Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
| 3 | * operating system. INET is implemented using the BSD Socket |
| 4 | * interface as the means of communication with the user level. |
| 5 | * |
| 6 | * IPv4 FIB: lookup engine and maintenance routines. |
| 7 | * |
| 8 | * Version: $Id: fib_hash.c,v 1.13 2001/10/31 21:55:54 davem Exp $ |
| 9 | * |
| 10 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License |
| 14 | * as published by the Free Software Foundation; either version |
| 15 | * 2 of the License, or (at your option) any later version. |
| 16 | */ |
| 17 | |
| 18 | #include <linux/config.h> |
| 19 | #include <asm/uaccess.h> |
| 20 | #include <asm/system.h> |
| 21 | #include <linux/bitops.h> |
| 22 | #include <linux/types.h> |
| 23 | #include <linux/kernel.h> |
| 24 | #include <linux/sched.h> |
| 25 | #include <linux/mm.h> |
| 26 | #include <linux/string.h> |
| 27 | #include <linux/socket.h> |
| 28 | #include <linux/sockios.h> |
| 29 | #include <linux/errno.h> |
| 30 | #include <linux/in.h> |
| 31 | #include <linux/inet.h> |
| 32 | #include <linux/netdevice.h> |
| 33 | #include <linux/if_arp.h> |
| 34 | #include <linux/proc_fs.h> |
| 35 | #include <linux/skbuff.h> |
| 36 | #include <linux/netlink.h> |
| 37 | #include <linux/init.h> |
| 38 | |
| 39 | #include <net/ip.h> |
| 40 | #include <net/protocol.h> |
| 41 | #include <net/route.h> |
| 42 | #include <net/tcp.h> |
| 43 | #include <net/sock.h> |
| 44 | #include <net/ip_fib.h> |
| 45 | |
| 46 | #include "fib_lookup.h" |
| 47 | |
| 48 | static kmem_cache_t *fn_hash_kmem; |
| 49 | static kmem_cache_t *fn_alias_kmem; |
| 50 | |
| 51 | struct fib_node { |
| 52 | struct hlist_node fn_hash; |
| 53 | struct list_head fn_alias; |
| 54 | u32 fn_key; |
| 55 | }; |
| 56 | |
| 57 | struct fn_zone { |
| 58 | struct fn_zone *fz_next; /* Next not empty zone */ |
| 59 | struct hlist_head *fz_hash; /* Hash table pointer */ |
| 60 | int fz_nent; /* Number of entries */ |
| 61 | |
| 62 | int fz_divisor; /* Hash divisor */ |
| 63 | u32 fz_hashmask; /* (fz_divisor - 1) */ |
| 64 | #define FZ_HASHMASK(fz) ((fz)->fz_hashmask) |
| 65 | |
| 66 | int fz_order; /* Zone order */ |
| 67 | u32 fz_mask; |
| 68 | #define FZ_MASK(fz) ((fz)->fz_mask) |
| 69 | }; |
| 70 | |
| 71 | /* NOTE. On fast computers evaluation of fz_hashmask and fz_mask |
| 72 | * can be cheaper than memory lookup, so that FZ_* macros are used. |
| 73 | */ |
| 74 | |
| 75 | struct fn_hash { |
| 76 | struct fn_zone *fn_zones[33]; |
| 77 | struct fn_zone *fn_zone_list; |
| 78 | }; |
| 79 | |
| 80 | static inline u32 fn_hash(u32 key, struct fn_zone *fz) |
| 81 | { |
| 82 | u32 h = ntohl(key)>>(32 - fz->fz_order); |
| 83 | h ^= (h>>20); |
| 84 | h ^= (h>>10); |
| 85 | h ^= (h>>5); |
| 86 | h &= FZ_HASHMASK(fz); |
| 87 | return h; |
| 88 | } |
| 89 | |
| 90 | static inline u32 fz_key(u32 dst, struct fn_zone *fz) |
| 91 | { |
| 92 | return dst & FZ_MASK(fz); |
| 93 | } |
| 94 | |
| 95 | static DEFINE_RWLOCK(fib_hash_lock); |
| 96 | static unsigned int fib_hash_genid; |
| 97 | |
| 98 | #define FZ_MAX_DIVISOR ((PAGE_SIZE<<MAX_ORDER) / sizeof(struct hlist_head)) |
| 99 | |
| 100 | static struct hlist_head *fz_hash_alloc(int divisor) |
| 101 | { |
| 102 | unsigned long size = divisor * sizeof(struct hlist_head); |
| 103 | |
| 104 | if (size <= PAGE_SIZE) { |
| 105 | return kmalloc(size, GFP_KERNEL); |
| 106 | } else { |
| 107 | return (struct hlist_head *) |
| 108 | __get_free_pages(GFP_KERNEL, get_order(size)); |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | /* The fib hash lock must be held when this is called. */ |
| 113 | static inline void fn_rebuild_zone(struct fn_zone *fz, |
| 114 | struct hlist_head *old_ht, |
| 115 | int old_divisor) |
| 116 | { |
| 117 | int i; |
| 118 | |
| 119 | for (i = 0; i < old_divisor; i++) { |
| 120 | struct hlist_node *node, *n; |
| 121 | struct fib_node *f; |
| 122 | |
| 123 | hlist_for_each_entry_safe(f, node, n, &old_ht[i], fn_hash) { |
| 124 | struct hlist_head *new_head; |
| 125 | |
| 126 | hlist_del(&f->fn_hash); |
| 127 | |
| 128 | new_head = &fz->fz_hash[fn_hash(f->fn_key, fz)]; |
| 129 | hlist_add_head(&f->fn_hash, new_head); |
| 130 | } |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | static void fz_hash_free(struct hlist_head *hash, int divisor) |
| 135 | { |
| 136 | unsigned long size = divisor * sizeof(struct hlist_head); |
| 137 | |
| 138 | if (size <= PAGE_SIZE) |
| 139 | kfree(hash); |
| 140 | else |
| 141 | free_pages((unsigned long)hash, get_order(size)); |
| 142 | } |
| 143 | |
| 144 | static void fn_rehash_zone(struct fn_zone *fz) |
| 145 | { |
| 146 | struct hlist_head *ht, *old_ht; |
| 147 | int old_divisor, new_divisor; |
| 148 | u32 new_hashmask; |
| 149 | |
| 150 | old_divisor = fz->fz_divisor; |
| 151 | |
| 152 | switch (old_divisor) { |
| 153 | case 16: |
| 154 | new_divisor = 256; |
| 155 | break; |
| 156 | case 256: |
| 157 | new_divisor = 1024; |
| 158 | break; |
| 159 | default: |
| 160 | if ((old_divisor << 1) > FZ_MAX_DIVISOR) { |
| 161 | printk(KERN_CRIT "route.c: bad divisor %d!\n", old_divisor); |
| 162 | return; |
| 163 | } |
| 164 | new_divisor = (old_divisor << 1); |
| 165 | break; |
| 166 | } |
| 167 | |
| 168 | new_hashmask = (new_divisor - 1); |
| 169 | |
| 170 | #if RT_CACHE_DEBUG >= 2 |
| 171 | printk("fn_rehash_zone: hash for zone %d grows from %d\n", fz->fz_order, old_divisor); |
| 172 | #endif |
| 173 | |
| 174 | ht = fz_hash_alloc(new_divisor); |
| 175 | |
| 176 | if (ht) { |
| 177 | memset(ht, 0, new_divisor * sizeof(struct hlist_head)); |
| 178 | |
| 179 | write_lock_bh(&fib_hash_lock); |
| 180 | old_ht = fz->fz_hash; |
| 181 | fz->fz_hash = ht; |
| 182 | fz->fz_hashmask = new_hashmask; |
| 183 | fz->fz_divisor = new_divisor; |
| 184 | fn_rebuild_zone(fz, old_ht, old_divisor); |
| 185 | fib_hash_genid++; |
| 186 | write_unlock_bh(&fib_hash_lock); |
| 187 | |
| 188 | fz_hash_free(old_ht, old_divisor); |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | static inline void fn_free_node(struct fib_node * f) |
| 193 | { |
| 194 | kmem_cache_free(fn_hash_kmem, f); |
| 195 | } |
| 196 | |
| 197 | static inline void fn_free_alias(struct fib_alias *fa) |
| 198 | { |
| 199 | fib_release_info(fa->fa_info); |
| 200 | kmem_cache_free(fn_alias_kmem, fa); |
| 201 | } |
| 202 | |
| 203 | static struct fn_zone * |
| 204 | fn_new_zone(struct fn_hash *table, int z) |
| 205 | { |
| 206 | int i; |
| 207 | struct fn_zone *fz = kmalloc(sizeof(struct fn_zone), GFP_KERNEL); |
| 208 | if (!fz) |
| 209 | return NULL; |
| 210 | |
| 211 | memset(fz, 0, sizeof(struct fn_zone)); |
| 212 | if (z) { |
| 213 | fz->fz_divisor = 16; |
| 214 | } else { |
| 215 | fz->fz_divisor = 1; |
| 216 | } |
| 217 | fz->fz_hashmask = (fz->fz_divisor - 1); |
| 218 | fz->fz_hash = fz_hash_alloc(fz->fz_divisor); |
| 219 | if (!fz->fz_hash) { |
| 220 | kfree(fz); |
| 221 | return NULL; |
| 222 | } |
| 223 | memset(fz->fz_hash, 0, fz->fz_divisor * sizeof(struct hlist_head *)); |
| 224 | fz->fz_order = z; |
| 225 | fz->fz_mask = inet_make_mask(z); |
| 226 | |
| 227 | /* Find the first not empty zone with more specific mask */ |
| 228 | for (i=z+1; i<=32; i++) |
| 229 | if (table->fn_zones[i]) |
| 230 | break; |
| 231 | write_lock_bh(&fib_hash_lock); |
| 232 | if (i>32) { |
| 233 | /* No more specific masks, we are the first. */ |
| 234 | fz->fz_next = table->fn_zone_list; |
| 235 | table->fn_zone_list = fz; |
| 236 | } else { |
| 237 | fz->fz_next = table->fn_zones[i]->fz_next; |
| 238 | table->fn_zones[i]->fz_next = fz; |
| 239 | } |
| 240 | table->fn_zones[z] = fz; |
| 241 | fib_hash_genid++; |
| 242 | write_unlock_bh(&fib_hash_lock); |
| 243 | return fz; |
| 244 | } |
| 245 | |
| 246 | static int |
| 247 | fn_hash_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res) |
| 248 | { |
| 249 | int err; |
| 250 | struct fn_zone *fz; |
| 251 | struct fn_hash *t = (struct fn_hash*)tb->tb_data; |
| 252 | |
| 253 | read_lock(&fib_hash_lock); |
| 254 | for (fz = t->fn_zone_list; fz; fz = fz->fz_next) { |
| 255 | struct hlist_head *head; |
| 256 | struct hlist_node *node; |
| 257 | struct fib_node *f; |
| 258 | u32 k = fz_key(flp->fl4_dst, fz); |
| 259 | |
| 260 | head = &fz->fz_hash[fn_hash(k, fz)]; |
| 261 | hlist_for_each_entry(f, node, head, fn_hash) { |
| 262 | if (f->fn_key != k) |
| 263 | continue; |
| 264 | |
| 265 | err = fib_semantic_match(&f->fn_alias, |
| 266 | flp, res, |
| 267 | f->fn_key, fz->fz_mask, |
| 268 | fz->fz_order); |
| 269 | if (err <= 0) |
| 270 | goto out; |
| 271 | } |
| 272 | } |
| 273 | err = 1; |
| 274 | out: |
| 275 | read_unlock(&fib_hash_lock); |
| 276 | return err; |
| 277 | } |
| 278 | |
| 279 | static int fn_hash_last_dflt=-1; |
| 280 | |
| 281 | static void |
| 282 | fn_hash_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res) |
| 283 | { |
| 284 | int order, last_idx; |
| 285 | struct hlist_node *node; |
| 286 | struct fib_node *f; |
| 287 | struct fib_info *fi = NULL; |
| 288 | struct fib_info *last_resort; |
| 289 | struct fn_hash *t = (struct fn_hash*)tb->tb_data; |
| 290 | struct fn_zone *fz = t->fn_zones[0]; |
| 291 | |
| 292 | if (fz == NULL) |
| 293 | return; |
| 294 | |
| 295 | last_idx = -1; |
| 296 | last_resort = NULL; |
| 297 | order = -1; |
| 298 | |
| 299 | read_lock(&fib_hash_lock); |
| 300 | hlist_for_each_entry(f, node, &fz->fz_hash[0], fn_hash) { |
| 301 | struct fib_alias *fa; |
| 302 | |
| 303 | list_for_each_entry(fa, &f->fn_alias, fa_list) { |
| 304 | struct fib_info *next_fi = fa->fa_info; |
| 305 | |
| 306 | if (fa->fa_scope != res->scope || |
| 307 | fa->fa_type != RTN_UNICAST) |
| 308 | continue; |
| 309 | |
| 310 | if (next_fi->fib_priority > res->fi->fib_priority) |
| 311 | break; |
| 312 | if (!next_fi->fib_nh[0].nh_gw || |
| 313 | next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK) |
| 314 | continue; |
| 315 | fa->fa_state |= FA_S_ACCESSED; |
| 316 | |
| 317 | if (fi == NULL) { |
| 318 | if (next_fi != res->fi) |
| 319 | break; |
| 320 | } else if (!fib_detect_death(fi, order, &last_resort, |
| 321 | &last_idx, &fn_hash_last_dflt)) { |
| 322 | if (res->fi) |
| 323 | fib_info_put(res->fi); |
| 324 | res->fi = fi; |
| 325 | atomic_inc(&fi->fib_clntref); |
| 326 | fn_hash_last_dflt = order; |
| 327 | goto out; |
| 328 | } |
| 329 | fi = next_fi; |
| 330 | order++; |
| 331 | } |
| 332 | } |
| 333 | |
| 334 | if (order <= 0 || fi == NULL) { |
| 335 | fn_hash_last_dflt = -1; |
| 336 | goto out; |
| 337 | } |
| 338 | |
| 339 | if (!fib_detect_death(fi, order, &last_resort, &last_idx, &fn_hash_last_dflt)) { |
| 340 | if (res->fi) |
| 341 | fib_info_put(res->fi); |
| 342 | res->fi = fi; |
| 343 | atomic_inc(&fi->fib_clntref); |
| 344 | fn_hash_last_dflt = order; |
| 345 | goto out; |
| 346 | } |
| 347 | |
| 348 | if (last_idx >= 0) { |
| 349 | if (res->fi) |
| 350 | fib_info_put(res->fi); |
| 351 | res->fi = last_resort; |
| 352 | if (last_resort) |
| 353 | atomic_inc(&last_resort->fib_clntref); |
| 354 | } |
| 355 | fn_hash_last_dflt = last_idx; |
| 356 | out: |
| 357 | read_unlock(&fib_hash_lock); |
| 358 | } |
| 359 | |
| 360 | /* Insert node F to FZ. */ |
| 361 | static inline void fib_insert_node(struct fn_zone *fz, struct fib_node *f) |
| 362 | { |
| 363 | struct hlist_head *head = &fz->fz_hash[fn_hash(f->fn_key, fz)]; |
| 364 | |
| 365 | hlist_add_head(&f->fn_hash, head); |
| 366 | } |
| 367 | |
| 368 | /* Return the node in FZ matching KEY. */ |
| 369 | static struct fib_node *fib_find_node(struct fn_zone *fz, u32 key) |
| 370 | { |
| 371 | struct hlist_head *head = &fz->fz_hash[fn_hash(key, fz)]; |
| 372 | struct hlist_node *node; |
| 373 | struct fib_node *f; |
| 374 | |
| 375 | hlist_for_each_entry(f, node, head, fn_hash) { |
| 376 | if (f->fn_key == key) |
| 377 | return f; |
| 378 | } |
| 379 | |
| 380 | return NULL; |
| 381 | } |
| 382 | |
| 383 | static int |
| 384 | fn_hash_insert(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta, |
| 385 | struct nlmsghdr *n, struct netlink_skb_parms *req) |
| 386 | { |
| 387 | struct fn_hash *table = (struct fn_hash *) tb->tb_data; |
| 388 | struct fib_node *new_f, *f; |
| 389 | struct fib_alias *fa, *new_fa; |
| 390 | struct fn_zone *fz; |
| 391 | struct fib_info *fi; |
| 392 | int z = r->rtm_dst_len; |
| 393 | int type = r->rtm_type; |
| 394 | u8 tos = r->rtm_tos; |
| 395 | u32 key; |
| 396 | int err; |
| 397 | |
| 398 | if (z > 32) |
| 399 | return -EINVAL; |
| 400 | fz = table->fn_zones[z]; |
| 401 | if (!fz && !(fz = fn_new_zone(table, z))) |
| 402 | return -ENOBUFS; |
| 403 | |
| 404 | key = 0; |
| 405 | if (rta->rta_dst) { |
| 406 | u32 dst; |
| 407 | memcpy(&dst, rta->rta_dst, 4); |
| 408 | if (dst & ~FZ_MASK(fz)) |
| 409 | return -EINVAL; |
| 410 | key = fz_key(dst, fz); |
| 411 | } |
| 412 | |
| 413 | if ((fi = fib_create_info(r, rta, n, &err)) == NULL) |
| 414 | return err; |
| 415 | |
| 416 | if (fz->fz_nent > (fz->fz_divisor<<1) && |
| 417 | fz->fz_divisor < FZ_MAX_DIVISOR && |
| 418 | (z==32 || (1<<z) > fz->fz_divisor)) |
| 419 | fn_rehash_zone(fz); |
| 420 | |
| 421 | f = fib_find_node(fz, key); |
| 422 | |
| 423 | if (!f) |
| 424 | fa = NULL; |
| 425 | else |
| 426 | fa = fib_find_alias(&f->fn_alias, tos, fi->fib_priority); |
| 427 | |
| 428 | /* Now fa, if non-NULL, points to the first fib alias |
| 429 | * with the same keys [prefix,tos,priority], if such key already |
| 430 | * exists or to the node before which we will insert new one. |
| 431 | * |
| 432 | * If fa is NULL, we will need to allocate a new one and |
| 433 | * insert to the head of f. |
| 434 | * |
| 435 | * If f is NULL, no fib node matched the destination key |
| 436 | * and we need to allocate a new one of those as well. |
| 437 | */ |
| 438 | |
| 439 | if (fa && fa->fa_tos == tos && |
| 440 | fa->fa_info->fib_priority == fi->fib_priority) { |
| 441 | struct fib_alias *fa_orig; |
| 442 | |
| 443 | err = -EEXIST; |
| 444 | if (n->nlmsg_flags & NLM_F_EXCL) |
| 445 | goto out; |
| 446 | |
| 447 | if (n->nlmsg_flags & NLM_F_REPLACE) { |
| 448 | struct fib_info *fi_drop; |
| 449 | u8 state; |
| 450 | |
| 451 | write_lock_bh(&fib_hash_lock); |
| 452 | fi_drop = fa->fa_info; |
| 453 | fa->fa_info = fi; |
| 454 | fa->fa_type = type; |
| 455 | fa->fa_scope = r->rtm_scope; |
| 456 | state = fa->fa_state; |
| 457 | fa->fa_state &= ~FA_S_ACCESSED; |
| 458 | fib_hash_genid++; |
| 459 | write_unlock_bh(&fib_hash_lock); |
| 460 | |
| 461 | fib_release_info(fi_drop); |
| 462 | if (state & FA_S_ACCESSED) |
| 463 | rt_cache_flush(-1); |
| 464 | return 0; |
| 465 | } |
| 466 | |
| 467 | /* Error if we find a perfect match which |
| 468 | * uses the same scope, type, and nexthop |
| 469 | * information. |
| 470 | */ |
| 471 | fa_orig = fa; |
| 472 | fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list); |
| 473 | list_for_each_entry_continue(fa, &f->fn_alias, fa_list) { |
| 474 | if (fa->fa_tos != tos) |
| 475 | break; |
| 476 | if (fa->fa_info->fib_priority != fi->fib_priority) |
| 477 | break; |
| 478 | if (fa->fa_type == type && |
| 479 | fa->fa_scope == r->rtm_scope && |
| 480 | fa->fa_info == fi) |
| 481 | goto out; |
| 482 | } |
| 483 | if (!(n->nlmsg_flags & NLM_F_APPEND)) |
| 484 | fa = fa_orig; |
| 485 | } |
| 486 | |
| 487 | err = -ENOENT; |
| 488 | if (!(n->nlmsg_flags&NLM_F_CREATE)) |
| 489 | goto out; |
| 490 | |
| 491 | err = -ENOBUFS; |
| 492 | new_fa = kmem_cache_alloc(fn_alias_kmem, SLAB_KERNEL); |
| 493 | if (new_fa == NULL) |
| 494 | goto out; |
| 495 | |
| 496 | new_f = NULL; |
| 497 | if (!f) { |
| 498 | new_f = kmem_cache_alloc(fn_hash_kmem, SLAB_KERNEL); |
| 499 | if (new_f == NULL) |
| 500 | goto out_free_new_fa; |
| 501 | |
| 502 | INIT_HLIST_NODE(&new_f->fn_hash); |
| 503 | INIT_LIST_HEAD(&new_f->fn_alias); |
| 504 | new_f->fn_key = key; |
| 505 | f = new_f; |
| 506 | } |
| 507 | |
| 508 | new_fa->fa_info = fi; |
| 509 | new_fa->fa_tos = tos; |
| 510 | new_fa->fa_type = type; |
| 511 | new_fa->fa_scope = r->rtm_scope; |
| 512 | new_fa->fa_state = 0; |
| 513 | |
| 514 | /* |
| 515 | * Insert new entry to the list. |
| 516 | */ |
| 517 | |
| 518 | write_lock_bh(&fib_hash_lock); |
| 519 | if (new_f) |
| 520 | fib_insert_node(fz, new_f); |
| 521 | list_add_tail(&new_fa->fa_list, |
| 522 | (fa ? &fa->fa_list : &f->fn_alias)); |
| 523 | fib_hash_genid++; |
| 524 | write_unlock_bh(&fib_hash_lock); |
| 525 | |
| 526 | if (new_f) |
| 527 | fz->fz_nent++; |
| 528 | rt_cache_flush(-1); |
| 529 | |
| 530 | rtmsg_fib(RTM_NEWROUTE, key, new_fa, z, tb->tb_id, n, req); |
| 531 | return 0; |
| 532 | |
| 533 | out_free_new_fa: |
| 534 | kmem_cache_free(fn_alias_kmem, new_fa); |
| 535 | out: |
| 536 | fib_release_info(fi); |
| 537 | return err; |
| 538 | } |
| 539 | |
| 540 | |
| 541 | static int |
| 542 | fn_hash_delete(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta, |
| 543 | struct nlmsghdr *n, struct netlink_skb_parms *req) |
| 544 | { |
| 545 | struct fn_hash *table = (struct fn_hash*)tb->tb_data; |
| 546 | struct fib_node *f; |
| 547 | struct fib_alias *fa, *fa_to_delete; |
| 548 | int z = r->rtm_dst_len; |
| 549 | struct fn_zone *fz; |
| 550 | u32 key; |
| 551 | u8 tos = r->rtm_tos; |
| 552 | |
| 553 | if (z > 32) |
| 554 | return -EINVAL; |
| 555 | if ((fz = table->fn_zones[z]) == NULL) |
| 556 | return -ESRCH; |
| 557 | |
| 558 | key = 0; |
| 559 | if (rta->rta_dst) { |
| 560 | u32 dst; |
| 561 | memcpy(&dst, rta->rta_dst, 4); |
| 562 | if (dst & ~FZ_MASK(fz)) |
| 563 | return -EINVAL; |
| 564 | key = fz_key(dst, fz); |
| 565 | } |
| 566 | |
| 567 | f = fib_find_node(fz, key); |
| 568 | |
| 569 | if (!f) |
| 570 | fa = NULL; |
| 571 | else |
| 572 | fa = fib_find_alias(&f->fn_alias, tos, 0); |
| 573 | if (!fa) |
| 574 | return -ESRCH; |
| 575 | |
| 576 | fa_to_delete = NULL; |
| 577 | fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list); |
| 578 | list_for_each_entry_continue(fa, &f->fn_alias, fa_list) { |
| 579 | struct fib_info *fi = fa->fa_info; |
| 580 | |
| 581 | if (fa->fa_tos != tos) |
| 582 | break; |
| 583 | |
| 584 | if ((!r->rtm_type || |
| 585 | fa->fa_type == r->rtm_type) && |
| 586 | (r->rtm_scope == RT_SCOPE_NOWHERE || |
| 587 | fa->fa_scope == r->rtm_scope) && |
| 588 | (!r->rtm_protocol || |
| 589 | fi->fib_protocol == r->rtm_protocol) && |
| 590 | fib_nh_match(r, n, rta, fi) == 0) { |
| 591 | fa_to_delete = fa; |
| 592 | break; |
| 593 | } |
| 594 | } |
| 595 | |
| 596 | if (fa_to_delete) { |
| 597 | int kill_fn; |
| 598 | |
| 599 | fa = fa_to_delete; |
| 600 | rtmsg_fib(RTM_DELROUTE, key, fa, z, tb->tb_id, n, req); |
| 601 | |
| 602 | kill_fn = 0; |
| 603 | write_lock_bh(&fib_hash_lock); |
| 604 | list_del(&fa->fa_list); |
| 605 | if (list_empty(&f->fn_alias)) { |
| 606 | hlist_del(&f->fn_hash); |
| 607 | kill_fn = 1; |
| 608 | } |
| 609 | fib_hash_genid++; |
| 610 | write_unlock_bh(&fib_hash_lock); |
| 611 | |
| 612 | if (fa->fa_state & FA_S_ACCESSED) |
| 613 | rt_cache_flush(-1); |
| 614 | fn_free_alias(fa); |
| 615 | if (kill_fn) { |
| 616 | fn_free_node(f); |
| 617 | fz->fz_nent--; |
| 618 | } |
| 619 | |
| 620 | return 0; |
| 621 | } |
| 622 | return -ESRCH; |
| 623 | } |
| 624 | |
| 625 | static int fn_flush_list(struct fn_zone *fz, int idx) |
| 626 | { |
| 627 | struct hlist_head *head = &fz->fz_hash[idx]; |
| 628 | struct hlist_node *node, *n; |
| 629 | struct fib_node *f; |
| 630 | int found = 0; |
| 631 | |
| 632 | hlist_for_each_entry_safe(f, node, n, head, fn_hash) { |
| 633 | struct fib_alias *fa, *fa_node; |
| 634 | int kill_f; |
| 635 | |
| 636 | kill_f = 0; |
| 637 | list_for_each_entry_safe(fa, fa_node, &f->fn_alias, fa_list) { |
| 638 | struct fib_info *fi = fa->fa_info; |
| 639 | |
| 640 | if (fi && (fi->fib_flags&RTNH_F_DEAD)) { |
| 641 | write_lock_bh(&fib_hash_lock); |
| 642 | list_del(&fa->fa_list); |
| 643 | if (list_empty(&f->fn_alias)) { |
| 644 | hlist_del(&f->fn_hash); |
| 645 | kill_f = 1; |
| 646 | } |
| 647 | fib_hash_genid++; |
| 648 | write_unlock_bh(&fib_hash_lock); |
| 649 | |
| 650 | fn_free_alias(fa); |
| 651 | found++; |
| 652 | } |
| 653 | } |
| 654 | if (kill_f) { |
| 655 | fn_free_node(f); |
| 656 | fz->fz_nent--; |
| 657 | } |
| 658 | } |
| 659 | return found; |
| 660 | } |
| 661 | |
| 662 | static int fn_hash_flush(struct fib_table *tb) |
| 663 | { |
| 664 | struct fn_hash *table = (struct fn_hash *) tb->tb_data; |
| 665 | struct fn_zone *fz; |
| 666 | int found = 0; |
| 667 | |
| 668 | for (fz = table->fn_zone_list; fz; fz = fz->fz_next) { |
| 669 | int i; |
| 670 | |
| 671 | for (i = fz->fz_divisor - 1; i >= 0; i--) |
| 672 | found += fn_flush_list(fz, i); |
| 673 | } |
| 674 | return found; |
| 675 | } |
| 676 | |
| 677 | |
| 678 | static inline int |
| 679 | fn_hash_dump_bucket(struct sk_buff *skb, struct netlink_callback *cb, |
| 680 | struct fib_table *tb, |
| 681 | struct fn_zone *fz, |
| 682 | struct hlist_head *head) |
| 683 | { |
| 684 | struct hlist_node *node; |
| 685 | struct fib_node *f; |
| 686 | int i, s_i; |
| 687 | |
| 688 | s_i = cb->args[3]; |
| 689 | i = 0; |
| 690 | hlist_for_each_entry(f, node, head, fn_hash) { |
| 691 | struct fib_alias *fa; |
| 692 | |
| 693 | list_for_each_entry(fa, &f->fn_alias, fa_list) { |
| 694 | if (i < s_i) |
| 695 | goto next; |
| 696 | |
| 697 | if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid, |
| 698 | cb->nlh->nlmsg_seq, |
| 699 | RTM_NEWROUTE, |
| 700 | tb->tb_id, |
| 701 | fa->fa_type, |
| 702 | fa->fa_scope, |
| 703 | &f->fn_key, |
| 704 | fz->fz_order, |
| 705 | fa->fa_tos, |
Jamal Hadi Salim | b6544c0 | 2005-06-18 22:54:12 -0700 | [diff] [blame] | 706 | fa->fa_info, |
| 707 | NLM_F_MULTI) < 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | cb->args[3] = i; |
| 709 | return -1; |
| 710 | } |
| 711 | next: |
| 712 | i++; |
| 713 | } |
| 714 | } |
| 715 | cb->args[3] = i; |
| 716 | return skb->len; |
| 717 | } |
| 718 | |
| 719 | static inline int |
| 720 | fn_hash_dump_zone(struct sk_buff *skb, struct netlink_callback *cb, |
| 721 | struct fib_table *tb, |
| 722 | struct fn_zone *fz) |
| 723 | { |
| 724 | int h, s_h; |
| 725 | |
| 726 | s_h = cb->args[2]; |
| 727 | for (h=0; h < fz->fz_divisor; h++) { |
| 728 | if (h < s_h) continue; |
| 729 | if (h > s_h) |
| 730 | memset(&cb->args[3], 0, |
| 731 | sizeof(cb->args) - 3*sizeof(cb->args[0])); |
| 732 | if (fz->fz_hash == NULL || |
| 733 | hlist_empty(&fz->fz_hash[h])) |
| 734 | continue; |
| 735 | if (fn_hash_dump_bucket(skb, cb, tb, fz, &fz->fz_hash[h])<0) { |
| 736 | cb->args[2] = h; |
| 737 | return -1; |
| 738 | } |
| 739 | } |
| 740 | cb->args[2] = h; |
| 741 | return skb->len; |
| 742 | } |
| 743 | |
| 744 | static int fn_hash_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb) |
| 745 | { |
| 746 | int m, s_m; |
| 747 | struct fn_zone *fz; |
| 748 | struct fn_hash *table = (struct fn_hash*)tb->tb_data; |
| 749 | |
| 750 | s_m = cb->args[1]; |
| 751 | read_lock(&fib_hash_lock); |
| 752 | for (fz = table->fn_zone_list, m=0; fz; fz = fz->fz_next, m++) { |
| 753 | if (m < s_m) continue; |
| 754 | if (m > s_m) |
| 755 | memset(&cb->args[2], 0, |
| 756 | sizeof(cb->args) - 2*sizeof(cb->args[0])); |
| 757 | if (fn_hash_dump_zone(skb, cb, tb, fz) < 0) { |
| 758 | cb->args[1] = m; |
| 759 | read_unlock(&fib_hash_lock); |
| 760 | return -1; |
| 761 | } |
| 762 | } |
| 763 | read_unlock(&fib_hash_lock); |
| 764 | cb->args[1] = m; |
| 765 | return skb->len; |
| 766 | } |
| 767 | |
| 768 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
| 769 | struct fib_table * fib_hash_init(int id) |
| 770 | #else |
| 771 | struct fib_table * __init fib_hash_init(int id) |
| 772 | #endif |
| 773 | { |
| 774 | struct fib_table *tb; |
| 775 | |
| 776 | if (fn_hash_kmem == NULL) |
| 777 | fn_hash_kmem = kmem_cache_create("ip_fib_hash", |
| 778 | sizeof(struct fib_node), |
| 779 | 0, SLAB_HWCACHE_ALIGN, |
| 780 | NULL, NULL); |
| 781 | |
| 782 | if (fn_alias_kmem == NULL) |
| 783 | fn_alias_kmem = kmem_cache_create("ip_fib_alias", |
| 784 | sizeof(struct fib_alias), |
| 785 | 0, SLAB_HWCACHE_ALIGN, |
| 786 | NULL, NULL); |
| 787 | |
| 788 | tb = kmalloc(sizeof(struct fib_table) + sizeof(struct fn_hash), |
| 789 | GFP_KERNEL); |
| 790 | if (tb == NULL) |
| 791 | return NULL; |
| 792 | |
| 793 | tb->tb_id = id; |
| 794 | tb->tb_lookup = fn_hash_lookup; |
| 795 | tb->tb_insert = fn_hash_insert; |
| 796 | tb->tb_delete = fn_hash_delete; |
| 797 | tb->tb_flush = fn_hash_flush; |
| 798 | tb->tb_select_default = fn_hash_select_default; |
| 799 | tb->tb_dump = fn_hash_dump; |
| 800 | memset(tb->tb_data, 0, sizeof(struct fn_hash)); |
| 801 | return tb; |
| 802 | } |
| 803 | |
| 804 | /* ------------------------------------------------------------------------ */ |
| 805 | #ifdef CONFIG_PROC_FS |
| 806 | |
| 807 | struct fib_iter_state { |
| 808 | struct fn_zone *zone; |
| 809 | int bucket; |
| 810 | struct hlist_head *hash_head; |
| 811 | struct fib_node *fn; |
| 812 | struct fib_alias *fa; |
| 813 | loff_t pos; |
| 814 | unsigned int genid; |
| 815 | int valid; |
| 816 | }; |
| 817 | |
| 818 | static struct fib_alias *fib_get_first(struct seq_file *seq) |
| 819 | { |
| 820 | struct fib_iter_state *iter = seq->private; |
| 821 | struct fn_hash *table = (struct fn_hash *) ip_fib_main_table->tb_data; |
| 822 | |
| 823 | iter->bucket = 0; |
| 824 | iter->hash_head = NULL; |
| 825 | iter->fn = NULL; |
| 826 | iter->fa = NULL; |
| 827 | iter->pos = 0; |
| 828 | iter->genid = fib_hash_genid; |
| 829 | iter->valid = 1; |
| 830 | |
| 831 | for (iter->zone = table->fn_zone_list; iter->zone; |
| 832 | iter->zone = iter->zone->fz_next) { |
| 833 | int maxslot; |
| 834 | |
| 835 | if (!iter->zone->fz_nent) |
| 836 | continue; |
| 837 | |
| 838 | iter->hash_head = iter->zone->fz_hash; |
| 839 | maxslot = iter->zone->fz_divisor; |
| 840 | |
| 841 | for (iter->bucket = 0; iter->bucket < maxslot; |
| 842 | ++iter->bucket, ++iter->hash_head) { |
| 843 | struct hlist_node *node; |
| 844 | struct fib_node *fn; |
| 845 | |
| 846 | hlist_for_each_entry(fn,node,iter->hash_head,fn_hash) { |
| 847 | struct fib_alias *fa; |
| 848 | |
| 849 | list_for_each_entry(fa,&fn->fn_alias,fa_list) { |
| 850 | iter->fn = fn; |
| 851 | iter->fa = fa; |
| 852 | goto out; |
| 853 | } |
| 854 | } |
| 855 | } |
| 856 | } |
| 857 | out: |
| 858 | return iter->fa; |
| 859 | } |
| 860 | |
| 861 | static struct fib_alias *fib_get_next(struct seq_file *seq) |
| 862 | { |
| 863 | struct fib_iter_state *iter = seq->private; |
| 864 | struct fib_node *fn; |
| 865 | struct fib_alias *fa; |
| 866 | |
| 867 | /* Advance FA, if any. */ |
| 868 | fn = iter->fn; |
| 869 | fa = iter->fa; |
| 870 | if (fa) { |
| 871 | BUG_ON(!fn); |
| 872 | list_for_each_entry_continue(fa, &fn->fn_alias, fa_list) { |
| 873 | iter->fa = fa; |
| 874 | goto out; |
| 875 | } |
| 876 | } |
| 877 | |
| 878 | fa = iter->fa = NULL; |
| 879 | |
| 880 | /* Advance FN. */ |
| 881 | if (fn) { |
| 882 | struct hlist_node *node = &fn->fn_hash; |
| 883 | hlist_for_each_entry_continue(fn, node, fn_hash) { |
| 884 | iter->fn = fn; |
| 885 | |
| 886 | list_for_each_entry(fa, &fn->fn_alias, fa_list) { |
| 887 | iter->fa = fa; |
| 888 | goto out; |
| 889 | } |
| 890 | } |
| 891 | } |
| 892 | |
| 893 | fn = iter->fn = NULL; |
| 894 | |
| 895 | /* Advance hash chain. */ |
| 896 | if (!iter->zone) |
| 897 | goto out; |
| 898 | |
| 899 | for (;;) { |
| 900 | struct hlist_node *node; |
| 901 | int maxslot; |
| 902 | |
| 903 | maxslot = iter->zone->fz_divisor; |
| 904 | |
| 905 | while (++iter->bucket < maxslot) { |
| 906 | iter->hash_head++; |
| 907 | |
| 908 | hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) { |
| 909 | list_for_each_entry(fa, &fn->fn_alias, fa_list) { |
| 910 | iter->fn = fn; |
| 911 | iter->fa = fa; |
| 912 | goto out; |
| 913 | } |
| 914 | } |
| 915 | } |
| 916 | |
| 917 | iter->zone = iter->zone->fz_next; |
| 918 | |
| 919 | if (!iter->zone) |
| 920 | goto out; |
| 921 | |
| 922 | iter->bucket = 0; |
| 923 | iter->hash_head = iter->zone->fz_hash; |
| 924 | |
| 925 | hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) { |
| 926 | list_for_each_entry(fa, &fn->fn_alias, fa_list) { |
| 927 | iter->fn = fn; |
| 928 | iter->fa = fa; |
| 929 | goto out; |
| 930 | } |
| 931 | } |
| 932 | } |
| 933 | out: |
| 934 | iter->pos++; |
| 935 | return fa; |
| 936 | } |
| 937 | |
| 938 | static struct fib_alias *fib_get_idx(struct seq_file *seq, loff_t pos) |
| 939 | { |
| 940 | struct fib_iter_state *iter = seq->private; |
| 941 | struct fib_alias *fa; |
| 942 | |
| 943 | if (iter->valid && pos >= iter->pos && iter->genid == fib_hash_genid) { |
| 944 | fa = iter->fa; |
| 945 | pos -= iter->pos; |
| 946 | } else |
| 947 | fa = fib_get_first(seq); |
| 948 | |
| 949 | if (fa) |
| 950 | while (pos && (fa = fib_get_next(seq))) |
| 951 | --pos; |
| 952 | return pos ? NULL : fa; |
| 953 | } |
| 954 | |
| 955 | static void *fib_seq_start(struct seq_file *seq, loff_t *pos) |
| 956 | { |
| 957 | void *v = NULL; |
| 958 | |
| 959 | read_lock(&fib_hash_lock); |
| 960 | if (ip_fib_main_table) |
| 961 | v = *pos ? fib_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; |
| 962 | return v; |
| 963 | } |
| 964 | |
| 965 | static void *fib_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 966 | { |
| 967 | ++*pos; |
| 968 | return v == SEQ_START_TOKEN ? fib_get_first(seq) : fib_get_next(seq); |
| 969 | } |
| 970 | |
| 971 | static void fib_seq_stop(struct seq_file *seq, void *v) |
| 972 | { |
| 973 | read_unlock(&fib_hash_lock); |
| 974 | } |
| 975 | |
| 976 | static unsigned fib_flag_trans(int type, u32 mask, struct fib_info *fi) |
| 977 | { |
| 978 | static unsigned type2flags[RTN_MAX + 1] = { |
| 979 | [7] = RTF_REJECT, [8] = RTF_REJECT, |
| 980 | }; |
| 981 | unsigned flags = type2flags[type]; |
| 982 | |
| 983 | if (fi && fi->fib_nh->nh_gw) |
| 984 | flags |= RTF_GATEWAY; |
| 985 | if (mask == 0xFFFFFFFF) |
| 986 | flags |= RTF_HOST; |
| 987 | flags |= RTF_UP; |
| 988 | return flags; |
| 989 | } |
| 990 | |
| 991 | /* |
| 992 | * This outputs /proc/net/route. |
| 993 | * |
| 994 | * It always works in backward compatibility mode. |
| 995 | * The format of the file is not supposed to be changed. |
| 996 | */ |
| 997 | static int fib_seq_show(struct seq_file *seq, void *v) |
| 998 | { |
| 999 | struct fib_iter_state *iter; |
| 1000 | char bf[128]; |
| 1001 | u32 prefix, mask; |
| 1002 | unsigned flags; |
| 1003 | struct fib_node *f; |
| 1004 | struct fib_alias *fa; |
| 1005 | struct fib_info *fi; |
| 1006 | |
| 1007 | if (v == SEQ_START_TOKEN) { |
| 1008 | seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway " |
| 1009 | "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU" |
| 1010 | "\tWindow\tIRTT"); |
| 1011 | goto out; |
| 1012 | } |
| 1013 | |
| 1014 | iter = seq->private; |
| 1015 | f = iter->fn; |
| 1016 | fa = iter->fa; |
| 1017 | fi = fa->fa_info; |
| 1018 | prefix = f->fn_key; |
| 1019 | mask = FZ_MASK(iter->zone); |
| 1020 | flags = fib_flag_trans(fa->fa_type, mask, fi); |
| 1021 | if (fi) |
| 1022 | snprintf(bf, sizeof(bf), |
| 1023 | "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u", |
| 1024 | fi->fib_dev ? fi->fib_dev->name : "*", prefix, |
| 1025 | fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority, |
| 1026 | mask, (fi->fib_advmss ? fi->fib_advmss + 40 : 0), |
| 1027 | fi->fib_window, |
| 1028 | fi->fib_rtt >> 3); |
| 1029 | else |
| 1030 | snprintf(bf, sizeof(bf), |
| 1031 | "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u", |
| 1032 | prefix, 0, flags, 0, 0, 0, mask, 0, 0, 0); |
| 1033 | seq_printf(seq, "%-127s\n", bf); |
| 1034 | out: |
| 1035 | return 0; |
| 1036 | } |
| 1037 | |
| 1038 | static struct seq_operations fib_seq_ops = { |
| 1039 | .start = fib_seq_start, |
| 1040 | .next = fib_seq_next, |
| 1041 | .stop = fib_seq_stop, |
| 1042 | .show = fib_seq_show, |
| 1043 | }; |
| 1044 | |
| 1045 | static int fib_seq_open(struct inode *inode, struct file *file) |
| 1046 | { |
| 1047 | struct seq_file *seq; |
| 1048 | int rc = -ENOMEM; |
| 1049 | struct fib_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL); |
| 1050 | |
| 1051 | if (!s) |
| 1052 | goto out; |
| 1053 | |
| 1054 | rc = seq_open(file, &fib_seq_ops); |
| 1055 | if (rc) |
| 1056 | goto out_kfree; |
| 1057 | |
| 1058 | seq = file->private_data; |
| 1059 | seq->private = s; |
| 1060 | memset(s, 0, sizeof(*s)); |
| 1061 | out: |
| 1062 | return rc; |
| 1063 | out_kfree: |
| 1064 | kfree(s); |
| 1065 | goto out; |
| 1066 | } |
| 1067 | |
| 1068 | static struct file_operations fib_seq_fops = { |
| 1069 | .owner = THIS_MODULE, |
| 1070 | .open = fib_seq_open, |
| 1071 | .read = seq_read, |
| 1072 | .llseek = seq_lseek, |
| 1073 | .release = seq_release_private, |
| 1074 | }; |
| 1075 | |
| 1076 | int __init fib_proc_init(void) |
| 1077 | { |
| 1078 | if (!proc_net_fops_create("route", S_IRUGO, &fib_seq_fops)) |
| 1079 | return -ENOMEM; |
| 1080 | return 0; |
| 1081 | } |
| 1082 | |
| 1083 | void __init fib_proc_exit(void) |
| 1084 | { |
| 1085 | proc_net_remove("route"); |
| 1086 | } |
| 1087 | #endif /* CONFIG_PROC_FS */ |