net/decnet/dn_table.c

   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/config.h>
  16 #include <linux/string.h>
  17 #include <linux/net.h>
  18 #include <linux/socket.h>
  19 #include <linux/sockios.h>
  20 #include <linux/init.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/netlink.h>
  23 #include <linux/rtnetlink.h>
  24 #include <linux/proc_fs.h>
  25 #include <linux/netdevice.h>
  26 #include <linux/timer.h>
  27 #include <linux/spinlock.h>
  28 #include <asm/atomic.h>
  29 #include <asm/uaccess.h>
  30 #include <linux/route.h> /* RTF_xxx */
  31 #include <net/neighbour.h>
  32 #include <net/dst.h>
  33 #include <net/dn.h>
  34 #include <net/dn_route.h>
  35 #include <net/dn_fib.h>
  36 #include <net/dn_neigh.h>
  37 #include <net/dn_dev.h>
  38
  39 struct dn_zone
  40 {
  41         struct dn_zone          *dz_next;
  42         struct dn_fib_node      **dz_hash;
  43         int                     dz_nent;
  44         int                     dz_divisor;
  45         u32                     dz_hashmask;
  46 #define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
  47         int                     dz_order;
  48         u32                     dz_mask;
  49 #define DZ_MASK(dz)     ((dz)->dz_mask)
  50 };
  51
  52 struct dn_hash
  53 {
  54         struct dn_zone  *dh_zones[17];
  55         struct dn_zone  *dh_zone_list;
  56 };
  57
  58 #define dz_key_0(key)           ((key).datum = 0)
  59 #define dz_prefix(key,dz)       ((key).datum)
  60
  61 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
  62         for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
  63
  64 #define endfor_nexthops(fi) }
  65
  66 #define DN_MAX_DIVISOR 1024
  67 #define DN_S_ZOMBIE 1
  68 #define DN_S_ACCESSED 2
  69
  70 #define DN_FIB_SCAN(f, fp) \
  71 for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
  72
  73 #define DN_FIB_SCAN_KEY(f, fp, key) \
  74 for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
  75
  76
  77 static rwlock_t dn_fib_tables_lock = RW_LOCK_UNLOCKED;
  78 static struct dn_fib_table *dn_fib_tables[DN_NUM_TABLES + 1];
  79
  80 static kmem_cache_t *dn_hash_kmem;
  81 static int dn_fib_hash_zombies;
  82
  83 static __inline__ dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
  84 {
  85         u32 h = ntohs(key.datum)>>(16 - dz->dz_order);
  86         h ^= (h >> 10);
  87         h ^= (h >> 6);
  88         h ^= (h >> 3);
  89         h &= DZ_HASHMASK(dz);
  90         return *(dn_fib_idx_t *)&h;
  91 }
  92
  93 static __inline__ dn_fib_key_t dz_key(u16 dst, struct dn_zone *dz)
  94 {
  95         dn_fib_key_t k;
  96         k.datum = dst & DZ_MASK(dz);
  97         return k;
  98 }
  99
 100 static __inline__ struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
 101 {
 102         return &dz->dz_hash[dn_hash(key, dz).datum];
 103 }
 104
 105 static __inline__ struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
 106 {
 107         return dz->dz_hash[dn_hash(key, dz).datum];
 108 }
 109
 110 static __inline__ int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
 111 {
 112         return a.datum == b.datum;
 113 }
 114
 115 static __inline__ int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
 116 {
 117         return a.datum <= b.datum;
 118 }
 119
 120 static __inline__ void dn_rebuild_zone(struct dn_zone *dz,
 121                                         struct dn_fib_node **old_ht,
 122                                         int old_divisor)
 123 {
 124         int i;
 125         struct dn_fib_node *f, **fp, *next;
 126
 127         for(i = 0; i < old_divisor; i++) {
 128                 for(f = old_ht[i]; f; f = f->fn_next) {
 129                         next = f->fn_next;
 130                         for(fp = dn_chain_p(f->fn_key, dz);
 131                                 *fp && dn_key_leq((*fp)->fn_key, f->fn_key);
 132                                 fp = &(*fp)->fn_next)
 133                                 /* NOTHING */;
 134                         f->fn_next = *fp;
 135                         *fp = f;
 136                 }
 137         }
 138 }
 139
 140 static void dn_rehash_zone(struct dn_zone *dz)
 141 {
 142         struct dn_fib_node **ht, **old_ht;
 143         int old_divisor, new_divisor;
 144         u32 new_hashmask;
 145
 146         old_divisor = dz->dz_divisor;
 147
 148         switch(old_divisor) {
 149                 case 16:
 150                         new_divisor = 256;
 151                         new_hashmask = 0xFF;
 152                         break;
 153                 default:
 154                         printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n", old_divisor);
 155                 case 256:
 156                         new_divisor = 1024;
 157                         new_hashmask = 0x3FF;
 158                         break;
 159         }
 160
 161         ht = kmalloc(new_divisor*sizeof(struct dn_fib_node*), GFP_KERNEL);
 162
 163         if (ht == NULL)
 164                 return;
 165
 166         memset(ht, 0, new_divisor*sizeof(struct dn_fib_node *));
 167         write_lock_bh(&dn_fib_tables_lock);
 168         old_ht = dz->dz_hash;
 169         dz->dz_hash = ht;
 170         dz->dz_hashmask = new_hashmask;
 171         dz->dz_divisor = new_divisor;
 172         dn_rebuild_zone(dz, old_ht, old_divisor);
 173         write_unlock_bh(&dn_fib_tables_lock);
 174         kfree(old_ht);
 175 }
 176
 177 static void dn_free_node(struct dn_fib_node *f)
 178 {
 179         dn_fib_release_info(DN_FIB_INFO(f));
 180         kmem_cache_free(dn_hash_kmem, f);
 181 }
 182
 183
 184 static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
 185 {
 186         int i;
 187         struct dn_zone *dz = kmalloc(sizeof(struct dn_zone), GFP_KERNEL);
 188         if (!dz)
 189                 return NULL;
 190
 191         memset(dz, 0, sizeof(struct dn_zone));
 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 = kmalloc(dz->dz_divisor*sizeof(struct dn_fib_node *), GFP_KERNEL);
 201
 202         if (!dz->dz_hash) {
 203                 kfree(dz);
 204                 return NULL;
 205         }
 206
 207         memset(dz->dz_hash, 0, dz->dz_divisor*sizeof(struct dn_fib_node*));
 208         dz->dz_order = z;
 209         dz->dz_mask = dnet_make_mask(z);
 210
 211         for(i = z + 1; i <= 16; i++)
 212                 if (table->dh_zones[i])
 213                         break;
 214
 215         write_lock_bh(&dn_fib_tables_lock);
 216         if (i>16) {
 217                 dz->dz_next = table->dh_zone_list;
 218                 table->dh_zone_list = dz;
 219         } else {
 220                 dz->dz_next = table->dh_zones[i]->dz_next;
 221                 table->dh_zones[i]->dz_next = dz;
 222         }
 223         table->dh_zones[z] = dz;
 224         write_unlock_bh(&dn_fib_tables_lock);
 225         return dz;
 226 }
 227
 228
 229 static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern_rta *rta, struct dn_fib_info *fi)
 230 {
 231         struct rtnexthop *nhp;
 232         int nhlen;
 233
 234         if (rta->rta_priority && *rta->rta_priority != fi->fib_priority)
 235                 return 1;
 236
 237         if (rta->rta_oif || rta->rta_gw) {
 238                 if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
 239                     (!rta->rta_gw  || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 2) == 0))
 240                         return 0;
 241                 return 1;
 242         }
 243
 244         if (rta->rta_mp == NULL)
 245                 return 0;
 246
 247         nhp = RTA_DATA(rta->rta_mp);
 248         nhlen = RTA_PAYLOAD(rta->rta_mp);
 249
 250         for_nexthops(fi) {
 251                 int attrlen = nhlen - sizeof(struct rtnexthop);
 252                 dn_address gw;
 253
 254                 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
 255                         return -EINVAL;
 256                 if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
 257                         return 1;
 258                 if (attrlen) {
 259                         gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
 260
 261                         if (gw && gw != nh->nh_gw)
 262                                 return 1;
 263                 }
 264                 nhp = RTNH_NEXT(nhp);
 265         } endfor_nexthops(fi);
 266
 267         return 0;
 268 }
 269
 270 static int dn_fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
 271                         u8 tb_id, u8 type, u8 scope, void *dst, int dst_len,
 272                         struct dn_fib_info *fi)
 273 {
 274         struct rtmsg *rtm;
 275         struct nlmsghdr *nlh;
 276         unsigned char *b = skb->tail;
 277
 278         nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*rtm));
 279         rtm = NLMSG_DATA(nlh);
 280         rtm->rtm_family = AF_DECnet;
 281         rtm->rtm_dst_len = dst_len;
 282         rtm->rtm_src_len = 0;
 283         rtm->rtm_tos = 0;
 284         rtm->rtm_table = tb_id;
 285         rtm->rtm_flags = fi->fib_flags;
 286         rtm->rtm_scope = scope;
 287         rtm->rtm_type  = type;
 288         if (rtm->rtm_dst_len)
 289                 RTA_PUT(skb, RTA_DST, 2, dst);
 290         rtm->rtm_protocol = fi->fib_protocol;
 291         if (fi->fib_priority)
 292                 RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
 293         if (fi->fib_nhs == 1) {
 294                 if (fi->fib_nh->nh_gw)
 295                         RTA_PUT(skb, RTA_GATEWAY, 2, &fi->fib_nh->nh_gw);
 296                 if (fi->fib_nh->nh_oif)
 297                         RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
 298         }
 299         if (fi->fib_nhs > 1) {
 300                 struct rtnexthop *nhp;
 301                 struct rtattr *mp_head;
 302                 if (skb_tailroom(skb) <= RTA_SPACE(0))
 303                         goto rtattr_failure;
 304                 mp_head = (struct rtattr *)skb_put(skb, RTA_SPACE(0));
 305
 306                 for_nexthops(fi) {
 307                         if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
 308                                 goto rtattr_failure;
 309                         nhp = (struct rtnexthop *)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
 310                         nhp->rtnh_flags = nh->nh_flags & 0xFF;
 311                         nhp->rtnh_hops = nh->nh_weight - 1;
 312                         nhp->rtnh_ifindex = nh->nh_oif;
 313                         if (nh->nh_gw)
 314                                 RTA_PUT(skb, RTA_GATEWAY, 2, &nh->nh_gw);
 315                         nhp->rtnh_len = skb->tail - (unsigned char *)nhp;
 316                 } endfor_nexthops(fi);
 317                 mp_head->rta_type = RTA_MULTIPATH;
 318                 mp_head->rta_len = skb->tail - (u8*)mp_head;
 319         }
 320
 321         nlh->nlmsg_len = skb->tail - b;
 322         return skb->len;
 323
 324
 325 nlmsg_failure:
 326 rtattr_failure:
 327         skb_trim(skb, b - skb->data);
 328         return -1;
 329 }
 330
 331
 332 static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, int tb_id,
 333                         struct nlmsghdr *nlh, struct netlink_skb_parms *req)
 334 {
 335         struct sk_buff *skb;
 336         u32 pid = req ? req->pid : 0;
 337         int size = NLMSG_SPACE(sizeof(struct rtmsg) + 256);
 338
 339         skb = alloc_skb(size, GFP_KERNEL);
 340         if (!skb)
 341                 return;
 342
 343         if (dn_fib_dump_info(skb, pid, nlh->nlmsg_seq, event, tb_id,
 344                                 f->fn_type, f->fn_scope, &f->fn_key, z,
 345                                 DN_FIB_INFO(f)) < 0) {
 346                 kfree_skb(skb);
 347                 return;
 348         }
 349         NETLINK_CB(skb).dst_groups = RTMGRP_DECnet_ROUTE;
 350         if (nlh->nlmsg_flags & NLM_F_ECHO)
 351                 atomic_inc(&skb->users);
 352         netlink_broadcast(rtnl, skb, pid, RTMGRP_DECnet_ROUTE, GFP_KERNEL);
 353         if (nlh->nlmsg_flags & NLM_F_ECHO)
 354                 netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 355 }
 356
 357 static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
 358                                 struct netlink_callback *cb,
 359                                 struct dn_fib_table *tb,
 360                                 struct dn_zone *dz,
 361                                 struct dn_fib_node *f)
 362 {
 363         int i, s_i;
 364
 365         s_i = cb->args[3];
 366         for(i = 0; f; i++, f = f->fn_next) {
 367                 if (i < s_i)
 368                         continue;
 369                 if (f->fn_state & DN_S_ZOMBIE)
 370                         continue;
 371                 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
 372                                 cb->nlh->nlmsg_seq,
 373                                 RTM_NEWROUTE,
 374                                 tb->n,
 375                                 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
 376                                 f->fn_scope, &f->fn_key, dz->dz_order,
 377                                 f->fn_info) < 0) {
 378                         cb->args[3] = i;
 379                         return -1;
 380                 }
 381         }
 382         cb->args[3] = i;
 383         return skb->len;
 384 }
 385
 386 static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
 387                                 struct netlink_callback *cb,
 388                                 struct dn_fib_table *tb,
 389                                 struct dn_zone *dz)
 390 {
 391         int h, s_h;
 392
 393         s_h = cb->args[2];
 394         for(h = 0; h < dz->dz_divisor; h++) {
 395                 if (h < s_h)
 396                         continue;
 397                 if (h > s_h)
 398                         memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
 399                 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
 400                         continue;
 401                 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
 402                         cb->args[2] = h;
 403                         return -1;
 404                 }
 405         }
 406         cb->args[2] = h;
 407         return skb->len;
 408 }
 409
 410 static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
 411                                 struct netlink_callback *cb)
 412 {
 413         int m, s_m;
 414         struct dn_zone *dz;
 415         struct dn_hash *table = (struct dn_hash *)tb->data;
 416
 417         s_m = cb->args[1];
 418         read_lock(&dn_fib_tables_lock);
 419         for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
 420                 if (m < s_m)
 421                         continue;
 422                 if (m > s_m)
 423                         memset(&cb->args[2], 0, sizeof(cb->args) - 2*sizeof(cb->args[0]));
 424
 425                 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
 426                         cb->args[1] = m;
 427                         read_unlock(&dn_fib_tables_lock);
 428                         return -1;
 429                 }
 430         }
 431         read_unlock(&dn_fib_tables_lock);
 432         cb->args[1] = m;
 433
 434         return skb->len;
 435 }
 436
 437 static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
 438 {
 439         struct dn_hash *table = (struct dn_hash *)tb->data;
 440         struct dn_fib_node *new_f, *f, **fp, **del_fp;
 441         struct dn_zone *dz;
 442         struct dn_fib_info *fi;
 443         int z = r->rtm_dst_len;
 444         int type = r->rtm_type;
 445         dn_fib_key_t key;
 446         int err;
 447
 448         if (z > 16)
 449                 return -EINVAL;
 450
 451         dz = table->dh_zones[z];
 452         if (!dz && !(dz = dn_new_zone(table, z)))
 453                 return -ENOBUFS;
 454
 455         dz_key_0(key);
 456         if (rta->rta_dst) {
 457                 dn_address dst;
 458                 memcpy(&dst, rta->rta_dst, 2);
 459                 if (dst & ~DZ_MASK(dz))
 460                         return -EINVAL;
 461                 key = dz_key(dst, dz);
 462         }
 463
 464         if ((fi = dn_fib_create_info(r, rta, n, &err)) == NULL)
 465                 return err;
 466
 467         if (dz->dz_nent > (dz->dz_divisor << 2) &&
 468                         dz->dz_divisor > DN_MAX_DIVISOR &&
 469                         (z==16 || (1<<z) > dz->dz_divisor))
 470                 dn_rehash_zone(dz);
 471
 472         fp = dn_chain_p(key, dz);
 473
 474         DN_FIB_SCAN(f, fp) {
 475                 if (dn_key_leq(key, f->fn_key))
 476                         break;
 477         }
 478
 479         del_fp = NULL;
 480
 481         if (f && (f->fn_state & DN_S_ZOMBIE) &&
 482                         dn_key_eq(f->fn_key, key)) {
 483                 del_fp = fp;
 484                 fp = &f->fn_next;
 485                 f = *fp;
 486                 goto create;
 487         }
 488
 489         DN_FIB_SCAN_KEY(f, fp, key) {
 490                 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
 491                         break;
 492         }
 493
 494         if (f && dn_key_eq(f->fn_key, key) &&
 495                         fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
 496                 struct dn_fib_node **ins_fp;
 497
 498                 err = -EEXIST;
 499                 if (n->nlmsg_flags & NLM_F_EXCL)
 500                         goto out;
 501
 502                 if (n->nlmsg_flags & NLM_F_REPLACE) {
 503                         del_fp = fp;
 504                         fp = &f->fn_next;
 505                         f = *fp;
 506                         goto replace;
 507                 }
 508
 509                 ins_fp = fp;
 510                 err = -EEXIST;
 511
 512                 DN_FIB_SCAN_KEY(f, fp, key) {
 513                         if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
 514                                 break;
 515                         if (f->fn_type == type && f->fn_scope == r->rtm_scope
 516                                         && DN_FIB_INFO(f) == fi)
 517                                 goto out;
 518                 }
 519
 520                 if (!(n->nlmsg_flags & NLM_F_APPEND)) {
 521                         fp = ins_fp;
 522                         f = *fp;
 523                 }
 524         }
 525
 526 create:
 527         err = -ENOENT;
 528         if (!(n->nlmsg_flags & NLM_F_CREATE))
 529                 goto out;
 530
 531 replace:
 532         err = -ENOBUFS;
 533         new_f = kmem_cache_alloc(dn_hash_kmem, SLAB_KERNEL);
 534         if (new_f == NULL)
 535                 goto out;
 536
 537         memset(new_f, 0, sizeof(struct dn_fib_node));
 538
 539         new_f->fn_key = key;
 540         new_f->fn_type = type;
 541         new_f->fn_scope = r->rtm_scope;
 542         DN_FIB_INFO(new_f) = fi;
 543
 544         new_f->fn_next = f;
 545         write_lock_bh(&dn_fib_tables_lock);
 546         *fp = new_f;
 547         write_unlock_bh(&dn_fib_tables_lock);
 548         dz->dz_nent++;
 549
 550         if (del_fp) {
 551                 f = *del_fp;
 552                 write_lock_bh(&dn_fib_tables_lock);
 553                 *del_fp = f->fn_next;
 554                 write_unlock_bh(&dn_fib_tables_lock);
 555
 556                 if (!(f->fn_state & DN_S_ZOMBIE))
 557                         dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
 558                 if (f->fn_state & DN_S_ACCESSED)
 559                         dn_rt_cache_flush(-1);
 560                 dn_free_node(f);
 561                 dz->dz_nent--;
 562         } else {
 563                 dn_rt_cache_flush(-1);
 564         }
 565
 566         dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
 567
 568         return 0;
 569 out:
 570         dn_fib_release_info(fi);
 571         return err;
 572 }
 573
 574
 575 static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
 576 {
 577         struct dn_hash *table = (struct dn_hash*)tb->data;
 578         struct dn_fib_node **fp, **del_fp, *f;
 579         int z = r->rtm_dst_len;
 580         struct dn_zone *dz;
 581         dn_fib_key_t key;
 582         int matched;
 583
 584
 585         if (z > 16)
 586                 return -EINVAL;
 587
 588         if ((dz = table->dh_zones[z]) == NULL)
 589                 return -ESRCH;
 590
 591         dz_key_0(key);
 592         if (rta->rta_dst) {
 593                 dn_address dst;
 594                 memcpy(&dst, rta->rta_dst, 2);
 595                 if (dst & ~DZ_MASK(dz))
 596                         return -EINVAL;
 597                 key = dz_key(dst, dz);
 598         }
 599
 600         fp = dn_chain_p(key, dz);
 601
 602         DN_FIB_SCAN(f, fp) {
 603                 if (dn_key_eq(f->fn_key, key))
 604                         break;
 605                 if (dn_key_leq(key, f->fn_key))
 606                         return -ESRCH;
 607         }
 608
 609         matched = 0;
 610         del_fp = NULL;
 611         DN_FIB_SCAN_KEY(f, fp, key) {
 612                 struct dn_fib_info *fi = DN_FIB_INFO(f);
 613
 614                 if (f->fn_state & DN_S_ZOMBIE)
 615                         return -ESRCH;
 616
 617                 matched++;
 618
 619                 if (del_fp == NULL &&
 620                                 (!r->rtm_type || f->fn_type == r->rtm_type) &&
 621                                 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
 622                                 (!r->rtm_protocol ||
 623                                         fi->fib_protocol == r->rtm_protocol) &&
 624                                 dn_fib_nh_match(r, n, rta, fi) == 0)
 625                         del_fp = fp;
 626         }
 627
 628         if (del_fp) {
 629                 f = *del_fp;
 630                 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
 631
 632                 if (matched != 1) {
 633                         write_lock_bh(&dn_fib_tables_lock);
 634                         *del_fp = f->fn_next;
 635                         write_unlock_bh(&dn_fib_tables_lock);
 636
 637                         if (f->fn_state & DN_S_ACCESSED)
 638                                 dn_rt_cache_flush(-1);
 639                         dn_free_node(f);
 640                         dz->dz_nent--;
 641                 } else {
 642                         f->fn_state |= DN_S_ZOMBIE;
 643                         if (f->fn_state & DN_S_ACCESSED) {
 644                                 f->fn_state &= ~DN_S_ACCESSED;
 645                                 dn_rt_cache_flush(-1);
 646                         }
 647                         if (++dn_fib_hash_zombies > 128)
 648                                 dn_fib_flush();
 649                 }
 650
 651                 return 0;
 652         }
 653
 654         return -ESRCH;
 655 }
 656
 657 static __inline__ int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
 658 {
 659         int found = 0;
 660         struct dn_fib_node *f;
 661
 662         while((f = *fp) != NULL) {
 663                 struct dn_fib_info *fi = DN_FIB_INFO(f);
 664
 665                 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
 666                         write_lock_bh(&dn_fib_tables_lock);
 667                         *fp = f->fn_next;
 668                         write_unlock_bh(&dn_fib_tables_lock);
 669
 670                         dn_free_node(f);
 671                         found++;
 672                         continue;
 673                 }
 674                 fp = &f->fn_next;
 675         }
 676
 677         return found;
 678 }
 679
 680 static int dn_fib_table_flush(struct dn_fib_table *tb)
 681 {
 682         struct dn_hash *table = (struct dn_hash *)tb->data;
 683         struct dn_zone *dz;
 684         int found = 0;
 685
 686         dn_fib_hash_zombies = 0;
 687         for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
 688                 int i;
 689                 int tmp = 0;
 690                 for(i = dz->dz_divisor-1; i >= 0; i--)
 691                         tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
 692                 dz->dz_nent -= tmp;
 693                 found += tmp;
 694         }
 695
 696         return found;
 697 }
 698
 699 static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct dn_fib_key *
 700 key, struct dn_fib_res *res)
 701 {
 702         int err;
 703         struct dn_zone *dz;
 704         struct dn_hash *t = (struct dn_hash *)tb->data;
 705
 706         read_lock(&dn_fib_tables_lock);
 707         for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
 708                 struct dn_fib_node *f;
 709                 dn_fib_key_t k = dz_key(key->dst, dz);
 710
 711                 for(f = dz_chain(k, dz); f; f = f->fn_next) {
 712                         if (!dn_key_leq(k, f->fn_key))
 713                                 break;
 714                         else
 715                                 continue;
 716
 717                         f->fn_state |= DN_S_ACCESSED;
 718
 719                         if (f->fn_state&DN_S_ZOMBIE)
 720                                 continue;
 721                         if (f->fn_scope < key->scope)
 722                                 continue;
 723
 724                         err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), key, res);
 725                         if (err == 0) {
 726                                 res->type = f->fn_type;
 727                                 res->scope = f->fn_scope;
 728                                 res->prefixlen = dz->dz_order;
 729                                 goto out;
 730                         }
 731                         if (err < 0)
 732                                 goto out;
 733                 }
 734         }
 735         err = 1;
 736 out:
 737         read_unlock(&dn_fib_tables_lock);
 738         return err;
 739 }
 740
 741 #ifdef CONFIG_PROC_FS
 742
 743 static unsigned dn_fib_flag_trans(int type, int dead, u16 mask, struct dn_fib_info *fi)
 744 {
 745         static unsigned type2flags[RTN_MAX+1] = {
 746                 0, 0, 0, 0, 0, 0, 0, RTF_REJECT, RTF_REJECT, 0, 0, 0
 747         };
 748         unsigned flags = type2flags[type];
 749
 750         if (fi && fi->fib_nh->nh_gw)
 751                 flags |= RTF_GATEWAY;
 752         if (mask == 0xFFFF)
 753                 flags |= RTF_HOST;
 754         if (dead)
 755                 flags |= RTF_UP;
 756         return flags;
 757 }
 758
 759 static void dn_fib_node_get_info(int type, int dead, struct dn_fib_info *fi, u16 prefix, u16 mask, char *buffer)
 760 {
 761         int len;
 762         unsigned flags = dn_fib_flag_trans(type, dead, mask, fi);
 763
 764         if (fi) {
 765                 len = sprintf(buffer, "%s\t%04x\t%04x\t%04x\t%d\t%u\t%d\t%04x\t%d\t%u\t%u",
 766                                 fi->fib_dev ? fi->fib_dev->name : "*", prefix,
 767                                 fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority,
 768                                 mask, 0, 0, 0);
 769         } else {
 770                 len = sprintf(buffer, "*\t%04x\t%04x\t%04x\t%d\t%u\t%d\t%04x\t%d\t%u\t%u",
 771                                         prefix, 0,
 772                                         flags, 0, 0, 0,
 773                                         mask, 0, 0, 0);
 774         }
 775         memset(buffer+len, ' ', 127-len);
 776         buffer[127] = '\n';
 777 }
 778
 779 static int dn_fib_table_get_info(struct dn_fib_table *tb, char *buffer, int first, int count)
 780 {
 781         struct dn_hash *table = (struct dn_hash *)tb->data;
 782         struct dn_zone *dz;
 783         int pos = 0;
 784         int n = 0;
 785
 786         read_lock(&dn_fib_tables_lock);
 787         for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
 788                 int i;
 789                 struct dn_fib_node *f;
 790                 int maxslot = dz->dz_divisor;
 791                 struct dn_fib_node **fp = dz->dz_hash;
 792
 793                 if (dz->dz_nent == 0)
 794                         continue;
 795
 796                 if (pos + dz->dz_nent < first) {
 797                         pos += dz->dz_nent;
 798                         continue;
 799                 }
 800
 801                 for(i = 0; i < maxslot; i++, fp++) {
 802                         for(f = *fp; f ; f = f->fn_next) {
 803                                 if (++pos <= first)
 804                                         continue;
 805                                 dn_fib_node_get_info(f->fn_type,
 806                                                 f->fn_state & DN_S_ZOMBIE,
 807                                                 DN_FIB_INFO(f),
 808                                                 dz_prefix(f->fn_key, dz),
 809                                                 DZ_MASK(dz), buffer);
 810                                 buffer += 128;
 811                                 if (++n >= count)
 812                                         goto out;
 813                         }
 814                 }
 815         }
 816 out:
 817         read_unlock(&dn_fib_tables_lock);
 818         return n;
 819 }
 820 #endif /* CONFIG_PROC_FS */
 821
 822 struct dn_fib_table *dn_fib_get_table(int n, int create)
 823 {
 824         struct dn_fib_table *t;
 825
 826         if (n < DN_MIN_TABLE)
 827                 return NULL;
 828
 829         if (n > DN_NUM_TABLES)
 830                 return NULL;
 831
 832         if (dn_fib_tables[n])
 833                 return dn_fib_tables[n];
 834
 835         if (!create)
 836                 return NULL;
 837
 838         if (in_interrupt() && net_ratelimit()) {
 839                 printk(KERN_DEBUG "DECnet: BUG! Attempt to create routing table from interrupt\n");
 840                 return NULL;
 841         }
 842         if ((t = kmalloc(sizeof(struct dn_fib_table), GFP_KERNEL)) == NULL)
 843                 return NULL;
 844
 845         memset(t, 0, sizeof(struct dn_fib_table));
 846
 847         t->n = n;
 848         t->insert = dn_fib_table_insert;
 849         t->delete = dn_fib_table_delete;
 850         t->lookup = dn_fib_table_lookup;
 851         t->flush  = dn_fib_table_flush;
 852 #ifdef CONFIG_PROC_FS
 853         t->get_info = dn_fib_table_get_info;
 854 #endif
 855         t->dump = dn_fib_table_dump;
 856         dn_fib_tables[n] = t;
 857
 858         return t;
 859 }
 860
 861 static void dn_fib_del_tree(int n)
 862 {
 863         struct dn_fib_table *t;
 864
 865         write_lock(&dn_fib_tables_lock);
 866         t = dn_fib_tables[n];
 867         dn_fib_tables[n] = NULL;
 868         write_unlock(&dn_fib_tables_lock);
 869
 870         if (t) {
 871                 kfree(t);
 872         }
 873 }
 874
 875 struct dn_fib_table *dn_fib_empty_table(void)
 876 {
 877         int id;
 878
 879         for(id = DN_MIN_TABLE; id <= DN_NUM_TABLES; id++)
 880                 if (dn_fib_tables[id] == NULL)
 881                         return dn_fib_get_table(id, 1);
 882         return NULL;
 883 }
 884
 885 void __init dn_fib_table_init(void)
 886 {
 887         dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
 888                                         sizeof(struct dn_fib_info),
 889                                         0, SLAB_HWCACHE_ALIGN,
 890                                         NULL, NULL);
 891 }
 892
 893 void __exit dn_fib_table_cleanup(void)
 894 {
 895         int i;
 896
 897         for (i = 0; i < DN_NUM_TABLES + 1; ++i)
 898                 dn_fib_del_tree(i);
 899
 900         return;
 901 }