbc2a PM |
916 | /** |
917 | * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid | |
918 | * @doi_def: the DOI definition | |
919 | * @enumcat: category list | |
920 | * @enumcat_len: length of the category list in bytes | |
921 | * | |
922 | * Description: | |
923 | * Checks the given categories against the given DOI definition and returns a | |
924 | * negative value if any of the categories do not have a valid mapping and a | |
925 | * zero value if all of the categories are valid. | |
926 | * | |
927 | */ | |
928 | static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, | |
929 | const unsigned char *enumcat, | |
930 | u32 enumcat_len) | |
931 | { | |
932 | u16 cat; | |
933 | int cat_prev = -1; | |
934 | u32 iter; | |
935 | ||
936 | if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01) | |
937 | return -EFAULT; | |
938 | ||
939 | for (iter = 0; iter < enumcat_len; iter += 2) { | |
d3e2ce3b | 940 | cat = get_unaligned_be16(&enumcat[iter]); |
654bbc2a PM |
941 | if (cat <= cat_prev) |
942 | return -EFAULT; | |
943 | cat_prev = cat; | |
944 | } | |
945 | ||
946 | return 0; | |
947 | } | |
948 | ||
949 | /** | |
950 | * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network | |
951 | * @doi_def: the DOI definition | |
952 | * @secattr: the security attributes | |
953 | * @net_cat: the zero'd out category list in network/CIPSO format | |
954 | * @net_cat_len: the length of the CIPSO category list in bytes | |
955 | * | |
956 | * Description: | |
957 | * Perform a label mapping to translate a local MLS category bitmap to the | |
958 | * correct CIPSO category list using the given DOI definition. Returns the | |
959 | * size in bytes of the network category bitmap on success, negative values | |
960 | * otherwise. | |
961 | * | |
962 | */ | |
963 | static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, | |
964 | const struct netlbl_lsm_secattr *secattr, | |
965 | unsigned char *net_cat, | |
966 | u32 net_cat_len) | |
967 | { | |
968 | int cat = -1; | |
969 | u32 cat_iter = 0; | |
970 | ||
971 | for (;;) { | |
4fbe63d1 | 972 | cat = netlbl_catmap_walk(secattr->attr.mls.cat, cat + 1); |
654bbc2a PM |
973 | if (cat < 0) |
974 | break; | |
975 | if ((cat_iter + 2) > net_cat_len) | |
976 | return -ENOSPC; | |
977 | ||
978 | *((__be16 *)&net_cat[cat_iter]) = htons(cat); | |
979 | cat_iter += 2; | |
980 | } | |
981 | ||
982 | return cat_iter; | |
983 | } | |
984 | ||
985 | /** | |
986 | * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host | |
987 | * @doi_def: the DOI definition | |
988 | * @net_cat: the category list in network/CIPSO format | |
989 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
990 | * @secattr: the security attributes | |
991 | * | |
992 | * Description: | |
993 | * Perform a label mapping to translate a CIPSO category list to the correct | |
994 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
995 | * success, negative values on failure. | |
996 | * | |
997 | */ | |
998 | static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, | |
999 | const unsigned char *net_cat, | |
1000 | u32 net_cat_len, | |
1001 | struct netlbl_lsm_secattr *secattr) | |
1002 | { | |
1003 | int ret_val; | |
1004 | u32 iter; | |
1005 | ||
1006 | for (iter = 0; iter < net_cat_len; iter += 2) { | |
4fbe63d1 PM |
1007 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
1008 | get_unaligned_be16(&net_cat[iter]), | |
1009 | GFP_ATOMIC); | |
654bbc2a PM |
1010 | if (ret_val != 0) |
1011 | return ret_val; | |
1012 | } | |
1013 | ||
1014 | return 0; | |
1015 | } | |
1016 | ||
484b3669 PM |
1017 | /** |
1018 | * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid | |
1019 | * @doi_def: the DOI definition | |
1020 | * @rngcat: category list | |
1021 | * @rngcat_len: length of the category list in bytes | |
1022 | * | |
1023 | * Description: | |
1024 | * Checks the given categories against the given DOI definition and returns a | |
1025 | * negative value if any of the categories do not have a valid mapping and a | |
1026 | * zero value if all of the categories are valid. | |
1027 | * | |
1028 | */ | |
1029 | static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, | |
1030 | const unsigned char *rngcat, | |
1031 | u32 rngcat_len) | |
1032 | { | |
1033 | u16 cat_high; | |
1034 | u16 cat_low; | |
1035 | u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1; | |
1036 | u32 iter; | |
1037 | ||
1038 | if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01) | |
1039 | return -EFAULT; | |
1040 | ||
1041 | for (iter = 0; iter < rngcat_len; iter += 4) { | |
d3e2ce3b | 1042 | cat_high = get_unaligned_be16(&rngcat[iter]); |
484b3669 | 1043 | if ((iter + 4) <= rngcat_len) |
d3e2ce3b | 1044 | cat_low = get_unaligned_be16(&rngcat[iter + 2]); |
484b3669 PM |
1045 | else |
1046 | cat_low = 0; | |
1047 | ||
1048 | if (cat_high > cat_prev) | |
1049 | return -EFAULT; | |
1050 | ||
1051 | cat_prev = cat_low; | |
1052 | } | |
1053 | ||
1054 | return 0; | |
1055 | } | |
1056 | ||
1057 | /** | |
1058 | * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network | |
1059 | * @doi_def: the DOI definition | |
1060 | * @secattr: the security attributes | |
1061 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1062 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1063 | * | |
1064 | * Description: | |
1065 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1066 | * correct CIPSO category list using the given DOI definition. Returns the | |
1067 | * size in bytes of the network category bitmap on success, negative values | |
1068 | * otherwise. | |
1069 | * | |
1070 | */ | |
1071 | static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, | |
1072 | const struct netlbl_lsm_secattr *secattr, | |
1073 | unsigned char *net_cat, | |
1074 | u32 net_cat_len) | |
1075 | { | |
484b3669 | 1076 | int iter = -1; |
f998e8cb | 1077 | u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2]; |
484b3669 PM |
1078 | u32 array_cnt = 0; |
1079 | u32 cat_size = 0; | |
1080 | ||
f998e8cb | 1081 | /* make sure we don't overflow the 'array[]' variable */ |
128c6b6c PM |
1082 | if (net_cat_len > |
1083 | (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN)) | |
1084 | return -ENOSPC; | |
484b3669 PM |
1085 | |
1086 | for (;;) { | |
4fbe63d1 | 1087 | iter = netlbl_catmap_walk(secattr->attr.mls.cat, iter + 1); |
484b3669 PM |
1088 | if (iter < 0) |
1089 | break; | |
1090 | cat_size += (iter == 0 ? 0 : sizeof(u16)); | |
1091 | if (cat_size > net_cat_len) | |
1092 | return -ENOSPC; | |
1093 | array[array_cnt++] = iter; | |
1094 | ||
4fbe63d1 | 1095 | iter = netlbl_catmap_walkrng(secattr->attr.mls.cat, iter); |
484b3669 PM |
1096 | if (iter < 0) |
1097 | return -EFAULT; | |
1098 | cat_size += sizeof(u16); | |
1099 | if (cat_size > net_cat_len) | |
1100 | return -ENOSPC; | |
1101 | array[array_cnt++] = iter; | |
1102 | } | |
1103 | ||
1104 | for (iter = 0; array_cnt > 0;) { | |
1105 | *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]); | |
1106 | iter += 2; | |
1107 | array_cnt--; | |
1108 | if (array[array_cnt] != 0) { | |
1109 | *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]); | |
1110 | iter += 2; | |
1111 | } | |
1112 | } | |
1113 | ||
1114 | return cat_size; | |
1115 | } | |
1116 | ||
1117 | /** | |
1118 | * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host | |
1119 | * @doi_def: the DOI definition | |
1120 | * @net_cat: the category list in network/CIPSO format | |
1121 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1122 | * @secattr: the security attributes | |
1123 | * | |
1124 | * Description: | |
1125 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1126 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1127 | * success, negative values on failure. | |
1128 | * | |
1129 | */ | |
1130 | static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, | |
1131 | const unsigned char *net_cat, | |
1132 | u32 net_cat_len, | |
1133 | struct netlbl_lsm_secattr *secattr) | |
1134 | { | |
1135 | int ret_val; | |
1136 | u32 net_iter; | |
1137 | u16 cat_low; | |
1138 | u16 cat_high; | |
1139 | ||
132adf54 | 1140 | for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) { |
d3e2ce3b | 1141 | cat_high = get_unaligned_be16(&net_cat[net_iter]); |
484b3669 | 1142 | if ((net_iter + 4) <= net_cat_len) |
d3e2ce3b | 1143 | cat_low = get_unaligned_be16(&net_cat[net_iter + 2]); |
484b3669 PM |
1144 | else |
1145 | cat_low = 0; | |
1146 | ||
4fbe63d1 PM |
1147 | ret_val = netlbl_catmap_setrng(&secattr->attr.mls.cat, |
1148 | cat_low, | |
1149 | cat_high, | |
1150 | GFP_ATOMIC); | |
484b3669 PM |
1151 | if (ret_val != 0) |
1152 | return ret_val; | |
1153 | } | |
1154 | ||
1155 | return 0; | |
1156 | } | |
1157 | ||
446fda4f PM |
1158 | /* |
1159 | * Protocol Handling Functions | |
1160 | */ | |
1161 | ||
446fda4f PM |
1162 | /** |
1163 | * cipso_v4_gentag_hdr - Generate a CIPSO option header | |
1164 | * @doi_def: the DOI definition | |
91b1ed0a | 1165 | * @len: the total tag length in bytes, not including this header |
446fda4f PM |
1166 | * @buf: the CIPSO option buffer |
1167 | * | |
1168 | * Description: | |
91b1ed0a | 1169 | * Write a CIPSO header into the beginning of @buffer. |
446fda4f PM |
1170 | * |
1171 | */ | |
91b1ed0a PM |
1172 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
1173 | unsigned char *buf, | |
1174 | u32 len) | |
446fda4f | 1175 | { |
446fda4f PM |
1176 | buf[0] = IPOPT_CIPSO; |
1177 | buf[1] = CIPSO_V4_HDR_LEN + len; | |
714e85be | 1178 | *(__be32 *)&buf[2] = htonl(doi_def->doi); |
446fda4f PM |
1179 | } |
1180 | ||
446fda4f PM |
1181 | /** |
1182 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) | |
1183 | * @doi_def: the DOI definition | |
1184 | * @secattr: the security attributes | |
1185 | * @buffer: the option buffer | |
1186 | * @buffer_len: length of buffer in bytes | |
1187 | * | |
1188 | * Description: | |
1189 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The | |
1190 | * actual buffer length may be larger than the indicated size due to | |
91b1ed0a PM |
1191 | * translation between host and network category bitmaps. Returns the size of |
1192 | * the tag on success, negative values on failure. | |
446fda4f PM |
1193 | * |
1194 | */ | |
1195 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, | |
1196 | const struct netlbl_lsm_secattr *secattr, | |
91b1ed0a PM |
1197 | unsigned char *buffer, |
1198 | u32 buffer_len) | |
446fda4f | 1199 | { |
701a90ba | 1200 | int ret_val; |
91b1ed0a | 1201 | u32 tag_len; |
446fda4f PM |
1202 | u32 level; |
1203 | ||
701a90ba PM |
1204 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
1205 | return -EPERM; | |
1206 | ||
16efd454 PM |
1207 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1208 | secattr->attr.mls.lvl, | |
1209 | &level); | |
91b1ed0a PM |
1210 | if (ret_val != 0) |
1211 | return ret_val; | |
446fda4f | 1212 | |
91b1ed0a | 1213 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
446fda4f | 1214 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
02752760 | 1215 | secattr, |
91b1ed0a PM |
1216 | &buffer[4], |
1217 | buffer_len - 4); | |
446fda4f | 1218 | if (ret_val < 0) |
91b1ed0a | 1219 | return ret_val; |
446fda4f PM |
1220 | |
1221 | /* This will send packets using the "optimized" format when | |
25985edc | 1222 | * possible as specified in section 3.4.2.6 of the |
446fda4f | 1223 | * CIPSO draft. */ |
701a90ba | 1224 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
91b1ed0a | 1225 | tag_len = 14; |
701a90ba | 1226 | else |
91b1ed0a PM |
1227 | tag_len = 4 + ret_val; |
1228 | } else | |
1229 | tag_len = 4; | |
446fda4f | 1230 | |
15c45f7b | 1231 | buffer[0] = CIPSO_V4_TAG_RBITMAP; |
91b1ed0a PM |
1232 | buffer[1] = tag_len; |
1233 | buffer[3] = level; | |
446fda4f | 1234 | |
91b1ed0a | 1235 | return tag_len; |
446fda4f PM |
1236 | } |
1237 | ||
1238 | /** | |
1239 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag | |
1240 | * @doi_def: the DOI definition | |
1241 | * @tag: the CIPSO tag | |
1242 | * @secattr: the security attributes | |
1243 | * | |
1244 | * Description: | |
1245 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security | |
1246 | * attributes in @secattr. Return zero on success, negatives values on | |
1247 | * failure. | |
1248 | * | |
1249 | */ | |
1250 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, | |
1251 | const unsigned char *tag, | |
1252 | struct netlbl_lsm_secattr *secattr) | |
1253 | { | |
1254 | int ret_val; | |
1255 | u8 tag_len = tag[1]; | |
1256 | u32 level; | |
1257 | ||
1258 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1259 | if (ret_val != 0) | |
1260 | return ret_val; | |
16efd454 | 1261 | secattr->attr.mls.lvl = level; |
701a90ba | 1262 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
446fda4f PM |
1263 | |
1264 | if (tag_len > 4) { | |
446fda4f PM |
1265 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, |
1266 | &tag[4], | |
1267 | tag_len - 4, | |
02752760 PM |
1268 | secattr); |
1269 | if (ret_val != 0) { | |
4fbe63d1 | 1270 | netlbl_catmap_free(secattr->attr.mls.cat); |
446fda4f PM |
1271 | return ret_val; |
1272 | } | |
02752760 PM |
1273 | |
1274 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
446fda4f PM |
1275 | } |
1276 | ||
1277 | return 0; | |
1278 | } | |
1279 | ||
654bbc2a PM |
1280 | /** |
1281 | * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) | |
1282 | * @doi_def: the DOI definition | |
1283 | * @secattr: the security attributes | |
1284 | * @buffer: the option buffer | |
1285 | * @buffer_len: length of buffer in bytes | |
1286 | * | |
1287 | * Description: | |
1288 | * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the | |
1289 | * size of the tag on success, negative values on failure. | |
1290 | * | |
1291 | */ | |
1292 | static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, | |
1293 | const struct netlbl_lsm_secattr *secattr, | |
1294 | unsigned char *buffer, | |
1295 | u32 buffer_len) | |
1296 | { | |
1297 | int ret_val; | |
1298 | u32 tag_len; | |
1299 | u32 level; | |
1300 | ||
1301 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1302 | return -EPERM; | |
1303 | ||
16efd454 PM |
1304 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1305 | secattr->attr.mls.lvl, | |
1306 | &level); | |
654bbc2a PM |
1307 | if (ret_val != 0) |
1308 | return ret_val; | |
1309 | ||
1310 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1311 | ret_val = cipso_v4_map_cat_enum_hton(doi_def, | |
1312 | secattr, | |
1313 | &buffer[4], | |
1314 | buffer_len - 4); | |
1315 | if (ret_val < 0) | |
1316 | return ret_val; | |
1317 | ||
1318 | tag_len = 4 + ret_val; | |
1319 | } else | |
1320 | tag_len = 4; | |
1321 | ||
15c45f7b | 1322 | buffer[0] = CIPSO_V4_TAG_ENUM; |
654bbc2a PM |
1323 | buffer[1] = tag_len; |
1324 | buffer[3] = level; | |
1325 | ||
1326 | return tag_len; | |
1327 | } | |
1328 | ||
1329 | /** | |
1330 | * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag | |
1331 | * @doi_def: the DOI definition | |
1332 | * @tag: the CIPSO tag | |
1333 | * @secattr: the security attributes | |
1334 | * | |
1335 | * Description: | |
1336 | * Parse a CIPSO enumerated tag (tag type #2) and return the security | |
1337 | * attributes in @secattr. Return zero on success, negatives values on | |
1338 | * failure. | |
1339 | * | |
1340 | */ | |
1341 | static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, | |
1342 | const unsigned char *tag, | |
1343 | struct netlbl_lsm_secattr *secattr) | |
1344 | { | |
1345 | int ret_val; | |
1346 | u8 tag_len = tag[1]; | |
1347 | u32 level; | |
1348 | ||
1349 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1350 | if (ret_val != 0) | |
1351 | return ret_val; | |
16efd454 | 1352 | secattr->attr.mls.lvl = level; |
654bbc2a PM |
1353 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1354 | ||
1355 | if (tag_len > 4) { | |
654bbc2a PM |
1356 | ret_val = cipso_v4_map_cat_enum_ntoh(doi_def, |
1357 | &tag[4], | |
1358 | tag_len - 4, | |
1359 | secattr); | |
1360 | if (ret_val != 0) { | |
4fbe63d1 | 1361 | netlbl_catmap_free(secattr->attr.mls.cat); |
654bbc2a PM |
1362 | return ret_val; |
1363 | } | |
1364 | ||
1365 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1366 | } | |
1367 | ||
1368 | return 0; | |
1369 | } | |
1370 | ||
484b3669 PM |
1371 | /** |
1372 | * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) | |
1373 | * @doi_def: the DOI definition | |
1374 | * @secattr: the security attributes | |
1375 | * @buffer: the option buffer | |
1376 | * @buffer_len: length of buffer in bytes | |
1377 | * | |
1378 | * Description: | |
1379 | * Generate a CIPSO option using the ranged tag, tag type #5. Returns the | |
1380 | * size of the tag on success, negative values on failure. | |
1381 | * | |
1382 | */ | |
1383 | static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, | |
1384 | const struct netlbl_lsm_secattr *secattr, | |
1385 | unsigned char *buffer, | |
1386 | u32 buffer_len) | |
1387 | { | |
1388 | int ret_val; | |
1389 | u32 tag_len; | |
1390 | u32 level; | |
1391 | ||
1392 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1393 | return -EPERM; | |
1394 | ||
16efd454 PM |
1395 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1396 | secattr->attr.mls.lvl, | |
1397 | &level); | |
484b3669 PM |
1398 | if (ret_val != 0) |
1399 | return ret_val; | |
1400 | ||
1401 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1402 | ret_val = cipso_v4_map_cat_rng_hton(doi_def, | |
1403 | secattr, | |
1404 | &buffer[4], | |
1405 | buffer_len - 4); | |
1406 | if (ret_val < 0) | |
1407 | return ret_val; | |
1408 | ||
1409 | tag_len = 4 + ret_val; | |
1410 | } else | |
1411 | tag_len = 4; | |
1412 | ||
15c45f7b | 1413 | buffer[0] = CIPSO_V4_TAG_RANGE; |
484b3669 PM |
1414 | buffer[1] = tag_len; |
1415 | buffer[3] = level; | |
1416 | ||
1417 | return tag_len; | |
1418 | } | |
1419 | ||
1420 | /** | |
1421 | * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag | |
1422 | * @doi_def: the DOI definition | |
1423 | * @tag: the CIPSO tag | |
1424 | * @secattr: the security attributes | |
1425 | * | |
1426 | * Description: | |
1427 | * Parse a CIPSO ranged tag (tag type #5) and return the security attributes | |
1428 | * in @secattr. Return zero on success, negatives values on failure. | |
1429 | * | |
1430 | */ | |
1431 | static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, | |
1432 | const unsigned char *tag, | |
1433 | struct netlbl_lsm_secattr *secattr) | |
1434 | { | |
1435 | int ret_val; | |
1436 | u8 tag_len = tag[1]; | |
1437 | u32 level; | |
1438 | ||
1439 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1440 | if (ret_val != 0) | |
1441 | return ret_val; | |
16efd454 | 1442 | secattr->attr.mls.lvl = level; |
484b3669 PM |
1443 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1444 | ||
1445 | if (tag_len > 4) { | |
484b3669 PM |
1446 | ret_val = cipso_v4_map_cat_rng_ntoh(doi_def, |
1447 | &tag[4], | |
1448 | tag_len - 4, | |
1449 | secattr); | |
1450 | if (ret_val != 0) { | |
4fbe63d1 | 1451 | netlbl_catmap_free(secattr->attr.mls.cat); |
484b3669 PM |
1452 | return ret_val; |
1453 | } | |
1454 | ||
1455 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1456 | } | |
1457 | ||
1458 | return 0; | |
1459 | } | |
1460 | ||
15c45f7b PM |
1461 | /** |
1462 | * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard) | |
1463 | * @doi_def: the DOI definition | |
1464 | * @secattr: the security attributes | |
1465 | * @buffer: the option buffer | |
1466 | * @buffer_len: length of buffer in bytes | |
1467 | * | |
1468 | * Description: | |
1469 | * Generate a CIPSO option using the local tag. Returns the size of the tag | |
1470 | * on success, negative values on failure. | |
1471 | * | |
1472 | */ | |
1473 | static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def, | |
1474 | const struct netlbl_lsm_secattr *secattr, | |
1475 | unsigned char *buffer, | |
1476 | u32 buffer_len) | |
1477 | { | |
1478 | if (!(secattr->flags & NETLBL_SECATTR_SECID)) | |
1479 | return -EPERM; | |
1480 | ||
1481 | buffer[0] = CIPSO_V4_TAG_LOCAL; | |
1482 | buffer[1] = CIPSO_V4_TAG_LOC_BLEN; | |
1483 | *(u32 *)&buffer[2] = secattr->attr.secid; | |
1484 | ||
1485 | return CIPSO_V4_TAG_LOC_BLEN; | |
1486 | } | |
1487 | ||
1488 | /** | |
1489 | * cipso_v4_parsetag_loc - Parse a CIPSO local tag | |
1490 | * @doi_def: the DOI definition | |
1491 | * @tag: the CIPSO tag | |
1492 | * @secattr: the security attributes | |
1493 | * | |
1494 | * Description: | |
1495 | * Parse a CIPSO local tag and return the security attributes in @secattr. | |
1496 | * Return zero on success, negatives values on failure. | |
1497 | * | |
1498 | */ | |
1499 | static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def, | |
1500 | const unsigned char *tag, | |
1501 | struct netlbl_lsm_secattr *secattr) | |
1502 | { | |
1503 | secattr->attr.secid = *(u32 *)&tag[2]; | |
1504 | secattr->flags |= NETLBL_SECATTR_SECID; | |
1505 | ||
1506 | return 0; | |
1507 | } | |
1508 | ||
04f81f01 PM |
1509 | /** |
1510 | * cipso_v4_optptr - Find the CIPSO option in the packet | |
1511 | * @skb: the packet | |
1512 | * | |
1513 | * Description: | |
1514 | * Parse the packet's IP header looking for a CIPSO option. Returns a pointer | |
1515 | * to the start of the CIPSO option on success, NULL if one if not found. | |
1516 | * | |
1517 | */ | |
1518 | unsigned char *cipso_v4_optptr(const struct sk_buff *skb) | |
1519 | { | |
1520 | const struct iphdr *iph = ip_hdr(skb); | |
1521 | unsigned char *optptr = (unsigned char *)&(ip_hdr(skb)[1]); | |
1522 | int optlen; | |
1523 | int taglen; | |
1524 | ||
1525 | for (optlen = iph->ihl*4 - sizeof(struct iphdr); optlen > 0; ) { | |
40413955 | 1526 | switch (optptr[0]) { |
1527 | case IPOPT_CIPSO: | |
04f81f01 | 1528 | return optptr; |
40413955 | 1529 | case IPOPT_END: |
1530 | return NULL; | |
1531 | case IPOPT_NOOP: | |
1532 | taglen = 1; | |
1533 | break; | |
1534 | default: | |
1535 | taglen = optptr[1]; | |
1536 | } | |
04f81f01 PM |
1537 | optlen -= taglen; |
1538 | optptr += taglen; | |
1539 | } | |
1540 | ||
1541 | return NULL; | |
1542 | } | |
1543 | ||
446fda4f PM |
1544 | /** |
1545 | * cipso_v4_validate - Validate a CIPSO option | |
1546 | * @option: the start of the option, on error it is set to point to the error | |
1547 | * | |
1548 | * Description: | |
1549 | * This routine is called to validate a CIPSO option, it checks all of the | |
1550 | * fields to ensure that they are at least valid, see the draft snippet below | |
1551 | * for details. If the option is valid then a zero value is returned and | |
1552 | * the value of @option is unchanged. If the option is invalid then a | |
1553 | * non-zero value is returned and @option is adjusted to point to the | |
1554 | * offending portion of the option. From the IETF draft ... | |
1555 | * | |
1556 | * "If any field within the CIPSO options, such as the DOI identifier, is not | |
1557 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' | |
1558 | * (type 12) is generated and returned. The ICMP code field is set to 'bad | |
1559 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field | |
1560 | * that is unrecognized." | |
1561 | * | |
1562 | */ | |
15c45f7b | 1563 | int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) |
446fda4f PM |
1564 | { |
1565 | unsigned char *opt = *option; | |
1566 | unsigned char *tag; | |
1567 | unsigned char opt_iter; | |
1568 | unsigned char err_offset = 0; | |
1569 | u8 opt_len; | |
1570 | u8 tag_len; | |
1571 | struct cipso_v4_doi *doi_def = NULL; | |
1572 | u32 tag_iter; | |
1573 | ||
1574 | /* caller already checks for length values that are too large */ | |
1575 | opt_len = opt[1]; | |
1576 | if (opt_len < 8) { | |
1577 | err_offset = 1; | |
1578 | goto validate_return; | |
1579 | } | |
1580 | ||
1581 | rcu_read_lock(); | |
d3e2ce3b | 1582 | doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2])); |
51456b29 | 1583 | if (!doi_def) { |
446fda4f PM |
1584 | err_offset = 2; |
1585 | goto validate_return_locked; | |
1586 | } | |
1587 | ||
15c45f7b | 1588 | opt_iter = CIPSO_V4_HDR_LEN; |
446fda4f PM |
1589 | tag = opt + opt_iter; |
1590 | while (opt_iter < opt_len) { | |
1591 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) | |
1592 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || | |
1593 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { | |
1594 | err_offset = opt_iter; | |
1595 | goto validate_return_locked; | |
1596 | } | |
1597 | ||
d71b7896 ED |
1598 | if (opt_iter + 1 == opt_len) { |
1599 | err_offset = opt_iter; | |
1600 | goto validate_return_locked; | |
1601 | } | |
446fda4f PM |
1602 | tag_len = tag[1]; |
1603 | if (tag_len > (opt_len - opt_iter)) { | |
1604 | err_offset = opt_iter + 1; | |
1605 | goto validate_return_locked; | |
1606 | } | |
1607 | ||
1608 | switch (tag[0]) { | |
1609 | case CIPSO_V4_TAG_RBITMAP: | |
15c45f7b | 1610 | if (tag_len < CIPSO_V4_TAG_RBM_BLEN) { |
446fda4f PM |
1611 | err_offset = opt_iter + 1; |
1612 | goto validate_return_locked; | |
1613 | } | |
1614 | ||
1615 | /* We are already going to do all the verification | |
1616 | * necessary at the socket layer so from our point of | |
1617 | * view it is safe to turn these checks off (and less | |
1618 | * work), however, the CIPSO draft says we should do | |
1619 | * all the CIPSO validations here but it doesn't | |
1620 | * really specify _exactly_ what we need to validate | |
1621 | * ... so, just make it a sysctl tunable. */ | |
1622 | if (cipso_v4_rbm_strictvalid) { | |
1623 | if (cipso_v4_map_lvl_valid(doi_def, | |
1624 | tag[3]) < 0) { | |
1625 | err_offset = opt_iter + 3; | |
1626 | goto validate_return_locked; | |
1627 | } | |
15c45f7b | 1628 | if (tag_len > CIPSO_V4_TAG_RBM_BLEN && |
446fda4f PM |
1629 | cipso_v4_map_cat_rbm_valid(doi_def, |
1630 | &tag[4], | |
1631 | tag_len - 4) < 0) { | |
1632 | err_offset = opt_iter + 4; | |
1633 | goto validate_return_locked; | |
1634 | } | |
1635 | } | |
1636 | break; | |
654bbc2a | 1637 | case CIPSO_V4_TAG_ENUM: |
15c45f7b | 1638 | if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) { |
654bbc2a PM |
1639 | err_offset = opt_iter + 1; |
1640 | goto validate_return_locked; | |
1641 | } | |
1642 | ||
1643 | if (cipso_v4_map_lvl_valid(doi_def, | |
1644 | tag[3]) < 0) { | |
1645 | err_offset = opt_iter + 3; | |
1646 | goto validate_return_locked; | |
1647 | } | |
15c45f7b | 1648 | if (tag_len > CIPSO_V4_TAG_ENUM_BLEN && |
654bbc2a PM |
1649 | cipso_v4_map_cat_enum_valid(doi_def, |
1650 | &tag[4], | |
1651 | tag_len - 4) < 0) { | |
1652 | err_offset = opt_iter + 4; | |
1653 | goto validate_return_locked; | |
1654 | } | |
1655 | break; | |
484b3669 | 1656 | case CIPSO_V4_TAG_RANGE: |
15c45f7b | 1657 | if (tag_len < CIPSO_V4_TAG_RNG_BLEN) { |
484b3669 PM |
1658 | err_offset = opt_iter + 1; |
1659 | goto validate_return_locked; | |
1660 | } | |
1661 | ||
1662 | if (cipso_v4_map_lvl_valid(doi_def, | |
1663 | tag[3]) < 0) { | |
1664 | err_offset = opt_iter + 3; | |
1665 | goto validate_return_locked; | |
1666 | } | |
15c45f7b | 1667 | if (tag_len > CIPSO_V4_TAG_RNG_BLEN && |
484b3669 PM |
1668 | cipso_v4_map_cat_rng_valid(doi_def, |
1669 | &tag[4], | |
1670 | tag_len - 4) < 0) { | |
1671 | err_offset = opt_iter + 4; | |
1672 | goto validate_return_locked; | |
1673 | } | |
1674 | break; | |
15c45f7b PM |
1675 | case CIPSO_V4_TAG_LOCAL: |
1676 | /* This is a non-standard tag that we only allow for | |
1677 | * local connections, so if the incoming interface is | |
89d7ae34 PM |
1678 | * not the loopback device drop the packet. Further, |
1679 | * there is no legitimate reason for setting this from | |
1680 | * userspace so reject it if skb is NULL. */ | |
51456b29 | 1681 | if (!skb || !(skb->dev->flags & IFF_LOOPBACK)) { |
15c45f7b PM |
1682 | err_offset = opt_iter; |
1683 | goto validate_return_locked; | |
1684 | } | |
1685 | if (tag_len != CIPSO_V4_TAG_LOC_BLEN) { | |
1686 | err_offset = opt_iter + 1; | |
1687 | goto validate_return_locked; | |
1688 | } | |
1689 | break; | |
446fda4f PM |
1690 | default: |
1691 | err_offset = opt_iter; | |
1692 | goto validate_return_locked; | |
1693 | } | |
1694 | ||
1695 | tag += tag_len; | |
1696 | opt_iter += tag_len; | |
1697 | } | |
1698 | ||
1699 | validate_return_locked: | |
1700 | rcu_read_unlock(); | |
1701 | validate_return: | |
1702 | *option = opt + err_offset; | |
1703 | return err_offset; | |
1704 | } | |
1705 | ||
1706 | /** | |
25985edc | 1707 | * cipso_v4_error - Send the correct response for a bad packet |
446fda4f PM |
1708 | * @skb: the packet |
1709 | * @error: the error code | |
1710 | * @gateway: CIPSO gateway flag | |
1711 | * | |
1712 | * Description: | |
1713 | * Based on the error code given in @error, send an ICMP error message back to | |
1714 | * the originating host. From the IETF draft ... | |
1715 | * | |
1716 | * "If the contents of the CIPSO [option] are valid but the security label is | |
1717 | * outside of the configured host or port label range, the datagram is | |
1718 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and | |
1719 | * returned. The code field of the ICMP is set to 'communication with | |
1720 | * destination network administratively prohibited' (code 9) or to | |
1721 | * 'communication with destination host administratively prohibited' | |
1722 | * (code 10). The value of the code is dependent on whether the originator | |
1723 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The | |
1724 | * recipient of the ICMP message MUST be able to handle either value. The | |
1725 | * same procedure is performed if a CIPSO [option] can not be added to an | |
1726 | * IP packet because it is too large to fit in the IP options area." | |
1727 | * | |
1728 | * "If the error is triggered by receipt of an ICMP message, the message is | |
1729 | * discarded and no response is permitted (consistent with general ICMP | |
1730 | * processing rules)." | |
1731 | * | |
1732 | */ | |
1733 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) | |
1734 | { | |
eddc9ec5 | 1735 | if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) |
446fda4f PM |
1736 | return; |
1737 | ||
1738 | if (gateway) | |
1739 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0); | |
1740 | else | |
1741 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0); | |
1742 | } | |
1743 | ||
1744 | /** | |
948bf85c PM |
1745 | * cipso_v4_genopt - Generate a CIPSO option |
1746 | * @buf: the option buffer | |
1747 | * @buf_len: the size of opt_buf | |
446fda4f | 1748 | * @doi_def: the CIPSO DOI to use |
948bf85c | 1749 | * @secattr: the security attributes |
446fda4f PM |
1750 | * |
1751 | * Description: | |
948bf85c PM |
1752 | * Generate a CIPSO option using the DOI definition and security attributes |
1753 | * passed to the function. Returns the length of the option on success and | |
1754 | * negative values on failure. | |
446fda4f PM |
1755 | * |
1756 | */ | |
948bf85c PM |
1757 | static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, |
1758 | const struct cipso_v4_doi *doi_def, | |
1759 | const struct netlbl_lsm_secattr *secattr) | |
446fda4f | 1760 | { |
948bf85c | 1761 | int ret_val; |
446fda4f | 1762 | u32 iter; |
446fda4f | 1763 | |
948bf85c PM |
1764 | if (buf_len <= CIPSO_V4_HDR_LEN) |
1765 | return -ENOSPC; | |
91b1ed0a | 1766 | |
446fda4f PM |
1767 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1768 | * really a good assumption to make but since we only support the MAC | |
1769 | * tags right now it is a safe assumption. */ | |
1770 | iter = 0; | |
1771 | do { | |
91b1ed0a | 1772 | memset(buf, 0, buf_len); |
446fda4f PM |
1773 | switch (doi_def->tags[iter]) { |
1774 | case CIPSO_V4_TAG_RBITMAP: | |
1775 | ret_val = cipso_v4_gentag_rbm(doi_def, | |
91b1ed0a PM |
1776 | secattr, |
1777 | &buf[CIPSO_V4_HDR_LEN], | |
1778 | buf_len - CIPSO_V4_HDR_LEN); | |
446fda4f | 1779 | break; |
654bbc2a PM |
1780 | case CIPSO_V4_TAG_ENUM: |
1781 | ret_val = cipso_v4_gentag_enum(doi_def, | |
1782 | secattr, | |
1783 | &buf[CIPSO_V4_HDR_LEN], | |
1784 | buf_len - CIPSO_V4_HDR_LEN); | |
1785 | break; | |
484b3669 PM |
1786 | case CIPSO_V4_TAG_RANGE: |
1787 | ret_val = cipso_v4_gentag_rng(doi_def, | |
1788 | secattr, | |
1789 | &buf[CIPSO_V4_HDR_LEN], | |
1790 | buf_len - CIPSO_V4_HDR_LEN); | |
1791 | break; | |
15c45f7b PM |
1792 | case CIPSO_V4_TAG_LOCAL: |
1793 | ret_val = cipso_v4_gentag_loc(doi_def, | |
1794 | secattr, | |
1795 | &buf[CIPSO_V4_HDR_LEN], | |
1796 | buf_len - CIPSO_V4_HDR_LEN); | |
1797 | break; | |
446fda4f | 1798 | default: |
948bf85c | 1799 | return -EPERM; |
446fda4f PM |
1800 | } |
1801 | ||
1802 | iter++; | |
91b1ed0a | 1803 | } while (ret_val < 0 && |
446fda4f PM |
1804 | iter < CIPSO_V4_TAG_MAXCNT && |
1805 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); | |
91b1ed0a | 1806 | if (ret_val < 0) |
948bf85c | 1807 | return ret_val; |
91b1ed0a | 1808 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
948bf85c PM |
1809 | return CIPSO_V4_HDR_LEN + ret_val; |
1810 | } | |
1811 | ||
1812 | /** | |
1813 | * cipso_v4_sock_setattr - Add a CIPSO option to a socket | |
1814 | * @sk: the socket | |
1815 | * @doi_def: the CIPSO DOI to use | |
1816 | * @secattr: the specific security attributes of the socket | |
1817 | * | |
1818 | * Description: | |
1819 | * Set the CIPSO option on the given socket using the DOI definition and | |
1820 | * security attributes passed to the function. This function requires | |
1821 | * exclusive access to @sk, which means it either needs to be in the | |
1822 | * process of being created or locked. Returns zero on success and negative | |
1823 | * values on failure. | |
1824 | * | |
1825 | */ | |
1826 | int cipso_v4_sock_setattr(struct sock *sk, | |
1827 | const struct cipso_v4_doi *doi_def, | |
1828 | const struct netlbl_lsm_secattr *secattr) | |
1829 | { | |
1830 | int ret_val = -EPERM; | |
1831 | unsigned char *buf = NULL; | |
1832 | u32 buf_len; | |
1833 | u32 opt_len; | |
f6d8bd05 | 1834 | struct ip_options_rcu *old, *opt = NULL; |
948bf85c PM |
1835 | struct inet_sock *sk_inet; |
1836 | struct inet_connection_sock *sk_conn; | |
1837 | ||
1838 | /* In the case of sock_create_lite(), the sock->sk field is not | |
1839 | * defined yet but it is not a problem as the only users of these | |
1840 | * "lite" PF_INET sockets are functions which do an accept() call | |
1841 | * afterwards so we will label the socket as part of the accept(). */ | |
51456b29 | 1842 | if (!sk) |
948bf85c PM |
1843 | return 0; |
1844 | ||
1845 | /* We allocate the maximum CIPSO option size here so we are probably | |
1846 | * being a little wasteful, but it makes our life _much_ easier later | |
1847 | * on and after all we are only talking about 40 bytes. */ | |
1848 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1849 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
51456b29 | 1850 | if (!buf) { |
948bf85c PM |
1851 | ret_val = -ENOMEM; |
1852 | goto socket_setattr_failure; | |
1853 | } | |
1854 | ||
1855 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1856 | if (ret_val < 0) | |
1857 | goto socket_setattr_failure; | |
1858 | buf_len = ret_val; | |
446fda4f PM |
1859 | |
1860 | /* We can't use ip_options_get() directly because it makes a call to | |
1861 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
f8687afe PM |
1862 | * we won't always have CAP_NET_RAW even though we _always_ want to |
1863 | * set the IPOPT_CIPSO option. */ | |
446fda4f PM |
1864 | opt_len = (buf_len + 3) & ~3; |
1865 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
51456b29 | 1866 | if (!opt) { |
446fda4f PM |
1867 | ret_val = -ENOMEM; |
1868 | goto socket_setattr_failure; | |
1869 | } | |
f6d8bd05 ED |
1870 | memcpy(opt->opt.__data, buf, buf_len); |
1871 | opt->opt.optlen = opt_len; | |
1872 | opt->opt.cipso = sizeof(struct iphdr); | |
446fda4f PM |
1873 | kfree(buf); |
1874 | buf = NULL; | |
446fda4f PM |
1875 | |
1876 | sk_inet = inet_sk(sk); | |
f6d8bd05 | 1877 | |
1e1d04e6 HFS |
1878 | old = rcu_dereference_protected(sk_inet->inet_opt, |
1879 | lockdep_sock_is_held(sk)); | |
446fda4f PM |
1880 | if (sk_inet->is_icsk) { |
1881 | sk_conn = inet_csk(sk); | |
f6d8bd05 ED |
1882 | if (old) |
1883 | sk_conn->icsk_ext_hdr_len -= old->opt.optlen; | |
1884 | sk_conn->icsk_ext_hdr_len += opt->opt.optlen; | |
446fda4f PM |
1885 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); |
1886 | } | |
f6d8bd05 ED |
1887 | rcu_assign_pointer(sk_inet->inet_opt, opt); |
1888 | if (old) | |
4f9c8c1b | 1889 | kfree_rcu(old, rcu); |
446fda4f PM |
1890 | |
1891 | return 0; | |
1892 | ||
1893 | socket_setattr_failure: | |
1894 | kfree(buf); | |
1895 | kfree(opt); | |
1896 | return ret_val; | |
1897 | } | |
1898 | ||
014ab19a | 1899 | /** |
389fb800 PM |
1900 | * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket |
1901 | * @req: the connection request socket | |
1902 | * @doi_def: the CIPSO DOI to use | |
1903 | * @secattr: the specific security attributes of the socket | |
014ab19a PM |
1904 | * |
1905 | * Description: | |
389fb800 PM |
1906 | * Set the CIPSO option on the given socket using the DOI definition and |
1907 | * security attributes passed to the function. Returns zero on success and | |
1908 | * negative values on failure. | |
014ab19a PM |
1909 | * |
1910 | */ | |
389fb800 PM |
1911 | int cipso_v4_req_setattr(struct request_sock *req, |
1912 | const struct cipso_v4_doi *doi_def, | |
1913 | const struct netlbl_lsm_secattr *secattr) | |
014ab19a | 1914 | { |
389fb800 PM |
1915 | int ret_val = -EPERM; |
1916 | unsigned char *buf = NULL; | |
1917 | u32 buf_len; | |
1918 | u32 opt_len; | |
f6d8bd05 | 1919 | struct ip_options_rcu *opt = NULL; |
389fb800 | 1920 | struct inet_request_sock *req_inet; |
014ab19a | 1921 | |
389fb800 PM |
1922 | /* We allocate the maximum CIPSO option size here so we are probably |
1923 | * being a little wasteful, but it makes our life _much_ easier later | |
1924 | * on and after all we are only talking about 40 bytes. */ | |
1925 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1926 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
51456b29 | 1927 | if (!buf) { |
389fb800 PM |
1928 | ret_val = -ENOMEM; |
1929 | goto req_setattr_failure; | |
1930 | } | |
1931 | ||
1932 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1933 | if (ret_val < 0) | |
1934 | goto req_setattr_failure; | |
1935 | buf_len = ret_val; | |
1936 | ||
1937 | /* We can't use ip_options_get() directly because it makes a call to | |
1938 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
1939 | * we won't always have CAP_NET_RAW even though we _always_ want to | |
1940 | * set the IPOPT_CIPSO option. */ | |
1941 | opt_len = (buf_len + 3) & ~3; | |
1942 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
51456b29 | 1943 | if (!opt) { |
389fb800 PM |
1944 | ret_val = -ENOMEM; |
1945 | goto req_setattr_failure; | |
1946 | } | |
f6d8bd05 ED |
1947 | memcpy(opt->opt.__data, buf, buf_len); |
1948 | opt->opt.optlen = opt_len; | |
1949 | opt->opt.cipso = sizeof(struct iphdr); | |
389fb800 PM |
1950 | kfree(buf); |
1951 | buf = NULL; | |
1952 | ||
1953 | req_inet = inet_rsk(req); | |
c92e8c02 | 1954 | opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt); |
f6d8bd05 | 1955 | if (opt) |
4f9c8c1b | 1956 | kfree_rcu(opt, rcu); |
389fb800 PM |
1957 | |
1958 | return 0; | |
1959 | ||
1960 | req_setattr_failure: | |
1961 | kfree(buf); | |
1962 | kfree(opt); | |
1963 | return ret_val; | |
1964 | } | |
1965 | ||
1966 | /** | |
1967 | * cipso_v4_delopt - Delete the CIPSO option from a set of IP options | |
1968 | * @opt_ptr: IP option pointer | |
1969 | * | |
1970 | * Description: | |
1971 | * Deletes the CIPSO IP option from a set of IP options and makes the necessary | |
1972 | * adjustments to the IP option structure. Returns zero on success, negative | |
1973 | * values on failure. | |
1974 | * | |
1975 | */ | |
c92e8c02 | 1976 | static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr) |
389fb800 | 1977 | { |
c92e8c02 | 1978 | struct ip_options_rcu *opt = rcu_dereference_protected(*opt_ptr, 1); |
389fb800 | 1979 | int hdr_delta = 0; |
014ab19a | 1980 | |
c92e8c02 ED |
1981 | if (!opt || opt->opt.cipso == 0) |
1982 | return 0; | |
f6d8bd05 | 1983 | if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) { |
014ab19a PM |
1984 | u8 cipso_len; |
1985 | u8 cipso_off; | |
1986 | unsigned char *cipso_ptr; | |
1987 | int iter; | |
1988 | int optlen_new; | |
1989 | ||
f6d8bd05 ED |
1990 | cipso_off = opt->opt.cipso - sizeof(struct iphdr); |
1991 | cipso_ptr = &opt->opt.__data[cipso_off]; | |
014ab19a PM |
1992 | cipso_len = cipso_ptr[1]; |
1993 | ||
f6d8bd05 ED |
1994 | if (opt->opt.srr > opt->opt.cipso) |
1995 | opt->opt.srr -= cipso_len; | |
1996 | if (opt->opt.rr > opt->opt.cipso) | |
1997 | opt->opt.rr -= cipso_len; | |
1998 | if (opt->opt.ts > opt->opt.cipso) | |
1999 | opt->opt.ts -= cipso_len; | |
2000 | if (opt->opt.router_alert > opt->opt.cipso) | |
2001 | opt->opt.router_alert -= cipso_len; | |
2002 | opt->opt.cipso = 0; | |
014ab19a PM |
2003 | |
2004 | memmove(cipso_ptr, cipso_ptr + cipso_len, | |
f6d8bd05 | 2005 | opt->opt.optlen - cipso_off - cipso_len); |
014ab19a PM |
2006 | |
2007 | /* determining the new total option length is tricky because of | |
2008 | * the padding necessary, the only thing i can think to do at | |
2009 | * this point is walk the options one-by-one, skipping the | |
2010 | * padding at the end to determine the actual option size and | |
2011 | * from there we can determine the new total option length */ | |
2012 | iter = 0; | |
2013 | optlen_new = 0; | |
f6d8bd05 ED |
2014 | while (iter < opt->opt.optlen) |
2015 | if (opt->opt.__data[iter] != IPOPT_NOP) { | |
2016 | iter += opt->opt.__data[iter + 1]; | |
014ab19a PM |
2017 | optlen_new = iter; |
2018 | } else | |
2019 | iter++; | |
f6d8bd05 ED |
2020 | hdr_delta = opt->opt.optlen; |
2021 | opt->opt.optlen = (optlen_new + 3) & ~3; | |
2022 | hdr_delta -= opt->opt.optlen; | |
014ab19a PM |
2023 | } else { |
2024 | /* only the cipso option was present on the socket so we can | |
2025 | * remove the entire option struct */ | |
389fb800 | 2026 | *opt_ptr = NULL; |
f6d8bd05 | 2027 | hdr_delta = opt->opt.optlen; |
4f9c8c1b | 2028 | kfree_rcu(opt, rcu); |
014ab19a PM |
2029 | } |
2030 | ||
389fb800 PM |
2031 | return hdr_delta; |
2032 | } | |
2033 | ||
2034 | /** | |
2035 | * cipso_v4_sock_delattr - Delete the CIPSO option from a socket | |
2036 | * @sk: the socket | |
2037 | * | |
2038 | * Description: | |
2039 | * Removes the CIPSO option from a socket, if present. | |
2040 | * | |
2041 | */ | |
2042 | void cipso_v4_sock_delattr(struct sock *sk) | |
2043 | { | |
389fb800 | 2044 | struct inet_sock *sk_inet; |
c92e8c02 | 2045 | int hdr_delta; |
389fb800 PM |
2046 | |
2047 | sk_inet = inet_sk(sk); | |
389fb800 | 2048 | |
f6d8bd05 | 2049 | hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt); |
014ab19a PM |
2050 | if (sk_inet->is_icsk && hdr_delta > 0) { |
2051 | struct inet_connection_sock *sk_conn = inet_csk(sk); | |
2052 | sk_conn->icsk_ext_hdr_len -= hdr_delta; | |
2053 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
2054 | } | |
2055 | } | |
2056 | ||
389fb800 PM |
2057 | /** |
2058 | * cipso_v4_req_delattr - Delete the CIPSO option from a request socket | |
2059 | * @reg: the request socket | |
2060 | * | |
2061 | * Description: | |
2062 | * Removes the CIPSO option from a request socket, if present. | |
2063 | * | |
2064 | */ | |
2065 | void cipso_v4_req_delattr(struct request_sock *req) | |
2066 | { | |
c92e8c02 | 2067 | cipso_v4_delopt(&inet_rsk(req)->ireq_opt); |
389fb800 PM |
2068 | } |
2069 | ||
446fda4f | 2070 | /** |
63d804ea PM |
2071 | * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions |
2072 | * @cipso: the CIPSO v4 option | |
446fda4f PM |
2073 | * @secattr: the security attributes |
2074 | * | |
2075 | * Description: | |
63d804ea PM |
2076 | * Inspect @cipso and return the security attributes in @secattr. Returns zero |
2077 | * on success and negative values on failure. | |
446fda4f PM |
2078 | * |
2079 | */ | |
04f81f01 PM |
2080 | int cipso_v4_getattr(const unsigned char *cipso, |
2081 | struct netlbl_lsm_secattr *secattr) | |
446fda4f PM |
2082 | { |
2083 | int ret_val = -ENOMSG; | |
446fda4f PM |
2084 | u32 doi; |
2085 | struct cipso_v4_doi *doi_def; | |
2086 | ||
63d804ea PM |
2087 | if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0) |
2088 | return 0; | |
446fda4f | 2089 | |
d3e2ce3b | 2090 | doi = get_unaligned_be32(&cipso[2]); |
446fda4f | 2091 | rcu_read_lock(); |
9bb5fd2b | 2092 | doi_def = cipso_v4_doi_search(doi); |
51456b29 | 2093 | if (!doi_def) |
63d804ea | 2094 | goto getattr_return; |
91b1ed0a PM |
2095 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
2096 | * really a good assumption to make but since we only support the MAC | |
2097 | * tags right now it is a safe assumption. */ | |
63d804ea | 2098 | switch (cipso[6]) { |
446fda4f | 2099 | case CIPSO_V4_TAG_RBITMAP: |
63d804ea | 2100 | ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr); |
446fda4f | 2101 | break; |
654bbc2a | 2102 | case CIPSO_V4_TAG_ENUM: |
63d804ea | 2103 | ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr); |
654bbc2a | 2104 | break; |
484b3669 | 2105 | case CIPSO_V4_TAG_RANGE: |
63d804ea | 2106 | ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr); |
484b3669 | 2107 | break; |
15c45f7b PM |
2108 | case CIPSO_V4_TAG_LOCAL: |
2109 | ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr); | |
2110 | break; | |
446fda4f | 2111 | } |
16efd454 PM |
2112 | if (ret_val == 0) |
2113 | secattr->type = NETLBL_NLTYPE_CIPSOV4; | |
446fda4f | 2114 | |
63d804ea PM |
2115 | getattr_return: |
2116 | rcu_read_unlock(); | |
14a72f53 PM |
2117 | return ret_val; |
2118 | } | |
2119 | ||
63d804ea PM |
2120 | /** |
2121 | * cipso_v4_sock_getattr - Get the security attributes from a sock | |
2122 | * @sk: the sock | |
2123 | * @secattr: the security attributes | |
2124 | * | |
2125 | * Description: | |
2126 | * Query @sk to see if there is a CIPSO option attached to the sock and if | |
2127 | * there is return the CIPSO security attributes in @secattr. This function | |
2128 | * requires that @sk be locked, or privately held, but it does not do any | |
2129 | * locking itself. Returns zero on success and negative values on failure. | |
2130 | * | |
2131 | */ | |
2132 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) | |
2133 | { | |
f6d8bd05 ED |
2134 | struct ip_options_rcu *opt; |
2135 | int res = -ENOMSG; | |
63d804ea | 2136 | |
f6d8bd05 ED |
2137 | rcu_read_lock(); |
2138 | opt = rcu_dereference(inet_sk(sk)->inet_opt); | |
2139 | if (opt && opt->opt.cipso) | |
2140 | res = cipso_v4_getattr(opt->opt.__data + | |
2141 | opt->opt.cipso - | |
2142 | sizeof(struct iphdr), | |
2143 | secattr); | |
2144 | rcu_read_unlock(); | |
2145 | return res; | |
63d804ea PM |
2146 | } |
2147 | ||
948bf85c PM |
2148 | /** |
2149 | * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet | |
2150 | * @skb: the packet | |
2151 | * @secattr: the security attributes | |
2152 | * | |
2153 | * Description: | |
2154 | * Set the CIPSO option on the given packet based on the security attributes. | |
2155 | * Returns a pointer to the IP header on success and NULL on failure. | |
2156 | * | |
2157 | */ | |
2158 | int cipso_v4_skbuff_setattr(struct sk_buff *skb, | |
2159 | const struct cipso_v4_doi *doi_def, | |
2160 | const struct netlbl_lsm_secattr *secattr) | |
2161 | { | |
2162 | int ret_val; | |
2163 | struct iphdr *iph; | |
2164 | struct ip_options *opt = &IPCB(skb)->opt; | |
2165 | unsigned char buf[CIPSO_V4_OPT_LEN_MAX]; | |
2166 | u32 buf_len = CIPSO_V4_OPT_LEN_MAX; | |
2167 | u32 opt_len; | |
2168 | int len_delta; | |
2169 | ||
00af5c69 | 2170 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); |
2171 | if (ret_val < 0) | |
2172 | return ret_val; | |
2173 | buf_len = ret_val; | |
948bf85c PM |
2174 | opt_len = (buf_len + 3) & ~3; |
2175 | ||
2176 | /* we overwrite any existing options to ensure that we have enough | |
2177 | * room for the CIPSO option, the reason is that we _need_ to guarantee | |
2178 | * that the security label is applied to the packet - we do the same | |
2179 | * thing when using the socket options and it hasn't caused a problem, | |
2180 | * if we need to we can always revisit this choice later */ | |
2181 | ||
2182 | len_delta = opt_len - opt->optlen; | |
2183 | /* if we don't ensure enough headroom we could panic on the skb_push() | |
2184 | * call below so make sure we have enough, we are also "mangling" the | |
2185 | * packet so we should probably do a copy-on-write call anyway */ | |
2186 | ret_val = skb_cow(skb, skb_headroom(skb) + len_delta); | |
2187 | if (ret_val < 0) | |
2188 | return ret_val; | |
2189 | ||
2190 | if (len_delta > 0) { | |
2191 | /* we assume that the header + opt->optlen have already been | |
2192 | * "pushed" in ip_options_build() or similar */ | |
2193 | iph = ip_hdr(skb); | |
2194 | skb_push(skb, len_delta); | |
2195 | memmove((char *)iph - len_delta, iph, iph->ihl << 2); | |
2196 | skb_reset_network_header(skb); | |
2197 | iph = ip_hdr(skb); | |
2198 | } else if (len_delta < 0) { | |
2199 | iph = ip_hdr(skb); | |
2200 | memset(iph + 1, IPOPT_NOP, opt->optlen); | |
2201 | } else | |
2202 | iph = ip_hdr(skb); | |
2203 | ||
2204 | if (opt->optlen > 0) | |
2205 | memset(opt, 0, sizeof(*opt)); | |
2206 | opt->optlen = opt_len; | |
2207 | opt->cipso = sizeof(struct iphdr); | |
2208 | opt->is_changed = 1; | |
2209 | ||
2210 | /* we have to do the following because we are being called from a | |
2211 | * netfilter hook which means the packet already has had the header | |
2212 | * fields populated and the checksum calculated - yes this means we | |
2213 | * are doing more work than needed but we do it to keep the core | |
2214 | * stack clean and tidy */ | |
2215 | memcpy(iph + 1, buf, buf_len); | |
2216 | if (opt_len > buf_len) | |
2217 | memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); | |
2218 | if (len_delta != 0) { | |
2219 | iph->ihl = 5 + (opt_len >> 2); | |
2220 | iph->tot_len = htons(skb->len); | |
2221 | } | |
2222 | ip_send_check(iph); | |
2223 | ||
2224 | return 0; | |
2225 | } | |
2226 | ||
2227 | /** | |
2228 | * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet | |
2229 | * @skb: the packet | |
2230 | * | |
2231 | * Description: | |
2232 | * Removes any and all CIPSO options from the given packet. Returns zero on | |
2233 | * success, negative values on failure. | |
2234 | * | |
2235 | */ | |
2236 | int cipso_v4_skbuff_delattr(struct sk_buff *skb) | |
2237 | { | |
2238 | int ret_val; | |
2239 | struct iphdr *iph; | |
2240 | struct ip_options *opt = &IPCB(skb)->opt; | |
2241 | unsigned char *cipso_ptr; | |
2242 | ||
2243 | if (opt->cipso == 0) | |
2244 | return 0; | |
2245 | ||
2246 | /* since we are changing the packet we should make a copy */ | |
2247 | ret_val = skb_cow(skb, skb_headroom(skb)); | |
2248 | if (ret_val < 0) | |
2249 | return ret_val; | |
2250 | ||
2251 | /* the easiest thing to do is just replace the cipso option with noop | |
2252 | * options since we don't change the size of the packet, although we | |
2253 | * still need to recalculate the checksum */ | |
2254 | ||
2255 | iph = ip_hdr(skb); | |
2256 | cipso_ptr = (unsigned char *)iph + opt->cipso; | |
2257 | memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); | |
2258 | opt->cipso = 0; | |
2259 | opt->is_changed = 1; | |
2260 | ||
2261 | ip_send_check(iph); | |
2262 | ||
2263 | return 0; | |
2264 | } | |
2265 | ||
446fda4f PM |
2266 | /* |
2267 | * Setup Functions | |
2268 | */ | |
2269 | ||
2270 | /** | |
2271 | * cipso_v4_init - Initialize the CIPSO module | |
2272 | * | |
2273 | * Description: | |
2274 | * Initialize the CIPSO module and prepare it for use. Returns zero on success | |
2275 | * and negative values on failure. | |
2276 | * | |
2277 | */ | |
2278 | static int __init cipso_v4_init(void) | |
2279 | { | |
2280 | int ret_val; | |
2281 | ||
2282 | ret_val = cipso_v4_cache_init(); | |
2283 | if (ret_val != 0) | |
2284 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", | |
2285 | ret_val); | |
2286 | ||
2287 | return 0; | |
2288 | } | |
2289 | ||
2290 | subsys_initcall(cipso_v4_init); |