1/* 2 * DECnet An implementation of the DECnet protocol suite for the LINUX 3 * operating system. DECnet is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * DECnet Routing Forwarding Information Base (Routing Tables) 7 * 8 * Author: Steve Whitehouse <SteveW@ACM.org> 9 * Mostly copied from the IPv4 routing code 10 * 11 * 12 * Changes: 13 * 14 */ 15#include <linux/string.h> 16#include <linux/net.h> 17#include <linux/socket.h> 18#include <linux/slab.h> 19#include <linux/sockios.h> 20#include <linux/init.h> 21#include <linux/skbuff.h> 22#include <linux/rtnetlink.h> 23#include <linux/proc_fs.h> 24#include <linux/netdevice.h> 25#include <linux/timer.h> 26#include <linux/spinlock.h> 27#include <linux/atomic.h> 28#include <asm/uaccess.h> 29#include <linux/route.h> /* RTF_xxx */ 30#include <net/neighbour.h> 31#include <net/netlink.h> 32#include <net/tcp.h> 33#include <net/dst.h> 34#include <net/flow.h> 35#include <net/fib_rules.h> 36#include <net/dn.h> 37#include <net/dn_route.h> 38#include <net/dn_fib.h> 39#include <net/dn_neigh.h> 40#include <net/dn_dev.h> 41 42struct dn_zone 43{ 44 struct dn_zone *dz_next; 45 struct dn_fib_node **dz_hash; 46 int dz_nent; 47 int dz_divisor; 48 u32 dz_hashmask; 49#define DZ_HASHMASK(dz) ((dz)->dz_hashmask) 50 int dz_order; 51 __le16 dz_mask; 52#define DZ_MASK(dz) ((dz)->dz_mask) 53}; 54 55struct dn_hash 56{ 57 struct dn_zone *dh_zones[17]; 58 struct dn_zone *dh_zone_list; 59}; 60 61#define dz_key_0(key) ((key).datum = 0) 62 63#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\ 64 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++) 65 66#define endfor_nexthops(fi) } 67 68#define DN_MAX_DIVISOR 1024 69#define DN_S_ZOMBIE 1 70#define DN_S_ACCESSED 2 71 72#define DN_FIB_SCAN(f, fp) \ 73for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next) 74 75#define DN_FIB_SCAN_KEY(f, fp, key) \ 76for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next) 77 78#define RT_TABLE_MIN 1 79#define DN_FIB_TABLE_HASHSZ 256 80static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ]; 81static DEFINE_RWLOCK(dn_fib_tables_lock); 82 83static struct kmem_cache *dn_hash_kmem __read_mostly; 84static int dn_fib_hash_zombies; 85 86static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz) 87{ 88 u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order); 89 h ^= (h >> 10); 90 h ^= (h >> 6); 91 h &= DZ_HASHMASK(dz); 92 return *(dn_fib_idx_t *)&h; 93} 94 95static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz) 96{ 97 dn_fib_key_t k; 98 k.datum = dst & DZ_MASK(dz); 99 return k; 100} 101 102static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz) 103{ 104 return &dz->dz_hash[dn_hash(key, dz).datum]; 105} 106 107static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz) 108{ 109 return dz->dz_hash[dn_hash(key, dz).datum]; 110} 111 112static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b) 113{ 114 return a.datum == b.datum; 115} 116 117static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b) 118{ 119 return a.datum <= b.datum; 120} 121 122static inline void dn_rebuild_zone(struct dn_zone *dz, 123 struct dn_fib_node **old_ht, 124 int old_divisor) 125{ 126 struct dn_fib_node *f, **fp, *next; 127 int i; 128 129 for(i = 0; i < old_divisor; i++) { 130 for(f = old_ht[i]; f; f = next) { 131 next = f->fn_next; 132 for(fp = dn_chain_p(f->fn_key, dz); 133 *fp && dn_key_leq((*fp)->fn_key, f->fn_key); 134 fp = &(*fp)->fn_next) 135 /* NOTHING */; 136 f->fn_next = *fp; 137 *fp = f; 138 } 139 } 140} 141 142static void dn_rehash_zone(struct dn_zone *dz) 143{ 144 struct dn_fib_node **ht, **old_ht; 145 int old_divisor, new_divisor; 146 u32 new_hashmask; 147 148 old_divisor = dz->dz_divisor; 149 150 switch (old_divisor) { 151 case 16: 152 new_divisor = 256; 153 new_hashmask = 0xFF; 154 break; 155 default: 156 printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n", 157 old_divisor); 158 case 256: 159 new_divisor = 1024; 160 new_hashmask = 0x3FF; 161 break; 162 } 163 164 ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL); 165 if (ht == NULL) 166 return; 167 168 write_lock_bh(&dn_fib_tables_lock); 169 old_ht = dz->dz_hash; 170 dz->dz_hash = ht; 171 dz->dz_hashmask = new_hashmask; 172 dz->dz_divisor = new_divisor; 173 dn_rebuild_zone(dz, old_ht, old_divisor); 174 write_unlock_bh(&dn_fib_tables_lock); 175 kfree(old_ht); 176} 177 178static void dn_free_node(struct dn_fib_node *f) 179{ 180 dn_fib_release_info(DN_FIB_INFO(f)); 181 kmem_cache_free(dn_hash_kmem, f); 182} 183 184 185static struct dn_zone *dn_new_zone(struct dn_hash *table, int z) 186{ 187 int i; 188 struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL); 189 if (!dz) 190 return NULL; 191 192 if (z) { 193 dz->dz_divisor = 16; 194 dz->dz_hashmask = 0x0F; 195 } else { 196 dz->dz_divisor = 1; 197 dz->dz_hashmask = 0; 198 } 199 200 dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL); 201 if (!dz->dz_hash) { 202 kfree(dz); 203 return NULL; 204 } 205 206 dz->dz_order = z; 207 dz->dz_mask = dnet_make_mask(z); 208 209 for(i = z + 1; i <= 16; i++) 210 if (table->dh_zones[i]) 211 break; 212 213 write_lock_bh(&dn_fib_tables_lock); 214 if (i>16) { 215 dz->dz_next = table->dh_zone_list; 216 table->dh_zone_list = dz; 217 } else { 218 dz->dz_next = table->dh_zones[i]->dz_next; 219 table->dh_zones[i]->dz_next = dz; 220 } 221 table->dh_zones[z] = dz; 222 write_unlock_bh(&dn_fib_tables_lock); 223 return dz; 224} 225 226 227static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi) 228{ 229 struct rtnexthop *nhp; 230 int nhlen; 231 232 if (attrs[RTA_PRIORITY] && 233 nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority) 234 return 1; 235 236 if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) { 237 if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) && 238 (!attrs[RTA_GATEWAY] || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw)) 239 return 0; 240 return 1; 241 } 242 243 if (!attrs[RTA_MULTIPATH]) 244 return 0; 245 246 nhp = nla_data(attrs[RTA_MULTIPATH]); 247 nhlen = nla_len(attrs[RTA_MULTIPATH]); 248 249 for_nexthops(fi) { 250 int attrlen = nhlen - sizeof(struct rtnexthop); 251 __le16 gw; 252 253 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0) 254 return -EINVAL; 255 if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif) 256 return 1; 257 if (attrlen) { 258 struct nlattr *gw_attr; 259 260 gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY); 261 gw = gw_attr ? nla_get_le16(gw_attr) : 0; 262 263 if (gw && gw != nh->nh_gw) 264 return 1; 265 } 266 nhp = RTNH_NEXT(nhp); 267 } endfor_nexthops(fi); 268 269 return 0; 270} 271 272static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi) 273{ 274 size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg)) 275 + nla_total_size(4) /* RTA_TABLE */ 276 + nla_total_size(2) /* RTA_DST */ 277 + nla_total_size(4) /* RTA_PRIORITY */ 278 + nla_total_size(TCP_CA_NAME_MAX); /* RTAX_CC_ALGO */ 279 280 /* space for nested metrics */ 281 payload += nla_total_size((RTAX_MAX * nla_total_size(4))); 282 283 if (fi->fib_nhs) { 284 /* Also handles the special case fib_nhs == 1 */ 285 286 /* each nexthop is packed in an attribute */ 287 size_t nhsize = nla_total_size(sizeof(struct rtnexthop)); 288 289 /* may contain a gateway attribute */ 290 nhsize += nla_total_size(4); 291 292 /* all nexthops are packed in a nested attribute */ 293 payload += nla_total_size(fi->fib_nhs * nhsize); 294 } 295 296 return payload; 297} 298 299static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event, 300 u32 tb_id, u8 type, u8 scope, void *dst, int dst_len, 301 struct dn_fib_info *fi, unsigned int flags) 302{ 303 struct rtmsg *rtm; 304 struct nlmsghdr *nlh; 305 306 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); 307 if (!nlh) 308 return -EMSGSIZE; 309 310 rtm = nlmsg_data(nlh); 311 rtm->rtm_family = AF_DECnet; 312 rtm->rtm_dst_len = dst_len; 313 rtm->rtm_src_len = 0; 314 rtm->rtm_tos = 0; 315 rtm->rtm_table = tb_id; 316 rtm->rtm_flags = fi->fib_flags; 317 rtm->rtm_scope = scope; 318 rtm->rtm_type = type; 319 rtm->rtm_protocol = fi->fib_protocol; 320 321 if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0) 322 goto errout; 323 324 if (rtm->rtm_dst_len && 325 nla_put(skb, RTA_DST, 2, dst) < 0) 326 goto errout; 327 328 if (fi->fib_priority && 329 nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0) 330 goto errout; 331 332 if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0) 333 goto errout; 334 335 if (fi->fib_nhs == 1) { 336 if (fi->fib_nh->nh_gw && 337 nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0) 338 goto errout; 339 340 if (fi->fib_nh->nh_oif && 341 nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif) < 0) 342 goto errout; 343 } 344 345 if (fi->fib_nhs > 1) { 346 struct rtnexthop *nhp; 347 struct nlattr *mp_head; 348 349 if (!(mp_head = nla_nest_start(skb, RTA_MULTIPATH))) 350 goto errout; 351 352 for_nexthops(fi) { 353 if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp)))) 354 goto errout; 355 356 nhp->rtnh_flags = nh->nh_flags & 0xFF; 357 nhp->rtnh_hops = nh->nh_weight - 1; 358 nhp->rtnh_ifindex = nh->nh_oif; 359 360 if (nh->nh_gw && 361 nla_put_le16(skb, RTA_GATEWAY, nh->nh_gw) < 0) 362 goto errout; 363 364 nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp; 365 } endfor_nexthops(fi); 366 367 nla_nest_end(skb, mp_head); 368 } 369 370 nlmsg_end(skb, nlh); 371 return 0; 372 373errout: 374 nlmsg_cancel(skb, nlh); 375 return -EMSGSIZE; 376} 377 378 379static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id, 380 struct nlmsghdr *nlh, struct netlink_skb_parms *req) 381{ 382 struct sk_buff *skb; 383 u32 portid = req ? req->portid : 0; 384 int err = -ENOBUFS; 385 386 skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f)), GFP_KERNEL); 387 if (skb == NULL) 388 goto errout; 389 390 err = dn_fib_dump_info(skb, portid, nlh->nlmsg_seq, event, tb_id, 391 f->fn_type, f->fn_scope, &f->fn_key, z, 392 DN_FIB_INFO(f), 0); 393 if (err < 0) { 394 /* -EMSGSIZE implies BUG in dn_fib_nlmsg_size() */ 395 WARN_ON(err == -EMSGSIZE); 396 kfree_skb(skb); 397 goto errout; 398 } 399 rtnl_notify(skb, &init_net, portid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL); 400 return; 401errout: 402 if (err < 0) 403 rtnl_set_sk_err(&init_net, RTNLGRP_DECnet_ROUTE, err); 404} 405 406static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb, 407 struct netlink_callback *cb, 408 struct dn_fib_table *tb, 409 struct dn_zone *dz, 410 struct dn_fib_node *f) 411{ 412 int i, s_i; 413 414 s_i = cb->args[4]; 415 for(i = 0; f; i++, f = f->fn_next) { 416 if (i < s_i) 417 continue; 418 if (f->fn_state & DN_S_ZOMBIE) 419 continue; 420 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).portid, 421 cb->nlh->nlmsg_seq, 422 RTM_NEWROUTE, 423 tb->n, 424 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type, 425 f->fn_scope, &f->fn_key, dz->dz_order, 426 f->fn_info, NLM_F_MULTI) < 0) { 427 cb->args[4] = i; 428 return -1; 429 } 430 } 431 cb->args[4] = i; 432 return skb->len; 433} 434 435static __inline__ int dn_hash_dump_zone(struct sk_buff *skb, 436 struct netlink_callback *cb, 437 struct dn_fib_table *tb, 438 struct dn_zone *dz) 439{ 440 int h, s_h; 441 442 s_h = cb->args[3]; 443 for(h = 0; h < dz->dz_divisor; h++) { 444 if (h < s_h) 445 continue; 446 if (h > s_h) 447 memset(&cb->args[4], 0, sizeof(cb->args) - 4*sizeof(cb->args[0])); 448 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL) 449 continue; 450 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) { 451 cb->args[3] = h; 452 return -1; 453 } 454 } 455 cb->args[3] = h; 456 return skb->len; 457} 458 459static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb, 460 struct netlink_callback *cb) 461{ 462 int m, s_m; 463 struct dn_zone *dz; 464 struct dn_hash *table = (struct dn_hash *)tb->data; 465 466 s_m = cb->args[2]; 467 read_lock(&dn_fib_tables_lock); 468 for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) { 469 if (m < s_m) 470 continue; 471 if (m > s_m) 472 memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0])); 473 474 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) { 475 cb->args[2] = m; 476 read_unlock(&dn_fib_tables_lock); 477 return -1; 478 } 479 } 480 read_unlock(&dn_fib_tables_lock); 481 cb->args[2] = m; 482 483 return skb->len; 484} 485 486int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb) 487{ 488 struct net *net = sock_net(skb->sk); 489 unsigned int h, s_h; 490 unsigned int e = 0, s_e; 491 struct dn_fib_table *tb; 492 int dumped = 0; 493 494 if (!net_eq(net, &init_net)) 495 return 0; 496 497 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) && 498 ((struct rtmsg *)nlmsg_data(cb->nlh))->rtm_flags&RTM_F_CLONED) 499 return dn_cache_dump(skb, cb); 500 501 s_h = cb->args[0]; 502 s_e = cb->args[1]; 503 504 for (h = s_h; h < DN_FIB_TABLE_HASHSZ; h++, s_h = 0) { 505 e = 0; 506 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist) { 507 if (e < s_e) 508 goto next; 509 if (dumped) 510 memset(&cb->args[2], 0, sizeof(cb->args) - 511 2 * sizeof(cb->args[0])); 512 if (tb->dump(tb, skb, cb) < 0) 513 goto out; 514 dumped = 1; 515next: 516 e++; 517 } 518 } 519out: 520 cb->args[1] = e; 521 cb->args[0] = h; 522 523 return skb->len; 524} 525 526static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[], 527 struct nlmsghdr *n, struct netlink_skb_parms *req) 528{ 529 struct dn_hash *table = (struct dn_hash *)tb->data; 530 struct dn_fib_node *new_f, *f, **fp, **del_fp; 531 struct dn_zone *dz; 532 struct dn_fib_info *fi; 533 int z = r->rtm_dst_len; 534 int type = r->rtm_type; 535 dn_fib_key_t key; 536 int err; 537 538 if (z > 16) 539 return -EINVAL; 540 541 dz = table->dh_zones[z]; 542 if (!dz && !(dz = dn_new_zone(table, z))) 543 return -ENOBUFS; 544 545 dz_key_0(key); 546 if (attrs[RTA_DST]) { 547 __le16 dst = nla_get_le16(attrs[RTA_DST]); 548 if (dst & ~DZ_MASK(dz)) 549 return -EINVAL; 550 key = dz_key(dst, dz); 551 } 552 553 if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL) 554 return err; 555 556 if (dz->dz_nent > (dz->dz_divisor << 2) && 557 dz->dz_divisor > DN_MAX_DIVISOR && 558 (z==16 || (1<<z) > dz->dz_divisor)) 559 dn_rehash_zone(dz); 560 561 fp = dn_chain_p(key, dz); 562 563 DN_FIB_SCAN(f, fp) { 564 if (dn_key_leq(key, f->fn_key)) 565 break; 566 } 567 568 del_fp = NULL; 569 570 if (f && (f->fn_state & DN_S_ZOMBIE) && 571 dn_key_eq(f->fn_key, key)) { 572 del_fp = fp; 573 fp = &f->fn_next; 574 f = *fp; 575 goto create; 576 } 577 578 DN_FIB_SCAN_KEY(f, fp, key) { 579 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority) 580 break; 581 } 582 583 if (f && dn_key_eq(f->fn_key, key) && 584 fi->fib_priority == DN_FIB_INFO(f)->fib_priority) { 585 struct dn_fib_node **ins_fp; 586 587 err = -EEXIST; 588 if (n->nlmsg_flags & NLM_F_EXCL) 589 goto out; 590 591 if (n->nlmsg_flags & NLM_F_REPLACE) { 592 del_fp = fp; 593 fp = &f->fn_next; 594 f = *fp; 595 goto replace; 596 } 597 598 ins_fp = fp; 599 err = -EEXIST; 600 601 DN_FIB_SCAN_KEY(f, fp, key) { 602 if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority) 603 break; 604 if (f->fn_type == type && 605 f->fn_scope == r->rtm_scope && 606 DN_FIB_INFO(f) == fi) 607 goto out; 608 } 609 610 if (!(n->nlmsg_flags & NLM_F_APPEND)) { 611 fp = ins_fp; 612 f = *fp; 613 } 614 } 615 616create: 617 err = -ENOENT; 618 if (!(n->nlmsg_flags & NLM_F_CREATE)) 619 goto out; 620 621replace: 622 err = -ENOBUFS; 623 new_f = kmem_cache_zalloc(dn_hash_kmem, GFP_KERNEL); 624 if (new_f == NULL) 625 goto out; 626 627 new_f->fn_key = key; 628 new_f->fn_type = type; 629 new_f->fn_scope = r->rtm_scope; 630 DN_FIB_INFO(new_f) = fi; 631 632 new_f->fn_next = f; 633 write_lock_bh(&dn_fib_tables_lock); 634 *fp = new_f; 635 write_unlock_bh(&dn_fib_tables_lock); 636 dz->dz_nent++; 637 638 if (del_fp) { 639 f = *del_fp; 640 write_lock_bh(&dn_fib_tables_lock); 641 *del_fp = f->fn_next; 642 write_unlock_bh(&dn_fib_tables_lock); 643 644 if (!(f->fn_state & DN_S_ZOMBIE)) 645 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req); 646 if (f->fn_state & DN_S_ACCESSED) 647 dn_rt_cache_flush(-1); 648 dn_free_node(f); 649 dz->dz_nent--; 650 } else { 651 dn_rt_cache_flush(-1); 652 } 653 654 dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req); 655 656 return 0; 657out: 658 dn_fib_release_info(fi); 659 return err; 660} 661 662 663static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[], 664 struct nlmsghdr *n, struct netlink_skb_parms *req) 665{ 666 struct dn_hash *table = (struct dn_hash*)tb->data; 667 struct dn_fib_node **fp, **del_fp, *f; 668 int z = r->rtm_dst_len; 669 struct dn_zone *dz; 670 dn_fib_key_t key; 671 int matched; 672 673 674 if (z > 16) 675 return -EINVAL; 676 677 if ((dz = table->dh_zones[z]) == NULL) 678 return -ESRCH; 679 680 dz_key_0(key); 681 if (attrs[RTA_DST]) { 682 __le16 dst = nla_get_le16(attrs[RTA_DST]); 683 if (dst & ~DZ_MASK(dz)) 684 return -EINVAL; 685 key = dz_key(dst, dz); 686 } 687 688 fp = dn_chain_p(key, dz); 689 690 DN_FIB_SCAN(f, fp) { 691 if (dn_key_eq(f->fn_key, key)) 692 break; 693 if (dn_key_leq(key, f->fn_key)) 694 return -ESRCH; 695 } 696 697 matched = 0; 698 del_fp = NULL; 699 DN_FIB_SCAN_KEY(f, fp, key) { 700 struct dn_fib_info *fi = DN_FIB_INFO(f); 701 702 if (f->fn_state & DN_S_ZOMBIE) 703 return -ESRCH; 704 705 matched++; 706 707 if (del_fp == NULL && 708 (!r->rtm_type || f->fn_type == r->rtm_type) && 709 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) && 710 (!r->rtm_protocol || 711 fi->fib_protocol == r->rtm_protocol) && 712 dn_fib_nh_match(r, n, attrs, fi) == 0) 713 del_fp = fp; 714 } 715 716 if (del_fp) { 717 f = *del_fp; 718 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req); 719 720 if (matched != 1) { 721 write_lock_bh(&dn_fib_tables_lock); 722 *del_fp = f->fn_next; 723 write_unlock_bh(&dn_fib_tables_lock); 724 725 if (f->fn_state & DN_S_ACCESSED) 726 dn_rt_cache_flush(-1); 727 dn_free_node(f); 728 dz->dz_nent--; 729 } else { 730 f->fn_state |= DN_S_ZOMBIE; 731 if (f->fn_state & DN_S_ACCESSED) { 732 f->fn_state &= ~DN_S_ACCESSED; 733 dn_rt_cache_flush(-1); 734 } 735 if (++dn_fib_hash_zombies > 128) 736 dn_fib_flush(); 737 } 738 739 return 0; 740 } 741 742 return -ESRCH; 743} 744 745static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table) 746{ 747 int found = 0; 748 struct dn_fib_node *f; 749 750 while((f = *fp) != NULL) { 751 struct dn_fib_info *fi = DN_FIB_INFO(f); 752 753 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) { 754 write_lock_bh(&dn_fib_tables_lock); 755 *fp = f->fn_next; 756 write_unlock_bh(&dn_fib_tables_lock); 757 758 dn_free_node(f); 759 found++; 760 continue; 761 } 762 fp = &f->fn_next; 763 } 764 765 return found; 766} 767 768static int dn_fib_table_flush(struct dn_fib_table *tb) 769{ 770 struct dn_hash *table = (struct dn_hash *)tb->data; 771 struct dn_zone *dz; 772 int found = 0; 773 774 dn_fib_hash_zombies = 0; 775 for(dz = table->dh_zone_list; dz; dz = dz->dz_next) { 776 int i; 777 int tmp = 0; 778 for(i = dz->dz_divisor-1; i >= 0; i--) 779 tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table); 780 dz->dz_nent -= tmp; 781 found += tmp; 782 } 783 784 return found; 785} 786 787static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowidn *flp, struct dn_fib_res *res) 788{ 789 int err; 790 struct dn_zone *dz; 791 struct dn_hash *t = (struct dn_hash *)tb->data; 792 793 read_lock(&dn_fib_tables_lock); 794 for(dz = t->dh_zone_list; dz; dz = dz->dz_next) { 795 struct dn_fib_node *f; 796 dn_fib_key_t k = dz_key(flp->daddr, dz); 797 798 for(f = dz_chain(k, dz); f; f = f->fn_next) { 799 if (!dn_key_eq(k, f->fn_key)) { 800 if (dn_key_leq(k, f->fn_key)) 801 break; 802 else 803 continue; 804 } 805 806 f->fn_state |= DN_S_ACCESSED; 807 808 if (f->fn_state&DN_S_ZOMBIE) 809 continue; 810 811 if (f->fn_scope < flp->flowidn_scope) 812 continue; 813 814 err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res); 815 816 if (err == 0) { 817 res->type = f->fn_type; 818 res->scope = f->fn_scope; 819 res->prefixlen = dz->dz_order; 820 goto out; 821 } 822 if (err < 0) 823 goto out; 824 } 825 } 826 err = 1; 827out: 828 read_unlock(&dn_fib_tables_lock); 829 return err; 830} 831 832 833struct dn_fib_table *dn_fib_get_table(u32 n, int create) 834{ 835 struct dn_fib_table *t; 836 unsigned int h; 837 838 if (n < RT_TABLE_MIN) 839 return NULL; 840 841 if (n > RT_TABLE_MAX) 842 return NULL; 843 844 h = n & (DN_FIB_TABLE_HASHSZ - 1); 845 rcu_read_lock(); 846 hlist_for_each_entry_rcu(t, &dn_fib_table_hash[h], hlist) { 847 if (t->n == n) { 848 rcu_read_unlock(); 849 return t; 850 } 851 } 852 rcu_read_unlock(); 853 854 if (!create) 855 return NULL; 856 857 if (in_interrupt()) { 858 net_dbg_ratelimited("DECnet: BUG! Attempt to create routing table from interrupt\n"); 859 return NULL; 860 } 861 862 t = kzalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash), 863 GFP_KERNEL); 864 if (t == NULL) 865 return NULL; 866 867 t->n = n; 868 t->insert = dn_fib_table_insert; 869 t->delete = dn_fib_table_delete; 870 t->lookup = dn_fib_table_lookup; 871 t->flush = dn_fib_table_flush; 872 t->dump = dn_fib_table_dump; 873 hlist_add_head_rcu(&t->hlist, &dn_fib_table_hash[h]); 874 875 return t; 876} 877 878struct dn_fib_table *dn_fib_empty_table(void) 879{ 880 u32 id; 881 882 for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++) 883 if (dn_fib_get_table(id, 0) == NULL) 884 return dn_fib_get_table(id, 1); 885 return NULL; 886} 887 888void dn_fib_flush(void) 889{ 890 int flushed = 0; 891 struct dn_fib_table *tb; 892 unsigned int h; 893 894 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) { 895 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist) 896 flushed += tb->flush(tb); 897 } 898 899 if (flushed) 900 dn_rt_cache_flush(-1); 901} 902 903void __init dn_fib_table_init(void) 904{ 905 dn_hash_kmem = kmem_cache_create("dn_fib_info_cache", 906 sizeof(struct dn_fib_info), 907 0, SLAB_HWCACHE_ALIGN, 908 NULL); 909} 910 911void __exit dn_fib_table_cleanup(void) 912{ 913 struct dn_fib_table *t; 914 struct hlist_node *next; 915 unsigned int h; 916 917 write_lock(&dn_fib_tables_lock); 918 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) { 919 hlist_for_each_entry_safe(t, next, &dn_fib_table_hash[h], 920 hlist) { 921 hlist_del(&t->hlist); 922 kfree(t); 923 } 924 } 925 write_unlock(&dn_fib_tables_lock); 926} 927