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1ccea77e | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
446fda4f PM |
2 | /* |
3 | * CIPSO - Commercial IP Security Option | |
4 | * | |
5 | * This is an implementation of the CIPSO 2.2 protocol as specified in | |
6 | * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in | |
586c2500 | 7 | * FIPS-188. While CIPSO never became a full IETF RFC standard many vendors |
446fda4f PM |
8 | * have chosen to adopt the protocol and over the years it has become a |
9 | * de-facto standard for labeled networking. | |
10 | * | |
586c2500 PM |
11 | * The CIPSO draft specification can be found in the kernel's Documentation |
12 | * directory as well as the following URL: | |
631dd1a8 | 13 | * http://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt |
586c2500 PM |
14 | * The FIPS-188 specification can be found at the following URL: |
15 | * http://www.itl.nist.gov/fipspubs/fip188.htm | |
16 | * | |
446fda4f | 17 | * Author: Paul Moore <paul.moore@hp.com> |
446fda4f PM |
18 | */ |
19 | ||
20 | /* | |
948bf85c | 21 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 |
446fda4f PM |
22 | */ |
23 | ||
24 | #include <linux/init.h> | |
25 | #include <linux/types.h> | |
26 | #include <linux/rcupdate.h> | |
27 | #include <linux/list.h> | |
28 | #include <linux/spinlock.h> | |
29 | #include <linux/string.h> | |
30 | #include <linux/jhash.h> | |
6c2e8ac0 | 31 | #include <linux/audit.h> |
5a0e3ad6 | 32 | #include <linux/slab.h> |
446fda4f PM |
33 | #include <net/ip.h> |
34 | #include <net/icmp.h> | |
35 | #include <net/tcp.h> | |
36 | #include <net/netlabel.h> | |
37 | #include <net/cipso_ipv4.h> | |
60063497 | 38 | #include <linux/atomic.h> |
4c787b16 | 39 | #include <linux/bug.h> |
50e5d35c | 40 | #include <asm/unaligned.h> |
446fda4f | 41 | |
446fda4f | 42 | /* List of available DOI definitions */ |
446fda4f PM |
43 | /* XXX - This currently assumes a minimal number of different DOIs in use, |
44 | * if in practice there are a lot of different DOIs this list should | |
45 | * probably be turned into a hash table or something similar so we | |
46 | * can do quick lookups. */ | |
8ce11e6a | 47 | static DEFINE_SPINLOCK(cipso_v4_doi_list_lock); |
1596c97a | 48 | static LIST_HEAD(cipso_v4_doi_list); |
446fda4f PM |
49 | |
50 | /* Label mapping cache */ | |
51 | int cipso_v4_cache_enabled = 1; | |
52 | int cipso_v4_cache_bucketsize = 10; | |
53 | #define CIPSO_V4_CACHE_BUCKETBITS 7 | |
54 | #define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS) | |
55 | #define CIPSO_V4_CACHE_REORDERLIMIT 10 | |
56 | struct cipso_v4_map_cache_bkt { | |
57 | spinlock_t lock; | |
58 | u32 size; | |
59 | struct list_head list; | |
60 | }; | |
988b1343 | 61 | |
446fda4f PM |
62 | struct cipso_v4_map_cache_entry { |
63 | u32 hash; | |
64 | unsigned char *key; | |
65 | size_t key_len; | |
66 | ||
ffb733c6 | 67 | struct netlbl_lsm_cache *lsm_data; |
446fda4f PM |
68 | |
69 | u32 activity; | |
70 | struct list_head list; | |
71 | }; | |
988b1343 FF |
72 | |
73 | static struct cipso_v4_map_cache_bkt *cipso_v4_cache; | |
446fda4f PM |
74 | |
75 | /* Restricted bitmap (tag #1) flags */ | |
76 | int cipso_v4_rbm_optfmt = 0; | |
77 | int cipso_v4_rbm_strictvalid = 1; | |
78 | ||
f998e8cb PM |
79 | /* |
80 | * Protocol Constants | |
81 | */ | |
82 | ||
83 | /* Maximum size of the CIPSO IP option, derived from the fact that the maximum | |
84 | * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */ | |
85 | #define CIPSO_V4_OPT_LEN_MAX 40 | |
86 | ||
87 | /* Length of the base CIPSO option, this includes the option type (1 byte), the | |
88 | * option length (1 byte), and the DOI (4 bytes). */ | |
89 | #define CIPSO_V4_HDR_LEN 6 | |
90 | ||
91 | /* Base length of the restrictive category bitmap tag (tag #1). */ | |
92 | #define CIPSO_V4_TAG_RBM_BLEN 4 | |
93 | ||
94 | /* Base length of the enumerated category tag (tag #2). */ | |
95 | #define CIPSO_V4_TAG_ENUM_BLEN 4 | |
96 | ||
97 | /* Base length of the ranged categories bitmap tag (tag #5). */ | |
98 | #define CIPSO_V4_TAG_RNG_BLEN 4 | |
99 | /* The maximum number of category ranges permitted in the ranged category tag | |
100 | * (tag #5). You may note that the IETF draft states that the maximum number | |
101 | * of category ranges is 7, but if the low end of the last category range is | |
25985edc | 102 | * zero then it is possible to fit 8 category ranges because the zero should |
f998e8cb PM |
103 | * be omitted. */ |
104 | #define CIPSO_V4_TAG_RNG_CAT_MAX 8 | |
105 | ||
15c45f7b PM |
106 | /* Base length of the local tag (non-standard tag). |
107 | * Tag definition (may change between kernel versions) | |
108 | * | |
109 | * 0 8 16 24 32 | |
110 | * +----------+----------+----------+----------+ | |
111 | * | 10000000 | 00000110 | 32-bit secid value | | |
112 | * +----------+----------+----------+----------+ | |
113 | * | in (host byte order)| | |
114 | * +----------+----------+ | |
115 | * | |
116 | */ | |
117 | #define CIPSO_V4_TAG_LOC_BLEN 6 | |
118 | ||
446fda4f PM |
119 | /* |
120 | * Helper Functions | |
121 | */ | |
122 | ||
446fda4f PM |
123 | /** |
124 | * cipso_v4_cache_entry_free - Frees a cache entry | |
125 | * @entry: the entry to free | |
126 | * | |
127 | * Description: | |
ffb733c6 PM |
128 | * This function frees the memory associated with a cache entry including the |
129 | * LSM cache data if there are no longer any users, i.e. reference count == 0. | |
446fda4f PM |
130 | * |
131 | */ | |
132 | static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) | |
133 | { | |
ffb733c6 PM |
134 | if (entry->lsm_data) |
135 | netlbl_secattr_cache_free(entry->lsm_data); | |
446fda4f PM |
136 | kfree(entry->key); |
137 | kfree(entry); | |
138 | } | |
139 | ||
140 | /** | |
141 | * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache | |
142 | * @key: the hash key | |
143 | * @key_len: the length of the key in bytes | |
144 | * | |
145 | * Description: | |
146 | * The CIPSO tag hashing function. Returns a 32-bit hash value. | |
147 | * | |
148 | */ | |
149 | static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) | |
150 | { | |
151 | return jhash(key, key_len, 0); | |
152 | } | |
153 | ||
154 | /* | |
155 | * Label Mapping Cache Functions | |
156 | */ | |
157 | ||
158 | /** | |
159 | * cipso_v4_cache_init - Initialize the CIPSO cache | |
160 | * | |
161 | * Description: | |
162 | * Initializes the CIPSO label mapping cache, this function should be called | |
163 | * before any of the other functions defined in this file. Returns zero on | |
164 | * success, negative values on error. | |
165 | * | |
166 | */ | |
cb57659a | 167 | static int __init cipso_v4_cache_init(void) |
446fda4f PM |
168 | { |
169 | u32 iter; | |
170 | ||
171 | cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS, | |
172 | sizeof(struct cipso_v4_map_cache_bkt), | |
173 | GFP_KERNEL); | |
51456b29 | 174 | if (!cipso_v4_cache) |
446fda4f PM |
175 | return -ENOMEM; |
176 | ||
177 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
178 | spin_lock_init(&cipso_v4_cache[iter].lock); | |
179 | cipso_v4_cache[iter].size = 0; | |
180 | INIT_LIST_HEAD(&cipso_v4_cache[iter].list); | |
181 | } | |
182 | ||
183 | return 0; | |
184 | } | |
185 | ||
186 | /** | |
187 | * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache | |
188 | * | |
189 | * Description: | |
190 | * Invalidates and frees any entries in the CIPSO cache. Returns zero on | |
191 | * success and negative values on failure. | |
192 | * | |
193 | */ | |
194 | void cipso_v4_cache_invalidate(void) | |
195 | { | |
196 | struct cipso_v4_map_cache_entry *entry, *tmp_entry; | |
197 | u32 iter; | |
198 | ||
199 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { | |
609c92fe | 200 | spin_lock_bh(&cipso_v4_cache[iter].lock); |
446fda4f PM |
201 | list_for_each_entry_safe(entry, |
202 | tmp_entry, | |
203 | &cipso_v4_cache[iter].list, list) { | |
204 | list_del(&entry->list); | |
205 | cipso_v4_cache_entry_free(entry); | |
206 | } | |
207 | cipso_v4_cache[iter].size = 0; | |
609c92fe | 208 | spin_unlock_bh(&cipso_v4_cache[iter].lock); |
446fda4f | 209 | } |
446fda4f PM |
210 | } |
211 | ||
212 | /** | |
213 | * cipso_v4_cache_check - Check the CIPSO cache for a label mapping | |
214 | * @key: the buffer to check | |
215 | * @key_len: buffer length in bytes | |
216 | * @secattr: the security attribute struct to use | |
217 | * | |
218 | * Description: | |
219 | * This function checks the cache to see if a label mapping already exists for | |
220 | * the given key. If there is a match then the cache is adjusted and the | |
221 | * @secattr struct is populated with the correct LSM security attributes. The | |
222 | * cache is adjusted in the following manner if the entry is not already the | |
223 | * first in the cache bucket: | |
224 | * | |
225 | * 1. The cache entry's activity counter is incremented | |
226 | * 2. The previous (higher ranking) entry's activity counter is decremented | |
227 | * 3. If the difference between the two activity counters is geater than | |
228 | * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped | |
229 | * | |
230 | * Returns zero on success, -ENOENT for a cache miss, and other negative values | |
231 | * on error. | |
232 | * | |
233 | */ | |
234 | static int cipso_v4_cache_check(const unsigned char *key, | |
235 | u32 key_len, | |
236 | struct netlbl_lsm_secattr *secattr) | |
237 | { | |
238 | u32 bkt; | |
239 | struct cipso_v4_map_cache_entry *entry; | |
240 | struct cipso_v4_map_cache_entry *prev_entry = NULL; | |
241 | u32 hash; | |
242 | ||
243 | if (!cipso_v4_cache_enabled) | |
244 | return -ENOENT; | |
245 | ||
246 | hash = cipso_v4_map_cache_hash(key, key_len); | |
5e0f8923 | 247 | bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 248 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
249 | list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) { |
250 | if (entry->hash == hash && | |
251 | entry->key_len == key_len && | |
252 | memcmp(entry->key, key, key_len) == 0) { | |
253 | entry->activity += 1; | |
b4217b82 | 254 | refcount_inc(&entry->lsm_data->refcount); |
ffb733c6 | 255 | secattr->cache = entry->lsm_data; |
701a90ba | 256 | secattr->flags |= NETLBL_SECATTR_CACHE; |
16efd454 | 257 | secattr->type = NETLBL_NLTYPE_CIPSOV4; |
51456b29 | 258 | if (!prev_entry) { |
609c92fe | 259 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
260 | return 0; |
261 | } | |
262 | ||
263 | if (prev_entry->activity > 0) | |
264 | prev_entry->activity -= 1; | |
265 | if (entry->activity > prev_entry->activity && | |
266 | entry->activity - prev_entry->activity > | |
267 | CIPSO_V4_CACHE_REORDERLIMIT) { | |
268 | __list_del(entry->list.prev, entry->list.next); | |
269 | __list_add(&entry->list, | |
270 | prev_entry->list.prev, | |
271 | &prev_entry->list); | |
272 | } | |
273 | ||
609c92fe | 274 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
275 | return 0; |
276 | } | |
277 | prev_entry = entry; | |
278 | } | |
609c92fe | 279 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
280 | |
281 | return -ENOENT; | |
282 | } | |
283 | ||
284 | /** | |
285 | * cipso_v4_cache_add - Add an entry to the CIPSO cache | |
286 | * @skb: the packet | |
287 | * @secattr: the packet's security attributes | |
288 | * | |
289 | * Description: | |
290 | * Add a new entry into the CIPSO label mapping cache. Add the new entry to | |
291 | * head of the cache bucket's list, if the cache bucket is out of room remove | |
292 | * the last entry in the list first. It is important to note that there is | |
293 | * currently no checking for duplicate keys. Returns zero on success, | |
294 | * negative values on failure. | |
295 | * | |
296 | */ | |
04f81f01 | 297 | int cipso_v4_cache_add(const unsigned char *cipso_ptr, |
446fda4f PM |
298 | const struct netlbl_lsm_secattr *secattr) |
299 | { | |
300 | int ret_val = -EPERM; | |
301 | u32 bkt; | |
302 | struct cipso_v4_map_cache_entry *entry = NULL; | |
303 | struct cipso_v4_map_cache_entry *old_entry = NULL; | |
446fda4f PM |
304 | u32 cipso_ptr_len; |
305 | ||
306 | if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) | |
307 | return 0; | |
308 | ||
446fda4f PM |
309 | cipso_ptr_len = cipso_ptr[1]; |
310 | ||
311 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); | |
51456b29 | 312 | if (!entry) |
446fda4f | 313 | return -ENOMEM; |
fac5d731 | 314 | entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC); |
51456b29 | 315 | if (!entry->key) { |
446fda4f PM |
316 | ret_val = -ENOMEM; |
317 | goto cache_add_failure; | |
318 | } | |
446fda4f PM |
319 | entry->key_len = cipso_ptr_len; |
320 | entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len); | |
b4217b82 | 321 | refcount_inc(&secattr->cache->refcount); |
ffb733c6 | 322 | entry->lsm_data = secattr->cache; |
446fda4f | 323 | |
5e0f8923 | 324 | bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1); |
609c92fe | 325 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
326 | if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { |
327 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
328 | cipso_v4_cache[bkt].size += 1; | |
329 | } else { | |
330 | old_entry = list_entry(cipso_v4_cache[bkt].list.prev, | |
331 | struct cipso_v4_map_cache_entry, list); | |
332 | list_del(&old_entry->list); | |
333 | list_add(&entry->list, &cipso_v4_cache[bkt].list); | |
334 | cipso_v4_cache_entry_free(old_entry); | |
335 | } | |
609c92fe | 336 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
446fda4f PM |
337 | |
338 | return 0; | |
339 | ||
340 | cache_add_failure: | |
341 | if (entry) | |
342 | cipso_v4_cache_entry_free(entry); | |
343 | return ret_val; | |
344 | } | |
345 | ||
346 | /* | |
347 | * DOI List Functions | |
348 | */ | |
349 | ||
350 | /** | |
351 | * cipso_v4_doi_search - Searches for a DOI definition | |
352 | * @doi: the DOI to search for | |
353 | * | |
354 | * Description: | |
355 | * Search the DOI definition list for a DOI definition with a DOI value that | |
25985edc | 356 | * matches @doi. The caller is responsible for calling rcu_read_[un]lock(). |
446fda4f PM |
357 | * Returns a pointer to the DOI definition on success and NULL on failure. |
358 | */ | |
359 | static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) | |
360 | { | |
361 | struct cipso_v4_doi *iter; | |
362 | ||
363 | list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) | |
f6a6fede | 364 | if (iter->doi == doi && refcount_read(&iter->refcount)) |
446fda4f PM |
365 | return iter; |
366 | return NULL; | |
367 | } | |
368 | ||
369 | /** | |
370 | * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine | |
371 | * @doi_def: the DOI structure | |
6c2e8ac0 | 372 | * @audit_info: NetLabel audit information |
446fda4f PM |
373 | * |
374 | * Description: | |
375 | * The caller defines a new DOI for use by the CIPSO engine and calls this | |
376 | * function to add it to the list of acceptable domains. The caller must | |
377 | * ensure that the mapping table specified in @doi_def->map meets all of the | |
378 | * requirements of the mapping type (see cipso_ipv4.h for details). Returns | |
379 | * zero on success and non-zero on failure. | |
380 | * | |
381 | */ | |
6c2e8ac0 PM |
382 | int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, |
383 | struct netlbl_audit *audit_info) | |
446fda4f | 384 | { |
6c2e8ac0 | 385 | int ret_val = -EINVAL; |
6ce61a7c | 386 | u32 iter; |
6c2e8ac0 PM |
387 | u32 doi; |
388 | u32 doi_type; | |
389 | struct audit_buffer *audit_buf; | |
390 | ||
391 | doi = doi_def->doi; | |
392 | doi_type = doi_def->type; | |
6ce61a7c | 393 | |
56755924 | 394 | if (doi_def->doi == CIPSO_V4_DOI_UNKNOWN) |
6c2e8ac0 | 395 | goto doi_add_return; |
6ce61a7c PM |
396 | for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) { |
397 | switch (doi_def->tags[iter]) { | |
398 | case CIPSO_V4_TAG_RBITMAP: | |
399 | break; | |
484b3669 | 400 | case CIPSO_V4_TAG_RANGE: |
654bbc2a PM |
401 | case CIPSO_V4_TAG_ENUM: |
402 | if (doi_def->type != CIPSO_V4_MAP_PASS) | |
6c2e8ac0 | 403 | goto doi_add_return; |
654bbc2a | 404 | break; |
15c45f7b PM |
405 | case CIPSO_V4_TAG_LOCAL: |
406 | if (doi_def->type != CIPSO_V4_MAP_LOCAL) | |
6c2e8ac0 PM |
407 | goto doi_add_return; |
408 | break; | |
409 | case CIPSO_V4_TAG_INVALID: | |
410 | if (iter == 0) | |
411 | goto doi_add_return; | |
15c45f7b | 412 | break; |
6ce61a7c | 413 | default: |
6c2e8ac0 | 414 | goto doi_add_return; |
6ce61a7c PM |
415 | } |
416 | } | |
446fda4f | 417 | |
f6a6fede | 418 | refcount_set(&doi_def->refcount, 1); |
446fda4f | 419 | |
446fda4f | 420 | spin_lock(&cipso_v4_doi_list_lock); |
00db4124 | 421 | if (cipso_v4_doi_search(doi_def->doi)) { |
6c2e8ac0 PM |
422 | spin_unlock(&cipso_v4_doi_list_lock); |
423 | ret_val = -EEXIST; | |
424 | goto doi_add_return; | |
425 | } | |
446fda4f PM |
426 | list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list); |
427 | spin_unlock(&cipso_v4_doi_list_lock); | |
6c2e8ac0 PM |
428 | ret_val = 0; |
429 | ||
430 | doi_add_return: | |
431 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info); | |
00db4124 | 432 | if (audit_buf) { |
6c2e8ac0 PM |
433 | const char *type_str; |
434 | switch (doi_type) { | |
435 | case CIPSO_V4_MAP_TRANS: | |
436 | type_str = "trans"; | |
437 | break; | |
438 | case CIPSO_V4_MAP_PASS: | |
439 | type_str = "pass"; | |
440 | break; | |
441 | case CIPSO_V4_MAP_LOCAL: | |
442 | type_str = "local"; | |
443 | break; | |
444 | default: | |
445 | type_str = "(unknown)"; | |
446 | } | |
447 | audit_log_format(audit_buf, | |
448 | " cipso_doi=%u cipso_type=%s res=%u", | |
449 | doi, type_str, ret_val == 0 ? 1 : 0); | |
450 | audit_log_end(audit_buf); | |
451 | } | |
446fda4f | 452 | |
6c2e8ac0 | 453 | return ret_val; |
446fda4f PM |
454 | } |
455 | ||
b1edeb10 PM |
456 | /** |
457 | * cipso_v4_doi_free - Frees a DOI definition | |
4973404f | 458 | * @doi_def: the DOI definition |
b1edeb10 PM |
459 | * |
460 | * Description: | |
461 | * This function frees all of the memory associated with a DOI definition. | |
462 | * | |
463 | */ | |
464 | void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) | |
465 | { | |
51456b29 | 466 | if (!doi_def) |
b1edeb10 PM |
467 | return; |
468 | ||
469 | switch (doi_def->type) { | |
15c45f7b | 470 | case CIPSO_V4_MAP_TRANS: |
b1edeb10 PM |
471 | kfree(doi_def->map.std->lvl.cipso); |
472 | kfree(doi_def->map.std->lvl.local); | |
473 | kfree(doi_def->map.std->cat.cipso); | |
474 | kfree(doi_def->map.std->cat.local); | |
475 | break; | |
476 | } | |
477 | kfree(doi_def); | |
478 | } | |
479 | ||
480 | /** | |
481 | * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer | |
482 | * @entry: the entry's RCU field | |
483 | * | |
484 | * Description: | |
485 | * This function is designed to be used as a callback to the call_rcu() | |
486 | * function so that the memory allocated to the DOI definition can be released | |
487 | * safely. | |
488 | * | |
489 | */ | |
490 | static void cipso_v4_doi_free_rcu(struct rcu_head *entry) | |
491 | { | |
492 | struct cipso_v4_doi *doi_def; | |
493 | ||
494 | doi_def = container_of(entry, struct cipso_v4_doi, rcu); | |
495 | cipso_v4_doi_free(doi_def); | |
496 | } | |
497 | ||
446fda4f PM |
498 | /** |
499 | * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine | |
500 | * @doi: the DOI value | |
32f50cde | 501 | * @audit_secid: the LSM secid to use in the audit message |
446fda4f PM |
502 | * |
503 | * Description: | |
b1edeb10 PM |
504 | * Removes a DOI definition from the CIPSO engine. The NetLabel routines will |
505 | * be called to release their own LSM domain mappings as well as our own | |
506 | * domain list. Returns zero on success and negative values on failure. | |
446fda4f PM |
507 | * |
508 | */ | |
b1edeb10 | 509 | int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info) |
446fda4f | 510 | { |
6c2e8ac0 | 511 | int ret_val; |
446fda4f | 512 | struct cipso_v4_doi *doi_def; |
6c2e8ac0 | 513 | struct audit_buffer *audit_buf; |
446fda4f | 514 | |
4be2700f PM |
515 | spin_lock(&cipso_v4_doi_list_lock); |
516 | doi_def = cipso_v4_doi_search(doi); | |
51456b29 | 517 | if (!doi_def) { |
446fda4f | 518 | spin_unlock(&cipso_v4_doi_list_lock); |
6c2e8ac0 PM |
519 | ret_val = -ENOENT; |
520 | goto doi_remove_return; | |
446fda4f | 521 | } |
f6a6fede | 522 | if (!refcount_dec_and_test(&doi_def->refcount)) { |
b1edeb10 | 523 | spin_unlock(&cipso_v4_doi_list_lock); |
6c2e8ac0 PM |
524 | ret_val = -EBUSY; |
525 | goto doi_remove_return; | |
b1edeb10 PM |
526 | } |
527 | list_del_rcu(&doi_def->list); | |
4be2700f | 528 | spin_unlock(&cipso_v4_doi_list_lock); |
446fda4f | 529 | |
b1edeb10 PM |
530 | cipso_v4_cache_invalidate(); |
531 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
6c2e8ac0 PM |
532 | ret_val = 0; |
533 | ||
534 | doi_remove_return: | |
535 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info); | |
00db4124 | 536 | if (audit_buf) { |
6c2e8ac0 PM |
537 | audit_log_format(audit_buf, |
538 | " cipso_doi=%u res=%u", | |
539 | doi, ret_val == 0 ? 1 : 0); | |
540 | audit_log_end(audit_buf); | |
541 | } | |
b1edeb10 | 542 | |
6c2e8ac0 | 543 | return ret_val; |
446fda4f PM |
544 | } |
545 | ||
546 | /** | |
b1edeb10 | 547 | * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition |
446fda4f PM |
548 | * @doi: the DOI value |
549 | * | |
550 | * Description: | |
551 | * Searches for a valid DOI definition and if one is found it is returned to | |
552 | * the caller. Otherwise NULL is returned. The caller must ensure that | |
b1edeb10 PM |
553 | * rcu_read_lock() is held while accessing the returned definition and the DOI |
554 | * definition reference count is decremented when the caller is done. | |
446fda4f PM |
555 | * |
556 | */ | |
557 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) | |
558 | { | |
b1edeb10 PM |
559 | struct cipso_v4_doi *doi_def; |
560 | ||
561 | rcu_read_lock(); | |
562 | doi_def = cipso_v4_doi_search(doi); | |
51456b29 | 563 | if (!doi_def) |
b1edeb10 | 564 | goto doi_getdef_return; |
f6a6fede | 565 | if (!refcount_inc_not_zero(&doi_def->refcount)) |
b1edeb10 PM |
566 | doi_def = NULL; |
567 | ||
568 | doi_getdef_return: | |
569 | rcu_read_unlock(); | |
570 | return doi_def; | |
571 | } | |
572 | ||
573 | /** | |
574 | * cipso_v4_doi_putdef - Releases a reference for the given DOI definition | |
575 | * @doi_def: the DOI definition | |
576 | * | |
577 | * Description: | |
578 | * Releases a DOI definition reference obtained from cipso_v4_doi_getdef(). | |
579 | * | |
580 | */ | |
581 | void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) | |
582 | { | |
51456b29 | 583 | if (!doi_def) |
b1edeb10 PM |
584 | return; |
585 | ||
f6a6fede | 586 | if (!refcount_dec_and_test(&doi_def->refcount)) |
b1edeb10 PM |
587 | return; |
588 | spin_lock(&cipso_v4_doi_list_lock); | |
589 | list_del_rcu(&doi_def->list); | |
590 | spin_unlock(&cipso_v4_doi_list_lock); | |
591 | ||
592 | cipso_v4_cache_invalidate(); | |
593 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
446fda4f PM |
594 | } |
595 | ||
596 | /** | |
fcd48280 PM |
597 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
598 | * @skip_cnt: skip past this number of DOI definitions, updated | |
599 | * @callback: callback for each DOI definition | |
600 | * @cb_arg: argument for the callback function | |
446fda4f PM |
601 | * |
602 | * Description: | |
fcd48280 PM |
603 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
604 | * For each entry call @callback, if @callback returns a negative value stop | |
605 | * 'walking' through the list and return. Updates the value in @skip_cnt upon | |
606 | * return. Returns zero on success, negative values on failure. | |
446fda4f PM |
607 | * |
608 | */ | |
fcd48280 PM |
609 | int cipso_v4_doi_walk(u32 *skip_cnt, |
610 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), | |
611 | void *cb_arg) | |
446fda4f | 612 | { |
fcd48280 | 613 | int ret_val = -ENOENT; |
446fda4f | 614 | u32 doi_cnt = 0; |
fcd48280 | 615 | struct cipso_v4_doi *iter_doi; |
446fda4f | 616 | |
446fda4f | 617 | rcu_read_lock(); |
fcd48280 | 618 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
f6a6fede | 619 | if (refcount_read(&iter_doi->refcount) > 0) { |
fcd48280 PM |
620 | if (doi_cnt++ < *skip_cnt) |
621 | continue; | |
622 | ret_val = callback(iter_doi, cb_arg); | |
623 | if (ret_val < 0) { | |
624 | doi_cnt--; | |
625 | goto doi_walk_return; | |
446fda4f | 626 | } |
446fda4f | 627 | } |
446fda4f | 628 | |
fcd48280 | 629 | doi_walk_return: |
446fda4f | 630 | rcu_read_unlock(); |
fcd48280 PM |
631 | *skip_cnt = doi_cnt; |
632 | return ret_val; | |
446fda4f PM |
633 | } |
634 | ||
446fda4f PM |
635 | /* |
636 | * Label Mapping Functions | |
637 | */ | |
638 | ||
639 | /** | |
640 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood | |
641 | * @doi_def: the DOI definition | |
642 | * @level: the level to check | |
643 | * | |
644 | * Description: | |
645 | * Checks the given level against the given DOI definition and returns a | |
646 | * negative value if the level does not have a valid mapping and a zero value | |
647 | * if the level is defined by the DOI. | |
648 | * | |
649 | */ | |
650 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) | |
651 | { | |
652 | switch (doi_def->type) { | |
653 | case CIPSO_V4_MAP_PASS: | |
654 | return 0; | |
15c45f7b | 655 | case CIPSO_V4_MAP_TRANS: |
5578de48 PM |
656 | if ((level < doi_def->map.std->lvl.cipso_size) && |
657 | (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)) | |
446fda4f PM |
658 | return 0; |
659 | break; | |
660 | } | |
661 | ||
662 | return -EFAULT; | |
663 | } | |
664 | ||
665 | /** | |
666 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network | |
667 | * @doi_def: the DOI definition | |
668 | * @host_lvl: the host MLS level | |
669 | * @net_lvl: the network/CIPSO MLS level | |
670 | * | |
671 | * Description: | |
672 | * Perform a label mapping to translate a local MLS level to the correct | |
673 | * CIPSO level using the given DOI definition. Returns zero on success, | |
674 | * negative values otherwise. | |
675 | * | |
676 | */ | |
677 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, | |
678 | u32 host_lvl, | |
679 | u32 *net_lvl) | |
680 | { | |
681 | switch (doi_def->type) { | |
682 | case CIPSO_V4_MAP_PASS: | |
683 | *net_lvl = host_lvl; | |
684 | return 0; | |
15c45f7b | 685 | case CIPSO_V4_MAP_TRANS: |
c6387a86 PM |
686 | if (host_lvl < doi_def->map.std->lvl.local_size && |
687 | doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) { | |
446fda4f PM |
688 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
689 | return 0; | |
690 | } | |
c6387a86 | 691 | return -EPERM; |
446fda4f PM |
692 | } |
693 | ||
694 | return -EINVAL; | |
695 | } | |
696 | ||
697 | /** | |
698 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host | |
699 | * @doi_def: the DOI definition | |
700 | * @net_lvl: the network/CIPSO MLS level | |
701 | * @host_lvl: the host MLS level | |
702 | * | |
703 | * Description: | |
704 | * Perform a label mapping to translate a CIPSO level to the correct local MLS | |
705 | * level using the given DOI definition. Returns zero on success, negative | |
706 | * values otherwise. | |
707 | * | |
708 | */ | |
709 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, | |
710 | u32 net_lvl, | |
711 | u32 *host_lvl) | |
712 | { | |
713 | struct cipso_v4_std_map_tbl *map_tbl; | |
714 | ||
715 | switch (doi_def->type) { | |
716 | case CIPSO_V4_MAP_PASS: | |
717 | *host_lvl = net_lvl; | |
718 | return 0; | |
15c45f7b | 719 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
720 | map_tbl = doi_def->map.std; |
721 | if (net_lvl < map_tbl->lvl.cipso_size && | |
722 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { | |
723 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; | |
724 | return 0; | |
725 | } | |
c6387a86 | 726 | return -EPERM; |
446fda4f PM |
727 | } |
728 | ||
729 | return -EINVAL; | |
730 | } | |
731 | ||
732 | /** | |
733 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid | |
734 | * @doi_def: the DOI definition | |
735 | * @bitmap: category bitmap | |
736 | * @bitmap_len: bitmap length in bytes | |
737 | * | |
738 | * Description: | |
739 | * Checks the given category bitmap against the given DOI definition and | |
740 | * returns a negative value if any of the categories in the bitmap do not have | |
741 | * a valid mapping and a zero value if all of the categories are valid. | |
742 | * | |
743 | */ | |
744 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, | |
745 | const unsigned char *bitmap, | |
746 | u32 bitmap_len) | |
747 | { | |
748 | int cat = -1; | |
749 | u32 bitmap_len_bits = bitmap_len * 8; | |
044a68ed PM |
750 | u32 cipso_cat_size; |
751 | u32 *cipso_array; | |
446fda4f PM |
752 | |
753 | switch (doi_def->type) { | |
754 | case CIPSO_V4_MAP_PASS: | |
755 | return 0; | |
15c45f7b | 756 | case CIPSO_V4_MAP_TRANS: |
044a68ed PM |
757 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
758 | cipso_array = doi_def->map.std->cat.cipso; | |
446fda4f | 759 | for (;;) { |
3faa8f98 HD |
760 | cat = netlbl_bitmap_walk(bitmap, |
761 | bitmap_len_bits, | |
762 | cat + 1, | |
763 | 1); | |
446fda4f PM |
764 | if (cat < 0) |
765 | break; | |
766 | if (cat >= cipso_cat_size || | |
767 | cipso_array[cat] >= CIPSO_V4_INV_CAT) | |
768 | return -EFAULT; | |
769 | } | |
770 | ||
771 | if (cat == -1) | |
772 | return 0; | |
773 | break; | |
774 | } | |
775 | ||
776 | return -EFAULT; | |
777 | } | |
778 | ||
779 | /** | |
780 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network | |
781 | * @doi_def: the DOI definition | |
02752760 | 782 | * @secattr: the security attributes |
446fda4f PM |
783 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
784 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
785 | * | |
786 | * Description: | |
787 | * Perform a label mapping to translate a local MLS category bitmap to the | |
788 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum | |
789 | * size in bytes of the network bitmap on success, negative values otherwise. | |
790 | * | |
791 | */ | |
792 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, | |
02752760 | 793 | const struct netlbl_lsm_secattr *secattr, |
446fda4f PM |
794 | unsigned char *net_cat, |
795 | u32 net_cat_len) | |
796 | { | |
797 | int host_spot = -1; | |
02752760 | 798 | u32 net_spot = CIPSO_V4_INV_CAT; |
446fda4f | 799 | u32 net_spot_max = 0; |
446fda4f | 800 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
801 | u32 host_cat_size = 0; |
802 | u32 *host_cat_array = NULL; | |
446fda4f | 803 | |
15c45f7b | 804 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
805 | host_cat_size = doi_def->map.std->cat.local_size; |
806 | host_cat_array = doi_def->map.std->cat.local; | |
02752760 PM |
807 | } |
808 | ||
809 | for (;;) { | |
4fbe63d1 PM |
810 | host_spot = netlbl_catmap_walk(secattr->attr.mls.cat, |
811 | host_spot + 1); | |
02752760 PM |
812 | if (host_spot < 0) |
813 | break; | |
814 | ||
815 | switch (doi_def->type) { | |
816 | case CIPSO_V4_MAP_PASS: | |
817 | net_spot = host_spot; | |
818 | break; | |
15c45f7b | 819 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
820 | if (host_spot >= host_cat_size) |
821 | return -EPERM; | |
446fda4f | 822 | net_spot = host_cat_array[host_spot]; |
9fade4bf PM |
823 | if (net_spot >= CIPSO_V4_INV_CAT) |
824 | return -EPERM; | |
02752760 | 825 | break; |
446fda4f | 826 | } |
02752760 PM |
827 | if (net_spot >= net_clen_bits) |
828 | return -ENOSPC; | |
3faa8f98 | 829 | netlbl_bitmap_setbit(net_cat, net_spot, 1); |
446fda4f | 830 | |
02752760 PM |
831 | if (net_spot > net_spot_max) |
832 | net_spot_max = net_spot; | |
446fda4f PM |
833 | } |
834 | ||
02752760 PM |
835 | if (++net_spot_max % 8) |
836 | return net_spot_max / 8 + 1; | |
837 | return net_spot_max / 8; | |
446fda4f PM |
838 | } |
839 | ||
840 | /** | |
841 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host | |
842 | * @doi_def: the DOI definition | |
843 | * @net_cat: the category bitmap in network/CIPSO format | |
844 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
02752760 | 845 | * @secattr: the security attributes |
446fda4f PM |
846 | * |
847 | * Description: | |
848 | * Perform a label mapping to translate a CIPSO bitmap to the correct local | |
02752760 PM |
849 | * MLS category bitmap using the given DOI definition. Returns zero on |
850 | * success, negative values on failure. | |
446fda4f PM |
851 | * |
852 | */ | |
853 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, | |
854 | const unsigned char *net_cat, | |
855 | u32 net_cat_len, | |
02752760 | 856 | struct netlbl_lsm_secattr *secattr) |
446fda4f | 857 | { |
02752760 | 858 | int ret_val; |
446fda4f | 859 | int net_spot = -1; |
02752760 | 860 | u32 host_spot = CIPSO_V4_INV_CAT; |
446fda4f | 861 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
862 | u32 net_cat_size = 0; |
863 | u32 *net_cat_array = NULL; | |
446fda4f | 864 | |
15c45f7b | 865 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
866 | net_cat_size = doi_def->map.std->cat.cipso_size; |
867 | net_cat_array = doi_def->map.std->cat.cipso; | |
02752760 | 868 | } |
446fda4f | 869 | |
02752760 | 870 | for (;;) { |
3faa8f98 HD |
871 | net_spot = netlbl_bitmap_walk(net_cat, |
872 | net_clen_bits, | |
873 | net_spot + 1, | |
874 | 1); | |
02752760 PM |
875 | if (net_spot < 0) { |
876 | if (net_spot == -2) | |
877 | return -EFAULT; | |
878 | return 0; | |
879 | } | |
880 | ||
881 | switch (doi_def->type) { | |
882 | case CIPSO_V4_MAP_PASS: | |
883 | host_spot = net_spot; | |
884 | break; | |
15c45f7b | 885 | case CIPSO_V4_MAP_TRANS: |
02752760 PM |
886 | if (net_spot >= net_cat_size) |
887 | return -EPERM; | |
446fda4f | 888 | host_spot = net_cat_array[net_spot]; |
9fade4bf PM |
889 | if (host_spot >= CIPSO_V4_INV_CAT) |
890 | return -EPERM; | |
02752760 | 891 | break; |
446fda4f | 892 | } |
4fbe63d1 | 893 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
02752760 PM |
894 | host_spot, |
895 | GFP_ATOMIC); | |
896 | if (ret_val != 0) | |
897 | return ret_val; | |
446fda4f PM |
898 | } |
899 | ||
900 | return -EINVAL; | |
901 | } | |
902 | ||
654bbc2a PM |
903 | /** |
904 | * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid | |
905 | * @doi_def: the DOI definition | |
906 | * @enumcat: category list | |
907 | * @enumcat_len: length of the category list in bytes | |
908 | * | |
909 | * Description: | |
910 | * Checks the given categories against the given DOI definition and returns a | |
911 | * negative value if any of the categories do not have a valid mapping and a | |
912 | * zero value if all of the categories are valid. | |
913 | * | |
914 | */ | |
915 | static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, | |
916 | const unsigned char *enumcat, | |
917 | u32 enumcat_len) | |
918 | { | |
919 | u16 cat; | |
920 | int cat_prev = -1; | |
921 | u32 iter; | |
922 | ||
923 | if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01) | |
924 | return -EFAULT; | |
925 | ||
926 | for (iter = 0; iter < enumcat_len; iter += 2) { | |
d3e2ce3b | 927 | cat = get_unaligned_be16(&enumcat[iter]); |
654bbc2a PM |
928 | if (cat <= cat_prev) |
929 | return -EFAULT; | |
930 | cat_prev = cat; | |
931 | } | |
932 | ||
933 | return 0; | |
934 | } | |
935 | ||
936 | /** | |
937 | * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network | |
938 | * @doi_def: the DOI definition | |
939 | * @secattr: the security attributes | |
940 | * @net_cat: the zero'd out category list in network/CIPSO format | |
941 | * @net_cat_len: the length of the CIPSO category list in bytes | |
942 | * | |
943 | * Description: | |
944 | * Perform a label mapping to translate a local MLS category bitmap to the | |
945 | * correct CIPSO category list using the given DOI definition. Returns the | |
946 | * size in bytes of the network category bitmap on success, negative values | |
947 | * otherwise. | |
948 | * | |
949 | */ | |
950 | static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, | |
951 | const struct netlbl_lsm_secattr *secattr, | |
952 | unsigned char *net_cat, | |
953 | u32 net_cat_len) | |
954 | { | |
955 | int cat = -1; | |
956 | u32 cat_iter = 0; | |
957 | ||
958 | for (;;) { | |
4fbe63d1 | 959 | cat = netlbl_catmap_walk(secattr->attr.mls.cat, cat + 1); |
654bbc2a PM |
960 | if (cat < 0) |
961 | break; | |
962 | if ((cat_iter + 2) > net_cat_len) | |
963 | return -ENOSPC; | |
964 | ||
965 | *((__be16 *)&net_cat[cat_iter]) = htons(cat); | |
966 | cat_iter += 2; | |
967 | } | |
968 | ||
969 | return cat_iter; | |
970 | } | |
971 | ||
972 | /** | |
973 | * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host | |
974 | * @doi_def: the DOI definition | |
975 | * @net_cat: the category list in network/CIPSO format | |
976 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
977 | * @secattr: the security attributes | |
978 | * | |
979 | * Description: | |
980 | * Perform a label mapping to translate a CIPSO category list to the correct | |
981 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
982 | * success, negative values on failure. | |
983 | * | |
984 | */ | |
985 | static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, | |
986 | const unsigned char *net_cat, | |
987 | u32 net_cat_len, | |
988 | struct netlbl_lsm_secattr *secattr) | |
989 | { | |
990 | int ret_val; | |
991 | u32 iter; | |
992 | ||
993 | for (iter = 0; iter < net_cat_len; iter += 2) { | |
4fbe63d1 PM |
994 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
995 | get_unaligned_be16(&net_cat[iter]), | |
996 | GFP_ATOMIC); | |
654bbc2a PM |
997 | if (ret_val != 0) |
998 | return ret_val; | |
999 | } | |
1000 | ||
1001 | return 0; | |
1002 | } | |
1003 | ||
484b3669 PM |
1004 | /** |
1005 | * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid | |
1006 | * @doi_def: the DOI definition | |
1007 | * @rngcat: category list | |
1008 | * @rngcat_len: length of the category list in bytes | |
1009 | * | |
1010 | * Description: | |
1011 | * Checks the given categories against the given DOI definition and returns a | |
1012 | * negative value if any of the categories do not have a valid mapping and a | |
1013 | * zero value if all of the categories are valid. | |
1014 | * | |
1015 | */ | |
1016 | static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, | |
1017 | const unsigned char *rngcat, | |
1018 | u32 rngcat_len) | |
1019 | { | |
1020 | u16 cat_high; | |
1021 | u16 cat_low; | |
1022 | u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1; | |
1023 | u32 iter; | |
1024 | ||
1025 | if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01) | |
1026 | return -EFAULT; | |
1027 | ||
1028 | for (iter = 0; iter < rngcat_len; iter += 4) { | |
d3e2ce3b | 1029 | cat_high = get_unaligned_be16(&rngcat[iter]); |
484b3669 | 1030 | if ((iter + 4) <= rngcat_len) |
d3e2ce3b | 1031 | cat_low = get_unaligned_be16(&rngcat[iter + 2]); |
484b3669 PM |
1032 | else |
1033 | cat_low = 0; | |
1034 | ||
1035 | if (cat_high > cat_prev) | |
1036 | return -EFAULT; | |
1037 | ||
1038 | cat_prev = cat_low; | |
1039 | } | |
1040 | ||
1041 | return 0; | |
1042 | } | |
1043 | ||
1044 | /** | |
1045 | * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network | |
1046 | * @doi_def: the DOI definition | |
1047 | * @secattr: the security attributes | |
1048 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1049 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1050 | * | |
1051 | * Description: | |
1052 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1053 | * correct CIPSO category list using the given DOI definition. Returns the | |
1054 | * size in bytes of the network category bitmap on success, negative values | |
1055 | * otherwise. | |
1056 | * | |
1057 | */ | |
1058 | static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, | |
1059 | const struct netlbl_lsm_secattr *secattr, | |
1060 | unsigned char *net_cat, | |
1061 | u32 net_cat_len) | |
1062 | { | |
484b3669 | 1063 | int iter = -1; |
f998e8cb | 1064 | u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2]; |
484b3669 PM |
1065 | u32 array_cnt = 0; |
1066 | u32 cat_size = 0; | |
1067 | ||
f998e8cb | 1068 | /* make sure we don't overflow the 'array[]' variable */ |
128c6b6c PM |
1069 | if (net_cat_len > |
1070 | (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN)) | |
1071 | return -ENOSPC; | |
484b3669 PM |
1072 | |
1073 | for (;;) { | |
4fbe63d1 | 1074 | iter = netlbl_catmap_walk(secattr->attr.mls.cat, iter + 1); |
484b3669 PM |
1075 | if (iter < 0) |
1076 | break; | |
1077 | cat_size += (iter == 0 ? 0 : sizeof(u16)); | |
1078 | if (cat_size > net_cat_len) | |
1079 | return -ENOSPC; | |
1080 | array[array_cnt++] = iter; | |
1081 | ||
4fbe63d1 | 1082 | iter = netlbl_catmap_walkrng(secattr->attr.mls.cat, iter); |
484b3669 PM |
1083 | if (iter < 0) |
1084 | return -EFAULT; | |
1085 | cat_size += sizeof(u16); | |
1086 | if (cat_size > net_cat_len) | |
1087 | return -ENOSPC; | |
1088 | array[array_cnt++] = iter; | |
1089 | } | |
1090 | ||
1091 | for (iter = 0; array_cnt > 0;) { | |
1092 | *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]); | |
1093 | iter += 2; | |
1094 | array_cnt--; | |
1095 | if (array[array_cnt] != 0) { | |
1096 | *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]); | |
1097 | iter += 2; | |
1098 | } | |
1099 | } | |
1100 | ||
1101 | return cat_size; | |
1102 | } | |
1103 | ||
1104 | /** | |
1105 | * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host | |
1106 | * @doi_def: the DOI definition | |
1107 | * @net_cat: the category list in network/CIPSO format | |
1108 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1109 | * @secattr: the security attributes | |
1110 | * | |
1111 | * Description: | |
1112 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1113 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1114 | * success, negative values on failure. | |
1115 | * | |
1116 | */ | |
1117 | static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, | |
1118 | const unsigned char *net_cat, | |
1119 | u32 net_cat_len, | |
1120 | struct netlbl_lsm_secattr *secattr) | |
1121 | { | |
1122 | int ret_val; | |
1123 | u32 net_iter; | |
1124 | u16 cat_low; | |
1125 | u16 cat_high; | |
1126 | ||
132adf54 | 1127 | for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) { |
d3e2ce3b | 1128 | cat_high = get_unaligned_be16(&net_cat[net_iter]); |
484b3669 | 1129 | if ((net_iter + 4) <= net_cat_len) |
d3e2ce3b | 1130 | cat_low = get_unaligned_be16(&net_cat[net_iter + 2]); |
484b3669 PM |
1131 | else |
1132 | cat_low = 0; | |
1133 | ||
4fbe63d1 PM |
1134 | ret_val = netlbl_catmap_setrng(&secattr->attr.mls.cat, |
1135 | cat_low, | |
1136 | cat_high, | |
1137 | GFP_ATOMIC); | |
484b3669 PM |
1138 | if (ret_val != 0) |
1139 | return ret_val; | |
1140 | } | |
1141 | ||
1142 | return 0; | |
1143 | } | |
1144 | ||
446fda4f PM |
1145 | /* |
1146 | * Protocol Handling Functions | |
1147 | */ | |
1148 | ||
446fda4f PM |
1149 | /** |
1150 | * cipso_v4_gentag_hdr - Generate a CIPSO option header | |
1151 | * @doi_def: the DOI definition | |
91b1ed0a | 1152 | * @len: the total tag length in bytes, not including this header |
446fda4f PM |
1153 | * @buf: the CIPSO option buffer |
1154 | * | |
1155 | * Description: | |
91b1ed0a | 1156 | * Write a CIPSO header into the beginning of @buffer. |
446fda4f PM |
1157 | * |
1158 | */ | |
91b1ed0a PM |
1159 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
1160 | unsigned char *buf, | |
1161 | u32 len) | |
446fda4f | 1162 | { |
446fda4f PM |
1163 | buf[0] = IPOPT_CIPSO; |
1164 | buf[1] = CIPSO_V4_HDR_LEN + len; | |
714e85be | 1165 | *(__be32 *)&buf[2] = htonl(doi_def->doi); |
446fda4f PM |
1166 | } |
1167 | ||
446fda4f PM |
1168 | /** |
1169 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) | |
1170 | * @doi_def: the DOI definition | |
1171 | * @secattr: the security attributes | |
1172 | * @buffer: the option buffer | |
1173 | * @buffer_len: length of buffer in bytes | |
1174 | * | |
1175 | * Description: | |
1176 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The | |
1177 | * actual buffer length may be larger than the indicated size due to | |
91b1ed0a PM |
1178 | * translation between host and network category bitmaps. Returns the size of |
1179 | * the tag on success, negative values on failure. | |
446fda4f PM |
1180 | * |
1181 | */ | |
1182 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, | |
1183 | const struct netlbl_lsm_secattr *secattr, | |
91b1ed0a PM |
1184 | unsigned char *buffer, |
1185 | u32 buffer_len) | |
446fda4f | 1186 | { |
701a90ba | 1187 | int ret_val; |
91b1ed0a | 1188 | u32 tag_len; |
446fda4f PM |
1189 | u32 level; |
1190 | ||
701a90ba PM |
1191 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
1192 | return -EPERM; | |
1193 | ||
16efd454 PM |
1194 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1195 | secattr->attr.mls.lvl, | |
1196 | &level); | |
91b1ed0a PM |
1197 | if (ret_val != 0) |
1198 | return ret_val; | |
446fda4f | 1199 | |
91b1ed0a | 1200 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
446fda4f | 1201 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
02752760 | 1202 | secattr, |
91b1ed0a PM |
1203 | &buffer[4], |
1204 | buffer_len - 4); | |
446fda4f | 1205 | if (ret_val < 0) |
91b1ed0a | 1206 | return ret_val; |
446fda4f PM |
1207 | |
1208 | /* This will send packets using the "optimized" format when | |
25985edc | 1209 | * possible as specified in section 3.4.2.6 of the |
446fda4f | 1210 | * CIPSO draft. */ |
701a90ba | 1211 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
91b1ed0a | 1212 | tag_len = 14; |
701a90ba | 1213 | else |
91b1ed0a PM |
1214 | tag_len = 4 + ret_val; |
1215 | } else | |
1216 | tag_len = 4; | |
446fda4f | 1217 | |
15c45f7b | 1218 | buffer[0] = CIPSO_V4_TAG_RBITMAP; |
91b1ed0a PM |
1219 | buffer[1] = tag_len; |
1220 | buffer[3] = level; | |
446fda4f | 1221 | |
91b1ed0a | 1222 | return tag_len; |
446fda4f PM |
1223 | } |
1224 | ||
1225 | /** | |
1226 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag | |
1227 | * @doi_def: the DOI definition | |
1228 | * @tag: the CIPSO tag | |
1229 | * @secattr: the security attributes | |
1230 | * | |
1231 | * Description: | |
1232 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security | |
1233 | * attributes in @secattr. Return zero on success, negatives values on | |
1234 | * failure. | |
1235 | * | |
1236 | */ | |
1237 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, | |
1238 | const unsigned char *tag, | |
1239 | struct netlbl_lsm_secattr *secattr) | |
1240 | { | |
1241 | int ret_val; | |
1242 | u8 tag_len = tag[1]; | |
1243 | u32 level; | |
1244 | ||
1245 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1246 | if (ret_val != 0) | |
1247 | return ret_val; | |
16efd454 | 1248 | secattr->attr.mls.lvl = level; |
701a90ba | 1249 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
446fda4f PM |
1250 | |
1251 | if (tag_len > 4) { | |
446fda4f PM |
1252 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, |
1253 | &tag[4], | |
1254 | tag_len - 4, | |
02752760 PM |
1255 | secattr); |
1256 | if (ret_val != 0) { | |
4fbe63d1 | 1257 | netlbl_catmap_free(secattr->attr.mls.cat); |
446fda4f PM |
1258 | return ret_val; |
1259 | } | |
02752760 | 1260 | |
eead1c2e PA |
1261 | if (secattr->attr.mls.cat) |
1262 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
446fda4f PM |
1263 | } |
1264 | ||
1265 | return 0; | |
1266 | } | |
1267 | ||
654bbc2a PM |
1268 | /** |
1269 | * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) | |
1270 | * @doi_def: the DOI definition | |
1271 | * @secattr: the security attributes | |
1272 | * @buffer: the option buffer | |
1273 | * @buffer_len: length of buffer in bytes | |
1274 | * | |
1275 | * Description: | |
1276 | * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the | |
1277 | * size of the tag on success, negative values on failure. | |
1278 | * | |
1279 | */ | |
1280 | static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, | |
1281 | const struct netlbl_lsm_secattr *secattr, | |
1282 | unsigned char *buffer, | |
1283 | u32 buffer_len) | |
1284 | { | |
1285 | int ret_val; | |
1286 | u32 tag_len; | |
1287 | u32 level; | |
1288 | ||
1289 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1290 | return -EPERM; | |
1291 | ||
16efd454 PM |
1292 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1293 | secattr->attr.mls.lvl, | |
1294 | &level); | |
654bbc2a PM |
1295 | if (ret_val != 0) |
1296 | return ret_val; | |
1297 | ||
1298 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1299 | ret_val = cipso_v4_map_cat_enum_hton(doi_def, | |
1300 | secattr, | |
1301 | &buffer[4], | |
1302 | buffer_len - 4); | |
1303 | if (ret_val < 0) | |
1304 | return ret_val; | |
1305 | ||
1306 | tag_len = 4 + ret_val; | |
1307 | } else | |
1308 | tag_len = 4; | |
1309 | ||
15c45f7b | 1310 | buffer[0] = CIPSO_V4_TAG_ENUM; |
654bbc2a PM |
1311 | buffer[1] = tag_len; |
1312 | buffer[3] = level; | |
1313 | ||
1314 | return tag_len; | |
1315 | } | |
1316 | ||
1317 | /** | |
1318 | * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag | |
1319 | * @doi_def: the DOI definition | |
1320 | * @tag: the CIPSO tag | |
1321 | * @secattr: the security attributes | |
1322 | * | |
1323 | * Description: | |
1324 | * Parse a CIPSO enumerated tag (tag type #2) and return the security | |
1325 | * attributes in @secattr. Return zero on success, negatives values on | |
1326 | * failure. | |
1327 | * | |
1328 | */ | |
1329 | static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, | |
1330 | const unsigned char *tag, | |
1331 | struct netlbl_lsm_secattr *secattr) | |
1332 | { | |
1333 | int ret_val; | |
1334 | u8 tag_len = tag[1]; | |
1335 | u32 level; | |
1336 | ||
1337 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1338 | if (ret_val != 0) | |
1339 | return ret_val; | |
16efd454 | 1340 | secattr->attr.mls.lvl = level; |
654bbc2a PM |
1341 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1342 | ||
1343 | if (tag_len > 4) { | |
654bbc2a PM |
1344 | ret_val = cipso_v4_map_cat_enum_ntoh(doi_def, |
1345 | &tag[4], | |
1346 | tag_len - 4, | |
1347 | secattr); | |
1348 | if (ret_val != 0) { | |
4fbe63d1 | 1349 | netlbl_catmap_free(secattr->attr.mls.cat); |
654bbc2a PM |
1350 | return ret_val; |
1351 | } | |
1352 | ||
1353 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1354 | } | |
1355 | ||
1356 | return 0; | |
1357 | } | |
1358 | ||
484b3669 PM |
1359 | /** |
1360 | * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) | |
1361 | * @doi_def: the DOI definition | |
1362 | * @secattr: the security attributes | |
1363 | * @buffer: the option buffer | |
1364 | * @buffer_len: length of buffer in bytes | |
1365 | * | |
1366 | * Description: | |
1367 | * Generate a CIPSO option using the ranged tag, tag type #5. Returns the | |
1368 | * size of the tag on success, negative values on failure. | |
1369 | * | |
1370 | */ | |
1371 | static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, | |
1372 | const struct netlbl_lsm_secattr *secattr, | |
1373 | unsigned char *buffer, | |
1374 | u32 buffer_len) | |
1375 | { | |
1376 | int ret_val; | |
1377 | u32 tag_len; | |
1378 | u32 level; | |
1379 | ||
1380 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1381 | return -EPERM; | |
1382 | ||
16efd454 PM |
1383 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1384 | secattr->attr.mls.lvl, | |
1385 | &level); | |
484b3669 PM |
1386 | if (ret_val != 0) |
1387 | return ret_val; | |
1388 | ||
1389 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1390 | ret_val = cipso_v4_map_cat_rng_hton(doi_def, | |
1391 | secattr, | |
1392 | &buffer[4], | |
1393 | buffer_len - 4); | |
1394 | if (ret_val < 0) | |
1395 | return ret_val; | |
1396 | ||
1397 | tag_len = 4 + ret_val; | |
1398 | } else | |
1399 | tag_len = 4; | |
1400 | ||
15c45f7b | 1401 | buffer[0] = CIPSO_V4_TAG_RANGE; |
484b3669 PM |
1402 | buffer[1] = tag_len; |
1403 | buffer[3] = level; | |
1404 | ||
1405 | return tag_len; | |
1406 | } | |
1407 | ||
1408 | /** | |
1409 | * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag | |
1410 | * @doi_def: the DOI definition | |
1411 | * @tag: the CIPSO tag | |
1412 | * @secattr: the security attributes | |
1413 | * | |
1414 | * Description: | |
1415 | * Parse a CIPSO ranged tag (tag type #5) and return the security attributes | |
1416 | * in @secattr. Return zero on success, negatives values on failure. | |
1417 | * | |
1418 | */ | |
1419 | static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, | |
1420 | const unsigned char *tag, | |
1421 | struct netlbl_lsm_secattr *secattr) | |
1422 | { | |
1423 | int ret_val; | |
1424 | u8 tag_len = tag[1]; | |
1425 | u32 level; | |
1426 | ||
1427 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1428 | if (ret_val != 0) | |
1429 | return ret_val; | |
16efd454 | 1430 | secattr->attr.mls.lvl = level; |
484b3669 PM |
1431 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1432 | ||
1433 | if (tag_len > 4) { | |
484b3669 PM |
1434 | ret_val = cipso_v4_map_cat_rng_ntoh(doi_def, |
1435 | &tag[4], | |
1436 | tag_len - 4, | |
1437 | secattr); | |
1438 | if (ret_val != 0) { | |
4fbe63d1 | 1439 | netlbl_catmap_free(secattr->attr.mls.cat); |
484b3669 PM |
1440 | return ret_val; |
1441 | } | |
1442 | ||
eead1c2e PA |
1443 | if (secattr->attr.mls.cat) |
1444 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
484b3669 PM |
1445 | } |
1446 | ||
1447 | return 0; | |
1448 | } | |
1449 | ||
15c45f7b PM |
1450 | /** |
1451 | * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard) | |
1452 | * @doi_def: the DOI definition | |
1453 | * @secattr: the security attributes | |
1454 | * @buffer: the option buffer | |
1455 | * @buffer_len: length of buffer in bytes | |
1456 | * | |
1457 | * Description: | |
1458 | * Generate a CIPSO option using the local tag. Returns the size of the tag | |
1459 | * on success, negative values on failure. | |
1460 | * | |
1461 | */ | |
1462 | static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def, | |
1463 | const struct netlbl_lsm_secattr *secattr, | |
1464 | unsigned char *buffer, | |
1465 | u32 buffer_len) | |
1466 | { | |
1467 | if (!(secattr->flags & NETLBL_SECATTR_SECID)) | |
1468 | return -EPERM; | |
1469 | ||
1470 | buffer[0] = CIPSO_V4_TAG_LOCAL; | |
1471 | buffer[1] = CIPSO_V4_TAG_LOC_BLEN; | |
1472 | *(u32 *)&buffer[2] = secattr->attr.secid; | |
1473 | ||
1474 | return CIPSO_V4_TAG_LOC_BLEN; | |
1475 | } | |
1476 | ||
1477 | /** | |
1478 | * cipso_v4_parsetag_loc - Parse a CIPSO local tag | |
1479 | * @doi_def: the DOI definition | |
1480 | * @tag: the CIPSO tag | |
1481 | * @secattr: the security attributes | |
1482 | * | |
1483 | * Description: | |
1484 | * Parse a CIPSO local tag and return the security attributes in @secattr. | |
1485 | * Return zero on success, negatives values on failure. | |
1486 | * | |
1487 | */ | |
1488 | static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def, | |
1489 | const unsigned char *tag, | |
1490 | struct netlbl_lsm_secattr *secattr) | |
1491 | { | |
1492 | secattr->attr.secid = *(u32 *)&tag[2]; | |
1493 | secattr->flags |= NETLBL_SECATTR_SECID; | |
1494 | ||
1495 | return 0; | |
1496 | } | |
1497 | ||
04f81f01 PM |
1498 | /** |
1499 | * cipso_v4_optptr - Find the CIPSO option in the packet | |
1500 | * @skb: the packet | |
1501 | * | |
1502 | * Description: | |
1503 | * Parse the packet's IP header looking for a CIPSO option. Returns a pointer | |
076ed3da | 1504 | * to the start of the CIPSO option on success, NULL if one is not found. |
04f81f01 PM |
1505 | * |
1506 | */ | |
1507 | unsigned char *cipso_v4_optptr(const struct sk_buff *skb) | |
1508 | { | |
1509 | const struct iphdr *iph = ip_hdr(skb); | |
1510 | unsigned char *optptr = (unsigned char *)&(ip_hdr(skb)[1]); | |
1511 | int optlen; | |
1512 | int taglen; | |
1513 | ||
076ed3da | 1514 | for (optlen = iph->ihl*4 - sizeof(struct iphdr); optlen > 1; ) { |
40413955 | 1515 | switch (optptr[0]) { |
40413955 | 1516 | case IPOPT_END: |
1517 | return NULL; | |
1518 | case IPOPT_NOOP: | |
1519 | taglen = 1; | |
1520 | break; | |
1521 | default: | |
1522 | taglen = optptr[1]; | |
1523 | } | |
076ed3da SN |
1524 | if (!taglen || taglen > optlen) |
1525 | return NULL; | |
1526 | if (optptr[0] == IPOPT_CIPSO) | |
1527 | return optptr; | |
1528 | ||
04f81f01 PM |
1529 | optlen -= taglen; |
1530 | optptr += taglen; | |
1531 | } | |
1532 | ||
1533 | return NULL; | |
1534 | } | |
1535 | ||
446fda4f PM |
1536 | /** |
1537 | * cipso_v4_validate - Validate a CIPSO option | |
1538 | * @option: the start of the option, on error it is set to point to the error | |
1539 | * | |
1540 | * Description: | |
1541 | * This routine is called to validate a CIPSO option, it checks all of the | |
1542 | * fields to ensure that they are at least valid, see the draft snippet below | |
1543 | * for details. If the option is valid then a zero value is returned and | |
1544 | * the value of @option is unchanged. If the option is invalid then a | |
1545 | * non-zero value is returned and @option is adjusted to point to the | |
1546 | * offending portion of the option. From the IETF draft ... | |
1547 | * | |
1548 | * "If any field within the CIPSO options, such as the DOI identifier, is not | |
1549 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' | |
1550 | * (type 12) is generated and returned. The ICMP code field is set to 'bad | |
1551 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field | |
1552 | * that is unrecognized." | |
1553 | * | |
1554 | */ | |
15c45f7b | 1555 | int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) |
446fda4f PM |
1556 | { |
1557 | unsigned char *opt = *option; | |
1558 | unsigned char *tag; | |
1559 | unsigned char opt_iter; | |
1560 | unsigned char err_offset = 0; | |
1561 | u8 opt_len; | |
1562 | u8 tag_len; | |
1563 | struct cipso_v4_doi *doi_def = NULL; | |
1564 | u32 tag_iter; | |
1565 | ||
1566 | /* caller already checks for length values that are too large */ | |
1567 | opt_len = opt[1]; | |
1568 | if (opt_len < 8) { | |
1569 | err_offset = 1; | |
1570 | goto validate_return; | |
1571 | } | |
1572 | ||
1573 | rcu_read_lock(); | |
d3e2ce3b | 1574 | doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2])); |
51456b29 | 1575 | if (!doi_def) { |
446fda4f PM |
1576 | err_offset = 2; |
1577 | goto validate_return_locked; | |
1578 | } | |
1579 | ||
15c45f7b | 1580 | opt_iter = CIPSO_V4_HDR_LEN; |
446fda4f PM |
1581 | tag = opt + opt_iter; |
1582 | while (opt_iter < opt_len) { | |
1583 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) | |
1584 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || | |
1585 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { | |
1586 | err_offset = opt_iter; | |
1587 | goto validate_return_locked; | |
1588 | } | |
1589 | ||
d71b7896 ED |
1590 | if (opt_iter + 1 == opt_len) { |
1591 | err_offset = opt_iter; | |
1592 | goto validate_return_locked; | |
1593 | } | |
446fda4f PM |
1594 | tag_len = tag[1]; |
1595 | if (tag_len > (opt_len - opt_iter)) { | |
1596 | err_offset = opt_iter + 1; | |
1597 | goto validate_return_locked; | |
1598 | } | |
1599 | ||
1600 | switch (tag[0]) { | |
1601 | case CIPSO_V4_TAG_RBITMAP: | |
15c45f7b | 1602 | if (tag_len < CIPSO_V4_TAG_RBM_BLEN) { |
446fda4f PM |
1603 | err_offset = opt_iter + 1; |
1604 | goto validate_return_locked; | |
1605 | } | |
1606 | ||
1607 | /* We are already going to do all the verification | |
1608 | * necessary at the socket layer so from our point of | |
1609 | * view it is safe to turn these checks off (and less | |
1610 | * work), however, the CIPSO draft says we should do | |
1611 | * all the CIPSO validations here but it doesn't | |
1612 | * really specify _exactly_ what we need to validate | |
1613 | * ... so, just make it a sysctl tunable. */ | |
1614 | if (cipso_v4_rbm_strictvalid) { | |
1615 | if (cipso_v4_map_lvl_valid(doi_def, | |
1616 | tag[3]) < 0) { | |
1617 | err_offset = opt_iter + 3; | |
1618 | goto validate_return_locked; | |
1619 | } | |
15c45f7b | 1620 | if (tag_len > CIPSO_V4_TAG_RBM_BLEN && |
446fda4f PM |
1621 | cipso_v4_map_cat_rbm_valid(doi_def, |
1622 | &tag[4], | |
1623 | tag_len - 4) < 0) { | |
1624 | err_offset = opt_iter + 4; | |
1625 | goto validate_return_locked; | |
1626 | } | |
1627 | } | |
1628 | break; | |
654bbc2a | 1629 | case CIPSO_V4_TAG_ENUM: |
15c45f7b | 1630 | if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) { |
654bbc2a PM |
1631 | err_offset = opt_iter + 1; |
1632 | goto validate_return_locked; | |
1633 | } | |
1634 | ||
1635 | if (cipso_v4_map_lvl_valid(doi_def, | |
1636 | tag[3]) < 0) { | |
1637 | err_offset = opt_iter + 3; | |
1638 | goto validate_return_locked; | |
1639 | } | |
15c45f7b | 1640 | if (tag_len > CIPSO_V4_TAG_ENUM_BLEN && |
654bbc2a PM |
1641 | cipso_v4_map_cat_enum_valid(doi_def, |
1642 | &tag[4], | |
1643 | tag_len - 4) < 0) { | |
1644 | err_offset = opt_iter + 4; | |
1645 | goto validate_return_locked; | |
1646 | } | |
1647 | break; | |
484b3669 | 1648 | case CIPSO_V4_TAG_RANGE: |
15c45f7b | 1649 | if (tag_len < CIPSO_V4_TAG_RNG_BLEN) { |
484b3669 PM |
1650 | err_offset = opt_iter + 1; |
1651 | goto validate_return_locked; | |
1652 | } | |
1653 | ||
1654 | if (cipso_v4_map_lvl_valid(doi_def, | |
1655 | tag[3]) < 0) { | |
1656 | err_offset = opt_iter + 3; | |
1657 | goto validate_return_locked; | |
1658 | } | |
15c45f7b | 1659 | if (tag_len > CIPSO_V4_TAG_RNG_BLEN && |
484b3669 PM |
1660 | cipso_v4_map_cat_rng_valid(doi_def, |
1661 | &tag[4], | |
1662 | tag_len - 4) < 0) { | |
1663 | err_offset = opt_iter + 4; | |
1664 | goto validate_return_locked; | |
1665 | } | |
1666 | break; | |
15c45f7b PM |
1667 | case CIPSO_V4_TAG_LOCAL: |
1668 | /* This is a non-standard tag that we only allow for | |
1669 | * local connections, so if the incoming interface is | |
89d7ae34 PM |
1670 | * not the loopback device drop the packet. Further, |
1671 | * there is no legitimate reason for setting this from | |
1672 | * userspace so reject it if skb is NULL. */ | |
51456b29 | 1673 | if (!skb || !(skb->dev->flags & IFF_LOOPBACK)) { |
15c45f7b PM |
1674 | err_offset = opt_iter; |
1675 | goto validate_return_locked; | |
1676 | } | |
1677 | if (tag_len != CIPSO_V4_TAG_LOC_BLEN) { | |
1678 | err_offset = opt_iter + 1; | |
1679 | goto validate_return_locked; | |
1680 | } | |
1681 | break; | |
446fda4f PM |
1682 | default: |
1683 | err_offset = opt_iter; | |
1684 | goto validate_return_locked; | |
1685 | } | |
1686 | ||
1687 | tag += tag_len; | |
1688 | opt_iter += tag_len; | |
1689 | } | |
1690 | ||
1691 | validate_return_locked: | |
1692 | rcu_read_unlock(); | |
1693 | validate_return: | |
1694 | *option = opt + err_offset; | |
1695 | return err_offset; | |
1696 | } | |
1697 | ||
1698 | /** | |
25985edc | 1699 | * cipso_v4_error - Send the correct response for a bad packet |
446fda4f PM |
1700 | * @skb: the packet |
1701 | * @error: the error code | |
1702 | * @gateway: CIPSO gateway flag | |
1703 | * | |
1704 | * Description: | |
1705 | * Based on the error code given in @error, send an ICMP error message back to | |
1706 | * the originating host. From the IETF draft ... | |
1707 | * | |
1708 | * "If the contents of the CIPSO [option] are valid but the security label is | |
1709 | * outside of the configured host or port label range, the datagram is | |
1710 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and | |
1711 | * returned. The code field of the ICMP is set to 'communication with | |
1712 | * destination network administratively prohibited' (code 9) or to | |
1713 | * 'communication with destination host administratively prohibited' | |
1714 | * (code 10). The value of the code is dependent on whether the originator | |
1715 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The | |
1716 | * recipient of the ICMP message MUST be able to handle either value. The | |
1717 | * same procedure is performed if a CIPSO [option] can not be added to an | |
1718 | * IP packet because it is too large to fit in the IP options area." | |
1719 | * | |
1720 | * "If the error is triggered by receipt of an ICMP message, the message is | |
1721 | * discarded and no response is permitted (consistent with general ICMP | |
1722 | * processing rules)." | |
1723 | * | |
1724 | */ | |
1725 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) | |
1726 | { | |
3da1ed7a NS |
1727 | unsigned char optbuf[sizeof(struct ip_options) + 40]; |
1728 | struct ip_options *opt = (struct ip_options *)optbuf; | |
3e72dfdf | 1729 | int res; |
3da1ed7a | 1730 | |
eddc9ec5 | 1731 | if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) |
446fda4f PM |
1732 | return; |
1733 | ||
3da1ed7a NS |
1734 | /* |
1735 | * We might be called above the IP layer, | |
1736 | * so we can not use icmp_send and IPCB here. | |
1737 | */ | |
1738 | ||
1739 | memset(opt, 0, sizeof(struct ip_options)); | |
1740 | opt->optlen = ip_hdr(skb)->ihl*4 - sizeof(struct iphdr); | |
3e72dfdf MC |
1741 | rcu_read_lock(); |
1742 | res = __ip_options_compile(dev_net(skb->dev), opt, skb, NULL); | |
1743 | rcu_read_unlock(); | |
1744 | ||
1745 | if (res) | |
3da1ed7a NS |
1746 | return; |
1747 | ||
446fda4f | 1748 | if (gateway) |
3da1ed7a | 1749 | __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0, opt); |
446fda4f | 1750 | else |
3da1ed7a | 1751 | __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0, opt); |
446fda4f PM |
1752 | } |
1753 | ||
1754 | /** | |
948bf85c PM |
1755 | * cipso_v4_genopt - Generate a CIPSO option |
1756 | * @buf: the option buffer | |
1757 | * @buf_len: the size of opt_buf | |
446fda4f | 1758 | * @doi_def: the CIPSO DOI to use |
948bf85c | 1759 | * @secattr: the security attributes |
446fda4f PM |
1760 | * |
1761 | * Description: | |
948bf85c PM |
1762 | * Generate a CIPSO option using the DOI definition and security attributes |
1763 | * passed to the function. Returns the length of the option on success and | |
1764 | * negative values on failure. | |
446fda4f PM |
1765 | * |
1766 | */ | |
948bf85c PM |
1767 | static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, |
1768 | const struct cipso_v4_doi *doi_def, | |
1769 | const struct netlbl_lsm_secattr *secattr) | |
446fda4f | 1770 | { |
948bf85c | 1771 | int ret_val; |
446fda4f | 1772 | u32 iter; |
446fda4f | 1773 | |
948bf85c PM |
1774 | if (buf_len <= CIPSO_V4_HDR_LEN) |
1775 | return -ENOSPC; | |
91b1ed0a | 1776 | |
446fda4f PM |
1777 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1778 | * really a good assumption to make but since we only support the MAC | |
1779 | * tags right now it is a safe assumption. */ | |
1780 | iter = 0; | |
1781 | do { | |
91b1ed0a | 1782 | memset(buf, 0, buf_len); |
446fda4f PM |
1783 | switch (doi_def->tags[iter]) { |
1784 | case CIPSO_V4_TAG_RBITMAP: | |
1785 | ret_val = cipso_v4_gentag_rbm(doi_def, | |
91b1ed0a PM |
1786 | secattr, |
1787 | &buf[CIPSO_V4_HDR_LEN], | |
1788 | buf_len - CIPSO_V4_HDR_LEN); | |
446fda4f | 1789 | break; |
654bbc2a PM |
1790 | case CIPSO_V4_TAG_ENUM: |
1791 | ret_val = cipso_v4_gentag_enum(doi_def, | |
1792 | secattr, | |
1793 | &buf[CIPSO_V4_HDR_LEN], | |
1794 | buf_len - CIPSO_V4_HDR_LEN); | |
1795 | break; | |
484b3669 PM |
1796 | case CIPSO_V4_TAG_RANGE: |
1797 | ret_val = cipso_v4_gentag_rng(doi_def, | |
1798 | secattr, | |
1799 | &buf[CIPSO_V4_HDR_LEN], | |
1800 | buf_len - CIPSO_V4_HDR_LEN); | |
1801 | break; | |
15c45f7b PM |
1802 | case CIPSO_V4_TAG_LOCAL: |
1803 | ret_val = cipso_v4_gentag_loc(doi_def, | |
1804 | secattr, | |
1805 | &buf[CIPSO_V4_HDR_LEN], | |
1806 | buf_len - CIPSO_V4_HDR_LEN); | |
1807 | break; | |
446fda4f | 1808 | default: |
948bf85c | 1809 | return -EPERM; |
446fda4f PM |
1810 | } |
1811 | ||
1812 | iter++; | |
91b1ed0a | 1813 | } while (ret_val < 0 && |
446fda4f PM |
1814 | iter < CIPSO_V4_TAG_MAXCNT && |
1815 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); | |
91b1ed0a | 1816 | if (ret_val < 0) |
948bf85c | 1817 | return ret_val; |
91b1ed0a | 1818 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
948bf85c PM |
1819 | return CIPSO_V4_HDR_LEN + ret_val; |
1820 | } | |
1821 | ||
1822 | /** | |
1823 | * cipso_v4_sock_setattr - Add a CIPSO option to a socket | |
1824 | * @sk: the socket | |
1825 | * @doi_def: the CIPSO DOI to use | |
1826 | * @secattr: the specific security attributes of the socket | |
1827 | * | |
1828 | * Description: | |
1829 | * Set the CIPSO option on the given socket using the DOI definition and | |
1830 | * security attributes passed to the function. This function requires | |
1831 | * exclusive access to @sk, which means it either needs to be in the | |
1832 | * process of being created or locked. Returns zero on success and negative | |
1833 | * values on failure. | |
1834 | * | |
1835 | */ | |
1836 | int cipso_v4_sock_setattr(struct sock *sk, | |
1837 | const struct cipso_v4_doi *doi_def, | |
1838 | const struct netlbl_lsm_secattr *secattr) | |
1839 | { | |
1840 | int ret_val = -EPERM; | |
1841 | unsigned char *buf = NULL; | |
1842 | u32 buf_len; | |
1843 | u32 opt_len; | |
f6d8bd05 | 1844 | struct ip_options_rcu *old, *opt = NULL; |
948bf85c PM |
1845 | struct inet_sock *sk_inet; |
1846 | struct inet_connection_sock *sk_conn; | |
1847 | ||
1848 | /* In the case of sock_create_lite(), the sock->sk field is not | |
1849 | * defined yet but it is not a problem as the only users of these | |
1850 | * "lite" PF_INET sockets are functions which do an accept() call | |
1851 | * afterwards so we will label the socket as part of the accept(). */ | |
51456b29 | 1852 | if (!sk) |
948bf85c PM |
1853 | return 0; |
1854 | ||
1855 | /* We allocate the maximum CIPSO option size here so we are probably | |
1856 | * being a little wasteful, but it makes our life _much_ easier later | |
1857 | * on and after all we are only talking about 40 bytes. */ | |
1858 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1859 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
51456b29 | 1860 | if (!buf) { |
948bf85c PM |
1861 | ret_val = -ENOMEM; |
1862 | goto socket_setattr_failure; | |
1863 | } | |
1864 | ||
1865 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1866 | if (ret_val < 0) | |
1867 | goto socket_setattr_failure; | |
1868 | buf_len = ret_val; | |
446fda4f PM |
1869 | |
1870 | /* We can't use ip_options_get() directly because it makes a call to | |
1871 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
f8687afe PM |
1872 | * we won't always have CAP_NET_RAW even though we _always_ want to |
1873 | * set the IPOPT_CIPSO option. */ | |
446fda4f PM |
1874 | opt_len = (buf_len + 3) & ~3; |
1875 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
51456b29 | 1876 | if (!opt) { |
446fda4f PM |
1877 | ret_val = -ENOMEM; |
1878 | goto socket_setattr_failure; | |
1879 | } | |
f6d8bd05 ED |
1880 | memcpy(opt->opt.__data, buf, buf_len); |
1881 | opt->opt.optlen = opt_len; | |
1882 | opt->opt.cipso = sizeof(struct iphdr); | |
446fda4f PM |
1883 | kfree(buf); |
1884 | buf = NULL; | |
446fda4f PM |
1885 | |
1886 | sk_inet = inet_sk(sk); | |
f6d8bd05 | 1887 | |
1e1d04e6 HFS |
1888 | old = rcu_dereference_protected(sk_inet->inet_opt, |
1889 | lockdep_sock_is_held(sk)); | |
446fda4f PM |
1890 | if (sk_inet->is_icsk) { |
1891 | sk_conn = inet_csk(sk); | |
f6d8bd05 ED |
1892 | if (old) |
1893 | sk_conn->icsk_ext_hdr_len -= old->opt.optlen; | |
1894 | sk_conn->icsk_ext_hdr_len += opt->opt.optlen; | |
446fda4f PM |
1895 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); |
1896 | } | |
f6d8bd05 ED |
1897 | rcu_assign_pointer(sk_inet->inet_opt, opt); |
1898 | if (old) | |
4f9c8c1b | 1899 | kfree_rcu(old, rcu); |
446fda4f PM |
1900 | |
1901 | return 0; | |
1902 | ||
1903 | socket_setattr_failure: | |
1904 | kfree(buf); | |
1905 | kfree(opt); | |
1906 | return ret_val; | |
1907 | } | |
1908 | ||
014ab19a | 1909 | /** |
389fb800 PM |
1910 | * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket |
1911 | * @req: the connection request socket | |
1912 | * @doi_def: the CIPSO DOI to use | |
1913 | * @secattr: the specific security attributes of the socket | |
014ab19a PM |
1914 | * |
1915 | * Description: | |
389fb800 PM |
1916 | * Set the CIPSO option on the given socket using the DOI definition and |
1917 | * security attributes passed to the function. Returns zero on success and | |
1918 | * negative values on failure. | |
014ab19a PM |
1919 | * |
1920 | */ | |
389fb800 PM |
1921 | int cipso_v4_req_setattr(struct request_sock *req, |
1922 | const struct cipso_v4_doi *doi_def, | |
1923 | const struct netlbl_lsm_secattr *secattr) | |
014ab19a | 1924 | { |
389fb800 PM |
1925 | int ret_val = -EPERM; |
1926 | unsigned char *buf = NULL; | |
1927 | u32 buf_len; | |
1928 | u32 opt_len; | |
f6d8bd05 | 1929 | struct ip_options_rcu *opt = NULL; |
389fb800 | 1930 | struct inet_request_sock *req_inet; |
014ab19a | 1931 | |
389fb800 PM |
1932 | /* We allocate the maximum CIPSO option size here so we are probably |
1933 | * being a little wasteful, but it makes our life _much_ easier later | |
1934 | * on and after all we are only talking about 40 bytes. */ | |
1935 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1936 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
51456b29 | 1937 | if (!buf) { |
389fb800 PM |
1938 | ret_val = -ENOMEM; |
1939 | goto req_setattr_failure; | |
1940 | } | |
1941 | ||
1942 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1943 | if (ret_val < 0) | |
1944 | goto req_setattr_failure; | |
1945 | buf_len = ret_val; | |
1946 | ||
1947 | /* We can't use ip_options_get() directly because it makes a call to | |
1948 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
1949 | * we won't always have CAP_NET_RAW even though we _always_ want to | |
1950 | * set the IPOPT_CIPSO option. */ | |
1951 | opt_len = (buf_len + 3) & ~3; | |
1952 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
51456b29 | 1953 | if (!opt) { |
389fb800 PM |
1954 | ret_val = -ENOMEM; |
1955 | goto req_setattr_failure; | |
1956 | } | |
f6d8bd05 ED |
1957 | memcpy(opt->opt.__data, buf, buf_len); |
1958 | opt->opt.optlen = opt_len; | |
1959 | opt->opt.cipso = sizeof(struct iphdr); | |
389fb800 PM |
1960 | kfree(buf); |
1961 | buf = NULL; | |
1962 | ||
1963 | req_inet = inet_rsk(req); | |
c92e8c02 | 1964 | opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt); |
f6d8bd05 | 1965 | if (opt) |
4f9c8c1b | 1966 | kfree_rcu(opt, rcu); |
389fb800 PM |
1967 | |
1968 | return 0; | |
1969 | ||
1970 | req_setattr_failure: | |
1971 | kfree(buf); | |
1972 | kfree(opt); | |
1973 | return ret_val; | |
1974 | } | |
1975 | ||
1976 | /** | |
1977 | * cipso_v4_delopt - Delete the CIPSO option from a set of IP options | |
1978 | * @opt_ptr: IP option pointer | |
1979 | * | |
1980 | * Description: | |
1981 | * Deletes the CIPSO IP option from a set of IP options and makes the necessary | |
1982 | * adjustments to the IP option structure. Returns zero on success, negative | |
1983 | * values on failure. | |
1984 | * | |
1985 | */ | |
c92e8c02 | 1986 | static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr) |
389fb800 | 1987 | { |
c92e8c02 | 1988 | struct ip_options_rcu *opt = rcu_dereference_protected(*opt_ptr, 1); |
389fb800 | 1989 | int hdr_delta = 0; |
014ab19a | 1990 | |
c92e8c02 ED |
1991 | if (!opt || opt->opt.cipso == 0) |
1992 | return 0; | |
f6d8bd05 | 1993 | if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) { |
014ab19a PM |
1994 | u8 cipso_len; |
1995 | u8 cipso_off; | |
1996 | unsigned char *cipso_ptr; | |
1997 | int iter; | |
1998 | int optlen_new; | |
1999 | ||
f6d8bd05 ED |
2000 | cipso_off = opt->opt.cipso - sizeof(struct iphdr); |
2001 | cipso_ptr = &opt->opt.__data[cipso_off]; | |
014ab19a PM |
2002 | cipso_len = cipso_ptr[1]; |
2003 | ||
f6d8bd05 ED |
2004 | if (opt->opt.srr > opt->opt.cipso) |
2005 | opt->opt.srr -= cipso_len; | |
2006 | if (opt->opt.rr > opt->opt.cipso) | |
2007 | opt->opt.rr -= cipso_len; | |
2008 | if (opt->opt.ts > opt->opt.cipso) | |
2009 | opt->opt.ts -= cipso_len; | |
2010 | if (opt->opt.router_alert > opt->opt.cipso) | |
2011 | opt->opt.router_alert -= cipso_len; | |
2012 | opt->opt.cipso = 0; | |
014ab19a PM |
2013 | |
2014 | memmove(cipso_ptr, cipso_ptr + cipso_len, | |
f6d8bd05 | 2015 | opt->opt.optlen - cipso_off - cipso_len); |
014ab19a PM |
2016 | |
2017 | /* determining the new total option length is tricky because of | |
2018 | * the padding necessary, the only thing i can think to do at | |
2019 | * this point is walk the options one-by-one, skipping the | |
2020 | * padding at the end to determine the actual option size and | |
2021 | * from there we can determine the new total option length */ | |
2022 | iter = 0; | |
2023 | optlen_new = 0; | |
f6d8bd05 ED |
2024 | while (iter < opt->opt.optlen) |
2025 | if (opt->opt.__data[iter] != IPOPT_NOP) { | |
2026 | iter += opt->opt.__data[iter + 1]; | |
014ab19a PM |
2027 | optlen_new = iter; |
2028 | } else | |
2029 | iter++; | |
f6d8bd05 ED |
2030 | hdr_delta = opt->opt.optlen; |
2031 | opt->opt.optlen = (optlen_new + 3) & ~3; | |
2032 | hdr_delta -= opt->opt.optlen; | |
014ab19a PM |
2033 | } else { |
2034 | /* only the cipso option was present on the socket so we can | |
2035 | * remove the entire option struct */ | |
389fb800 | 2036 | *opt_ptr = NULL; |
f6d8bd05 | 2037 | hdr_delta = opt->opt.optlen; |
4f9c8c1b | 2038 | kfree_rcu(opt, rcu); |
014ab19a PM |
2039 | } |
2040 | ||
389fb800 PM |
2041 | return hdr_delta; |
2042 | } | |
2043 | ||
2044 | /** | |
2045 | * cipso_v4_sock_delattr - Delete the CIPSO option from a socket | |
2046 | * @sk: the socket | |
2047 | * | |
2048 | * Description: | |
2049 | * Removes the CIPSO option from a socket, if present. | |
2050 | * | |
2051 | */ | |
2052 | void cipso_v4_sock_delattr(struct sock *sk) | |
2053 | { | |
389fb800 | 2054 | struct inet_sock *sk_inet; |
c92e8c02 | 2055 | int hdr_delta; |
389fb800 PM |
2056 | |
2057 | sk_inet = inet_sk(sk); | |
389fb800 | 2058 | |
f6d8bd05 | 2059 | hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt); |
014ab19a PM |
2060 | if (sk_inet->is_icsk && hdr_delta > 0) { |
2061 | struct inet_connection_sock *sk_conn = inet_csk(sk); | |
2062 | sk_conn->icsk_ext_hdr_len -= hdr_delta; | |
2063 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
2064 | } | |
2065 | } | |
2066 | ||
389fb800 PM |
2067 | /** |
2068 | * cipso_v4_req_delattr - Delete the CIPSO option from a request socket | |
2069 | * @reg: the request socket | |
2070 | * | |
2071 | * Description: | |
2072 | * Removes the CIPSO option from a request socket, if present. | |
2073 | * | |
2074 | */ | |
2075 | void cipso_v4_req_delattr(struct request_sock *req) | |
2076 | { | |
c92e8c02 | 2077 | cipso_v4_delopt(&inet_rsk(req)->ireq_opt); |
389fb800 PM |
2078 | } |
2079 | ||
446fda4f | 2080 | /** |
63d804ea PM |
2081 | * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions |
2082 | * @cipso: the CIPSO v4 option | |
446fda4f PM |
2083 | * @secattr: the security attributes |
2084 | * | |
2085 | * Description: | |
63d804ea PM |
2086 | * Inspect @cipso and return the security attributes in @secattr. Returns zero |
2087 | * on success and negative values on failure. | |
446fda4f PM |
2088 | * |
2089 | */ | |
04f81f01 PM |
2090 | int cipso_v4_getattr(const unsigned char *cipso, |
2091 | struct netlbl_lsm_secattr *secattr) | |
446fda4f PM |
2092 | { |
2093 | int ret_val = -ENOMSG; | |
446fda4f PM |
2094 | u32 doi; |
2095 | struct cipso_v4_doi *doi_def; | |
2096 | ||
63d804ea PM |
2097 | if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0) |
2098 | return 0; | |
446fda4f | 2099 | |
d3e2ce3b | 2100 | doi = get_unaligned_be32(&cipso[2]); |
446fda4f | 2101 | rcu_read_lock(); |
9bb5fd2b | 2102 | doi_def = cipso_v4_doi_search(doi); |
51456b29 | 2103 | if (!doi_def) |
63d804ea | 2104 | goto getattr_return; |
91b1ed0a PM |
2105 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
2106 | * really a good assumption to make but since we only support the MAC | |
2107 | * tags right now it is a safe assumption. */ | |
63d804ea | 2108 | switch (cipso[6]) { |
446fda4f | 2109 | case CIPSO_V4_TAG_RBITMAP: |
63d804ea | 2110 | ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr); |
446fda4f | 2111 | break; |
654bbc2a | 2112 | case CIPSO_V4_TAG_ENUM: |
63d804ea | 2113 | ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr); |
654bbc2a | 2114 | break; |
484b3669 | 2115 | case CIPSO_V4_TAG_RANGE: |
63d804ea | 2116 | ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr); |
484b3669 | 2117 | break; |
15c45f7b PM |
2118 | case CIPSO_V4_TAG_LOCAL: |
2119 | ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr); | |
2120 | break; | |
446fda4f | 2121 | } |
16efd454 PM |
2122 | if (ret_val == 0) |
2123 | secattr->type = NETLBL_NLTYPE_CIPSOV4; | |
446fda4f | 2124 | |
63d804ea PM |
2125 | getattr_return: |
2126 | rcu_read_unlock(); | |
14a72f53 PM |
2127 | return ret_val; |
2128 | } | |
2129 | ||
63d804ea PM |
2130 | /** |
2131 | * cipso_v4_sock_getattr - Get the security attributes from a sock | |
2132 | * @sk: the sock | |
2133 | * @secattr: the security attributes | |
2134 | * | |
2135 | * Description: | |
2136 | * Query @sk to see if there is a CIPSO option attached to the sock and if | |
2137 | * there is return the CIPSO security attributes in @secattr. This function | |
2138 | * requires that @sk be locked, or privately held, but it does not do any | |
2139 | * locking itself. Returns zero on success and negative values on failure. | |
2140 | * | |
2141 | */ | |
2142 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) | |
2143 | { | |
f6d8bd05 ED |
2144 | struct ip_options_rcu *opt; |
2145 | int res = -ENOMSG; | |
63d804ea | 2146 | |
f6d8bd05 ED |
2147 | rcu_read_lock(); |
2148 | opt = rcu_dereference(inet_sk(sk)->inet_opt); | |
2149 | if (opt && opt->opt.cipso) | |
2150 | res = cipso_v4_getattr(opt->opt.__data + | |
2151 | opt->opt.cipso - | |
2152 | sizeof(struct iphdr), | |
2153 | secattr); | |
2154 | rcu_read_unlock(); | |
2155 | return res; | |
63d804ea PM |
2156 | } |
2157 | ||
948bf85c PM |
2158 | /** |
2159 | * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet | |
2160 | * @skb: the packet | |
2161 | * @secattr: the security attributes | |
2162 | * | |
2163 | * Description: | |
2164 | * Set the CIPSO option on the given packet based on the security attributes. | |
2165 | * Returns a pointer to the IP header on success and NULL on failure. | |
2166 | * | |
2167 | */ | |
2168 | int cipso_v4_skbuff_setattr(struct sk_buff *skb, | |
2169 | const struct cipso_v4_doi *doi_def, | |
2170 | const struct netlbl_lsm_secattr *secattr) | |
2171 | { | |
2172 | int ret_val; | |
2173 | struct iphdr *iph; | |
2174 | struct ip_options *opt = &IPCB(skb)->opt; | |
2175 | unsigned char buf[CIPSO_V4_OPT_LEN_MAX]; | |
2176 | u32 buf_len = CIPSO_V4_OPT_LEN_MAX; | |
2177 | u32 opt_len; | |
2178 | int len_delta; | |
2179 | ||
00af5c69 | 2180 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); |
2181 | if (ret_val < 0) | |
2182 | return ret_val; | |
2183 | buf_len = ret_val; | |
948bf85c PM |
2184 | opt_len = (buf_len + 3) & ~3; |
2185 | ||
2186 | /* we overwrite any existing options to ensure that we have enough | |
2187 | * room for the CIPSO option, the reason is that we _need_ to guarantee | |
2188 | * that the security label is applied to the packet - we do the same | |
2189 | * thing when using the socket options and it hasn't caused a problem, | |
2190 | * if we need to we can always revisit this choice later */ | |
2191 | ||
2192 | len_delta = opt_len - opt->optlen; | |
2193 | /* if we don't ensure enough headroom we could panic on the skb_push() | |
2194 | * call below so make sure we have enough, we are also "mangling" the | |
2195 | * packet so we should probably do a copy-on-write call anyway */ | |
2196 | ret_val = skb_cow(skb, skb_headroom(skb) + len_delta); | |
2197 | if (ret_val < 0) | |
2198 | return ret_val; | |
2199 | ||
2200 | if (len_delta > 0) { | |
2201 | /* we assume that the header + opt->optlen have already been | |
2202 | * "pushed" in ip_options_build() or similar */ | |
2203 | iph = ip_hdr(skb); | |
2204 | skb_push(skb, len_delta); | |
2205 | memmove((char *)iph - len_delta, iph, iph->ihl << 2); | |
2206 | skb_reset_network_header(skb); | |
2207 | iph = ip_hdr(skb); | |
2208 | } else if (len_delta < 0) { | |
2209 | iph = ip_hdr(skb); | |
2210 | memset(iph + 1, IPOPT_NOP, opt->optlen); | |
2211 | } else | |
2212 | iph = ip_hdr(skb); | |
2213 | ||
2214 | if (opt->optlen > 0) | |
2215 | memset(opt, 0, sizeof(*opt)); | |
2216 | opt->optlen = opt_len; | |
2217 | opt->cipso = sizeof(struct iphdr); | |
2218 | opt->is_changed = 1; | |
2219 | ||
2220 | /* we have to do the following because we are being called from a | |
2221 | * netfilter hook which means the packet already has had the header | |
2222 | * fields populated and the checksum calculated - yes this means we | |
2223 | * are doing more work than needed but we do it to keep the core | |
2224 | * stack clean and tidy */ | |
2225 | memcpy(iph + 1, buf, buf_len); | |
2226 | if (opt_len > buf_len) | |
2227 | memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); | |
2228 | if (len_delta != 0) { | |
2229 | iph->ihl = 5 + (opt_len >> 2); | |
2230 | iph->tot_len = htons(skb->len); | |
2231 | } | |
2232 | ip_send_check(iph); | |
2233 | ||
2234 | return 0; | |
2235 | } | |
2236 | ||
2237 | /** | |
2238 | * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet | |
2239 | * @skb: the packet | |
2240 | * | |
2241 | * Description: | |
2242 | * Removes any and all CIPSO options from the given packet. Returns zero on | |
2243 | * success, negative values on failure. | |
2244 | * | |
2245 | */ | |
2246 | int cipso_v4_skbuff_delattr(struct sk_buff *skb) | |
2247 | { | |
2248 | int ret_val; | |
2249 | struct iphdr *iph; | |
2250 | struct ip_options *opt = &IPCB(skb)->opt; | |
2251 | unsigned char *cipso_ptr; | |
2252 | ||
2253 | if (opt->cipso == 0) | |
2254 | return 0; | |
2255 | ||
2256 | /* since we are changing the packet we should make a copy */ | |
2257 | ret_val = skb_cow(skb, skb_headroom(skb)); | |
2258 | if (ret_val < 0) | |
2259 | return ret_val; | |
2260 | ||
2261 | /* the easiest thing to do is just replace the cipso option with noop | |
2262 | * options since we don't change the size of the packet, although we | |
2263 | * still need to recalculate the checksum */ | |
2264 | ||
2265 | iph = ip_hdr(skb); | |
2266 | cipso_ptr = (unsigned char *)iph + opt->cipso; | |
2267 | memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); | |
2268 | opt->cipso = 0; | |
2269 | opt->is_changed = 1; | |
2270 | ||
2271 | ip_send_check(iph); | |
2272 | ||
2273 | return 0; | |
2274 | } | |
2275 | ||
446fda4f PM |
2276 | /* |
2277 | * Setup Functions | |
2278 | */ | |
2279 | ||
2280 | /** | |
2281 | * cipso_v4_init - Initialize the CIPSO module | |
2282 | * | |
2283 | * Description: | |
2284 | * Initialize the CIPSO module and prepare it for use. Returns zero on success | |
2285 | * and negative values on failure. | |
2286 | * | |
2287 | */ | |
2288 | static int __init cipso_v4_init(void) | |
2289 | { | |
2290 | int ret_val; | |
2291 | ||
2292 | ret_val = cipso_v4_cache_init(); | |
2293 | if (ret_val != 0) | |
2294 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", | |
2295 | ret_val); | |
2296 | ||
2297 | return 0; | |
2298 | } | |
2299 | ||
2300 | subsys_initcall(cipso_v4_init); |