Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * xfrm_policy.c |
| 3 | * |
| 4 | * Changes: |
| 5 | * Mitsuru KANDA @USAGI |
| 6 | * Kazunori MIYAZAWA @USAGI |
| 7 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> |
| 8 | * IPv6 support |
| 9 | * Kazunori MIYAZAWA @USAGI |
| 10 | * YOSHIFUJI Hideaki |
| 11 | * Split up af-specific portion |
| 12 | * Derek Atkins <derek@ihtfp.com> Add the post_input processor |
| 13 | * |
| 14 | */ |
| 15 | |
| 16 | #include <asm/bug.h> |
| 17 | #include <linux/config.h> |
| 18 | #include <linux/slab.h> |
| 19 | #include <linux/kmod.h> |
| 20 | #include <linux/list.h> |
| 21 | #include <linux/spinlock.h> |
| 22 | #include <linux/workqueue.h> |
| 23 | #include <linux/notifier.h> |
| 24 | #include <linux/netdevice.h> |
| 25 | #include <linux/module.h> |
| 26 | #include <net/xfrm.h> |
| 27 | #include <net/ip.h> |
| 28 | |
| 29 | DECLARE_MUTEX(xfrm_cfg_sem); |
| 30 | EXPORT_SYMBOL(xfrm_cfg_sem); |
| 31 | |
| 32 | static DEFINE_RWLOCK(xfrm_policy_lock); |
| 33 | |
| 34 | struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2]; |
| 35 | EXPORT_SYMBOL(xfrm_policy_list); |
| 36 | |
| 37 | static DEFINE_RWLOCK(xfrm_policy_afinfo_lock); |
| 38 | static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO]; |
| 39 | |
| 40 | static kmem_cache_t *xfrm_dst_cache; |
| 41 | |
| 42 | static struct work_struct xfrm_policy_gc_work; |
| 43 | static struct list_head xfrm_policy_gc_list = |
| 44 | LIST_HEAD_INIT(xfrm_policy_gc_list); |
| 45 | static DEFINE_SPINLOCK(xfrm_policy_gc_lock); |
| 46 | |
| 47 | static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family); |
| 48 | static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo); |
| 49 | |
| 50 | int xfrm_register_type(struct xfrm_type *type, unsigned short family) |
| 51 | { |
| 52 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| 53 | struct xfrm_type_map *typemap; |
| 54 | int err = 0; |
| 55 | |
| 56 | if (unlikely(afinfo == NULL)) |
| 57 | return -EAFNOSUPPORT; |
| 58 | typemap = afinfo->type_map; |
| 59 | |
| 60 | write_lock(&typemap->lock); |
| 61 | if (likely(typemap->map[type->proto] == NULL)) |
| 62 | typemap->map[type->proto] = type; |
| 63 | else |
| 64 | err = -EEXIST; |
| 65 | write_unlock(&typemap->lock); |
| 66 | xfrm_policy_put_afinfo(afinfo); |
| 67 | return err; |
| 68 | } |
| 69 | EXPORT_SYMBOL(xfrm_register_type); |
| 70 | |
| 71 | int xfrm_unregister_type(struct xfrm_type *type, unsigned short family) |
| 72 | { |
| 73 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| 74 | struct xfrm_type_map *typemap; |
| 75 | int err = 0; |
| 76 | |
| 77 | if (unlikely(afinfo == NULL)) |
| 78 | return -EAFNOSUPPORT; |
| 79 | typemap = afinfo->type_map; |
| 80 | |
| 81 | write_lock(&typemap->lock); |
| 82 | if (unlikely(typemap->map[type->proto] != type)) |
| 83 | err = -ENOENT; |
| 84 | else |
| 85 | typemap->map[type->proto] = NULL; |
| 86 | write_unlock(&typemap->lock); |
| 87 | xfrm_policy_put_afinfo(afinfo); |
| 88 | return err; |
| 89 | } |
| 90 | EXPORT_SYMBOL(xfrm_unregister_type); |
| 91 | |
| 92 | struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family) |
| 93 | { |
| 94 | struct xfrm_policy_afinfo *afinfo; |
| 95 | struct xfrm_type_map *typemap; |
| 96 | struct xfrm_type *type; |
| 97 | int modload_attempted = 0; |
| 98 | |
| 99 | retry: |
| 100 | afinfo = xfrm_policy_get_afinfo(family); |
| 101 | if (unlikely(afinfo == NULL)) |
| 102 | return NULL; |
| 103 | typemap = afinfo->type_map; |
| 104 | |
| 105 | read_lock(&typemap->lock); |
| 106 | type = typemap->map[proto]; |
| 107 | if (unlikely(type && !try_module_get(type->owner))) |
| 108 | type = NULL; |
| 109 | read_unlock(&typemap->lock); |
| 110 | if (!type && !modload_attempted) { |
| 111 | xfrm_policy_put_afinfo(afinfo); |
| 112 | request_module("xfrm-type-%d-%d", |
| 113 | (int) family, (int) proto); |
| 114 | modload_attempted = 1; |
| 115 | goto retry; |
| 116 | } |
| 117 | |
| 118 | xfrm_policy_put_afinfo(afinfo); |
| 119 | return type; |
| 120 | } |
| 121 | EXPORT_SYMBOL(xfrm_get_type); |
| 122 | |
| 123 | int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, |
| 124 | unsigned short family) |
| 125 | { |
| 126 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| 127 | int err = 0; |
| 128 | |
| 129 | if (unlikely(afinfo == NULL)) |
| 130 | return -EAFNOSUPPORT; |
| 131 | |
| 132 | if (likely(afinfo->dst_lookup != NULL)) |
| 133 | err = afinfo->dst_lookup(dst, fl); |
| 134 | else |
| 135 | err = -EINVAL; |
| 136 | xfrm_policy_put_afinfo(afinfo); |
| 137 | return err; |
| 138 | } |
| 139 | EXPORT_SYMBOL(xfrm_dst_lookup); |
| 140 | |
| 141 | void xfrm_put_type(struct xfrm_type *type) |
| 142 | { |
| 143 | module_put(type->owner); |
| 144 | } |
| 145 | |
| 146 | static inline unsigned long make_jiffies(long secs) |
| 147 | { |
| 148 | if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) |
| 149 | return MAX_SCHEDULE_TIMEOUT-1; |
| 150 | else |
| 151 | return secs*HZ; |
| 152 | } |
| 153 | |
| 154 | static void xfrm_policy_timer(unsigned long data) |
| 155 | { |
| 156 | struct xfrm_policy *xp = (struct xfrm_policy*)data; |
| 157 | unsigned long now = (unsigned long)xtime.tv_sec; |
| 158 | long next = LONG_MAX; |
| 159 | int warn = 0; |
| 160 | int dir; |
| 161 | |
| 162 | read_lock(&xp->lock); |
| 163 | |
| 164 | if (xp->dead) |
| 165 | goto out; |
| 166 | |
| 167 | dir = xp->index & 7; |
| 168 | |
| 169 | if (xp->lft.hard_add_expires_seconds) { |
| 170 | long tmo = xp->lft.hard_add_expires_seconds + |
| 171 | xp->curlft.add_time - now; |
| 172 | if (tmo <= 0) |
| 173 | goto expired; |
| 174 | if (tmo < next) |
| 175 | next = tmo; |
| 176 | } |
| 177 | if (xp->lft.hard_use_expires_seconds) { |
| 178 | long tmo = xp->lft.hard_use_expires_seconds + |
| 179 | (xp->curlft.use_time ? : xp->curlft.add_time) - now; |
| 180 | if (tmo <= 0) |
| 181 | goto expired; |
| 182 | if (tmo < next) |
| 183 | next = tmo; |
| 184 | } |
| 185 | if (xp->lft.soft_add_expires_seconds) { |
| 186 | long tmo = xp->lft.soft_add_expires_seconds + |
| 187 | xp->curlft.add_time - now; |
| 188 | if (tmo <= 0) { |
| 189 | warn = 1; |
| 190 | tmo = XFRM_KM_TIMEOUT; |
| 191 | } |
| 192 | if (tmo < next) |
| 193 | next = tmo; |
| 194 | } |
| 195 | if (xp->lft.soft_use_expires_seconds) { |
| 196 | long tmo = xp->lft.soft_use_expires_seconds + |
| 197 | (xp->curlft.use_time ? : xp->curlft.add_time) - now; |
| 198 | if (tmo <= 0) { |
| 199 | warn = 1; |
| 200 | tmo = XFRM_KM_TIMEOUT; |
| 201 | } |
| 202 | if (tmo < next) |
| 203 | next = tmo; |
| 204 | } |
| 205 | |
| 206 | if (warn) |
| 207 | km_policy_expired(xp, dir, 0); |
| 208 | if (next != LONG_MAX && |
| 209 | !mod_timer(&xp->timer, jiffies + make_jiffies(next))) |
| 210 | xfrm_pol_hold(xp); |
| 211 | |
| 212 | out: |
| 213 | read_unlock(&xp->lock); |
| 214 | xfrm_pol_put(xp); |
| 215 | return; |
| 216 | |
| 217 | expired: |
| 218 | read_unlock(&xp->lock); |
| 219 | km_policy_expired(xp, dir, 1); |
| 220 | xfrm_policy_delete(xp, dir); |
| 221 | xfrm_pol_put(xp); |
| 222 | } |
| 223 | |
| 224 | |
| 225 | /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 |
| 226 | * SPD calls. |
| 227 | */ |
| 228 | |
| 229 | struct xfrm_policy *xfrm_policy_alloc(int gfp) |
| 230 | { |
| 231 | struct xfrm_policy *policy; |
| 232 | |
| 233 | policy = kmalloc(sizeof(struct xfrm_policy), gfp); |
| 234 | |
| 235 | if (policy) { |
| 236 | memset(policy, 0, sizeof(struct xfrm_policy)); |
| 237 | atomic_set(&policy->refcnt, 1); |
| 238 | rwlock_init(&policy->lock); |
| 239 | init_timer(&policy->timer); |
| 240 | policy->timer.data = (unsigned long)policy; |
| 241 | policy->timer.function = xfrm_policy_timer; |
| 242 | } |
| 243 | return policy; |
| 244 | } |
| 245 | EXPORT_SYMBOL(xfrm_policy_alloc); |
| 246 | |
| 247 | /* Destroy xfrm_policy: descendant resources must be released to this moment. */ |
| 248 | |
| 249 | void __xfrm_policy_destroy(struct xfrm_policy *policy) |
| 250 | { |
| 251 | if (!policy->dead) |
| 252 | BUG(); |
| 253 | |
| 254 | if (policy->bundles) |
| 255 | BUG(); |
| 256 | |
| 257 | if (del_timer(&policy->timer)) |
| 258 | BUG(); |
| 259 | |
| 260 | kfree(policy); |
| 261 | } |
| 262 | EXPORT_SYMBOL(__xfrm_policy_destroy); |
| 263 | |
| 264 | static void xfrm_policy_gc_kill(struct xfrm_policy *policy) |
| 265 | { |
| 266 | struct dst_entry *dst; |
| 267 | |
| 268 | while ((dst = policy->bundles) != NULL) { |
| 269 | policy->bundles = dst->next; |
| 270 | dst_free(dst); |
| 271 | } |
| 272 | |
| 273 | if (del_timer(&policy->timer)) |
| 274 | atomic_dec(&policy->refcnt); |
| 275 | |
| 276 | if (atomic_read(&policy->refcnt) > 1) |
| 277 | flow_cache_flush(); |
| 278 | |
| 279 | xfrm_pol_put(policy); |
| 280 | } |
| 281 | |
| 282 | static void xfrm_policy_gc_task(void *data) |
| 283 | { |
| 284 | struct xfrm_policy *policy; |
| 285 | struct list_head *entry, *tmp; |
| 286 | struct list_head gc_list = LIST_HEAD_INIT(gc_list); |
| 287 | |
| 288 | spin_lock_bh(&xfrm_policy_gc_lock); |
| 289 | list_splice_init(&xfrm_policy_gc_list, &gc_list); |
| 290 | spin_unlock_bh(&xfrm_policy_gc_lock); |
| 291 | |
| 292 | list_for_each_safe(entry, tmp, &gc_list) { |
| 293 | policy = list_entry(entry, struct xfrm_policy, list); |
| 294 | xfrm_policy_gc_kill(policy); |
| 295 | } |
| 296 | } |
| 297 | |
| 298 | /* Rule must be locked. Release descentant resources, announce |
| 299 | * entry dead. The rule must be unlinked from lists to the moment. |
| 300 | */ |
| 301 | |
| 302 | static void xfrm_policy_kill(struct xfrm_policy *policy) |
| 303 | { |
| 304 | int dead; |
| 305 | |
| 306 | write_lock_bh(&policy->lock); |
| 307 | dead = policy->dead; |
| 308 | policy->dead = 1; |
| 309 | write_unlock_bh(&policy->lock); |
| 310 | |
| 311 | if (unlikely(dead)) { |
| 312 | WARN_ON(1); |
| 313 | return; |
| 314 | } |
| 315 | |
| 316 | spin_lock(&xfrm_policy_gc_lock); |
| 317 | list_add(&policy->list, &xfrm_policy_gc_list); |
| 318 | spin_unlock(&xfrm_policy_gc_lock); |
| 319 | |
| 320 | schedule_work(&xfrm_policy_gc_work); |
| 321 | } |
| 322 | |
| 323 | /* Generate new index... KAME seems to generate them ordered by cost |
| 324 | * of an absolute inpredictability of ordering of rules. This will not pass. */ |
| 325 | static u32 xfrm_gen_index(int dir) |
| 326 | { |
| 327 | u32 idx; |
| 328 | struct xfrm_policy *p; |
| 329 | static u32 idx_generator; |
| 330 | |
| 331 | for (;;) { |
| 332 | idx = (idx_generator | dir); |
| 333 | idx_generator += 8; |
| 334 | if (idx == 0) |
| 335 | idx = 8; |
| 336 | for (p = xfrm_policy_list[dir]; p; p = p->next) { |
| 337 | if (p->index == idx) |
| 338 | break; |
| 339 | } |
| 340 | if (!p) |
| 341 | return idx; |
| 342 | } |
| 343 | } |
| 344 | |
| 345 | int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) |
| 346 | { |
| 347 | struct xfrm_policy *pol, **p; |
| 348 | struct xfrm_policy *delpol = NULL; |
| 349 | struct xfrm_policy **newpos = NULL; |
| 350 | |
| 351 | write_lock_bh(&xfrm_policy_lock); |
| 352 | for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL;) { |
| 353 | if (!delpol && memcmp(&policy->selector, &pol->selector, sizeof(pol->selector)) == 0) { |
| 354 | if (excl) { |
| 355 | write_unlock_bh(&xfrm_policy_lock); |
| 356 | return -EEXIST; |
| 357 | } |
| 358 | *p = pol->next; |
| 359 | delpol = pol; |
| 360 | if (policy->priority > pol->priority) |
| 361 | continue; |
| 362 | } else if (policy->priority >= pol->priority) { |
| 363 | p = &pol->next; |
| 364 | continue; |
| 365 | } |
| 366 | if (!newpos) |
| 367 | newpos = p; |
| 368 | if (delpol) |
| 369 | break; |
| 370 | p = &pol->next; |
| 371 | } |
| 372 | if (newpos) |
| 373 | p = newpos; |
| 374 | xfrm_pol_hold(policy); |
| 375 | policy->next = *p; |
| 376 | *p = policy; |
| 377 | atomic_inc(&flow_cache_genid); |
| 378 | policy->index = delpol ? delpol->index : xfrm_gen_index(dir); |
| 379 | policy->curlft.add_time = (unsigned long)xtime.tv_sec; |
| 380 | policy->curlft.use_time = 0; |
| 381 | if (!mod_timer(&policy->timer, jiffies + HZ)) |
| 382 | xfrm_pol_hold(policy); |
| 383 | write_unlock_bh(&xfrm_policy_lock); |
| 384 | |
| 385 | if (delpol) { |
| 386 | xfrm_policy_kill(delpol); |
| 387 | } |
| 388 | return 0; |
| 389 | } |
| 390 | EXPORT_SYMBOL(xfrm_policy_insert); |
| 391 | |
| 392 | struct xfrm_policy *xfrm_policy_bysel(int dir, struct xfrm_selector *sel, |
| 393 | int delete) |
| 394 | { |
| 395 | struct xfrm_policy *pol, **p; |
| 396 | |
| 397 | write_lock_bh(&xfrm_policy_lock); |
| 398 | for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) { |
| 399 | if (memcmp(sel, &pol->selector, sizeof(*sel)) == 0) { |
| 400 | xfrm_pol_hold(pol); |
| 401 | if (delete) |
| 402 | *p = pol->next; |
| 403 | break; |
| 404 | } |
| 405 | } |
| 406 | write_unlock_bh(&xfrm_policy_lock); |
| 407 | |
| 408 | if (pol && delete) { |
| 409 | atomic_inc(&flow_cache_genid); |
| 410 | xfrm_policy_kill(pol); |
| 411 | } |
| 412 | return pol; |
| 413 | } |
| 414 | EXPORT_SYMBOL(xfrm_policy_bysel); |
| 415 | |
| 416 | struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete) |
| 417 | { |
| 418 | struct xfrm_policy *pol, **p; |
| 419 | |
| 420 | write_lock_bh(&xfrm_policy_lock); |
| 421 | for (p = &xfrm_policy_list[id & 7]; (pol=*p)!=NULL; p = &pol->next) { |
| 422 | if (pol->index == id) { |
| 423 | xfrm_pol_hold(pol); |
| 424 | if (delete) |
| 425 | *p = pol->next; |
| 426 | break; |
| 427 | } |
| 428 | } |
| 429 | write_unlock_bh(&xfrm_policy_lock); |
| 430 | |
| 431 | if (pol && delete) { |
| 432 | atomic_inc(&flow_cache_genid); |
| 433 | xfrm_policy_kill(pol); |
| 434 | } |
| 435 | return pol; |
| 436 | } |
| 437 | EXPORT_SYMBOL(xfrm_policy_byid); |
| 438 | |
| 439 | void xfrm_policy_flush(void) |
| 440 | { |
| 441 | struct xfrm_policy *xp; |
| 442 | int dir; |
| 443 | |
| 444 | write_lock_bh(&xfrm_policy_lock); |
| 445 | for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { |
| 446 | while ((xp = xfrm_policy_list[dir]) != NULL) { |
| 447 | xfrm_policy_list[dir] = xp->next; |
| 448 | write_unlock_bh(&xfrm_policy_lock); |
| 449 | |
| 450 | xfrm_policy_kill(xp); |
| 451 | |
| 452 | write_lock_bh(&xfrm_policy_lock); |
| 453 | } |
| 454 | } |
| 455 | atomic_inc(&flow_cache_genid); |
| 456 | write_unlock_bh(&xfrm_policy_lock); |
| 457 | } |
| 458 | EXPORT_SYMBOL(xfrm_policy_flush); |
| 459 | |
| 460 | int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), |
| 461 | void *data) |
| 462 | { |
| 463 | struct xfrm_policy *xp; |
| 464 | int dir; |
| 465 | int count = 0; |
| 466 | int error = 0; |
| 467 | |
| 468 | read_lock_bh(&xfrm_policy_lock); |
| 469 | for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) { |
| 470 | for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) |
| 471 | count++; |
| 472 | } |
| 473 | |
| 474 | if (count == 0) { |
| 475 | error = -ENOENT; |
| 476 | goto out; |
| 477 | } |
| 478 | |
| 479 | for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) { |
| 480 | for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) { |
| 481 | error = func(xp, dir%XFRM_POLICY_MAX, --count, data); |
| 482 | if (error) |
| 483 | goto out; |
| 484 | } |
| 485 | } |
| 486 | |
| 487 | out: |
| 488 | read_unlock_bh(&xfrm_policy_lock); |
| 489 | return error; |
| 490 | } |
| 491 | EXPORT_SYMBOL(xfrm_policy_walk); |
| 492 | |
| 493 | /* Find policy to apply to this flow. */ |
| 494 | |
| 495 | static void xfrm_policy_lookup(struct flowi *fl, u16 family, u8 dir, |
| 496 | void **objp, atomic_t **obj_refp) |
| 497 | { |
| 498 | struct xfrm_policy *pol; |
| 499 | |
| 500 | read_lock_bh(&xfrm_policy_lock); |
| 501 | for (pol = xfrm_policy_list[dir]; pol; pol = pol->next) { |
| 502 | struct xfrm_selector *sel = &pol->selector; |
| 503 | int match; |
| 504 | |
| 505 | if (pol->family != family) |
| 506 | continue; |
| 507 | |
| 508 | match = xfrm_selector_match(sel, fl, family); |
| 509 | if (match) { |
| 510 | xfrm_pol_hold(pol); |
| 511 | break; |
| 512 | } |
| 513 | } |
| 514 | read_unlock_bh(&xfrm_policy_lock); |
| 515 | if ((*objp = (void *) pol) != NULL) |
| 516 | *obj_refp = &pol->refcnt; |
| 517 | } |
| 518 | |
| 519 | static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl) |
| 520 | { |
| 521 | struct xfrm_policy *pol; |
| 522 | |
| 523 | read_lock_bh(&xfrm_policy_lock); |
| 524 | if ((pol = sk->sk_policy[dir]) != NULL) { |
| 525 | int match = xfrm_selector_match(&pol->selector, fl, |
| 526 | sk->sk_family); |
| 527 | if (match) |
| 528 | xfrm_pol_hold(pol); |
| 529 | else |
| 530 | pol = NULL; |
| 531 | } |
| 532 | read_unlock_bh(&xfrm_policy_lock); |
| 533 | return pol; |
| 534 | } |
| 535 | |
| 536 | static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) |
| 537 | { |
| 538 | pol->next = xfrm_policy_list[dir]; |
| 539 | xfrm_policy_list[dir] = pol; |
| 540 | xfrm_pol_hold(pol); |
| 541 | } |
| 542 | |
| 543 | static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, |
| 544 | int dir) |
| 545 | { |
| 546 | struct xfrm_policy **polp; |
| 547 | |
| 548 | for (polp = &xfrm_policy_list[dir]; |
| 549 | *polp != NULL; polp = &(*polp)->next) { |
| 550 | if (*polp == pol) { |
| 551 | *polp = pol->next; |
| 552 | return pol; |
| 553 | } |
| 554 | } |
| 555 | return NULL; |
| 556 | } |
| 557 | |
| 558 | void xfrm_policy_delete(struct xfrm_policy *pol, int dir) |
| 559 | { |
| 560 | write_lock_bh(&xfrm_policy_lock); |
| 561 | pol = __xfrm_policy_unlink(pol, dir); |
| 562 | write_unlock_bh(&xfrm_policy_lock); |
| 563 | if (pol) { |
| 564 | if (dir < XFRM_POLICY_MAX) |
| 565 | atomic_inc(&flow_cache_genid); |
| 566 | xfrm_policy_kill(pol); |
| 567 | } |
| 568 | } |
| 569 | |
| 570 | int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) |
| 571 | { |
| 572 | struct xfrm_policy *old_pol; |
| 573 | |
| 574 | write_lock_bh(&xfrm_policy_lock); |
| 575 | old_pol = sk->sk_policy[dir]; |
| 576 | sk->sk_policy[dir] = pol; |
| 577 | if (pol) { |
| 578 | pol->curlft.add_time = (unsigned long)xtime.tv_sec; |
| 579 | pol->index = xfrm_gen_index(XFRM_POLICY_MAX+dir); |
| 580 | __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir); |
| 581 | } |
| 582 | if (old_pol) |
| 583 | __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir); |
| 584 | write_unlock_bh(&xfrm_policy_lock); |
| 585 | |
| 586 | if (old_pol) { |
| 587 | xfrm_policy_kill(old_pol); |
| 588 | } |
| 589 | return 0; |
| 590 | } |
| 591 | |
| 592 | static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir) |
| 593 | { |
| 594 | struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC); |
| 595 | |
| 596 | if (newp) { |
| 597 | newp->selector = old->selector; |
| 598 | newp->lft = old->lft; |
| 599 | newp->curlft = old->curlft; |
| 600 | newp->action = old->action; |
| 601 | newp->flags = old->flags; |
| 602 | newp->xfrm_nr = old->xfrm_nr; |
| 603 | newp->index = old->index; |
| 604 | memcpy(newp->xfrm_vec, old->xfrm_vec, |
| 605 | newp->xfrm_nr*sizeof(struct xfrm_tmpl)); |
| 606 | write_lock_bh(&xfrm_policy_lock); |
| 607 | __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir); |
| 608 | write_unlock_bh(&xfrm_policy_lock); |
| 609 | xfrm_pol_put(newp); |
| 610 | } |
| 611 | return newp; |
| 612 | } |
| 613 | |
| 614 | int __xfrm_sk_clone_policy(struct sock *sk) |
| 615 | { |
| 616 | struct xfrm_policy *p0 = sk->sk_policy[0], |
| 617 | *p1 = sk->sk_policy[1]; |
| 618 | |
| 619 | sk->sk_policy[0] = sk->sk_policy[1] = NULL; |
| 620 | if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL) |
| 621 | return -ENOMEM; |
| 622 | if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL) |
| 623 | return -ENOMEM; |
| 624 | return 0; |
| 625 | } |
| 626 | |
| 627 | /* Resolve list of templates for the flow, given policy. */ |
| 628 | |
| 629 | static int |
| 630 | xfrm_tmpl_resolve(struct xfrm_policy *policy, struct flowi *fl, |
| 631 | struct xfrm_state **xfrm, |
| 632 | unsigned short family) |
| 633 | { |
| 634 | int nx; |
| 635 | int i, error; |
| 636 | xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); |
| 637 | xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); |
| 638 | |
| 639 | for (nx=0, i = 0; i < policy->xfrm_nr; i++) { |
| 640 | struct xfrm_state *x; |
| 641 | xfrm_address_t *remote = daddr; |
| 642 | xfrm_address_t *local = saddr; |
| 643 | struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; |
| 644 | |
| 645 | if (tmpl->mode) { |
| 646 | remote = &tmpl->id.daddr; |
| 647 | local = &tmpl->saddr; |
| 648 | } |
| 649 | |
| 650 | x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); |
| 651 | |
| 652 | if (x && x->km.state == XFRM_STATE_VALID) { |
| 653 | xfrm[nx++] = x; |
| 654 | daddr = remote; |
| 655 | saddr = local; |
| 656 | continue; |
| 657 | } |
| 658 | if (x) { |
| 659 | error = (x->km.state == XFRM_STATE_ERROR ? |
| 660 | -EINVAL : -EAGAIN); |
| 661 | xfrm_state_put(x); |
| 662 | } |
| 663 | |
| 664 | if (!tmpl->optional) |
| 665 | goto fail; |
| 666 | } |
| 667 | return nx; |
| 668 | |
| 669 | fail: |
| 670 | for (nx--; nx>=0; nx--) |
| 671 | xfrm_state_put(xfrm[nx]); |
| 672 | return error; |
| 673 | } |
| 674 | |
| 675 | /* Check that the bundle accepts the flow and its components are |
| 676 | * still valid. |
| 677 | */ |
| 678 | |
| 679 | static struct dst_entry * |
| 680 | xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family) |
| 681 | { |
| 682 | struct dst_entry *x; |
| 683 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| 684 | if (unlikely(afinfo == NULL)) |
| 685 | return ERR_PTR(-EINVAL); |
| 686 | x = afinfo->find_bundle(fl, policy); |
| 687 | xfrm_policy_put_afinfo(afinfo); |
| 688 | return x; |
| 689 | } |
| 690 | |
| 691 | /* Allocate chain of dst_entry's, attach known xfrm's, calculate |
| 692 | * all the metrics... Shortly, bundle a bundle. |
| 693 | */ |
| 694 | |
| 695 | static int |
| 696 | xfrm_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx, |
| 697 | struct flowi *fl, struct dst_entry **dst_p, |
| 698 | unsigned short family) |
| 699 | { |
| 700 | int err; |
| 701 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| 702 | if (unlikely(afinfo == NULL)) |
| 703 | return -EINVAL; |
| 704 | err = afinfo->bundle_create(policy, xfrm, nx, fl, dst_p); |
| 705 | xfrm_policy_put_afinfo(afinfo); |
| 706 | return err; |
| 707 | } |
| 708 | |
| 709 | static inline int policy_to_flow_dir(int dir) |
| 710 | { |
| 711 | if (XFRM_POLICY_IN == FLOW_DIR_IN && |
| 712 | XFRM_POLICY_OUT == FLOW_DIR_OUT && |
| 713 | XFRM_POLICY_FWD == FLOW_DIR_FWD) |
| 714 | return dir; |
| 715 | switch (dir) { |
| 716 | default: |
| 717 | case XFRM_POLICY_IN: |
| 718 | return FLOW_DIR_IN; |
| 719 | case XFRM_POLICY_OUT: |
| 720 | return FLOW_DIR_OUT; |
| 721 | case XFRM_POLICY_FWD: |
| 722 | return FLOW_DIR_FWD; |
| 723 | }; |
| 724 | } |
| 725 | |
| 726 | static int stale_bundle(struct dst_entry *dst); |
| 727 | |
| 728 | /* Main function: finds/creates a bundle for given flow. |
| 729 | * |
| 730 | * At the moment we eat a raw IP route. Mostly to speed up lookups |
| 731 | * on interfaces with disabled IPsec. |
| 732 | */ |
| 733 | int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl, |
| 734 | struct sock *sk, int flags) |
| 735 | { |
| 736 | struct xfrm_policy *policy; |
| 737 | struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; |
| 738 | struct dst_entry *dst, *dst_orig = *dst_p; |
| 739 | int nx = 0; |
| 740 | int err; |
| 741 | u32 genid; |
| 742 | u16 family = dst_orig->ops->family; |
| 743 | restart: |
| 744 | genid = atomic_read(&flow_cache_genid); |
| 745 | policy = NULL; |
| 746 | if (sk && sk->sk_policy[1]) |
| 747 | policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl); |
| 748 | |
| 749 | if (!policy) { |
| 750 | /* To accelerate a bit... */ |
| 751 | if ((dst_orig->flags & DST_NOXFRM) || !xfrm_policy_list[XFRM_POLICY_OUT]) |
| 752 | return 0; |
| 753 | |
| 754 | policy = flow_cache_lookup(fl, family, |
| 755 | policy_to_flow_dir(XFRM_POLICY_OUT), |
| 756 | xfrm_policy_lookup); |
| 757 | } |
| 758 | |
| 759 | if (!policy) |
| 760 | return 0; |
| 761 | |
| 762 | policy->curlft.use_time = (unsigned long)xtime.tv_sec; |
| 763 | |
| 764 | switch (policy->action) { |
| 765 | case XFRM_POLICY_BLOCK: |
| 766 | /* Prohibit the flow */ |
| 767 | xfrm_pol_put(policy); |
| 768 | return -EPERM; |
| 769 | |
| 770 | case XFRM_POLICY_ALLOW: |
| 771 | if (policy->xfrm_nr == 0) { |
| 772 | /* Flow passes not transformed. */ |
| 773 | xfrm_pol_put(policy); |
| 774 | return 0; |
| 775 | } |
| 776 | |
| 777 | /* Try to find matching bundle. |
| 778 | * |
| 779 | * LATER: help from flow cache. It is optional, this |
| 780 | * is required only for output policy. |
| 781 | */ |
| 782 | dst = xfrm_find_bundle(fl, policy, family); |
| 783 | if (IS_ERR(dst)) { |
| 784 | xfrm_pol_put(policy); |
| 785 | return PTR_ERR(dst); |
| 786 | } |
| 787 | |
| 788 | if (dst) |
| 789 | break; |
| 790 | |
| 791 | nx = xfrm_tmpl_resolve(policy, fl, xfrm, family); |
| 792 | |
| 793 | if (unlikely(nx<0)) { |
| 794 | err = nx; |
| 795 | if (err == -EAGAIN && flags) { |
| 796 | DECLARE_WAITQUEUE(wait, current); |
| 797 | |
| 798 | add_wait_queue(&km_waitq, &wait); |
| 799 | set_current_state(TASK_INTERRUPTIBLE); |
| 800 | schedule(); |
| 801 | set_current_state(TASK_RUNNING); |
| 802 | remove_wait_queue(&km_waitq, &wait); |
| 803 | |
| 804 | nx = xfrm_tmpl_resolve(policy, fl, xfrm, family); |
| 805 | |
| 806 | if (nx == -EAGAIN && signal_pending(current)) { |
| 807 | err = -ERESTART; |
| 808 | goto error; |
| 809 | } |
| 810 | if (nx == -EAGAIN || |
| 811 | genid != atomic_read(&flow_cache_genid)) { |
| 812 | xfrm_pol_put(policy); |
| 813 | goto restart; |
| 814 | } |
| 815 | err = nx; |
| 816 | } |
| 817 | if (err < 0) |
| 818 | goto error; |
| 819 | } |
| 820 | if (nx == 0) { |
| 821 | /* Flow passes not transformed. */ |
| 822 | xfrm_pol_put(policy); |
| 823 | return 0; |
| 824 | } |
| 825 | |
| 826 | dst = dst_orig; |
| 827 | err = xfrm_bundle_create(policy, xfrm, nx, fl, &dst, family); |
| 828 | |
| 829 | if (unlikely(err)) { |
| 830 | int i; |
| 831 | for (i=0; i<nx; i++) |
| 832 | xfrm_state_put(xfrm[i]); |
| 833 | goto error; |
| 834 | } |
| 835 | |
| 836 | write_lock_bh(&policy->lock); |
| 837 | if (unlikely(policy->dead || stale_bundle(dst))) { |
| 838 | /* Wow! While we worked on resolving, this |
| 839 | * policy has gone. Retry. It is not paranoia, |
| 840 | * we just cannot enlist new bundle to dead object. |
| 841 | * We can't enlist stable bundles either. |
| 842 | */ |
| 843 | write_unlock_bh(&policy->lock); |
| 844 | |
| 845 | xfrm_pol_put(policy); |
| 846 | if (dst) |
| 847 | dst_free(dst); |
| 848 | goto restart; |
| 849 | } |
| 850 | dst->next = policy->bundles; |
| 851 | policy->bundles = dst; |
| 852 | dst_hold(dst); |
| 853 | write_unlock_bh(&policy->lock); |
| 854 | } |
| 855 | *dst_p = dst; |
| 856 | dst_release(dst_orig); |
| 857 | xfrm_pol_put(policy); |
| 858 | return 0; |
| 859 | |
| 860 | error: |
| 861 | dst_release(dst_orig); |
| 862 | xfrm_pol_put(policy); |
| 863 | *dst_p = NULL; |
| 864 | return err; |
| 865 | } |
| 866 | EXPORT_SYMBOL(xfrm_lookup); |
| 867 | |
| 868 | /* When skb is transformed back to its "native" form, we have to |
| 869 | * check policy restrictions. At the moment we make this in maximally |
| 870 | * stupid way. Shame on me. :-) Of course, connected sockets must |
| 871 | * have policy cached at them. |
| 872 | */ |
| 873 | |
| 874 | static inline int |
| 875 | xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x, |
| 876 | unsigned short family) |
| 877 | { |
| 878 | if (xfrm_state_kern(x)) |
| 879 | return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, family); |
| 880 | return x->id.proto == tmpl->id.proto && |
| 881 | (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && |
| 882 | (x->props.reqid == tmpl->reqid || !tmpl->reqid) && |
| 883 | x->props.mode == tmpl->mode && |
| 884 | (tmpl->aalgos & (1<<x->props.aalgo)) && |
| 885 | !(x->props.mode && xfrm_state_addr_cmp(tmpl, x, family)); |
| 886 | } |
| 887 | |
| 888 | static inline int |
| 889 | xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start, |
| 890 | unsigned short family) |
| 891 | { |
| 892 | int idx = start; |
| 893 | |
| 894 | if (tmpl->optional) { |
| 895 | if (!tmpl->mode) |
| 896 | return start; |
| 897 | } else |
| 898 | start = -1; |
| 899 | for (; idx < sp->len; idx++) { |
| 900 | if (xfrm_state_ok(tmpl, sp->x[idx].xvec, family)) |
| 901 | return ++idx; |
| 902 | if (sp->x[idx].xvec->props.mode) |
| 903 | break; |
| 904 | } |
| 905 | return start; |
| 906 | } |
| 907 | |
| 908 | static int |
| 909 | _decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family) |
| 910 | { |
| 911 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| 912 | |
| 913 | if (unlikely(afinfo == NULL)) |
| 914 | return -EAFNOSUPPORT; |
| 915 | |
| 916 | afinfo->decode_session(skb, fl); |
| 917 | xfrm_policy_put_afinfo(afinfo); |
| 918 | return 0; |
| 919 | } |
| 920 | |
| 921 | static inline int secpath_has_tunnel(struct sec_path *sp, int k) |
| 922 | { |
| 923 | for (; k < sp->len; k++) { |
| 924 | if (sp->x[k].xvec->props.mode) |
| 925 | return 1; |
| 926 | } |
| 927 | |
| 928 | return 0; |
| 929 | } |
| 930 | |
| 931 | int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, |
| 932 | unsigned short family) |
| 933 | { |
| 934 | struct xfrm_policy *pol; |
| 935 | struct flowi fl; |
| 936 | |
| 937 | if (_decode_session(skb, &fl, family) < 0) |
| 938 | return 0; |
| 939 | |
| 940 | /* First, check used SA against their selectors. */ |
| 941 | if (skb->sp) { |
| 942 | int i; |
| 943 | |
| 944 | for (i=skb->sp->len-1; i>=0; i--) { |
| 945 | struct sec_decap_state *xvec = &(skb->sp->x[i]); |
| 946 | if (!xfrm_selector_match(&xvec->xvec->sel, &fl, family)) |
| 947 | return 0; |
| 948 | |
| 949 | /* If there is a post_input processor, try running it */ |
| 950 | if (xvec->xvec->type->post_input && |
| 951 | (xvec->xvec->type->post_input)(xvec->xvec, |
| 952 | &(xvec->decap), |
| 953 | skb) != 0) |
| 954 | return 0; |
| 955 | } |
| 956 | } |
| 957 | |
| 958 | pol = NULL; |
| 959 | if (sk && sk->sk_policy[dir]) |
| 960 | pol = xfrm_sk_policy_lookup(sk, dir, &fl); |
| 961 | |
| 962 | if (!pol) |
| 963 | pol = flow_cache_lookup(&fl, family, |
| 964 | policy_to_flow_dir(dir), |
| 965 | xfrm_policy_lookup); |
| 966 | |
| 967 | if (!pol) |
| 968 | return !skb->sp || !secpath_has_tunnel(skb->sp, 0); |
| 969 | |
| 970 | pol->curlft.use_time = (unsigned long)xtime.tv_sec; |
| 971 | |
| 972 | if (pol->action == XFRM_POLICY_ALLOW) { |
| 973 | struct sec_path *sp; |
| 974 | static struct sec_path dummy; |
| 975 | int i, k; |
| 976 | |
| 977 | if ((sp = skb->sp) == NULL) |
| 978 | sp = &dummy; |
| 979 | |
| 980 | /* For each tunnel xfrm, find the first matching tmpl. |
| 981 | * For each tmpl before that, find corresponding xfrm. |
| 982 | * Order is _important_. Later we will implement |
| 983 | * some barriers, but at the moment barriers |
| 984 | * are implied between each two transformations. |
| 985 | */ |
| 986 | for (i = pol->xfrm_nr-1, k = 0; i >= 0; i--) { |
| 987 | k = xfrm_policy_ok(pol->xfrm_vec+i, sp, k, family); |
| 988 | if (k < 0) |
| 989 | goto reject; |
| 990 | } |
| 991 | |
| 992 | if (secpath_has_tunnel(sp, k)) |
| 993 | goto reject; |
| 994 | |
| 995 | xfrm_pol_put(pol); |
| 996 | return 1; |
| 997 | } |
| 998 | |
| 999 | reject: |
| 1000 | xfrm_pol_put(pol); |
| 1001 | return 0; |
| 1002 | } |
| 1003 | EXPORT_SYMBOL(__xfrm_policy_check); |
| 1004 | |
| 1005 | int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) |
| 1006 | { |
| 1007 | struct flowi fl; |
| 1008 | |
| 1009 | if (_decode_session(skb, &fl, family) < 0) |
| 1010 | return 0; |
| 1011 | |
| 1012 | return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0; |
| 1013 | } |
| 1014 | EXPORT_SYMBOL(__xfrm_route_forward); |
| 1015 | |
| 1016 | /* Optimize later using cookies and generation ids. */ |
| 1017 | |
| 1018 | static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) |
| 1019 | { |
| 1020 | if (!stale_bundle(dst)) |
| 1021 | return dst; |
| 1022 | |
| 1023 | return NULL; |
| 1024 | } |
| 1025 | |
| 1026 | static int stale_bundle(struct dst_entry *dst) |
| 1027 | { |
| 1028 | return !xfrm_bundle_ok((struct xfrm_dst *)dst, NULL, AF_UNSPEC); |
| 1029 | } |
| 1030 | |
Herbert Xu | aabc976 | 2005-05-03 16:27:10 -0700 | [diff] [blame^] | 1031 | void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1032 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1033 | while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { |
| 1034 | dst->dev = &loopback_dev; |
| 1035 | dev_hold(&loopback_dev); |
| 1036 | dev_put(dev); |
| 1037 | } |
| 1038 | } |
Herbert Xu | aabc976 | 2005-05-03 16:27:10 -0700 | [diff] [blame^] | 1039 | EXPORT_SYMBOL(xfrm_dst_ifdown); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1040 | |
| 1041 | static void xfrm_link_failure(struct sk_buff *skb) |
| 1042 | { |
| 1043 | /* Impossible. Such dst must be popped before reaches point of failure. */ |
| 1044 | return; |
| 1045 | } |
| 1046 | |
| 1047 | static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) |
| 1048 | { |
| 1049 | if (dst) { |
| 1050 | if (dst->obsolete) { |
| 1051 | dst_release(dst); |
| 1052 | dst = NULL; |
| 1053 | } |
| 1054 | } |
| 1055 | return dst; |
| 1056 | } |
| 1057 | |
| 1058 | static void xfrm_prune_bundles(int (*func)(struct dst_entry *)) |
| 1059 | { |
| 1060 | int i; |
| 1061 | struct xfrm_policy *pol; |
| 1062 | struct dst_entry *dst, **dstp, *gc_list = NULL; |
| 1063 | |
| 1064 | read_lock_bh(&xfrm_policy_lock); |
| 1065 | for (i=0; i<2*XFRM_POLICY_MAX; i++) { |
| 1066 | for (pol = xfrm_policy_list[i]; pol; pol = pol->next) { |
| 1067 | write_lock(&pol->lock); |
| 1068 | dstp = &pol->bundles; |
| 1069 | while ((dst=*dstp) != NULL) { |
| 1070 | if (func(dst)) { |
| 1071 | *dstp = dst->next; |
| 1072 | dst->next = gc_list; |
| 1073 | gc_list = dst; |
| 1074 | } else { |
| 1075 | dstp = &dst->next; |
| 1076 | } |
| 1077 | } |
| 1078 | write_unlock(&pol->lock); |
| 1079 | } |
| 1080 | } |
| 1081 | read_unlock_bh(&xfrm_policy_lock); |
| 1082 | |
| 1083 | while (gc_list) { |
| 1084 | dst = gc_list; |
| 1085 | gc_list = dst->next; |
| 1086 | dst_free(dst); |
| 1087 | } |
| 1088 | } |
| 1089 | |
| 1090 | static int unused_bundle(struct dst_entry *dst) |
| 1091 | { |
| 1092 | return !atomic_read(&dst->__refcnt); |
| 1093 | } |
| 1094 | |
| 1095 | static void __xfrm_garbage_collect(void) |
| 1096 | { |
| 1097 | xfrm_prune_bundles(unused_bundle); |
| 1098 | } |
| 1099 | |
| 1100 | int xfrm_flush_bundles(void) |
| 1101 | { |
| 1102 | xfrm_prune_bundles(stale_bundle); |
| 1103 | return 0; |
| 1104 | } |
| 1105 | |
| 1106 | void xfrm_init_pmtu(struct dst_entry *dst) |
| 1107 | { |
| 1108 | do { |
| 1109 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; |
| 1110 | u32 pmtu, route_mtu_cached; |
| 1111 | |
| 1112 | pmtu = dst_mtu(dst->child); |
| 1113 | xdst->child_mtu_cached = pmtu; |
| 1114 | |
| 1115 | pmtu = xfrm_state_mtu(dst->xfrm, pmtu); |
| 1116 | |
| 1117 | route_mtu_cached = dst_mtu(xdst->route); |
| 1118 | xdst->route_mtu_cached = route_mtu_cached; |
| 1119 | |
| 1120 | if (pmtu > route_mtu_cached) |
| 1121 | pmtu = route_mtu_cached; |
| 1122 | |
| 1123 | dst->metrics[RTAX_MTU-1] = pmtu; |
| 1124 | } while ((dst = dst->next)); |
| 1125 | } |
| 1126 | |
| 1127 | EXPORT_SYMBOL(xfrm_init_pmtu); |
| 1128 | |
| 1129 | /* Check that the bundle accepts the flow and its components are |
| 1130 | * still valid. |
| 1131 | */ |
| 1132 | |
| 1133 | int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family) |
| 1134 | { |
| 1135 | struct dst_entry *dst = &first->u.dst; |
| 1136 | struct xfrm_dst *last; |
| 1137 | u32 mtu; |
| 1138 | |
| 1139 | if (!dst_check(dst->path, 0) || |
| 1140 | (dst->dev && !netif_running(dst->dev))) |
| 1141 | return 0; |
| 1142 | |
| 1143 | last = NULL; |
| 1144 | |
| 1145 | do { |
| 1146 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; |
| 1147 | |
| 1148 | if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family)) |
| 1149 | return 0; |
| 1150 | if (dst->xfrm->km.state != XFRM_STATE_VALID) |
| 1151 | return 0; |
| 1152 | |
| 1153 | mtu = dst_mtu(dst->child); |
| 1154 | if (xdst->child_mtu_cached != mtu) { |
| 1155 | last = xdst; |
| 1156 | xdst->child_mtu_cached = mtu; |
| 1157 | } |
| 1158 | |
| 1159 | if (!dst_check(xdst->route, 0)) |
| 1160 | return 0; |
| 1161 | mtu = dst_mtu(xdst->route); |
| 1162 | if (xdst->route_mtu_cached != mtu) { |
| 1163 | last = xdst; |
| 1164 | xdst->route_mtu_cached = mtu; |
| 1165 | } |
| 1166 | |
| 1167 | dst = dst->child; |
| 1168 | } while (dst->xfrm); |
| 1169 | |
| 1170 | if (likely(!last)) |
| 1171 | return 1; |
| 1172 | |
| 1173 | mtu = last->child_mtu_cached; |
| 1174 | for (;;) { |
| 1175 | dst = &last->u.dst; |
| 1176 | |
| 1177 | mtu = xfrm_state_mtu(dst->xfrm, mtu); |
| 1178 | if (mtu > last->route_mtu_cached) |
| 1179 | mtu = last->route_mtu_cached; |
| 1180 | dst->metrics[RTAX_MTU-1] = mtu; |
| 1181 | |
| 1182 | if (last == first) |
| 1183 | break; |
| 1184 | |
| 1185 | last = last->u.next; |
| 1186 | last->child_mtu_cached = mtu; |
| 1187 | } |
| 1188 | |
| 1189 | return 1; |
| 1190 | } |
| 1191 | |
| 1192 | EXPORT_SYMBOL(xfrm_bundle_ok); |
| 1193 | |
| 1194 | /* Well... that's _TASK_. We need to scan through transformation |
| 1195 | * list and figure out what mss tcp should generate in order to |
| 1196 | * final datagram fit to mtu. Mama mia... :-) |
| 1197 | * |
| 1198 | * Apparently, some easy way exists, but we used to choose the most |
| 1199 | * bizarre ones. :-) So, raising Kalashnikov... tra-ta-ta. |
| 1200 | * |
| 1201 | * Consider this function as something like dark humour. :-) |
| 1202 | */ |
| 1203 | static int xfrm_get_mss(struct dst_entry *dst, u32 mtu) |
| 1204 | { |
| 1205 | int res = mtu - dst->header_len; |
| 1206 | |
| 1207 | for (;;) { |
| 1208 | struct dst_entry *d = dst; |
| 1209 | int m = res; |
| 1210 | |
| 1211 | do { |
| 1212 | struct xfrm_state *x = d->xfrm; |
| 1213 | if (x) { |
| 1214 | spin_lock_bh(&x->lock); |
| 1215 | if (x->km.state == XFRM_STATE_VALID && |
| 1216 | x->type && x->type->get_max_size) |
| 1217 | m = x->type->get_max_size(d->xfrm, m); |
| 1218 | else |
| 1219 | m += x->props.header_len; |
| 1220 | spin_unlock_bh(&x->lock); |
| 1221 | } |
| 1222 | } while ((d = d->child) != NULL); |
| 1223 | |
| 1224 | if (m <= mtu) |
| 1225 | break; |
| 1226 | res -= (m - mtu); |
| 1227 | if (res < 88) |
| 1228 | return mtu; |
| 1229 | } |
| 1230 | |
| 1231 | return res + dst->header_len; |
| 1232 | } |
| 1233 | |
| 1234 | int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo) |
| 1235 | { |
| 1236 | int err = 0; |
| 1237 | if (unlikely(afinfo == NULL)) |
| 1238 | return -EINVAL; |
| 1239 | if (unlikely(afinfo->family >= NPROTO)) |
| 1240 | return -EAFNOSUPPORT; |
| 1241 | write_lock(&xfrm_policy_afinfo_lock); |
| 1242 | if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL)) |
| 1243 | err = -ENOBUFS; |
| 1244 | else { |
| 1245 | struct dst_ops *dst_ops = afinfo->dst_ops; |
| 1246 | if (likely(dst_ops->kmem_cachep == NULL)) |
| 1247 | dst_ops->kmem_cachep = xfrm_dst_cache; |
| 1248 | if (likely(dst_ops->check == NULL)) |
| 1249 | dst_ops->check = xfrm_dst_check; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1250 | if (likely(dst_ops->negative_advice == NULL)) |
| 1251 | dst_ops->negative_advice = xfrm_negative_advice; |
| 1252 | if (likely(dst_ops->link_failure == NULL)) |
| 1253 | dst_ops->link_failure = xfrm_link_failure; |
| 1254 | if (likely(dst_ops->get_mss == NULL)) |
| 1255 | dst_ops->get_mss = xfrm_get_mss; |
| 1256 | if (likely(afinfo->garbage_collect == NULL)) |
| 1257 | afinfo->garbage_collect = __xfrm_garbage_collect; |
| 1258 | xfrm_policy_afinfo[afinfo->family] = afinfo; |
| 1259 | } |
| 1260 | write_unlock(&xfrm_policy_afinfo_lock); |
| 1261 | return err; |
| 1262 | } |
| 1263 | EXPORT_SYMBOL(xfrm_policy_register_afinfo); |
| 1264 | |
| 1265 | int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo) |
| 1266 | { |
| 1267 | int err = 0; |
| 1268 | if (unlikely(afinfo == NULL)) |
| 1269 | return -EINVAL; |
| 1270 | if (unlikely(afinfo->family >= NPROTO)) |
| 1271 | return -EAFNOSUPPORT; |
| 1272 | write_lock(&xfrm_policy_afinfo_lock); |
| 1273 | if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) { |
| 1274 | if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo)) |
| 1275 | err = -EINVAL; |
| 1276 | else { |
| 1277 | struct dst_ops *dst_ops = afinfo->dst_ops; |
| 1278 | xfrm_policy_afinfo[afinfo->family] = NULL; |
| 1279 | dst_ops->kmem_cachep = NULL; |
| 1280 | dst_ops->check = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1281 | dst_ops->negative_advice = NULL; |
| 1282 | dst_ops->link_failure = NULL; |
| 1283 | dst_ops->get_mss = NULL; |
| 1284 | afinfo->garbage_collect = NULL; |
| 1285 | } |
| 1286 | } |
| 1287 | write_unlock(&xfrm_policy_afinfo_lock); |
| 1288 | return err; |
| 1289 | } |
| 1290 | EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); |
| 1291 | |
| 1292 | static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) |
| 1293 | { |
| 1294 | struct xfrm_policy_afinfo *afinfo; |
| 1295 | if (unlikely(family >= NPROTO)) |
| 1296 | return NULL; |
| 1297 | read_lock(&xfrm_policy_afinfo_lock); |
| 1298 | afinfo = xfrm_policy_afinfo[family]; |
| 1299 | if (likely(afinfo != NULL)) |
| 1300 | read_lock(&afinfo->lock); |
| 1301 | read_unlock(&xfrm_policy_afinfo_lock); |
| 1302 | return afinfo; |
| 1303 | } |
| 1304 | |
| 1305 | static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo) |
| 1306 | { |
| 1307 | if (unlikely(afinfo == NULL)) |
| 1308 | return; |
| 1309 | read_unlock(&afinfo->lock); |
| 1310 | } |
| 1311 | |
| 1312 | static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr) |
| 1313 | { |
| 1314 | switch (event) { |
| 1315 | case NETDEV_DOWN: |
| 1316 | xfrm_flush_bundles(); |
| 1317 | } |
| 1318 | return NOTIFY_DONE; |
| 1319 | } |
| 1320 | |
| 1321 | static struct notifier_block xfrm_dev_notifier = { |
| 1322 | xfrm_dev_event, |
| 1323 | NULL, |
| 1324 | 0 |
| 1325 | }; |
| 1326 | |
| 1327 | static void __init xfrm_policy_init(void) |
| 1328 | { |
| 1329 | xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", |
| 1330 | sizeof(struct xfrm_dst), |
| 1331 | 0, SLAB_HWCACHE_ALIGN, |
| 1332 | NULL, NULL); |
| 1333 | if (!xfrm_dst_cache) |
| 1334 | panic("XFRM: failed to allocate xfrm_dst_cache\n"); |
| 1335 | |
| 1336 | INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task, NULL); |
| 1337 | register_netdevice_notifier(&xfrm_dev_notifier); |
| 1338 | } |
| 1339 | |
| 1340 | void __init xfrm_init(void) |
| 1341 | { |
| 1342 | xfrm_state_init(); |
| 1343 | xfrm_policy_init(); |
| 1344 | xfrm_input_init(); |
| 1345 | } |
| 1346 | |