Commit | Line | Data |
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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: | |
7a6498eb | 13 | * https://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt |
586c2500 | 14 | * The FIPS-188 specification can be found at the following URL: |
7a6498eb | 15 | * https://www.itl.nist.gov/fipspubs/fip188.htm |
586c2500 | 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 | 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 | 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 | |
3628e3cb | 286 | * @cipso_ptr: pointer to CIPSO IP option |
446fda4f PM |
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 | |
7edce636 | 501 | * @audit_info: NetLabel audit information |
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 | } |
b1edeb10 | 522 | list_del_rcu(&doi_def->list); |
4be2700f | 523 | spin_unlock(&cipso_v4_doi_list_lock); |
446fda4f | 524 | |
ad5d07f4 | 525 | cipso_v4_doi_putdef(doi_def); |
6c2e8ac0 PM |
526 | ret_val = 0; |
527 | ||
528 | doi_remove_return: | |
529 | audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info); | |
00db4124 | 530 | if (audit_buf) { |
6c2e8ac0 PM |
531 | audit_log_format(audit_buf, |
532 | " cipso_doi=%u res=%u", | |
533 | doi, ret_val == 0 ? 1 : 0); | |
534 | audit_log_end(audit_buf); | |
535 | } | |
b1edeb10 | 536 | |
6c2e8ac0 | 537 | return ret_val; |
446fda4f PM |
538 | } |
539 | ||
540 | /** | |
b1edeb10 | 541 | * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition |
446fda4f PM |
542 | * @doi: the DOI value |
543 | * | |
544 | * Description: | |
545 | * Searches for a valid DOI definition and if one is found it is returned to | |
546 | * the caller. Otherwise NULL is returned. The caller must ensure that | |
b1edeb10 PM |
547 | * rcu_read_lock() is held while accessing the returned definition and the DOI |
548 | * definition reference count is decremented when the caller is done. | |
446fda4f PM |
549 | * |
550 | */ | |
551 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) | |
552 | { | |
b1edeb10 PM |
553 | struct cipso_v4_doi *doi_def; |
554 | ||
555 | rcu_read_lock(); | |
556 | doi_def = cipso_v4_doi_search(doi); | |
51456b29 | 557 | if (!doi_def) |
b1edeb10 | 558 | goto doi_getdef_return; |
f6a6fede | 559 | if (!refcount_inc_not_zero(&doi_def->refcount)) |
b1edeb10 PM |
560 | doi_def = NULL; |
561 | ||
562 | doi_getdef_return: | |
563 | rcu_read_unlock(); | |
564 | return doi_def; | |
565 | } | |
566 | ||
567 | /** | |
568 | * cipso_v4_doi_putdef - Releases a reference for the given DOI definition | |
569 | * @doi_def: the DOI definition | |
570 | * | |
571 | * Description: | |
572 | * Releases a DOI definition reference obtained from cipso_v4_doi_getdef(). | |
573 | * | |
574 | */ | |
575 | void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) | |
576 | { | |
51456b29 | 577 | if (!doi_def) |
b1edeb10 PM |
578 | return; |
579 | ||
f6a6fede | 580 | if (!refcount_dec_and_test(&doi_def->refcount)) |
b1edeb10 | 581 | return; |
b1edeb10 PM |
582 | |
583 | cipso_v4_cache_invalidate(); | |
584 | call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); | |
446fda4f PM |
585 | } |
586 | ||
587 | /** | |
fcd48280 PM |
588 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
589 | * @skip_cnt: skip past this number of DOI definitions, updated | |
590 | * @callback: callback for each DOI definition | |
591 | * @cb_arg: argument for the callback function | |
446fda4f PM |
592 | * |
593 | * Description: | |
fcd48280 PM |
594 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
595 | * For each entry call @callback, if @callback returns a negative value stop | |
596 | * 'walking' through the list and return. Updates the value in @skip_cnt upon | |
597 | * return. Returns zero on success, negative values on failure. | |
446fda4f PM |
598 | * |
599 | */ | |
fcd48280 PM |
600 | int cipso_v4_doi_walk(u32 *skip_cnt, |
601 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), | |
602 | void *cb_arg) | |
446fda4f | 603 | { |
fcd48280 | 604 | int ret_val = -ENOENT; |
446fda4f | 605 | u32 doi_cnt = 0; |
fcd48280 | 606 | struct cipso_v4_doi *iter_doi; |
446fda4f | 607 | |
446fda4f | 608 | rcu_read_lock(); |
fcd48280 | 609 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
f6a6fede | 610 | if (refcount_read(&iter_doi->refcount) > 0) { |
fcd48280 PM |
611 | if (doi_cnt++ < *skip_cnt) |
612 | continue; | |
613 | ret_val = callback(iter_doi, cb_arg); | |
614 | if (ret_val < 0) { | |
615 | doi_cnt--; | |
616 | goto doi_walk_return; | |
446fda4f | 617 | } |
446fda4f | 618 | } |
446fda4f | 619 | |
fcd48280 | 620 | doi_walk_return: |
446fda4f | 621 | rcu_read_unlock(); |
fcd48280 PM |
622 | *skip_cnt = doi_cnt; |
623 | return ret_val; | |
446fda4f PM |
624 | } |
625 | ||
446fda4f PM |
626 | /* |
627 | * Label Mapping Functions | |
628 | */ | |
629 | ||
630 | /** | |
631 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood | |
632 | * @doi_def: the DOI definition | |
633 | * @level: the level to check | |
634 | * | |
635 | * Description: | |
636 | * Checks the given level against the given DOI definition and returns a | |
637 | * negative value if the level does not have a valid mapping and a zero value | |
638 | * if the level is defined by the DOI. | |
639 | * | |
640 | */ | |
641 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) | |
642 | { | |
643 | switch (doi_def->type) { | |
644 | case CIPSO_V4_MAP_PASS: | |
645 | return 0; | |
15c45f7b | 646 | case CIPSO_V4_MAP_TRANS: |
5578de48 PM |
647 | if ((level < doi_def->map.std->lvl.cipso_size) && |
648 | (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)) | |
446fda4f PM |
649 | return 0; |
650 | break; | |
651 | } | |
652 | ||
653 | return -EFAULT; | |
654 | } | |
655 | ||
656 | /** | |
657 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network | |
658 | * @doi_def: the DOI definition | |
659 | * @host_lvl: the host MLS level | |
660 | * @net_lvl: the network/CIPSO MLS level | |
661 | * | |
662 | * Description: | |
663 | * Perform a label mapping to translate a local MLS level to the correct | |
664 | * CIPSO level using the given DOI definition. Returns zero on success, | |
665 | * negative values otherwise. | |
666 | * | |
667 | */ | |
668 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, | |
669 | u32 host_lvl, | |
670 | u32 *net_lvl) | |
671 | { | |
672 | switch (doi_def->type) { | |
673 | case CIPSO_V4_MAP_PASS: | |
674 | *net_lvl = host_lvl; | |
675 | return 0; | |
15c45f7b | 676 | case CIPSO_V4_MAP_TRANS: |
c6387a86 PM |
677 | if (host_lvl < doi_def->map.std->lvl.local_size && |
678 | doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) { | |
446fda4f PM |
679 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
680 | return 0; | |
681 | } | |
c6387a86 | 682 | return -EPERM; |
446fda4f PM |
683 | } |
684 | ||
685 | return -EINVAL; | |
686 | } | |
687 | ||
688 | /** | |
689 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host | |
690 | * @doi_def: the DOI definition | |
691 | * @net_lvl: the network/CIPSO MLS level | |
692 | * @host_lvl: the host MLS level | |
693 | * | |
694 | * Description: | |
695 | * Perform a label mapping to translate a CIPSO level to the correct local MLS | |
696 | * level using the given DOI definition. Returns zero on success, negative | |
697 | * values otherwise. | |
698 | * | |
699 | */ | |
700 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, | |
701 | u32 net_lvl, | |
702 | u32 *host_lvl) | |
703 | { | |
704 | struct cipso_v4_std_map_tbl *map_tbl; | |
705 | ||
706 | switch (doi_def->type) { | |
707 | case CIPSO_V4_MAP_PASS: | |
708 | *host_lvl = net_lvl; | |
709 | return 0; | |
15c45f7b | 710 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
711 | map_tbl = doi_def->map.std; |
712 | if (net_lvl < map_tbl->lvl.cipso_size && | |
713 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { | |
714 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; | |
715 | return 0; | |
716 | } | |
c6387a86 | 717 | return -EPERM; |
446fda4f PM |
718 | } |
719 | ||
720 | return -EINVAL; | |
721 | } | |
722 | ||
723 | /** | |
724 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid | |
725 | * @doi_def: the DOI definition | |
726 | * @bitmap: category bitmap | |
727 | * @bitmap_len: bitmap length in bytes | |
728 | * | |
729 | * Description: | |
730 | * Checks the given category bitmap against the given DOI definition and | |
731 | * returns a negative value if any of the categories in the bitmap do not have | |
732 | * a valid mapping and a zero value if all of the categories are valid. | |
733 | * | |
734 | */ | |
735 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, | |
736 | const unsigned char *bitmap, | |
737 | u32 bitmap_len) | |
738 | { | |
739 | int cat = -1; | |
740 | u32 bitmap_len_bits = bitmap_len * 8; | |
044a68ed PM |
741 | u32 cipso_cat_size; |
742 | u32 *cipso_array; | |
446fda4f PM |
743 | |
744 | switch (doi_def->type) { | |
745 | case CIPSO_V4_MAP_PASS: | |
746 | return 0; | |
15c45f7b | 747 | case CIPSO_V4_MAP_TRANS: |
044a68ed PM |
748 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
749 | cipso_array = doi_def->map.std->cat.cipso; | |
446fda4f | 750 | for (;;) { |
3faa8f98 HD |
751 | cat = netlbl_bitmap_walk(bitmap, |
752 | bitmap_len_bits, | |
753 | cat + 1, | |
754 | 1); | |
446fda4f PM |
755 | if (cat < 0) |
756 | break; | |
757 | if (cat >= cipso_cat_size || | |
758 | cipso_array[cat] >= CIPSO_V4_INV_CAT) | |
759 | return -EFAULT; | |
760 | } | |
761 | ||
762 | if (cat == -1) | |
763 | return 0; | |
764 | break; | |
765 | } | |
766 | ||
767 | return -EFAULT; | |
768 | } | |
769 | ||
770 | /** | |
771 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network | |
772 | * @doi_def: the DOI definition | |
02752760 | 773 | * @secattr: the security attributes |
446fda4f PM |
774 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
775 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
776 | * | |
777 | * Description: | |
778 | * Perform a label mapping to translate a local MLS category bitmap to the | |
779 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum | |
780 | * size in bytes of the network bitmap on success, negative values otherwise. | |
781 | * | |
782 | */ | |
783 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, | |
02752760 | 784 | const struct netlbl_lsm_secattr *secattr, |
446fda4f PM |
785 | unsigned char *net_cat, |
786 | u32 net_cat_len) | |
787 | { | |
788 | int host_spot = -1; | |
02752760 | 789 | u32 net_spot = CIPSO_V4_INV_CAT; |
446fda4f | 790 | u32 net_spot_max = 0; |
446fda4f | 791 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
792 | u32 host_cat_size = 0; |
793 | u32 *host_cat_array = NULL; | |
446fda4f | 794 | |
15c45f7b | 795 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
796 | host_cat_size = doi_def->map.std->cat.local_size; |
797 | host_cat_array = doi_def->map.std->cat.local; | |
02752760 PM |
798 | } |
799 | ||
800 | for (;;) { | |
4fbe63d1 PM |
801 | host_spot = netlbl_catmap_walk(secattr->attr.mls.cat, |
802 | host_spot + 1); | |
02752760 PM |
803 | if (host_spot < 0) |
804 | break; | |
805 | ||
806 | switch (doi_def->type) { | |
807 | case CIPSO_V4_MAP_PASS: | |
808 | net_spot = host_spot; | |
809 | break; | |
15c45f7b | 810 | case CIPSO_V4_MAP_TRANS: |
446fda4f PM |
811 | if (host_spot >= host_cat_size) |
812 | return -EPERM; | |
446fda4f | 813 | net_spot = host_cat_array[host_spot]; |
9fade4bf PM |
814 | if (net_spot >= CIPSO_V4_INV_CAT) |
815 | return -EPERM; | |
02752760 | 816 | break; |
446fda4f | 817 | } |
02752760 PM |
818 | if (net_spot >= net_clen_bits) |
819 | return -ENOSPC; | |
3faa8f98 | 820 | netlbl_bitmap_setbit(net_cat, net_spot, 1); |
446fda4f | 821 | |
02752760 PM |
822 | if (net_spot > net_spot_max) |
823 | net_spot_max = net_spot; | |
446fda4f PM |
824 | } |
825 | ||
02752760 PM |
826 | if (++net_spot_max % 8) |
827 | return net_spot_max / 8 + 1; | |
828 | return net_spot_max / 8; | |
446fda4f PM |
829 | } |
830 | ||
831 | /** | |
832 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host | |
833 | * @doi_def: the DOI definition | |
834 | * @net_cat: the category bitmap in network/CIPSO format | |
835 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
02752760 | 836 | * @secattr: the security attributes |
446fda4f PM |
837 | * |
838 | * Description: | |
839 | * Perform a label mapping to translate a CIPSO bitmap to the correct local | |
02752760 PM |
840 | * MLS category bitmap using the given DOI definition. Returns zero on |
841 | * success, negative values on failure. | |
446fda4f PM |
842 | * |
843 | */ | |
844 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, | |
845 | const unsigned char *net_cat, | |
846 | u32 net_cat_len, | |
02752760 | 847 | struct netlbl_lsm_secattr *secattr) |
446fda4f | 848 | { |
02752760 | 849 | int ret_val; |
446fda4f | 850 | int net_spot = -1; |
02752760 | 851 | u32 host_spot = CIPSO_V4_INV_CAT; |
446fda4f | 852 | u32 net_clen_bits = net_cat_len * 8; |
02752760 PM |
853 | u32 net_cat_size = 0; |
854 | u32 *net_cat_array = NULL; | |
446fda4f | 855 | |
15c45f7b | 856 | if (doi_def->type == CIPSO_V4_MAP_TRANS) { |
044a68ed PM |
857 | net_cat_size = doi_def->map.std->cat.cipso_size; |
858 | net_cat_array = doi_def->map.std->cat.cipso; | |
02752760 | 859 | } |
446fda4f | 860 | |
02752760 | 861 | for (;;) { |
3faa8f98 HD |
862 | net_spot = netlbl_bitmap_walk(net_cat, |
863 | net_clen_bits, | |
864 | net_spot + 1, | |
865 | 1); | |
02752760 PM |
866 | if (net_spot < 0) { |
867 | if (net_spot == -2) | |
868 | return -EFAULT; | |
869 | return 0; | |
870 | } | |
871 | ||
872 | switch (doi_def->type) { | |
873 | case CIPSO_V4_MAP_PASS: | |
874 | host_spot = net_spot; | |
875 | break; | |
15c45f7b | 876 | case CIPSO_V4_MAP_TRANS: |
02752760 PM |
877 | if (net_spot >= net_cat_size) |
878 | return -EPERM; | |
446fda4f | 879 | host_spot = net_cat_array[net_spot]; |
9fade4bf PM |
880 | if (host_spot >= CIPSO_V4_INV_CAT) |
881 | return -EPERM; | |
02752760 | 882 | break; |
446fda4f | 883 | } |
4fbe63d1 | 884 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
02752760 PM |
885 | host_spot, |
886 | GFP_ATOMIC); | |
887 | if (ret_val != 0) | |
888 | return ret_val; | |
446fda4f PM |
889 | } |
890 | ||
891 | return -EINVAL; | |
892 | } | |
893 | ||
654bbc2a PM |
894 | /** |
895 | * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid | |
896 | * @doi_def: the DOI definition | |
897 | * @enumcat: category list | |
898 | * @enumcat_len: length of the category list in bytes | |
899 | * | |
900 | * Description: | |
901 | * Checks the given categories against the given DOI definition and returns a | |
902 | * negative value if any of the categories do not have a valid mapping and a | |
903 | * zero value if all of the categories are valid. | |
904 | * | |
905 | */ | |
906 | static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, | |
907 | const unsigned char *enumcat, | |
908 | u32 enumcat_len) | |
909 | { | |
910 | u16 cat; | |
911 | int cat_prev = -1; | |
912 | u32 iter; | |
913 | ||
914 | if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01) | |
915 | return -EFAULT; | |
916 | ||
917 | for (iter = 0; iter < enumcat_len; iter += 2) { | |
d3e2ce3b | 918 | cat = get_unaligned_be16(&enumcat[iter]); |
654bbc2a PM |
919 | if (cat <= cat_prev) |
920 | return -EFAULT; | |
921 | cat_prev = cat; | |
922 | } | |
923 | ||
924 | return 0; | |
925 | } | |
926 | ||
927 | /** | |
928 | * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network | |
929 | * @doi_def: the DOI definition | |
930 | * @secattr: the security attributes | |
931 | * @net_cat: the zero'd out category list in network/CIPSO format | |
932 | * @net_cat_len: the length of the CIPSO category list in bytes | |
933 | * | |
934 | * Description: | |
935 | * Perform a label mapping to translate a local MLS category bitmap to the | |
936 | * correct CIPSO category list using the given DOI definition. Returns the | |
937 | * size in bytes of the network category bitmap on success, negative values | |
938 | * otherwise. | |
939 | * | |
940 | */ | |
941 | static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, | |
942 | const struct netlbl_lsm_secattr *secattr, | |
943 | unsigned char *net_cat, | |
944 | u32 net_cat_len) | |
945 | { | |
946 | int cat = -1; | |
947 | u32 cat_iter = 0; | |
948 | ||
949 | for (;;) { | |
4fbe63d1 | 950 | cat = netlbl_catmap_walk(secattr->attr.mls.cat, cat + 1); |
654bbc2a PM |
951 | if (cat < 0) |
952 | break; | |
953 | if ((cat_iter + 2) > net_cat_len) | |
954 | return -ENOSPC; | |
955 | ||
956 | *((__be16 *)&net_cat[cat_iter]) = htons(cat); | |
957 | cat_iter += 2; | |
958 | } | |
959 | ||
960 | return cat_iter; | |
961 | } | |
962 | ||
963 | /** | |
964 | * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host | |
965 | * @doi_def: the DOI definition | |
966 | * @net_cat: the category list in network/CIPSO format | |
967 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
968 | * @secattr: the security attributes | |
969 | * | |
970 | * Description: | |
971 | * Perform a label mapping to translate a CIPSO category list to the correct | |
972 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
973 | * success, negative values on failure. | |
974 | * | |
975 | */ | |
976 | static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, | |
977 | const unsigned char *net_cat, | |
978 | u32 net_cat_len, | |
979 | struct netlbl_lsm_secattr *secattr) | |
980 | { | |
981 | int ret_val; | |
982 | u32 iter; | |
983 | ||
984 | for (iter = 0; iter < net_cat_len; iter += 2) { | |
4fbe63d1 PM |
985 | ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat, |
986 | get_unaligned_be16(&net_cat[iter]), | |
987 | GFP_ATOMIC); | |
654bbc2a PM |
988 | if (ret_val != 0) |
989 | return ret_val; | |
990 | } | |
991 | ||
992 | return 0; | |
993 | } | |
994 | ||
484b3669 PM |
995 | /** |
996 | * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid | |
997 | * @doi_def: the DOI definition | |
998 | * @rngcat: category list | |
999 | * @rngcat_len: length of the category list in bytes | |
1000 | * | |
1001 | * Description: | |
1002 | * Checks the given categories against the given DOI definition and returns a | |
1003 | * negative value if any of the categories do not have a valid mapping and a | |
1004 | * zero value if all of the categories are valid. | |
1005 | * | |
1006 | */ | |
1007 | static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, | |
1008 | const unsigned char *rngcat, | |
1009 | u32 rngcat_len) | |
1010 | { | |
1011 | u16 cat_high; | |
1012 | u16 cat_low; | |
1013 | u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1; | |
1014 | u32 iter; | |
1015 | ||
1016 | if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01) | |
1017 | return -EFAULT; | |
1018 | ||
1019 | for (iter = 0; iter < rngcat_len; iter += 4) { | |
d3e2ce3b | 1020 | cat_high = get_unaligned_be16(&rngcat[iter]); |
484b3669 | 1021 | if ((iter + 4) <= rngcat_len) |
d3e2ce3b | 1022 | cat_low = get_unaligned_be16(&rngcat[iter + 2]); |
484b3669 PM |
1023 | else |
1024 | cat_low = 0; | |
1025 | ||
1026 | if (cat_high > cat_prev) | |
1027 | return -EFAULT; | |
1028 | ||
1029 | cat_prev = cat_low; | |
1030 | } | |
1031 | ||
1032 | return 0; | |
1033 | } | |
1034 | ||
1035 | /** | |
1036 | * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network | |
1037 | * @doi_def: the DOI definition | |
1038 | * @secattr: the security attributes | |
1039 | * @net_cat: the zero'd out category list in network/CIPSO format | |
1040 | * @net_cat_len: the length of the CIPSO category list in bytes | |
1041 | * | |
1042 | * Description: | |
1043 | * Perform a label mapping to translate a local MLS category bitmap to the | |
1044 | * correct CIPSO category list using the given DOI definition. Returns the | |
1045 | * size in bytes of the network category bitmap on success, negative values | |
1046 | * otherwise. | |
1047 | * | |
1048 | */ | |
1049 | static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, | |
1050 | const struct netlbl_lsm_secattr *secattr, | |
1051 | unsigned char *net_cat, | |
1052 | u32 net_cat_len) | |
1053 | { | |
484b3669 | 1054 | int iter = -1; |
f998e8cb | 1055 | u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2]; |
484b3669 PM |
1056 | u32 array_cnt = 0; |
1057 | u32 cat_size = 0; | |
1058 | ||
f998e8cb | 1059 | /* make sure we don't overflow the 'array[]' variable */ |
128c6b6c PM |
1060 | if (net_cat_len > |
1061 | (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN)) | |
1062 | return -ENOSPC; | |
484b3669 PM |
1063 | |
1064 | for (;;) { | |
4fbe63d1 | 1065 | iter = netlbl_catmap_walk(secattr->attr.mls.cat, iter + 1); |
484b3669 PM |
1066 | if (iter < 0) |
1067 | break; | |
1068 | cat_size += (iter == 0 ? 0 : sizeof(u16)); | |
1069 | if (cat_size > net_cat_len) | |
1070 | return -ENOSPC; | |
1071 | array[array_cnt++] = iter; | |
1072 | ||
4fbe63d1 | 1073 | iter = netlbl_catmap_walkrng(secattr->attr.mls.cat, iter); |
484b3669 PM |
1074 | if (iter < 0) |
1075 | return -EFAULT; | |
1076 | cat_size += sizeof(u16); | |
1077 | if (cat_size > net_cat_len) | |
1078 | return -ENOSPC; | |
1079 | array[array_cnt++] = iter; | |
1080 | } | |
1081 | ||
1082 | for (iter = 0; array_cnt > 0;) { | |
1083 | *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]); | |
1084 | iter += 2; | |
1085 | array_cnt--; | |
1086 | if (array[array_cnt] != 0) { | |
1087 | *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]); | |
1088 | iter += 2; | |
1089 | } | |
1090 | } | |
1091 | ||
1092 | return cat_size; | |
1093 | } | |
1094 | ||
1095 | /** | |
1096 | * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host | |
1097 | * @doi_def: the DOI definition | |
1098 | * @net_cat: the category list in network/CIPSO format | |
1099 | * @net_cat_len: the length of the CIPSO bitmap in bytes | |
1100 | * @secattr: the security attributes | |
1101 | * | |
1102 | * Description: | |
1103 | * Perform a label mapping to translate a CIPSO category list to the correct | |
1104 | * local MLS category bitmap using the given DOI definition. Returns zero on | |
1105 | * success, negative values on failure. | |
1106 | * | |
1107 | */ | |
1108 | static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, | |
1109 | const unsigned char *net_cat, | |
1110 | u32 net_cat_len, | |
1111 | struct netlbl_lsm_secattr *secattr) | |
1112 | { | |
1113 | int ret_val; | |
1114 | u32 net_iter; | |
1115 | u16 cat_low; | |
1116 | u16 cat_high; | |
1117 | ||
132adf54 | 1118 | for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) { |
d3e2ce3b | 1119 | cat_high = get_unaligned_be16(&net_cat[net_iter]); |
484b3669 | 1120 | if ((net_iter + 4) <= net_cat_len) |
d3e2ce3b | 1121 | cat_low = get_unaligned_be16(&net_cat[net_iter + 2]); |
484b3669 PM |
1122 | else |
1123 | cat_low = 0; | |
1124 | ||
4fbe63d1 PM |
1125 | ret_val = netlbl_catmap_setrng(&secattr->attr.mls.cat, |
1126 | cat_low, | |
1127 | cat_high, | |
1128 | GFP_ATOMIC); | |
484b3669 PM |
1129 | if (ret_val != 0) |
1130 | return ret_val; | |
1131 | } | |
1132 | ||
1133 | return 0; | |
1134 | } | |
1135 | ||
446fda4f PM |
1136 | /* |
1137 | * Protocol Handling Functions | |
1138 | */ | |
1139 | ||
446fda4f PM |
1140 | /** |
1141 | * cipso_v4_gentag_hdr - Generate a CIPSO option header | |
1142 | * @doi_def: the DOI definition | |
91b1ed0a | 1143 | * @len: the total tag length in bytes, not including this header |
446fda4f PM |
1144 | * @buf: the CIPSO option buffer |
1145 | * | |
1146 | * Description: | |
91b1ed0a | 1147 | * Write a CIPSO header into the beginning of @buffer. |
446fda4f PM |
1148 | * |
1149 | */ | |
91b1ed0a PM |
1150 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
1151 | unsigned char *buf, | |
1152 | u32 len) | |
446fda4f | 1153 | { |
446fda4f PM |
1154 | buf[0] = IPOPT_CIPSO; |
1155 | buf[1] = CIPSO_V4_HDR_LEN + len; | |
e233febd | 1156 | put_unaligned_be32(doi_def->doi, &buf[2]); |
446fda4f PM |
1157 | } |
1158 | ||
446fda4f PM |
1159 | /** |
1160 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) | |
1161 | * @doi_def: the DOI definition | |
1162 | * @secattr: the security attributes | |
1163 | * @buffer: the option buffer | |
1164 | * @buffer_len: length of buffer in bytes | |
1165 | * | |
1166 | * Description: | |
1167 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The | |
1168 | * actual buffer length may be larger than the indicated size due to | |
91b1ed0a PM |
1169 | * translation between host and network category bitmaps. Returns the size of |
1170 | * the tag on success, negative values on failure. | |
446fda4f PM |
1171 | * |
1172 | */ | |
1173 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, | |
1174 | const struct netlbl_lsm_secattr *secattr, | |
91b1ed0a PM |
1175 | unsigned char *buffer, |
1176 | u32 buffer_len) | |
446fda4f | 1177 | { |
701a90ba | 1178 | int ret_val; |
91b1ed0a | 1179 | u32 tag_len; |
446fda4f PM |
1180 | u32 level; |
1181 | ||
701a90ba PM |
1182 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
1183 | return -EPERM; | |
1184 | ||
16efd454 PM |
1185 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1186 | secattr->attr.mls.lvl, | |
1187 | &level); | |
91b1ed0a PM |
1188 | if (ret_val != 0) |
1189 | return ret_val; | |
446fda4f | 1190 | |
91b1ed0a | 1191 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
446fda4f | 1192 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
02752760 | 1193 | secattr, |
91b1ed0a PM |
1194 | &buffer[4], |
1195 | buffer_len - 4); | |
446fda4f | 1196 | if (ret_val < 0) |
91b1ed0a | 1197 | return ret_val; |
446fda4f PM |
1198 | |
1199 | /* This will send packets using the "optimized" format when | |
25985edc | 1200 | * possible as specified in section 3.4.2.6 of the |
446fda4f | 1201 | * CIPSO draft. */ |
701a90ba | 1202 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
91b1ed0a | 1203 | tag_len = 14; |
701a90ba | 1204 | else |
91b1ed0a PM |
1205 | tag_len = 4 + ret_val; |
1206 | } else | |
1207 | tag_len = 4; | |
446fda4f | 1208 | |
15c45f7b | 1209 | buffer[0] = CIPSO_V4_TAG_RBITMAP; |
91b1ed0a PM |
1210 | buffer[1] = tag_len; |
1211 | buffer[3] = level; | |
446fda4f | 1212 | |
91b1ed0a | 1213 | return tag_len; |
446fda4f PM |
1214 | } |
1215 | ||
1216 | /** | |
1217 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag | |
1218 | * @doi_def: the DOI definition | |
1219 | * @tag: the CIPSO tag | |
1220 | * @secattr: the security attributes | |
1221 | * | |
1222 | * Description: | |
1223 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security | |
1224 | * attributes in @secattr. Return zero on success, negatives values on | |
1225 | * failure. | |
1226 | * | |
1227 | */ | |
1228 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, | |
1229 | const unsigned char *tag, | |
1230 | struct netlbl_lsm_secattr *secattr) | |
1231 | { | |
1232 | int ret_val; | |
1233 | u8 tag_len = tag[1]; | |
1234 | u32 level; | |
1235 | ||
1236 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1237 | if (ret_val != 0) | |
1238 | return ret_val; | |
16efd454 | 1239 | secattr->attr.mls.lvl = level; |
701a90ba | 1240 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
446fda4f PM |
1241 | |
1242 | if (tag_len > 4) { | |
446fda4f PM |
1243 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, |
1244 | &tag[4], | |
1245 | tag_len - 4, | |
02752760 PM |
1246 | secattr); |
1247 | if (ret_val != 0) { | |
4fbe63d1 | 1248 | netlbl_catmap_free(secattr->attr.mls.cat); |
446fda4f PM |
1249 | return ret_val; |
1250 | } | |
02752760 | 1251 | |
eead1c2e PA |
1252 | if (secattr->attr.mls.cat) |
1253 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
446fda4f PM |
1254 | } |
1255 | ||
1256 | return 0; | |
1257 | } | |
1258 | ||
654bbc2a PM |
1259 | /** |
1260 | * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) | |
1261 | * @doi_def: the DOI definition | |
1262 | * @secattr: the security attributes | |
1263 | * @buffer: the option buffer | |
1264 | * @buffer_len: length of buffer in bytes | |
1265 | * | |
1266 | * Description: | |
1267 | * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the | |
1268 | * size of the tag on success, negative values on failure. | |
1269 | * | |
1270 | */ | |
1271 | static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, | |
1272 | const struct netlbl_lsm_secattr *secattr, | |
1273 | unsigned char *buffer, | |
1274 | u32 buffer_len) | |
1275 | { | |
1276 | int ret_val; | |
1277 | u32 tag_len; | |
1278 | u32 level; | |
1279 | ||
1280 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1281 | return -EPERM; | |
1282 | ||
16efd454 PM |
1283 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1284 | secattr->attr.mls.lvl, | |
1285 | &level); | |
654bbc2a PM |
1286 | if (ret_val != 0) |
1287 | return ret_val; | |
1288 | ||
1289 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1290 | ret_val = cipso_v4_map_cat_enum_hton(doi_def, | |
1291 | secattr, | |
1292 | &buffer[4], | |
1293 | buffer_len - 4); | |
1294 | if (ret_val < 0) | |
1295 | return ret_val; | |
1296 | ||
1297 | tag_len = 4 + ret_val; | |
1298 | } else | |
1299 | tag_len = 4; | |
1300 | ||
15c45f7b | 1301 | buffer[0] = CIPSO_V4_TAG_ENUM; |
654bbc2a PM |
1302 | buffer[1] = tag_len; |
1303 | buffer[3] = level; | |
1304 | ||
1305 | return tag_len; | |
1306 | } | |
1307 | ||
1308 | /** | |
1309 | * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag | |
1310 | * @doi_def: the DOI definition | |
1311 | * @tag: the CIPSO tag | |
1312 | * @secattr: the security attributes | |
1313 | * | |
1314 | * Description: | |
1315 | * Parse a CIPSO enumerated tag (tag type #2) and return the security | |
1316 | * attributes in @secattr. Return zero on success, negatives values on | |
1317 | * failure. | |
1318 | * | |
1319 | */ | |
1320 | static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, | |
1321 | const unsigned char *tag, | |
1322 | struct netlbl_lsm_secattr *secattr) | |
1323 | { | |
1324 | int ret_val; | |
1325 | u8 tag_len = tag[1]; | |
1326 | u32 level; | |
1327 | ||
1328 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1329 | if (ret_val != 0) | |
1330 | return ret_val; | |
16efd454 | 1331 | secattr->attr.mls.lvl = level; |
654bbc2a PM |
1332 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1333 | ||
1334 | if (tag_len > 4) { | |
654bbc2a PM |
1335 | ret_val = cipso_v4_map_cat_enum_ntoh(doi_def, |
1336 | &tag[4], | |
1337 | tag_len - 4, | |
1338 | secattr); | |
1339 | if (ret_val != 0) { | |
4fbe63d1 | 1340 | netlbl_catmap_free(secattr->attr.mls.cat); |
654bbc2a PM |
1341 | return ret_val; |
1342 | } | |
1343 | ||
1344 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
1345 | } | |
1346 | ||
1347 | return 0; | |
1348 | } | |
1349 | ||
484b3669 PM |
1350 | /** |
1351 | * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) | |
1352 | * @doi_def: the DOI definition | |
1353 | * @secattr: the security attributes | |
1354 | * @buffer: the option buffer | |
1355 | * @buffer_len: length of buffer in bytes | |
1356 | * | |
1357 | * Description: | |
1358 | * Generate a CIPSO option using the ranged tag, tag type #5. Returns the | |
1359 | * size of the tag on success, negative values on failure. | |
1360 | * | |
1361 | */ | |
1362 | static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, | |
1363 | const struct netlbl_lsm_secattr *secattr, | |
1364 | unsigned char *buffer, | |
1365 | u32 buffer_len) | |
1366 | { | |
1367 | int ret_val; | |
1368 | u32 tag_len; | |
1369 | u32 level; | |
1370 | ||
1371 | if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL)) | |
1372 | return -EPERM; | |
1373 | ||
16efd454 PM |
1374 | ret_val = cipso_v4_map_lvl_hton(doi_def, |
1375 | secattr->attr.mls.lvl, | |
1376 | &level); | |
484b3669 PM |
1377 | if (ret_val != 0) |
1378 | return ret_val; | |
1379 | ||
1380 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { | |
1381 | ret_val = cipso_v4_map_cat_rng_hton(doi_def, | |
1382 | secattr, | |
1383 | &buffer[4], | |
1384 | buffer_len - 4); | |
1385 | if (ret_val < 0) | |
1386 | return ret_val; | |
1387 | ||
1388 | tag_len = 4 + ret_val; | |
1389 | } else | |
1390 | tag_len = 4; | |
1391 | ||
15c45f7b | 1392 | buffer[0] = CIPSO_V4_TAG_RANGE; |
484b3669 PM |
1393 | buffer[1] = tag_len; |
1394 | buffer[3] = level; | |
1395 | ||
1396 | return tag_len; | |
1397 | } | |
1398 | ||
1399 | /** | |
1400 | * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag | |
1401 | * @doi_def: the DOI definition | |
1402 | * @tag: the CIPSO tag | |
1403 | * @secattr: the security attributes | |
1404 | * | |
1405 | * Description: | |
1406 | * Parse a CIPSO ranged tag (tag type #5) and return the security attributes | |
1407 | * in @secattr. Return zero on success, negatives values on failure. | |
1408 | * | |
1409 | */ | |
1410 | static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, | |
1411 | const unsigned char *tag, | |
1412 | struct netlbl_lsm_secattr *secattr) | |
1413 | { | |
1414 | int ret_val; | |
1415 | u8 tag_len = tag[1]; | |
1416 | u32 level; | |
1417 | ||
1418 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); | |
1419 | if (ret_val != 0) | |
1420 | return ret_val; | |
16efd454 | 1421 | secattr->attr.mls.lvl = level; |
484b3669 PM |
1422 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
1423 | ||
1424 | if (tag_len > 4) { | |
484b3669 PM |
1425 | ret_val = cipso_v4_map_cat_rng_ntoh(doi_def, |
1426 | &tag[4], | |
1427 | tag_len - 4, | |
1428 | secattr); | |
1429 | if (ret_val != 0) { | |
4fbe63d1 | 1430 | netlbl_catmap_free(secattr->attr.mls.cat); |
484b3669 PM |
1431 | return ret_val; |
1432 | } | |
1433 | ||
eead1c2e PA |
1434 | if (secattr->attr.mls.cat) |
1435 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; | |
484b3669 PM |
1436 | } |
1437 | ||
1438 | return 0; | |
1439 | } | |
1440 | ||
15c45f7b PM |
1441 | /** |
1442 | * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard) | |
1443 | * @doi_def: the DOI definition | |
1444 | * @secattr: the security attributes | |
1445 | * @buffer: the option buffer | |
1446 | * @buffer_len: length of buffer in bytes | |
1447 | * | |
1448 | * Description: | |
1449 | * Generate a CIPSO option using the local tag. Returns the size of the tag | |
1450 | * on success, negative values on failure. | |
1451 | * | |
1452 | */ | |
1453 | static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def, | |
1454 | const struct netlbl_lsm_secattr *secattr, | |
1455 | unsigned char *buffer, | |
1456 | u32 buffer_len) | |
1457 | { | |
1458 | if (!(secattr->flags & NETLBL_SECATTR_SECID)) | |
1459 | return -EPERM; | |
1460 | ||
1461 | buffer[0] = CIPSO_V4_TAG_LOCAL; | |
1462 | buffer[1] = CIPSO_V4_TAG_LOC_BLEN; | |
1463 | *(u32 *)&buffer[2] = secattr->attr.secid; | |
1464 | ||
1465 | return CIPSO_V4_TAG_LOC_BLEN; | |
1466 | } | |
1467 | ||
1468 | /** | |
1469 | * cipso_v4_parsetag_loc - Parse a CIPSO local tag | |
1470 | * @doi_def: the DOI definition | |
1471 | * @tag: the CIPSO tag | |
1472 | * @secattr: the security attributes | |
1473 | * | |
1474 | * Description: | |
1475 | * Parse a CIPSO local tag and return the security attributes in @secattr. | |
1476 | * Return zero on success, negatives values on failure. | |
1477 | * | |
1478 | */ | |
1479 | static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def, | |
1480 | const unsigned char *tag, | |
1481 | struct netlbl_lsm_secattr *secattr) | |
1482 | { | |
1483 | secattr->attr.secid = *(u32 *)&tag[2]; | |
1484 | secattr->flags |= NETLBL_SECATTR_SECID; | |
1485 | ||
1486 | return 0; | |
1487 | } | |
1488 | ||
04f81f01 PM |
1489 | /** |
1490 | * cipso_v4_optptr - Find the CIPSO option in the packet | |
1491 | * @skb: the packet | |
1492 | * | |
1493 | * Description: | |
1494 | * Parse the packet's IP header looking for a CIPSO option. Returns a pointer | |
076ed3da | 1495 | * to the start of the CIPSO option on success, NULL if one is not found. |
04f81f01 PM |
1496 | * |
1497 | */ | |
1498 | unsigned char *cipso_v4_optptr(const struct sk_buff *skb) | |
1499 | { | |
1500 | const struct iphdr *iph = ip_hdr(skb); | |
1501 | unsigned char *optptr = (unsigned char *)&(ip_hdr(skb)[1]); | |
1502 | int optlen; | |
1503 | int taglen; | |
1504 | ||
076ed3da | 1505 | for (optlen = iph->ihl*4 - sizeof(struct iphdr); optlen > 1; ) { |
40413955 | 1506 | switch (optptr[0]) { |
40413955 | 1507 | case IPOPT_END: |
1508 | return NULL; | |
1509 | case IPOPT_NOOP: | |
1510 | taglen = 1; | |
1511 | break; | |
1512 | default: | |
1513 | taglen = optptr[1]; | |
1514 | } | |
076ed3da SN |
1515 | if (!taglen || taglen > optlen) |
1516 | return NULL; | |
1517 | if (optptr[0] == IPOPT_CIPSO) | |
1518 | return optptr; | |
1519 | ||
04f81f01 PM |
1520 | optlen -= taglen; |
1521 | optptr += taglen; | |
1522 | } | |
1523 | ||
1524 | return NULL; | |
1525 | } | |
1526 | ||
446fda4f PM |
1527 | /** |
1528 | * cipso_v4_validate - Validate a CIPSO option | |
3628e3cb | 1529 | * @skb: the packet |
446fda4f PM |
1530 | * @option: the start of the option, on error it is set to point to the error |
1531 | * | |
1532 | * Description: | |
1533 | * This routine is called to validate a CIPSO option, it checks all of the | |
1534 | * fields to ensure that they are at least valid, see the draft snippet below | |
1535 | * for details. If the option is valid then a zero value is returned and | |
1536 | * the value of @option is unchanged. If the option is invalid then a | |
1537 | * non-zero value is returned and @option is adjusted to point to the | |
1538 | * offending portion of the option. From the IETF draft ... | |
1539 | * | |
1540 | * "If any field within the CIPSO options, such as the DOI identifier, is not | |
1541 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' | |
1542 | * (type 12) is generated and returned. The ICMP code field is set to 'bad | |
1543 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field | |
1544 | * that is unrecognized." | |
1545 | * | |
1546 | */ | |
15c45f7b | 1547 | int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) |
446fda4f PM |
1548 | { |
1549 | unsigned char *opt = *option; | |
1550 | unsigned char *tag; | |
1551 | unsigned char opt_iter; | |
1552 | unsigned char err_offset = 0; | |
1553 | u8 opt_len; | |
1554 | u8 tag_len; | |
1555 | struct cipso_v4_doi *doi_def = NULL; | |
1556 | u32 tag_iter; | |
1557 | ||
1558 | /* caller already checks for length values that are too large */ | |
1559 | opt_len = opt[1]; | |
1560 | if (opt_len < 8) { | |
1561 | err_offset = 1; | |
1562 | goto validate_return; | |
1563 | } | |
1564 | ||
1565 | rcu_read_lock(); | |
d3e2ce3b | 1566 | doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2])); |
51456b29 | 1567 | if (!doi_def) { |
446fda4f PM |
1568 | err_offset = 2; |
1569 | goto validate_return_locked; | |
1570 | } | |
1571 | ||
15c45f7b | 1572 | opt_iter = CIPSO_V4_HDR_LEN; |
446fda4f PM |
1573 | tag = opt + opt_iter; |
1574 | while (opt_iter < opt_len) { | |
1575 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) | |
1576 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || | |
1577 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { | |
1578 | err_offset = opt_iter; | |
1579 | goto validate_return_locked; | |
1580 | } | |
1581 | ||
d71b7896 ED |
1582 | if (opt_iter + 1 == opt_len) { |
1583 | err_offset = opt_iter; | |
1584 | goto validate_return_locked; | |
1585 | } | |
446fda4f PM |
1586 | tag_len = tag[1]; |
1587 | if (tag_len > (opt_len - opt_iter)) { | |
1588 | err_offset = opt_iter + 1; | |
1589 | goto validate_return_locked; | |
1590 | } | |
1591 | ||
1592 | switch (tag[0]) { | |
1593 | case CIPSO_V4_TAG_RBITMAP: | |
15c45f7b | 1594 | if (tag_len < CIPSO_V4_TAG_RBM_BLEN) { |
446fda4f PM |
1595 | err_offset = opt_iter + 1; |
1596 | goto validate_return_locked; | |
1597 | } | |
1598 | ||
1599 | /* We are already going to do all the verification | |
1600 | * necessary at the socket layer so from our point of | |
1601 | * view it is safe to turn these checks off (and less | |
1602 | * work), however, the CIPSO draft says we should do | |
1603 | * all the CIPSO validations here but it doesn't | |
1604 | * really specify _exactly_ what we need to validate | |
1605 | * ... so, just make it a sysctl tunable. */ | |
1606 | if (cipso_v4_rbm_strictvalid) { | |
1607 | if (cipso_v4_map_lvl_valid(doi_def, | |
1608 | tag[3]) < 0) { | |
1609 | err_offset = opt_iter + 3; | |
1610 | goto validate_return_locked; | |
1611 | } | |
15c45f7b | 1612 | if (tag_len > CIPSO_V4_TAG_RBM_BLEN && |
446fda4f PM |
1613 | cipso_v4_map_cat_rbm_valid(doi_def, |
1614 | &tag[4], | |
1615 | tag_len - 4) < 0) { | |
1616 | err_offset = opt_iter + 4; | |
1617 | goto validate_return_locked; | |
1618 | } | |
1619 | } | |
1620 | break; | |
654bbc2a | 1621 | case CIPSO_V4_TAG_ENUM: |
15c45f7b | 1622 | if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) { |
654bbc2a PM |
1623 | err_offset = opt_iter + 1; |
1624 | goto validate_return_locked; | |
1625 | } | |
1626 | ||
1627 | if (cipso_v4_map_lvl_valid(doi_def, | |
1628 | tag[3]) < 0) { | |
1629 | err_offset = opt_iter + 3; | |
1630 | goto validate_return_locked; | |
1631 | } | |
15c45f7b | 1632 | if (tag_len > CIPSO_V4_TAG_ENUM_BLEN && |
654bbc2a PM |
1633 | cipso_v4_map_cat_enum_valid(doi_def, |
1634 | &tag[4], | |
1635 | tag_len - 4) < 0) { | |
1636 | err_offset = opt_iter + 4; | |
1637 | goto validate_return_locked; | |
1638 | } | |
1639 | break; | |
484b3669 | 1640 | case CIPSO_V4_TAG_RANGE: |
15c45f7b | 1641 | if (tag_len < CIPSO_V4_TAG_RNG_BLEN) { |
484b3669 PM |
1642 | err_offset = opt_iter + 1; |
1643 | goto validate_return_locked; | |
1644 | } | |
1645 | ||
1646 | if (cipso_v4_map_lvl_valid(doi_def, | |
1647 | tag[3]) < 0) { | |
1648 | err_offset = opt_iter + 3; | |
1649 | goto validate_return_locked; | |
1650 | } | |
15c45f7b | 1651 | if (tag_len > CIPSO_V4_TAG_RNG_BLEN && |
484b3669 PM |
1652 | cipso_v4_map_cat_rng_valid(doi_def, |
1653 | &tag[4], | |
1654 | tag_len - 4) < 0) { | |
1655 | err_offset = opt_iter + 4; | |
1656 | goto validate_return_locked; | |
1657 | } | |
1658 | break; | |
15c45f7b PM |
1659 | case CIPSO_V4_TAG_LOCAL: |
1660 | /* This is a non-standard tag that we only allow for | |
1661 | * local connections, so if the incoming interface is | |
89d7ae34 PM |
1662 | * not the loopback device drop the packet. Further, |
1663 | * there is no legitimate reason for setting this from | |
1664 | * userspace so reject it if skb is NULL. */ | |
51456b29 | 1665 | if (!skb || !(skb->dev->flags & IFF_LOOPBACK)) { |
15c45f7b PM |
1666 | err_offset = opt_iter; |
1667 | goto validate_return_locked; | |
1668 | } | |
1669 | if (tag_len != CIPSO_V4_TAG_LOC_BLEN) { | |
1670 | err_offset = opt_iter + 1; | |
1671 | goto validate_return_locked; | |
1672 | } | |
1673 | break; | |
446fda4f PM |
1674 | default: |
1675 | err_offset = opt_iter; | |
1676 | goto validate_return_locked; | |
1677 | } | |
1678 | ||
1679 | tag += tag_len; | |
1680 | opt_iter += tag_len; | |
1681 | } | |
1682 | ||
1683 | validate_return_locked: | |
1684 | rcu_read_unlock(); | |
1685 | validate_return: | |
1686 | *option = opt + err_offset; | |
1687 | return err_offset; | |
1688 | } | |
1689 | ||
1690 | /** | |
25985edc | 1691 | * cipso_v4_error - Send the correct response for a bad packet |
446fda4f PM |
1692 | * @skb: the packet |
1693 | * @error: the error code | |
1694 | * @gateway: CIPSO gateway flag | |
1695 | * | |
1696 | * Description: | |
1697 | * Based on the error code given in @error, send an ICMP error message back to | |
1698 | * the originating host. From the IETF draft ... | |
1699 | * | |
1700 | * "If the contents of the CIPSO [option] are valid but the security label is | |
1701 | * outside of the configured host or port label range, the datagram is | |
1702 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and | |
1703 | * returned. The code field of the ICMP is set to 'communication with | |
1704 | * destination network administratively prohibited' (code 9) or to | |
1705 | * 'communication with destination host administratively prohibited' | |
1706 | * (code 10). The value of the code is dependent on whether the originator | |
1707 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The | |
1708 | * recipient of the ICMP message MUST be able to handle either value. The | |
1709 | * same procedure is performed if a CIPSO [option] can not be added to an | |
1710 | * IP packet because it is too large to fit in the IP options area." | |
1711 | * | |
1712 | * "If the error is triggered by receipt of an ICMP message, the message is | |
1713 | * discarded and no response is permitted (consistent with general ICMP | |
1714 | * processing rules)." | |
1715 | * | |
1716 | */ | |
1717 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) | |
1718 | { | |
3da1ed7a NS |
1719 | unsigned char optbuf[sizeof(struct ip_options) + 40]; |
1720 | struct ip_options *opt = (struct ip_options *)optbuf; | |
3e72dfdf | 1721 | int res; |
3da1ed7a | 1722 | |
eddc9ec5 | 1723 | if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) |
446fda4f PM |
1724 | return; |
1725 | ||
3da1ed7a NS |
1726 | /* |
1727 | * We might be called above the IP layer, | |
1728 | * so we can not use icmp_send and IPCB here. | |
1729 | */ | |
1730 | ||
1731 | memset(opt, 0, sizeof(struct ip_options)); | |
1732 | opt->optlen = ip_hdr(skb)->ihl*4 - sizeof(struct iphdr); | |
3e72dfdf MC |
1733 | rcu_read_lock(); |
1734 | res = __ip_options_compile(dev_net(skb->dev), opt, skb, NULL); | |
1735 | rcu_read_unlock(); | |
1736 | ||
1737 | if (res) | |
3da1ed7a NS |
1738 | return; |
1739 | ||
446fda4f | 1740 | if (gateway) |
3da1ed7a | 1741 | __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0, opt); |
446fda4f | 1742 | else |
3da1ed7a | 1743 | __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0, opt); |
446fda4f PM |
1744 | } |
1745 | ||
1746 | /** | |
948bf85c PM |
1747 | * cipso_v4_genopt - Generate a CIPSO option |
1748 | * @buf: the option buffer | |
1749 | * @buf_len: the size of opt_buf | |
446fda4f | 1750 | * @doi_def: the CIPSO DOI to use |
948bf85c | 1751 | * @secattr: the security attributes |
446fda4f PM |
1752 | * |
1753 | * Description: | |
948bf85c PM |
1754 | * Generate a CIPSO option using the DOI definition and security attributes |
1755 | * passed to the function. Returns the length of the option on success and | |
1756 | * negative values on failure. | |
446fda4f PM |
1757 | * |
1758 | */ | |
948bf85c PM |
1759 | static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, |
1760 | const struct cipso_v4_doi *doi_def, | |
1761 | const struct netlbl_lsm_secattr *secattr) | |
446fda4f | 1762 | { |
948bf85c | 1763 | int ret_val; |
446fda4f | 1764 | u32 iter; |
446fda4f | 1765 | |
948bf85c PM |
1766 | if (buf_len <= CIPSO_V4_HDR_LEN) |
1767 | return -ENOSPC; | |
91b1ed0a | 1768 | |
446fda4f PM |
1769 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
1770 | * really a good assumption to make but since we only support the MAC | |
1771 | * tags right now it is a safe assumption. */ | |
1772 | iter = 0; | |
1773 | do { | |
91b1ed0a | 1774 | memset(buf, 0, buf_len); |
446fda4f PM |
1775 | switch (doi_def->tags[iter]) { |
1776 | case CIPSO_V4_TAG_RBITMAP: | |
1777 | ret_val = cipso_v4_gentag_rbm(doi_def, | |
91b1ed0a PM |
1778 | secattr, |
1779 | &buf[CIPSO_V4_HDR_LEN], | |
1780 | buf_len - CIPSO_V4_HDR_LEN); | |
446fda4f | 1781 | break; |
654bbc2a PM |
1782 | case CIPSO_V4_TAG_ENUM: |
1783 | ret_val = cipso_v4_gentag_enum(doi_def, | |
1784 | secattr, | |
1785 | &buf[CIPSO_V4_HDR_LEN], | |
1786 | buf_len - CIPSO_V4_HDR_LEN); | |
1787 | break; | |
484b3669 PM |
1788 | case CIPSO_V4_TAG_RANGE: |
1789 | ret_val = cipso_v4_gentag_rng(doi_def, | |
1790 | secattr, | |
1791 | &buf[CIPSO_V4_HDR_LEN], | |
1792 | buf_len - CIPSO_V4_HDR_LEN); | |
1793 | break; | |
15c45f7b PM |
1794 | case CIPSO_V4_TAG_LOCAL: |
1795 | ret_val = cipso_v4_gentag_loc(doi_def, | |
1796 | secattr, | |
1797 | &buf[CIPSO_V4_HDR_LEN], | |
1798 | buf_len - CIPSO_V4_HDR_LEN); | |
1799 | break; | |
446fda4f | 1800 | default: |
948bf85c | 1801 | return -EPERM; |
446fda4f PM |
1802 | } |
1803 | ||
1804 | iter++; | |
91b1ed0a | 1805 | } while (ret_val < 0 && |
446fda4f PM |
1806 | iter < CIPSO_V4_TAG_MAXCNT && |
1807 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); | |
91b1ed0a | 1808 | if (ret_val < 0) |
948bf85c | 1809 | return ret_val; |
91b1ed0a | 1810 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
948bf85c PM |
1811 | return CIPSO_V4_HDR_LEN + ret_val; |
1812 | } | |
1813 | ||
1814 | /** | |
1815 | * cipso_v4_sock_setattr - Add a CIPSO option to a socket | |
1816 | * @sk: the socket | |
1817 | * @doi_def: the CIPSO DOI to use | |
1818 | * @secattr: the specific security attributes of the socket | |
1819 | * | |
1820 | * Description: | |
1821 | * Set the CIPSO option on the given socket using the DOI definition and | |
1822 | * security attributes passed to the function. This function requires | |
1823 | * exclusive access to @sk, which means it either needs to be in the | |
1824 | * process of being created or locked. Returns zero on success and negative | |
1825 | * values on failure. | |
1826 | * | |
1827 | */ | |
1828 | int cipso_v4_sock_setattr(struct sock *sk, | |
1829 | const struct cipso_v4_doi *doi_def, | |
1830 | const struct netlbl_lsm_secattr *secattr) | |
1831 | { | |
1832 | int ret_val = -EPERM; | |
1833 | unsigned char *buf = NULL; | |
1834 | u32 buf_len; | |
1835 | u32 opt_len; | |
f6d8bd05 | 1836 | struct ip_options_rcu *old, *opt = NULL; |
948bf85c PM |
1837 | struct inet_sock *sk_inet; |
1838 | struct inet_connection_sock *sk_conn; | |
1839 | ||
1840 | /* In the case of sock_create_lite(), the sock->sk field is not | |
1841 | * defined yet but it is not a problem as the only users of these | |
1842 | * "lite" PF_INET sockets are functions which do an accept() call | |
1843 | * afterwards so we will label the socket as part of the accept(). */ | |
51456b29 | 1844 | if (!sk) |
948bf85c PM |
1845 | return 0; |
1846 | ||
1847 | /* We allocate the maximum CIPSO option size here so we are probably | |
1848 | * being a little wasteful, but it makes our life _much_ easier later | |
1849 | * on and after all we are only talking about 40 bytes. */ | |
1850 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1851 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
51456b29 | 1852 | if (!buf) { |
948bf85c PM |
1853 | ret_val = -ENOMEM; |
1854 | goto socket_setattr_failure; | |
1855 | } | |
1856 | ||
1857 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1858 | if (ret_val < 0) | |
1859 | goto socket_setattr_failure; | |
1860 | buf_len = ret_val; | |
446fda4f PM |
1861 | |
1862 | /* We can't use ip_options_get() directly because it makes a call to | |
1863 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
f8687afe PM |
1864 | * we won't always have CAP_NET_RAW even though we _always_ want to |
1865 | * set the IPOPT_CIPSO option. */ | |
446fda4f PM |
1866 | opt_len = (buf_len + 3) & ~3; |
1867 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
51456b29 | 1868 | if (!opt) { |
446fda4f PM |
1869 | ret_val = -ENOMEM; |
1870 | goto socket_setattr_failure; | |
1871 | } | |
f6d8bd05 ED |
1872 | memcpy(opt->opt.__data, buf, buf_len); |
1873 | opt->opt.optlen = opt_len; | |
1874 | opt->opt.cipso = sizeof(struct iphdr); | |
446fda4f PM |
1875 | kfree(buf); |
1876 | buf = NULL; | |
446fda4f PM |
1877 | |
1878 | sk_inet = inet_sk(sk); | |
f6d8bd05 | 1879 | |
1e1d04e6 HFS |
1880 | old = rcu_dereference_protected(sk_inet->inet_opt, |
1881 | lockdep_sock_is_held(sk)); | |
446fda4f PM |
1882 | if (sk_inet->is_icsk) { |
1883 | sk_conn = inet_csk(sk); | |
f6d8bd05 ED |
1884 | if (old) |
1885 | sk_conn->icsk_ext_hdr_len -= old->opt.optlen; | |
1886 | sk_conn->icsk_ext_hdr_len += opt->opt.optlen; | |
446fda4f PM |
1887 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); |
1888 | } | |
f6d8bd05 ED |
1889 | rcu_assign_pointer(sk_inet->inet_opt, opt); |
1890 | if (old) | |
4f9c8c1b | 1891 | kfree_rcu(old, rcu); |
446fda4f PM |
1892 | |
1893 | return 0; | |
1894 | ||
1895 | socket_setattr_failure: | |
1896 | kfree(buf); | |
1897 | kfree(opt); | |
1898 | return ret_val; | |
1899 | } | |
1900 | ||
014ab19a | 1901 | /** |
389fb800 PM |
1902 | * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket |
1903 | * @req: the connection request socket | |
1904 | * @doi_def: the CIPSO DOI to use | |
1905 | * @secattr: the specific security attributes of the socket | |
014ab19a PM |
1906 | * |
1907 | * Description: | |
389fb800 PM |
1908 | * Set the CIPSO option on the given socket using the DOI definition and |
1909 | * security attributes passed to the function. Returns zero on success and | |
1910 | * negative values on failure. | |
014ab19a PM |
1911 | * |
1912 | */ | |
389fb800 PM |
1913 | int cipso_v4_req_setattr(struct request_sock *req, |
1914 | const struct cipso_v4_doi *doi_def, | |
1915 | const struct netlbl_lsm_secattr *secattr) | |
014ab19a | 1916 | { |
389fb800 PM |
1917 | int ret_val = -EPERM; |
1918 | unsigned char *buf = NULL; | |
1919 | u32 buf_len; | |
1920 | u32 opt_len; | |
f6d8bd05 | 1921 | struct ip_options_rcu *opt = NULL; |
389fb800 | 1922 | struct inet_request_sock *req_inet; |
014ab19a | 1923 | |
389fb800 PM |
1924 | /* We allocate the maximum CIPSO option size here so we are probably |
1925 | * being a little wasteful, but it makes our life _much_ easier later | |
1926 | * on and after all we are only talking about 40 bytes. */ | |
1927 | buf_len = CIPSO_V4_OPT_LEN_MAX; | |
1928 | buf = kmalloc(buf_len, GFP_ATOMIC); | |
51456b29 | 1929 | if (!buf) { |
389fb800 PM |
1930 | ret_val = -ENOMEM; |
1931 | goto req_setattr_failure; | |
1932 | } | |
1933 | ||
1934 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); | |
1935 | if (ret_val < 0) | |
1936 | goto req_setattr_failure; | |
1937 | buf_len = ret_val; | |
1938 | ||
1939 | /* We can't use ip_options_get() directly because it makes a call to | |
1940 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and | |
1941 | * we won't always have CAP_NET_RAW even though we _always_ want to | |
1942 | * set the IPOPT_CIPSO option. */ | |
1943 | opt_len = (buf_len + 3) & ~3; | |
1944 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); | |
51456b29 | 1945 | if (!opt) { |
389fb800 PM |
1946 | ret_val = -ENOMEM; |
1947 | goto req_setattr_failure; | |
1948 | } | |
f6d8bd05 ED |
1949 | memcpy(opt->opt.__data, buf, buf_len); |
1950 | opt->opt.optlen = opt_len; | |
1951 | opt->opt.cipso = sizeof(struct iphdr); | |
389fb800 PM |
1952 | kfree(buf); |
1953 | buf = NULL; | |
1954 | ||
1955 | req_inet = inet_rsk(req); | |
c92e8c02 | 1956 | opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt); |
f6d8bd05 | 1957 | if (opt) |
4f9c8c1b | 1958 | kfree_rcu(opt, rcu); |
389fb800 PM |
1959 | |
1960 | return 0; | |
1961 | ||
1962 | req_setattr_failure: | |
1963 | kfree(buf); | |
1964 | kfree(opt); | |
1965 | return ret_val; | |
1966 | } | |
1967 | ||
1968 | /** | |
1969 | * cipso_v4_delopt - Delete the CIPSO option from a set of IP options | |
1970 | * @opt_ptr: IP option pointer | |
1971 | * | |
1972 | * Description: | |
1973 | * Deletes the CIPSO IP option from a set of IP options and makes the necessary | |
1974 | * adjustments to the IP option structure. Returns zero on success, negative | |
1975 | * values on failure. | |
1976 | * | |
1977 | */ | |
c92e8c02 | 1978 | static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr) |
389fb800 | 1979 | { |
c92e8c02 | 1980 | struct ip_options_rcu *opt = rcu_dereference_protected(*opt_ptr, 1); |
389fb800 | 1981 | int hdr_delta = 0; |
014ab19a | 1982 | |
c92e8c02 ED |
1983 | if (!opt || opt->opt.cipso == 0) |
1984 | return 0; | |
f6d8bd05 | 1985 | if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) { |
014ab19a PM |
1986 | u8 cipso_len; |
1987 | u8 cipso_off; | |
1988 | unsigned char *cipso_ptr; | |
1989 | int iter; | |
1990 | int optlen_new; | |
1991 | ||
f6d8bd05 ED |
1992 | cipso_off = opt->opt.cipso - sizeof(struct iphdr); |
1993 | cipso_ptr = &opt->opt.__data[cipso_off]; | |
014ab19a PM |
1994 | cipso_len = cipso_ptr[1]; |
1995 | ||
f6d8bd05 ED |
1996 | if (opt->opt.srr > opt->opt.cipso) |
1997 | opt->opt.srr -= cipso_len; | |
1998 | if (opt->opt.rr > opt->opt.cipso) | |
1999 | opt->opt.rr -= cipso_len; | |
2000 | if (opt->opt.ts > opt->opt.cipso) | |
2001 | opt->opt.ts -= cipso_len; | |
2002 | if (opt->opt.router_alert > opt->opt.cipso) | |
2003 | opt->opt.router_alert -= cipso_len; | |
2004 | opt->opt.cipso = 0; | |
014ab19a PM |
2005 | |
2006 | memmove(cipso_ptr, cipso_ptr + cipso_len, | |
f6d8bd05 | 2007 | opt->opt.optlen - cipso_off - cipso_len); |
014ab19a PM |
2008 | |
2009 | /* determining the new total option length is tricky because of | |
2010 | * the padding necessary, the only thing i can think to do at | |
2011 | * this point is walk the options one-by-one, skipping the | |
2012 | * padding at the end to determine the actual option size and | |
2013 | * from there we can determine the new total option length */ | |
2014 | iter = 0; | |
2015 | optlen_new = 0; | |
f6d8bd05 ED |
2016 | while (iter < opt->opt.optlen) |
2017 | if (opt->opt.__data[iter] != IPOPT_NOP) { | |
2018 | iter += opt->opt.__data[iter + 1]; | |
014ab19a PM |
2019 | optlen_new = iter; |
2020 | } else | |
2021 | iter++; | |
f6d8bd05 ED |
2022 | hdr_delta = opt->opt.optlen; |
2023 | opt->opt.optlen = (optlen_new + 3) & ~3; | |
2024 | hdr_delta -= opt->opt.optlen; | |
014ab19a PM |
2025 | } else { |
2026 | /* only the cipso option was present on the socket so we can | |
2027 | * remove the entire option struct */ | |
389fb800 | 2028 | *opt_ptr = NULL; |
f6d8bd05 | 2029 | hdr_delta = opt->opt.optlen; |
4f9c8c1b | 2030 | kfree_rcu(opt, rcu); |
014ab19a PM |
2031 | } |
2032 | ||
389fb800 PM |
2033 | return hdr_delta; |
2034 | } | |
2035 | ||
2036 | /** | |
2037 | * cipso_v4_sock_delattr - Delete the CIPSO option from a socket | |
2038 | * @sk: the socket | |
2039 | * | |
2040 | * Description: | |
2041 | * Removes the CIPSO option from a socket, if present. | |
2042 | * | |
2043 | */ | |
2044 | void cipso_v4_sock_delattr(struct sock *sk) | |
2045 | { | |
389fb800 | 2046 | struct inet_sock *sk_inet; |
c92e8c02 | 2047 | int hdr_delta; |
389fb800 PM |
2048 | |
2049 | sk_inet = inet_sk(sk); | |
389fb800 | 2050 | |
f6d8bd05 | 2051 | hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt); |
014ab19a PM |
2052 | if (sk_inet->is_icsk && hdr_delta > 0) { |
2053 | struct inet_connection_sock *sk_conn = inet_csk(sk); | |
2054 | sk_conn->icsk_ext_hdr_len -= hdr_delta; | |
2055 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); | |
2056 | } | |
2057 | } | |
2058 | ||
389fb800 PM |
2059 | /** |
2060 | * cipso_v4_req_delattr - Delete the CIPSO option from a request socket | |
3628e3cb | 2061 | * @req: the request socket |
389fb800 PM |
2062 | * |
2063 | * Description: | |
2064 | * Removes the CIPSO option from a request socket, if present. | |
2065 | * | |
2066 | */ | |
2067 | void cipso_v4_req_delattr(struct request_sock *req) | |
2068 | { | |
c92e8c02 | 2069 | cipso_v4_delopt(&inet_rsk(req)->ireq_opt); |
389fb800 PM |
2070 | } |
2071 | ||
446fda4f | 2072 | /** |
63d804ea PM |
2073 | * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions |
2074 | * @cipso: the CIPSO v4 option | |
446fda4f PM |
2075 | * @secattr: the security attributes |
2076 | * | |
2077 | * Description: | |
63d804ea PM |
2078 | * Inspect @cipso and return the security attributes in @secattr. Returns zero |
2079 | * on success and negative values on failure. | |
446fda4f PM |
2080 | * |
2081 | */ | |
04f81f01 PM |
2082 | int cipso_v4_getattr(const unsigned char *cipso, |
2083 | struct netlbl_lsm_secattr *secattr) | |
446fda4f PM |
2084 | { |
2085 | int ret_val = -ENOMSG; | |
446fda4f PM |
2086 | u32 doi; |
2087 | struct cipso_v4_doi *doi_def; | |
2088 | ||
63d804ea PM |
2089 | if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0) |
2090 | return 0; | |
446fda4f | 2091 | |
d3e2ce3b | 2092 | doi = get_unaligned_be32(&cipso[2]); |
446fda4f | 2093 | rcu_read_lock(); |
9bb5fd2b | 2094 | doi_def = cipso_v4_doi_search(doi); |
51456b29 | 2095 | if (!doi_def) |
63d804ea | 2096 | goto getattr_return; |
91b1ed0a PM |
2097 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
2098 | * really a good assumption to make but since we only support the MAC | |
2099 | * tags right now it is a safe assumption. */ | |
63d804ea | 2100 | switch (cipso[6]) { |
446fda4f | 2101 | case CIPSO_V4_TAG_RBITMAP: |
63d804ea | 2102 | ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr); |
446fda4f | 2103 | break; |
654bbc2a | 2104 | case CIPSO_V4_TAG_ENUM: |
63d804ea | 2105 | ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr); |
654bbc2a | 2106 | break; |
484b3669 | 2107 | case CIPSO_V4_TAG_RANGE: |
63d804ea | 2108 | ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr); |
484b3669 | 2109 | break; |
15c45f7b PM |
2110 | case CIPSO_V4_TAG_LOCAL: |
2111 | ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr); | |
2112 | break; | |
446fda4f | 2113 | } |
16efd454 PM |
2114 | if (ret_val == 0) |
2115 | secattr->type = NETLBL_NLTYPE_CIPSOV4; | |
446fda4f | 2116 | |
63d804ea PM |
2117 | getattr_return: |
2118 | rcu_read_unlock(); | |
14a72f53 PM |
2119 | return ret_val; |
2120 | } | |
2121 | ||
63d804ea PM |
2122 | /** |
2123 | * cipso_v4_sock_getattr - Get the security attributes from a sock | |
2124 | * @sk: the sock | |
2125 | * @secattr: the security attributes | |
2126 | * | |
2127 | * Description: | |
2128 | * Query @sk to see if there is a CIPSO option attached to the sock and if | |
2129 | * there is return the CIPSO security attributes in @secattr. This function | |
2130 | * requires that @sk be locked, or privately held, but it does not do any | |
2131 | * locking itself. Returns zero on success and negative values on failure. | |
2132 | * | |
2133 | */ | |
2134 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) | |
2135 | { | |
f6d8bd05 ED |
2136 | struct ip_options_rcu *opt; |
2137 | int res = -ENOMSG; | |
63d804ea | 2138 | |
f6d8bd05 ED |
2139 | rcu_read_lock(); |
2140 | opt = rcu_dereference(inet_sk(sk)->inet_opt); | |
2141 | if (opt && opt->opt.cipso) | |
2142 | res = cipso_v4_getattr(opt->opt.__data + | |
2143 | opt->opt.cipso - | |
2144 | sizeof(struct iphdr), | |
2145 | secattr); | |
2146 | rcu_read_unlock(); | |
2147 | return res; | |
63d804ea PM |
2148 | } |
2149 | ||
948bf85c PM |
2150 | /** |
2151 | * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet | |
2152 | * @skb: the packet | |
3628e3cb | 2153 | * @doi_def: the DOI structure |
948bf85c PM |
2154 | * @secattr: the security attributes |
2155 | * | |
2156 | * Description: | |
2157 | * Set the CIPSO option on the given packet based on the security attributes. | |
2158 | * Returns a pointer to the IP header on success and NULL on failure. | |
2159 | * | |
2160 | */ | |
2161 | int cipso_v4_skbuff_setattr(struct sk_buff *skb, | |
2162 | const struct cipso_v4_doi *doi_def, | |
2163 | const struct netlbl_lsm_secattr *secattr) | |
2164 | { | |
2165 | int ret_val; | |
2166 | struct iphdr *iph; | |
2167 | struct ip_options *opt = &IPCB(skb)->opt; | |
2168 | unsigned char buf[CIPSO_V4_OPT_LEN_MAX]; | |
2169 | u32 buf_len = CIPSO_V4_OPT_LEN_MAX; | |
2170 | u32 opt_len; | |
2171 | int len_delta; | |
2172 | ||
00af5c69 | 2173 | ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); |
2174 | if (ret_val < 0) | |
2175 | return ret_val; | |
2176 | buf_len = ret_val; | |
948bf85c PM |
2177 | opt_len = (buf_len + 3) & ~3; |
2178 | ||
2179 | /* we overwrite any existing options to ensure that we have enough | |
2180 | * room for the CIPSO option, the reason is that we _need_ to guarantee | |
2181 | * that the security label is applied to the packet - we do the same | |
2182 | * thing when using the socket options and it hasn't caused a problem, | |
2183 | * if we need to we can always revisit this choice later */ | |
2184 | ||
2185 | len_delta = opt_len - opt->optlen; | |
2186 | /* if we don't ensure enough headroom we could panic on the skb_push() | |
2187 | * call below so make sure we have enough, we are also "mangling" the | |
2188 | * packet so we should probably do a copy-on-write call anyway */ | |
2189 | ret_val = skb_cow(skb, skb_headroom(skb) + len_delta); | |
2190 | if (ret_val < 0) | |
2191 | return ret_val; | |
2192 | ||
2193 | if (len_delta > 0) { | |
2194 | /* we assume that the header + opt->optlen have already been | |
2195 | * "pushed" in ip_options_build() or similar */ | |
2196 | iph = ip_hdr(skb); | |
2197 | skb_push(skb, len_delta); | |
2198 | memmove((char *)iph - len_delta, iph, iph->ihl << 2); | |
2199 | skb_reset_network_header(skb); | |
2200 | iph = ip_hdr(skb); | |
2201 | } else if (len_delta < 0) { | |
2202 | iph = ip_hdr(skb); | |
2203 | memset(iph + 1, IPOPT_NOP, opt->optlen); | |
2204 | } else | |
2205 | iph = ip_hdr(skb); | |
2206 | ||
2207 | if (opt->optlen > 0) | |
2208 | memset(opt, 0, sizeof(*opt)); | |
2209 | opt->optlen = opt_len; | |
2210 | opt->cipso = sizeof(struct iphdr); | |
2211 | opt->is_changed = 1; | |
2212 | ||
2213 | /* we have to do the following because we are being called from a | |
2214 | * netfilter hook which means the packet already has had the header | |
2215 | * fields populated and the checksum calculated - yes this means we | |
2216 | * are doing more work than needed but we do it to keep the core | |
2217 | * stack clean and tidy */ | |
2218 | memcpy(iph + 1, buf, buf_len); | |
2219 | if (opt_len > buf_len) | |
2220 | memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); | |
2221 | if (len_delta != 0) { | |
2222 | iph->ihl = 5 + (opt_len >> 2); | |
2223 | iph->tot_len = htons(skb->len); | |
2224 | } | |
2225 | ip_send_check(iph); | |
2226 | ||
2227 | return 0; | |
2228 | } | |
2229 | ||
2230 | /** | |
2231 | * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet | |
2232 | * @skb: the packet | |
2233 | * | |
2234 | * Description: | |
2235 | * Removes any and all CIPSO options from the given packet. Returns zero on | |
2236 | * success, negative values on failure. | |
2237 | * | |
2238 | */ | |
2239 | int cipso_v4_skbuff_delattr(struct sk_buff *skb) | |
2240 | { | |
2241 | int ret_val; | |
2242 | struct iphdr *iph; | |
2243 | struct ip_options *opt = &IPCB(skb)->opt; | |
2244 | unsigned char *cipso_ptr; | |
2245 | ||
2246 | if (opt->cipso == 0) | |
2247 | return 0; | |
2248 | ||
2249 | /* since we are changing the packet we should make a copy */ | |
2250 | ret_val = skb_cow(skb, skb_headroom(skb)); | |
2251 | if (ret_val < 0) | |
2252 | return ret_val; | |
2253 | ||
2254 | /* the easiest thing to do is just replace the cipso option with noop | |
2255 | * options since we don't change the size of the packet, although we | |
2256 | * still need to recalculate the checksum */ | |
2257 | ||
2258 | iph = ip_hdr(skb); | |
2259 | cipso_ptr = (unsigned char *)iph + opt->cipso; | |
2260 | memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); | |
2261 | opt->cipso = 0; | |
2262 | opt->is_changed = 1; | |
2263 | ||
2264 | ip_send_check(iph); | |
2265 | ||
2266 | return 0; | |
2267 | } | |
2268 | ||
446fda4f PM |
2269 | /* |
2270 | * Setup Functions | |
2271 | */ | |
2272 | ||
2273 | /** | |
2274 | * cipso_v4_init - Initialize the CIPSO module | |
2275 | * | |
2276 | * Description: | |
2277 | * Initialize the CIPSO module and prepare it for use. Returns zero on success | |
2278 | * and negative values on failure. | |
2279 | * | |
2280 | */ | |
2281 | static int __init cipso_v4_init(void) | |
2282 | { | |
2283 | int ret_val; | |
2284 | ||
2285 | ret_val = cipso_v4_cache_init(); | |
2286 | if (ret_val != 0) | |
2287 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", | |
2288 | ret_val); | |
2289 | ||
2290 | return 0; | |
2291 | } | |
2292 | ||
2293 | subsys_initcall(cipso_v4_init); |