net/decnet/dn_fib.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 (Glue/Info List)
   7  *
   8  * Author:      Steve Whitehouse <SteveW@ACM.org>
   9  *
  10  *
  11  * Changes:
  12  *              Alexey Kuznetsov : SMP locking changes
  13  *              Steve Whitehouse : Rewrote it... Well to be more correct, I
  14  *                                 copied most of it from the ipv4 fib code.
  15  *              Steve Whitehouse : Updated it in style and fixed a few bugs
  16  *                                 which were fixed in the ipv4 code since
  17  *                                 this code was copied from it.
  18  *
  19  */
  20 #include <linux/string.h>
  21 #include <linux/net.h>
  22 #include <linux/socket.h>
  23 #include <linux/slab.h>
  24 #include <linux/sockios.h>
  25 #include <linux/init.h>
  26 #include <linux/skbuff.h>
  27 #include <linux/netlink.h>
  28 #include <linux/rtnetlink.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/netdevice.h>
  31 #include <linux/timer.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/atomic.h>
  34 #include <asm/uaccess.h>
  35 #include <net/neighbour.h>
  36 #include <net/dst.h>
  37 #include <net/flow.h>
  38 #include <net/fib_rules.h>
  39 #include <net/dn.h>
  40 #include <net/dn_route.h>
  41 #include <net/dn_fib.h>
  42 #include <net/dn_neigh.h>
  43 #include <net/dn_dev.h>
  44
  45 #define RT_MIN_TABLE 1
  46
  47 #define for_fib_info() { struct dn_fib_info *fi;\
  48         for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
  49 #define endfor_fib_info() }
  50
  51 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
  52         for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
  53
  54 #define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
  55         for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
  56
  57 #define endfor_nexthops(fi) }
  58
  59 static DEFINE_SPINLOCK(dn_fib_multipath_lock);
  60 static struct dn_fib_info *dn_fib_info_list;
  61 static DEFINE_SPINLOCK(dn_fib_info_lock);
  62
  63 static struct
  64 {
  65         int error;
  66         u8 scope;
  67 } dn_fib_props[RTN_MAX+1] = {
  68         [RTN_UNSPEC] =      { .error = 0,       .scope = RT_SCOPE_NOWHERE },
  69         [RTN_UNICAST] =     { .error = 0,       .scope = RT_SCOPE_UNIVERSE },
  70         [RTN_LOCAL] =       { .error = 0,       .scope = RT_SCOPE_HOST },
  71         [RTN_BROADCAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  72         [RTN_ANYCAST] =     { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  73         [RTN_MULTICAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  74         [RTN_BLACKHOLE] =   { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
  75         [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
  76         [RTN_PROHIBIT] =    { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
  77         [RTN_THROW] =       { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
  78         [RTN_NAT] =         { .error = 0,       .scope = RT_SCOPE_NOWHERE },
  79         [RTN_XRESOLVE] =    { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  80 };
  81
  82 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
  83 static int dn_fib_sync_up(struct net_device *dev);
  84
  85 void dn_fib_free_info(struct dn_fib_info *fi)
  86 {
  87         if (fi->fib_dead == 0) {
  88                 printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
  89                 return;
  90         }
  91
  92         change_nexthops(fi) {
  93                 if (nh->nh_dev)
  94                         dev_put(nh->nh_dev);
  95                 nh->nh_dev = NULL;
  96         } endfor_nexthops(fi);
  97         kfree(fi);
  98 }
  99
 100 void dn_fib_release_info(struct dn_fib_info *fi)
 101 {
 102         spin_lock(&dn_fib_info_lock);
 103         if (fi && --fi->fib_treeref == 0) {
 104                 if (fi->fib_next)
 105                         fi->fib_next->fib_prev = fi->fib_prev;
 106                 if (fi->fib_prev)
 107                         fi->fib_prev->fib_next = fi->fib_next;
 108                 if (fi == dn_fib_info_list)
 109                         dn_fib_info_list = fi->fib_next;
 110                 fi->fib_dead = 1;
 111                 dn_fib_info_put(fi);
 112         }
 113         spin_unlock(&dn_fib_info_lock);
 114 }
 115
 116 static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
 117 {
 118         const struct dn_fib_nh *onh = ofi->fib_nh;
 119
 120         for_nexthops(fi) {
 121                 if (nh->nh_oif != onh->nh_oif ||
 122                         nh->nh_gw != onh->nh_gw ||
 123                         nh->nh_scope != onh->nh_scope ||
 124                         nh->nh_weight != onh->nh_weight ||
 125                         ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
 126                                 return -1;
 127                 onh++;
 128         } endfor_nexthops(fi);
 129         return 0;
 130 }
 131
 132 static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
 133 {
 134         for_fib_info() {
 135                 if (fi->fib_nhs != nfi->fib_nhs)
 136                         continue;
 137                 if (nfi->fib_protocol == fi->fib_protocol &&
 138                         nfi->fib_prefsrc == fi->fib_prefsrc &&
 139                         nfi->fib_priority == fi->fib_priority &&
 140                         memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
 141                         ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
 142                         (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
 143                                 return fi;
 144         } endfor_fib_info();
 145         return NULL;
 146 }
 147
 148 __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
 149 {
 150         while(RTA_OK(attr,attrlen)) {
 151                 if (attr->rta_type == type)
 152                         return *(__le16*)RTA_DATA(attr);
 153                 attr = RTA_NEXT(attr, attrlen);
 154         }
 155
 156         return 0;
 157 }
 158
 159 static int dn_fib_count_nhs(struct rtattr *rta)
 160 {
 161         int nhs = 0;
 162         struct rtnexthop *nhp = RTA_DATA(rta);
 163         int nhlen = RTA_PAYLOAD(rta);
 164
 165         while(nhlen >= (int)sizeof(struct rtnexthop)) {
 166                 if ((nhlen -= nhp->rtnh_len) < 0)
 167                         return 0;
 168                 nhs++;
 169                 nhp = RTNH_NEXT(nhp);
 170         }
 171
 172         return nhs;
 173 }
 174
 175 static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
 176 {
 177         struct rtnexthop *nhp = RTA_DATA(rta);
 178         int nhlen = RTA_PAYLOAD(rta);
 179
 180         change_nexthops(fi) {
 181                 int attrlen = nhlen - sizeof(struct rtnexthop);
 182                 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
 183                         return -EINVAL;
 184
 185                 nh->nh_flags  = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
 186                 nh->nh_oif    = nhp->rtnh_ifindex;
 187                 nh->nh_weight = nhp->rtnh_hops + 1;
 188
 189                 if (attrlen) {
 190                         nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
 191                 }
 192                 nhp = RTNH_NEXT(nhp);
 193         } endfor_nexthops(fi);
 194
 195         return 0;
 196 }
 197
 198
 199 static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
 200 {
 201         int err;
 202
 203         if (nh->nh_gw) {
 204                 struct flowidn fld;
 205                 struct dn_fib_res res;
 206
 207                 if (nh->nh_flags&RTNH_F_ONLINK) {
 208                         struct net_device *dev;
 209
 210                         if (r->rtm_scope >= RT_SCOPE_LINK)
 211                                 return -EINVAL;
 212                         if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST)
 213                                 return -EINVAL;
 214                         if ((dev = __dev_get_by_index(&init_net, nh->nh_oif)) == NULL)
 215                                 return -ENODEV;
 216                         if (!(dev->flags&IFF_UP))
 217                                 return -ENETDOWN;
 218                         nh->nh_dev = dev;
 219                         dev_hold(dev);
 220                         nh->nh_scope = RT_SCOPE_LINK;
 221                         return 0;
 222                 }
 223
 224                 memset(&fld, 0, sizeof(fld));
 225                 fld.daddr = nh->nh_gw;
 226                 fld.flowidn_oif = nh->nh_oif;
 227                 fld.flowidn_scope = r->rtm_scope + 1;
 228
 229                 if (fld.flowidn_scope < RT_SCOPE_LINK)
 230                         fld.flowidn_scope = RT_SCOPE_LINK;
 231
 232                 if ((err = dn_fib_lookup(&fld, &res)) != 0)
 233                         return err;
 234
 235                 err = -EINVAL;
 236                 if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
 237                         goto out;
 238                 nh->nh_scope = res.scope;
 239                 nh->nh_oif = DN_FIB_RES_OIF(res);
 240                 nh->nh_dev = DN_FIB_RES_DEV(res);
 241                 if (nh->nh_dev == NULL)
 242                         goto out;
 243                 dev_hold(nh->nh_dev);
 244                 err = -ENETDOWN;
 245                 if (!(nh->nh_dev->flags & IFF_UP))
 246                         goto out;
 247                 err = 0;
 248 out:
 249                 dn_fib_res_put(&res);
 250                 return err;
 251         } else {
 252                 struct net_device *dev;
 253
 254                 if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
 255                         return -EINVAL;
 256
 257                 dev = __dev_get_by_index(&init_net, nh->nh_oif);
 258                 if (dev == NULL || dev->dn_ptr == NULL)
 259                         return -ENODEV;
 260                 if (!(dev->flags&IFF_UP))
 261                         return -ENETDOWN;
 262                 nh->nh_dev = dev;
 263                 dev_hold(nh->nh_dev);
 264                 nh->nh_scope = RT_SCOPE_HOST;
 265         }
 266
 267         return 0;
 268 }
 269
 270
 271 struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
 272 {
 273         int err;
 274         struct dn_fib_info *fi = NULL;
 275         struct dn_fib_info *ofi;
 276         int nhs = 1;
 277
 278         if (r->rtm_type > RTN_MAX)
 279                 goto err_inval;
 280
 281         if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
 282                 goto err_inval;
 283
 284         if (rta->rta_mp) {
 285                 nhs = dn_fib_count_nhs(rta->rta_mp);
 286                 if (nhs == 0)
 287                         goto err_inval;
 288         }
 289
 290         fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
 291         err = -ENOBUFS;
 292         if (fi == NULL)
 293                 goto failure;
 294
 295         fi->fib_protocol = r->rtm_protocol;
 296         fi->fib_nhs = nhs;
 297         fi->fib_flags = r->rtm_flags;
 298         if (rta->rta_priority)
 299                 fi->fib_priority = *rta->rta_priority;
 300         if (rta->rta_mx) {
 301                 int attrlen = RTA_PAYLOAD(rta->rta_mx);
 302                 struct rtattr *attr = RTA_DATA(rta->rta_mx);
 303
 304                 while(RTA_OK(attr, attrlen)) {
 305                         unsigned int flavour = attr->rta_type;
 306
 307                         if (flavour) {
 308                                 if (flavour > RTAX_MAX)
 309                                         goto err_inval;
 310                                 fi->fib_metrics[flavour-1] = *(unsigned int *)RTA_DATA(attr);
 311                         }
 312                         attr = RTA_NEXT(attr, attrlen);
 313                 }
 314         }
 315         if (rta->rta_prefsrc)
 316                 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
 317
 318         if (rta->rta_mp) {
 319                 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
 320                         goto failure;
 321                 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
 322                         goto err_inval;
 323                 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
 324                         goto err_inval;
 325         } else {
 326                 struct dn_fib_nh *nh = fi->fib_nh;
 327                 if (rta->rta_oif)
 328                         nh->nh_oif = *rta->rta_oif;
 329                 if (rta->rta_gw)
 330                         memcpy(&nh->nh_gw, rta->rta_gw, 2);
 331                 nh->nh_flags = r->rtm_flags;
 332                 nh->nh_weight = 1;
 333         }
 334
 335         if (r->rtm_type == RTN_NAT) {
 336                 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
 337                         goto err_inval;
 338                 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
 339                 goto link_it;
 340         }
 341
 342         if (dn_fib_props[r->rtm_type].error) {
 343                 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
 344                         goto err_inval;
 345                 goto link_it;
 346         }
 347
 348         if (r->rtm_scope > RT_SCOPE_HOST)
 349                 goto err_inval;
 350
 351         if (r->rtm_scope == RT_SCOPE_HOST) {
 352                 struct dn_fib_nh *nh = fi->fib_nh;
 353
 354                 /* Local address is added */
 355                 if (nhs != 1 || nh->nh_gw)
 356                         goto err_inval;
 357                 nh->nh_scope = RT_SCOPE_NOWHERE;
 358                 nh->nh_dev = dev_get_by_index(&init_net, fi->fib_nh->nh_oif);
 359                 err = -ENODEV;
 360                 if (nh->nh_dev == NULL)
 361                         goto failure;
 362         } else {
 363                 change_nexthops(fi) {
 364                         if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
 365                                 goto failure;
 366                 } endfor_nexthops(fi)
 367         }
 368
 369         if (fi->fib_prefsrc) {
 370                 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
 371                     memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
 372                         if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
 373                                 goto err_inval;
 374         }
 375
 376 link_it:
 377         if ((ofi = dn_fib_find_info(fi)) != NULL) {
 378                 fi->fib_dead = 1;
 379                 dn_fib_free_info(fi);
 380                 ofi->fib_treeref++;
 381                 return ofi;
 382         }
 383
 384         fi->fib_treeref++;
 385         atomic_inc(&fi->fib_clntref);
 386         spin_lock(&dn_fib_info_lock);
 387         fi->fib_next = dn_fib_info_list;
 388         fi->fib_prev = NULL;
 389         if (dn_fib_info_list)
 390                 dn_fib_info_list->fib_prev = fi;
 391         dn_fib_info_list = fi;
 392         spin_unlock(&dn_fib_info_lock);
 393         return fi;
 394
 395 err_inval:
 396         err = -EINVAL;
 397
 398 failure:
 399         *errp = err;
 400         if (fi) {
 401                 fi->fib_dead = 1;
 402                 dn_fib_free_info(fi);
 403         }
 404
 405         return NULL;
 406 }
 407
 408 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn *fld, struct dn_fib_res *res)
 409 {
 410         int err = dn_fib_props[type].error;
 411
 412         if (err == 0) {
 413                 if (fi->fib_flags & RTNH_F_DEAD)
 414                         return 1;
 415
 416                 res->fi = fi;
 417
 418                 switch (type) {
 419                 case RTN_NAT:
 420                         DN_FIB_RES_RESET(*res);
 421                         atomic_inc(&fi->fib_clntref);
 422                         return 0;
 423                 case RTN_UNICAST:
 424                 case RTN_LOCAL:
 425                         for_nexthops(fi) {
 426                                 if (nh->nh_flags & RTNH_F_DEAD)
 427                                         continue;
 428                                 if (!fld->flowidn_oif ||
 429                                     fld->flowidn_oif == nh->nh_oif)
 430                                         break;
 431                         }
 432                         if (nhsel < fi->fib_nhs) {
 433                                 res->nh_sel = nhsel;
 434                                 atomic_inc(&fi->fib_clntref);
 435                                 return 0;
 436                         }
 437                         endfor_nexthops(fi);
 438                         res->fi = NULL;
 439                         return 1;
 440                 default:
 441                         net_err_ratelimited("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n",
 442                                             type);
 443                         res->fi = NULL;
 444                         return -EINVAL;
 445                 }
 446         }
 447         return err;
 448 }
 449
 450 void dn_fib_select_multipath(const struct flowidn *fld, struct dn_fib_res *res)
 451 {
 452         struct dn_fib_info *fi = res->fi;
 453         int w;
 454
 455         spin_lock_bh(&dn_fib_multipath_lock);
 456         if (fi->fib_power <= 0) {
 457                 int power = 0;
 458                 change_nexthops(fi) {
 459                         if (!(nh->nh_flags&RTNH_F_DEAD)) {
 460                                 power += nh->nh_weight;
 461                                 nh->nh_power = nh->nh_weight;
 462                         }
 463                 } endfor_nexthops(fi);
 464                 fi->fib_power = power;
 465                 if (power < 0) {
 466                         spin_unlock_bh(&dn_fib_multipath_lock);
 467                         res->nh_sel = 0;
 468                         return;
 469                 }
 470         }
 471
 472         w = jiffies % fi->fib_power;
 473
 474         change_nexthops(fi) {
 475                 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
 476                         if ((w -= nh->nh_power) <= 0) {
 477                                 nh->nh_power--;
 478                                 fi->fib_power--;
 479                                 res->nh_sel = nhsel;
 480                                 spin_unlock_bh(&dn_fib_multipath_lock);
 481                                 return;
 482                         }
 483                 }
 484         } endfor_nexthops(fi);
 485         res->nh_sel = 0;
 486         spin_unlock_bh(&dn_fib_multipath_lock);
 487 }
 488
 489
 490 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
 491 {
 492         int i;
 493
 494         for(i = 1; i <= RTA_MAX; i++) {
 495                 struct rtattr *attr = rta[i-1];
 496                 if (attr) {
 497                         if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
 498                                 return -EINVAL;
 499                         if (i != RTA_MULTIPATH && i != RTA_METRICS &&
 500                             i != RTA_TABLE)
 501                                 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
 502                 }
 503         }
 504
 505         return 0;
 506 }
 507
 508 static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 509 {
 510         struct net *net = sock_net(skb->sk);
 511         struct dn_fib_table *tb;
 512         struct rtattr **rta = arg;
 513         struct rtmsg *r = NLMSG_DATA(nlh);
 514
 515         if (!net_eq(net, &init_net))
 516                 return -EINVAL;
 517
 518         if (dn_fib_check_attr(r, rta))
 519                 return -EINVAL;
 520
 521         tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
 522         if (tb)
 523                 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
 524
 525         return -ESRCH;
 526 }
 527
 528 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 529 {
 530         struct net *net = sock_net(skb->sk);
 531         struct dn_fib_table *tb;
 532         struct rtattr **rta = arg;
 533         struct rtmsg *r = NLMSG_DATA(nlh);
 534
 535         if (!net_eq(net, &init_net))
 536                 return -EINVAL;
 537
 538         if (dn_fib_check_attr(r, rta))
 539                 return -EINVAL;
 540
 541         tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
 542         if (tb)
 543                 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
 544
 545         return -ENOBUFS;
 546 }
 547
 548 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
 549 {
 550         struct dn_fib_table *tb;
 551         struct {
 552                 struct nlmsghdr nlh;
 553                 struct rtmsg rtm;
 554         } req;
 555         struct dn_kern_rta rta;
 556
 557         memset(&req.rtm, 0, sizeof(req.rtm));
 558         memset(&rta, 0, sizeof(rta));
 559
 560         if (type == RTN_UNICAST)
 561                 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
 562         else
 563                 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
 564
 565         if (tb == NULL)
 566                 return;
 567
 568         req.nlh.nlmsg_len = sizeof(req);
 569         req.nlh.nlmsg_type = cmd;
 570         req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
 571         req.nlh.nlmsg_pid = 0;
 572         req.nlh.nlmsg_seq = 0;
 573
 574         req.rtm.rtm_dst_len = dst_len;
 575         req.rtm.rtm_table = tb->n;
 576         req.rtm.rtm_protocol = RTPROT_KERNEL;
 577         req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
 578         req.rtm.rtm_type = type;
 579
 580         rta.rta_dst = &dst;
 581         rta.rta_prefsrc = &ifa->ifa_local;
 582         rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
 583
 584         if (cmd == RTM_NEWROUTE)
 585                 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
 586         else
 587                 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
 588 }
 589
 590 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
 591 {
 592
 593         fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
 594
 595 #if 0
 596         if (!(dev->flags&IFF_UP))
 597                 return;
 598         /* In the future, we will want to add default routes here */
 599
 600 #endif
 601 }
 602
 603 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
 604 {
 605         int found_it = 0;
 606         struct net_device *dev;
 607         struct dn_dev *dn_db;
 608         struct dn_ifaddr *ifa2;
 609
 610         ASSERT_RTNL();
 611
 612         /* Scan device list */
 613         rcu_read_lock();
 614         for_each_netdev_rcu(&init_net, dev) {
 615                 dn_db = rcu_dereference(dev->dn_ptr);
 616                 if (dn_db == NULL)
 617                         continue;
 618                 for (ifa2 = rcu_dereference(dn_db->ifa_list);
 619                      ifa2 != NULL;
 620                      ifa2 = rcu_dereference(ifa2->ifa_next)) {
 621                         if (ifa2->ifa_local == ifa->ifa_local) {
 622                                 found_it = 1;
 623                                 break;
 624                         }
 625                 }
 626         }
 627         rcu_read_unlock();
 628
 629         if (found_it == 0) {
 630                 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
 631
 632                 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
 633                         if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
 634                                 dn_fib_flush();
 635                 }
 636         }
 637 }
 638
 639 static void dn_fib_disable_addr(struct net_device *dev, int force)
 640 {
 641         if (dn_fib_sync_down(0, dev, force))
 642                 dn_fib_flush();
 643         dn_rt_cache_flush(0);
 644         neigh_ifdown(&dn_neigh_table, dev);
 645 }
 646
 647 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
 648 {
 649         struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
 650
 651         switch (event) {
 652         case NETDEV_UP:
 653                 dn_fib_add_ifaddr(ifa);
 654                 dn_fib_sync_up(ifa->ifa_dev->dev);
 655                 dn_rt_cache_flush(-1);
 656                 break;
 657         case NETDEV_DOWN:
 658                 dn_fib_del_ifaddr(ifa);
 659                 if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
 660                         dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
 661                 } else {
 662                         dn_rt_cache_flush(-1);
 663                 }
 664                 break;
 665         }
 666         return NOTIFY_DONE;
 667 }
 668
 669 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
 670 {
 671         int ret = 0;
 672         int scope = RT_SCOPE_NOWHERE;
 673
 674         if (force)
 675                 scope = -1;
 676
 677         for_fib_info() {
 678                 /*
 679                  * This makes no sense for DECnet.... we will almost
 680                  * certainly have more than one local address the same
 681                  * over all our interfaces. It needs thinking about
 682                  * some more.
 683                  */
 684                 if (local && fi->fib_prefsrc == local) {
 685                         fi->fib_flags |= RTNH_F_DEAD;
 686                         ret++;
 687                 } else if (dev && fi->fib_nhs) {
 688                         int dead = 0;
 689
 690                         change_nexthops(fi) {
 691                                 if (nh->nh_flags&RTNH_F_DEAD)
 692                                         dead++;
 693                                 else if (nh->nh_dev == dev &&
 694                                                 nh->nh_scope != scope) {
 695                                         spin_lock_bh(&dn_fib_multipath_lock);
 696                                         nh->nh_flags |= RTNH_F_DEAD;
 697                                         fi->fib_power -= nh->nh_power;
 698                                         nh->nh_power = 0;
 699                                         spin_unlock_bh(&dn_fib_multipath_lock);
 700                                         dead++;
 701                                 }
 702                         } endfor_nexthops(fi)
 703                         if (dead == fi->fib_nhs) {
 704                                 fi->fib_flags |= RTNH_F_DEAD;
 705                                 ret++;
 706                         }
 707                 }
 708         } endfor_fib_info();
 709         return ret;
 710 }
 711
 712
 713 static int dn_fib_sync_up(struct net_device *dev)
 714 {
 715         int ret = 0;
 716
 717         if (!(dev->flags&IFF_UP))
 718                 return 0;
 719
 720         for_fib_info() {
 721                 int alive = 0;
 722
 723                 change_nexthops(fi) {
 724                         if (!(nh->nh_flags&RTNH_F_DEAD)) {
 725                                 alive++;
 726                                 continue;
 727                         }
 728                         if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
 729                                 continue;
 730                         if (nh->nh_dev != dev || dev->dn_ptr == NULL)
 731                                 continue;
 732                         alive++;
 733                         spin_lock_bh(&dn_fib_multipath_lock);
 734                         nh->nh_power = 0;
 735                         nh->nh_flags &= ~RTNH_F_DEAD;
 736                         spin_unlock_bh(&dn_fib_multipath_lock);
 737                 } endfor_nexthops(fi);
 738
 739                 if (alive > 0) {
 740                         fi->fib_flags &= ~RTNH_F_DEAD;
 741                         ret++;
 742                 }
 743         } endfor_fib_info();
 744         return ret;
 745 }
 746
 747 static struct notifier_block dn_fib_dnaddr_notifier = {
 748         .notifier_call = dn_fib_dnaddr_event,
 749 };
 750
 751 void __exit dn_fib_cleanup(void)
 752 {
 753         dn_fib_table_cleanup();
 754         dn_fib_rules_cleanup();
 755
 756         unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
 757 }
 758
 759
 760 void __init dn_fib_init(void)
 761 {
 762         dn_fib_table_init();
 763         dn_fib_rules_init();
 764
 765         register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
 766
 767         rtnl_register(PF_DECnet, RTM_NEWROUTE, dn_fib_rtm_newroute, NULL, NULL);
 768         rtnl_register(PF_DECnet, RTM_DELROUTE, dn_fib_rtm_delroute, NULL, NULL);
 769 }
 770
 771