Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1 | /* |
| 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 |
| 6 | * FIPS-188, copies of both documents can be found in the Documentation |
| 7 | * directory. While CIPSO never became a full IETF RFC standard many vendors |
| 8 | * have chosen to adopt the protocol and over the years it has become a |
| 9 | * de-facto standard for labeled networking. |
| 10 | * |
| 11 | * Author: Paul Moore <paul.moore@hp.com> |
| 12 | * |
| 13 | */ |
| 14 | |
| 15 | /* |
| 16 | * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 |
| 17 | * |
| 18 | * This program is free software; you can redistribute it and/or modify |
| 19 | * it under the terms of the GNU General Public License as published by |
| 20 | * the Free Software Foundation; either version 2 of the License, or |
| 21 | * (at your option) any later version. |
| 22 | * |
| 23 | * This program is distributed in the hope that it will be useful, |
| 24 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 25 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 26 | * the GNU General Public License for more details. |
| 27 | * |
| 28 | * You should have received a copy of the GNU General Public License |
| 29 | * along with this program; if not, write to the Free Software |
| 30 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 31 | * |
| 32 | */ |
| 33 | |
| 34 | #include <linux/init.h> |
| 35 | #include <linux/types.h> |
| 36 | #include <linux/rcupdate.h> |
| 37 | #include <linux/list.h> |
| 38 | #include <linux/spinlock.h> |
| 39 | #include <linux/string.h> |
| 40 | #include <linux/jhash.h> |
| 41 | #include <net/ip.h> |
| 42 | #include <net/icmp.h> |
| 43 | #include <net/tcp.h> |
| 44 | #include <net/netlabel.h> |
| 45 | #include <net/cipso_ipv4.h> |
paul.moore@hp.com | ffb733c | 2006-10-04 11:46:31 -0400 | [diff] [blame] | 46 | #include <asm/atomic.h> |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 47 | #include <asm/bug.h> |
| 48 | |
| 49 | struct cipso_v4_domhsh_entry { |
| 50 | char *domain; |
| 51 | u32 valid; |
| 52 | struct list_head list; |
| 53 | struct rcu_head rcu; |
| 54 | }; |
| 55 | |
| 56 | /* List of available DOI definitions */ |
| 57 | /* XXX - Updates should be minimal so having a single lock for the |
| 58 | * cipso_v4_doi_list and the cipso_v4_doi_list->dom_list should be |
| 59 | * okay. */ |
| 60 | /* XXX - This currently assumes a minimal number of different DOIs in use, |
| 61 | * if in practice there are a lot of different DOIs this list should |
| 62 | * probably be turned into a hash table or something similar so we |
| 63 | * can do quick lookups. */ |
Adrian Bunk | 8ce11e6 | 2006-08-07 21:50:48 -0700 | [diff] [blame] | 64 | static DEFINE_SPINLOCK(cipso_v4_doi_list_lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 65 | static struct list_head cipso_v4_doi_list = LIST_HEAD_INIT(cipso_v4_doi_list); |
| 66 | |
| 67 | /* Label mapping cache */ |
| 68 | int cipso_v4_cache_enabled = 1; |
| 69 | int cipso_v4_cache_bucketsize = 10; |
| 70 | #define CIPSO_V4_CACHE_BUCKETBITS 7 |
| 71 | #define CIPSO_V4_CACHE_BUCKETS (1 << CIPSO_V4_CACHE_BUCKETBITS) |
| 72 | #define CIPSO_V4_CACHE_REORDERLIMIT 10 |
| 73 | struct cipso_v4_map_cache_bkt { |
| 74 | spinlock_t lock; |
| 75 | u32 size; |
| 76 | struct list_head list; |
| 77 | }; |
| 78 | struct cipso_v4_map_cache_entry { |
| 79 | u32 hash; |
| 80 | unsigned char *key; |
| 81 | size_t key_len; |
| 82 | |
paul.moore@hp.com | ffb733c | 2006-10-04 11:46:31 -0400 | [diff] [blame] | 83 | struct netlbl_lsm_cache *lsm_data; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 84 | |
| 85 | u32 activity; |
| 86 | struct list_head list; |
| 87 | }; |
| 88 | static struct cipso_v4_map_cache_bkt *cipso_v4_cache = NULL; |
| 89 | |
| 90 | /* Restricted bitmap (tag #1) flags */ |
| 91 | int cipso_v4_rbm_optfmt = 0; |
| 92 | int cipso_v4_rbm_strictvalid = 1; |
| 93 | |
| 94 | /* |
| 95 | * Helper Functions |
| 96 | */ |
| 97 | |
| 98 | /** |
| 99 | * cipso_v4_bitmap_walk - Walk a bitmap looking for a bit |
| 100 | * @bitmap: the bitmap |
| 101 | * @bitmap_len: length in bits |
| 102 | * @offset: starting offset |
| 103 | * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit |
| 104 | * |
| 105 | * Description: |
| 106 | * Starting at @offset, walk the bitmap from left to right until either the |
| 107 | * desired bit is found or we reach the end. Return the bit offset, -1 if |
| 108 | * not found, or -2 if error. |
| 109 | */ |
| 110 | static int cipso_v4_bitmap_walk(const unsigned char *bitmap, |
| 111 | u32 bitmap_len, |
| 112 | u32 offset, |
| 113 | u8 state) |
| 114 | { |
| 115 | u32 bit_spot; |
| 116 | u32 byte_offset; |
| 117 | unsigned char bitmask; |
| 118 | unsigned char byte; |
| 119 | |
| 120 | /* gcc always rounds to zero when doing integer division */ |
| 121 | byte_offset = offset / 8; |
| 122 | byte = bitmap[byte_offset]; |
| 123 | bit_spot = offset; |
| 124 | bitmask = 0x80 >> (offset % 8); |
| 125 | |
| 126 | while (bit_spot < bitmap_len) { |
| 127 | if ((state && (byte & bitmask) == bitmask) || |
| 128 | (state == 0 && (byte & bitmask) == 0)) |
| 129 | return bit_spot; |
| 130 | |
| 131 | bit_spot++; |
| 132 | bitmask >>= 1; |
| 133 | if (bitmask == 0) { |
| 134 | byte = bitmap[++byte_offset]; |
| 135 | bitmask = 0x80; |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | return -1; |
| 140 | } |
| 141 | |
| 142 | /** |
| 143 | * cipso_v4_bitmap_setbit - Sets a single bit in a bitmap |
| 144 | * @bitmap: the bitmap |
| 145 | * @bit: the bit |
| 146 | * @state: if non-zero, set the bit (1) else clear the bit (0) |
| 147 | * |
| 148 | * Description: |
| 149 | * Set a single bit in the bitmask. Returns zero on success, negative values |
| 150 | * on error. |
| 151 | */ |
| 152 | static void cipso_v4_bitmap_setbit(unsigned char *bitmap, |
| 153 | u32 bit, |
| 154 | u8 state) |
| 155 | { |
| 156 | u32 byte_spot; |
| 157 | u8 bitmask; |
| 158 | |
| 159 | /* gcc always rounds to zero when doing integer division */ |
| 160 | byte_spot = bit / 8; |
| 161 | bitmask = 0x80 >> (bit % 8); |
| 162 | if (state) |
| 163 | bitmap[byte_spot] |= bitmask; |
| 164 | else |
| 165 | bitmap[byte_spot] &= ~bitmask; |
| 166 | } |
| 167 | |
| 168 | /** |
| 169 | * cipso_v4_doi_domhsh_free - Frees a domain list entry |
| 170 | * @entry: the entry's RCU field |
| 171 | * |
| 172 | * Description: |
| 173 | * This function is designed to be used as a callback to the call_rcu() |
| 174 | * function so that the memory allocated to a domain list entry can be released |
| 175 | * safely. |
| 176 | * |
| 177 | */ |
| 178 | static void cipso_v4_doi_domhsh_free(struct rcu_head *entry) |
| 179 | { |
| 180 | struct cipso_v4_domhsh_entry *ptr; |
| 181 | |
| 182 | ptr = container_of(entry, struct cipso_v4_domhsh_entry, rcu); |
| 183 | kfree(ptr->domain); |
| 184 | kfree(ptr); |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * cipso_v4_cache_entry_free - Frees a cache entry |
| 189 | * @entry: the entry to free |
| 190 | * |
| 191 | * Description: |
paul.moore@hp.com | ffb733c | 2006-10-04 11:46:31 -0400 | [diff] [blame] | 192 | * This function frees the memory associated with a cache entry including the |
| 193 | * LSM cache data if there are no longer any users, i.e. reference count == 0. |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 194 | * |
| 195 | */ |
| 196 | static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) |
| 197 | { |
paul.moore@hp.com | ffb733c | 2006-10-04 11:46:31 -0400 | [diff] [blame] | 198 | if (entry->lsm_data) |
| 199 | netlbl_secattr_cache_free(entry->lsm_data); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 200 | kfree(entry->key); |
| 201 | kfree(entry); |
| 202 | } |
| 203 | |
| 204 | /** |
| 205 | * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache |
| 206 | * @key: the hash key |
| 207 | * @key_len: the length of the key in bytes |
| 208 | * |
| 209 | * Description: |
| 210 | * The CIPSO tag hashing function. Returns a 32-bit hash value. |
| 211 | * |
| 212 | */ |
| 213 | static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) |
| 214 | { |
| 215 | return jhash(key, key_len, 0); |
| 216 | } |
| 217 | |
| 218 | /* |
| 219 | * Label Mapping Cache Functions |
| 220 | */ |
| 221 | |
| 222 | /** |
| 223 | * cipso_v4_cache_init - Initialize the CIPSO cache |
| 224 | * |
| 225 | * Description: |
| 226 | * Initializes the CIPSO label mapping cache, this function should be called |
| 227 | * before any of the other functions defined in this file. Returns zero on |
| 228 | * success, negative values on error. |
| 229 | * |
| 230 | */ |
| 231 | static int cipso_v4_cache_init(void) |
| 232 | { |
| 233 | u32 iter; |
| 234 | |
| 235 | cipso_v4_cache = kcalloc(CIPSO_V4_CACHE_BUCKETS, |
| 236 | sizeof(struct cipso_v4_map_cache_bkt), |
| 237 | GFP_KERNEL); |
| 238 | if (cipso_v4_cache == NULL) |
| 239 | return -ENOMEM; |
| 240 | |
| 241 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { |
| 242 | spin_lock_init(&cipso_v4_cache[iter].lock); |
| 243 | cipso_v4_cache[iter].size = 0; |
| 244 | INIT_LIST_HEAD(&cipso_v4_cache[iter].list); |
| 245 | } |
| 246 | |
| 247 | return 0; |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache |
| 252 | * |
| 253 | * Description: |
| 254 | * Invalidates and frees any entries in the CIPSO cache. Returns zero on |
| 255 | * success and negative values on failure. |
| 256 | * |
| 257 | */ |
| 258 | void cipso_v4_cache_invalidate(void) |
| 259 | { |
| 260 | struct cipso_v4_map_cache_entry *entry, *tmp_entry; |
| 261 | u32 iter; |
| 262 | |
| 263 | for (iter = 0; iter < CIPSO_V4_CACHE_BUCKETS; iter++) { |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 264 | spin_lock_bh(&cipso_v4_cache[iter].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 265 | list_for_each_entry_safe(entry, |
| 266 | tmp_entry, |
| 267 | &cipso_v4_cache[iter].list, list) { |
| 268 | list_del(&entry->list); |
| 269 | cipso_v4_cache_entry_free(entry); |
| 270 | } |
| 271 | cipso_v4_cache[iter].size = 0; |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 272 | spin_unlock_bh(&cipso_v4_cache[iter].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 273 | } |
| 274 | |
| 275 | return; |
| 276 | } |
| 277 | |
| 278 | /** |
| 279 | * cipso_v4_cache_check - Check the CIPSO cache for a label mapping |
| 280 | * @key: the buffer to check |
| 281 | * @key_len: buffer length in bytes |
| 282 | * @secattr: the security attribute struct to use |
| 283 | * |
| 284 | * Description: |
| 285 | * This function checks the cache to see if a label mapping already exists for |
| 286 | * the given key. If there is a match then the cache is adjusted and the |
| 287 | * @secattr struct is populated with the correct LSM security attributes. The |
| 288 | * cache is adjusted in the following manner if the entry is not already the |
| 289 | * first in the cache bucket: |
| 290 | * |
| 291 | * 1. The cache entry's activity counter is incremented |
| 292 | * 2. The previous (higher ranking) entry's activity counter is decremented |
| 293 | * 3. If the difference between the two activity counters is geater than |
| 294 | * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped |
| 295 | * |
| 296 | * Returns zero on success, -ENOENT for a cache miss, and other negative values |
| 297 | * on error. |
| 298 | * |
| 299 | */ |
| 300 | static int cipso_v4_cache_check(const unsigned char *key, |
| 301 | u32 key_len, |
| 302 | struct netlbl_lsm_secattr *secattr) |
| 303 | { |
| 304 | u32 bkt; |
| 305 | struct cipso_v4_map_cache_entry *entry; |
| 306 | struct cipso_v4_map_cache_entry *prev_entry = NULL; |
| 307 | u32 hash; |
| 308 | |
| 309 | if (!cipso_v4_cache_enabled) |
| 310 | return -ENOENT; |
| 311 | |
| 312 | hash = cipso_v4_map_cache_hash(key, key_len); |
| 313 | bkt = hash & (CIPSO_V4_CACHE_BUCKETBITS - 1); |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 314 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 315 | list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) { |
| 316 | if (entry->hash == hash && |
| 317 | entry->key_len == key_len && |
| 318 | memcmp(entry->key, key, key_len) == 0) { |
| 319 | entry->activity += 1; |
paul.moore@hp.com | ffb733c | 2006-10-04 11:46:31 -0400 | [diff] [blame] | 320 | atomic_inc(&entry->lsm_data->refcount); |
| 321 | secattr->cache = entry->lsm_data; |
Paul Moore | 701a90b | 2006-11-17 17:38:46 -0500 | [diff] [blame] | 322 | secattr->flags |= NETLBL_SECATTR_CACHE; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 323 | if (prev_entry == NULL) { |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 324 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 325 | return 0; |
| 326 | } |
| 327 | |
| 328 | if (prev_entry->activity > 0) |
| 329 | prev_entry->activity -= 1; |
| 330 | if (entry->activity > prev_entry->activity && |
| 331 | entry->activity - prev_entry->activity > |
| 332 | CIPSO_V4_CACHE_REORDERLIMIT) { |
| 333 | __list_del(entry->list.prev, entry->list.next); |
| 334 | __list_add(&entry->list, |
| 335 | prev_entry->list.prev, |
| 336 | &prev_entry->list); |
| 337 | } |
| 338 | |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 339 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 340 | return 0; |
| 341 | } |
| 342 | prev_entry = entry; |
| 343 | } |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 344 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 345 | |
| 346 | return -ENOENT; |
| 347 | } |
| 348 | |
| 349 | /** |
| 350 | * cipso_v4_cache_add - Add an entry to the CIPSO cache |
| 351 | * @skb: the packet |
| 352 | * @secattr: the packet's security attributes |
| 353 | * |
| 354 | * Description: |
| 355 | * Add a new entry into the CIPSO label mapping cache. Add the new entry to |
| 356 | * head of the cache bucket's list, if the cache bucket is out of room remove |
| 357 | * the last entry in the list first. It is important to note that there is |
| 358 | * currently no checking for duplicate keys. Returns zero on success, |
| 359 | * negative values on failure. |
| 360 | * |
| 361 | */ |
| 362 | int cipso_v4_cache_add(const struct sk_buff *skb, |
| 363 | const struct netlbl_lsm_secattr *secattr) |
| 364 | { |
| 365 | int ret_val = -EPERM; |
| 366 | u32 bkt; |
| 367 | struct cipso_v4_map_cache_entry *entry = NULL; |
| 368 | struct cipso_v4_map_cache_entry *old_entry = NULL; |
| 369 | unsigned char *cipso_ptr; |
| 370 | u32 cipso_ptr_len; |
| 371 | |
| 372 | if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) |
| 373 | return 0; |
| 374 | |
| 375 | cipso_ptr = CIPSO_V4_OPTPTR(skb); |
| 376 | cipso_ptr_len = cipso_ptr[1]; |
| 377 | |
| 378 | entry = kzalloc(sizeof(*entry), GFP_ATOMIC); |
| 379 | if (entry == NULL) |
| 380 | return -ENOMEM; |
Arnaldo Carvalho de Melo | fac5d73 | 2006-11-17 11:14:16 -0200 | [diff] [blame] | 381 | entry->key = kmemdup(cipso_ptr, cipso_ptr_len, GFP_ATOMIC); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 382 | if (entry->key == NULL) { |
| 383 | ret_val = -ENOMEM; |
| 384 | goto cache_add_failure; |
| 385 | } |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 386 | entry->key_len = cipso_ptr_len; |
| 387 | entry->hash = cipso_v4_map_cache_hash(cipso_ptr, cipso_ptr_len); |
paul.moore@hp.com | ffb733c | 2006-10-04 11:46:31 -0400 | [diff] [blame] | 388 | atomic_inc(&secattr->cache->refcount); |
| 389 | entry->lsm_data = secattr->cache; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 390 | |
| 391 | bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETBITS - 1); |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 392 | spin_lock_bh(&cipso_v4_cache[bkt].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 393 | if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { |
| 394 | list_add(&entry->list, &cipso_v4_cache[bkt].list); |
| 395 | cipso_v4_cache[bkt].size += 1; |
| 396 | } else { |
| 397 | old_entry = list_entry(cipso_v4_cache[bkt].list.prev, |
| 398 | struct cipso_v4_map_cache_entry, list); |
| 399 | list_del(&old_entry->list); |
| 400 | list_add(&entry->list, &cipso_v4_cache[bkt].list); |
| 401 | cipso_v4_cache_entry_free(old_entry); |
| 402 | } |
Paul Moore | 609c92f | 2006-09-25 15:52:37 -0700 | [diff] [blame] | 403 | spin_unlock_bh(&cipso_v4_cache[bkt].lock); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 404 | |
| 405 | return 0; |
| 406 | |
| 407 | cache_add_failure: |
| 408 | if (entry) |
| 409 | cipso_v4_cache_entry_free(entry); |
| 410 | return ret_val; |
| 411 | } |
| 412 | |
| 413 | /* |
| 414 | * DOI List Functions |
| 415 | */ |
| 416 | |
| 417 | /** |
| 418 | * cipso_v4_doi_search - Searches for a DOI definition |
| 419 | * @doi: the DOI to search for |
| 420 | * |
| 421 | * Description: |
| 422 | * Search the DOI definition list for a DOI definition with a DOI value that |
| 423 | * matches @doi. The caller is responsibile for calling rcu_read_[un]lock(). |
| 424 | * Returns a pointer to the DOI definition on success and NULL on failure. |
| 425 | */ |
| 426 | static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) |
| 427 | { |
| 428 | struct cipso_v4_doi *iter; |
| 429 | |
| 430 | list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) |
| 431 | if (iter->doi == doi && iter->valid) |
| 432 | return iter; |
| 433 | return NULL; |
| 434 | } |
| 435 | |
| 436 | /** |
| 437 | * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine |
| 438 | * @doi_def: the DOI structure |
| 439 | * |
| 440 | * Description: |
| 441 | * The caller defines a new DOI for use by the CIPSO engine and calls this |
| 442 | * function to add it to the list of acceptable domains. The caller must |
| 443 | * ensure that the mapping table specified in @doi_def->map meets all of the |
| 444 | * requirements of the mapping type (see cipso_ipv4.h for details). Returns |
| 445 | * zero on success and non-zero on failure. |
| 446 | * |
| 447 | */ |
| 448 | int cipso_v4_doi_add(struct cipso_v4_doi *doi_def) |
| 449 | { |
Paul Moore | 6ce61a7 | 2006-11-17 17:38:48 -0500 | [diff] [blame] | 450 | u32 iter; |
| 451 | |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 452 | if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN) |
| 453 | return -EINVAL; |
Paul Moore | 6ce61a7 | 2006-11-17 17:38:48 -0500 | [diff] [blame] | 454 | for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) { |
| 455 | switch (doi_def->tags[iter]) { |
| 456 | case CIPSO_V4_TAG_RBITMAP: |
| 457 | break; |
| 458 | case CIPSO_V4_TAG_INVALID: |
| 459 | if (iter == 0) |
| 460 | return -EINVAL; |
| 461 | break; |
| 462 | default: |
| 463 | return -EINVAL; |
| 464 | } |
| 465 | } |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 466 | |
| 467 | doi_def->valid = 1; |
| 468 | INIT_RCU_HEAD(&doi_def->rcu); |
| 469 | INIT_LIST_HEAD(&doi_def->dom_list); |
| 470 | |
| 471 | rcu_read_lock(); |
| 472 | if (cipso_v4_doi_search(doi_def->doi) != NULL) |
| 473 | goto doi_add_failure_rlock; |
| 474 | spin_lock(&cipso_v4_doi_list_lock); |
| 475 | if (cipso_v4_doi_search(doi_def->doi) != NULL) |
| 476 | goto doi_add_failure_slock; |
| 477 | list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list); |
| 478 | spin_unlock(&cipso_v4_doi_list_lock); |
| 479 | rcu_read_unlock(); |
| 480 | |
| 481 | return 0; |
| 482 | |
| 483 | doi_add_failure_slock: |
| 484 | spin_unlock(&cipso_v4_doi_list_lock); |
| 485 | doi_add_failure_rlock: |
| 486 | rcu_read_unlock(); |
| 487 | return -EEXIST; |
| 488 | } |
| 489 | |
| 490 | /** |
| 491 | * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine |
| 492 | * @doi: the DOI value |
Paul Moore | 32f50cd | 2006-09-28 14:51:47 -0700 | [diff] [blame] | 493 | * @audit_secid: the LSM secid to use in the audit message |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 494 | * @callback: the DOI cleanup/free callback |
| 495 | * |
| 496 | * Description: |
| 497 | * Removes a DOI definition from the CIPSO engine, @callback is called to |
| 498 | * free any memory. The NetLabel routines will be called to release their own |
| 499 | * LSM domain mappings as well as our own domain list. Returns zero on |
| 500 | * success and negative values on failure. |
| 501 | * |
| 502 | */ |
Paul Moore | 32f50cd | 2006-09-28 14:51:47 -0700 | [diff] [blame] | 503 | int cipso_v4_doi_remove(u32 doi, |
Paul Moore | 95d4e6b | 2006-09-29 17:05:05 -0700 | [diff] [blame] | 504 | struct netlbl_audit *audit_info, |
Paul Moore | 32f50cd | 2006-09-28 14:51:47 -0700 | [diff] [blame] | 505 | void (*callback) (struct rcu_head * head)) |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 506 | { |
| 507 | struct cipso_v4_doi *doi_def; |
| 508 | struct cipso_v4_domhsh_entry *dom_iter; |
| 509 | |
| 510 | rcu_read_lock(); |
| 511 | if (cipso_v4_doi_search(doi) != NULL) { |
| 512 | spin_lock(&cipso_v4_doi_list_lock); |
| 513 | doi_def = cipso_v4_doi_search(doi); |
| 514 | if (doi_def == NULL) { |
| 515 | spin_unlock(&cipso_v4_doi_list_lock); |
| 516 | rcu_read_unlock(); |
| 517 | return -ENOENT; |
| 518 | } |
| 519 | doi_def->valid = 0; |
| 520 | list_del_rcu(&doi_def->list); |
| 521 | spin_unlock(&cipso_v4_doi_list_lock); |
| 522 | list_for_each_entry_rcu(dom_iter, &doi_def->dom_list, list) |
| 523 | if (dom_iter->valid) |
Paul Moore | 32f50cd | 2006-09-28 14:51:47 -0700 | [diff] [blame] | 524 | netlbl_domhsh_remove(dom_iter->domain, |
Paul Moore | 95d4e6b | 2006-09-29 17:05:05 -0700 | [diff] [blame] | 525 | audit_info); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 526 | cipso_v4_cache_invalidate(); |
| 527 | rcu_read_unlock(); |
| 528 | |
| 529 | call_rcu(&doi_def->rcu, callback); |
| 530 | return 0; |
| 531 | } |
| 532 | rcu_read_unlock(); |
| 533 | |
| 534 | return -ENOENT; |
| 535 | } |
| 536 | |
| 537 | /** |
| 538 | * cipso_v4_doi_getdef - Returns a pointer to a valid DOI definition |
| 539 | * @doi: the DOI value |
| 540 | * |
| 541 | * Description: |
| 542 | * Searches for a valid DOI definition and if one is found it is returned to |
| 543 | * the caller. Otherwise NULL is returned. The caller must ensure that |
| 544 | * rcu_read_lock() is held while accessing the returned definition. |
| 545 | * |
| 546 | */ |
| 547 | struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) |
| 548 | { |
| 549 | return cipso_v4_doi_search(doi); |
| 550 | } |
| 551 | |
| 552 | /** |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 553 | * cipso_v4_doi_walk - Iterate through the DOI definitions |
| 554 | * @skip_cnt: skip past this number of DOI definitions, updated |
| 555 | * @callback: callback for each DOI definition |
| 556 | * @cb_arg: argument for the callback function |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 557 | * |
| 558 | * Description: |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 559 | * Iterate over the DOI definition list, skipping the first @skip_cnt entries. |
| 560 | * For each entry call @callback, if @callback returns a negative value stop |
| 561 | * 'walking' through the list and return. Updates the value in @skip_cnt upon |
| 562 | * return. Returns zero on success, negative values on failure. |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 563 | * |
| 564 | */ |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 565 | int cipso_v4_doi_walk(u32 *skip_cnt, |
| 566 | int (*callback) (struct cipso_v4_doi *doi_def, void *arg), |
| 567 | void *cb_arg) |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 568 | { |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 569 | int ret_val = -ENOENT; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 570 | u32 doi_cnt = 0; |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 571 | struct cipso_v4_doi *iter_doi; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 572 | |
| 573 | rcu_read_lock(); |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 574 | list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) |
| 575 | if (iter_doi->valid) { |
| 576 | if (doi_cnt++ < *skip_cnt) |
| 577 | continue; |
| 578 | ret_val = callback(iter_doi, cb_arg); |
| 579 | if (ret_val < 0) { |
| 580 | doi_cnt--; |
| 581 | goto doi_walk_return; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 582 | } |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 583 | } |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 584 | |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 585 | doi_walk_return: |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 586 | rcu_read_unlock(); |
Paul Moore | fcd4828 | 2006-09-25 15:56:09 -0700 | [diff] [blame] | 587 | *skip_cnt = doi_cnt; |
| 588 | return ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 589 | } |
| 590 | |
| 591 | /** |
| 592 | * cipso_v4_doi_domhsh_add - Adds a domain entry to a DOI definition |
| 593 | * @doi_def: the DOI definition |
| 594 | * @domain: the domain to add |
| 595 | * |
| 596 | * Description: |
| 597 | * Adds the @domain to the the DOI specified by @doi_def, this function |
| 598 | * should only be called by external functions (i.e. NetLabel). This function |
| 599 | * does allocate memory. Returns zero on success, negative values on failure. |
| 600 | * |
| 601 | */ |
| 602 | int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, const char *domain) |
| 603 | { |
| 604 | struct cipso_v4_domhsh_entry *iter; |
| 605 | struct cipso_v4_domhsh_entry *new_dom; |
| 606 | |
| 607 | new_dom = kzalloc(sizeof(*new_dom), GFP_KERNEL); |
| 608 | if (new_dom == NULL) |
| 609 | return -ENOMEM; |
| 610 | if (domain) { |
| 611 | new_dom->domain = kstrdup(domain, GFP_KERNEL); |
| 612 | if (new_dom->domain == NULL) { |
| 613 | kfree(new_dom); |
| 614 | return -ENOMEM; |
| 615 | } |
| 616 | } |
| 617 | new_dom->valid = 1; |
| 618 | INIT_RCU_HEAD(&new_dom->rcu); |
| 619 | |
| 620 | rcu_read_lock(); |
| 621 | spin_lock(&cipso_v4_doi_list_lock); |
| 622 | list_for_each_entry_rcu(iter, &doi_def->dom_list, list) |
| 623 | if (iter->valid && |
| 624 | ((domain != NULL && iter->domain != NULL && |
| 625 | strcmp(iter->domain, domain) == 0) || |
| 626 | (domain == NULL && iter->domain == NULL))) { |
| 627 | spin_unlock(&cipso_v4_doi_list_lock); |
| 628 | rcu_read_unlock(); |
| 629 | kfree(new_dom->domain); |
| 630 | kfree(new_dom); |
| 631 | return -EEXIST; |
| 632 | } |
| 633 | list_add_tail_rcu(&new_dom->list, &doi_def->dom_list); |
| 634 | spin_unlock(&cipso_v4_doi_list_lock); |
| 635 | rcu_read_unlock(); |
| 636 | |
| 637 | return 0; |
| 638 | } |
| 639 | |
| 640 | /** |
| 641 | * cipso_v4_doi_domhsh_remove - Removes a domain entry from a DOI definition |
| 642 | * @doi_def: the DOI definition |
| 643 | * @domain: the domain to remove |
| 644 | * |
| 645 | * Description: |
| 646 | * Removes the @domain from the DOI specified by @doi_def, this function |
| 647 | * should only be called by external functions (i.e. NetLabel). Returns zero |
| 648 | * on success and negative values on error. |
| 649 | * |
| 650 | */ |
| 651 | int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def, |
| 652 | const char *domain) |
| 653 | { |
| 654 | struct cipso_v4_domhsh_entry *iter; |
| 655 | |
| 656 | rcu_read_lock(); |
| 657 | spin_lock(&cipso_v4_doi_list_lock); |
| 658 | list_for_each_entry_rcu(iter, &doi_def->dom_list, list) |
| 659 | if (iter->valid && |
| 660 | ((domain != NULL && iter->domain != NULL && |
| 661 | strcmp(iter->domain, domain) == 0) || |
| 662 | (domain == NULL && iter->domain == NULL))) { |
| 663 | iter->valid = 0; |
| 664 | list_del_rcu(&iter->list); |
| 665 | spin_unlock(&cipso_v4_doi_list_lock); |
| 666 | rcu_read_unlock(); |
| 667 | call_rcu(&iter->rcu, cipso_v4_doi_domhsh_free); |
| 668 | |
| 669 | return 0; |
| 670 | } |
| 671 | spin_unlock(&cipso_v4_doi_list_lock); |
| 672 | rcu_read_unlock(); |
| 673 | |
| 674 | return -ENOENT; |
| 675 | } |
| 676 | |
| 677 | /* |
| 678 | * Label Mapping Functions |
| 679 | */ |
| 680 | |
| 681 | /** |
| 682 | * cipso_v4_map_lvl_valid - Checks to see if the given level is understood |
| 683 | * @doi_def: the DOI definition |
| 684 | * @level: the level to check |
| 685 | * |
| 686 | * Description: |
| 687 | * Checks the given level against the given DOI definition and returns a |
| 688 | * negative value if the level does not have a valid mapping and a zero value |
| 689 | * if the level is defined by the DOI. |
| 690 | * |
| 691 | */ |
| 692 | static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) |
| 693 | { |
| 694 | switch (doi_def->type) { |
| 695 | case CIPSO_V4_MAP_PASS: |
| 696 | return 0; |
| 697 | case CIPSO_V4_MAP_STD: |
| 698 | if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL) |
| 699 | return 0; |
| 700 | break; |
| 701 | } |
| 702 | |
| 703 | return -EFAULT; |
| 704 | } |
| 705 | |
| 706 | /** |
| 707 | * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network |
| 708 | * @doi_def: the DOI definition |
| 709 | * @host_lvl: the host MLS level |
| 710 | * @net_lvl: the network/CIPSO MLS level |
| 711 | * |
| 712 | * Description: |
| 713 | * Perform a label mapping to translate a local MLS level to the correct |
| 714 | * CIPSO level using the given DOI definition. Returns zero on success, |
| 715 | * negative values otherwise. |
| 716 | * |
| 717 | */ |
| 718 | static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, |
| 719 | u32 host_lvl, |
| 720 | u32 *net_lvl) |
| 721 | { |
| 722 | switch (doi_def->type) { |
| 723 | case CIPSO_V4_MAP_PASS: |
| 724 | *net_lvl = host_lvl; |
| 725 | return 0; |
| 726 | case CIPSO_V4_MAP_STD: |
| 727 | if (host_lvl < doi_def->map.std->lvl.local_size) { |
| 728 | *net_lvl = doi_def->map.std->lvl.local[host_lvl]; |
| 729 | return 0; |
| 730 | } |
| 731 | break; |
| 732 | } |
| 733 | |
| 734 | return -EINVAL; |
| 735 | } |
| 736 | |
| 737 | /** |
| 738 | * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host |
| 739 | * @doi_def: the DOI definition |
| 740 | * @net_lvl: the network/CIPSO MLS level |
| 741 | * @host_lvl: the host MLS level |
| 742 | * |
| 743 | * Description: |
| 744 | * Perform a label mapping to translate a CIPSO level to the correct local MLS |
| 745 | * level using the given DOI definition. Returns zero on success, negative |
| 746 | * values otherwise. |
| 747 | * |
| 748 | */ |
| 749 | static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, |
| 750 | u32 net_lvl, |
| 751 | u32 *host_lvl) |
| 752 | { |
| 753 | struct cipso_v4_std_map_tbl *map_tbl; |
| 754 | |
| 755 | switch (doi_def->type) { |
| 756 | case CIPSO_V4_MAP_PASS: |
| 757 | *host_lvl = net_lvl; |
| 758 | return 0; |
| 759 | case CIPSO_V4_MAP_STD: |
| 760 | map_tbl = doi_def->map.std; |
| 761 | if (net_lvl < map_tbl->lvl.cipso_size && |
| 762 | map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) { |
| 763 | *host_lvl = doi_def->map.std->lvl.cipso[net_lvl]; |
| 764 | return 0; |
| 765 | } |
| 766 | break; |
| 767 | } |
| 768 | |
| 769 | return -EINVAL; |
| 770 | } |
| 771 | |
| 772 | /** |
| 773 | * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid |
| 774 | * @doi_def: the DOI definition |
| 775 | * @bitmap: category bitmap |
| 776 | * @bitmap_len: bitmap length in bytes |
| 777 | * |
| 778 | * Description: |
| 779 | * Checks the given category bitmap against the given DOI definition and |
| 780 | * returns a negative value if any of the categories in the bitmap do not have |
| 781 | * a valid mapping and a zero value if all of the categories are valid. |
| 782 | * |
| 783 | */ |
| 784 | static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, |
| 785 | const unsigned char *bitmap, |
| 786 | u32 bitmap_len) |
| 787 | { |
| 788 | int cat = -1; |
| 789 | u32 bitmap_len_bits = bitmap_len * 8; |
Paul Moore | 044a68e | 2006-10-11 19:10:47 -0400 | [diff] [blame] | 790 | u32 cipso_cat_size; |
| 791 | u32 *cipso_array; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 792 | |
| 793 | switch (doi_def->type) { |
| 794 | case CIPSO_V4_MAP_PASS: |
| 795 | return 0; |
| 796 | case CIPSO_V4_MAP_STD: |
Paul Moore | 044a68e | 2006-10-11 19:10:47 -0400 | [diff] [blame] | 797 | cipso_cat_size = doi_def->map.std->cat.cipso_size; |
| 798 | cipso_array = doi_def->map.std->cat.cipso; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 799 | for (;;) { |
| 800 | cat = cipso_v4_bitmap_walk(bitmap, |
| 801 | bitmap_len_bits, |
| 802 | cat + 1, |
| 803 | 1); |
| 804 | if (cat < 0) |
| 805 | break; |
| 806 | if (cat >= cipso_cat_size || |
| 807 | cipso_array[cat] >= CIPSO_V4_INV_CAT) |
| 808 | return -EFAULT; |
| 809 | } |
| 810 | |
| 811 | if (cat == -1) |
| 812 | return 0; |
| 813 | break; |
| 814 | } |
| 815 | |
| 816 | return -EFAULT; |
| 817 | } |
| 818 | |
| 819 | /** |
| 820 | * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network |
| 821 | * @doi_def: the DOI definition |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 822 | * @secattr: the security attributes |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 823 | * @net_cat: the zero'd out category bitmap in network/CIPSO format |
| 824 | * @net_cat_len: the length of the CIPSO bitmap in bytes |
| 825 | * |
| 826 | * Description: |
| 827 | * Perform a label mapping to translate a local MLS category bitmap to the |
| 828 | * correct CIPSO bitmap using the given DOI definition. Returns the minimum |
| 829 | * size in bytes of the network bitmap on success, negative values otherwise. |
| 830 | * |
| 831 | */ |
| 832 | static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 833 | const struct netlbl_lsm_secattr *secattr, |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 834 | unsigned char *net_cat, |
| 835 | u32 net_cat_len) |
| 836 | { |
| 837 | int host_spot = -1; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 838 | u32 net_spot = CIPSO_V4_INV_CAT; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 839 | u32 net_spot_max = 0; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 840 | u32 net_clen_bits = net_cat_len * 8; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 841 | u32 host_cat_size = 0; |
| 842 | u32 *host_cat_array = NULL; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 843 | |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 844 | if (doi_def->type == CIPSO_V4_MAP_STD) { |
Paul Moore | 044a68e | 2006-10-11 19:10:47 -0400 | [diff] [blame] | 845 | host_cat_size = doi_def->map.std->cat.local_size; |
| 846 | host_cat_array = doi_def->map.std->cat.local; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 847 | } |
| 848 | |
| 849 | for (;;) { |
| 850 | host_spot = netlbl_secattr_catmap_walk(secattr->mls_cat, |
| 851 | host_spot + 1); |
| 852 | if (host_spot < 0) |
| 853 | break; |
| 854 | |
| 855 | switch (doi_def->type) { |
| 856 | case CIPSO_V4_MAP_PASS: |
| 857 | net_spot = host_spot; |
| 858 | break; |
| 859 | case CIPSO_V4_MAP_STD: |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 860 | if (host_spot >= host_cat_size) |
| 861 | return -EPERM; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 862 | net_spot = host_cat_array[host_spot]; |
Paul Moore | 9fade4b | 2006-11-17 17:38:50 -0500 | [diff] [blame] | 863 | if (net_spot >= CIPSO_V4_INV_CAT) |
| 864 | return -EPERM; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 865 | break; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 866 | } |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 867 | if (net_spot >= net_clen_bits) |
| 868 | return -ENOSPC; |
| 869 | cipso_v4_bitmap_setbit(net_cat, net_spot, 1); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 870 | |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 871 | if (net_spot > net_spot_max) |
| 872 | net_spot_max = net_spot; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 873 | } |
| 874 | |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 875 | if (++net_spot_max % 8) |
| 876 | return net_spot_max / 8 + 1; |
| 877 | return net_spot_max / 8; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 878 | } |
| 879 | |
| 880 | /** |
| 881 | * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host |
| 882 | * @doi_def: the DOI definition |
| 883 | * @net_cat: the category bitmap in network/CIPSO format |
| 884 | * @net_cat_len: the length of the CIPSO bitmap in bytes |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 885 | * @secattr: the security attributes |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 886 | * |
| 887 | * Description: |
| 888 | * Perform a label mapping to translate a CIPSO bitmap to the correct local |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 889 | * MLS category bitmap using the given DOI definition. Returns zero on |
| 890 | * success, negative values on failure. |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 891 | * |
| 892 | */ |
| 893 | static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, |
| 894 | const unsigned char *net_cat, |
| 895 | u32 net_cat_len, |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 896 | struct netlbl_lsm_secattr *secattr) |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 897 | { |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 898 | int ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 899 | int net_spot = -1; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 900 | u32 host_spot = CIPSO_V4_INV_CAT; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 901 | u32 net_clen_bits = net_cat_len * 8; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 902 | u32 net_cat_size = 0; |
| 903 | u32 *net_cat_array = NULL; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 904 | |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 905 | if (doi_def->type == CIPSO_V4_MAP_STD) { |
Paul Moore | 044a68e | 2006-10-11 19:10:47 -0400 | [diff] [blame] | 906 | net_cat_size = doi_def->map.std->cat.cipso_size; |
| 907 | net_cat_array = doi_def->map.std->cat.cipso; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 908 | } |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 909 | |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 910 | for (;;) { |
| 911 | net_spot = cipso_v4_bitmap_walk(net_cat, |
| 912 | net_clen_bits, |
| 913 | net_spot + 1, |
| 914 | 1); |
| 915 | if (net_spot < 0) { |
| 916 | if (net_spot == -2) |
| 917 | return -EFAULT; |
| 918 | return 0; |
| 919 | } |
| 920 | |
| 921 | switch (doi_def->type) { |
| 922 | case CIPSO_V4_MAP_PASS: |
| 923 | host_spot = net_spot; |
| 924 | break; |
| 925 | case CIPSO_V4_MAP_STD: |
| 926 | if (net_spot >= net_cat_size) |
| 927 | return -EPERM; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 928 | host_spot = net_cat_array[net_spot]; |
Paul Moore | 9fade4b | 2006-11-17 17:38:50 -0500 | [diff] [blame] | 929 | if (host_spot >= CIPSO_V4_INV_CAT) |
| 930 | return -EPERM; |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 931 | break; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 932 | } |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 933 | ret_val = netlbl_secattr_catmap_setbit(secattr->mls_cat, |
| 934 | host_spot, |
| 935 | GFP_ATOMIC); |
| 936 | if (ret_val != 0) |
| 937 | return ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 938 | } |
| 939 | |
| 940 | return -EINVAL; |
| 941 | } |
| 942 | |
| 943 | /* |
| 944 | * Protocol Handling Functions |
| 945 | */ |
| 946 | |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 947 | #define CIPSO_V4_OPT_LEN_MAX 40 |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 948 | #define CIPSO_V4_HDR_LEN 6 |
| 949 | |
| 950 | /** |
| 951 | * cipso_v4_gentag_hdr - Generate a CIPSO option header |
| 952 | * @doi_def: the DOI definition |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 953 | * @len: the total tag length in bytes, not including this header |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 954 | * @buf: the CIPSO option buffer |
| 955 | * |
| 956 | * Description: |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 957 | * Write a CIPSO header into the beginning of @buffer. |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 958 | * |
| 959 | */ |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 960 | static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, |
| 961 | unsigned char *buf, |
| 962 | u32 len) |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 963 | { |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 964 | buf[0] = IPOPT_CIPSO; |
| 965 | buf[1] = CIPSO_V4_HDR_LEN + len; |
Al Viro | 714e85b | 2006-11-14 20:51:49 -0800 | [diff] [blame] | 966 | *(__be32 *)&buf[2] = htonl(doi_def->doi); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 967 | } |
| 968 | |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 969 | /** |
| 970 | * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) |
| 971 | * @doi_def: the DOI definition |
| 972 | * @secattr: the security attributes |
| 973 | * @buffer: the option buffer |
| 974 | * @buffer_len: length of buffer in bytes |
| 975 | * |
| 976 | * Description: |
| 977 | * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The |
| 978 | * actual buffer length may be larger than the indicated size due to |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 979 | * translation between host and network category bitmaps. Returns the size of |
| 980 | * the tag on success, negative values on failure. |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 981 | * |
| 982 | */ |
| 983 | static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, |
| 984 | const struct netlbl_lsm_secattr *secattr, |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 985 | unsigned char *buffer, |
| 986 | u32 buffer_len) |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 987 | { |
Paul Moore | 701a90b | 2006-11-17 17:38:46 -0500 | [diff] [blame] | 988 | int ret_val; |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 989 | u32 tag_len; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 990 | u32 level; |
| 991 | |
Paul Moore | 701a90b | 2006-11-17 17:38:46 -0500 | [diff] [blame] | 992 | if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) |
| 993 | return -EPERM; |
| 994 | |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 995 | ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level); |
| 996 | if (ret_val != 0) |
| 997 | return ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 998 | |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 999 | if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1000 | ret_val = cipso_v4_map_cat_rbm_hton(doi_def, |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 1001 | secattr, |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1002 | &buffer[4], |
| 1003 | buffer_len - 4); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1004 | if (ret_val < 0) |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1005 | return ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1006 | |
| 1007 | /* This will send packets using the "optimized" format when |
| 1008 | * possibile as specified in section 3.4.2.6 of the |
| 1009 | * CIPSO draft. */ |
Paul Moore | 701a90b | 2006-11-17 17:38:46 -0500 | [diff] [blame] | 1010 | if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1011 | tag_len = 14; |
Paul Moore | 701a90b | 2006-11-17 17:38:46 -0500 | [diff] [blame] | 1012 | else |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1013 | tag_len = 4 + ret_val; |
| 1014 | } else |
| 1015 | tag_len = 4; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1016 | |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1017 | buffer[0] = 0x01; |
| 1018 | buffer[1] = tag_len; |
| 1019 | buffer[3] = level; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1020 | |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1021 | return tag_len; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1022 | } |
| 1023 | |
| 1024 | /** |
| 1025 | * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag |
| 1026 | * @doi_def: the DOI definition |
| 1027 | * @tag: the CIPSO tag |
| 1028 | * @secattr: the security attributes |
| 1029 | * |
| 1030 | * Description: |
| 1031 | * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security |
| 1032 | * attributes in @secattr. Return zero on success, negatives values on |
| 1033 | * failure. |
| 1034 | * |
| 1035 | */ |
| 1036 | static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, |
| 1037 | const unsigned char *tag, |
| 1038 | struct netlbl_lsm_secattr *secattr) |
| 1039 | { |
| 1040 | int ret_val; |
| 1041 | u8 tag_len = tag[1]; |
| 1042 | u32 level; |
| 1043 | |
| 1044 | ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level); |
| 1045 | if (ret_val != 0) |
| 1046 | return ret_val; |
| 1047 | secattr->mls_lvl = level; |
Paul Moore | 701a90b | 2006-11-17 17:38:46 -0500 | [diff] [blame] | 1048 | secattr->flags |= NETLBL_SECATTR_MLS_LVL; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1049 | |
| 1050 | if (tag_len > 4) { |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 1051 | secattr->mls_cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1052 | if (secattr->mls_cat == NULL) |
| 1053 | return -ENOMEM; |
| 1054 | |
| 1055 | ret_val = cipso_v4_map_cat_rbm_ntoh(doi_def, |
| 1056 | &tag[4], |
| 1057 | tag_len - 4, |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 1058 | secattr); |
| 1059 | if (ret_val != 0) { |
| 1060 | netlbl_secattr_catmap_free(secattr->mls_cat); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1061 | return ret_val; |
| 1062 | } |
Paul Moore | 0275276 | 2006-11-29 13:18:18 -0500 | [diff] [blame^] | 1063 | |
| 1064 | secattr->flags |= NETLBL_SECATTR_MLS_CAT; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1065 | } |
| 1066 | |
| 1067 | return 0; |
| 1068 | } |
| 1069 | |
| 1070 | /** |
| 1071 | * cipso_v4_validate - Validate a CIPSO option |
| 1072 | * @option: the start of the option, on error it is set to point to the error |
| 1073 | * |
| 1074 | * Description: |
| 1075 | * This routine is called to validate a CIPSO option, it checks all of the |
| 1076 | * fields to ensure that they are at least valid, see the draft snippet below |
| 1077 | * for details. If the option is valid then a zero value is returned and |
| 1078 | * the value of @option is unchanged. If the option is invalid then a |
| 1079 | * non-zero value is returned and @option is adjusted to point to the |
| 1080 | * offending portion of the option. From the IETF draft ... |
| 1081 | * |
| 1082 | * "If any field within the CIPSO options, such as the DOI identifier, is not |
| 1083 | * recognized the IP datagram is discarded and an ICMP 'parameter problem' |
| 1084 | * (type 12) is generated and returned. The ICMP code field is set to 'bad |
| 1085 | * parameter' (code 0) and the pointer is set to the start of the CIPSO field |
| 1086 | * that is unrecognized." |
| 1087 | * |
| 1088 | */ |
| 1089 | int cipso_v4_validate(unsigned char **option) |
| 1090 | { |
| 1091 | unsigned char *opt = *option; |
| 1092 | unsigned char *tag; |
| 1093 | unsigned char opt_iter; |
| 1094 | unsigned char err_offset = 0; |
| 1095 | u8 opt_len; |
| 1096 | u8 tag_len; |
| 1097 | struct cipso_v4_doi *doi_def = NULL; |
| 1098 | u32 tag_iter; |
| 1099 | |
| 1100 | /* caller already checks for length values that are too large */ |
| 1101 | opt_len = opt[1]; |
| 1102 | if (opt_len < 8) { |
| 1103 | err_offset = 1; |
| 1104 | goto validate_return; |
| 1105 | } |
| 1106 | |
| 1107 | rcu_read_lock(); |
Al Viro | 6662598 | 2006-11-20 18:08:37 -0800 | [diff] [blame] | 1108 | doi_def = cipso_v4_doi_search(ntohl(*((__be32 *)&opt[2]))); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1109 | if (doi_def == NULL) { |
| 1110 | err_offset = 2; |
| 1111 | goto validate_return_locked; |
| 1112 | } |
| 1113 | |
| 1114 | opt_iter = 6; |
| 1115 | tag = opt + opt_iter; |
| 1116 | while (opt_iter < opt_len) { |
| 1117 | for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];) |
| 1118 | if (doi_def->tags[tag_iter] == CIPSO_V4_TAG_INVALID || |
| 1119 | ++tag_iter == CIPSO_V4_TAG_MAXCNT) { |
| 1120 | err_offset = opt_iter; |
| 1121 | goto validate_return_locked; |
| 1122 | } |
| 1123 | |
| 1124 | tag_len = tag[1]; |
| 1125 | if (tag_len > (opt_len - opt_iter)) { |
| 1126 | err_offset = opt_iter + 1; |
| 1127 | goto validate_return_locked; |
| 1128 | } |
| 1129 | |
| 1130 | switch (tag[0]) { |
| 1131 | case CIPSO_V4_TAG_RBITMAP: |
| 1132 | if (tag_len < 4) { |
| 1133 | err_offset = opt_iter + 1; |
| 1134 | goto validate_return_locked; |
| 1135 | } |
| 1136 | |
| 1137 | /* We are already going to do all the verification |
| 1138 | * necessary at the socket layer so from our point of |
| 1139 | * view it is safe to turn these checks off (and less |
| 1140 | * work), however, the CIPSO draft says we should do |
| 1141 | * all the CIPSO validations here but it doesn't |
| 1142 | * really specify _exactly_ what we need to validate |
| 1143 | * ... so, just make it a sysctl tunable. */ |
| 1144 | if (cipso_v4_rbm_strictvalid) { |
| 1145 | if (cipso_v4_map_lvl_valid(doi_def, |
| 1146 | tag[3]) < 0) { |
| 1147 | err_offset = opt_iter + 3; |
| 1148 | goto validate_return_locked; |
| 1149 | } |
| 1150 | if (tag_len > 4 && |
| 1151 | cipso_v4_map_cat_rbm_valid(doi_def, |
| 1152 | &tag[4], |
| 1153 | tag_len - 4) < 0) { |
| 1154 | err_offset = opt_iter + 4; |
| 1155 | goto validate_return_locked; |
| 1156 | } |
| 1157 | } |
| 1158 | break; |
| 1159 | default: |
| 1160 | err_offset = opt_iter; |
| 1161 | goto validate_return_locked; |
| 1162 | } |
| 1163 | |
| 1164 | tag += tag_len; |
| 1165 | opt_iter += tag_len; |
| 1166 | } |
| 1167 | |
| 1168 | validate_return_locked: |
| 1169 | rcu_read_unlock(); |
| 1170 | validate_return: |
| 1171 | *option = opt + err_offset; |
| 1172 | return err_offset; |
| 1173 | } |
| 1174 | |
| 1175 | /** |
| 1176 | * cipso_v4_error - Send the correct reponse for a bad packet |
| 1177 | * @skb: the packet |
| 1178 | * @error: the error code |
| 1179 | * @gateway: CIPSO gateway flag |
| 1180 | * |
| 1181 | * Description: |
| 1182 | * Based on the error code given in @error, send an ICMP error message back to |
| 1183 | * the originating host. From the IETF draft ... |
| 1184 | * |
| 1185 | * "If the contents of the CIPSO [option] are valid but the security label is |
| 1186 | * outside of the configured host or port label range, the datagram is |
| 1187 | * discarded and an ICMP 'destination unreachable' (type 3) is generated and |
| 1188 | * returned. The code field of the ICMP is set to 'communication with |
| 1189 | * destination network administratively prohibited' (code 9) or to |
| 1190 | * 'communication with destination host administratively prohibited' |
| 1191 | * (code 10). The value of the code is dependent on whether the originator |
| 1192 | * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The |
| 1193 | * recipient of the ICMP message MUST be able to handle either value. The |
| 1194 | * same procedure is performed if a CIPSO [option] can not be added to an |
| 1195 | * IP packet because it is too large to fit in the IP options area." |
| 1196 | * |
| 1197 | * "If the error is triggered by receipt of an ICMP message, the message is |
| 1198 | * discarded and no response is permitted (consistent with general ICMP |
| 1199 | * processing rules)." |
| 1200 | * |
| 1201 | */ |
| 1202 | void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) |
| 1203 | { |
| 1204 | if (skb->nh.iph->protocol == IPPROTO_ICMP || error != -EACCES) |
| 1205 | return; |
| 1206 | |
| 1207 | if (gateway) |
| 1208 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0); |
| 1209 | else |
| 1210 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0); |
| 1211 | } |
| 1212 | |
| 1213 | /** |
| 1214 | * cipso_v4_socket_setattr - Add a CIPSO option to a socket |
| 1215 | * @sock: the socket |
| 1216 | * @doi_def: the CIPSO DOI to use |
| 1217 | * @secattr: the specific security attributes of the socket |
| 1218 | * |
| 1219 | * Description: |
| 1220 | * Set the CIPSO option on the given socket using the DOI definition and |
| 1221 | * security attributes passed to the function. This function requires |
| 1222 | * exclusive access to @sock->sk, which means it either needs to be in the |
| 1223 | * process of being created or locked via lock_sock(sock->sk). Returns zero on |
| 1224 | * success and negative values on failure. |
| 1225 | * |
| 1226 | */ |
| 1227 | int cipso_v4_socket_setattr(const struct socket *sock, |
| 1228 | const struct cipso_v4_doi *doi_def, |
| 1229 | const struct netlbl_lsm_secattr *secattr) |
| 1230 | { |
| 1231 | int ret_val = -EPERM; |
| 1232 | u32 iter; |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1233 | unsigned char *buf; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1234 | u32 buf_len = 0; |
| 1235 | u32 opt_len; |
| 1236 | struct ip_options *opt = NULL; |
| 1237 | struct sock *sk; |
| 1238 | struct inet_sock *sk_inet; |
| 1239 | struct inet_connection_sock *sk_conn; |
| 1240 | |
| 1241 | /* In the case of sock_create_lite(), the sock->sk field is not |
| 1242 | * defined yet but it is not a problem as the only users of these |
| 1243 | * "lite" PF_INET sockets are functions which do an accept() call |
| 1244 | * afterwards so we will label the socket as part of the accept(). */ |
| 1245 | sk = sock->sk; |
| 1246 | if (sk == NULL) |
| 1247 | return 0; |
| 1248 | |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1249 | /* We allocate the maximum CIPSO option size here so we are probably |
| 1250 | * being a little wasteful, but it makes our life _much_ easier later |
| 1251 | * on and after all we are only talking about 40 bytes. */ |
| 1252 | buf_len = CIPSO_V4_OPT_LEN_MAX; |
| 1253 | buf = kmalloc(buf_len, GFP_ATOMIC); |
| 1254 | if (buf == NULL) { |
| 1255 | ret_val = -ENOMEM; |
| 1256 | goto socket_setattr_failure; |
| 1257 | } |
| 1258 | |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1259 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
| 1260 | * really a good assumption to make but since we only support the MAC |
| 1261 | * tags right now it is a safe assumption. */ |
| 1262 | iter = 0; |
| 1263 | do { |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1264 | memset(buf, 0, buf_len); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1265 | switch (doi_def->tags[iter]) { |
| 1266 | case CIPSO_V4_TAG_RBITMAP: |
| 1267 | ret_val = cipso_v4_gentag_rbm(doi_def, |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1268 | secattr, |
| 1269 | &buf[CIPSO_V4_HDR_LEN], |
| 1270 | buf_len - CIPSO_V4_HDR_LEN); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1271 | break; |
| 1272 | default: |
| 1273 | ret_val = -EPERM; |
| 1274 | goto socket_setattr_failure; |
| 1275 | } |
| 1276 | |
| 1277 | iter++; |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1278 | } while (ret_val < 0 && |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1279 | iter < CIPSO_V4_TAG_MAXCNT && |
| 1280 | doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1281 | if (ret_val < 0) |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1282 | goto socket_setattr_failure; |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1283 | cipso_v4_gentag_hdr(doi_def, buf, ret_val); |
| 1284 | buf_len = CIPSO_V4_HDR_LEN + ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1285 | |
| 1286 | /* We can't use ip_options_get() directly because it makes a call to |
| 1287 | * ip_options_get_alloc() which allocates memory with GFP_KERNEL and |
Paul Moore | f8687af | 2006-10-30 15:22:15 -0800 | [diff] [blame] | 1288 | * we won't always have CAP_NET_RAW even though we _always_ want to |
| 1289 | * set the IPOPT_CIPSO option. */ |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1290 | opt_len = (buf_len + 3) & ~3; |
| 1291 | opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC); |
| 1292 | if (opt == NULL) { |
| 1293 | ret_val = -ENOMEM; |
| 1294 | goto socket_setattr_failure; |
| 1295 | } |
| 1296 | memcpy(opt->__data, buf, buf_len); |
| 1297 | opt->optlen = opt_len; |
| 1298 | opt->is_data = 1; |
Paul Moore | f8687af | 2006-10-30 15:22:15 -0800 | [diff] [blame] | 1299 | opt->cipso = sizeof(struct iphdr); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1300 | kfree(buf); |
| 1301 | buf = NULL; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1302 | |
| 1303 | sk_inet = inet_sk(sk); |
| 1304 | if (sk_inet->is_icsk) { |
| 1305 | sk_conn = inet_csk(sk); |
| 1306 | if (sk_inet->opt) |
| 1307 | sk_conn->icsk_ext_hdr_len -= sk_inet->opt->optlen; |
| 1308 | sk_conn->icsk_ext_hdr_len += opt->optlen; |
| 1309 | sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); |
| 1310 | } |
| 1311 | opt = xchg(&sk_inet->opt, opt); |
| 1312 | kfree(opt); |
| 1313 | |
| 1314 | return 0; |
| 1315 | |
| 1316 | socket_setattr_failure: |
| 1317 | kfree(buf); |
| 1318 | kfree(opt); |
| 1319 | return ret_val; |
| 1320 | } |
| 1321 | |
| 1322 | /** |
Paul Moore | 14a72f5 | 2006-09-25 15:52:01 -0700 | [diff] [blame] | 1323 | * cipso_v4_sock_getattr - Get the security attributes from a sock |
| 1324 | * @sk: the sock |
| 1325 | * @secattr: the security attributes |
| 1326 | * |
| 1327 | * Description: |
| 1328 | * Query @sk to see if there is a CIPSO option attached to the sock and if |
| 1329 | * there is return the CIPSO security attributes in @secattr. This function |
| 1330 | * requires that @sk be locked, or privately held, but it does not do any |
| 1331 | * locking itself. Returns zero on success and negative values on failure. |
| 1332 | * |
| 1333 | */ |
| 1334 | int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) |
| 1335 | { |
| 1336 | int ret_val = -ENOMSG; |
| 1337 | struct inet_sock *sk_inet; |
| 1338 | unsigned char *cipso_ptr; |
| 1339 | u32 doi; |
| 1340 | struct cipso_v4_doi *doi_def; |
| 1341 | |
| 1342 | sk_inet = inet_sk(sk); |
| 1343 | if (sk_inet->opt == NULL || sk_inet->opt->cipso == 0) |
| 1344 | return -ENOMSG; |
| 1345 | cipso_ptr = sk_inet->opt->__data + sk_inet->opt->cipso - |
| 1346 | sizeof(struct iphdr); |
| 1347 | ret_val = cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr); |
| 1348 | if (ret_val == 0) |
| 1349 | return ret_val; |
| 1350 | |
Al Viro | 714e85b | 2006-11-14 20:51:49 -0800 | [diff] [blame] | 1351 | doi = ntohl(*(__be32 *)&cipso_ptr[2]); |
Paul Moore | 14a72f5 | 2006-09-25 15:52:01 -0700 | [diff] [blame] | 1352 | rcu_read_lock(); |
Paul Moore | 9bb5fd2 | 2006-11-17 17:38:52 -0500 | [diff] [blame] | 1353 | doi_def = cipso_v4_doi_search(doi); |
Paul Moore | 14a72f5 | 2006-09-25 15:52:01 -0700 | [diff] [blame] | 1354 | if (doi_def == NULL) { |
| 1355 | rcu_read_unlock(); |
| 1356 | return -ENOMSG; |
| 1357 | } |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1358 | |
| 1359 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
| 1360 | * really a good assumption to make but since we only support the MAC |
| 1361 | * tags right now it is a safe assumption. */ |
Paul Moore | 14a72f5 | 2006-09-25 15:52:01 -0700 | [diff] [blame] | 1362 | switch (cipso_ptr[6]) { |
| 1363 | case CIPSO_V4_TAG_RBITMAP: |
| 1364 | ret_val = cipso_v4_parsetag_rbm(doi_def, |
| 1365 | &cipso_ptr[6], |
| 1366 | secattr); |
| 1367 | break; |
| 1368 | } |
| 1369 | rcu_read_unlock(); |
| 1370 | |
| 1371 | return ret_val; |
| 1372 | } |
| 1373 | |
| 1374 | /** |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1375 | * cipso_v4_socket_getattr - Get the security attributes from a socket |
| 1376 | * @sock: the socket |
| 1377 | * @secattr: the security attributes |
| 1378 | * |
| 1379 | * Description: |
| 1380 | * Query @sock to see if there is a CIPSO option attached to the socket and if |
| 1381 | * there is return the CIPSO security attributes in @secattr. Returns zero on |
| 1382 | * success and negative values on failure. |
| 1383 | * |
| 1384 | */ |
| 1385 | int cipso_v4_socket_getattr(const struct socket *sock, |
| 1386 | struct netlbl_lsm_secattr *secattr) |
| 1387 | { |
Paul Moore | 14a72f5 | 2006-09-25 15:52:01 -0700 | [diff] [blame] | 1388 | int ret_val; |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1389 | |
Paul Moore | 14a72f5 | 2006-09-25 15:52:01 -0700 | [diff] [blame] | 1390 | lock_sock(sock->sk); |
| 1391 | ret_val = cipso_v4_sock_getattr(sock->sk, secattr); |
| 1392 | release_sock(sock->sk); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1393 | |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1394 | return ret_val; |
| 1395 | } |
| 1396 | |
| 1397 | /** |
| 1398 | * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option |
| 1399 | * @skb: the packet |
| 1400 | * @secattr: the security attributes |
| 1401 | * |
| 1402 | * Description: |
| 1403 | * Parse the given packet's CIPSO option and return the security attributes. |
| 1404 | * Returns zero on success and negative values on failure. |
| 1405 | * |
| 1406 | */ |
| 1407 | int cipso_v4_skbuff_getattr(const struct sk_buff *skb, |
| 1408 | struct netlbl_lsm_secattr *secattr) |
| 1409 | { |
| 1410 | int ret_val = -ENOMSG; |
| 1411 | unsigned char *cipso_ptr; |
| 1412 | u32 doi; |
| 1413 | struct cipso_v4_doi *doi_def; |
| 1414 | |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1415 | cipso_ptr = CIPSO_V4_OPTPTR(skb); |
| 1416 | if (cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr) == 0) |
| 1417 | return 0; |
| 1418 | |
Al Viro | 714e85b | 2006-11-14 20:51:49 -0800 | [diff] [blame] | 1419 | doi = ntohl(*(__be32 *)&cipso_ptr[2]); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1420 | rcu_read_lock(); |
Paul Moore | 9bb5fd2 | 2006-11-17 17:38:52 -0500 | [diff] [blame] | 1421 | doi_def = cipso_v4_doi_search(doi); |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1422 | if (doi_def == NULL) |
| 1423 | goto skbuff_getattr_return; |
Paul Moore | 91b1ed0 | 2006-11-17 17:38:49 -0500 | [diff] [blame] | 1424 | |
| 1425 | /* XXX - This code assumes only one tag per CIPSO option which isn't |
| 1426 | * really a good assumption to make but since we only support the MAC |
| 1427 | * tags right now it is a safe assumption. */ |
Paul Moore | 446fda4 | 2006-08-03 16:48:06 -0700 | [diff] [blame] | 1428 | switch (cipso_ptr[6]) { |
| 1429 | case CIPSO_V4_TAG_RBITMAP: |
| 1430 | ret_val = cipso_v4_parsetag_rbm(doi_def, |
| 1431 | &cipso_ptr[6], |
| 1432 | secattr); |
| 1433 | break; |
| 1434 | } |
| 1435 | |
| 1436 | skbuff_getattr_return: |
| 1437 | rcu_read_unlock(); |
| 1438 | return ret_val; |
| 1439 | } |
| 1440 | |
| 1441 | /* |
| 1442 | * Setup Functions |
| 1443 | */ |
| 1444 | |
| 1445 | /** |
| 1446 | * cipso_v4_init - Initialize the CIPSO module |
| 1447 | * |
| 1448 | * Description: |
| 1449 | * Initialize the CIPSO module and prepare it for use. Returns zero on success |
| 1450 | * and negative values on failure. |
| 1451 | * |
| 1452 | */ |
| 1453 | static int __init cipso_v4_init(void) |
| 1454 | { |
| 1455 | int ret_val; |
| 1456 | |
| 1457 | ret_val = cipso_v4_cache_init(); |
| 1458 | if (ret_val != 0) |
| 1459 | panic("Failed to initialize the CIPSO/IPv4 cache (%d)\n", |
| 1460 | ret_val); |
| 1461 | |
| 1462 | return 0; |
| 1463 | } |
| 1464 | |
| 1465 | subsys_initcall(cipso_v4_init); |