blob: 2b3c23c287cdf343670195846f68b84f6ce02d4a [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
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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090047#include <linux/slab.h>
Paul Moore446fda42006-08-03 16:48:06 -070048#include <net/ip.h>
49#include <net/icmp.h>
50#include <net/tcp.h>
51#include <net/netlabel.h>
52#include <net/cipso_ipv4.h>
paul.moore@hp.comffb733c2006-10-04 11:46:31 -040053#include <asm/atomic.h>
Paul Moore446fda42006-08-03 16:48:06 -070054#include <asm/bug.h>
Paul Moore50e5d352007-06-07 18:38:14 -070055#include <asm/unaligned.h>
Paul Moore446fda42006-08-03 16:48:06 -070056
Paul Moore446fda42006-08-03 16:48:06 -070057/* List of available DOI definitions */
Paul Moore446fda42006-08-03 16:48:06 -070058/* XXX - This currently assumes a minimal number of different DOIs in use,
59 * if in practice there are a lot of different DOIs this list should
60 * probably be turned into a hash table or something similar so we
61 * can do quick lookups. */
Adrian Bunk8ce11e62006-08-07 21:50:48 -070062static DEFINE_SPINLOCK(cipso_v4_doi_list_lock);
Denis Cheng1596c972007-12-07 00:49:47 -080063static LIST_HEAD(cipso_v4_doi_list);
Paul Moore446fda42006-08-03 16:48:06 -070064
65/* Label mapping cache */
66int cipso_v4_cache_enabled = 1;
67int cipso_v4_cache_bucketsize = 10;
68#define CIPSO_V4_CACHE_BUCKETBITS 7
69#define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS)
70#define CIPSO_V4_CACHE_REORDERLIMIT 10
71struct cipso_v4_map_cache_bkt {
72 spinlock_t lock;
73 u32 size;
74 struct list_head list;
75};
76struct cipso_v4_map_cache_entry {
77 u32 hash;
78 unsigned char *key;
79 size_t key_len;
80
paul.moore@hp.comffb733c2006-10-04 11:46:31 -040081 struct netlbl_lsm_cache *lsm_data;
Paul Moore446fda42006-08-03 16:48:06 -070082
83 u32 activity;
84 struct list_head list;
85};
86static struct cipso_v4_map_cache_bkt *cipso_v4_cache = NULL;
87
88/* Restricted bitmap (tag #1) flags */
89int cipso_v4_rbm_optfmt = 0;
90int cipso_v4_rbm_strictvalid = 1;
91
92/*
Paul Mooref998e8c2007-02-28 15:14:20 -050093 * Protocol Constants
94 */
95
96/* Maximum size of the CIPSO IP option, derived from the fact that the maximum
97 * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */
98#define CIPSO_V4_OPT_LEN_MAX 40
99
100/* Length of the base CIPSO option, this includes the option type (1 byte), the
101 * option length (1 byte), and the DOI (4 bytes). */
102#define CIPSO_V4_HDR_LEN 6
103
104/* Base length of the restrictive category bitmap tag (tag #1). */
105#define CIPSO_V4_TAG_RBM_BLEN 4
106
107/* Base length of the enumerated category tag (tag #2). */
108#define CIPSO_V4_TAG_ENUM_BLEN 4
109
110/* Base length of the ranged categories bitmap tag (tag #5). */
111#define CIPSO_V4_TAG_RNG_BLEN 4
112/* The maximum number of category ranges permitted in the ranged category tag
113 * (tag #5). You may note that the IETF draft states that the maximum number
114 * of category ranges is 7, but if the low end of the last category range is
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300115 * zero then it is possible to fit 8 category ranges because the zero should
Paul Mooref998e8c2007-02-28 15:14:20 -0500116 * be omitted. */
117#define CIPSO_V4_TAG_RNG_CAT_MAX 8
118
Paul Moore15c45f72008-10-10 10:16:34 -0400119/* Base length of the local tag (non-standard tag).
120 * Tag definition (may change between kernel versions)
121 *
122 * 0 8 16 24 32
123 * +----------+----------+----------+----------+
124 * | 10000000 | 00000110 | 32-bit secid value |
125 * +----------+----------+----------+----------+
126 * | in (host byte order)|
127 * +----------+----------+
128 *
129 */
130#define CIPSO_V4_TAG_LOC_BLEN 6
131
Paul Mooref998e8c2007-02-28 15:14:20 -0500132/*
Paul Moore446fda42006-08-03 16:48:06 -0700133 * Helper Functions
134 */
135
136/**
137 * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit
138 * @bitmap: the bitmap
139 * @bitmap_len: length in bits
140 * @offset: starting offset
141 * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit
142 *
143 * Description:
144 * Starting at @offset, walk the bitmap from left to right until either the
145 * desired bit is found or we reach the end. Return the bit offset, -1 if
146 * not found, or -2 if error.
147 */
148static int cipso_v4_bitmap_walk(const unsigned char *bitmap,
149 u32 bitmap_len,
150 u32 offset,
151 u8 state)
152{
153 u32 bit_spot;
154 u32 byte_offset;
155 unsigned char bitmask;
156 unsigned char byte;
157
158 /* gcc always rounds to zero when doing integer division */
159 byte_offset = offset / 8;
160 byte = bitmap[byte_offset];
161 bit_spot = offset;
162 bitmask = 0x80 >> (offset % 8);
163
164 while (bit_spot < bitmap_len) {
165 if ((state && (byte & bitmask) == bitmask) ||
166 (state == 0 && (byte & bitmask) == 0))
167 return bit_spot;
168
169 bit_spot++;
170 bitmask >>= 1;
171 if (bitmask == 0) {
172 byte = bitmap[++byte_offset];
173 bitmask = 0x80;
174 }
175 }
176
177 return -1;
178}
179
180/**
181 * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap
182 * @bitmap: the bitmap
183 * @bit: the bit
184 * @state: if non-zero, set the bit (1) else clear the bit (0)
185 *
186 * Description:
187 * Set a single bit in the bitmask. Returns zero on success, negative values
188 * on error.
189 */
190static void cipso_v4_bitmap_setbit(unsigned char *bitmap,
191 u32 bit,
192 u8 state)
193{
194 u32 byte_spot;
195 u8 bitmask;
196
197 /* gcc always rounds to zero when doing integer division */
198 byte_spot = bit / 8;
199 bitmask = 0x80 >> (bit % 8);
200 if (state)
201 bitmap[byte_spot] |= bitmask;
202 else
203 bitmap[byte_spot] &= ~bitmask;
204}
205
206/**
Paul Moore446fda42006-08-03 16:48:06 -0700207 * cipso_v4_cache_entry_free - Frees a cache entry
208 * @entry: the entry to free
209 *
210 * Description:
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400211 * This function frees the memory associated with a cache entry including the
212 * LSM cache data if there are no longer any users, i.e. reference count == 0.
Paul Moore446fda42006-08-03 16:48:06 -0700213 *
214 */
215static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry)
216{
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400217 if (entry->lsm_data)
218 netlbl_secattr_cache_free(entry->lsm_data);
Paul Moore446fda42006-08-03 16:48:06 -0700219 kfree(entry->key);
220 kfree(entry);
221}
222
223/**
224 * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache
225 * @key: the hash key
226 * @key_len: the length of the key in bytes
227 *
228 * Description:
229 * The CIPSO tag hashing function. Returns a 32-bit hash value.
230 *
231 */
232static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len)
233{
234 return jhash(key, key_len, 0);
235}
236
237/*
238 * Label Mapping Cache Functions
239 */
240
241/**
242 * cipso_v4_cache_init - Initialize the CIPSO cache
243 *
244 * Description:
245 * Initializes the CIPSO label mapping cache, this function should be called
246 * before any of the other functions defined in this file. Returns zero on
247 * success, negative values on error.
248 *
249 */
250static int cipso_v4_cache_init(void)
251{
252 u32 iter;
253
254 cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS,
255 sizeof(struct cipso_v4_map_cache_bkt),
256 GFP_KERNEL);
257 if (cipso_v4_cache == NULL)
258 return -ENOMEM;
259
260 for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) {
261 spin_lock_init(&cipso_v4_cache[iter].lock);
262 cipso_v4_cache[iter].size = 0;
263 INIT_LIST_HEAD(&cipso_v4_cache[iter].list);
264 }
265
266 return 0;
267}
268
269/**
270 * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache
271 *
272 * Description:
273 * Invalidates and frees any entries in the CIPSO cache. Returns zero on
274 * success and negative values on failure.
275 *
276 */
277void cipso_v4_cache_invalidate(void)
278{
279 struct cipso_v4_map_cache_entry *entry, *tmp_entry;
280 u32 iter;
281
282 for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) {
Paul Moore609c92f2006-09-25 15:52:37 -0700283 spin_lock_bh(&cipso_v4_cache[iter].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700284 list_for_each_entry_safe(entry,
285 tmp_entry,
286 &cipso_v4_cache[iter].list, list) {
287 list_del(&entry->list);
288 cipso_v4_cache_entry_free(entry);
289 }
290 cipso_v4_cache[iter].size = 0;
Paul Moore609c92f2006-09-25 15:52:37 -0700291 spin_unlock_bh(&cipso_v4_cache[iter].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700292 }
Paul Moore446fda42006-08-03 16:48:06 -0700293}
294
295/**
296 * cipso_v4_cache_check - Check the CIPSO cache for a label mapping
297 * @key: the buffer to check
298 * @key_len: buffer length in bytes
299 * @secattr: the security attribute struct to use
300 *
301 * Description:
302 * This function checks the cache to see if a label mapping already exists for
303 * the given key. If there is a match then the cache is adjusted and the
304 * @secattr struct is populated with the correct LSM security attributes. The
305 * cache is adjusted in the following manner if the entry is not already the
306 * first in the cache bucket:
307 *
308 * 1. The cache entry's activity counter is incremented
309 * 2. The previous (higher ranking) entry's activity counter is decremented
310 * 3. If the difference between the two activity counters is geater than
311 * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped
312 *
313 * Returns zero on success, -ENOENT for a cache miss, and other negative values
314 * on error.
315 *
316 */
317static int cipso_v4_cache_check(const unsigned char *key,
318 u32 key_len,
319 struct netlbl_lsm_secattr *secattr)
320{
321 u32 bkt;
322 struct cipso_v4_map_cache_entry *entry;
323 struct cipso_v4_map_cache_entry *prev_entry = NULL;
324 u32 hash;
325
326 if (!cipso_v4_cache_enabled)
327 return -ENOENT;
328
329 hash = cipso_v4_map_cache_hash(key, key_len);
Pavel Emelyanov5e0f8922008-05-13 23:23:55 -0700330 bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1);
Paul Moore609c92f2006-09-25 15:52:37 -0700331 spin_lock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700332 list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) {
333 if (entry->hash == hash &&
334 entry->key_len == key_len &&
335 memcmp(entry->key, key, key_len) == 0) {
336 entry->activity += 1;
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400337 atomic_inc(&entry->lsm_data->refcount);
338 secattr->cache = entry->lsm_data;
Paul Moore701a90b2006-11-17 17:38:46 -0500339 secattr->flags |= NETLBL_SECATTR_CACHE;
Paul Moore16efd452008-01-29 08:37:59 -0500340 secattr->type = NETLBL_NLTYPE_CIPSOV4;
Paul Moore446fda42006-08-03 16:48:06 -0700341 if (prev_entry == NULL) {
Paul Moore609c92f2006-09-25 15:52:37 -0700342 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700343 return 0;
344 }
345
346 if (prev_entry->activity > 0)
347 prev_entry->activity -= 1;
348 if (entry->activity > prev_entry->activity &&
349 entry->activity - prev_entry->activity >
350 CIPSO_V4_CACHE_REORDERLIMIT) {
351 __list_del(entry->list.prev, entry->list.next);
352 __list_add(&entry->list,
353 prev_entry->list.prev,
354 &prev_entry->list);
355 }
356
Paul Moore609c92f2006-09-25 15:52:37 -0700357 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700358 return 0;
359 }
360 prev_entry = entry;
361 }
Paul Moore609c92f2006-09-25 15:52:37 -0700362 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700363
364 return -ENOENT;
365}
366
367/**
368 * cipso_v4_cache_add - Add an entry to the CIPSO cache
369 * @skb: the packet
370 * @secattr: the packet's security attributes
371 *
372 * Description:
373 * Add a new entry into the CIPSO label mapping cache. Add the new entry to
374 * head of the cache bucket's list, if the cache bucket is out of room remove
375 * the last entry in the list first. It is important to note that there is
376 * currently no checking for duplicate keys. Returns zero on success,
377 * negative values on failure.
378 *
379 */
380int cipso_v4_cache_add(const struct sk_buff *skb,
381 const struct netlbl_lsm_secattr *secattr)
382{
383 int ret_val = -EPERM;
384 u32 bkt;
385 struct cipso_v4_map_cache_entry *entry = NULL;
386 struct cipso_v4_map_cache_entry *old_entry = NULL;
387 unsigned char *cipso_ptr;
388 u32 cipso_ptr_len;
389
390 if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0)
391 return 0;
392
393 cipso_ptr = CIPSO_V4_OPTPTR(skb);
394 cipso_ptr_len = cipso_ptr[1];
395
396 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
397 if (entry == NULL)
398 return -ENOMEM;
Arnaldo Carvalho de Melofac5d732006-11-17 11:14:16 -0200399 entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC);
Paul Moore446fda42006-08-03 16:48:06 -0700400 if (entry->key == NULL) {
401 ret_val = -ENOMEM;
402 goto cache_add_failure;
403 }
Paul Moore446fda42006-08-03 16:48:06 -0700404 entry->key_len = cipso_ptr_len;
405 entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len);
paul.moore@hp.comffb733c2006-10-04 11:46:31 -0400406 atomic_inc(&secattr->cache->refcount);
407 entry->lsm_data = secattr->cache;
Paul Moore446fda42006-08-03 16:48:06 -0700408
Pavel Emelyanov5e0f8922008-05-13 23:23:55 -0700409 bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1);
Paul Moore609c92f2006-09-25 15:52:37 -0700410 spin_lock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700411 if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
412 list_add(&entry->list, &cipso_v4_cache[bkt].list);
413 cipso_v4_cache[bkt].size += 1;
414 } else {
415 old_entry = list_entry(cipso_v4_cache[bkt].list.prev,
416 struct cipso_v4_map_cache_entry, list);
417 list_del(&old_entry->list);
418 list_add(&entry->list, &cipso_v4_cache[bkt].list);
419 cipso_v4_cache_entry_free(old_entry);
420 }
Paul Moore609c92f2006-09-25 15:52:37 -0700421 spin_unlock_bh(&cipso_v4_cache[bkt].lock);
Paul Moore446fda42006-08-03 16:48:06 -0700422
423 return 0;
424
425cache_add_failure:
426 if (entry)
427 cipso_v4_cache_entry_free(entry);
428 return ret_val;
429}
430
431/*
432 * DOI List Functions
433 */
434
435/**
436 * cipso_v4_doi_search - Searches for a DOI definition
437 * @doi: the DOI to search for
438 *
439 * Description:
440 * Search the DOI definition list for a DOI definition with a DOI value that
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300441 * matches @doi. The caller is responsible for calling rcu_read_[un]lock().
Paul Moore446fda42006-08-03 16:48:06 -0700442 * Returns a pointer to the DOI definition on success and NULL on failure.
443 */
444static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
445{
446 struct cipso_v4_doi *iter;
447
448 list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
Paul Mooreb1edeb12008-10-10 10:16:31 -0400449 if (iter->doi == doi && atomic_read(&iter->refcount))
Paul Moore446fda42006-08-03 16:48:06 -0700450 return iter;
451 return NULL;
452}
453
454/**
455 * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine
456 * @doi_def: the DOI structure
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500457 * @audit_info: NetLabel audit information
Paul Moore446fda42006-08-03 16:48:06 -0700458 *
459 * Description:
460 * The caller defines a new DOI for use by the CIPSO engine and calls this
461 * function to add it to the list of acceptable domains. The caller must
462 * ensure that the mapping table specified in @doi_def->map meets all of the
463 * requirements of the mapping type (see cipso_ipv4.h for details). Returns
464 * zero on success and non-zero on failure.
465 *
466 */
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500467int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
468 struct netlbl_audit *audit_info)
Paul Moore446fda42006-08-03 16:48:06 -0700469{
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500470 int ret_val = -EINVAL;
Paul Moore6ce61a72006-11-17 17:38:48 -0500471 u32 iter;
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500472 u32 doi;
473 u32 doi_type;
474 struct audit_buffer *audit_buf;
475
476 doi = doi_def->doi;
477 doi_type = doi_def->type;
Paul Moore6ce61a72006-11-17 17:38:48 -0500478
Paul Moore446fda42006-08-03 16:48:06 -0700479 if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500480 goto doi_add_return;
Paul Moore6ce61a72006-11-17 17:38:48 -0500481 for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) {
482 switch (doi_def->tags[iter]) {
483 case CIPSO_V4_TAG_RBITMAP:
484 break;
Paul Moore484b3662006-11-29 13:18:20 -0500485 case CIPSO_V4_TAG_RANGE:
Paul Moore654bbc22006-11-29 13:18:19 -0500486 case CIPSO_V4_TAG_ENUM:
487 if (doi_def->type != CIPSO_V4_MAP_PASS)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500488 goto doi_add_return;
Paul Moore654bbc22006-11-29 13:18:19 -0500489 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400490 case CIPSO_V4_TAG_LOCAL:
491 if (doi_def->type != CIPSO_V4_MAP_LOCAL)
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500492 goto doi_add_return;
493 break;
494 case CIPSO_V4_TAG_INVALID:
495 if (iter == 0)
496 goto doi_add_return;
Paul Moore15c45f72008-10-10 10:16:34 -0400497 break;
Paul Moore6ce61a72006-11-17 17:38:48 -0500498 default:
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500499 goto doi_add_return;
Paul Moore6ce61a72006-11-17 17:38:48 -0500500 }
501 }
Paul Moore446fda42006-08-03 16:48:06 -0700502
Paul Mooreb1edeb12008-10-10 10:16:31 -0400503 atomic_set(&doi_def->refcount, 1);
Paul Moore446fda42006-08-03 16:48:06 -0700504
Paul Moore446fda42006-08-03 16:48:06 -0700505 spin_lock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500506 if (cipso_v4_doi_search(doi_def->doi) != NULL) {
507 spin_unlock(&cipso_v4_doi_list_lock);
508 ret_val = -EEXIST;
509 goto doi_add_return;
510 }
Paul Moore446fda42006-08-03 16:48:06 -0700511 list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list);
512 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500513 ret_val = 0;
Paul Moore446fda42006-08-03 16:48:06 -0700514
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500515doi_add_return:
516 audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info);
517 if (audit_buf != NULL) {
518 const char *type_str;
519 switch (doi_type) {
520 case CIPSO_V4_MAP_TRANS:
521 type_str = "trans";
522 break;
523 case CIPSO_V4_MAP_PASS:
524 type_str = "pass";
525 break;
526 case CIPSO_V4_MAP_LOCAL:
527 type_str = "local";
528 break;
529 default:
530 type_str = "(unknown)";
531 }
532 audit_log_format(audit_buf,
533 " cipso_doi=%u cipso_type=%s res=%u",
534 doi, type_str, ret_val == 0 ? 1 : 0);
535 audit_log_end(audit_buf);
536 }
Paul Moore446fda42006-08-03 16:48:06 -0700537
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500538 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700539}
540
541/**
Paul Mooreb1edeb12008-10-10 10:16:31 -0400542 * cipso_v4_doi_free - Frees a DOI definition
543 * @entry: the entry's RCU field
Paul Moore446fda42006-08-03 16:48:06 -0700544 *
545 * Description:
Paul Mooreb1edeb12008-10-10 10:16:31 -0400546 * This function frees all of the memory associated with a DOI definition.
Paul Moore446fda42006-08-03 16:48:06 -0700547 *
548 */
Paul Mooreb1edeb12008-10-10 10:16:31 -0400549void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
Paul Moore446fda42006-08-03 16:48:06 -0700550{
Paul Mooreb1edeb12008-10-10 10:16:31 -0400551 if (doi_def == NULL)
552 return;
Paul Moore446fda42006-08-03 16:48:06 -0700553
Paul Mooreb1edeb12008-10-10 10:16:31 -0400554 switch (doi_def->type) {
Paul Moore15c45f72008-10-10 10:16:34 -0400555 case CIPSO_V4_MAP_TRANS:
Paul Mooreb1edeb12008-10-10 10:16:31 -0400556 kfree(doi_def->map.std->lvl.cipso);
557 kfree(doi_def->map.std->lvl.local);
558 kfree(doi_def->map.std->cat.cipso);
559 kfree(doi_def->map.std->cat.local);
560 break;
Paul Moore446fda42006-08-03 16:48:06 -0700561 }
Paul Mooreb1edeb12008-10-10 10:16:31 -0400562 kfree(doi_def);
Paul Moore446fda42006-08-03 16:48:06 -0700563}
564
565/**
Paul Mooreb1edeb12008-10-10 10:16:31 -0400566 * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer
567 * @entry: the entry's RCU field
568 *
569 * Description:
570 * This function is designed to be used as a callback to the call_rcu()
571 * function so that the memory allocated to the DOI definition can be released
572 * safely.
573 *
574 */
575static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
576{
577 struct cipso_v4_doi *doi_def;
578
579 doi_def = container_of(entry, struct cipso_v4_doi, rcu);
580 cipso_v4_doi_free(doi_def);
581}
582
583/**
584 * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
585 * @doi: the DOI value
586 * @audit_secid: the LSM secid to use in the audit message
587 *
588 * Description:
589 * Removes a DOI definition from the CIPSO engine. The NetLabel routines will
590 * be called to release their own LSM domain mappings as well as our own
591 * domain list. Returns zero on success and negative values on failure.
592 *
593 */
594int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
595{
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500596 int ret_val;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400597 struct cipso_v4_doi *doi_def;
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500598 struct audit_buffer *audit_buf;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400599
600 spin_lock(&cipso_v4_doi_list_lock);
601 doi_def = cipso_v4_doi_search(doi);
602 if (doi_def == NULL) {
603 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500604 ret_val = -ENOENT;
605 goto doi_remove_return;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400606 }
607 if (!atomic_dec_and_test(&doi_def->refcount)) {
608 spin_unlock(&cipso_v4_doi_list_lock);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500609 ret_val = -EBUSY;
610 goto doi_remove_return;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400611 }
612 list_del_rcu(&doi_def->list);
613 spin_unlock(&cipso_v4_doi_list_lock);
614
615 cipso_v4_cache_invalidate();
616 call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500617 ret_val = 0;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400618
Paul Moore6c2e8ac2008-12-31 12:54:11 -0500619doi_remove_return:
620 audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info);
621 if (audit_buf != NULL) {
622 audit_log_format(audit_buf,
623 " cipso_doi=%u res=%u",
624 doi, ret_val == 0 ? 1 : 0);
625 audit_log_end(audit_buf);
626 }
627
628 return ret_val;
Paul Mooreb1edeb12008-10-10 10:16:31 -0400629}
630
631/**
632 * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition
Paul Moore446fda42006-08-03 16:48:06 -0700633 * @doi: the DOI value
634 *
635 * Description:
636 * Searches for a valid DOI definition and if one is found it is returned to
637 * the caller. Otherwise NULL is returned. The caller must ensure that
Paul Mooreb1edeb12008-10-10 10:16:31 -0400638 * rcu_read_lock() is held while accessing the returned definition and the DOI
639 * definition reference count is decremented when the caller is done.
Paul Moore446fda42006-08-03 16:48:06 -0700640 *
641 */
642struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
643{
Paul Mooreb1edeb12008-10-10 10:16:31 -0400644 struct cipso_v4_doi *doi_def;
645
646 rcu_read_lock();
647 doi_def = cipso_v4_doi_search(doi);
648 if (doi_def == NULL)
649 goto doi_getdef_return;
650 if (!atomic_inc_not_zero(&doi_def->refcount))
651 doi_def = NULL;
652
653doi_getdef_return:
654 rcu_read_unlock();
655 return doi_def;
656}
657
658/**
659 * cipso_v4_doi_putdef - Releases a reference for the given DOI definition
660 * @doi_def: the DOI definition
661 *
662 * Description:
663 * Releases a DOI definition reference obtained from cipso_v4_doi_getdef().
664 *
665 */
666void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
667{
668 if (doi_def == NULL)
669 return;
670
671 if (!atomic_dec_and_test(&doi_def->refcount))
672 return;
673 spin_lock(&cipso_v4_doi_list_lock);
674 list_del_rcu(&doi_def->list);
675 spin_unlock(&cipso_v4_doi_list_lock);
676
677 cipso_v4_cache_invalidate();
678 call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
Paul Moore446fda42006-08-03 16:48:06 -0700679}
680
681/**
Paul Moorefcd48282006-09-25 15:56:09 -0700682 * cipso_v4_doi_walk - Iterate through the DOI definitions
683 * @skip_cnt: skip past this number of DOI definitions, updated
684 * @callback: callback for each DOI definition
685 * @cb_arg: argument for the callback function
Paul Moore446fda42006-08-03 16:48:06 -0700686 *
687 * Description:
Paul Moorefcd48282006-09-25 15:56:09 -0700688 * Iterate over the DOI definition list, skipping the first @skip_cnt entries.
689 * For each entry call @callback, if @callback returns a negative value stop
690 * 'walking' through the list and return. Updates the value in @skip_cnt upon
691 * return. Returns zero on success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -0700692 *
693 */
Paul Moorefcd48282006-09-25 15:56:09 -0700694int cipso_v4_doi_walk(u32 *skip_cnt,
695 int (*callback) (struct cipso_v4_doi *doi_def, void *arg),
696 void *cb_arg)
Paul Moore446fda42006-08-03 16:48:06 -0700697{
Paul Moorefcd48282006-09-25 15:56:09 -0700698 int ret_val = -ENOENT;
Paul Moore446fda42006-08-03 16:48:06 -0700699 u32 doi_cnt = 0;
Paul Moorefcd48282006-09-25 15:56:09 -0700700 struct cipso_v4_doi *iter_doi;
Paul Moore446fda42006-08-03 16:48:06 -0700701
702 rcu_read_lock();
Paul Moorefcd48282006-09-25 15:56:09 -0700703 list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
Paul Mooreb1edeb12008-10-10 10:16:31 -0400704 if (atomic_read(&iter_doi->refcount) > 0) {
Paul Moorefcd48282006-09-25 15:56:09 -0700705 if (doi_cnt++ < *skip_cnt)
706 continue;
707 ret_val = callback(iter_doi, cb_arg);
708 if (ret_val < 0) {
709 doi_cnt--;
710 goto doi_walk_return;
Paul Moore446fda42006-08-03 16:48:06 -0700711 }
Paul Moorefcd48282006-09-25 15:56:09 -0700712 }
Paul Moore446fda42006-08-03 16:48:06 -0700713
Paul Moorefcd48282006-09-25 15:56:09 -0700714doi_walk_return:
Paul Moore446fda42006-08-03 16:48:06 -0700715 rcu_read_unlock();
Paul Moorefcd48282006-09-25 15:56:09 -0700716 *skip_cnt = doi_cnt;
717 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700718}
719
Paul Moore446fda42006-08-03 16:48:06 -0700720/*
721 * Label Mapping Functions
722 */
723
724/**
725 * cipso_v4_map_lvl_valid - Checks to see if the given level is understood
726 * @doi_def: the DOI definition
727 * @level: the level to check
728 *
729 * Description:
730 * Checks the given level against the given DOI definition and returns a
731 * negative value if the level does not have a valid mapping and a zero value
732 * if the level is defined by the DOI.
733 *
734 */
735static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level)
736{
737 switch (doi_def->type) {
738 case CIPSO_V4_MAP_PASS:
739 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400740 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700741 if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)
742 return 0;
743 break;
744 }
745
746 return -EFAULT;
747}
748
749/**
750 * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network
751 * @doi_def: the DOI definition
752 * @host_lvl: the host MLS level
753 * @net_lvl: the network/CIPSO MLS level
754 *
755 * Description:
756 * Perform a label mapping to translate a local MLS level to the correct
757 * CIPSO level using the given DOI definition. Returns zero on success,
758 * negative values otherwise.
759 *
760 */
761static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def,
762 u32 host_lvl,
763 u32 *net_lvl)
764{
765 switch (doi_def->type) {
766 case CIPSO_V4_MAP_PASS:
767 *net_lvl = host_lvl;
768 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400769 case CIPSO_V4_MAP_TRANS:
Paul Moorec6387a82007-03-02 13:19:02 -0800770 if (host_lvl < doi_def->map.std->lvl.local_size &&
771 doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) {
Paul Moore446fda42006-08-03 16:48:06 -0700772 *net_lvl = doi_def->map.std->lvl.local[host_lvl];
773 return 0;
774 }
Paul Moorec6387a82007-03-02 13:19:02 -0800775 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700776 }
777
778 return -EINVAL;
779}
780
781/**
782 * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host
783 * @doi_def: the DOI definition
784 * @net_lvl: the network/CIPSO MLS level
785 * @host_lvl: the host MLS level
786 *
787 * Description:
788 * Perform a label mapping to translate a CIPSO level to the correct local MLS
789 * level using the given DOI definition. Returns zero on success, negative
790 * values otherwise.
791 *
792 */
793static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def,
794 u32 net_lvl,
795 u32 *host_lvl)
796{
797 struct cipso_v4_std_map_tbl *map_tbl;
798
799 switch (doi_def->type) {
800 case CIPSO_V4_MAP_PASS:
801 *host_lvl = net_lvl;
802 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400803 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700804 map_tbl = doi_def->map.std;
805 if (net_lvl < map_tbl->lvl.cipso_size &&
806 map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) {
807 *host_lvl = doi_def->map.std->lvl.cipso[net_lvl];
808 return 0;
809 }
Paul Moorec6387a82007-03-02 13:19:02 -0800810 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700811 }
812
813 return -EINVAL;
814}
815
816/**
817 * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid
818 * @doi_def: the DOI definition
819 * @bitmap: category bitmap
820 * @bitmap_len: bitmap length in bytes
821 *
822 * Description:
823 * Checks the given category bitmap against the given DOI definition and
824 * returns a negative value if any of the categories in the bitmap do not have
825 * a valid mapping and a zero value if all of the categories are valid.
826 *
827 */
828static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def,
829 const unsigned char *bitmap,
830 u32 bitmap_len)
831{
832 int cat = -1;
833 u32 bitmap_len_bits = bitmap_len * 8;
Paul Moore044a68e2006-10-11 19:10:47 -0400834 u32 cipso_cat_size;
835 u32 *cipso_array;
Paul Moore446fda42006-08-03 16:48:06 -0700836
837 switch (doi_def->type) {
838 case CIPSO_V4_MAP_PASS:
839 return 0;
Paul Moore15c45f72008-10-10 10:16:34 -0400840 case CIPSO_V4_MAP_TRANS:
Paul Moore044a68e2006-10-11 19:10:47 -0400841 cipso_cat_size = doi_def->map.std->cat.cipso_size;
842 cipso_array = doi_def->map.std->cat.cipso;
Paul Moore446fda42006-08-03 16:48:06 -0700843 for (;;) {
844 cat = cipso_v4_bitmap_walk(bitmap,
845 bitmap_len_bits,
846 cat + 1,
847 1);
848 if (cat < 0)
849 break;
850 if (cat >= cipso_cat_size ||
851 cipso_array[cat] >= CIPSO_V4_INV_CAT)
852 return -EFAULT;
853 }
854
855 if (cat == -1)
856 return 0;
857 break;
858 }
859
860 return -EFAULT;
861}
862
863/**
864 * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network
865 * @doi_def: the DOI definition
Paul Moore02752762006-11-29 13:18:18 -0500866 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -0700867 * @net_cat: the zero'd out category bitmap in network/CIPSO format
868 * @net_cat_len: the length of the CIPSO bitmap in bytes
869 *
870 * Description:
871 * Perform a label mapping to translate a local MLS category bitmap to the
872 * correct CIPSO bitmap using the given DOI definition. Returns the minimum
873 * size in bytes of the network bitmap on success, negative values otherwise.
874 *
875 */
876static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def,
Paul Moore02752762006-11-29 13:18:18 -0500877 const struct netlbl_lsm_secattr *secattr,
Paul Moore446fda42006-08-03 16:48:06 -0700878 unsigned char *net_cat,
879 u32 net_cat_len)
880{
881 int host_spot = -1;
Paul Moore02752762006-11-29 13:18:18 -0500882 u32 net_spot = CIPSO_V4_INV_CAT;
Paul Moore446fda42006-08-03 16:48:06 -0700883 u32 net_spot_max = 0;
Paul Moore446fda42006-08-03 16:48:06 -0700884 u32 net_clen_bits = net_cat_len * 8;
Paul Moore02752762006-11-29 13:18:18 -0500885 u32 host_cat_size = 0;
886 u32 *host_cat_array = NULL;
Paul Moore446fda42006-08-03 16:48:06 -0700887
Paul Moore15c45f72008-10-10 10:16:34 -0400888 if (doi_def->type == CIPSO_V4_MAP_TRANS) {
Paul Moore044a68e2006-10-11 19:10:47 -0400889 host_cat_size = doi_def->map.std->cat.local_size;
890 host_cat_array = doi_def->map.std->cat.local;
Paul Moore02752762006-11-29 13:18:18 -0500891 }
892
893 for (;;) {
Paul Moore16efd452008-01-29 08:37:59 -0500894 host_spot = netlbl_secattr_catmap_walk(secattr->attr.mls.cat,
Paul Moore02752762006-11-29 13:18:18 -0500895 host_spot + 1);
896 if (host_spot < 0)
897 break;
898
899 switch (doi_def->type) {
900 case CIPSO_V4_MAP_PASS:
901 net_spot = host_spot;
902 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400903 case CIPSO_V4_MAP_TRANS:
Paul Moore446fda42006-08-03 16:48:06 -0700904 if (host_spot >= host_cat_size)
905 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700906 net_spot = host_cat_array[host_spot];
Paul Moore9fade4b2006-11-17 17:38:50 -0500907 if (net_spot >= CIPSO_V4_INV_CAT)
908 return -EPERM;
Paul Moore02752762006-11-29 13:18:18 -0500909 break;
Paul Moore446fda42006-08-03 16:48:06 -0700910 }
Paul Moore02752762006-11-29 13:18:18 -0500911 if (net_spot >= net_clen_bits)
912 return -ENOSPC;
913 cipso_v4_bitmap_setbit(net_cat, net_spot, 1);
Paul Moore446fda42006-08-03 16:48:06 -0700914
Paul Moore02752762006-11-29 13:18:18 -0500915 if (net_spot > net_spot_max)
916 net_spot_max = net_spot;
Paul Moore446fda42006-08-03 16:48:06 -0700917 }
918
Paul Moore02752762006-11-29 13:18:18 -0500919 if (++net_spot_max % 8)
920 return net_spot_max / 8 + 1;
921 return net_spot_max / 8;
Paul Moore446fda42006-08-03 16:48:06 -0700922}
923
924/**
925 * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host
926 * @doi_def: the DOI definition
927 * @net_cat: the category bitmap in network/CIPSO format
928 * @net_cat_len: the length of the CIPSO bitmap in bytes
Paul Moore02752762006-11-29 13:18:18 -0500929 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -0700930 *
931 * Description:
932 * Perform a label mapping to translate a CIPSO bitmap to the correct local
Paul Moore02752762006-11-29 13:18:18 -0500933 * MLS category bitmap using the given DOI definition. Returns zero on
934 * success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -0700935 *
936 */
937static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
938 const unsigned char *net_cat,
939 u32 net_cat_len,
Paul Moore02752762006-11-29 13:18:18 -0500940 struct netlbl_lsm_secattr *secattr)
Paul Moore446fda42006-08-03 16:48:06 -0700941{
Paul Moore02752762006-11-29 13:18:18 -0500942 int ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700943 int net_spot = -1;
Paul Moore02752762006-11-29 13:18:18 -0500944 u32 host_spot = CIPSO_V4_INV_CAT;
Paul Moore446fda42006-08-03 16:48:06 -0700945 u32 net_clen_bits = net_cat_len * 8;
Paul Moore02752762006-11-29 13:18:18 -0500946 u32 net_cat_size = 0;
947 u32 *net_cat_array = NULL;
Paul Moore446fda42006-08-03 16:48:06 -0700948
Paul Moore15c45f72008-10-10 10:16:34 -0400949 if (doi_def->type == CIPSO_V4_MAP_TRANS) {
Paul Moore044a68e2006-10-11 19:10:47 -0400950 net_cat_size = doi_def->map.std->cat.cipso_size;
951 net_cat_array = doi_def->map.std->cat.cipso;
Paul Moore02752762006-11-29 13:18:18 -0500952 }
Paul Moore446fda42006-08-03 16:48:06 -0700953
Paul Moore02752762006-11-29 13:18:18 -0500954 for (;;) {
955 net_spot = cipso_v4_bitmap_walk(net_cat,
956 net_clen_bits,
957 net_spot + 1,
958 1);
959 if (net_spot < 0) {
960 if (net_spot == -2)
961 return -EFAULT;
962 return 0;
963 }
964
965 switch (doi_def->type) {
966 case CIPSO_V4_MAP_PASS:
967 host_spot = net_spot;
968 break;
Paul Moore15c45f72008-10-10 10:16:34 -0400969 case CIPSO_V4_MAP_TRANS:
Paul Moore02752762006-11-29 13:18:18 -0500970 if (net_spot >= net_cat_size)
971 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -0700972 host_spot = net_cat_array[net_spot];
Paul Moore9fade4b2006-11-17 17:38:50 -0500973 if (host_spot >= CIPSO_V4_INV_CAT)
974 return -EPERM;
Paul Moore02752762006-11-29 13:18:18 -0500975 break;
Paul Moore446fda42006-08-03 16:48:06 -0700976 }
Paul Moore16efd452008-01-29 08:37:59 -0500977 ret_val = netlbl_secattr_catmap_setbit(secattr->attr.mls.cat,
Paul Moore02752762006-11-29 13:18:18 -0500978 host_spot,
979 GFP_ATOMIC);
980 if (ret_val != 0)
981 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -0700982 }
983
984 return -EINVAL;
985}
986
Paul Moore654bbc22006-11-29 13:18:19 -0500987/**
988 * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid
989 * @doi_def: the DOI definition
990 * @enumcat: category list
991 * @enumcat_len: length of the category list in bytes
992 *
993 * Description:
994 * Checks the given categories against the given DOI definition and returns a
995 * negative value if any of the categories do not have a valid mapping and a
996 * zero value if all of the categories are valid.
997 *
998 */
999static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def,
1000 const unsigned char *enumcat,
1001 u32 enumcat_len)
1002{
1003 u16 cat;
1004 int cat_prev = -1;
1005 u32 iter;
1006
1007 if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01)
1008 return -EFAULT;
1009
1010 for (iter = 0; iter < enumcat_len; iter += 2) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001011 cat = get_unaligned_be16(&enumcat[iter]);
Paul Moore654bbc22006-11-29 13:18:19 -05001012 if (cat <= cat_prev)
1013 return -EFAULT;
1014 cat_prev = cat;
1015 }
1016
1017 return 0;
1018}
1019
1020/**
1021 * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network
1022 * @doi_def: the DOI definition
1023 * @secattr: the security attributes
1024 * @net_cat: the zero'd out category list in network/CIPSO format
1025 * @net_cat_len: the length of the CIPSO category list in bytes
1026 *
1027 * Description:
1028 * Perform a label mapping to translate a local MLS category bitmap to the
1029 * correct CIPSO category list using the given DOI definition. Returns the
1030 * size in bytes of the network category bitmap on success, negative values
1031 * otherwise.
1032 *
1033 */
1034static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def,
1035 const struct netlbl_lsm_secattr *secattr,
1036 unsigned char *net_cat,
1037 u32 net_cat_len)
1038{
1039 int cat = -1;
1040 u32 cat_iter = 0;
1041
1042 for (;;) {
Paul Moore16efd452008-01-29 08:37:59 -05001043 cat = netlbl_secattr_catmap_walk(secattr->attr.mls.cat,
1044 cat + 1);
Paul Moore654bbc22006-11-29 13:18:19 -05001045 if (cat < 0)
1046 break;
1047 if ((cat_iter + 2) > net_cat_len)
1048 return -ENOSPC;
1049
1050 *((__be16 *)&net_cat[cat_iter]) = htons(cat);
1051 cat_iter += 2;
1052 }
1053
1054 return cat_iter;
1055}
1056
1057/**
1058 * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host
1059 * @doi_def: the DOI definition
1060 * @net_cat: the category list in network/CIPSO format
1061 * @net_cat_len: the length of the CIPSO bitmap in bytes
1062 * @secattr: the security attributes
1063 *
1064 * Description:
1065 * Perform a label mapping to translate a CIPSO category list to the correct
1066 * local MLS category bitmap using the given DOI definition. Returns zero on
1067 * success, negative values on failure.
1068 *
1069 */
1070static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def,
1071 const unsigned char *net_cat,
1072 u32 net_cat_len,
1073 struct netlbl_lsm_secattr *secattr)
1074{
1075 int ret_val;
1076 u32 iter;
1077
1078 for (iter = 0; iter < net_cat_len; iter += 2) {
Paul Moore16efd452008-01-29 08:37:59 -05001079 ret_val = netlbl_secattr_catmap_setbit(secattr->attr.mls.cat,
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001080 get_unaligned_be16(&net_cat[iter]),
Paul Moore50e5d352007-06-07 18:38:14 -07001081 GFP_ATOMIC);
Paul Moore654bbc22006-11-29 13:18:19 -05001082 if (ret_val != 0)
1083 return ret_val;
1084 }
1085
1086 return 0;
1087}
1088
Paul Moore484b3662006-11-29 13:18:20 -05001089/**
1090 * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid
1091 * @doi_def: the DOI definition
1092 * @rngcat: category list
1093 * @rngcat_len: length of the category list in bytes
1094 *
1095 * Description:
1096 * Checks the given categories against the given DOI definition and returns a
1097 * negative value if any of the categories do not have a valid mapping and a
1098 * zero value if all of the categories are valid.
1099 *
1100 */
1101static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def,
1102 const unsigned char *rngcat,
1103 u32 rngcat_len)
1104{
1105 u16 cat_high;
1106 u16 cat_low;
1107 u32 cat_prev = CIPSO_V4_MAX_REM_CATS + 1;
1108 u32 iter;
1109
1110 if (doi_def->type != CIPSO_V4_MAP_PASS || rngcat_len & 0x01)
1111 return -EFAULT;
1112
1113 for (iter = 0; iter < rngcat_len; iter += 4) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001114 cat_high = get_unaligned_be16(&rngcat[iter]);
Paul Moore484b3662006-11-29 13:18:20 -05001115 if ((iter + 4) <= rngcat_len)
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001116 cat_low = get_unaligned_be16(&rngcat[iter + 2]);
Paul Moore484b3662006-11-29 13:18:20 -05001117 else
1118 cat_low = 0;
1119
1120 if (cat_high > cat_prev)
1121 return -EFAULT;
1122
1123 cat_prev = cat_low;
1124 }
1125
1126 return 0;
1127}
1128
1129/**
1130 * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network
1131 * @doi_def: the DOI definition
1132 * @secattr: the security attributes
1133 * @net_cat: the zero'd out category list in network/CIPSO format
1134 * @net_cat_len: the length of the CIPSO category list in bytes
1135 *
1136 * Description:
1137 * Perform a label mapping to translate a local MLS category bitmap to the
1138 * correct CIPSO category list using the given DOI definition. Returns the
1139 * size in bytes of the network category bitmap on success, negative values
1140 * otherwise.
1141 *
1142 */
1143static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def,
1144 const struct netlbl_lsm_secattr *secattr,
1145 unsigned char *net_cat,
1146 u32 net_cat_len)
1147{
Paul Moore484b3662006-11-29 13:18:20 -05001148 int iter = -1;
Paul Mooref998e8c2007-02-28 15:14:20 -05001149 u16 array[CIPSO_V4_TAG_RNG_CAT_MAX * 2];
Paul Moore484b3662006-11-29 13:18:20 -05001150 u32 array_cnt = 0;
1151 u32 cat_size = 0;
1152
Paul Mooref998e8c2007-02-28 15:14:20 -05001153 /* make sure we don't overflow the 'array[]' variable */
Paul Moore128c6b62007-02-28 15:14:21 -05001154 if (net_cat_len >
1155 (CIPSO_V4_OPT_LEN_MAX - CIPSO_V4_HDR_LEN - CIPSO_V4_TAG_RNG_BLEN))
1156 return -ENOSPC;
Paul Moore484b3662006-11-29 13:18:20 -05001157
1158 for (;;) {
Paul Moore16efd452008-01-29 08:37:59 -05001159 iter = netlbl_secattr_catmap_walk(secattr->attr.mls.cat,
1160 iter + 1);
Paul Moore484b3662006-11-29 13:18:20 -05001161 if (iter < 0)
1162 break;
1163 cat_size += (iter == 0 ? 0 : sizeof(u16));
1164 if (cat_size > net_cat_len)
1165 return -ENOSPC;
1166 array[array_cnt++] = iter;
1167
Paul Moore16efd452008-01-29 08:37:59 -05001168 iter = netlbl_secattr_catmap_walk_rng(secattr->attr.mls.cat,
1169 iter);
Paul Moore484b3662006-11-29 13:18:20 -05001170 if (iter < 0)
1171 return -EFAULT;
1172 cat_size += sizeof(u16);
1173 if (cat_size > net_cat_len)
1174 return -ENOSPC;
1175 array[array_cnt++] = iter;
1176 }
1177
1178 for (iter = 0; array_cnt > 0;) {
1179 *((__be16 *)&net_cat[iter]) = htons(array[--array_cnt]);
1180 iter += 2;
1181 array_cnt--;
1182 if (array[array_cnt] != 0) {
1183 *((__be16 *)&net_cat[iter]) = htons(array[array_cnt]);
1184 iter += 2;
1185 }
1186 }
1187
1188 return cat_size;
1189}
1190
1191/**
1192 * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host
1193 * @doi_def: the DOI definition
1194 * @net_cat: the category list in network/CIPSO format
1195 * @net_cat_len: the length of the CIPSO bitmap in bytes
1196 * @secattr: the security attributes
1197 *
1198 * Description:
1199 * Perform a label mapping to translate a CIPSO category list to the correct
1200 * local MLS category bitmap using the given DOI definition. Returns zero on
1201 * success, negative values on failure.
1202 *
1203 */
1204static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def,
1205 const unsigned char *net_cat,
1206 u32 net_cat_len,
1207 struct netlbl_lsm_secattr *secattr)
1208{
1209 int ret_val;
1210 u32 net_iter;
1211 u16 cat_low;
1212 u16 cat_high;
1213
Stephen Hemminger132adf52007-03-08 20:44:43 -08001214 for (net_iter = 0; net_iter < net_cat_len; net_iter += 4) {
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001215 cat_high = get_unaligned_be16(&net_cat[net_iter]);
Paul Moore484b3662006-11-29 13:18:20 -05001216 if ((net_iter + 4) <= net_cat_len)
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001217 cat_low = get_unaligned_be16(&net_cat[net_iter + 2]);
Paul Moore484b3662006-11-29 13:18:20 -05001218 else
1219 cat_low = 0;
1220
Paul Moore16efd452008-01-29 08:37:59 -05001221 ret_val = netlbl_secattr_catmap_setrng(secattr->attr.mls.cat,
Paul Moore484b3662006-11-29 13:18:20 -05001222 cat_low,
1223 cat_high,
1224 GFP_ATOMIC);
1225 if (ret_val != 0)
1226 return ret_val;
1227 }
1228
1229 return 0;
1230}
1231
Paul Moore446fda42006-08-03 16:48:06 -07001232/*
1233 * Protocol Handling Functions
1234 */
1235
Paul Moore446fda42006-08-03 16:48:06 -07001236/**
1237 * cipso_v4_gentag_hdr - Generate a CIPSO option header
1238 * @doi_def: the DOI definition
Paul Moore91b1ed02006-11-17 17:38:49 -05001239 * @len: the total tag length in bytes, not including this header
Paul Moore446fda42006-08-03 16:48:06 -07001240 * @buf: the CIPSO option buffer
1241 *
1242 * Description:
Paul Moore91b1ed02006-11-17 17:38:49 -05001243 * Write a CIPSO header into the beginning of @buffer.
Paul Moore446fda42006-08-03 16:48:06 -07001244 *
1245 */
Paul Moore91b1ed02006-11-17 17:38:49 -05001246static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def,
1247 unsigned char *buf,
1248 u32 len)
Paul Moore446fda42006-08-03 16:48:06 -07001249{
Paul Moore446fda42006-08-03 16:48:06 -07001250 buf[0] = IPOPT_CIPSO;
1251 buf[1] = CIPSO_V4_HDR_LEN + len;
Al Viro714e85b2006-11-14 20:51:49 -08001252 *(__be32 *)&buf[2] = htonl(doi_def->doi);
Paul Moore446fda42006-08-03 16:48:06 -07001253}
1254
Paul Moore446fda42006-08-03 16:48:06 -07001255/**
1256 * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1)
1257 * @doi_def: the DOI definition
1258 * @secattr: the security attributes
1259 * @buffer: the option buffer
1260 * @buffer_len: length of buffer in bytes
1261 *
1262 * Description:
1263 * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The
1264 * actual buffer length may be larger than the indicated size due to
Paul Moore91b1ed02006-11-17 17:38:49 -05001265 * translation between host and network category bitmaps. Returns the size of
1266 * the tag on success, negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -07001267 *
1268 */
1269static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
1270 const struct netlbl_lsm_secattr *secattr,
Paul Moore91b1ed02006-11-17 17:38:49 -05001271 unsigned char *buffer,
1272 u32 buffer_len)
Paul Moore446fda42006-08-03 16:48:06 -07001273{
Paul Moore701a90b2006-11-17 17:38:46 -05001274 int ret_val;
Paul Moore91b1ed02006-11-17 17:38:49 -05001275 u32 tag_len;
Paul Moore446fda42006-08-03 16:48:06 -07001276 u32 level;
1277
Paul Moore701a90b2006-11-17 17:38:46 -05001278 if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0)
1279 return -EPERM;
1280
Paul Moore16efd452008-01-29 08:37:59 -05001281 ret_val = cipso_v4_map_lvl_hton(doi_def,
1282 secattr->attr.mls.lvl,
1283 &level);
Paul Moore91b1ed02006-11-17 17:38:49 -05001284 if (ret_val != 0)
1285 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001286
Paul Moore91b1ed02006-11-17 17:38:49 -05001287 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
Paul Moore446fda42006-08-03 16:48:06 -07001288 ret_val = cipso_v4_map_cat_rbm_hton(doi_def,
Paul Moore02752762006-11-29 13:18:18 -05001289 secattr,
Paul Moore91b1ed02006-11-17 17:38:49 -05001290 &buffer[4],
1291 buffer_len - 4);
Paul Moore446fda42006-08-03 16:48:06 -07001292 if (ret_val < 0)
Paul Moore91b1ed02006-11-17 17:38:49 -05001293 return ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001294
1295 /* This will send packets using the "optimized" format when
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001296 * possible as specified in section 3.4.2.6 of the
Paul Moore446fda42006-08-03 16:48:06 -07001297 * CIPSO draft. */
Paul Moore701a90b2006-11-17 17:38:46 -05001298 if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
Paul Moore91b1ed02006-11-17 17:38:49 -05001299 tag_len = 14;
Paul Moore701a90b2006-11-17 17:38:46 -05001300 else
Paul Moore91b1ed02006-11-17 17:38:49 -05001301 tag_len = 4 + ret_val;
1302 } else
1303 tag_len = 4;
Paul Moore446fda42006-08-03 16:48:06 -07001304
Paul Moore15c45f72008-10-10 10:16:34 -04001305 buffer[0] = CIPSO_V4_TAG_RBITMAP;
Paul Moore91b1ed02006-11-17 17:38:49 -05001306 buffer[1] = tag_len;
1307 buffer[3] = level;
Paul Moore446fda42006-08-03 16:48:06 -07001308
Paul Moore91b1ed02006-11-17 17:38:49 -05001309 return tag_len;
Paul Moore446fda42006-08-03 16:48:06 -07001310}
1311
1312/**
1313 * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag
1314 * @doi_def: the DOI definition
1315 * @tag: the CIPSO tag
1316 * @secattr: the security attributes
1317 *
1318 * Description:
1319 * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security
1320 * attributes in @secattr. Return zero on success, negatives values on
1321 * failure.
1322 *
1323 */
1324static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def,
1325 const unsigned char *tag,
1326 struct netlbl_lsm_secattr *secattr)
1327{
1328 int ret_val;
1329 u8 tag_len = tag[1];
1330 u32 level;
1331
1332 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1333 if (ret_val != 0)
1334 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001335 secattr->attr.mls.lvl = level;
Paul Moore701a90b2006-11-17 17:38:46 -05001336 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
Paul Moore446fda42006-08-03 16:48:06 -07001337
1338 if (tag_len > 4) {
Paul Moore16efd452008-01-29 08:37:59 -05001339 secattr->attr.mls.cat =
1340 netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1341 if (secattr->attr.mls.cat == NULL)
Paul Moore446fda42006-08-03 16:48:06 -07001342 return -ENOMEM;
1343
1344 ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def,
1345 &tag[4],
1346 tag_len - 4,
Paul Moore02752762006-11-29 13:18:18 -05001347 secattr);
1348 if (ret_val != 0) {
Paul Moore16efd452008-01-29 08:37:59 -05001349 netlbl_secattr_catmap_free(secattr->attr.mls.cat);
Paul Moore446fda42006-08-03 16:48:06 -07001350 return ret_val;
1351 }
Paul Moore02752762006-11-29 13:18:18 -05001352
1353 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
Paul Moore446fda42006-08-03 16:48:06 -07001354 }
1355
1356 return 0;
1357}
1358
1359/**
Paul Moore654bbc22006-11-29 13:18:19 -05001360 * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2)
1361 * @doi_def: the DOI definition
1362 * @secattr: the security attributes
1363 * @buffer: the option buffer
1364 * @buffer_len: length of buffer in bytes
1365 *
1366 * Description:
1367 * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the
1368 * size of the tag on success, negative values on failure.
1369 *
1370 */
1371static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def,
1372 const struct netlbl_lsm_secattr *secattr,
1373 unsigned char *buffer,
1374 u32 buffer_len)
1375{
1376 int ret_val;
1377 u32 tag_len;
1378 u32 level;
1379
1380 if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL))
1381 return -EPERM;
1382
Paul Moore16efd452008-01-29 08:37:59 -05001383 ret_val = cipso_v4_map_lvl_hton(doi_def,
1384 secattr->attr.mls.lvl,
1385 &level);
Paul Moore654bbc22006-11-29 13:18:19 -05001386 if (ret_val != 0)
1387 return ret_val;
1388
1389 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
1390 ret_val = cipso_v4_map_cat_enum_hton(doi_def,
1391 secattr,
1392 &buffer[4],
1393 buffer_len - 4);
1394 if (ret_val < 0)
1395 return ret_val;
1396
1397 tag_len = 4 + ret_val;
1398 } else
1399 tag_len = 4;
1400
Paul Moore15c45f72008-10-10 10:16:34 -04001401 buffer[0] = CIPSO_V4_TAG_ENUM;
Paul Moore654bbc22006-11-29 13:18:19 -05001402 buffer[1] = tag_len;
1403 buffer[3] = level;
1404
1405 return tag_len;
1406}
1407
1408/**
1409 * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag
1410 * @doi_def: the DOI definition
1411 * @tag: the CIPSO tag
1412 * @secattr: the security attributes
1413 *
1414 * Description:
1415 * Parse a CIPSO enumerated tag (tag type #2) and return the security
1416 * attributes in @secattr. Return zero on success, negatives values on
1417 * failure.
1418 *
1419 */
1420static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def,
1421 const unsigned char *tag,
1422 struct netlbl_lsm_secattr *secattr)
1423{
1424 int ret_val;
1425 u8 tag_len = tag[1];
1426 u32 level;
1427
1428 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1429 if (ret_val != 0)
1430 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001431 secattr->attr.mls.lvl = level;
Paul Moore654bbc22006-11-29 13:18:19 -05001432 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
1433
1434 if (tag_len > 4) {
Paul Moore16efd452008-01-29 08:37:59 -05001435 secattr->attr.mls.cat =
1436 netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1437 if (secattr->attr.mls.cat == NULL)
Paul Moore654bbc22006-11-29 13:18:19 -05001438 return -ENOMEM;
1439
1440 ret_val = cipso_v4_map_cat_enum_ntoh(doi_def,
1441 &tag[4],
1442 tag_len - 4,
1443 secattr);
1444 if (ret_val != 0) {
Paul Moore16efd452008-01-29 08:37:59 -05001445 netlbl_secattr_catmap_free(secattr->attr.mls.cat);
Paul Moore654bbc22006-11-29 13:18:19 -05001446 return ret_val;
1447 }
1448
1449 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
1450 }
1451
1452 return 0;
1453}
1454
1455/**
Paul Moore484b3662006-11-29 13:18:20 -05001456 * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5)
1457 * @doi_def: the DOI definition
1458 * @secattr: the security attributes
1459 * @buffer: the option buffer
1460 * @buffer_len: length of buffer in bytes
1461 *
1462 * Description:
1463 * Generate a CIPSO option using the ranged tag, tag type #5. Returns the
1464 * size of the tag on success, negative values on failure.
1465 *
1466 */
1467static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def,
1468 const struct netlbl_lsm_secattr *secattr,
1469 unsigned char *buffer,
1470 u32 buffer_len)
1471{
1472 int ret_val;
1473 u32 tag_len;
1474 u32 level;
1475
1476 if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL))
1477 return -EPERM;
1478
Paul Moore16efd452008-01-29 08:37:59 -05001479 ret_val = cipso_v4_map_lvl_hton(doi_def,
1480 secattr->attr.mls.lvl,
1481 &level);
Paul Moore484b3662006-11-29 13:18:20 -05001482 if (ret_val != 0)
1483 return ret_val;
1484
1485 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
1486 ret_val = cipso_v4_map_cat_rng_hton(doi_def,
1487 secattr,
1488 &buffer[4],
1489 buffer_len - 4);
1490 if (ret_val < 0)
1491 return ret_val;
1492
1493 tag_len = 4 + ret_val;
1494 } else
1495 tag_len = 4;
1496
Paul Moore15c45f72008-10-10 10:16:34 -04001497 buffer[0] = CIPSO_V4_TAG_RANGE;
Paul Moore484b3662006-11-29 13:18:20 -05001498 buffer[1] = tag_len;
1499 buffer[3] = level;
1500
1501 return tag_len;
1502}
1503
1504/**
1505 * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag
1506 * @doi_def: the DOI definition
1507 * @tag: the CIPSO tag
1508 * @secattr: the security attributes
1509 *
1510 * Description:
1511 * Parse a CIPSO ranged tag (tag type #5) and return the security attributes
1512 * in @secattr. Return zero on success, negatives values on failure.
1513 *
1514 */
1515static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def,
1516 const unsigned char *tag,
1517 struct netlbl_lsm_secattr *secattr)
1518{
1519 int ret_val;
1520 u8 tag_len = tag[1];
1521 u32 level;
1522
1523 ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
1524 if (ret_val != 0)
1525 return ret_val;
Paul Moore16efd452008-01-29 08:37:59 -05001526 secattr->attr.mls.lvl = level;
Paul Moore484b3662006-11-29 13:18:20 -05001527 secattr->flags |= NETLBL_SECATTR_MLS_LVL;
1528
1529 if (tag_len > 4) {
Paul Moore16efd452008-01-29 08:37:59 -05001530 secattr->attr.mls.cat =
1531 netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1532 if (secattr->attr.mls.cat == NULL)
Paul Moore484b3662006-11-29 13:18:20 -05001533 return -ENOMEM;
1534
1535 ret_val = cipso_v4_map_cat_rng_ntoh(doi_def,
1536 &tag[4],
1537 tag_len - 4,
1538 secattr);
1539 if (ret_val != 0) {
Paul Moore16efd452008-01-29 08:37:59 -05001540 netlbl_secattr_catmap_free(secattr->attr.mls.cat);
Paul Moore484b3662006-11-29 13:18:20 -05001541 return ret_val;
1542 }
1543
1544 secattr->flags |= NETLBL_SECATTR_MLS_CAT;
1545 }
1546
1547 return 0;
1548}
1549
1550/**
Paul Moore15c45f72008-10-10 10:16:34 -04001551 * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard)
1552 * @doi_def: the DOI definition
1553 * @secattr: the security attributes
1554 * @buffer: the option buffer
1555 * @buffer_len: length of buffer in bytes
1556 *
1557 * Description:
1558 * Generate a CIPSO option using the local tag. Returns the size of the tag
1559 * on success, negative values on failure.
1560 *
1561 */
1562static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def,
1563 const struct netlbl_lsm_secattr *secattr,
1564 unsigned char *buffer,
1565 u32 buffer_len)
1566{
1567 if (!(secattr->flags & NETLBL_SECATTR_SECID))
1568 return -EPERM;
1569
1570 buffer[0] = CIPSO_V4_TAG_LOCAL;
1571 buffer[1] = CIPSO_V4_TAG_LOC_BLEN;
1572 *(u32 *)&buffer[2] = secattr->attr.secid;
1573
1574 return CIPSO_V4_TAG_LOC_BLEN;
1575}
1576
1577/**
1578 * cipso_v4_parsetag_loc - Parse a CIPSO local tag
1579 * @doi_def: the DOI definition
1580 * @tag: the CIPSO tag
1581 * @secattr: the security attributes
1582 *
1583 * Description:
1584 * Parse a CIPSO local tag and return the security attributes in @secattr.
1585 * Return zero on success, negatives values on failure.
1586 *
1587 */
1588static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def,
1589 const unsigned char *tag,
1590 struct netlbl_lsm_secattr *secattr)
1591{
1592 secattr->attr.secid = *(u32 *)&tag[2];
1593 secattr->flags |= NETLBL_SECATTR_SECID;
1594
1595 return 0;
1596}
1597
1598/**
Paul Moore446fda42006-08-03 16:48:06 -07001599 * cipso_v4_validate - Validate a CIPSO option
1600 * @option: the start of the option, on error it is set to point to the error
1601 *
1602 * Description:
1603 * This routine is called to validate a CIPSO option, it checks all of the
1604 * fields to ensure that they are at least valid, see the draft snippet below
1605 * for details. If the option is valid then a zero value is returned and
1606 * the value of @option is unchanged. If the option is invalid then a
1607 * non-zero value is returned and @option is adjusted to point to the
1608 * offending portion of the option. From the IETF draft ...
1609 *
1610 * "If any field within the CIPSO options, such as the DOI identifier, is not
1611 * recognized the IP datagram is discarded and an ICMP 'parameter problem'
1612 * (type 12) is generated and returned. The ICMP code field is set to 'bad
1613 * parameter' (code 0) and the pointer is set to the start of the CIPSO field
1614 * that is unrecognized."
1615 *
1616 */
Paul Moore15c45f72008-10-10 10:16:34 -04001617int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
Paul Moore446fda42006-08-03 16:48:06 -07001618{
1619 unsigned char *opt = *option;
1620 unsigned char *tag;
1621 unsigned char opt_iter;
1622 unsigned char err_offset = 0;
1623 u8 opt_len;
1624 u8 tag_len;
1625 struct cipso_v4_doi *doi_def = NULL;
1626 u32 tag_iter;
1627
1628 /* caller already checks for length values that are too large */
1629 opt_len = opt[1];
1630 if (opt_len < 8) {
1631 err_offset = 1;
1632 goto validate_return;
1633 }
1634
1635 rcu_read_lock();
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07001636 doi_def = cipso_v4_doi_search(get_unaligned_be32(&opt[2]));
Paul Moore446fda42006-08-03 16:48:06 -07001637 if (doi_def == NULL) {
1638 err_offset = 2;
1639 goto validate_return_locked;
1640 }
1641
Paul Moore15c45f72008-10-10 10:16:34 -04001642 opt_iter = CIPSO_V4_HDR_LEN;
Paul Moore446fda42006-08-03 16:48:06 -07001643 tag = opt + opt_iter;
1644 while (opt_iter < opt_len) {
1645 for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];)
1646 if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID ||
1647 ++tag_iter == CIPSO_V4_TAG_MAXCNT) {
1648 err_offset = opt_iter;
1649 goto validate_return_locked;
1650 }
1651
1652 tag_len = tag[1];
1653 if (tag_len > (opt_len - opt_iter)) {
1654 err_offset = opt_iter + 1;
1655 goto validate_return_locked;
1656 }
1657
1658 switch (tag[0]) {
1659 case CIPSO_V4_TAG_RBITMAP:
Paul Moore15c45f72008-10-10 10:16:34 -04001660 if (tag_len < CIPSO_V4_TAG_RBM_BLEN) {
Paul Moore446fda42006-08-03 16:48:06 -07001661 err_offset = opt_iter + 1;
1662 goto validate_return_locked;
1663 }
1664
1665 /* We are already going to do all the verification
1666 * necessary at the socket layer so from our point of
1667 * view it is safe to turn these checks off (and less
1668 * work), however, the CIPSO draft says we should do
1669 * all the CIPSO validations here but it doesn't
1670 * really specify _exactly_ what we need to validate
1671 * ... so, just make it a sysctl tunable. */
1672 if (cipso_v4_rbm_strictvalid) {
1673 if (cipso_v4_map_lvl_valid(doi_def,
1674 tag[3]) < 0) {
1675 err_offset = opt_iter + 3;
1676 goto validate_return_locked;
1677 }
Paul Moore15c45f72008-10-10 10:16:34 -04001678 if (tag_len > CIPSO_V4_TAG_RBM_BLEN &&
Paul Moore446fda42006-08-03 16:48:06 -07001679 cipso_v4_map_cat_rbm_valid(doi_def,
1680 &tag[4],
1681 tag_len - 4) < 0) {
1682 err_offset = opt_iter + 4;
1683 goto validate_return_locked;
1684 }
1685 }
1686 break;
Paul Moore654bbc22006-11-29 13:18:19 -05001687 case CIPSO_V4_TAG_ENUM:
Paul Moore15c45f72008-10-10 10:16:34 -04001688 if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) {
Paul Moore654bbc22006-11-29 13:18:19 -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_ENUM_BLEN &&
Paul Moore654bbc22006-11-29 13:18:19 -05001699 cipso_v4_map_cat_enum_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 Moore484b3662006-11-29 13:18:20 -05001706 case CIPSO_V4_TAG_RANGE:
Paul Moore15c45f72008-10-10 10:16:34 -04001707 if (tag_len < CIPSO_V4_TAG_RNG_BLEN) {
Paul Moore484b3662006-11-29 13:18:20 -05001708 err_offset = opt_iter + 1;
1709 goto validate_return_locked;
1710 }
1711
1712 if (cipso_v4_map_lvl_valid(doi_def,
1713 tag[3]) < 0) {
1714 err_offset = opt_iter + 3;
1715 goto validate_return_locked;
1716 }
Paul Moore15c45f72008-10-10 10:16:34 -04001717 if (tag_len > CIPSO_V4_TAG_RNG_BLEN &&
Paul Moore484b3662006-11-29 13:18:20 -05001718 cipso_v4_map_cat_rng_valid(doi_def,
1719 &tag[4],
1720 tag_len - 4) < 0) {
1721 err_offset = opt_iter + 4;
1722 goto validate_return_locked;
1723 }
1724 break;
Paul Moore15c45f72008-10-10 10:16:34 -04001725 case CIPSO_V4_TAG_LOCAL:
1726 /* This is a non-standard tag that we only allow for
1727 * local connections, so if the incoming interface is
1728 * not the loopback device drop the packet. */
1729 if (!(skb->dev->flags & IFF_LOOPBACK)) {
1730 err_offset = opt_iter;
1731 goto validate_return_locked;
1732 }
1733 if (tag_len != CIPSO_V4_TAG_LOC_BLEN) {
1734 err_offset = opt_iter + 1;
1735 goto validate_return_locked;
1736 }
1737 break;
Paul Moore446fda42006-08-03 16:48:06 -07001738 default:
1739 err_offset = opt_iter;
1740 goto validate_return_locked;
1741 }
1742
1743 tag += tag_len;
1744 opt_iter += tag_len;
1745 }
1746
1747validate_return_locked:
1748 rcu_read_unlock();
1749validate_return:
1750 *option = opt + err_offset;
1751 return err_offset;
1752}
1753
1754/**
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001755 * cipso_v4_error - Send the correct response for a bad packet
Paul Moore446fda42006-08-03 16:48:06 -07001756 * @skb: the packet
1757 * @error: the error code
1758 * @gateway: CIPSO gateway flag
1759 *
1760 * Description:
1761 * Based on the error code given in @error, send an ICMP error message back to
1762 * the originating host. From the IETF draft ...
1763 *
1764 * "If the contents of the CIPSO [option] are valid but the security label is
1765 * outside of the configured host or port label range, the datagram is
1766 * discarded and an ICMP 'destination unreachable' (type 3) is generated and
1767 * returned. The code field of the ICMP is set to 'communication with
1768 * destination network administratively prohibited' (code 9) or to
1769 * 'communication with destination host administratively prohibited'
1770 * (code 10). The value of the code is dependent on whether the originator
1771 * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The
1772 * recipient of the ICMP message MUST be able to handle either value. The
1773 * same procedure is performed if a CIPSO [option] can not be added to an
1774 * IP packet because it is too large to fit in the IP options area."
1775 *
1776 * "If the error is triggered by receipt of an ICMP message, the message is
1777 * discarded and no response is permitted (consistent with general ICMP
1778 * processing rules)."
1779 *
1780 */
1781void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway)
1782{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001783 if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES)
Paul Moore446fda42006-08-03 16:48:06 -07001784 return;
1785
1786 if (gateway)
1787 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0);
1788 else
1789 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0);
1790}
1791
1792/**
Paul Moore948bf852008-10-10 10:16:32 -04001793 * cipso_v4_genopt - Generate a CIPSO option
1794 * @buf: the option buffer
1795 * @buf_len: the size of opt_buf
Paul Moore446fda42006-08-03 16:48:06 -07001796 * @doi_def: the CIPSO DOI to use
Paul Moore948bf852008-10-10 10:16:32 -04001797 * @secattr: the security attributes
Paul Moore446fda42006-08-03 16:48:06 -07001798 *
1799 * Description:
Paul Moore948bf852008-10-10 10:16:32 -04001800 * Generate a CIPSO option using the DOI definition and security attributes
1801 * passed to the function. Returns the length of the option on success and
1802 * negative values on failure.
Paul Moore446fda42006-08-03 16:48:06 -07001803 *
1804 */
Paul Moore948bf852008-10-10 10:16:32 -04001805static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
1806 const struct cipso_v4_doi *doi_def,
1807 const struct netlbl_lsm_secattr *secattr)
Paul Moore446fda42006-08-03 16:48:06 -07001808{
Paul Moore948bf852008-10-10 10:16:32 -04001809 int ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001810 u32 iter;
Paul Moore446fda42006-08-03 16:48:06 -07001811
Paul Moore948bf852008-10-10 10:16:32 -04001812 if (buf_len <= CIPSO_V4_HDR_LEN)
1813 return -ENOSPC;
Paul Moore91b1ed02006-11-17 17:38:49 -05001814
Paul Moore446fda42006-08-03 16:48:06 -07001815 /* XXX - This code assumes only one tag per CIPSO option which isn't
1816 * really a good assumption to make but since we only support the MAC
1817 * tags right now it is a safe assumption. */
1818 iter = 0;
1819 do {
Paul Moore91b1ed02006-11-17 17:38:49 -05001820 memset(buf, 0, buf_len);
Paul Moore446fda42006-08-03 16:48:06 -07001821 switch (doi_def->tags[iter]) {
1822 case CIPSO_V4_TAG_RBITMAP:
1823 ret_val = cipso_v4_gentag_rbm(doi_def,
Paul Moore91b1ed02006-11-17 17:38:49 -05001824 secattr,
1825 &buf[CIPSO_V4_HDR_LEN],
1826 buf_len - CIPSO_V4_HDR_LEN);
Paul Moore446fda42006-08-03 16:48:06 -07001827 break;
Paul Moore654bbc22006-11-29 13:18:19 -05001828 case CIPSO_V4_TAG_ENUM:
1829 ret_val = cipso_v4_gentag_enum(doi_def,
1830 secattr,
1831 &buf[CIPSO_V4_HDR_LEN],
1832 buf_len - CIPSO_V4_HDR_LEN);
1833 break;
Paul Moore484b3662006-11-29 13:18:20 -05001834 case CIPSO_V4_TAG_RANGE:
1835 ret_val = cipso_v4_gentag_rng(doi_def,
1836 secattr,
1837 &buf[CIPSO_V4_HDR_LEN],
1838 buf_len - CIPSO_V4_HDR_LEN);
1839 break;
Paul Moore15c45f72008-10-10 10:16:34 -04001840 case CIPSO_V4_TAG_LOCAL:
1841 ret_val = cipso_v4_gentag_loc(doi_def,
1842 secattr,
1843 &buf[CIPSO_V4_HDR_LEN],
1844 buf_len - CIPSO_V4_HDR_LEN);
1845 break;
Paul Moore446fda42006-08-03 16:48:06 -07001846 default:
Paul Moore948bf852008-10-10 10:16:32 -04001847 return -EPERM;
Paul Moore446fda42006-08-03 16:48:06 -07001848 }
1849
1850 iter++;
Paul Moore91b1ed02006-11-17 17:38:49 -05001851 } while (ret_val < 0 &&
Paul Moore446fda42006-08-03 16:48:06 -07001852 iter < CIPSO_V4_TAG_MAXCNT &&
1853 doi_def->tags[iter] != CIPSO_V4_TAG_INVALID);
Paul Moore91b1ed02006-11-17 17:38:49 -05001854 if (ret_val < 0)
Paul Moore948bf852008-10-10 10:16:32 -04001855 return ret_val;
Paul Moore91b1ed02006-11-17 17:38:49 -05001856 cipso_v4_gentag_hdr(doi_def, buf, ret_val);
Paul Moore948bf852008-10-10 10:16:32 -04001857 return CIPSO_V4_HDR_LEN + ret_val;
1858}
1859
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001860static void opt_kfree_rcu(struct rcu_head *head)
1861{
1862 kfree(container_of(head, struct ip_options_rcu, rcu));
1863}
1864
Paul Moore948bf852008-10-10 10:16:32 -04001865/**
1866 * cipso_v4_sock_setattr - Add a CIPSO option to a socket
1867 * @sk: the socket
1868 * @doi_def: the CIPSO DOI to use
1869 * @secattr: the specific security attributes of the socket
1870 *
1871 * Description:
1872 * Set the CIPSO option on the given socket using the DOI definition and
1873 * security attributes passed to the function. This function requires
1874 * exclusive access to @sk, which means it either needs to be in the
1875 * process of being created or locked. Returns zero on success and negative
1876 * values on failure.
1877 *
1878 */
1879int cipso_v4_sock_setattr(struct sock *sk,
1880 const struct cipso_v4_doi *doi_def,
1881 const struct netlbl_lsm_secattr *secattr)
1882{
1883 int ret_val = -EPERM;
1884 unsigned char *buf = NULL;
1885 u32 buf_len;
1886 u32 opt_len;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001887 struct ip_options_rcu *old, *opt = NULL;
Paul Moore948bf852008-10-10 10:16:32 -04001888 struct inet_sock *sk_inet;
1889 struct inet_connection_sock *sk_conn;
1890
1891 /* In the case of sock_create_lite(), the sock->sk field is not
1892 * defined yet but it is not a problem as the only users of these
1893 * "lite" PF_INET sockets are functions which do an accept() call
1894 * afterwards so we will label the socket as part of the accept(). */
1895 if (sk == NULL)
1896 return 0;
1897
1898 /* We allocate the maximum CIPSO option size here so we are probably
1899 * being a little wasteful, but it makes our life _much_ easier later
1900 * on and after all we are only talking about 40 bytes. */
1901 buf_len = CIPSO_V4_OPT_LEN_MAX;
1902 buf = kmalloc(buf_len, GFP_ATOMIC);
1903 if (buf == NULL) {
1904 ret_val = -ENOMEM;
1905 goto socket_setattr_failure;
1906 }
1907
1908 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
1909 if (ret_val < 0)
1910 goto socket_setattr_failure;
1911 buf_len = ret_val;
Paul Moore446fda42006-08-03 16:48:06 -07001912
1913 /* We can't use ip_options_get() directly because it makes a call to
1914 * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
Paul Mooref8687af2006-10-30 15:22:15 -08001915 * we won't always have CAP_NET_RAW even though we _always_ want to
1916 * set the IPOPT_CIPSO option. */
Paul Moore446fda42006-08-03 16:48:06 -07001917 opt_len = (buf_len + 3) & ~3;
1918 opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
1919 if (opt == NULL) {
1920 ret_val = -ENOMEM;
1921 goto socket_setattr_failure;
1922 }
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001923 memcpy(opt->opt.__data, buf, buf_len);
1924 opt->opt.optlen = opt_len;
1925 opt->opt.cipso = sizeof(struct iphdr);
Paul Moore446fda42006-08-03 16:48:06 -07001926 kfree(buf);
1927 buf = NULL;
Paul Moore446fda42006-08-03 16:48:06 -07001928
1929 sk_inet = inet_sk(sk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001930
1931 old = rcu_dereference_protected(sk_inet->inet_opt, sock_owned_by_user(sk));
Paul Moore446fda42006-08-03 16:48:06 -07001932 if (sk_inet->is_icsk) {
1933 sk_conn = inet_csk(sk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001934 if (old)
1935 sk_conn->icsk_ext_hdr_len -= old->opt.optlen;
1936 sk_conn->icsk_ext_hdr_len += opt->opt.optlen;
Paul Moore446fda42006-08-03 16:48:06 -07001937 sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
1938 }
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001939 rcu_assign_pointer(sk_inet->inet_opt, opt);
1940 if (old)
1941 call_rcu(&old->rcu, opt_kfree_rcu);
Paul Moore446fda42006-08-03 16:48:06 -07001942
1943 return 0;
1944
1945socket_setattr_failure:
1946 kfree(buf);
1947 kfree(opt);
1948 return ret_val;
1949}
1950
1951/**
Paul Moore389fb802009-03-27 17:10:34 -04001952 * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket
1953 * @req: the connection request socket
1954 * @doi_def: the CIPSO DOI to use
1955 * @secattr: the specific security attributes of the socket
Paul Moore014ab192008-10-10 10:16:33 -04001956 *
1957 * Description:
Paul Moore389fb802009-03-27 17:10:34 -04001958 * Set the CIPSO option on the given socket using the DOI definition and
1959 * security attributes passed to the function. Returns zero on success and
1960 * negative values on failure.
Paul Moore014ab192008-10-10 10:16:33 -04001961 *
1962 */
Paul Moore389fb802009-03-27 17:10:34 -04001963int cipso_v4_req_setattr(struct request_sock *req,
1964 const struct cipso_v4_doi *doi_def,
1965 const struct netlbl_lsm_secattr *secattr)
Paul Moore014ab192008-10-10 10:16:33 -04001966{
Paul Moore389fb802009-03-27 17:10:34 -04001967 int ret_val = -EPERM;
1968 unsigned char *buf = NULL;
1969 u32 buf_len;
1970 u32 opt_len;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001971 struct ip_options_rcu *opt = NULL;
Paul Moore389fb802009-03-27 17:10:34 -04001972 struct inet_request_sock *req_inet;
Paul Moore014ab192008-10-10 10:16:33 -04001973
Paul Moore389fb802009-03-27 17:10:34 -04001974 /* We allocate the maximum CIPSO option size here so we are probably
1975 * being a little wasteful, but it makes our life _much_ easier later
1976 * on and after all we are only talking about 40 bytes. */
1977 buf_len = CIPSO_V4_OPT_LEN_MAX;
1978 buf = kmalloc(buf_len, GFP_ATOMIC);
1979 if (buf == NULL) {
1980 ret_val = -ENOMEM;
1981 goto req_setattr_failure;
1982 }
1983
1984 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
1985 if (ret_val < 0)
1986 goto req_setattr_failure;
1987 buf_len = ret_val;
1988
1989 /* We can't use ip_options_get() directly because it makes a call to
1990 * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
1991 * we won't always have CAP_NET_RAW even though we _always_ want to
1992 * set the IPOPT_CIPSO option. */
1993 opt_len = (buf_len + 3) & ~3;
1994 opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
1995 if (opt == NULL) {
1996 ret_val = -ENOMEM;
1997 goto req_setattr_failure;
1998 }
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001999 memcpy(opt->opt.__data, buf, buf_len);
2000 opt->opt.optlen = opt_len;
2001 opt->opt.cipso = sizeof(struct iphdr);
Paul Moore389fb802009-03-27 17:10:34 -04002002 kfree(buf);
2003 buf = NULL;
2004
2005 req_inet = inet_rsk(req);
2006 opt = xchg(&req_inet->opt, opt);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002007 if (opt)
2008 call_rcu(&opt->rcu, opt_kfree_rcu);
Paul Moore389fb802009-03-27 17:10:34 -04002009
2010 return 0;
2011
2012req_setattr_failure:
2013 kfree(buf);
2014 kfree(opt);
2015 return ret_val;
2016}
2017
2018/**
2019 * cipso_v4_delopt - Delete the CIPSO option from a set of IP options
2020 * @opt_ptr: IP option pointer
2021 *
2022 * Description:
2023 * Deletes the CIPSO IP option from a set of IP options and makes the necessary
2024 * adjustments to the IP option structure. Returns zero on success, negative
2025 * values on failure.
2026 *
2027 */
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002028static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr)
Paul Moore389fb802009-03-27 17:10:34 -04002029{
2030 int hdr_delta = 0;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002031 struct ip_options_rcu *opt = *opt_ptr;
Paul Moore014ab192008-10-10 10:16:33 -04002032
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002033 if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) {
Paul Moore014ab192008-10-10 10:16:33 -04002034 u8 cipso_len;
2035 u8 cipso_off;
2036 unsigned char *cipso_ptr;
2037 int iter;
2038 int optlen_new;
2039
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002040 cipso_off = opt->opt.cipso - sizeof(struct iphdr);
2041 cipso_ptr = &opt->opt.__data[cipso_off];
Paul Moore014ab192008-10-10 10:16:33 -04002042 cipso_len = cipso_ptr[1];
2043
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002044 if (opt->opt.srr > opt->opt.cipso)
2045 opt->opt.srr -= cipso_len;
2046 if (opt->opt.rr > opt->opt.cipso)
2047 opt->opt.rr -= cipso_len;
2048 if (opt->opt.ts > opt->opt.cipso)
2049 opt->opt.ts -= cipso_len;
2050 if (opt->opt.router_alert > opt->opt.cipso)
2051 opt->opt.router_alert -= cipso_len;
2052 opt->opt.cipso = 0;
Paul Moore014ab192008-10-10 10:16:33 -04002053
2054 memmove(cipso_ptr, cipso_ptr + cipso_len,
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002055 opt->opt.optlen - cipso_off - cipso_len);
Paul Moore014ab192008-10-10 10:16:33 -04002056
2057 /* determining the new total option length is tricky because of
2058 * the padding necessary, the only thing i can think to do at
2059 * this point is walk the options one-by-one, skipping the
2060 * padding at the end to determine the actual option size and
2061 * from there we can determine the new total option length */
2062 iter = 0;
2063 optlen_new = 0;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002064 while (iter < opt->opt.optlen)
2065 if (opt->opt.__data[iter] != IPOPT_NOP) {
2066 iter += opt->opt.__data[iter + 1];
Paul Moore014ab192008-10-10 10:16:33 -04002067 optlen_new = iter;
2068 } else
2069 iter++;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002070 hdr_delta = opt->opt.optlen;
2071 opt->opt.optlen = (optlen_new + 3) & ~3;
2072 hdr_delta -= opt->opt.optlen;
Paul Moore014ab192008-10-10 10:16:33 -04002073 } else {
2074 /* only the cipso option was present on the socket so we can
2075 * remove the entire option struct */
Paul Moore389fb802009-03-27 17:10:34 -04002076 *opt_ptr = NULL;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002077 hdr_delta = opt->opt.optlen;
2078 call_rcu(&opt->rcu, opt_kfree_rcu);
Paul Moore014ab192008-10-10 10:16:33 -04002079 }
2080
Paul Moore389fb802009-03-27 17:10:34 -04002081 return hdr_delta;
2082}
2083
2084/**
2085 * cipso_v4_sock_delattr - Delete the CIPSO option from a socket
2086 * @sk: the socket
2087 *
2088 * Description:
2089 * Removes the CIPSO option from a socket, if present.
2090 *
2091 */
2092void cipso_v4_sock_delattr(struct sock *sk)
2093{
2094 int hdr_delta;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002095 struct ip_options_rcu *opt;
Paul Moore389fb802009-03-27 17:10:34 -04002096 struct inet_sock *sk_inet;
2097
2098 sk_inet = inet_sk(sk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002099 opt = rcu_dereference_protected(sk_inet->inet_opt, 1);
2100 if (opt == NULL || opt->opt.cipso == 0)
Paul Moore389fb802009-03-27 17:10:34 -04002101 return;
2102
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002103 hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt);
Paul Moore014ab192008-10-10 10:16:33 -04002104 if (sk_inet->is_icsk && hdr_delta > 0) {
2105 struct inet_connection_sock *sk_conn = inet_csk(sk);
2106 sk_conn->icsk_ext_hdr_len -= hdr_delta;
2107 sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
2108 }
2109}
2110
2111/**
Paul Moore389fb802009-03-27 17:10:34 -04002112 * cipso_v4_req_delattr - Delete the CIPSO option from a request socket
2113 * @reg: the request socket
2114 *
2115 * Description:
2116 * Removes the CIPSO option from a request socket, if present.
2117 *
2118 */
2119void cipso_v4_req_delattr(struct request_sock *req)
2120{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002121 struct ip_options_rcu *opt;
Paul Moore389fb802009-03-27 17:10:34 -04002122 struct inet_request_sock *req_inet;
2123
2124 req_inet = inet_rsk(req);
2125 opt = req_inet->opt;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002126 if (opt == NULL || opt->opt.cipso == 0)
Paul Moore389fb802009-03-27 17:10:34 -04002127 return;
2128
2129 cipso_v4_delopt(&req_inet->opt);
2130}
2131
2132/**
Paul Moore63d804ea2007-09-15 21:45:13 -07002133 * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions
2134 * @cipso: the CIPSO v4 option
2135 * @secattr: the security attributes
2136 *
2137 * Description:
2138 * Inspect @cipso and return the security attributes in @secattr. Returns zero
2139 * on success and negative values on failure.
2140 *
2141 */
2142static int cipso_v4_getattr(const unsigned char *cipso,
2143 struct netlbl_lsm_secattr *secattr)
2144{
2145 int ret_val = -ENOMSG;
2146 u32 doi;
2147 struct cipso_v4_doi *doi_def;
2148
2149 if (cipso_v4_cache_check(cipso, cipso[1], secattr) == 0)
2150 return 0;
2151
Harvey Harrisond3e2ce32008-05-02 16:26:16 -07002152 doi = get_unaligned_be32(&cipso[2]);
Paul Moore63d804ea2007-09-15 21:45:13 -07002153 rcu_read_lock();
2154 doi_def = cipso_v4_doi_search(doi);
2155 if (doi_def == NULL)
2156 goto getattr_return;
2157 /* XXX - This code assumes only one tag per CIPSO option which isn't
2158 * really a good assumption to make but since we only support the MAC
2159 * tags right now it is a safe assumption. */
2160 switch (cipso[6]) {
2161 case CIPSO_V4_TAG_RBITMAP:
2162 ret_val = cipso_v4_parsetag_rbm(doi_def, &cipso[6], secattr);
2163 break;
2164 case CIPSO_V4_TAG_ENUM:
2165 ret_val = cipso_v4_parsetag_enum(doi_def, &cipso[6], secattr);
2166 break;
2167 case CIPSO_V4_TAG_RANGE:
2168 ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr);
2169 break;
Paul Moore15c45f72008-10-10 10:16:34 -04002170 case CIPSO_V4_TAG_LOCAL:
2171 ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr);
2172 break;
Paul Moore63d804ea2007-09-15 21:45:13 -07002173 }
Paul Moore16efd452008-01-29 08:37:59 -05002174 if (ret_val == 0)
2175 secattr->type = NETLBL_NLTYPE_CIPSOV4;
Paul Moore63d804ea2007-09-15 21:45:13 -07002176
2177getattr_return:
2178 rcu_read_unlock();
2179 return ret_val;
2180}
2181
2182/**
Paul Moore14a72f52006-09-25 15:52:01 -07002183 * cipso_v4_sock_getattr - Get the security attributes from a sock
2184 * @sk: the sock
2185 * @secattr: the security attributes
2186 *
2187 * Description:
2188 * Query @sk to see if there is a CIPSO option attached to the sock and if
2189 * there is return the CIPSO security attributes in @secattr. This function
2190 * requires that @sk be locked, or privately held, but it does not do any
2191 * locking itself. Returns zero on success and negative values on failure.
2192 *
2193 */
2194int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
2195{
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002196 struct ip_options_rcu *opt;
2197 int res = -ENOMSG;
Paul Moore14a72f52006-09-25 15:52:01 -07002198
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00002199 rcu_read_lock();
2200 opt = rcu_dereference(inet_sk(sk)->inet_opt);
2201 if (opt && opt->opt.cipso)
2202 res = cipso_v4_getattr(opt->opt.__data +
2203 opt->opt.cipso -
2204 sizeof(struct iphdr),
2205 secattr);
2206 rcu_read_unlock();
2207 return res;
Paul Moore14a72f52006-09-25 15:52:01 -07002208}
2209
2210/**
Paul Moore948bf852008-10-10 10:16:32 -04002211 * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet
2212 * @skb: the packet
2213 * @secattr: the security attributes
2214 *
2215 * Description:
2216 * Set the CIPSO option on the given packet based on the security attributes.
2217 * Returns a pointer to the IP header on success and NULL on failure.
2218 *
2219 */
2220int cipso_v4_skbuff_setattr(struct sk_buff *skb,
2221 const struct cipso_v4_doi *doi_def,
2222 const struct netlbl_lsm_secattr *secattr)
2223{
2224 int ret_val;
2225 struct iphdr *iph;
2226 struct ip_options *opt = &IPCB(skb)->opt;
2227 unsigned char buf[CIPSO_V4_OPT_LEN_MAX];
2228 u32 buf_len = CIPSO_V4_OPT_LEN_MAX;
2229 u32 opt_len;
2230 int len_delta;
2231
roel kluin00af5c62008-10-29 15:55:53 -04002232 ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
2233 if (ret_val < 0)
2234 return ret_val;
2235 buf_len = ret_val;
Paul Moore948bf852008-10-10 10:16:32 -04002236 opt_len = (buf_len + 3) & ~3;
2237
2238 /* we overwrite any existing options to ensure that we have enough
2239 * room for the CIPSO option, the reason is that we _need_ to guarantee
2240 * that the security label is applied to the packet - we do the same
2241 * thing when using the socket options and it hasn't caused a problem,
2242 * if we need to we can always revisit this choice later */
2243
2244 len_delta = opt_len - opt->optlen;
2245 /* if we don't ensure enough headroom we could panic on the skb_push()
2246 * call below so make sure we have enough, we are also "mangling" the
2247 * packet so we should probably do a copy-on-write call anyway */
2248 ret_val = skb_cow(skb, skb_headroom(skb) + len_delta);
2249 if (ret_val < 0)
2250 return ret_val;
2251
2252 if (len_delta > 0) {
2253 /* we assume that the header + opt->optlen have already been
2254 * "pushed" in ip_options_build() or similar */
2255 iph = ip_hdr(skb);
2256 skb_push(skb, len_delta);
2257 memmove((char *)iph - len_delta, iph, iph->ihl << 2);
2258 skb_reset_network_header(skb);
2259 iph = ip_hdr(skb);
2260 } else if (len_delta < 0) {
2261 iph = ip_hdr(skb);
2262 memset(iph + 1, IPOPT_NOP, opt->optlen);
2263 } else
2264 iph = ip_hdr(skb);
2265
2266 if (opt->optlen > 0)
2267 memset(opt, 0, sizeof(*opt));
2268 opt->optlen = opt_len;
2269 opt->cipso = sizeof(struct iphdr);
2270 opt->is_changed = 1;
2271
2272 /* we have to do the following because we are being called from a
2273 * netfilter hook which means the packet already has had the header
2274 * fields populated and the checksum calculated - yes this means we
2275 * are doing more work than needed but we do it to keep the core
2276 * stack clean and tidy */
2277 memcpy(iph + 1, buf, buf_len);
2278 if (opt_len > buf_len)
2279 memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len);
2280 if (len_delta != 0) {
2281 iph->ihl = 5 + (opt_len >> 2);
2282 iph->tot_len = htons(skb->len);
2283 }
2284 ip_send_check(iph);
2285
2286 return 0;
2287}
2288
2289/**
2290 * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet
2291 * @skb: the packet
2292 *
2293 * Description:
2294 * Removes any and all CIPSO options from the given packet. Returns zero on
2295 * success, negative values on failure.
2296 *
2297 */
2298int cipso_v4_skbuff_delattr(struct sk_buff *skb)
2299{
2300 int ret_val;
2301 struct iphdr *iph;
2302 struct ip_options *opt = &IPCB(skb)->opt;
2303 unsigned char *cipso_ptr;
2304
2305 if (opt->cipso == 0)
2306 return 0;
2307
2308 /* since we are changing the packet we should make a copy */
2309 ret_val = skb_cow(skb, skb_headroom(skb));
2310 if (ret_val < 0)
2311 return ret_val;
2312
2313 /* the easiest thing to do is just replace the cipso option with noop
2314 * options since we don't change the size of the packet, although we
2315 * still need to recalculate the checksum */
2316
2317 iph = ip_hdr(skb);
2318 cipso_ptr = (unsigned char *)iph + opt->cipso;
2319 memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]);
2320 opt->cipso = 0;
2321 opt->is_changed = 1;
2322
2323 ip_send_check(iph);
2324
2325 return 0;
2326}
2327
2328/**
Paul Moore446fda42006-08-03 16:48:06 -07002329 * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option
2330 * @skb: the packet
2331 * @secattr: the security attributes
2332 *
2333 * Description:
2334 * Parse the given packet's CIPSO option and return the security attributes.
2335 * Returns zero on success and negative values on failure.
2336 *
2337 */
2338int cipso_v4_skbuff_getattr(const struct sk_buff *skb,
2339 struct netlbl_lsm_secattr *secattr)
2340{
Paul Moore63d804ea2007-09-15 21:45:13 -07002341 return cipso_v4_getattr(CIPSO_V4_OPTPTR(skb), secattr);
Paul Moore446fda42006-08-03 16:48:06 -07002342}
2343
2344/*
2345 * Setup Functions
2346 */
2347
2348/**
2349 * cipso_v4_init - Initialize the CIPSO module
2350 *
2351 * Description:
2352 * Initialize the CIPSO module and prepare it for use. Returns zero on success
2353 * and negative values on failure.
2354 *
2355 */
2356static int __init cipso_v4_init(void)
2357{
2358 int ret_val;
2359
2360 ret_val = cipso_v4_cache_init();
2361 if (ret_val != 0)
2362 panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n",
2363 ret_val);
2364
2365 return 0;
2366}
2367
2368subsys_initcall(cipso_v4_init);