blob: 05b708bbdb0dedd34a04d99b16391a6b2ca4a30c [file] [log] [blame]
Paul Moore446fda42006-08-03 16:48:06 -07001/*
2 * CIPSO - Commercial IP Security Option
3 *
4 * This is an implementation of the CIPSO 2.2 protocol as specified in
5 * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in
Paul Moore586c2502009-02-20 16:32:55 -05006 * FIPS-188. While CIPSO never became a full IETF RFC standard many vendors
Paul Moore446fda42006-08-03 16:48:06 -07007 * have chosen to adopt the protocol and over the years it has become a
8 * de-facto standard for labeled networking.
9 *
Paul Moore586c2502009-02-20 16:32:55 -050010 * The CIPSO draft specification can be found in the kernel's Documentation
11 * directory as well as the following URL:
Justin P. Mattock631dd1a2010-10-18 11:03:14 +020012 * http://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt
Paul Moore586c2502009-02-20 16:32:55 -050013 * The FIPS-188 specification can be found at the following URL:
14 * http://www.itl.nist.gov/fipspubs/fip188.htm
15 *
Paul Moore446fda42006-08-03 16:48:06 -070016 * Author: Paul Moore <paul.moore@hp.com>
17 *
18 */
19
20/*
Paul Moore948bf852008-10-10 10:16:32 -040021 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008
Paul Moore446fda42006-08-03 16:48:06 -070022 *
23 * This program is free software; you can redistribute it and/or modify
24 * it under the terms of the GNU General Public License as published by
25 * the Free Software Foundation; either version 2 of the License, or
26 * (at your option) any later version.
27 *
28 * This program is distributed in the hope that it will be useful,
29 * but WITHOUT ANY WARRANTY; without even the implied warranty of
30 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
31 * the GNU General Public License for more details.
32 *
33 * You should have received a copy of the GNU General Public License
Jeff Kirshera99421d2013-12-06 09:13:39 -080034 * along with this program; if not, see <http://www.gnu.org/licenses/>.
Paul Moore446fda42006-08-03 16:48:06 -070035 *
36 */
37
38#include <linux/init.h>
39#include <linux/types.h>
40#include <linux/rcupdate.h>
41#include <linux/list.h>
42#include <linux/spinlock.h>
43#include <linux/string.h>
44#include <linux/jhash.h>
Paul Moore6c2e8ac2008-12-31 12:54:11 -050045#include <linux/audit.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090046#include <linux/slab.h>
Paul Moore446fda42006-08-03 16:48:06 -070047#include <net/ip.h>
48#include <net/icmp.h>
49#include <net/tcp.h>
50#include <net/netlabel.h>
51#include <net/cipso_ipv4.h>
Arun Sharma600634972011-07-26 16:09:06 -070052#include <linux/atomic.h>
Paul Moore446fda42006-08-03 16:48:06 -070053#include <asm/bug.h>
Paul Moore50e5d352007-06-07 18:38:14 -070054#include <asm/unaligned.h>
Paul Moore446fda42006-08-03 16:48:06 -070055
Paul Moore446fda42006-08-03 16:48:06 -070056/* List of available DOI definitions */
Paul Moore446fda42006-08-03 16:48:06 -070057/* XXX - This currently assumes a minimal number of different DOIs in use,
58 * if in practice there are a lot of different DOIs this list should
59 * probably be turned into a hash table or something similar so we
60 * can do quick lookups. */
Adrian Bunk8ce11e62006-08-07 21:50:48 -070061static DEFINE_SPINLOCK(cipso_v4_doi_list_lock);
Denis Cheng1596c972007-12-07 00:49:47 -080062static LIST_HEAD(cipso_v4_doi_list);
Paul Moore446fda42006-08-03 16:48:06 -070063
64/* Label mapping cache */
65int cipso_v4_cache_enabled = 1;
66int cipso_v4_cache_bucketsize = 10;
67#define CIPSO_V4_CACHE_BUCKETBITS 7
68#define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS)
69#define CIPSO_V4_CACHE_REORDERLIMIT 10
70struct cipso_v4_map_cache_bkt {
71 spinlock_t lock;
72 u32 size;
73 struct list_head list;
74};
75struct cipso_v4_map_cache_entry {
76 u32 hash;
77 unsigned char *key;
78 size_t key_len;
79
paul.moore@hp.comffb733c2006-10-04 11:46:31 -040080 struct netlbl_lsm_cache *lsm_data;
Paul Moore446fda42006-08-03 16:48:06 -070081
82 u32 activity;
83 struct list_head list;
84};
85static struct cipso_v4_map_cache_bkt *cipso_v4_cache = NULL;
86
87/* Restricted bitmap (tag #1) flags */
88int cipso_v4_rbm_optfmt = 0;
89int cipso_v4_rbm_strictvalid = 1;
90
91/*
Paul Mooref998e8c2007-02-28 15:14:20 -050092 * Protocol Constants
93 */
94
95/* Maximum size of the CIPSO IP option, derived from the fact that the maximum
96 * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */
97#define CIPSO_V4_OPT_LEN_MAX 40
98
99/* Length of the base CIPSO option, this includes the option type (1 byte), the
100 * option length (1 byte), and the DOI (4 bytes). */
101#define CIPSO_V4_HDR_LEN 6
102
103/* Base length of the restrictive category bitmap tag (tag #1). */
104#define CIPSO_V4_TAG_RBM_BLEN 4
105
106/* Base length of the enumerated category tag (tag #2). */
107#define CIPSO_V4_TAG_ENUM_BLEN 4
108
109/* Base length of the ranged categories bitmap tag (tag #5). */
110#define CIPSO_V4_TAG_RNG_BLEN 4
111/* The maximum number of category ranges permitted in the ranged category tag
112 * (tag #5). You may note that the IETF draft states that the maximum number
113 * of category ranges is 7, but if the low end of the last category range is
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300114 * zero then it is possible to fit 8 category ranges because the zero should
Paul Mooref998e8c2007-02-28 15:14:20 -0500115 * be omitted. */
116#define CIPSO_V4_TAG_RNG_CAT_MAX 8
117
Paul Moore15c45f72008-10-10 10:16:34 -0400118/* Base length of the local tag (non-standard tag).
119 * Tag definition (may change between kernel versions)
120 *
121 * 0 8 16 24 32
122 * +----------+----------+----------+----------+
123 * | 10000000 | 00000110 | 32-bit secid value |
124 * +----------+----------+----------+----------+
125 * | in (host byte order)|
126 * +----------+----------+
127 *
128 */
129#define CIPSO_V4_TAG_LOC_BLEN 6
130
Paul Mooref998e8c2007-02-28 15:14:20 -0500131/*
Paul Moore446fda42006-08-03 16:48:06 -0700132 * Helper Functions
133 */
134
135/**
136 * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit
137 * @bitmap: the bitmap
138 * @bitmap_len: length in bits
139 * @offset: starting offset
140 * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit
141 *
142 * Description:
143 * Starting at @offset, walk the bitmap from left to right until either the
144 * desired bit is found or we reach the end. Return the bit offset, -1 if
145 * not found, or -2 if error.
146 */
147static int cipso_v4_bitmap_walk(const unsigned char *bitmap,
148 u32 bitmap_len,
149 u32 offset,
150 u8 state)
151{
152 u32 bit_spot;
153 u32 byte_offset;
154 unsigned char bitmask;
155 unsigned char byte;
156
157 /* gcc always rounds to zero when doing integer division */
158 byte_offset = offset / 8;
159 byte = bitmap[byte_offset];
160 bit_spot = offset;
161 bitmask = 0x80 >> (offset % 8);
162
163 while (bit_spot < bitmap_len) {
164 if ((state && (byte & bitmask) == bitmask) ||
165 (state == 0 && (byte & bitmask) == 0))
166 return bit_spot;
167
168 bit_spot++;
169 bitmask >>= 1;
170 if (bitmask == 0) {
171 byte = bitmap[++byte_offset];
172 bitmask = 0x80;
173 }
174 }
175
176 return -1;
177}
178
179/**
180 * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap
181 * @bitmap: the bitmap
182 * @bit: the bit
183 * @state: if non-zero, set the bit (1) else clear the bit (0)
184 *
185 * Description:
186 * Set a single bit in the bitmask. Returns zero on success, negative values
187 * on error.
188 */
189static void cipso_v4_bitmap_setbit(unsigned char *bitmap,
190 u32 bit,
191 u8 state)
192{
193 u32 byte_spot;
194 u8 bitmask;
195
196 /* gcc always rounds to zero when doing integer division */
197 byte_spot = bit / 8;
198 bitmask = 0x80 >> (bit % 8);
199 if (state)
200 bitmap[byte_spot] |= bitmask;
201 else
202 bitmap[byte_spot] &= ~bitmask;
203}
204
205/**
Paul Moore446fda42006-08-03 16:48:06 -0700206 * cipso_v4_cache_entry_free - Frees a cache entry
207 * @entry: the entry to free
208 *
209 * Description:
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400210 * This function frees the memory associated with a cache entry including the
211 * LSM cache data if there are no longer any users, i.e. reference count == 0.
Paul Moore446fda42006-08-03 16:48:06 -0700212 *
213 */
214static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry)
215{
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400216 if (entry->lsm_data)
217 netlbl_secattr_cache_free(entry->lsm_data);
Paul Moore446fda42006-08-03 16:48:06 -0700218 kfree(entry->key);
219 kfree(entry);
220}
221
222/**
223 * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache
224 * @key: the hash key
225 * @key_len: the length of the key in bytes
226 *
227 * Description:
228 * The CIPSO tag hashing function. Returns a 32-bit hash value.
229 *
230 */
231static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len)
232{
233 return jhash(key, key_len, 0);
234}
235
236/*
237 * Label Mapping Cache Functions
238 */
239
240/**
241 * cipso_v4_cache_init - Initialize the CIPSO cache
242 *
243 * Description:
244 * Initializes the CIPSO label mapping cache, this function should be called
245 * before any of the other functions defined in this file. Returns zero on
246 * success, negative values on error.
247 *
248 */
249static int cipso_v4_cache_init(void)
250{
251 u32 iter;
252
253 cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS,
254 sizeof(struct cipso_v4_map_cache_bkt),
255 GFP_KERNEL);
256 if (cipso_v4_cache == NULL)
257 return -ENOMEM;
258
259 for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) {
260 spin_lock_init(&cipso_v4_cache[iter].lock);
261 cipso_v4_cache[iter].size = 0;
262 INIT_LIST_HEAD(&cipso_v4_cache[iter].list);
263 }
264
265 return 0;
266}
267
268/**
269 * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache
270 *
271 * Description:
272 * Invalidates and frees any entries in the CIPSO cache. Returns zero on
273 * success and negative values on failure.
274 *
275 */
276void cipso_v4_cache_invalidate(void)
277{
278 struct cipso_v4_map_cache_entry *entry, *tmp_entry;
279 u32 iter;
280
281 for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) {
Paul Moore609c92f2006-09-25 15:52:37 -0700282 spin_lock_bh(&cipso_v4_cache[iter].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700283 list_for_each_entry_safe(entry,
284 tmp_entry,
285 &cipso_v4_cache[iter].list, list) {
286 list_del(&entry->list);
287 cipso_v4_cache_entry_free(entry);
288 }
289 cipso_v4_cache[iter].size = 0;
Paul Moore609c92f2006-09-25 15:52:37 -0700290 spin_unlock_bh(&cipso_v4_cache[iter].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700291 }
Paul Moore446fda42006-08-03 16:48:06 -0700292}
293
294/**
295 * cipso_v4_cache_check - Check the CIPSO cache for a label mapping
296 * @key: the buffer to check
297 * @key_len: buffer length in bytes
298 * @secattr: the security attribute struct to use
299 *
300 * Description:
301 * This function checks the cache to see if a label mapping already exists for
302 * the given key. If there is a match then the cache is adjusted and the
303 * @secattr struct is populated with the correct LSM security attributes. The
304 * cache is adjusted in the following manner if the entry is not already the
305 * first in the cache bucket:
306 *
307 * 1. The cache entry's activity counter is incremented
308 * 2. The previous (higher ranking) entry's activity counter is decremented
309 * 3. If the difference between the two activity counters is geater than
310 * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped
311 *
312 * Returns zero on success, -ENOENT for a cache miss, and other negative values
313 * on error.
314 *
315 */
316static int cipso_v4_cache_check(const unsigned char *key,
317 u32 key_len,
318 struct netlbl_lsm_secattr *secattr)
319{
320 u32 bkt;
321 struct cipso_v4_map_cache_entry *entry;
322 struct cipso_v4_map_cache_entry *prev_entry = NULL;
323 u32 hash;
324
325 if (!cipso_v4_cache_enabled)
326 return -ENOENT;
327
328 hash = cipso_v4_map_cache_hash(key, key_len);
Pavel Emelyanov5e0f8922008-05-13 23:23:55 -0700329 bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1);
Paul Moore609c92f2006-09-25 15:52:37 -0700330 spin_lock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700331 list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) {
332 if (entry->hash == hash &&
333 entry->key_len == key_len &&
334 memcmp(entry->key, key, key_len) == 0) {
335 entry->activity += 1;
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400336 atomic_inc(&entry->lsm_data->refcount);
337 secattr->cache = entry->lsm_data;
Paul Moore701a90b2006-11-17 17:38:46 -0500338 secattr->flags |= NETLBL_SECATTR_CACHE;
Paul Moore16efd452008-01-29 08:37:59 -0500339 secattr->type = NETLBL_NLTYPE_CIPSOV4;
Paul Moore446fda42006-08-03 16:48:06 -0700340 if (prev_entry == NULL) {
Paul Moore609c92f2006-09-25 15:52:37 -0700341 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700342 return 0;
343 }
344
345 if (prev_entry->activity > 0)
346 prev_entry->activity -= 1;
347 if (entry->activity > prev_entry->activity &&
348 entry->activity - prev_entry->activity >
349 CIPSO_V4_CACHE_REORDERLIMIT) {
350 __list_del(entry->list.prev, entry->list.next);
351 __list_add(&entry->list,
352 prev_entry->list.prev,
353 &prev_entry->list);
354 }
355
Paul Moore609c92f2006-09-25 15:52:37 -0700356 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700357 return 0;
358 }
359 prev_entry = entry;
360 }
Paul Moore609c92f2006-09-25 15:52:37 -0700361 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700362
363 return -ENOENT;
364}
365
366/**
367 * cipso_v4_cache_add - Add an entry to the CIPSO cache
368 * @skb: the packet
369 * @secattr: the packet's security attributes
370 *
371 * Description:
372 * Add a new entry into the CIPSO label mapping cache. Add the new entry to
373 * head of the cache bucket's list, if the cache bucket is out of room remove
374 * the last entry in the list first. It is important to note that there is
375 * currently no checking for duplicate keys. Returns zero on success,
376 * negative values on failure.
377 *
378 */
379int cipso_v4_cache_add(const struct sk_buff *skb,
380 const struct netlbl_lsm_secattr *secattr)
381{
382 int ret_val = -EPERM;
383 u32 bkt;
384 struct cipso_v4_map_cache_entry *entry = NULL;
385 struct cipso_v4_map_cache_entry *old_entry = NULL;
386 unsigned char *cipso_ptr;
387 u32 cipso_ptr_len;
388
389 if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0)
390 return 0;
391
392 cipso_ptr = CIPSO_V4_OPTPTR(skb);
393 cipso_ptr_len = cipso_ptr[1];
394
395 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
396 if (entry == NULL)
397 return -ENOMEM;
Arnaldo Carvalho de Melofac5d732006-11-17 11:14:16 -0200398 entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC);
Paul Moore446fda42006-08-03 16:48:06 -0700399 if (entry->key == NULL) {
400 ret_val = -ENOMEM;
401 goto cache_add_failure;
402 }
Paul Moore446fda42006-08-03 16:48:06 -0700403 entry->key_len = cipso_ptr_len;
404 entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len);
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400405 atomic_inc(&secattr->cache->refcount);
406 entry->lsm_data = secattr->cache;
Paul Moore446fda42006-08-03 16:48:06 -0700407
Pavel Emelyanov5e0f8922008-05-13 23:23:55 -0700408 bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1);
Paul Moore609c92f2006-09-25 15:52:37 -0700409 spin_lock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700410 if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
411 list_add(&entry->list, &cipso_v4_cache[bkt].list);
412 cipso_v4_cache[bkt].size += 1;
413 } else {
414 old_entry = list_entry(cipso_v4_cache[bkt].list.prev,
415 struct cipso_v4_map_cache_entry, list);
416 list_del(&old_entry->list);
417 list_add(&entry->list, &cipso_v4_cache[bkt].list);
418 cipso_v4_cache_entry_free(old_entry);
419 }
Paul Moore609c92f2006-09-25 15:52:37 -0700420 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700421
422 return 0;
423
424cache_add_failure:
425 if (entry)
426 cipso_v4_cache_entry_free(entry);
427 return ret_val;
428}
429
430/*
431 * DOI List Functions
432 */
433
434/**
435 * cipso_v4_doi_search - Searches for a DOI definition
436 * @doi: the DOI to search for
437 *
438 * Description:
439 * Search the DOI definition list for a DOI definition with a DOI value that
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300440 * matches @doi. The caller is responsible for calling rcu_read_[un]lock().
Paul Moore446fda42006-08-03 16:48:06 -0700441 * Returns a pointer to the DOI definition on success and NULL on failure.
442 */
443static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
444{
445 struct cipso_v4_doi *iter;
446
447 list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
Paul Mooreb1edeb12008-10-10 10:16:31 -0400448 if (iter->doi == doi && atomic_read(&iter->refcount))
Paul Moore446fda42006-08-03 16:48:06 -0700449 return iter;
450 return NULL;
451}
452
453/**
454 * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine
455 * @doi_def: the DOI structure
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500456 * @audit_info: NetLabel audit information
Paul Moore446fda42006-08-03 16:48:06 -0700457 *
458 * Description:
459 * The caller defines a new DOI for use by the CIPSO engine and calls this
460 * function to add it to the list of acceptable domains. The caller must
461 * ensure that the mapping table specified in @doi_def->map meets all of the
462 * requirements of the mapping type (see cipso_ipv4.h for details). Returns
463 * zero on success and non-zero on failure.
464 *
465 */
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500466int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
467 struct netlbl_audit *audit_info)
Paul Moore446fda42006-08-03 16:48:06 -0700468{
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500469 int ret_val = -EINVAL;
Paul Moore6ce61a72006-11-17 17:38:48 -0500470 u32 iter;
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500471 u32 doi;
472 u32 doi_type;
473 struct audit_buffer *audit_buf;
474
475 doi = doi_def->doi;
476 doi_type = doi_def->type;
Paul Moore6ce61a72006-11-17 17:38:48 -0500477
Dan Carpenter56755922011-10-11 18:43:53 -0400478 if (doi_def->doi == CIPSO_V4_DOI_UNKNOWN)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500479 goto doi_add_return;
Paul Moore6ce61a72006-11-17 17:38:48 -0500480 for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) {
481 switch (doi_def->tags[iter]) {
482 case CIPSO_V4_TAG_RBITMAP:
483 break;
Paul Moore484b3662006-11-29 13:18:20 -0500484 case CIPSO_V4_TAG_RANGE:
Paul Moore654bbc22006-11-29 13:18:19 -0500485 case CIPSO_V4_TAG_ENUM:
486 if (doi_def->type != CIPSO_V4_MAP_PASS)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500487 goto doi_add_return;
Paul Moore654bbc22006-11-29 13:18:19 -0500488 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400489 case CIPSO_V4_TAG_LOCAL:
490 if (doi_def->type != CIPSO_V4_MAP_LOCAL)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500491 goto doi_add_return;
492 break;
493 case CIPSO_V4_TAG_INVALID:
494 if (iter == 0)
495 goto doi_add_return;
Paul Moore15c45f72008-10-10 10:16:34 -0400496 break;
Paul Moore6ce61a72006-11-17 17:38:48 -0500497 default:
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500498 goto doi_add_return;
Paul Moore6ce61a72006-11-17 17:38:48 -0500499 }
500 }
Paul Moore446fda42006-08-03 16:48:06 -0700501
Paul Mooreb1edeb12008-10-10 10:16:31 -0400502 atomic_set(&doi_def->refcount, 1);
Paul Moore446fda42006-08-03 16:48:06 -0700503
Paul Moore446fda42006-08-03 16:48:06 -0700504 spin_lock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500505 if (cipso_v4_doi_search(doi_def->doi) != NULL) {
506 spin_unlock(&cipso_v4_doi_list_lock);
507 ret_val = -EEXIST;
508 goto doi_add_return;
509 }
Paul Moore446fda42006-08-03 16:48:06 -0700510 list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list);
511 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500512 ret_val = 0;
Paul Moore446fda42006-08-03 16:48:06 -0700513
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500514doi_add_return:
515 audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info);
516 if (audit_buf != NULL) {
517 const char *type_str;
518 switch (doi_type) {
519 case CIPSO_V4_MAP_TRANS:
520 type_str = "trans";
521 break;
522 case CIPSO_V4_MAP_PASS:
523 type_str = "pass";
524 break;
525 case CIPSO_V4_MAP_LOCAL:
526 type_str = "local";
527 break;
528 default:
529 type_str = "(unknown)";
530 }
531 audit_log_format(audit_buf,
532 " cipso_doi=%u cipso_type=%s res=%u",
533 doi, type_str, ret_val == 0 ? 1 : 0);
534 audit_log_end(audit_buf);
535 }
Paul Moore446fda42006-08-03 16:48:06 -0700536
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500537 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700538}
539
540/**
Paul Mooreb1edeb12008-10-10 10:16:31 -0400541 * cipso_v4_doi_free - Frees a DOI definition
542 * @entry: the entry's RCU field
Paul Moore446fda42006-08-03 16:48:06 -0700543 *
544 * Description:
Paul Mooreb1edeb12008-10-10 10:16:31 -0400545 * This function frees all of the memory associated with a DOI definition.
Paul Moore446fda42006-08-03 16:48:06 -0700546 *
547 */
Paul Mooreb1edeb12008-10-10 10:16:31 -0400548void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
Paul Moore446fda42006-08-03 16:48:06 -0700549{
Paul Mooreb1edeb12008-10-10 10:16:31 -0400550 if (doi_def == NULL)
551 return;
Paul Moore446fda42006-08-03 16:48:06 -0700552
Paul Mooreb1edeb12008-10-10 10:16:31 -0400553 switch (doi_def->type) {
Paul Moore15c45f72008-10-10 10:16:34 -0400554 case CIPSO_V4_MAP_TRANS:
Paul Mooreb1edeb12008-10-10 10:16:31 -0400555 kfree(doi_def->map.std->lvl.cipso);
556 kfree(doi_def->map.std->lvl.local);
557 kfree(doi_def->map.std->cat.cipso);
558 kfree(doi_def->map.std->cat.local);
559 break;
Paul Moore446fda42006-08-03 16:48:06 -0700560 }
Paul Mooreb1edeb12008-10-10 10:16:31 -0400561 kfree(doi_def);
Paul Moore446fda42006-08-03 16:48:06 -0700562}
563
564/**
Paul Mooreb1edeb12008-10-10 10:16:31 -0400565 * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer
566 * @entry: the entry's RCU field
567 *
568 * Description:
569 * This function is designed to be used as a callback to the call_rcu()
570 * function so that the memory allocated to the DOI definition can be released
571 * safely.
572 *
573 */
574static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
575{
576 struct cipso_v4_doi *doi_def;
577
578 doi_def = container_of(entry, struct cipso_v4_doi, rcu);
579 cipso_v4_doi_free(doi_def);
580}
581
582/**
583 * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
584 * @doi: the DOI value
585 * @audit_secid: the LSM secid to use in the audit message
586 *
587 * Description:
588 * Removes a DOI definition from the CIPSO engine. The NetLabel routines will
589 * be called to release their own LSM domain mappings as well as our own
590 * domain list. Returns zero on success and negative values on failure.
591 *
592 */
593int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
594{
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500595 int ret_val;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400596 struct cipso_v4_doi *doi_def;
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500597 struct audit_buffer *audit_buf;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400598
599 spin_lock(&cipso_v4_doi_list_lock);
600 doi_def = cipso_v4_doi_search(doi);
601 if (doi_def == NULL) {
602 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500603 ret_val = -ENOENT;
604 goto doi_remove_return;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400605 }
606 if (!atomic_dec_and_test(&doi_def->refcount)) {
607 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500608 ret_val = -EBUSY;
609 goto doi_remove_return;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400610 }
611 list_del_rcu(&doi_def->list);
612 spin_unlock(&cipso_v4_doi_list_lock);
613
614 cipso_v4_cache_invalidate();
615 call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500616 ret_val = 0;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400617
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500618doi_remove_return:
619 audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info);
620 if (audit_buf != NULL) {
621 audit_log_format(audit_buf,
622 " cipso_doi=%u res=%u",
623 doi, ret_val == 0 ? 1 : 0);
624 audit_log_end(audit_buf);
625 }
626
627 return ret_val;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400628}
629
630/**
631 * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition
Paul Moore446fda42006-08-03 16:48:06 -0700632 * @doi: the DOI value
633 *
634 * Description:
635 * Searches for a valid DOI definition and if one is found it is returned to
636 * the caller. Otherwise NULL is returned. The caller must ensure that
Paul Mooreb1edeb12008-10-10 10:16:31 -0400637 * rcu_read_lock() is held while accessing the returned definition and the DOI
638 * definition reference count is decremented when the caller is done.
Paul Moore446fda42006-08-03 16:48:06 -0700639 *
640 */
641struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
642{
Paul Mooreb1edeb12008-10-10 10:16:31 -0400643 struct cipso_v4_doi *doi_def;
644
645 rcu_read_lock();
646 doi_def = cipso_v4_doi_search(doi);
647 if (doi_def == NULL)
648 goto doi_getdef_return;
649 if (!atomic_inc_not_zero(&doi_def->refcount))
650 doi_def = NULL;
651
652doi_getdef_return:
653 rcu_read_unlock();
654 return doi_def;
655}
656
657/**
658 * cipso_v4_doi_putdef - Releases a reference for the given DOI definition
659 * @doi_def: the DOI definition
660 *
661 * Description:
662 * Releases a DOI definition reference obtained from cipso_v4_doi_getdef().
663 *
664 */
665void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
666{
667 if (doi_def == NULL)
668 return;
669
670 if (!atomic_dec_and_test(&doi_def->refcount))
671 return;
672 spin_lock(&cipso_v4_doi_list_lock);
673 list_del_rcu(&doi_def->list);
674 spin_unlock(&cipso_v4_doi_list_lock);
675
676 cipso_v4_cache_invalidate();
677 call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
Paul Moore446fda42006-08-03 16:48:06 -0700678}
679
680/**
Paul Moorefcd48282006-09-25 15:56:09 -0700681 * cipso_v4_doi_walk - Iterate through the DOI definitions
682 * @skip_cnt: skip past this number of DOI definitions, updated
683 * @callback: callback for each DOI definition
684 * @cb_arg: argument for the callback function
Paul Moore446fda42006-08-03 16:48:06 -0700685 *
686 * Description:
Paul Moorefcd48282006-09-25 15:56:09 -0700687 * Iterate over the DOI definition list, skipping the first @skip_cnt entries.
688 * For each entry call @callback, if @callback returns a negative value stop
689 * 'walking' through the list and return. Updates the value in @skip_cnt upon
690 * return. Returns zero on success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -0700691 *
692 */
Paul Moorefcd48282006-09-25 15:56:09 -0700693int cipso_v4_doi_walk(u32 *skip_cnt,
694 int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
695 void *cb_arg)
Paul Moore446fda42006-08-03 16:48:06 -0700696{
Paul Moorefcd48282006-09-25 15:56:09 -0700697 int ret_val = -ENOENT;
Paul Moore446fda42006-08-03 16:48:06 -0700698 u32 doi_cnt = 0;
Paul Moorefcd48282006-09-25 15:56:09 -0700699 struct cipso_v4_doi *iter_doi;
Paul Moore446fda42006-08-03 16:48:06 -0700700
701 rcu_read_lock();
Paul Moorefcd48282006-09-25 15:56:09 -0700702 list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
Paul Mooreb1edeb12008-10-10 10:16:31 -0400703 if (atomic_read(&iter_doi->refcount) > 0) {
Paul Moorefcd48282006-09-25 15:56:09 -0700704 if (doi_cnt++ < *skip_cnt)
705 continue;
706 ret_val = callback(iter_doi, cb_arg);
707 if (ret_val < 0) {
708 doi_cnt--;
709 goto doi_walk_return;
Paul Moore446fda42006-08-03 16:48:06 -0700710 }
Paul Moorefcd48282006-09-25 15:56:09 -0700711 }
Paul Moore446fda42006-08-03 16:48:06 -0700712
Paul Moorefcd48282006-09-25 15:56:09 -0700713doi_walk_return:
Paul Moore446fda42006-08-03 16:48:06 -0700714 rcu_read_unlock();
Paul Moorefcd48282006-09-25 15:56:09 -0700715 *skip_cnt = doi_cnt;
716 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700717}
718
Paul Moore446fda42006-08-03 16:48:06 -0700719/*
720 * Label Mapping Functions
721 */
722
723/**
724 * cipso_v4_map_lvl_valid - Checks to see if the given level is understood
725 * @doi_def: the DOI definition
726 * @level: the level to check
727 *
728 * Description:
729 * Checks the given level against the given DOI definition and returns a
730 * negative value if the level does not have a valid mapping and a zero value
731 * if the level is defined by the DOI.
732 *
733 */
734static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level)
735{
736 switch (doi_def->type) {
737 case CIPSO_V4_MAP_PASS:
738 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400739 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700740 if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)
741 return 0;
742 break;
743 }
744
745 return -EFAULT;
746}
747
748/**
749 * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network
750 * @doi_def: the DOI definition
751 * @host_lvl: the host MLS level
752 * @net_lvl: the network/CIPSO MLS level
753 *
754 * Description:
755 * Perform a label mapping to translate a local MLS level to the correct
756 * CIPSO level using the given DOI definition. Returns zero on success,
757 * negative values otherwise.
758 *
759 */
760static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def,
761 u32 host_lvl,
762 u32 *net_lvl)
763{
764 switch (doi_def->type) {
765 case CIPSO_V4_MAP_PASS:
766 *net_lvl = host_lvl;
767 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400768 case CIPSO_V4_MAP_TRANS:
Paul Moorec6387a82007-03-02 13:19:02 -0800769 if (host_lvl < doi_def->map.std->lvl.local_size &&
770 doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) {
Paul Moore446fda42006-08-03 16:48:06 -0700771 *net_lvl = doi_def->map.std->lvl.local[host_lvl];
772 return 0;
773 }
Paul Moorec6387a82007-03-02 13:19:02 -0800774 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700775 }
776
777 return -EINVAL;
778}
779
780/**
781 * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host
782 * @doi_def: the DOI definition
783 * @net_lvl: the network/CIPSO MLS level
784 * @host_lvl: the host MLS level
785 *
786 * Description:
787 * Perform a label mapping to translate a CIPSO level to the correct local MLS
788 * level using the given DOI definition. Returns zero on success, negative
789 * values otherwise.
790 *
791 */
792static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def,
793 u32 net_lvl,
794 u32 *host_lvl)
795{
796 struct cipso_v4_std_map_tbl *map_tbl;
797
798 switch (doi_def->type) {
799 case CIPSO_V4_MAP_PASS:
800 *host_lvl = net_lvl;
801 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400802 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700803 map_tbl = doi_def->map.std;
804 if (net_lvl < map_tbl->lvl.cipso_size &&
805 map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) {
806 *host_lvl = doi_def->map.std->lvl.cipso[net_lvl];
807 return 0;
808 }
Paul Moorec6387a82007-03-02 13:19:02 -0800809 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700810 }
811
812 return -EINVAL;
813}
814
815/**
816 * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid
817 * @doi_def: the DOI definition
818 * @bitmap: category bitmap
819 * @bitmap_len: bitmap length in bytes
820 *
821 * Description:
822 * Checks the given category bitmap against the given DOI definition and
823 * returns a negative value if any of the categories in the bitmap do not have
824 * a valid mapping and a zero value if all of the categories are valid.
825 *
826 */
827static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def,
828 const unsigned char *bitmap,
829 u32 bitmap_len)
830{
831 int cat = -1;
832 u32 bitmap_len_bits = bitmap_len * 8;
Paul Moore044a68e2006-10-11 19:10:47 -0400833 u32 cipso_cat_size;
834 u32 *cipso_array;
Paul Moore446fda42006-08-03 16:48:06 -0700835
836 switch (doi_def->type) {
837 case CIPSO_V4_MAP_PASS:
838 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400839 case CIPSO_V4_MAP_TRANS:
Paul Moore044a68e2006-10-11 19:10:47 -0400840 cipso_cat_size = doi_def->map.std->cat.cipso_size;
841 cipso_array = doi_def->map.std->cat.cipso;
Paul Moore446fda42006-08-03 16:48:06 -0700842 for (;;) {
843 cat = cipso_v4_bitmap_walk(bitmap,
844 bitmap_len_bits,
845 cat + 1,
846 1);
847 if (cat < 0)
848 break;
849 if (cat >= cipso_cat_size ||
850 cipso_array[cat] >= CIPSO_V4_INV_CAT)
851 return -EFAULT;
852 }
853
854 if (cat == -1)
855 return 0;
856 break;
857 }
858
859 return -EFAULT;
860}
861
862/**
863 * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network
864 * @doi_def: the DOI definition
Paul Moore02752762006-11-29 13:18:18 -0500865 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -0700866 * @net_cat: the zero'd out category bitmap in network/CIPSO format
867 * @net_cat_len: the length of the CIPSO bitmap in bytes
868 *
869 * Description:
870 * Perform a label mapping to translate a local MLS category bitmap to the
871 * correct CIPSO bitmap using the given DOI definition. Returns the minimum
872 * size in bytes of the network bitmap on success, negative values otherwise.
873 *
874 */
875static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def,
Paul Moore02752762006-11-29 13:18:18 -0500876 const struct netlbl_lsm_secattr *secattr,
Paul Moore446fda42006-08-03 16:48:06 -0700877 unsigned char *net_cat,
878 u32 net_cat_len)
879{
880 int host_spot = -1;
Paul Moore02752762006-11-29 13:18:18 -0500881 u32 net_spot = CIPSO_V4_INV_CAT;
Paul Moore446fda42006-08-03 16:48:06 -0700882 u32 net_spot_max = 0;
Paul Moore446fda42006-08-03 16:48:06 -0700883 u32 net_clen_bits = net_cat_len * 8;
Paul Moore02752762006-11-29 13:18:18 -0500884 u32 host_cat_size = 0;
885 u32 *host_cat_array = NULL;
Paul Moore446fda42006-08-03 16:48:06 -0700886
Paul Moore15c45f72008-10-10 10:16:34 -0400887 if (doi_def->type == CIPSO_V4_MAP_TRANS) {
Paul Moore044a68e2006-10-11 19:10:47 -0400888 host_cat_size = doi_def->map.std->cat.local_size;
889 host_cat_array = doi_def->map.std->cat.local;
Paul Moore02752762006-11-29 13:18:18 -0500890 }
891
892 for (;;) {
Paul Moore4fbe63d2014-08-01 11:17:37 -0400893 host_spot = netlbl_catmap_walk(secattr->attr.mls.cat,
894 host_spot + 1);
Paul Moore02752762006-11-29 13:18:18 -0500895 if (host_spot < 0)
896 break;
897
898 switch (doi_def->type) {
899 case CIPSO_V4_MAP_PASS:
900 net_spot = host_spot;
901 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400902 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700903 if (host_spot >= host_cat_size)
904 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700905 net_spot = host_cat_array[host_spot];
Paul Moore9fade4b2006-11-17 17:38:50 -0500906 if (net_spot >= CIPSO_V4_INV_CAT)
907 return -EPERM;
Paul Moore02752762006-11-29 13:18:18 -0500908 break;
Paul Moore446fda42006-08-03 16:48:06 -0700909 }
Paul Moore02752762006-11-29 13:18:18 -0500910 if (net_spot >= net_clen_bits)
911 return -ENOSPC;
912 cipso_v4_bitmap_setbit(net_cat, net_spot, 1);
Paul Moore446fda42006-08-03 16:48:06 -0700913
Paul Moore02752762006-11-29 13:18:18 -0500914 if (net_spot > net_spot_max)
915 net_spot_max = net_spot;
Paul Moore446fda42006-08-03 16:48:06 -0700916 }
917
Paul Moore02752762006-11-29 13:18:18 -0500918 if (++net_spot_max % 8)
919 return net_spot_max / 8 + 1;
920 return net_spot_max / 8;
Paul Moore446fda42006-08-03 16:48:06 -0700921}
922
923/**
924 * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host
925 * @doi_def: the DOI definition
926 * @net_cat: the category bitmap in network/CIPSO format
927 * @net_cat_len: the length of the CIPSO bitmap in bytes
Paul Moore02752762006-11-29 13:18:18 -0500928 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -0700929 *
930 * Description:
931 * Perform a label mapping to translate a CIPSO bitmap to the correct local
Paul Moore02752762006-11-29 13:18:18 -0500932 * MLS category bitmap using the given DOI definition. Returns zero on
933 * success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -0700934 *
935 */
936static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
937 const unsigned char *net_cat,
938 u32 net_cat_len,
Paul Moore02752762006-11-29 13:18:18 -0500939 struct netlbl_lsm_secattr *secattr)
Paul Moore446fda42006-08-03 16:48:06 -0700940{
Paul Moore02752762006-11-29 13:18:18 -0500941 int ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700942 int net_spot = -1;
Paul Moore02752762006-11-29 13:18:18 -0500943 u32 host_spot = CIPSO_V4_INV_CAT;
Paul Moore446fda42006-08-03 16:48:06 -0700944 u32 net_clen_bits = net_cat_len * 8;
Paul Moore02752762006-11-29 13:18:18 -0500945 u32 net_cat_size = 0;
946 u32 *net_cat_array = NULL;
Paul Moore446fda42006-08-03 16:48:06 -0700947
Paul Moore15c45f72008-10-10 10:16:34 -0400948 if (doi_def->type == CIPSO_V4_MAP_TRANS) {
Paul Moore044a68e2006-10-11 19:10:47 -0400949 net_cat_size = doi_def->map.std->cat.cipso_size;
950 net_cat_array = doi_def->map.std->cat.cipso;
Paul Moore02752762006-11-29 13:18:18 -0500951 }
Paul Moore446fda42006-08-03 16:48:06 -0700952
Paul Moore02752762006-11-29 13:18:18 -0500953 for (;;) {
954 net_spot = cipso_v4_bitmap_walk(net_cat,
955 net_clen_bits,
956 net_spot + 1,
957 1);
958 if (net_spot < 0) {
959 if (net_spot == -2)
960 return -EFAULT;
961 return 0;
962 }
963
964 switch (doi_def->type) {
965 case CIPSO_V4_MAP_PASS:
966 host_spot = net_spot;
967 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400968 case CIPSO_V4_MAP_TRANS:
Paul Moore02752762006-11-29 13:18:18 -0500969 if (net_spot >= net_cat_size)
970 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700971 host_spot = net_cat_array[net_spot];
Paul Moore9fade4b2006-11-17 17:38:50 -0500972 if (host_spot >= CIPSO_V4_INV_CAT)
973 return -EPERM;
Paul Moore02752762006-11-29 13:18:18 -0500974 break;
Paul Moore446fda42006-08-03 16:48:06 -0700975 }
Paul Moore4fbe63d2014-08-01 11:17:37 -0400976 ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat,
Paul Moore02752762006-11-29 13:18:18 -0500977 host_spot,
978 GFP_ATOMIC);
979 if (ret_val != 0)
980 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700981 }
982
983 return -EINVAL;
984}
985
Paul Moore654bbc22006-11-29 13:18:19 -0500986/**
987 * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid
988 * @doi_def: the DOI definition
989 * @enumcat: category list
990 * @enumcat_len: length of the category list in bytes
991 *
992 * Description:
993 * Checks the given categories against the given DOI definition and returns a
994 * negative value if any of the categories do not have a valid mapping and a
995 * zero value if all of the categories are valid.
996 *
997 */
998static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def,
999 const unsigned char *enumcat,
1000 u32 enumcat_len)
1001{
1002 u16 cat;
1003 int cat_prev = -1;
1004 u32 iter;
1005
1006 if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01)
1007 return -EFAULT;
1008
1009 for (iter = 0; iter < enumcat_len; iter += 2) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001010 cat = get_unaligned_be16(&enumcat[iter]);
Paul Moore654bbc22006-11-29 13:18:19 -05001011 if (cat <= cat_prev)
1012 return -EFAULT;
1013 cat_prev = cat;
1014 }
1015
1016 return 0;
1017}
1018
1019/**
1020 * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network
1021 * @doi_def: the DOI definition
1022 * @secattr: the security attributes
1023 * @net_cat: the zero'd out category list in network/CIPSO format
1024 * @net_cat_len: the length of the CIPSO category list in bytes
1025 *
1026 * Description:
1027 * Perform a label mapping to translate a local MLS category bitmap to the
1028 * correct CIPSO category list using the given DOI definition. Returns the
1029 * size in bytes of the network category bitmap on success, negative values
1030 * otherwise.
1031 *
1032 */
1033static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def,
1034 const struct netlbl_lsm_secattr *secattr,
1035 unsigned char *net_cat,
1036 u32 net_cat_len)
1037{
1038 int cat = -1;
1039 u32 cat_iter = 0;
1040
1041 for (;;) {
Paul Moore4fbe63d2014-08-01 11:17:37 -04001042 cat = netlbl_catmap_walk(secattr->attr.mls.cat, cat + 1);
Paul Moore654bbc22006-11-29 13:18:19 -05001043 if (cat < 0)
1044 break;
1045 if ((cat_iter + 2) > net_cat_len)
1046 return -ENOSPC;
1047
1048 *((__be16 *)&net_cat[cat_iter]) = htons(cat);
1049 cat_iter += 2;
1050 }
1051
1052 return cat_iter;
1053}
1054
1055/**
1056 * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host
1057 * @doi_def: the DOI definition
1058 * @net_cat: the category list in network/CIPSO format
1059 * @net_cat_len: the length of the CIPSO bitmap in bytes
1060 * @secattr: the security attributes
1061 *
1062 * Description:
1063 * Perform a label mapping to translate a CIPSO category list to the correct
1064 * local MLS category bitmap using the given DOI definition. Returns zero on
1065 * success, negative values on failure.
1066 *
1067 */
1068static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def,
1069 const unsigned char *net_cat,
1070 u32 net_cat_len,
1071 struct netlbl_lsm_secattr *secattr)
1072{
1073 int ret_val;
1074 u32 iter;
1075
1076 for (iter = 0; iter < net_cat_len; iter += 2) {
Paul Moore4fbe63d2014-08-01 11:17:37 -04001077 ret_val = netlbl_catmap_setbit(&secattr->attr.mls.cat,
1078 get_unaligned_be16(&net_cat[iter]),
1079 GFP_ATOMIC);
Paul Moore654bbc22006-11-29 13:18:19 -05001080 if (ret_val != 0)
1081 return ret_val;
1082 }
1083
1084 return 0;
1085}
1086
Paul Moore484b3662006-11-29 13:18:20 -05001087/**
1088 * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid
1089 * @doi_def: the DOI definition
1090 * @rngcat: category list
1091 * @rngcat_len: length of the category list in bytes
1092 *
1093 * Description:
1094 * Checks the given categories against the given DOI definition and returns a
1095 * negative value if any of the categories do not have a valid mapping and a
1096 * zero value if all of the categories are valid.
1097 *
1098 */
1099static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def,
1100 const unsigned char *rngcat,
1101 u32 rngcat_len)
1102{
1103 u16 cat_high;
1104 u16 cat_low;
1105 u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1;
1106 u32 iter;
1107
1108 if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01)
1109 return -EFAULT;
1110
1111 for (iter = 0; iter < rngcat_len; iter += 4) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001112 cat_high = get_unaligned_be16(&rngcat[iter]);
Paul Moore484b3662006-11-29 13:18:20 -05001113 if ((iter + 4) <= rngcat_len)
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001114 cat_low = get_unaligned_be16(&rngcat[iter + 2]);
Paul Moore484b3662006-11-29 13:18:20 -05001115 else
1116 cat_low = 0;
1117
1118 if (cat_high > cat_prev)
1119 return -EFAULT;
1120
1121 cat_prev = cat_low;
1122 }
1123
1124 return 0;
1125}
1126
1127/**
1128 * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network
1129 * @doi_def: the DOI definition
1130 * @secattr: the security attributes
1131 * @net_cat: the zero'd out category list in network/CIPSO format
1132 * @net_cat_len: the length of the CIPSO category list in bytes
1133 *
1134 * Description:
1135 * Perform a label mapping to translate a local MLS category bitmap to the
1136 * correct CIPSO category list using the given DOI definition. Returns the
1137 * size in bytes of the network category bitmap on success, negative values
1138 * otherwise.
1139 *
1140 */
1141static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def,
1142 const struct netlbl_lsm_secattr *secattr,
1143 unsigned char *net_cat,
1144 u32 net_cat_len)
1145{
Paul Moore484b3662006-11-29 13:18:20 -05001146 int iter = -1;
Paul Mooref998e8c2007-02-28 15:14:20 -05001147 u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2];
Paul Moore484b3662006-11-29 13:18:20 -05001148 u32 array_cnt = 0;
1149 u32 cat_size = 0;
1150
Paul Mooref998e8c2007-02-28 15:14:20 -05001151 /* make sure we don't overflow the 'array[]' variable */
Paul Moore128c6b62007-02-28 15:14:21 -05001152 if (net_cat_len >
1153 (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN))
1154 return -ENOSPC;
Paul Moore484b3662006-11-29 13:18:20 -05001155
1156 for (;;) {
Paul Moore4fbe63d2014-08-01 11:17:37 -04001157 iter = netlbl_catmap_walk(secattr->attr.mls.cat, iter + 1);
Paul Moore484b3662006-11-29 13:18:20 -05001158 if (iter < 0)
1159 break;
1160 cat_size += (iter == 0 ? 0 : sizeof(u16));
1161 if (cat_size > net_cat_len)
1162 return -ENOSPC;
1163 array[array_cnt++] = iter;
1164
Paul Moore4fbe63d2014-08-01 11:17:37 -04001165 iter = netlbl_catmap_walkrng(secattr->attr.mls.cat, iter);
Paul Moore484b3662006-11-29 13:18:20 -05001166 if (iter < 0)
1167 return -EFAULT;
1168 cat_size += sizeof(u16);
1169 if (cat_size > net_cat_len)
1170 return -ENOSPC;
1171 array[array_cnt++] = iter;
1172 }
1173
1174 for (iter = 0; array_cnt > 0;) {
1175 *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]);
1176 iter += 2;
1177 array_cnt--;
1178 if (array[array_cnt] != 0) {
1179 *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]);
1180 iter += 2;
1181 }
1182 }
1183
1184 return cat_size;
1185}
1186
1187/**
1188 * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host
1189 * @doi_def: the DOI definition
1190 * @net_cat: the category list in network/CIPSO format
1191 * @net_cat_len: the length of the CIPSO bitmap in bytes
1192 * @secattr: the security attributes
1193 *
1194 * Description:
1195 * Perform a label mapping to translate a CIPSO category list to the correct
1196 * local MLS category bitmap using the given DOI definition. Returns zero on
1197 * success, negative values on failure.
1198 *
1199 */
1200static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def,
1201 const unsigned char *net_cat,
1202 u32 net_cat_len,
1203 struct netlbl_lsm_secattr *secattr)
1204{
1205 int ret_val;
1206 u32 net_iter;
1207 u16 cat_low;
1208 u16 cat_high;
1209
Stephen Hemminger132adf52007-03-08 20:44:43 -08001210 for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001211 cat_high = get_unaligned_be16(&net_cat[net_iter]);
Paul Moore484b3662006-11-29 13:18:20 -05001212 if ((net_iter + 4) <= net_cat_len)
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001213 cat_low = get_unaligned_be16(&net_cat[net_iter + 2]);
Paul Moore484b3662006-11-29 13:18:20 -05001214 else
1215 cat_low = 0;
1216
Paul Moore4fbe63d2014-08-01 11:17:37 -04001217 ret_val = netlbl_catmap_setrng(&secattr->attr.mls.cat,
1218 cat_low,
1219 cat_high,
1220 GFP_ATOMIC);
Paul Moore484b3662006-11-29 13:18:20 -05001221 if (ret_val != 0)
1222 return ret_val;
1223 }
1224
1225 return 0;
1226}
1227
Paul Moore446fda42006-08-03 16:48:06 -07001228/*
1229 * Protocol Handling Functions
1230 */
1231
Paul Moore446fda42006-08-03 16:48:06 -07001232/**
1233 * cipso_v4_gentag_hdr - Generate a CIPSO option header
1234 * @doi_def: the DOI definition
Paul Moore91b1ed02006-11-17 17:38:49 -05001235 * @len: the total tag length in bytes, not including this header
Paul Moore446fda42006-08-03 16:48:06 -07001236 * @buf: the CIPSO option buffer
1237 *
1238 * Description:
Paul Moore91b1ed02006-11-17 17:38:49 -05001239 * Write a CIPSO header into the beginning of @buffer.
Paul Moore446fda42006-08-03 16:48:06 -07001240 *
1241 */
Paul Moore91b1ed02006-11-17 17:38:49 -05001242static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def,
1243 unsigned char *buf,
1244 u32 len)
Paul Moore446fda42006-08-03 16:48:06 -07001245{
Paul Moore446fda42006-08-03 16:48:06 -07001246 buf[0] = IPOPT_CIPSO;
1247 buf[1] = CIPSO_V4_HDR_LEN + len;
Al Viro714e85b2006-11-14 20:51:49 -08001248 *(__be32 *)&buf[2] = htonl(doi_def->doi);
Paul Moore446fda42006-08-03 16:48:06 -07001249}
1250
Paul Moore446fda42006-08-03 16:48:06 -07001251/**
1252 * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1)
1253 * @doi_def: the DOI definition
1254 * @secattr: the security attributes
1255 * @buffer: the option buffer
1256 * @buffer_len: length of buffer in bytes
1257 *
1258 * Description:
1259 * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The
1260 * actual buffer length may be larger than the indicated size due to
Paul Moore91b1ed02006-11-17 17:38:49 -05001261 * translation between host and network category bitmaps. Returns the size of
1262 * the tag on success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -07001263 *
1264 */
1265static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
1266 const struct netlbl_lsm_secattr *secattr,
Paul Moore91b1ed02006-11-17 17:38:49 -05001267 unsigned char *buffer,
1268 u32 buffer_len)
Paul Moore446fda42006-08-03 16:48:06 -07001269{
Paul Moore701a90b2006-11-17 17:38:46 -05001270 int ret_val;
Paul Moore91b1ed02006-11-17 17:38:49 -05001271 u32 tag_len;
Paul Moore446fda42006-08-03 16:48:06 -07001272 u32 level;
1273
Paul Moore701a90b2006-11-17 17:38:46 -05001274 if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0)
1275 return -EPERM;
1276
Paul Moore16efd452008-01-29 08:37:59 -05001277 ret_val = cipso_v4_map_lvl_hton(doi_def,
1278 secattr->attr.mls.lvl,
1279 &level);
Paul Moore91b1ed02006-11-17 17:38:49 -05001280 if (ret_val != 0)
1281 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001282
Paul Moore91b1ed02006-11-17 17:38:49 -05001283 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
Paul Moore446fda42006-08-03 16:48:06 -07001284 ret_val = cipso_v4_map_cat_rbm_hton(doi_def,
Paul Moore02752762006-11-29 13:18:18 -05001285 secattr,
Paul Moore91b1ed02006-11-17 17:38:49 -05001286 &buffer[4],
1287 buffer_len - 4);
Paul Moore446fda42006-08-03 16:48:06 -07001288 if (ret_val < 0)
Paul Moore91b1ed02006-11-17 17:38:49 -05001289 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001290
1291 /* This will send packets using the "optimized" format when
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001292 * possible as specified in section 3.4.2.6 of the
Paul Moore446fda42006-08-03 16:48:06 -07001293 * CIPSO draft. */
Paul Moore701a90b2006-11-17 17:38:46 -05001294 if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
Paul Moore91b1ed02006-11-17 17:38:49 -05001295 tag_len = 14;
Paul Moore701a90b2006-11-17 17:38:46 -05001296 else
Paul Moore91b1ed02006-11-17 17:38:49 -05001297 tag_len = 4 + ret_val;
1298 } else
1299 tag_len = 4;
Paul Moore446fda42006-08-03 16:48:06 -07001300
Paul Moore15c45f72008-10-10 10:16:34 -04001301 buffer[0] = CIPSO_V4_TAG_RBITMAP;
Paul Moore91b1ed02006-11-17 17:38:49 -05001302 buffer[1] = tag_len;
1303 buffer[3] = level;
Paul Moore446fda42006-08-03 16:48:06 -07001304
Paul Moore91b1ed02006-11-17 17:38:49 -05001305 return tag_len;
Paul Moore446fda42006-08-03 16:48:06 -07001306}
1307
1308/**
1309 * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag
1310 * @doi_def: the DOI definition
1311 * @tag: the CIPSO tag
1312 * @secattr: the security attributes
1313 *
1314 * Description:
1315 * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security
1316 * attributes in @secattr. Return zero on success, negatives values on
1317 * failure.
1318 *
1319 */
1320static int cipso_v4_parsetag_rbm(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;
Paul Moore16efd452008-01-29 08:37:59 -05001331 secattr->attr.mls.lvl = level;
Paul Moore701a90b2006-11-17 17:38:46 -05001332 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
Paul Moore446fda42006-08-03 16:48:06 -07001333
1334 if (tag_len > 4) {
Paul Moore446fda42006-08-03 16:48:06 -07001335 ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def,
1336 &tag[4],
1337 tag_len - 4,
Paul Moore02752762006-11-29 13:18:18 -05001338 secattr);
1339 if (ret_val != 0) {
Paul Moore4fbe63d2014-08-01 11:17:37 -04001340 netlbl_catmap_free(secattr->attr.mls.cat);
Paul Moore446fda42006-08-03 16:48:06 -07001341 return ret_val;
1342 }
Paul Moore02752762006-11-29 13:18:18 -05001343
1344 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
Paul Moore446fda42006-08-03 16:48:06 -07001345 }
1346
1347 return 0;
1348}
1349
1350/**
Paul Moore654bbc22006-11-29 13:18:19 -05001351 * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2)
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 enumerated tag, tag type #2. Returns the
1359 * size of the tag on success, negative values on failure.
1360 *
1361 */
1362static int cipso_v4_gentag_enum(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
Paul Moore16efd452008-01-29 08:37:59 -05001374 ret_val = cipso_v4_map_lvl_hton(doi_def,
1375 secattr->attr.mls.lvl,
1376 &level);
Paul Moore654bbc22006-11-29 13:18:19 -05001377 if (ret_val != 0)
1378 return ret_val;
1379
1380 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
1381 ret_val = cipso_v4_map_cat_enum_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
Paul Moore15c45f72008-10-10 10:16:34 -04001392 buffer[0] = CIPSO_V4_TAG_ENUM;
Paul Moore654bbc22006-11-29 13:18:19 -05001393 buffer[1] = tag_len;
1394 buffer[3] = level;
1395
1396 return tag_len;
1397}
1398
1399/**
1400 * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag
1401 * @doi_def: the DOI definition
1402 * @tag: the CIPSO tag
1403 * @secattr: the security attributes
1404 *
1405 * Description:
1406 * Parse a CIPSO enumerated tag (tag type #2) and return the security
1407 * attributes in @secattr. Return zero on success, negatives values on
1408 * failure.
1409 *
1410 */
1411static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def,
1412 const unsigned char *tag,
1413 struct netlbl_lsm_secattr *secattr)
1414{
1415 int ret_val;
1416 u8 tag_len = tag[1];
1417 u32 level;
1418
1419 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1420 if (ret_val != 0)
1421 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001422 secattr->attr.mls.lvl = level;
Paul Moore654bbc22006-11-29 13:18:19 -05001423 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
1424
1425 if (tag_len > 4) {
Paul Moore654bbc22006-11-29 13:18:19 -05001426 ret_val = cipso_v4_map_cat_enum_ntoh(doi_def,
1427 &tag[4],
1428 tag_len - 4,
1429 secattr);
1430 if (ret_val != 0) {
Paul Moore4fbe63d2014-08-01 11:17:37 -04001431 netlbl_catmap_free(secattr->attr.mls.cat);
Paul Moore654bbc22006-11-29 13:18:19 -05001432 return ret_val;
1433 }
1434
1435 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
1436 }
1437
1438 return 0;
1439}
1440
1441/**
Paul Moore484b3662006-11-29 13:18:20 -05001442 * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5)
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 ranged tag, tag type #5. Returns the
1450 * size of the tag on success, negative values on failure.
1451 *
1452 */
1453static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def,
1454 const struct netlbl_lsm_secattr *secattr,
1455 unsigned char *buffer,
1456 u32 buffer_len)
1457{
1458 int ret_val;
1459 u32 tag_len;
1460 u32 level;
1461
1462 if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL))
1463 return -EPERM;
1464
Paul Moore16efd452008-01-29 08:37:59 -05001465 ret_val = cipso_v4_map_lvl_hton(doi_def,
1466 secattr->attr.mls.lvl,
1467 &level);
Paul Moore484b3662006-11-29 13:18:20 -05001468 if (ret_val != 0)
1469 return ret_val;
1470
1471 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
1472 ret_val = cipso_v4_map_cat_rng_hton(doi_def,
1473 secattr,
1474 &buffer[4],
1475 buffer_len - 4);
1476 if (ret_val < 0)
1477 return ret_val;
1478
1479 tag_len = 4 + ret_val;
1480 } else
1481 tag_len = 4;
1482
Paul Moore15c45f72008-10-10 10:16:34 -04001483 buffer[0] = CIPSO_V4_TAG_RANGE;
Paul Moore484b3662006-11-29 13:18:20 -05001484 buffer[1] = tag_len;
1485 buffer[3] = level;
1486
1487 return tag_len;
1488}
1489
1490/**
1491 * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag
1492 * @doi_def: the DOI definition
1493 * @tag: the CIPSO tag
1494 * @secattr: the security attributes
1495 *
1496 * Description:
1497 * Parse a CIPSO ranged tag (tag type #5) and return the security attributes
1498 * in @secattr. Return zero on success, negatives values on failure.
1499 *
1500 */
1501static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def,
1502 const unsigned char *tag,
1503 struct netlbl_lsm_secattr *secattr)
1504{
1505 int ret_val;
1506 u8 tag_len = tag[1];
1507 u32 level;
1508
1509 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1510 if (ret_val != 0)
1511 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001512 secattr->attr.mls.lvl = level;
Paul Moore484b3662006-11-29 13:18:20 -05001513 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
1514
1515 if (tag_len > 4) {
Paul Moore484b3662006-11-29 13:18:20 -05001516 ret_val = cipso_v4_map_cat_rng_ntoh(doi_def,
1517 &tag[4],
1518 tag_len - 4,
1519 secattr);
1520 if (ret_val != 0) {
Paul Moore4fbe63d2014-08-01 11:17:37 -04001521 netlbl_catmap_free(secattr->attr.mls.cat);
Paul Moore484b3662006-11-29 13:18:20 -05001522 return ret_val;
1523 }
1524
1525 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
1526 }
1527
1528 return 0;
1529}
1530
1531/**
Paul Moore15c45f72008-10-10 10:16:34 -04001532 * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard)
1533 * @doi_def: the DOI definition
1534 * @secattr: the security attributes
1535 * @buffer: the option buffer
1536 * @buffer_len: length of buffer in bytes
1537 *
1538 * Description:
1539 * Generate a CIPSO option using the local tag. Returns the size of the tag
1540 * on success, negative values on failure.
1541 *
1542 */
1543static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def,
1544 const struct netlbl_lsm_secattr *secattr,
1545 unsigned char *buffer,
1546 u32 buffer_len)
1547{
1548 if (!(secattr->flags & NETLBL_SECATTR_SECID))
1549 return -EPERM;
1550
1551 buffer[0] = CIPSO_V4_TAG_LOCAL;
1552 buffer[1] = CIPSO_V4_TAG_LOC_BLEN;
1553 *(u32 *)&buffer[2] = secattr->attr.secid;
1554
1555 return CIPSO_V4_TAG_LOC_BLEN;
1556}
1557
1558/**
1559 * cipso_v4_parsetag_loc - Parse a CIPSO local tag
1560 * @doi_def: the DOI definition
1561 * @tag: the CIPSO tag
1562 * @secattr: the security attributes
1563 *
1564 * Description:
1565 * Parse a CIPSO local tag and return the security attributes in @secattr.
1566 * Return zero on success, negatives values on failure.
1567 *
1568 */
1569static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def,
1570 const unsigned char *tag,
1571 struct netlbl_lsm_secattr *secattr)
1572{
1573 secattr->attr.secid = *(u32 *)&tag[2];
1574 secattr->flags |= NETLBL_SECATTR_SECID;
1575
1576 return 0;
1577}
1578
1579/**
Paul Moore446fda42006-08-03 16:48:06 -07001580 * cipso_v4_validate - Validate a CIPSO option
1581 * @option: the start of the option, on error it is set to point to the error
1582 *
1583 * Description:
1584 * This routine is called to validate a CIPSO option, it checks all of the
1585 * fields to ensure that they are at least valid, see the draft snippet below
1586 * for details. If the option is valid then a zero value is returned and
1587 * the value of @option is unchanged. If the option is invalid then a
1588 * non-zero value is returned and @option is adjusted to point to the
1589 * offending portion of the option. From the IETF draft ...
1590 *
1591 * "If any field within the CIPSO options, such as the DOI identifier, is not
1592 * recognized the IP datagram is discarded and an ICMP 'parameter problem'
1593 * (type 12) is generated and returned. The ICMP code field is set to 'bad
1594 * parameter' (code 0) and the pointer is set to the start of the CIPSO field
1595 * that is unrecognized."
1596 *
1597 */
Paul Moore15c45f72008-10-10 10:16:34 -04001598int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
Paul Moore446fda42006-08-03 16:48:06 -07001599{
1600 unsigned char *opt = *option;
1601 unsigned char *tag;
1602 unsigned char opt_iter;
1603 unsigned char err_offset = 0;
1604 u8 opt_len;
1605 u8 tag_len;
1606 struct cipso_v4_doi *doi_def = NULL;
1607 u32 tag_iter;
1608
1609 /* caller already checks for length values that are too large */
1610 opt_len = opt[1];
1611 if (opt_len < 8) {
1612 err_offset = 1;
1613 goto validate_return;
1614 }
1615
1616 rcu_read_lock();
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001617 doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2]));
Paul Moore446fda42006-08-03 16:48:06 -07001618 if (doi_def == NULL) {
1619 err_offset = 2;
1620 goto validate_return_locked;
1621 }
1622
Paul Moore15c45f72008-10-10 10:16:34 -04001623 opt_iter = CIPSO_V4_HDR_LEN;
Paul Moore446fda42006-08-03 16:48:06 -07001624 tag = opt + opt_iter;
1625 while (opt_iter < opt_len) {
1626 for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];)
1627 if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID ||
1628 ++tag_iter == CIPSO_V4_TAG_MAXCNT) {
1629 err_offset = opt_iter;
1630 goto validate_return_locked;
1631 }
1632
1633 tag_len = tag[1];
1634 if (tag_len > (opt_len - opt_iter)) {
1635 err_offset = opt_iter + 1;
1636 goto validate_return_locked;
1637 }
1638
1639 switch (tag[0]) {
1640 case CIPSO_V4_TAG_RBITMAP:
Paul Moore15c45f72008-10-10 10:16:34 -04001641 if (tag_len < CIPSO_V4_TAG_RBM_BLEN) {
Paul Moore446fda42006-08-03 16:48:06 -07001642 err_offset = opt_iter + 1;
1643 goto validate_return_locked;
1644 }
1645
1646 /* We are already going to do all the verification
1647 * necessary at the socket layer so from our point of
1648 * view it is safe to turn these checks off (and less
1649 * work), however, the CIPSO draft says we should do
1650 * all the CIPSO validations here but it doesn't
1651 * really specify _exactly_ what we need to validate
1652 * ... so, just make it a sysctl tunable. */
1653 if (cipso_v4_rbm_strictvalid) {
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 }
Paul Moore15c45f72008-10-10 10:16:34 -04001659 if (tag_len > CIPSO_V4_TAG_RBM_BLEN &&
Paul Moore446fda42006-08-03 16:48:06 -07001660 cipso_v4_map_cat_rbm_valid(doi_def,
1661 &tag[4],
1662 tag_len - 4) < 0) {
1663 err_offset = opt_iter + 4;
1664 goto validate_return_locked;
1665 }
1666 }
1667 break;
Paul Moore654bbc22006-11-29 13:18:19 -05001668 case CIPSO_V4_TAG_ENUM:
Paul Moore15c45f72008-10-10 10:16:34 -04001669 if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) {
Paul Moore654bbc22006-11-29 13:18:19 -05001670 err_offset = opt_iter + 1;
1671 goto validate_return_locked;
1672 }
1673
1674 if (cipso_v4_map_lvl_valid(doi_def,
1675 tag[3]) < 0) {
1676 err_offset = opt_iter + 3;
1677 goto validate_return_locked;
1678 }
Paul Moore15c45f72008-10-10 10:16:34 -04001679 if (tag_len > CIPSO_V4_TAG_ENUM_BLEN &&
Paul Moore654bbc22006-11-29 13:18:19 -05001680 cipso_v4_map_cat_enum_valid(doi_def,
1681 &tag[4],
1682 tag_len - 4) < 0) {
1683 err_offset = opt_iter + 4;
1684 goto validate_return_locked;
1685 }
1686 break;
Paul Moore484b3662006-11-29 13:18:20 -05001687 case CIPSO_V4_TAG_RANGE:
Paul Moore15c45f72008-10-10 10:16:34 -04001688 if (tag_len < CIPSO_V4_TAG_RNG_BLEN) {
Paul Moore484b3662006-11-29 13:18:20 -05001689 err_offset = opt_iter + 1;
1690 goto validate_return_locked;
1691 }
1692
1693 if (cipso_v4_map_lvl_valid(doi_def,
1694 tag[3]) < 0) {
1695 err_offset = opt_iter + 3;
1696 goto validate_return_locked;
1697 }
Paul Moore15c45f72008-10-10 10:16:34 -04001698 if (tag_len > CIPSO_V4_TAG_RNG_BLEN &&
Paul Moore484b3662006-11-29 13:18:20 -05001699 cipso_v4_map_cat_rng_valid(doi_def,
1700 &tag[4],
1701 tag_len - 4) < 0) {
1702 err_offset = opt_iter + 4;
1703 goto validate_return_locked;
1704 }
1705 break;
Paul Moore15c45f72008-10-10 10:16:34 -04001706 case CIPSO_V4_TAG_LOCAL:
1707 /* This is a non-standard tag that we only allow for
1708 * local connections, so if the incoming interface is
Paul Moore89d7ae32012-07-17 11:07:47 +00001709 * not the loopback device drop the packet. Further,
1710 * there is no legitimate reason for setting this from
1711 * userspace so reject it if skb is NULL. */
1712 if (skb == NULL || !(skb->dev->flags & IFF_LOOPBACK)) {
Paul Moore15c45f72008-10-10 10:16:34 -04001713 err_offset = opt_iter;
1714 goto validate_return_locked;
1715 }
1716 if (tag_len != CIPSO_V4_TAG_LOC_BLEN) {
1717 err_offset = opt_iter + 1;
1718 goto validate_return_locked;
1719 }
1720 break;
Paul Moore446fda42006-08-03 16:48:06 -07001721 default:
1722 err_offset = opt_iter;
1723 goto validate_return_locked;
1724 }
1725
1726 tag += tag_len;
1727 opt_iter += tag_len;
1728 }
1729
1730validate_return_locked:
1731 rcu_read_unlock();
1732validate_return:
1733 *option = opt + err_offset;
1734 return err_offset;
1735}
1736
1737/**
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001738 * cipso_v4_error - Send the correct response for a bad packet
Paul Moore446fda42006-08-03 16:48:06 -07001739 * @skb: the packet
1740 * @error: the error code
1741 * @gateway: CIPSO gateway flag
1742 *
1743 * Description:
1744 * Based on the error code given in @error, send an ICMP error message back to
1745 * the originating host. From the IETF draft ...
1746 *
1747 * "If the contents of the CIPSO [option] are valid but the security label is
1748 * outside of the configured host or port label range, the datagram is
1749 * discarded and an ICMP 'destination unreachable' (type 3) is generated and
1750 * returned. The code field of the ICMP is set to 'communication with
1751 * destination network administratively prohibited' (code 9) or to
1752 * 'communication with destination host administratively prohibited'
1753 * (code 10). The value of the code is dependent on whether the originator
1754 * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The
1755 * recipient of the ICMP message MUST be able to handle either value. The
1756 * same procedure is performed if a CIPSO [option] can not be added to an
1757 * IP packet because it is too large to fit in the IP options area."
1758 *
1759 * "If the error is triggered by receipt of an ICMP message, the message is
1760 * discarded and no response is permitted (consistent with general ICMP
1761 * processing rules)."
1762 *
1763 */
1764void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway)
1765{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001766 if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES)
Paul Moore446fda42006-08-03 16:48:06 -07001767 return;
1768
1769 if (gateway)
1770 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0);
1771 else
1772 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0);
1773}
1774
1775/**
Paul Moore948bf852008-10-10 10:16:32 -04001776 * cipso_v4_genopt - Generate a CIPSO option
1777 * @buf: the option buffer
1778 * @buf_len: the size of opt_buf
Paul Moore446fda42006-08-03 16:48:06 -07001779 * @doi_def: the CIPSO DOI to use
Paul Moore948bf852008-10-10 10:16:32 -04001780 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -07001781 *
1782 * Description:
Paul Moore948bf852008-10-10 10:16:32 -04001783 * Generate a CIPSO option using the DOI definition and security attributes
1784 * passed to the function. Returns the length of the option on success and
1785 * negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -07001786 *
1787 */
Paul Moore948bf852008-10-10 10:16:32 -04001788static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
1789 const struct cipso_v4_doi *doi_def,
1790 const struct netlbl_lsm_secattr *secattr)
Paul Moore446fda42006-08-03 16:48:06 -07001791{
Paul Moore948bf852008-10-10 10:16:32 -04001792 int ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001793 u32 iter;
Paul Moore446fda42006-08-03 16:48:06 -07001794
Paul Moore948bf852008-10-10 10:16:32 -04001795 if (buf_len <= CIPSO_V4_HDR_LEN)
1796 return -ENOSPC;
Paul Moore91b1ed02006-11-17 17:38:49 -05001797
Paul Moore446fda42006-08-03 16:48:06 -07001798 /* XXX - This code assumes only one tag per CIPSO option which isn't
1799 * really a good assumption to make but since we only support the MAC
1800 * tags right now it is a safe assumption. */
1801 iter = 0;
1802 do {
Paul Moore91b1ed02006-11-17 17:38:49 -05001803 memset(buf, 0, buf_len);
Paul Moore446fda42006-08-03 16:48:06 -07001804 switch (doi_def->tags[iter]) {
1805 case CIPSO_V4_TAG_RBITMAP:
1806 ret_val = cipso_v4_gentag_rbm(doi_def,
Paul Moore91b1ed02006-11-17 17:38:49 -05001807 secattr,
1808 &buf[CIPSO_V4_HDR_LEN],
1809 buf_len - CIPSO_V4_HDR_LEN);
Paul Moore446fda42006-08-03 16:48:06 -07001810 break;
Paul Moore654bbc22006-11-29 13:18:19 -05001811 case CIPSO_V4_TAG_ENUM:
1812 ret_val = cipso_v4_gentag_enum(doi_def,
1813 secattr,
1814 &buf[CIPSO_V4_HDR_LEN],
1815 buf_len - CIPSO_V4_HDR_LEN);
1816 break;
Paul Moore484b3662006-11-29 13:18:20 -05001817 case CIPSO_V4_TAG_RANGE:
1818 ret_val = cipso_v4_gentag_rng(doi_def,
1819 secattr,
1820 &buf[CIPSO_V4_HDR_LEN],
1821 buf_len - CIPSO_V4_HDR_LEN);
1822 break;
Paul Moore15c45f72008-10-10 10:16:34 -04001823 case CIPSO_V4_TAG_LOCAL:
1824 ret_val = cipso_v4_gentag_loc(doi_def,
1825 secattr,
1826 &buf[CIPSO_V4_HDR_LEN],
1827 buf_len - CIPSO_V4_HDR_LEN);
1828 break;
Paul Moore446fda42006-08-03 16:48:06 -07001829 default:
Paul Moore948bf852008-10-10 10:16:32 -04001830 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -07001831 }
1832
1833 iter++;
Paul Moore91b1ed02006-11-17 17:38:49 -05001834 } while (ret_val < 0 &&
Paul Moore446fda42006-08-03 16:48:06 -07001835 iter < CIPSO_V4_TAG_MAXCNT &&
1836 doi_def->tags[iter] != CIPSO_V4_TAG_INVALID);
Paul Moore91b1ed02006-11-17 17:38:49 -05001837 if (ret_val < 0)
Paul Moore948bf852008-10-10 10:16:32 -04001838 return ret_val;
Paul Moore91b1ed02006-11-17 17:38:49 -05001839 cipso_v4_gentag_hdr(doi_def, buf, ret_val);
Paul Moore948bf852008-10-10 10:16:32 -04001840 return CIPSO_V4_HDR_LEN + ret_val;
1841}
1842
1843/**
1844 * cipso_v4_sock_setattr - Add a CIPSO option to a socket
1845 * @sk: the socket
1846 * @doi_def: the CIPSO DOI to use
1847 * @secattr: the specific security attributes of the socket
1848 *
1849 * Description:
1850 * Set the CIPSO option on the given socket using the DOI definition and
1851 * security attributes passed to the function. This function requires
1852 * exclusive access to @sk, which means it either needs to be in the
1853 * process of being created or locked. Returns zero on success and negative
1854 * values on failure.
1855 *
1856 */
1857int cipso_v4_sock_setattr(struct sock *sk,
1858 const struct cipso_v4_doi *doi_def,
1859 const struct netlbl_lsm_secattr *secattr)
1860{
1861 int ret_val = -EPERM;
1862 unsigned char *buf = NULL;
1863 u32 buf_len;
1864 u32 opt_len;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001865 struct ip_options_rcu *old, *opt = NULL;
Paul Moore948bf852008-10-10 10:16:32 -04001866 struct inet_sock *sk_inet;
1867 struct inet_connection_sock *sk_conn;
1868
1869 /* In the case of sock_create_lite(), the sock->sk field is not
1870 * defined yet but it is not a problem as the only users of these
1871 * "lite" PF_INET sockets are functions which do an accept() call
1872 * afterwards so we will label the socket as part of the accept(). */
1873 if (sk == NULL)
1874 return 0;
1875
1876 /* We allocate the maximum CIPSO option size here so we are probably
1877 * being a little wasteful, but it makes our life _much_ easier later
1878 * on and after all we are only talking about 40 bytes. */
1879 buf_len = CIPSO_V4_OPT_LEN_MAX;
1880 buf = kmalloc(buf_len, GFP_ATOMIC);
1881 if (buf == NULL) {
1882 ret_val = -ENOMEM;
1883 goto socket_setattr_failure;
1884 }
1885
1886 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
1887 if (ret_val < 0)
1888 goto socket_setattr_failure;
1889 buf_len = ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001890
1891 /* We can't use ip_options_get() directly because it makes a call to
1892 * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
Paul Mooref8687af2006-10-30 15:22:15 -08001893 * we won't always have CAP_NET_RAW even though we _always_ want to
1894 * set the IPOPT_CIPSO option. */
Paul Moore446fda42006-08-03 16:48:06 -07001895 opt_len = (buf_len + 3) & ~3;
1896 opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
1897 if (opt == NULL) {
1898 ret_val = -ENOMEM;
1899 goto socket_setattr_failure;
1900 }
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001901 memcpy(opt->opt.__data, buf, buf_len);
1902 opt->opt.optlen = opt_len;
1903 opt->opt.cipso = sizeof(struct iphdr);
Paul Moore446fda42006-08-03 16:48:06 -07001904 kfree(buf);
1905 buf = NULL;
Paul Moore446fda42006-08-03 16:48:06 -07001906
1907 sk_inet = inet_sk(sk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001908
1909 old = rcu_dereference_protected(sk_inet->inet_opt, sock_owned_by_user(sk));
Paul Moore446fda42006-08-03 16:48:06 -07001910 if (sk_inet->is_icsk) {
1911 sk_conn = inet_csk(sk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001912 if (old)
1913 sk_conn->icsk_ext_hdr_len -= old->opt.optlen;
1914 sk_conn->icsk_ext_hdr_len += opt->opt.optlen;
Paul Moore446fda42006-08-03 16:48:06 -07001915 sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
1916 }
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001917 rcu_assign_pointer(sk_inet->inet_opt, opt);
1918 if (old)
Paul E. McKenney4f9c8c12012-01-06 17:06:11 -08001919 kfree_rcu(old, rcu);
Paul Moore446fda42006-08-03 16:48:06 -07001920
1921 return 0;
1922
1923socket_setattr_failure:
1924 kfree(buf);
1925 kfree(opt);
1926 return ret_val;
1927}
1928
1929/**
Paul Moore389fb8002009-03-27 17:10:34 -04001930 * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket
1931 * @req: the connection request socket
1932 * @doi_def: the CIPSO DOI to use
1933 * @secattr: the specific security attributes of the socket
Paul Moore014ab192008-10-10 10:16:33 -04001934 *
1935 * Description:
Paul Moore389fb8002009-03-27 17:10:34 -04001936 * Set the CIPSO option on the given socket using the DOI definition and
1937 * security attributes passed to the function. Returns zero on success and
1938 * negative values on failure.
Paul Moore014ab192008-10-10 10:16:33 -04001939 *
1940 */
Paul Moore389fb8002009-03-27 17:10:34 -04001941int cipso_v4_req_setattr(struct request_sock *req,
1942 const struct cipso_v4_doi *doi_def,
1943 const struct netlbl_lsm_secattr *secattr)
Paul Moore014ab192008-10-10 10:16:33 -04001944{
Paul Moore389fb8002009-03-27 17:10:34 -04001945 int ret_val = -EPERM;
1946 unsigned char *buf = NULL;
1947 u32 buf_len;
1948 u32 opt_len;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001949 struct ip_options_rcu *opt = NULL;
Paul Moore389fb8002009-03-27 17:10:34 -04001950 struct inet_request_sock *req_inet;
Paul Moore014ab192008-10-10 10:16:33 -04001951
Paul Moore389fb8002009-03-27 17:10:34 -04001952 /* We allocate the maximum CIPSO option size here so we are probably
1953 * being a little wasteful, but it makes our life _much_ easier later
1954 * on and after all we are only talking about 40 bytes. */
1955 buf_len = CIPSO_V4_OPT_LEN_MAX;
1956 buf = kmalloc(buf_len, GFP_ATOMIC);
1957 if (buf == NULL) {
1958 ret_val = -ENOMEM;
1959 goto req_setattr_failure;
1960 }
1961
1962 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
1963 if (ret_val < 0)
1964 goto req_setattr_failure;
1965 buf_len = ret_val;
1966
1967 /* We can't use ip_options_get() directly because it makes a call to
1968 * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
1969 * we won't always have CAP_NET_RAW even though we _always_ want to
1970 * set the IPOPT_CIPSO option. */
1971 opt_len = (buf_len + 3) & ~3;
1972 opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
1973 if (opt == NULL) {
1974 ret_val = -ENOMEM;
1975 goto req_setattr_failure;
1976 }
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001977 memcpy(opt->opt.__data, buf, buf_len);
1978 opt->opt.optlen = opt_len;
1979 opt->opt.cipso = sizeof(struct iphdr);
Paul Moore389fb8002009-03-27 17:10:34 -04001980 kfree(buf);
1981 buf = NULL;
1982
1983 req_inet = inet_rsk(req);
1984 opt = xchg(&req_inet->opt, opt);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001985 if (opt)
Paul E. McKenney4f9c8c12012-01-06 17:06:11 -08001986 kfree_rcu(opt, rcu);
Paul Moore389fb8002009-03-27 17:10:34 -04001987
1988 return 0;
1989
1990req_setattr_failure:
1991 kfree(buf);
1992 kfree(opt);
1993 return ret_val;
1994}
1995
1996/**
1997 * cipso_v4_delopt - Delete the CIPSO option from a set of IP options
1998 * @opt_ptr: IP option pointer
1999 *
2000 * Description:
2001 * Deletes the CIPSO IP option from a set of IP options and makes the necessary
2002 * adjustments to the IP option structure. Returns zero on success, negative
2003 * values on failure.
2004 *
2005 */
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002006static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr)
Paul Moore389fb8002009-03-27 17:10:34 -04002007{
2008 int hdr_delta = 0;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002009 struct ip_options_rcu *opt = *opt_ptr;
Paul Moore014ab192008-10-10 10:16:33 -04002010
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002011 if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) {
Paul Moore014ab192008-10-10 10:16:33 -04002012 u8 cipso_len;
2013 u8 cipso_off;
2014 unsigned char *cipso_ptr;
2015 int iter;
2016 int optlen_new;
2017
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002018 cipso_off = opt->opt.cipso - sizeof(struct iphdr);
2019 cipso_ptr = &opt->opt.__data[cipso_off];
Paul Moore014ab192008-10-10 10:16:33 -04002020 cipso_len = cipso_ptr[1];
2021
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002022 if (opt->opt.srr > opt->opt.cipso)
2023 opt->opt.srr -= cipso_len;
2024 if (opt->opt.rr > opt->opt.cipso)
2025 opt->opt.rr -= cipso_len;
2026 if (opt->opt.ts > opt->opt.cipso)
2027 opt->opt.ts -= cipso_len;
2028 if (opt->opt.router_alert > opt->opt.cipso)
2029 opt->opt.router_alert -= cipso_len;
2030 opt->opt.cipso = 0;
Paul Moore014ab192008-10-10 10:16:33 -04002031
2032 memmove(cipso_ptr, cipso_ptr + cipso_len,
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002033 opt->opt.optlen - cipso_off - cipso_len);
Paul Moore014ab192008-10-10 10:16:33 -04002034
2035 /* determining the new total option length is tricky because of
2036 * the padding necessary, the only thing i can think to do at
2037 * this point is walk the options one-by-one, skipping the
2038 * padding at the end to determine the actual option size and
2039 * from there we can determine the new total option length */
2040 iter = 0;
2041 optlen_new = 0;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002042 while (iter < opt->opt.optlen)
2043 if (opt->opt.__data[iter] != IPOPT_NOP) {
2044 iter += opt->opt.__data[iter + 1];
Paul Moore014ab192008-10-10 10:16:33 -04002045 optlen_new = iter;
2046 } else
2047 iter++;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002048 hdr_delta = opt->opt.optlen;
2049 opt->opt.optlen = (optlen_new + 3) & ~3;
2050 hdr_delta -= opt->opt.optlen;
Paul Moore014ab192008-10-10 10:16:33 -04002051 } else {
2052 /* only the cipso option was present on the socket so we can
2053 * remove the entire option struct */
Paul Moore389fb8002009-03-27 17:10:34 -04002054 *opt_ptr = NULL;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002055 hdr_delta = opt->opt.optlen;
Paul E. McKenney4f9c8c12012-01-06 17:06:11 -08002056 kfree_rcu(opt, rcu);
Paul Moore014ab192008-10-10 10:16:33 -04002057 }
2058
Paul Moore389fb8002009-03-27 17:10:34 -04002059 return hdr_delta;
2060}
2061
2062/**
2063 * cipso_v4_sock_delattr - Delete the CIPSO option from a socket
2064 * @sk: the socket
2065 *
2066 * Description:
2067 * Removes the CIPSO option from a socket, if present.
2068 *
2069 */
2070void cipso_v4_sock_delattr(struct sock *sk)
2071{
2072 int hdr_delta;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002073 struct ip_options_rcu *opt;
Paul Moore389fb8002009-03-27 17:10:34 -04002074 struct inet_sock *sk_inet;
2075
2076 sk_inet = inet_sk(sk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002077 opt = rcu_dereference_protected(sk_inet->inet_opt, 1);
2078 if (opt == NULL || opt->opt.cipso == 0)
Paul Moore389fb8002009-03-27 17:10:34 -04002079 return;
2080
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002081 hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt);
Paul Moore014ab192008-10-10 10:16:33 -04002082 if (sk_inet->is_icsk && hdr_delta > 0) {
2083 struct inet_connection_sock *sk_conn = inet_csk(sk);
2084 sk_conn->icsk_ext_hdr_len -= hdr_delta;
2085 sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
2086 }
2087}
2088
2089/**
Paul Moore389fb8002009-03-27 17:10:34 -04002090 * cipso_v4_req_delattr - Delete the CIPSO option from a request socket
2091 * @reg: the request socket
2092 *
2093 * Description:
2094 * Removes the CIPSO option from a request socket, if present.
2095 *
2096 */
2097void cipso_v4_req_delattr(struct request_sock *req)
2098{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002099 struct ip_options_rcu *opt;
Paul Moore389fb8002009-03-27 17:10:34 -04002100 struct inet_request_sock *req_inet;
2101
2102 req_inet = inet_rsk(req);
2103 opt = req_inet->opt;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002104 if (opt == NULL || opt->opt.cipso == 0)
Paul Moore389fb8002009-03-27 17:10:34 -04002105 return;
2106
2107 cipso_v4_delopt(&req_inet->opt);
2108}
2109
2110/**
Paul Moore63d804ea2007-09-15 21:45:13 -07002111 * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions
2112 * @cipso: the CIPSO v4 option
2113 * @secattr: the security attributes
2114 *
2115 * Description:
2116 * Inspect @cipso and return the security attributes in @secattr. Returns zero
2117 * on success and negative values on failure.
2118 *
2119 */
2120static int cipso_v4_getattr(const unsigned char *cipso,
2121 struct netlbl_lsm_secattr *secattr)
2122{
2123 int ret_val = -ENOMSG;
2124 u32 doi;
2125 struct cipso_v4_doi *doi_def;
2126
2127 if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0)
2128 return 0;
2129
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07002130 doi = get_unaligned_be32(&cipso[2]);
Paul Moore63d804ea2007-09-15 21:45:13 -07002131 rcu_read_lock();
2132 doi_def = cipso_v4_doi_search(doi);
2133 if (doi_def == NULL)
2134 goto getattr_return;
2135 /* XXX - This code assumes only one tag per CIPSO option which isn't
2136 * really a good assumption to make but since we only support the MAC
2137 * tags right now it is a safe assumption. */
2138 switch (cipso[6]) {
2139 case CIPSO_V4_TAG_RBITMAP:
2140 ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr);
2141 break;
2142 case CIPSO_V4_TAG_ENUM:
2143 ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr);
2144 break;
2145 case CIPSO_V4_TAG_RANGE:
2146 ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr);
2147 break;
Paul Moore15c45f72008-10-10 10:16:34 -04002148 case CIPSO_V4_TAG_LOCAL:
2149 ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr);
2150 break;
Paul Moore63d804ea2007-09-15 21:45:13 -07002151 }
Paul Moore16efd452008-01-29 08:37:59 -05002152 if (ret_val == 0)
2153 secattr->type = NETLBL_NLTYPE_CIPSOV4;
Paul Moore63d804ea2007-09-15 21:45:13 -07002154
2155getattr_return:
2156 rcu_read_unlock();
2157 return ret_val;
2158}
2159
2160/**
Paul Moore14a72f52006-09-25 15:52:01 -07002161 * cipso_v4_sock_getattr - Get the security attributes from a sock
2162 * @sk: the sock
2163 * @secattr: the security attributes
2164 *
2165 * Description:
2166 * Query @sk to see if there is a CIPSO option attached to the sock and if
2167 * there is return the CIPSO security attributes in @secattr. This function
2168 * requires that @sk be locked, or privately held, but it does not do any
2169 * locking itself. Returns zero on success and negative values on failure.
2170 *
2171 */
2172int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
2173{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002174 struct ip_options_rcu *opt;
2175 int res = -ENOMSG;
Paul Moore14a72f52006-09-25 15:52:01 -07002176
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002177 rcu_read_lock();
2178 opt = rcu_dereference(inet_sk(sk)->inet_opt);
2179 if (opt && opt->opt.cipso)
2180 res = cipso_v4_getattr(opt->opt.__data +
2181 opt->opt.cipso -
2182 sizeof(struct iphdr),
2183 secattr);
2184 rcu_read_unlock();
2185 return res;
Paul Moore14a72f52006-09-25 15:52:01 -07002186}
2187
2188/**
Paul Moore948bf852008-10-10 10:16:32 -04002189 * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet
2190 * @skb: the packet
2191 * @secattr: the security attributes
2192 *
2193 * Description:
2194 * Set the CIPSO option on the given packet based on the security attributes.
2195 * Returns a pointer to the IP header on success and NULL on failure.
2196 *
2197 */
2198int cipso_v4_skbuff_setattr(struct sk_buff *skb,
2199 const struct cipso_v4_doi *doi_def,
2200 const struct netlbl_lsm_secattr *secattr)
2201{
2202 int ret_val;
2203 struct iphdr *iph;
2204 struct ip_options *opt = &IPCB(skb)->opt;
2205 unsigned char buf[CIPSO_V4_OPT_LEN_MAX];
2206 u32 buf_len = CIPSO_V4_OPT_LEN_MAX;
2207 u32 opt_len;
2208 int len_delta;
2209
roel kluin00af5c62008-10-29 15:55:53 -04002210 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
2211 if (ret_val < 0)
2212 return ret_val;
2213 buf_len = ret_val;
Paul Moore948bf852008-10-10 10:16:32 -04002214 opt_len = (buf_len + 3) & ~3;
2215
2216 /* we overwrite any existing options to ensure that we have enough
2217 * room for the CIPSO option, the reason is that we _need_ to guarantee
2218 * that the security label is applied to the packet - we do the same
2219 * thing when using the socket options and it hasn't caused a problem,
2220 * if we need to we can always revisit this choice later */
2221
2222 len_delta = opt_len - opt->optlen;
2223 /* if we don't ensure enough headroom we could panic on the skb_push()
2224 * call below so make sure we have enough, we are also "mangling" the
2225 * packet so we should probably do a copy-on-write call anyway */
2226 ret_val = skb_cow(skb, skb_headroom(skb) + len_delta);
2227 if (ret_val < 0)
2228 return ret_val;
2229
2230 if (len_delta > 0) {
2231 /* we assume that the header + opt->optlen have already been
2232 * "pushed" in ip_options_build() or similar */
2233 iph = ip_hdr(skb);
2234 skb_push(skb, len_delta);
2235 memmove((char *)iph - len_delta, iph, iph->ihl << 2);
2236 skb_reset_network_header(skb);
2237 iph = ip_hdr(skb);
2238 } else if (len_delta < 0) {
2239 iph = ip_hdr(skb);
2240 memset(iph + 1, IPOPT_NOP, opt->optlen);
2241 } else
2242 iph = ip_hdr(skb);
2243
2244 if (opt->optlen > 0)
2245 memset(opt, 0, sizeof(*opt));
2246 opt->optlen = opt_len;
2247 opt->cipso = sizeof(struct iphdr);
2248 opt->is_changed = 1;
2249
2250 /* we have to do the following because we are being called from a
2251 * netfilter hook which means the packet already has had the header
2252 * fields populated and the checksum calculated - yes this means we
2253 * are doing more work than needed but we do it to keep the core
2254 * stack clean and tidy */
2255 memcpy(iph + 1, buf, buf_len);
2256 if (opt_len > buf_len)
2257 memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len);
2258 if (len_delta != 0) {
2259 iph->ihl = 5 + (opt_len >> 2);
2260 iph->tot_len = htons(skb->len);
2261 }
2262 ip_send_check(iph);
2263
2264 return 0;
2265}
2266
2267/**
2268 * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet
2269 * @skb: the packet
2270 *
2271 * Description:
2272 * Removes any and all CIPSO options from the given packet. Returns zero on
2273 * success, negative values on failure.
2274 *
2275 */
2276int cipso_v4_skbuff_delattr(struct sk_buff *skb)
2277{
2278 int ret_val;
2279 struct iphdr *iph;
2280 struct ip_options *opt = &IPCB(skb)->opt;
2281 unsigned char *cipso_ptr;
2282
2283 if (opt->cipso == 0)
2284 return 0;
2285
2286 /* since we are changing the packet we should make a copy */
2287 ret_val = skb_cow(skb, skb_headroom(skb));
2288 if (ret_val < 0)
2289 return ret_val;
2290
2291 /* the easiest thing to do is just replace the cipso option with noop
2292 * options since we don't change the size of the packet, although we
2293 * still need to recalculate the checksum */
2294
2295 iph = ip_hdr(skb);
2296 cipso_ptr = (unsigned char *)iph + opt->cipso;
2297 memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]);
2298 opt->cipso = 0;
2299 opt->is_changed = 1;
2300
2301 ip_send_check(iph);
2302
2303 return 0;
2304}
2305
2306/**
Paul Moore446fda42006-08-03 16:48:06 -07002307 * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option
2308 * @skb: the packet
2309 * @secattr: the security attributes
2310 *
2311 * Description:
2312 * Parse the given packet's CIPSO option and return the security attributes.
2313 * Returns zero on success and negative values on failure.
2314 *
2315 */
2316int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
2317 struct netlbl_lsm_secattr *secattr)
2318{
Paul Moore63d804ea2007-09-15 21:45:13 -07002319 return cipso_v4_getattr(CIPSO_V4_OPTPTR(skb), secattr);
Paul Moore446fda42006-08-03 16:48:06 -07002320}
2321
2322/*
2323 * Setup Functions
2324 */
2325
2326/**
2327 * cipso_v4_init - Initialize the CIPSO module
2328 *
2329 * Description:
2330 * Initialize the CIPSO module and prepare it for use. Returns zero on success
2331 * and negative values on failure.
2332 *
2333 */
2334static int __init cipso_v4_init(void)
2335{
2336 int ret_val;
2337
2338 ret_val = cipso_v4_cache_init();
2339 if (ret_val != 0)
2340 panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n",
2341 ret_val);
2342
2343 return 0;
2344}
2345
2346subsys_initcall(cipso_v4_init);