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