blob: 039cc1ffe977a5cf1073f88a9826f6798ecd26e4 [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:
12 * http://netlabel.sourceforge.net/files/draft-ietf-cipso-ipsecurity-01.txt
13 * 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
34 * along with this program; if not, write to the Free Software
35 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
36 *
37 */
38
39#include <linux/init.h>
40#include <linux/types.h>
41#include <linux/rcupdate.h>
42#include <linux/list.h>
43#include <linux/spinlock.h>
44#include <linux/string.h>
45#include <linux/jhash.h>
Paul Moore6c2e8ac2008-12-31 12:54:11 -050046#include <linux/audit.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>
paul.moore@hp.comffb733c2006-10-04 11:46:31 -040052#include <asm/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
114 * zero then it is possibile to fit 8 category ranges because the zero should
115 * 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 }
292
293 return;
294}
295
296/**
297 * cipso_v4_cache_check - Check the CIPSO cache for a label mapping
298 * @key: the buffer to check
299 * @key_len: buffer length in bytes
300 * @secattr: the security attribute struct to use
301 *
302 * Description:
303 * This function checks the cache to see if a label mapping already exists for
304 * the given key. If there is a match then the cache is adjusted and the
305 * @secattr struct is populated with the correct LSM security attributes. The
306 * cache is adjusted in the following manner if the entry is not already the
307 * first in the cache bucket:
308 *
309 * 1. The cache entry's activity counter is incremented
310 * 2. The previous (higher ranking) entry's activity counter is decremented
311 * 3. If the difference between the two activity counters is geater than
312 * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped
313 *
314 * Returns zero on success, -ENOENT for a cache miss, and other negative values
315 * on error.
316 *
317 */
318static int cipso_v4_cache_check(const unsigned char *key,
319 u32 key_len,
320 struct netlbl_lsm_secattr *secattr)
321{
322 u32 bkt;
323 struct cipso_v4_map_cache_entry *entry;
324 struct cipso_v4_map_cache_entry *prev_entry = NULL;
325 u32 hash;
326
327 if (!cipso_v4_cache_enabled)
328 return -ENOENT;
329
330 hash = cipso_v4_map_cache_hash(key, key_len);
Pavel Emelyanov5e0f8922008-05-13 23:23:55 -0700331 bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1);
Paul Moore609c92f2006-09-25 15:52:37 -0700332 spin_lock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700333 list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) {
334 if (entry->hash == hash &&
335 entry->key_len == key_len &&
336 memcmp(entry->key, key, key_len) == 0) {
337 entry->activity += 1;
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400338 atomic_inc(&entry->lsm_data->refcount);
339 secattr->cache = entry->lsm_data;
Paul Moore701a90b2006-11-17 17:38:46 -0500340 secattr->flags |= NETLBL_SECATTR_CACHE;
Paul Moore16efd452008-01-29 08:37:59 -0500341 secattr->type = NETLBL_NLTYPE_CIPSOV4;
Paul Moore446fda42006-08-03 16:48:06 -0700342 if (prev_entry == NULL) {
Paul Moore609c92f2006-09-25 15:52:37 -0700343 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700344 return 0;
345 }
346
347 if (prev_entry->activity > 0)
348 prev_entry->activity -= 1;
349 if (entry->activity > prev_entry->activity &&
350 entry->activity - prev_entry->activity >
351 CIPSO_V4_CACHE_REORDERLIMIT) {
352 __list_del(entry->list.prev, entry->list.next);
353 __list_add(&entry->list,
354 prev_entry->list.prev,
355 &prev_entry->list);
356 }
357
Paul Moore609c92f2006-09-25 15:52:37 -0700358 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700359 return 0;
360 }
361 prev_entry = entry;
362 }
Paul Moore609c92f2006-09-25 15:52:37 -0700363 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700364
365 return -ENOENT;
366}
367
368/**
369 * cipso_v4_cache_add - Add an entry to the CIPSO cache
370 * @skb: the packet
371 * @secattr: the packet's security attributes
372 *
373 * Description:
374 * Add a new entry into the CIPSO label mapping cache. Add the new entry to
375 * head of the cache bucket's list, if the cache bucket is out of room remove
376 * the last entry in the list first. It is important to note that there is
377 * currently no checking for duplicate keys. Returns zero on success,
378 * negative values on failure.
379 *
380 */
381int cipso_v4_cache_add(const struct sk_buff *skb,
382 const struct netlbl_lsm_secattr *secattr)
383{
384 int ret_val = -EPERM;
385 u32 bkt;
386 struct cipso_v4_map_cache_entry *entry = NULL;
387 struct cipso_v4_map_cache_entry *old_entry = NULL;
388 unsigned char *cipso_ptr;
389 u32 cipso_ptr_len;
390
391 if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0)
392 return 0;
393
394 cipso_ptr = CIPSO_V4_OPTPTR(skb);
395 cipso_ptr_len = cipso_ptr[1];
396
397 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
398 if (entry == NULL)
399 return -ENOMEM;
Arnaldo Carvalho de Melofac5d732006-11-17 11:14:16 -0200400 entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC);
Paul Moore446fda42006-08-03 16:48:06 -0700401 if (entry->key == NULL) {
402 ret_val = -ENOMEM;
403 goto cache_add_failure;
404 }
Paul Moore446fda42006-08-03 16:48:06 -0700405 entry->key_len = cipso_ptr_len;
406 entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len);
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400407 atomic_inc(&secattr->cache->refcount);
408 entry->lsm_data = secattr->cache;
Paul Moore446fda42006-08-03 16:48:06 -0700409
Pavel Emelyanov5e0f8922008-05-13 23:23:55 -0700410 bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1);
Paul Moore609c92f2006-09-25 15:52:37 -0700411 spin_lock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700412 if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
413 list_add(&entry->list, &cipso_v4_cache[bkt].list);
414 cipso_v4_cache[bkt].size += 1;
415 } else {
416 old_entry = list_entry(cipso_v4_cache[bkt].list.prev,
417 struct cipso_v4_map_cache_entry, list);
418 list_del(&old_entry->list);
419 list_add(&entry->list, &cipso_v4_cache[bkt].list);
420 cipso_v4_cache_entry_free(old_entry);
421 }
Paul Moore609c92f2006-09-25 15:52:37 -0700422 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700423
424 return 0;
425
426cache_add_failure:
427 if (entry)
428 cipso_v4_cache_entry_free(entry);
429 return ret_val;
430}
431
432/*
433 * DOI List Functions
434 */
435
436/**
437 * cipso_v4_doi_search - Searches for a DOI definition
438 * @doi: the DOI to search for
439 *
440 * Description:
441 * Search the DOI definition list for a DOI definition with a DOI value that
442 * matches @doi. The caller is responsibile for calling rcu_read_[un]lock().
443 * Returns a pointer to the DOI definition on success and NULL on failure.
444 */
445static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
446{
447 struct cipso_v4_doi *iter;
448
449 list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
Paul Mooreb1edeb12008-10-10 10:16:31 -0400450 if (iter->doi == doi && atomic_read(&iter->refcount))
Paul Moore446fda42006-08-03 16:48:06 -0700451 return iter;
452 return NULL;
453}
454
455/**
456 * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine
457 * @doi_def: the DOI structure
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500458 * @audit_info: NetLabel audit information
Paul Moore446fda42006-08-03 16:48:06 -0700459 *
460 * Description:
461 * The caller defines a new DOI for use by the CIPSO engine and calls this
462 * function to add it to the list of acceptable domains. The caller must
463 * ensure that the mapping table specified in @doi_def->map meets all of the
464 * requirements of the mapping type (see cipso_ipv4.h for details). Returns
465 * zero on success and non-zero on failure.
466 *
467 */
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500468int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
469 struct netlbl_audit *audit_info)
Paul Moore446fda42006-08-03 16:48:06 -0700470{
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500471 int ret_val = -EINVAL;
Paul Moore6ce61a72006-11-17 17:38:48 -0500472 u32 iter;
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500473 u32 doi;
474 u32 doi_type;
475 struct audit_buffer *audit_buf;
476
477 doi = doi_def->doi;
478 doi_type = doi_def->type;
Paul Moore6ce61a72006-11-17 17:38:48 -0500479
Paul Moore446fda42006-08-03 16:48:06 -0700480 if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500481 goto doi_add_return;
Paul Moore6ce61a72006-11-17 17:38:48 -0500482 for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) {
483 switch (doi_def->tags[iter]) {
484 case CIPSO_V4_TAG_RBITMAP:
485 break;
Paul Moore484b3662006-11-29 13:18:20 -0500486 case CIPSO_V4_TAG_RANGE:
Paul Moore654bbc22006-11-29 13:18:19 -0500487 case CIPSO_V4_TAG_ENUM:
488 if (doi_def->type != CIPSO_V4_MAP_PASS)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500489 goto doi_add_return;
Paul Moore654bbc22006-11-29 13:18:19 -0500490 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400491 case CIPSO_V4_TAG_LOCAL:
492 if (doi_def->type != CIPSO_V4_MAP_LOCAL)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500493 goto doi_add_return;
494 break;
495 case CIPSO_V4_TAG_INVALID:
496 if (iter == 0)
497 goto doi_add_return;
Paul Moore15c45f72008-10-10 10:16:34 -0400498 break;
Paul Moore6ce61a72006-11-17 17:38:48 -0500499 default:
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500500 goto doi_add_return;
Paul Moore6ce61a72006-11-17 17:38:48 -0500501 }
502 }
Paul Moore446fda42006-08-03 16:48:06 -0700503
Paul Mooreb1edeb12008-10-10 10:16:31 -0400504 atomic_set(&doi_def->refcount, 1);
Paul Moore446fda42006-08-03 16:48:06 -0700505
Paul Moore446fda42006-08-03 16:48:06 -0700506 spin_lock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500507 if (cipso_v4_doi_search(doi_def->doi) != NULL) {
508 spin_unlock(&cipso_v4_doi_list_lock);
509 ret_val = -EEXIST;
510 goto doi_add_return;
511 }
Paul Moore446fda42006-08-03 16:48:06 -0700512 list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list);
513 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500514 ret_val = 0;
Paul Moore446fda42006-08-03 16:48:06 -0700515
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500516doi_add_return:
517 audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info);
518 if (audit_buf != NULL) {
519 const char *type_str;
520 switch (doi_type) {
521 case CIPSO_V4_MAP_TRANS:
522 type_str = "trans";
523 break;
524 case CIPSO_V4_MAP_PASS:
525 type_str = "pass";
526 break;
527 case CIPSO_V4_MAP_LOCAL:
528 type_str = "local";
529 break;
530 default:
531 type_str = "(unknown)";
532 }
533 audit_log_format(audit_buf,
534 " cipso_doi=%u cipso_type=%s res=%u",
535 doi, type_str, ret_val == 0 ? 1 : 0);
536 audit_log_end(audit_buf);
537 }
Paul Moore446fda42006-08-03 16:48:06 -0700538
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500539 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700540}
541
542/**
Paul Mooreb1edeb12008-10-10 10:16:31 -0400543 * cipso_v4_doi_free - Frees a DOI definition
544 * @entry: the entry's RCU field
Paul Moore446fda42006-08-03 16:48:06 -0700545 *
546 * Description:
Paul Mooreb1edeb12008-10-10 10:16:31 -0400547 * This function frees all of the memory associated with a DOI definition.
Paul Moore446fda42006-08-03 16:48:06 -0700548 *
549 */
Paul Mooreb1edeb12008-10-10 10:16:31 -0400550void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
Paul Moore446fda42006-08-03 16:48:06 -0700551{
Paul Mooreb1edeb12008-10-10 10:16:31 -0400552 if (doi_def == NULL)
553 return;
Paul Moore446fda42006-08-03 16:48:06 -0700554
Paul Mooreb1edeb12008-10-10 10:16:31 -0400555 switch (doi_def->type) {
Paul Moore15c45f72008-10-10 10:16:34 -0400556 case CIPSO_V4_MAP_TRANS:
Paul Mooreb1edeb12008-10-10 10:16:31 -0400557 kfree(doi_def->map.std->lvl.cipso);
558 kfree(doi_def->map.std->lvl.local);
559 kfree(doi_def->map.std->cat.cipso);
560 kfree(doi_def->map.std->cat.local);
561 break;
Paul Moore446fda42006-08-03 16:48:06 -0700562 }
Paul Mooreb1edeb12008-10-10 10:16:31 -0400563 kfree(doi_def);
Paul Moore446fda42006-08-03 16:48:06 -0700564}
565
566/**
Paul Mooreb1edeb12008-10-10 10:16:31 -0400567 * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer
568 * @entry: the entry's RCU field
569 *
570 * Description:
571 * This function is designed to be used as a callback to the call_rcu()
572 * function so that the memory allocated to the DOI definition can be released
573 * safely.
574 *
575 */
576static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
577{
578 struct cipso_v4_doi *doi_def;
579
580 doi_def = container_of(entry, struct cipso_v4_doi, rcu);
581 cipso_v4_doi_free(doi_def);
582}
583
584/**
585 * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
586 * @doi: the DOI value
587 * @audit_secid: the LSM secid to use in the audit message
588 *
589 * Description:
590 * Removes a DOI definition from the CIPSO engine. The NetLabel routines will
591 * be called to release their own LSM domain mappings as well as our own
592 * domain list. Returns zero on success and negative values on failure.
593 *
594 */
595int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
596{
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500597 int ret_val;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400598 struct cipso_v4_doi *doi_def;
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500599 struct audit_buffer *audit_buf;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400600
601 spin_lock(&cipso_v4_doi_list_lock);
602 doi_def = cipso_v4_doi_search(doi);
603 if (doi_def == NULL) {
604 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500605 ret_val = -ENOENT;
606 goto doi_remove_return;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400607 }
608 if (!atomic_dec_and_test(&doi_def->refcount)) {
609 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500610 ret_val = -EBUSY;
611 goto doi_remove_return;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400612 }
613 list_del_rcu(&doi_def->list);
614 spin_unlock(&cipso_v4_doi_list_lock);
615
616 cipso_v4_cache_invalidate();
617 call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500618 ret_val = 0;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400619
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500620doi_remove_return:
621 audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info);
622 if (audit_buf != NULL) {
623 audit_log_format(audit_buf,
624 " cipso_doi=%u res=%u",
625 doi, ret_val == 0 ? 1 : 0);
626 audit_log_end(audit_buf);
627 }
628
629 return ret_val;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400630}
631
632/**
633 * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition
Paul Moore446fda42006-08-03 16:48:06 -0700634 * @doi: the DOI value
635 *
636 * Description:
637 * Searches for a valid DOI definition and if one is found it is returned to
638 * the caller. Otherwise NULL is returned. The caller must ensure that
Paul Mooreb1edeb12008-10-10 10:16:31 -0400639 * rcu_read_lock() is held while accessing the returned definition and the DOI
640 * definition reference count is decremented when the caller is done.
Paul Moore446fda42006-08-03 16:48:06 -0700641 *
642 */
643struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
644{
Paul Mooreb1edeb12008-10-10 10:16:31 -0400645 struct cipso_v4_doi *doi_def;
646
647 rcu_read_lock();
648 doi_def = cipso_v4_doi_search(doi);
649 if (doi_def == NULL)
650 goto doi_getdef_return;
651 if (!atomic_inc_not_zero(&doi_def->refcount))
652 doi_def = NULL;
653
654doi_getdef_return:
655 rcu_read_unlock();
656 return doi_def;
657}
658
659/**
660 * cipso_v4_doi_putdef - Releases a reference for the given DOI definition
661 * @doi_def: the DOI definition
662 *
663 * Description:
664 * Releases a DOI definition reference obtained from cipso_v4_doi_getdef().
665 *
666 */
667void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
668{
669 if (doi_def == NULL)
670 return;
671
672 if (!atomic_dec_and_test(&doi_def->refcount))
673 return;
674 spin_lock(&cipso_v4_doi_list_lock);
675 list_del_rcu(&doi_def->list);
676 spin_unlock(&cipso_v4_doi_list_lock);
677
678 cipso_v4_cache_invalidate();
679 call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
Paul Moore446fda42006-08-03 16:48:06 -0700680}
681
682/**
Paul Moorefcd48282006-09-25 15:56:09 -0700683 * cipso_v4_doi_walk - Iterate through the DOI definitions
684 * @skip_cnt: skip past this number of DOI definitions, updated
685 * @callback: callback for each DOI definition
686 * @cb_arg: argument for the callback function
Paul Moore446fda42006-08-03 16:48:06 -0700687 *
688 * Description:
Paul Moorefcd48282006-09-25 15:56:09 -0700689 * Iterate over the DOI definition list, skipping the first @skip_cnt entries.
690 * For each entry call @callback, if @callback returns a negative value stop
691 * 'walking' through the list and return. Updates the value in @skip_cnt upon
692 * return. Returns zero on success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -0700693 *
694 */
Paul Moorefcd48282006-09-25 15:56:09 -0700695int cipso_v4_doi_walk(u32 *skip_cnt,
696 int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
697 void *cb_arg)
Paul Moore446fda42006-08-03 16:48:06 -0700698{
Paul Moorefcd48282006-09-25 15:56:09 -0700699 int ret_val = -ENOENT;
Paul Moore446fda42006-08-03 16:48:06 -0700700 u32 doi_cnt = 0;
Paul Moorefcd48282006-09-25 15:56:09 -0700701 struct cipso_v4_doi *iter_doi;
Paul Moore446fda42006-08-03 16:48:06 -0700702
703 rcu_read_lock();
Paul Moorefcd48282006-09-25 15:56:09 -0700704 list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
Paul Mooreb1edeb12008-10-10 10:16:31 -0400705 if (atomic_read(&iter_doi->refcount) > 0) {
Paul Moorefcd48282006-09-25 15:56:09 -0700706 if (doi_cnt++ < *skip_cnt)
707 continue;
708 ret_val = callback(iter_doi, cb_arg);
709 if (ret_val < 0) {
710 doi_cnt--;
711 goto doi_walk_return;
Paul Moore446fda42006-08-03 16:48:06 -0700712 }
Paul Moorefcd48282006-09-25 15:56:09 -0700713 }
Paul Moore446fda42006-08-03 16:48:06 -0700714
Paul Moorefcd48282006-09-25 15:56:09 -0700715doi_walk_return:
Paul Moore446fda42006-08-03 16:48:06 -0700716 rcu_read_unlock();
Paul Moorefcd48282006-09-25 15:56:09 -0700717 *skip_cnt = doi_cnt;
718 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700719}
720
Paul Moore446fda42006-08-03 16:48:06 -0700721/*
722 * Label Mapping Functions
723 */
724
725/**
726 * cipso_v4_map_lvl_valid - Checks to see if the given level is understood
727 * @doi_def: the DOI definition
728 * @level: the level to check
729 *
730 * Description:
731 * Checks the given level against the given DOI definition and returns a
732 * negative value if the level does not have a valid mapping and a zero value
733 * if the level is defined by the DOI.
734 *
735 */
736static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level)
737{
738 switch (doi_def->type) {
739 case CIPSO_V4_MAP_PASS:
740 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400741 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700742 if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)
743 return 0;
744 break;
745 }
746
747 return -EFAULT;
748}
749
750/**
751 * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network
752 * @doi_def: the DOI definition
753 * @host_lvl: the host MLS level
754 * @net_lvl: the network/CIPSO MLS level
755 *
756 * Description:
757 * Perform a label mapping to translate a local MLS level to the correct
758 * CIPSO level using the given DOI definition. Returns zero on success,
759 * negative values otherwise.
760 *
761 */
762static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def,
763 u32 host_lvl,
764 u32 *net_lvl)
765{
766 switch (doi_def->type) {
767 case CIPSO_V4_MAP_PASS:
768 *net_lvl = host_lvl;
769 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400770 case CIPSO_V4_MAP_TRANS:
Paul Moorec6387a82007-03-02 13:19:02 -0800771 if (host_lvl < doi_def->map.std->lvl.local_size &&
772 doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) {
Paul Moore446fda42006-08-03 16:48:06 -0700773 *net_lvl = doi_def->map.std->lvl.local[host_lvl];
774 return 0;
775 }
Paul Moorec6387a82007-03-02 13:19:02 -0800776 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700777 }
778
779 return -EINVAL;
780}
781
782/**
783 * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host
784 * @doi_def: the DOI definition
785 * @net_lvl: the network/CIPSO MLS level
786 * @host_lvl: the host MLS level
787 *
788 * Description:
789 * Perform a label mapping to translate a CIPSO level to the correct local MLS
790 * level using the given DOI definition. Returns zero on success, negative
791 * values otherwise.
792 *
793 */
794static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def,
795 u32 net_lvl,
796 u32 *host_lvl)
797{
798 struct cipso_v4_std_map_tbl *map_tbl;
799
800 switch (doi_def->type) {
801 case CIPSO_V4_MAP_PASS:
802 *host_lvl = net_lvl;
803 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400804 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700805 map_tbl = doi_def->map.std;
806 if (net_lvl < map_tbl->lvl.cipso_size &&
807 map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) {
808 *host_lvl = doi_def->map.std->lvl.cipso[net_lvl];
809 return 0;
810 }
Paul Moorec6387a82007-03-02 13:19:02 -0800811 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700812 }
813
814 return -EINVAL;
815}
816
817/**
818 * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid
819 * @doi_def: the DOI definition
820 * @bitmap: category bitmap
821 * @bitmap_len: bitmap length in bytes
822 *
823 * Description:
824 * Checks the given category bitmap against the given DOI definition and
825 * returns a negative value if any of the categories in the bitmap do not have
826 * a valid mapping and a zero value if all of the categories are valid.
827 *
828 */
829static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def,
830 const unsigned char *bitmap,
831 u32 bitmap_len)
832{
833 int cat = -1;
834 u32 bitmap_len_bits = bitmap_len * 8;
Paul Moore044a68e2006-10-11 19:10:47 -0400835 u32 cipso_cat_size;
836 u32 *cipso_array;
Paul Moore446fda42006-08-03 16:48:06 -0700837
838 switch (doi_def->type) {
839 case CIPSO_V4_MAP_PASS:
840 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400841 case CIPSO_V4_MAP_TRANS:
Paul Moore044a68e2006-10-11 19:10:47 -0400842 cipso_cat_size = doi_def->map.std->cat.cipso_size;
843 cipso_array = doi_def->map.std->cat.cipso;
Paul Moore446fda42006-08-03 16:48:06 -0700844 for (;;) {
845 cat = cipso_v4_bitmap_walk(bitmap,
846 bitmap_len_bits,
847 cat + 1,
848 1);
849 if (cat < 0)
850 break;
851 if (cat >= cipso_cat_size ||
852 cipso_array[cat] >= CIPSO_V4_INV_CAT)
853 return -EFAULT;
854 }
855
856 if (cat == -1)
857 return 0;
858 break;
859 }
860
861 return -EFAULT;
862}
863
864/**
865 * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network
866 * @doi_def: the DOI definition
Paul Moore02752762006-11-29 13:18:18 -0500867 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -0700868 * @net_cat: the zero'd out category bitmap in network/CIPSO format
869 * @net_cat_len: the length of the CIPSO bitmap in bytes
870 *
871 * Description:
872 * Perform a label mapping to translate a local MLS category bitmap to the
873 * correct CIPSO bitmap using the given DOI definition. Returns the minimum
874 * size in bytes of the network bitmap on success, negative values otherwise.
875 *
876 */
877static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def,
Paul Moore02752762006-11-29 13:18:18 -0500878 const struct netlbl_lsm_secattr *secattr,
Paul Moore446fda42006-08-03 16:48:06 -0700879 unsigned char *net_cat,
880 u32 net_cat_len)
881{
882 int host_spot = -1;
Paul Moore02752762006-11-29 13:18:18 -0500883 u32 net_spot = CIPSO_V4_INV_CAT;
Paul Moore446fda42006-08-03 16:48:06 -0700884 u32 net_spot_max = 0;
Paul Moore446fda42006-08-03 16:48:06 -0700885 u32 net_clen_bits = net_cat_len * 8;
Paul Moore02752762006-11-29 13:18:18 -0500886 u32 host_cat_size = 0;
887 u32 *host_cat_array = NULL;
Paul Moore446fda42006-08-03 16:48:06 -0700888
Paul Moore15c45f72008-10-10 10:16:34 -0400889 if (doi_def->type == CIPSO_V4_MAP_TRANS) {
Paul Moore044a68e2006-10-11 19:10:47 -0400890 host_cat_size = doi_def->map.std->cat.local_size;
891 host_cat_array = doi_def->map.std->cat.local;
Paul Moore02752762006-11-29 13:18:18 -0500892 }
893
894 for (;;) {
Paul Moore16efd452008-01-29 08:37:59 -0500895 host_spot = netlbl_secattr_catmap_walk(secattr->attr.mls.cat,
Paul Moore02752762006-11-29 13:18:18 -0500896 host_spot + 1);
897 if (host_spot < 0)
898 break;
899
900 switch (doi_def->type) {
901 case CIPSO_V4_MAP_PASS:
902 net_spot = host_spot;
903 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400904 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700905 if (host_spot >= host_cat_size)
906 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700907 net_spot = host_cat_array[host_spot];
Paul Moore9fade4b2006-11-17 17:38:50 -0500908 if (net_spot >= CIPSO_V4_INV_CAT)
909 return -EPERM;
Paul Moore02752762006-11-29 13:18:18 -0500910 break;
Paul Moore446fda42006-08-03 16:48:06 -0700911 }
Paul Moore02752762006-11-29 13:18:18 -0500912 if (net_spot >= net_clen_bits)
913 return -ENOSPC;
914 cipso_v4_bitmap_setbit(net_cat, net_spot, 1);
Paul Moore446fda42006-08-03 16:48:06 -0700915
Paul Moore02752762006-11-29 13:18:18 -0500916 if (net_spot > net_spot_max)
917 net_spot_max = net_spot;
Paul Moore446fda42006-08-03 16:48:06 -0700918 }
919
Paul Moore02752762006-11-29 13:18:18 -0500920 if (++net_spot_max % 8)
921 return net_spot_max / 8 + 1;
922 return net_spot_max / 8;
Paul Moore446fda42006-08-03 16:48:06 -0700923}
924
925/**
926 * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host
927 * @doi_def: the DOI definition
928 * @net_cat: the category bitmap in network/CIPSO format
929 * @net_cat_len: the length of the CIPSO bitmap in bytes
Paul Moore02752762006-11-29 13:18:18 -0500930 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -0700931 *
932 * Description:
933 * Perform a label mapping to translate a CIPSO bitmap to the correct local
Paul Moore02752762006-11-29 13:18:18 -0500934 * MLS category bitmap using the given DOI definition. Returns zero on
935 * success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -0700936 *
937 */
938static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
939 const unsigned char *net_cat,
940 u32 net_cat_len,
Paul Moore02752762006-11-29 13:18:18 -0500941 struct netlbl_lsm_secattr *secattr)
Paul Moore446fda42006-08-03 16:48:06 -0700942{
Paul Moore02752762006-11-29 13:18:18 -0500943 int ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700944 int net_spot = -1;
Paul Moore02752762006-11-29 13:18:18 -0500945 u32 host_spot = CIPSO_V4_INV_CAT;
Paul Moore446fda42006-08-03 16:48:06 -0700946 u32 net_clen_bits = net_cat_len * 8;
Paul Moore02752762006-11-29 13:18:18 -0500947 u32 net_cat_size = 0;
948 u32 *net_cat_array = NULL;
Paul Moore446fda42006-08-03 16:48:06 -0700949
Paul Moore15c45f72008-10-10 10:16:34 -0400950 if (doi_def->type == CIPSO_V4_MAP_TRANS) {
Paul Moore044a68e2006-10-11 19:10:47 -0400951 net_cat_size = doi_def->map.std->cat.cipso_size;
952 net_cat_array = doi_def->map.std->cat.cipso;
Paul Moore02752762006-11-29 13:18:18 -0500953 }
Paul Moore446fda42006-08-03 16:48:06 -0700954
Paul Moore02752762006-11-29 13:18:18 -0500955 for (;;) {
956 net_spot = cipso_v4_bitmap_walk(net_cat,
957 net_clen_bits,
958 net_spot + 1,
959 1);
960 if (net_spot < 0) {
961 if (net_spot == -2)
962 return -EFAULT;
963 return 0;
964 }
965
966 switch (doi_def->type) {
967 case CIPSO_V4_MAP_PASS:
968 host_spot = net_spot;
969 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400970 case CIPSO_V4_MAP_TRANS:
Paul Moore02752762006-11-29 13:18:18 -0500971 if (net_spot >= net_cat_size)
972 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700973 host_spot = net_cat_array[net_spot];
Paul Moore9fade4b2006-11-17 17:38:50 -0500974 if (host_spot >= CIPSO_V4_INV_CAT)
975 return -EPERM;
Paul Moore02752762006-11-29 13:18:18 -0500976 break;
Paul Moore446fda42006-08-03 16:48:06 -0700977 }
Paul Moore16efd452008-01-29 08:37:59 -0500978 ret_val = netlbl_secattr_catmap_setbit(secattr->attr.mls.cat,
Paul Moore02752762006-11-29 13:18:18 -0500979 host_spot,
980 GFP_ATOMIC);
981 if (ret_val != 0)
982 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700983 }
984
985 return -EINVAL;
986}
987
Paul Moore654bbc22006-11-29 13:18:19 -0500988/**
989 * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid
990 * @doi_def: the DOI definition
991 * @enumcat: category list
992 * @enumcat_len: length of the category list in bytes
993 *
994 * Description:
995 * Checks the given categories against the given DOI definition and returns a
996 * negative value if any of the categories do not have a valid mapping and a
997 * zero value if all of the categories are valid.
998 *
999 */
1000static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def,
1001 const unsigned char *enumcat,
1002 u32 enumcat_len)
1003{
1004 u16 cat;
1005 int cat_prev = -1;
1006 u32 iter;
1007
1008 if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01)
1009 return -EFAULT;
1010
1011 for (iter = 0; iter < enumcat_len; iter += 2) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001012 cat = get_unaligned_be16(&enumcat[iter]);
Paul Moore654bbc22006-11-29 13:18:19 -05001013 if (cat <= cat_prev)
1014 return -EFAULT;
1015 cat_prev = cat;
1016 }
1017
1018 return 0;
1019}
1020
1021/**
1022 * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network
1023 * @doi_def: the DOI definition
1024 * @secattr: the security attributes
1025 * @net_cat: the zero'd out category list in network/CIPSO format
1026 * @net_cat_len: the length of the CIPSO category list in bytes
1027 *
1028 * Description:
1029 * Perform a label mapping to translate a local MLS category bitmap to the
1030 * correct CIPSO category list using the given DOI definition. Returns the
1031 * size in bytes of the network category bitmap on success, negative values
1032 * otherwise.
1033 *
1034 */
1035static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def,
1036 const struct netlbl_lsm_secattr *secattr,
1037 unsigned char *net_cat,
1038 u32 net_cat_len)
1039{
1040 int cat = -1;
1041 u32 cat_iter = 0;
1042
1043 for (;;) {
Paul Moore16efd452008-01-29 08:37:59 -05001044 cat = netlbl_secattr_catmap_walk(secattr->attr.mls.cat,
1045 cat + 1);
Paul Moore654bbc22006-11-29 13:18:19 -05001046 if (cat < 0)
1047 break;
1048 if ((cat_iter + 2) > net_cat_len)
1049 return -ENOSPC;
1050
1051 *((__be16 *)&net_cat[cat_iter]) = htons(cat);
1052 cat_iter += 2;
1053 }
1054
1055 return cat_iter;
1056}
1057
1058/**
1059 * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host
1060 * @doi_def: the DOI definition
1061 * @net_cat: the category list in network/CIPSO format
1062 * @net_cat_len: the length of the CIPSO bitmap in bytes
1063 * @secattr: the security attributes
1064 *
1065 * Description:
1066 * Perform a label mapping to translate a CIPSO category list to the correct
1067 * local MLS category bitmap using the given DOI definition. Returns zero on
1068 * success, negative values on failure.
1069 *
1070 */
1071static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def,
1072 const unsigned char *net_cat,
1073 u32 net_cat_len,
1074 struct netlbl_lsm_secattr *secattr)
1075{
1076 int ret_val;
1077 u32 iter;
1078
1079 for (iter = 0; iter < net_cat_len; iter += 2) {
Paul Moore16efd452008-01-29 08:37:59 -05001080 ret_val = netlbl_secattr_catmap_setbit(secattr->attr.mls.cat,
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001081 get_unaligned_be16(&net_cat[iter]),
Paul Moore50e5d352007-06-07 18:38:14 -07001082 GFP_ATOMIC);
Paul Moore654bbc22006-11-29 13:18:19 -05001083 if (ret_val != 0)
1084 return ret_val;
1085 }
1086
1087 return 0;
1088}
1089
Paul Moore484b3662006-11-29 13:18:20 -05001090/**
1091 * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid
1092 * @doi_def: the DOI definition
1093 * @rngcat: category list
1094 * @rngcat_len: length of the category list in bytes
1095 *
1096 * Description:
1097 * Checks the given categories against the given DOI definition and returns a
1098 * negative value if any of the categories do not have a valid mapping and a
1099 * zero value if all of the categories are valid.
1100 *
1101 */
1102static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def,
1103 const unsigned char *rngcat,
1104 u32 rngcat_len)
1105{
1106 u16 cat_high;
1107 u16 cat_low;
1108 u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1;
1109 u32 iter;
1110
1111 if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01)
1112 return -EFAULT;
1113
1114 for (iter = 0; iter < rngcat_len; iter += 4) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001115 cat_high = get_unaligned_be16(&rngcat[iter]);
Paul Moore484b3662006-11-29 13:18:20 -05001116 if ((iter + 4) <= rngcat_len)
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001117 cat_low = get_unaligned_be16(&rngcat[iter + 2]);
Paul Moore484b3662006-11-29 13:18:20 -05001118 else
1119 cat_low = 0;
1120
1121 if (cat_high > cat_prev)
1122 return -EFAULT;
1123
1124 cat_prev = cat_low;
1125 }
1126
1127 return 0;
1128}
1129
1130/**
1131 * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network
1132 * @doi_def: the DOI definition
1133 * @secattr: the security attributes
1134 * @net_cat: the zero'd out category list in network/CIPSO format
1135 * @net_cat_len: the length of the CIPSO category list in bytes
1136 *
1137 * Description:
1138 * Perform a label mapping to translate a local MLS category bitmap to the
1139 * correct CIPSO category list using the given DOI definition. Returns the
1140 * size in bytes of the network category bitmap on success, negative values
1141 * otherwise.
1142 *
1143 */
1144static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def,
1145 const struct netlbl_lsm_secattr *secattr,
1146 unsigned char *net_cat,
1147 u32 net_cat_len)
1148{
Paul Moore484b3662006-11-29 13:18:20 -05001149 int iter = -1;
Paul Mooref998e8c2007-02-28 15:14:20 -05001150 u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2];
Paul Moore484b3662006-11-29 13:18:20 -05001151 u32 array_cnt = 0;
1152 u32 cat_size = 0;
1153
Paul Mooref998e8c2007-02-28 15:14:20 -05001154 /* make sure we don't overflow the 'array[]' variable */
Paul Moore128c6b62007-02-28 15:14:21 -05001155 if (net_cat_len >
1156 (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN))
1157 return -ENOSPC;
Paul Moore484b3662006-11-29 13:18:20 -05001158
1159 for (;;) {
Paul Moore16efd452008-01-29 08:37:59 -05001160 iter = netlbl_secattr_catmap_walk(secattr->attr.mls.cat,
1161 iter + 1);
Paul Moore484b3662006-11-29 13:18:20 -05001162 if (iter < 0)
1163 break;
1164 cat_size += (iter == 0 ? 0 : sizeof(u16));
1165 if (cat_size > net_cat_len)
1166 return -ENOSPC;
1167 array[array_cnt++] = iter;
1168
Paul Moore16efd452008-01-29 08:37:59 -05001169 iter = netlbl_secattr_catmap_walk_rng(secattr->attr.mls.cat,
1170 iter);
Paul Moore484b3662006-11-29 13:18:20 -05001171 if (iter < 0)
1172 return -EFAULT;
1173 cat_size += sizeof(u16);
1174 if (cat_size > net_cat_len)
1175 return -ENOSPC;
1176 array[array_cnt++] = iter;
1177 }
1178
1179 for (iter = 0; array_cnt > 0;) {
1180 *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]);
1181 iter += 2;
1182 array_cnt--;
1183 if (array[array_cnt] != 0) {
1184 *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]);
1185 iter += 2;
1186 }
1187 }
1188
1189 return cat_size;
1190}
1191
1192/**
1193 * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host
1194 * @doi_def: the DOI definition
1195 * @net_cat: the category list in network/CIPSO format
1196 * @net_cat_len: the length of the CIPSO bitmap in bytes
1197 * @secattr: the security attributes
1198 *
1199 * Description:
1200 * Perform a label mapping to translate a CIPSO category list to the correct
1201 * local MLS category bitmap using the given DOI definition. Returns zero on
1202 * success, negative values on failure.
1203 *
1204 */
1205static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def,
1206 const unsigned char *net_cat,
1207 u32 net_cat_len,
1208 struct netlbl_lsm_secattr *secattr)
1209{
1210 int ret_val;
1211 u32 net_iter;
1212 u16 cat_low;
1213 u16 cat_high;
1214
Stephen Hemminger132adf52007-03-08 20:44:43 -08001215 for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001216 cat_high = get_unaligned_be16(&net_cat[net_iter]);
Paul Moore484b3662006-11-29 13:18:20 -05001217 if ((net_iter + 4) <= net_cat_len)
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001218 cat_low = get_unaligned_be16(&net_cat[net_iter + 2]);
Paul Moore484b3662006-11-29 13:18:20 -05001219 else
1220 cat_low = 0;
1221
Paul Moore16efd452008-01-29 08:37:59 -05001222 ret_val = netlbl_secattr_catmap_setrng(secattr->attr.mls.cat,
Paul Moore484b3662006-11-29 13:18:20 -05001223 cat_low,
1224 cat_high,
1225 GFP_ATOMIC);
1226 if (ret_val != 0)
1227 return ret_val;
1228 }
1229
1230 return 0;
1231}
1232
Paul Moore446fda42006-08-03 16:48:06 -07001233/*
1234 * Protocol Handling Functions
1235 */
1236
Paul Moore446fda42006-08-03 16:48:06 -07001237/**
1238 * cipso_v4_gentag_hdr - Generate a CIPSO option header
1239 * @doi_def: the DOI definition
Paul Moore91b1ed02006-11-17 17:38:49 -05001240 * @len: the total tag length in bytes, not including this header
Paul Moore446fda42006-08-03 16:48:06 -07001241 * @buf: the CIPSO option buffer
1242 *
1243 * Description:
Paul Moore91b1ed02006-11-17 17:38:49 -05001244 * Write a CIPSO header into the beginning of @buffer.
Paul Moore446fda42006-08-03 16:48:06 -07001245 *
1246 */
Paul Moore91b1ed02006-11-17 17:38:49 -05001247static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def,
1248 unsigned char *buf,
1249 u32 len)
Paul Moore446fda42006-08-03 16:48:06 -07001250{
Paul Moore446fda42006-08-03 16:48:06 -07001251 buf[0] = IPOPT_CIPSO;
1252 buf[1] = CIPSO_V4_HDR_LEN + len;
Al Viro714e85b2006-11-14 20:51:49 -08001253 *(__be32 *)&buf[2] = htonl(doi_def->doi);
Paul Moore446fda42006-08-03 16:48:06 -07001254}
1255
Paul Moore446fda42006-08-03 16:48:06 -07001256/**
1257 * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1)
1258 * @doi_def: the DOI definition
1259 * @secattr: the security attributes
1260 * @buffer: the option buffer
1261 * @buffer_len: length of buffer in bytes
1262 *
1263 * Description:
1264 * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The
1265 * actual buffer length may be larger than the indicated size due to
Paul Moore91b1ed02006-11-17 17:38:49 -05001266 * translation between host and network category bitmaps. Returns the size of
1267 * the tag on success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -07001268 *
1269 */
1270static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
1271 const struct netlbl_lsm_secattr *secattr,
Paul Moore91b1ed02006-11-17 17:38:49 -05001272 unsigned char *buffer,
1273 u32 buffer_len)
Paul Moore446fda42006-08-03 16:48:06 -07001274{
Paul Moore701a90b2006-11-17 17:38:46 -05001275 int ret_val;
Paul Moore91b1ed02006-11-17 17:38:49 -05001276 u32 tag_len;
Paul Moore446fda42006-08-03 16:48:06 -07001277 u32 level;
1278
Paul Moore701a90b2006-11-17 17:38:46 -05001279 if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0)
1280 return -EPERM;
1281
Paul Moore16efd452008-01-29 08:37:59 -05001282 ret_val = cipso_v4_map_lvl_hton(doi_def,
1283 secattr->attr.mls.lvl,
1284 &level);
Paul Moore91b1ed02006-11-17 17:38:49 -05001285 if (ret_val != 0)
1286 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001287
Paul Moore91b1ed02006-11-17 17:38:49 -05001288 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
Paul Moore446fda42006-08-03 16:48:06 -07001289 ret_val = cipso_v4_map_cat_rbm_hton(doi_def,
Paul Moore02752762006-11-29 13:18:18 -05001290 secattr,
Paul Moore91b1ed02006-11-17 17:38:49 -05001291 &buffer[4],
1292 buffer_len - 4);
Paul Moore446fda42006-08-03 16:48:06 -07001293 if (ret_val < 0)
Paul Moore91b1ed02006-11-17 17:38:49 -05001294 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001295
1296 /* This will send packets using the "optimized" format when
1297 * possibile as specified in section 3.4.2.6 of the
1298 * CIPSO draft. */
Paul Moore701a90b2006-11-17 17:38:46 -05001299 if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
Paul Moore91b1ed02006-11-17 17:38:49 -05001300 tag_len = 14;
Paul Moore701a90b2006-11-17 17:38:46 -05001301 else
Paul Moore91b1ed02006-11-17 17:38:49 -05001302 tag_len = 4 + ret_val;
1303 } else
1304 tag_len = 4;
Paul Moore446fda42006-08-03 16:48:06 -07001305
Paul Moore15c45f72008-10-10 10:16:34 -04001306 buffer[0] = CIPSO_V4_TAG_RBITMAP;
Paul Moore91b1ed02006-11-17 17:38:49 -05001307 buffer[1] = tag_len;
1308 buffer[3] = level;
Paul Moore446fda42006-08-03 16:48:06 -07001309
Paul Moore91b1ed02006-11-17 17:38:49 -05001310 return tag_len;
Paul Moore446fda42006-08-03 16:48:06 -07001311}
1312
1313/**
1314 * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag
1315 * @doi_def: the DOI definition
1316 * @tag: the CIPSO tag
1317 * @secattr: the security attributes
1318 *
1319 * Description:
1320 * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security
1321 * attributes in @secattr. Return zero on success, negatives values on
1322 * failure.
1323 *
1324 */
1325static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def,
1326 const unsigned char *tag,
1327 struct netlbl_lsm_secattr *secattr)
1328{
1329 int ret_val;
1330 u8 tag_len = tag[1];
1331 u32 level;
1332
1333 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1334 if (ret_val != 0)
1335 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001336 secattr->attr.mls.lvl = level;
Paul Moore701a90b2006-11-17 17:38:46 -05001337 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
Paul Moore446fda42006-08-03 16:48:06 -07001338
1339 if (tag_len > 4) {
Paul Moore16efd452008-01-29 08:37:59 -05001340 secattr->attr.mls.cat =
1341 netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1342 if (secattr->attr.mls.cat == NULL)
Paul Moore446fda42006-08-03 16:48:06 -07001343 return -ENOMEM;
1344
1345 ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def,
1346 &tag[4],
1347 tag_len - 4,
Paul Moore02752762006-11-29 13:18:18 -05001348 secattr);
1349 if (ret_val != 0) {
Paul Moore16efd452008-01-29 08:37:59 -05001350 netlbl_secattr_catmap_free(secattr->attr.mls.cat);
Paul Moore446fda42006-08-03 16:48:06 -07001351 return ret_val;
1352 }
Paul Moore02752762006-11-29 13:18:18 -05001353
1354 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
Paul Moore446fda42006-08-03 16:48:06 -07001355 }
1356
1357 return 0;
1358}
1359
1360/**
Paul Moore654bbc22006-11-29 13:18:19 -05001361 * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2)
1362 * @doi_def: the DOI definition
1363 * @secattr: the security attributes
1364 * @buffer: the option buffer
1365 * @buffer_len: length of buffer in bytes
1366 *
1367 * Description:
1368 * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the
1369 * size of the tag on success, negative values on failure.
1370 *
1371 */
1372static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def,
1373 const struct netlbl_lsm_secattr *secattr,
1374 unsigned char *buffer,
1375 u32 buffer_len)
1376{
1377 int ret_val;
1378 u32 tag_len;
1379 u32 level;
1380
1381 if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL))
1382 return -EPERM;
1383
Paul Moore16efd452008-01-29 08:37:59 -05001384 ret_val = cipso_v4_map_lvl_hton(doi_def,
1385 secattr->attr.mls.lvl,
1386 &level);
Paul Moore654bbc22006-11-29 13:18:19 -05001387 if (ret_val != 0)
1388 return ret_val;
1389
1390 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
1391 ret_val = cipso_v4_map_cat_enum_hton(doi_def,
1392 secattr,
1393 &buffer[4],
1394 buffer_len - 4);
1395 if (ret_val < 0)
1396 return ret_val;
1397
1398 tag_len = 4 + ret_val;
1399 } else
1400 tag_len = 4;
1401
Paul Moore15c45f72008-10-10 10:16:34 -04001402 buffer[0] = CIPSO_V4_TAG_ENUM;
Paul Moore654bbc22006-11-29 13:18:19 -05001403 buffer[1] = tag_len;
1404 buffer[3] = level;
1405
1406 return tag_len;
1407}
1408
1409/**
1410 * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag
1411 * @doi_def: the DOI definition
1412 * @tag: the CIPSO tag
1413 * @secattr: the security attributes
1414 *
1415 * Description:
1416 * Parse a CIPSO enumerated tag (tag type #2) and return the security
1417 * attributes in @secattr. Return zero on success, negatives values on
1418 * failure.
1419 *
1420 */
1421static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def,
1422 const unsigned char *tag,
1423 struct netlbl_lsm_secattr *secattr)
1424{
1425 int ret_val;
1426 u8 tag_len = tag[1];
1427 u32 level;
1428
1429 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1430 if (ret_val != 0)
1431 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001432 secattr->attr.mls.lvl = level;
Paul Moore654bbc22006-11-29 13:18:19 -05001433 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
1434
1435 if (tag_len > 4) {
Paul Moore16efd452008-01-29 08:37:59 -05001436 secattr->attr.mls.cat =
1437 netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1438 if (secattr->attr.mls.cat == NULL)
Paul Moore654bbc22006-11-29 13:18:19 -05001439 return -ENOMEM;
1440
1441 ret_val = cipso_v4_map_cat_enum_ntoh(doi_def,
1442 &tag[4],
1443 tag_len - 4,
1444 secattr);
1445 if (ret_val != 0) {
Paul Moore16efd452008-01-29 08:37:59 -05001446 netlbl_secattr_catmap_free(secattr->attr.mls.cat);
Paul Moore654bbc22006-11-29 13:18:19 -05001447 return ret_val;
1448 }
1449
1450 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
1451 }
1452
1453 return 0;
1454}
1455
1456/**
Paul Moore484b3662006-11-29 13:18:20 -05001457 * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5)
1458 * @doi_def: the DOI definition
1459 * @secattr: the security attributes
1460 * @buffer: the option buffer
1461 * @buffer_len: length of buffer in bytes
1462 *
1463 * Description:
1464 * Generate a CIPSO option using the ranged tag, tag type #5. Returns the
1465 * size of the tag on success, negative values on failure.
1466 *
1467 */
1468static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def,
1469 const struct netlbl_lsm_secattr *secattr,
1470 unsigned char *buffer,
1471 u32 buffer_len)
1472{
1473 int ret_val;
1474 u32 tag_len;
1475 u32 level;
1476
1477 if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL))
1478 return -EPERM;
1479
Paul Moore16efd452008-01-29 08:37:59 -05001480 ret_val = cipso_v4_map_lvl_hton(doi_def,
1481 secattr->attr.mls.lvl,
1482 &level);
Paul Moore484b3662006-11-29 13:18:20 -05001483 if (ret_val != 0)
1484 return ret_val;
1485
1486 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
1487 ret_val = cipso_v4_map_cat_rng_hton(doi_def,
1488 secattr,
1489 &buffer[4],
1490 buffer_len - 4);
1491 if (ret_val < 0)
1492 return ret_val;
1493
1494 tag_len = 4 + ret_val;
1495 } else
1496 tag_len = 4;
1497
Paul Moore15c45f72008-10-10 10:16:34 -04001498 buffer[0] = CIPSO_V4_TAG_RANGE;
Paul Moore484b3662006-11-29 13:18:20 -05001499 buffer[1] = tag_len;
1500 buffer[3] = level;
1501
1502 return tag_len;
1503}
1504
1505/**
1506 * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag
1507 * @doi_def: the DOI definition
1508 * @tag: the CIPSO tag
1509 * @secattr: the security attributes
1510 *
1511 * Description:
1512 * Parse a CIPSO ranged tag (tag type #5) and return the security attributes
1513 * in @secattr. Return zero on success, negatives values on failure.
1514 *
1515 */
1516static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def,
1517 const unsigned char *tag,
1518 struct netlbl_lsm_secattr *secattr)
1519{
1520 int ret_val;
1521 u8 tag_len = tag[1];
1522 u32 level;
1523
1524 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1525 if (ret_val != 0)
1526 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001527 secattr->attr.mls.lvl = level;
Paul Moore484b3662006-11-29 13:18:20 -05001528 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
1529
1530 if (tag_len > 4) {
Paul Moore16efd452008-01-29 08:37:59 -05001531 secattr->attr.mls.cat =
1532 netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1533 if (secattr->attr.mls.cat == NULL)
Paul Moore484b3662006-11-29 13:18:20 -05001534 return -ENOMEM;
1535
1536 ret_val = cipso_v4_map_cat_rng_ntoh(doi_def,
1537 &tag[4],
1538 tag_len - 4,
1539 secattr);
1540 if (ret_val != 0) {
Paul Moore16efd452008-01-29 08:37:59 -05001541 netlbl_secattr_catmap_free(secattr->attr.mls.cat);
Paul Moore484b3662006-11-29 13:18:20 -05001542 return ret_val;
1543 }
1544
1545 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
1546 }
1547
1548 return 0;
1549}
1550
1551/**
Paul Moore15c45f72008-10-10 10:16:34 -04001552 * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard)
1553 * @doi_def: the DOI definition
1554 * @secattr: the security attributes
1555 * @buffer: the option buffer
1556 * @buffer_len: length of buffer in bytes
1557 *
1558 * Description:
1559 * Generate a CIPSO option using the local tag. Returns the size of the tag
1560 * on success, negative values on failure.
1561 *
1562 */
1563static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def,
1564 const struct netlbl_lsm_secattr *secattr,
1565 unsigned char *buffer,
1566 u32 buffer_len)
1567{
1568 if (!(secattr->flags & NETLBL_SECATTR_SECID))
1569 return -EPERM;
1570
1571 buffer[0] = CIPSO_V4_TAG_LOCAL;
1572 buffer[1] = CIPSO_V4_TAG_LOC_BLEN;
1573 *(u32 *)&buffer[2] = secattr->attr.secid;
1574
1575 return CIPSO_V4_TAG_LOC_BLEN;
1576}
1577
1578/**
1579 * cipso_v4_parsetag_loc - Parse a CIPSO local tag
1580 * @doi_def: the DOI definition
1581 * @tag: the CIPSO tag
1582 * @secattr: the security attributes
1583 *
1584 * Description:
1585 * Parse a CIPSO local tag and return the security attributes in @secattr.
1586 * Return zero on success, negatives values on failure.
1587 *
1588 */
1589static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def,
1590 const unsigned char *tag,
1591 struct netlbl_lsm_secattr *secattr)
1592{
1593 secattr->attr.secid = *(u32 *)&tag[2];
1594 secattr->flags |= NETLBL_SECATTR_SECID;
1595
1596 return 0;
1597}
1598
1599/**
Paul Moore446fda42006-08-03 16:48:06 -07001600 * cipso_v4_validate - Validate a CIPSO option
1601 * @option: the start of the option, on error it is set to point to the error
1602 *
1603 * Description:
1604 * This routine is called to validate a CIPSO option, it checks all of the
1605 * fields to ensure that they are at least valid, see the draft snippet below
1606 * for details. If the option is valid then a zero value is returned and
1607 * the value of @option is unchanged. If the option is invalid then a
1608 * non-zero value is returned and @option is adjusted to point to the
1609 * offending portion of the option. From the IETF draft ...
1610 *
1611 * "If any field within the CIPSO options, such as the DOI identifier, is not
1612 * recognized the IP datagram is discarded and an ICMP 'parameter problem'
1613 * (type 12) is generated and returned. The ICMP code field is set to 'bad
1614 * parameter' (code 0) and the pointer is set to the start of the CIPSO field
1615 * that is unrecognized."
1616 *
1617 */
Paul Moore15c45f72008-10-10 10:16:34 -04001618int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
Paul Moore446fda42006-08-03 16:48:06 -07001619{
1620 unsigned char *opt = *option;
1621 unsigned char *tag;
1622 unsigned char opt_iter;
1623 unsigned char err_offset = 0;
1624 u8 opt_len;
1625 u8 tag_len;
1626 struct cipso_v4_doi *doi_def = NULL;
1627 u32 tag_iter;
1628
1629 /* caller already checks for length values that are too large */
1630 opt_len = opt[1];
1631 if (opt_len < 8) {
1632 err_offset = 1;
1633 goto validate_return;
1634 }
1635
1636 rcu_read_lock();
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001637 doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2]));
Paul Moore446fda42006-08-03 16:48:06 -07001638 if (doi_def == NULL) {
1639 err_offset = 2;
1640 goto validate_return_locked;
1641 }
1642
Paul Moore15c45f72008-10-10 10:16:34 -04001643 opt_iter = CIPSO_V4_HDR_LEN;
Paul Moore446fda42006-08-03 16:48:06 -07001644 tag = opt + opt_iter;
1645 while (opt_iter < opt_len) {
1646 for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];)
1647 if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID ||
1648 ++tag_iter == CIPSO_V4_TAG_MAXCNT) {
1649 err_offset = opt_iter;
1650 goto validate_return_locked;
1651 }
1652
1653 tag_len = tag[1];
1654 if (tag_len > (opt_len - opt_iter)) {
1655 err_offset = opt_iter + 1;
1656 goto validate_return_locked;
1657 }
1658
1659 switch (tag[0]) {
1660 case CIPSO_V4_TAG_RBITMAP:
Paul Moore15c45f72008-10-10 10:16:34 -04001661 if (tag_len < CIPSO_V4_TAG_RBM_BLEN) {
Paul Moore446fda42006-08-03 16:48:06 -07001662 err_offset = opt_iter + 1;
1663 goto validate_return_locked;
1664 }
1665
1666 /* We are already going to do all the verification
1667 * necessary at the socket layer so from our point of
1668 * view it is safe to turn these checks off (and less
1669 * work), however, the CIPSO draft says we should do
1670 * all the CIPSO validations here but it doesn't
1671 * really specify _exactly_ what we need to validate
1672 * ... so, just make it a sysctl tunable. */
1673 if (cipso_v4_rbm_strictvalid) {
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_RBM_BLEN &&
Paul Moore446fda42006-08-03 16:48:06 -07001680 cipso_v4_map_cat_rbm_valid(doi_def,
1681 &tag[4],
1682 tag_len - 4) < 0) {
1683 err_offset = opt_iter + 4;
1684 goto validate_return_locked;
1685 }
1686 }
1687 break;
Paul Moore654bbc22006-11-29 13:18:19 -05001688 case CIPSO_V4_TAG_ENUM:
Paul Moore15c45f72008-10-10 10:16:34 -04001689 if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) {
Paul Moore654bbc22006-11-29 13:18:19 -05001690 err_offset = opt_iter + 1;
1691 goto validate_return_locked;
1692 }
1693
1694 if (cipso_v4_map_lvl_valid(doi_def,
1695 tag[3]) < 0) {
1696 err_offset = opt_iter + 3;
1697 goto validate_return_locked;
1698 }
Paul Moore15c45f72008-10-10 10:16:34 -04001699 if (tag_len > CIPSO_V4_TAG_ENUM_BLEN &&
Paul Moore654bbc22006-11-29 13:18:19 -05001700 cipso_v4_map_cat_enum_valid(doi_def,
1701 &tag[4],
1702 tag_len - 4) < 0) {
1703 err_offset = opt_iter + 4;
1704 goto validate_return_locked;
1705 }
1706 break;
Paul Moore484b3662006-11-29 13:18:20 -05001707 case CIPSO_V4_TAG_RANGE:
Paul Moore15c45f72008-10-10 10:16:34 -04001708 if (tag_len < CIPSO_V4_TAG_RNG_BLEN) {
Paul Moore484b3662006-11-29 13:18:20 -05001709 err_offset = opt_iter + 1;
1710 goto validate_return_locked;
1711 }
1712
1713 if (cipso_v4_map_lvl_valid(doi_def,
1714 tag[3]) < 0) {
1715 err_offset = opt_iter + 3;
1716 goto validate_return_locked;
1717 }
Paul Moore15c45f72008-10-10 10:16:34 -04001718 if (tag_len > CIPSO_V4_TAG_RNG_BLEN &&
Paul Moore484b3662006-11-29 13:18:20 -05001719 cipso_v4_map_cat_rng_valid(doi_def,
1720 &tag[4],
1721 tag_len - 4) < 0) {
1722 err_offset = opt_iter + 4;
1723 goto validate_return_locked;
1724 }
1725 break;
Paul Moore15c45f72008-10-10 10:16:34 -04001726 case CIPSO_V4_TAG_LOCAL:
1727 /* This is a non-standard tag that we only allow for
1728 * local connections, so if the incoming interface is
1729 * not the loopback device drop the packet. */
1730 if (!(skb->dev->flags & IFF_LOOPBACK)) {
1731 err_offset = opt_iter;
1732 goto validate_return_locked;
1733 }
1734 if (tag_len != CIPSO_V4_TAG_LOC_BLEN) {
1735 err_offset = opt_iter + 1;
1736 goto validate_return_locked;
1737 }
1738 break;
Paul Moore446fda42006-08-03 16:48:06 -07001739 default:
1740 err_offset = opt_iter;
1741 goto validate_return_locked;
1742 }
1743
1744 tag += tag_len;
1745 opt_iter += tag_len;
1746 }
1747
1748validate_return_locked:
1749 rcu_read_unlock();
1750validate_return:
1751 *option = opt + err_offset;
1752 return err_offset;
1753}
1754
1755/**
1756 * cipso_v4_error - Send the correct reponse for a bad packet
1757 * @skb: the packet
1758 * @error: the error code
1759 * @gateway: CIPSO gateway flag
1760 *
1761 * Description:
1762 * Based on the error code given in @error, send an ICMP error message back to
1763 * the originating host. From the IETF draft ...
1764 *
1765 * "If the contents of the CIPSO [option] are valid but the security label is
1766 * outside of the configured host or port label range, the datagram is
1767 * discarded and an ICMP 'destination unreachable' (type 3) is generated and
1768 * returned. The code field of the ICMP is set to 'communication with
1769 * destination network administratively prohibited' (code 9) or to
1770 * 'communication with destination host administratively prohibited'
1771 * (code 10). The value of the code is dependent on whether the originator
1772 * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The
1773 * recipient of the ICMP message MUST be able to handle either value. The
1774 * same procedure is performed if a CIPSO [option] can not be added to an
1775 * IP packet because it is too large to fit in the IP options area."
1776 *
1777 * "If the error is triggered by receipt of an ICMP message, the message is
1778 * discarded and no response is permitted (consistent with general ICMP
1779 * processing rules)."
1780 *
1781 */
1782void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway)
1783{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001784 if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES)
Paul Moore446fda42006-08-03 16:48:06 -07001785 return;
1786
1787 if (gateway)
1788 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0);
1789 else
1790 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0);
1791}
1792
1793/**
Paul Moore948bf852008-10-10 10:16:32 -04001794 * cipso_v4_genopt - Generate a CIPSO option
1795 * @buf: the option buffer
1796 * @buf_len: the size of opt_buf
Paul Moore446fda42006-08-03 16:48:06 -07001797 * @doi_def: the CIPSO DOI to use
Paul Moore948bf852008-10-10 10:16:32 -04001798 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -07001799 *
1800 * Description:
Paul Moore948bf852008-10-10 10:16:32 -04001801 * Generate a CIPSO option using the DOI definition and security attributes
1802 * passed to the function. Returns the length of the option on success and
1803 * negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -07001804 *
1805 */
Paul Moore948bf852008-10-10 10:16:32 -04001806static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
1807 const struct cipso_v4_doi *doi_def,
1808 const struct netlbl_lsm_secattr *secattr)
Paul Moore446fda42006-08-03 16:48:06 -07001809{
Paul Moore948bf852008-10-10 10:16:32 -04001810 int ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001811 u32 iter;
Paul Moore446fda42006-08-03 16:48:06 -07001812
Paul Moore948bf852008-10-10 10:16:32 -04001813 if (buf_len <= CIPSO_V4_HDR_LEN)
1814 return -ENOSPC;
Paul Moore91b1ed02006-11-17 17:38:49 -05001815
Paul Moore446fda42006-08-03 16:48:06 -07001816 /* XXX - This code assumes only one tag per CIPSO option which isn't
1817 * really a good assumption to make but since we only support the MAC
1818 * tags right now it is a safe assumption. */
1819 iter = 0;
1820 do {
Paul Moore91b1ed02006-11-17 17:38:49 -05001821 memset(buf, 0, buf_len);
Paul Moore446fda42006-08-03 16:48:06 -07001822 switch (doi_def->tags[iter]) {
1823 case CIPSO_V4_TAG_RBITMAP:
1824 ret_val = cipso_v4_gentag_rbm(doi_def,
Paul Moore91b1ed02006-11-17 17:38:49 -05001825 secattr,
1826 &buf[CIPSO_V4_HDR_LEN],
1827 buf_len - CIPSO_V4_HDR_LEN);
Paul Moore446fda42006-08-03 16:48:06 -07001828 break;
Paul Moore654bbc22006-11-29 13:18:19 -05001829 case CIPSO_V4_TAG_ENUM:
1830 ret_val = cipso_v4_gentag_enum(doi_def,
1831 secattr,
1832 &buf[CIPSO_V4_HDR_LEN],
1833 buf_len - CIPSO_V4_HDR_LEN);
1834 break;
Paul Moore484b3662006-11-29 13:18:20 -05001835 case CIPSO_V4_TAG_RANGE:
1836 ret_val = cipso_v4_gentag_rng(doi_def,
1837 secattr,
1838 &buf[CIPSO_V4_HDR_LEN],
1839 buf_len - CIPSO_V4_HDR_LEN);
1840 break;
Paul Moore15c45f72008-10-10 10:16:34 -04001841 case CIPSO_V4_TAG_LOCAL:
1842 ret_val = cipso_v4_gentag_loc(doi_def,
1843 secattr,
1844 &buf[CIPSO_V4_HDR_LEN],
1845 buf_len - CIPSO_V4_HDR_LEN);
1846 break;
Paul Moore446fda42006-08-03 16:48:06 -07001847 default:
Paul Moore948bf852008-10-10 10:16:32 -04001848 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -07001849 }
1850
1851 iter++;
Paul Moore91b1ed02006-11-17 17:38:49 -05001852 } while (ret_val < 0 &&
Paul Moore446fda42006-08-03 16:48:06 -07001853 iter < CIPSO_V4_TAG_MAXCNT &&
1854 doi_def->tags[iter] != CIPSO_V4_TAG_INVALID);
Paul Moore91b1ed02006-11-17 17:38:49 -05001855 if (ret_val < 0)
Paul Moore948bf852008-10-10 10:16:32 -04001856 return ret_val;
Paul Moore91b1ed02006-11-17 17:38:49 -05001857 cipso_v4_gentag_hdr(doi_def, buf, ret_val);
Paul Moore948bf852008-10-10 10:16:32 -04001858 return CIPSO_V4_HDR_LEN + ret_val;
1859}
1860
1861/**
1862 * cipso_v4_sock_setattr - Add a CIPSO option to a socket
1863 * @sk: the socket
1864 * @doi_def: the CIPSO DOI to use
1865 * @secattr: the specific security attributes of the socket
1866 *
1867 * Description:
1868 * Set the CIPSO option on the given socket using the DOI definition and
1869 * security attributes passed to the function. This function requires
1870 * exclusive access to @sk, which means it either needs to be in the
1871 * process of being created or locked. Returns zero on success and negative
1872 * values on failure.
1873 *
1874 */
1875int cipso_v4_sock_setattr(struct sock *sk,
1876 const struct cipso_v4_doi *doi_def,
1877 const struct netlbl_lsm_secattr *secattr)
1878{
1879 int ret_val = -EPERM;
1880 unsigned char *buf = NULL;
1881 u32 buf_len;
1882 u32 opt_len;
1883 struct ip_options *opt = NULL;
1884 struct inet_sock *sk_inet;
1885 struct inet_connection_sock *sk_conn;
1886
1887 /* In the case of sock_create_lite(), the sock->sk field is not
1888 * defined yet but it is not a problem as the only users of these
1889 * "lite" PF_INET sockets are functions which do an accept() call
1890 * afterwards so we will label the socket as part of the accept(). */
1891 if (sk == NULL)
1892 return 0;
1893
1894 /* We allocate the maximum CIPSO option size here so we are probably
1895 * being a little wasteful, but it makes our life _much_ easier later
1896 * on and after all we are only talking about 40 bytes. */
1897 buf_len = CIPSO_V4_OPT_LEN_MAX;
1898 buf = kmalloc(buf_len, GFP_ATOMIC);
1899 if (buf == NULL) {
1900 ret_val = -ENOMEM;
1901 goto socket_setattr_failure;
1902 }
1903
1904 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
1905 if (ret_val < 0)
1906 goto socket_setattr_failure;
1907 buf_len = ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001908
1909 /* We can't use ip_options_get() directly because it makes a call to
1910 * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
Paul Mooref8687af2006-10-30 15:22:15 -08001911 * we won't always have CAP_NET_RAW even though we _always_ want to
1912 * set the IPOPT_CIPSO option. */
Paul Moore446fda42006-08-03 16:48:06 -07001913 opt_len = (buf_len + 3) & ~3;
1914 opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
1915 if (opt == NULL) {
1916 ret_val = -ENOMEM;
1917 goto socket_setattr_failure;
1918 }
1919 memcpy(opt->__data, buf, buf_len);
1920 opt->optlen = opt_len;
Paul Mooref8687af2006-10-30 15:22:15 -08001921 opt->cipso = sizeof(struct iphdr);
Paul Moore446fda42006-08-03 16:48:06 -07001922 kfree(buf);
1923 buf = NULL;
Paul Moore446fda42006-08-03 16:48:06 -07001924
1925 sk_inet = inet_sk(sk);
1926 if (sk_inet->is_icsk) {
1927 sk_conn = inet_csk(sk);
1928 if (sk_inet->opt)
1929 sk_conn->icsk_ext_hdr_len -= sk_inet->opt->optlen;
1930 sk_conn->icsk_ext_hdr_len += opt->optlen;
1931 sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
1932 }
1933 opt = xchg(&sk_inet->opt, opt);
1934 kfree(opt);
1935
1936 return 0;
1937
1938socket_setattr_failure:
1939 kfree(buf);
1940 kfree(opt);
1941 return ret_val;
1942}
1943
1944/**
Paul Moore389fb8002009-03-27 17:10:34 -04001945 * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket
1946 * @req: the connection request socket
1947 * @doi_def: the CIPSO DOI to use
1948 * @secattr: the specific security attributes of the socket
Paul Moore014ab192008-10-10 10:16:33 -04001949 *
1950 * Description:
Paul Moore389fb8002009-03-27 17:10:34 -04001951 * Set the CIPSO option on the given socket using the DOI definition and
1952 * security attributes passed to the function. Returns zero on success and
1953 * negative values on failure.
Paul Moore014ab192008-10-10 10:16:33 -04001954 *
1955 */
Paul Moore389fb8002009-03-27 17:10:34 -04001956int cipso_v4_req_setattr(struct request_sock *req,
1957 const struct cipso_v4_doi *doi_def,
1958 const struct netlbl_lsm_secattr *secattr)
Paul Moore014ab192008-10-10 10:16:33 -04001959{
Paul Moore389fb8002009-03-27 17:10:34 -04001960 int ret_val = -EPERM;
1961 unsigned char *buf = NULL;
1962 u32 buf_len;
1963 u32 opt_len;
1964 struct ip_options *opt = NULL;
1965 struct inet_request_sock *req_inet;
Paul Moore014ab192008-10-10 10:16:33 -04001966
Paul Moore389fb8002009-03-27 17:10:34 -04001967 /* We allocate the maximum CIPSO option size here so we are probably
1968 * being a little wasteful, but it makes our life _much_ easier later
1969 * on and after all we are only talking about 40 bytes. */
1970 buf_len = CIPSO_V4_OPT_LEN_MAX;
1971 buf = kmalloc(buf_len, GFP_ATOMIC);
1972 if (buf == NULL) {
1973 ret_val = -ENOMEM;
1974 goto req_setattr_failure;
1975 }
1976
1977 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
1978 if (ret_val < 0)
1979 goto req_setattr_failure;
1980 buf_len = ret_val;
1981
1982 /* We can't use ip_options_get() directly because it makes a call to
1983 * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
1984 * we won't always have CAP_NET_RAW even though we _always_ want to
1985 * set the IPOPT_CIPSO option. */
1986 opt_len = (buf_len + 3) & ~3;
1987 opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
1988 if (opt == NULL) {
1989 ret_val = -ENOMEM;
1990 goto req_setattr_failure;
1991 }
1992 memcpy(opt->__data, buf, buf_len);
1993 opt->optlen = opt_len;
1994 opt->cipso = sizeof(struct iphdr);
1995 kfree(buf);
1996 buf = NULL;
1997
1998 req_inet = inet_rsk(req);
1999 opt = xchg(&req_inet->opt, opt);
2000 kfree(opt);
2001
2002 return 0;
2003
2004req_setattr_failure:
2005 kfree(buf);
2006 kfree(opt);
2007 return ret_val;
2008}
2009
2010/**
2011 * cipso_v4_delopt - Delete the CIPSO option from a set of IP options
2012 * @opt_ptr: IP option pointer
2013 *
2014 * Description:
2015 * Deletes the CIPSO IP option from a set of IP options and makes the necessary
2016 * adjustments to the IP option structure. Returns zero on success, negative
2017 * values on failure.
2018 *
2019 */
2020int cipso_v4_delopt(struct ip_options **opt_ptr)
2021{
2022 int hdr_delta = 0;
2023 struct ip_options *opt = *opt_ptr;
Paul Moore014ab192008-10-10 10:16:33 -04002024
2025 if (opt->srr || opt->rr || opt->ts || opt->router_alert) {
2026 u8 cipso_len;
2027 u8 cipso_off;
2028 unsigned char *cipso_ptr;
2029 int iter;
2030 int optlen_new;
2031
2032 cipso_off = opt->cipso - sizeof(struct iphdr);
2033 cipso_ptr = &opt->__data[cipso_off];
2034 cipso_len = cipso_ptr[1];
2035
2036 if (opt->srr > opt->cipso)
2037 opt->srr -= cipso_len;
2038 if (opt->rr > opt->cipso)
2039 opt->rr -= cipso_len;
2040 if (opt->ts > opt->cipso)
2041 opt->ts -= cipso_len;
2042 if (opt->router_alert > opt->cipso)
2043 opt->router_alert -= cipso_len;
2044 opt->cipso = 0;
2045
2046 memmove(cipso_ptr, cipso_ptr + cipso_len,
2047 opt->optlen - cipso_off - cipso_len);
2048
2049 /* determining the new total option length is tricky because of
2050 * the padding necessary, the only thing i can think to do at
2051 * this point is walk the options one-by-one, skipping the
2052 * padding at the end to determine the actual option size and
2053 * from there we can determine the new total option length */
2054 iter = 0;
2055 optlen_new = 0;
2056 while (iter < opt->optlen)
2057 if (opt->__data[iter] != IPOPT_NOP) {
2058 iter += opt->__data[iter + 1];
2059 optlen_new = iter;
2060 } else
2061 iter++;
2062 hdr_delta = opt->optlen;
2063 opt->optlen = (optlen_new + 3) & ~3;
2064 hdr_delta -= opt->optlen;
2065 } else {
2066 /* only the cipso option was present on the socket so we can
2067 * remove the entire option struct */
Paul Moore389fb8002009-03-27 17:10:34 -04002068 *opt_ptr = NULL;
Paul Moore014ab192008-10-10 10:16:33 -04002069 hdr_delta = opt->optlen;
2070 kfree(opt);
2071 }
2072
Paul Moore389fb8002009-03-27 17:10:34 -04002073 return hdr_delta;
2074}
2075
2076/**
2077 * cipso_v4_sock_delattr - Delete the CIPSO option from a socket
2078 * @sk: the socket
2079 *
2080 * Description:
2081 * Removes the CIPSO option from a socket, if present.
2082 *
2083 */
2084void cipso_v4_sock_delattr(struct sock *sk)
2085{
2086 int hdr_delta;
2087 struct ip_options *opt;
2088 struct inet_sock *sk_inet;
2089
2090 sk_inet = inet_sk(sk);
2091 opt = sk_inet->opt;
2092 if (opt == NULL || opt->cipso == 0)
2093 return;
2094
2095 hdr_delta = cipso_v4_delopt(&sk_inet->opt);
Paul Moore014ab192008-10-10 10:16:33 -04002096 if (sk_inet->is_icsk && hdr_delta > 0) {
2097 struct inet_connection_sock *sk_conn = inet_csk(sk);
2098 sk_conn->icsk_ext_hdr_len -= hdr_delta;
2099 sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
2100 }
2101}
2102
2103/**
Paul Moore389fb8002009-03-27 17:10:34 -04002104 * cipso_v4_req_delattr - Delete the CIPSO option from a request socket
2105 * @reg: the request socket
2106 *
2107 * Description:
2108 * Removes the CIPSO option from a request socket, if present.
2109 *
2110 */
2111void cipso_v4_req_delattr(struct request_sock *req)
2112{
2113 struct ip_options *opt;
2114 struct inet_request_sock *req_inet;
2115
2116 req_inet = inet_rsk(req);
2117 opt = req_inet->opt;
2118 if (opt == NULL || opt->cipso == 0)
2119 return;
2120
2121 cipso_v4_delopt(&req_inet->opt);
2122}
2123
2124/**
Paul Moore63d804ea2007-09-15 21:45:13 -07002125 * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions
2126 * @cipso: the CIPSO v4 option
2127 * @secattr: the security attributes
2128 *
2129 * Description:
2130 * Inspect @cipso and return the security attributes in @secattr. Returns zero
2131 * on success and negative values on failure.
2132 *
2133 */
2134static int cipso_v4_getattr(const unsigned char *cipso,
2135 struct netlbl_lsm_secattr *secattr)
2136{
2137 int ret_val = -ENOMSG;
2138 u32 doi;
2139 struct cipso_v4_doi *doi_def;
2140
2141 if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0)
2142 return 0;
2143
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07002144 doi = get_unaligned_be32(&cipso[2]);
Paul Moore63d804ea2007-09-15 21:45:13 -07002145 rcu_read_lock();
2146 doi_def = cipso_v4_doi_search(doi);
2147 if (doi_def == NULL)
2148 goto getattr_return;
2149 /* XXX - This code assumes only one tag per CIPSO option which isn't
2150 * really a good assumption to make but since we only support the MAC
2151 * tags right now it is a safe assumption. */
2152 switch (cipso[6]) {
2153 case CIPSO_V4_TAG_RBITMAP:
2154 ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr);
2155 break;
2156 case CIPSO_V4_TAG_ENUM:
2157 ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr);
2158 break;
2159 case CIPSO_V4_TAG_RANGE:
2160 ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr);
2161 break;
Paul Moore15c45f72008-10-10 10:16:34 -04002162 case CIPSO_V4_TAG_LOCAL:
2163 ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr);
2164 break;
Paul Moore63d804ea2007-09-15 21:45:13 -07002165 }
Paul Moore16efd452008-01-29 08:37:59 -05002166 if (ret_val == 0)
2167 secattr->type = NETLBL_NLTYPE_CIPSOV4;
Paul Moore63d804ea2007-09-15 21:45:13 -07002168
2169getattr_return:
2170 rcu_read_unlock();
2171 return ret_val;
2172}
2173
2174/**
Paul Moore14a72f52006-09-25 15:52:01 -07002175 * cipso_v4_sock_getattr - Get the security attributes from a sock
2176 * @sk: the sock
2177 * @secattr: the security attributes
2178 *
2179 * Description:
2180 * Query @sk to see if there is a CIPSO option attached to the sock and if
2181 * there is return the CIPSO security attributes in @secattr. This function
2182 * requires that @sk be locked, or privately held, but it does not do any
2183 * locking itself. Returns zero on success and negative values on failure.
2184 *
2185 */
2186int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
2187{
Paul Moore63d804ea2007-09-15 21:45:13 -07002188 struct ip_options *opt;
Paul Moore14a72f52006-09-25 15:52:01 -07002189
Paul Moore63d804ea2007-09-15 21:45:13 -07002190 opt = inet_sk(sk)->opt;
2191 if (opt == NULL || opt->cipso == 0)
Paul Moore14a72f52006-09-25 15:52:01 -07002192 return -ENOMSG;
Paul Moore14a72f52006-09-25 15:52:01 -07002193
Paul Moore63d804ea2007-09-15 21:45:13 -07002194 return cipso_v4_getattr(opt->__data + opt->cipso - sizeof(struct iphdr),
2195 secattr);
Paul Moore14a72f52006-09-25 15:52:01 -07002196}
2197
2198/**
Paul Moore948bf852008-10-10 10:16:32 -04002199 * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet
2200 * @skb: the packet
2201 * @secattr: the security attributes
2202 *
2203 * Description:
2204 * Set the CIPSO option on the given packet based on the security attributes.
2205 * Returns a pointer to the IP header on success and NULL on failure.
2206 *
2207 */
2208int cipso_v4_skbuff_setattr(struct sk_buff *skb,
2209 const struct cipso_v4_doi *doi_def,
2210 const struct netlbl_lsm_secattr *secattr)
2211{
2212 int ret_val;
2213 struct iphdr *iph;
2214 struct ip_options *opt = &IPCB(skb)->opt;
2215 unsigned char buf[CIPSO_V4_OPT_LEN_MAX];
2216 u32 buf_len = CIPSO_V4_OPT_LEN_MAX;
2217 u32 opt_len;
2218 int len_delta;
2219
roel kluin00af5c62008-10-29 15:55:53 -04002220 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
2221 if (ret_val < 0)
2222 return ret_val;
2223 buf_len = ret_val;
Paul Moore948bf852008-10-10 10:16:32 -04002224 opt_len = (buf_len + 3) & ~3;
2225
2226 /* we overwrite any existing options to ensure that we have enough
2227 * room for the CIPSO option, the reason is that we _need_ to guarantee
2228 * that the security label is applied to the packet - we do the same
2229 * thing when using the socket options and it hasn't caused a problem,
2230 * if we need to we can always revisit this choice later */
2231
2232 len_delta = opt_len - opt->optlen;
2233 /* if we don't ensure enough headroom we could panic on the skb_push()
2234 * call below so make sure we have enough, we are also "mangling" the
2235 * packet so we should probably do a copy-on-write call anyway */
2236 ret_val = skb_cow(skb, skb_headroom(skb) + len_delta);
2237 if (ret_val < 0)
2238 return ret_val;
2239
2240 if (len_delta > 0) {
2241 /* we assume that the header + opt->optlen have already been
2242 * "pushed" in ip_options_build() or similar */
2243 iph = ip_hdr(skb);
2244 skb_push(skb, len_delta);
2245 memmove((char *)iph - len_delta, iph, iph->ihl << 2);
2246 skb_reset_network_header(skb);
2247 iph = ip_hdr(skb);
2248 } else if (len_delta < 0) {
2249 iph = ip_hdr(skb);
2250 memset(iph + 1, IPOPT_NOP, opt->optlen);
2251 } else
2252 iph = ip_hdr(skb);
2253
2254 if (opt->optlen > 0)
2255 memset(opt, 0, sizeof(*opt));
2256 opt->optlen = opt_len;
2257 opt->cipso = sizeof(struct iphdr);
2258 opt->is_changed = 1;
2259
2260 /* we have to do the following because we are being called from a
2261 * netfilter hook which means the packet already has had the header
2262 * fields populated and the checksum calculated - yes this means we
2263 * are doing more work than needed but we do it to keep the core
2264 * stack clean and tidy */
2265 memcpy(iph + 1, buf, buf_len);
2266 if (opt_len > buf_len)
2267 memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len);
2268 if (len_delta != 0) {
2269 iph->ihl = 5 + (opt_len >> 2);
2270 iph->tot_len = htons(skb->len);
2271 }
2272 ip_send_check(iph);
2273
2274 return 0;
2275}
2276
2277/**
2278 * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet
2279 * @skb: the packet
2280 *
2281 * Description:
2282 * Removes any and all CIPSO options from the given packet. Returns zero on
2283 * success, negative values on failure.
2284 *
2285 */
2286int cipso_v4_skbuff_delattr(struct sk_buff *skb)
2287{
2288 int ret_val;
2289 struct iphdr *iph;
2290 struct ip_options *opt = &IPCB(skb)->opt;
2291 unsigned char *cipso_ptr;
2292
2293 if (opt->cipso == 0)
2294 return 0;
2295
2296 /* since we are changing the packet we should make a copy */
2297 ret_val = skb_cow(skb, skb_headroom(skb));
2298 if (ret_val < 0)
2299 return ret_val;
2300
2301 /* the easiest thing to do is just replace the cipso option with noop
2302 * options since we don't change the size of the packet, although we
2303 * still need to recalculate the checksum */
2304
2305 iph = ip_hdr(skb);
2306 cipso_ptr = (unsigned char *)iph + opt->cipso;
2307 memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]);
2308 opt->cipso = 0;
2309 opt->is_changed = 1;
2310
2311 ip_send_check(iph);
2312
2313 return 0;
2314}
2315
2316/**
Paul Moore446fda42006-08-03 16:48:06 -07002317 * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option
2318 * @skb: the packet
2319 * @secattr: the security attributes
2320 *
2321 * Description:
2322 * Parse the given packet's CIPSO option and return the security attributes.
2323 * Returns zero on success and negative values on failure.
2324 *
2325 */
2326int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
2327 struct netlbl_lsm_secattr *secattr)
2328{
Paul Moore63d804ea2007-09-15 21:45:13 -07002329 return cipso_v4_getattr(CIPSO_V4_OPTPTR(skb), secattr);
Paul Moore446fda42006-08-03 16:48:06 -07002330}
2331
2332/*
2333 * Setup Functions
2334 */
2335
2336/**
2337 * cipso_v4_init - Initialize the CIPSO module
2338 *
2339 * Description:
2340 * Initialize the CIPSO module and prepare it for use. Returns zero on success
2341 * and negative values on failure.
2342 *
2343 */
2344static int __init cipso_v4_init(void)
2345{
2346 int ret_val;
2347
2348 ret_val = cipso_v4_cache_init();
2349 if (ret_val != 0)
2350 panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n",
2351 ret_val);
2352
2353 return 0;
2354}
2355
2356subsys_initcall(cipso_v4_init);