linux/net/decnet/dn_fib.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * DECnet       An implementation of the DECnet protocol suite for the LINUX
   4 *              operating system.  DECnet is implemented using the  BSD Socket
   5 *              interface as the means of communication with the user level.
   6 *
   7 *              DECnet Routing Forwarding Information Base (Glue/Info List)
   8 *
   9 * Author:      Steve Whitehouse <SteveW@ACM.org>
  10 *
  11 *
  12 * Changes:
  13 *              Alexey Kuznetsov : SMP locking changes
  14 *              Steve Whitehouse : Rewrote it... Well to be more correct, I
  15 *                                 copied most of it from the ipv4 fib code.
  16 *              Steve Whitehouse : Updated it in style and fixed a few bugs
  17 *                                 which were fixed in the ipv4 code since
  18 *                                 this code was copied from it.
  19 *
  20 */
  21#include <linux/string.h>
  22#include <linux/net.h>
  23#include <linux/socket.h>
  24#include <linux/slab.h>
  25#include <linux/sockios.h>
  26#include <linux/init.h>
  27#include <linux/skbuff.h>
  28#include <linux/netlink.h>
  29#include <linux/rtnetlink.h>
  30#include <linux/proc_fs.h>
  31#include <linux/netdevice.h>
  32#include <linux/timer.h>
  33#include <linux/spinlock.h>
  34#include <linux/atomic.h>
  35#include <linux/uaccess.h>
  36#include <net/neighbour.h>
  37#include <net/dst.h>
  38#include <net/flow.h>
  39#include <net/fib_rules.h>
  40#include <net/dn.h>
  41#include <net/dn_route.h>
  42#include <net/dn_fib.h>
  43#include <net/dn_neigh.h>
  44#include <net/dn_dev.h>
  45#include <net/rtnh.h>
  46
  47#define RT_MIN_TABLE 1
  48
  49#define for_fib_info() { struct dn_fib_info *fi;\
  50        for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
  51#define endfor_fib_info() }
  52
  53#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
  54        for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
  55
  56#define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
  57        for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
  58
  59#define endfor_nexthops(fi) }
  60
  61static DEFINE_SPINLOCK(dn_fib_multipath_lock);
  62static struct dn_fib_info *dn_fib_info_list;
  63static DEFINE_SPINLOCK(dn_fib_info_lock);
  64
  65static struct
  66{
  67        int error;
  68        u8 scope;
  69} dn_fib_props[RTN_MAX+1] = {
  70        [RTN_UNSPEC] =      { .error = 0,       .scope = RT_SCOPE_NOWHERE },
  71        [RTN_UNICAST] =     { .error = 0,       .scope = RT_SCOPE_UNIVERSE },
  72        [RTN_LOCAL] =       { .error = 0,       .scope = RT_SCOPE_HOST },
  73        [RTN_BROADCAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  74        [RTN_ANYCAST] =     { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  75        [RTN_MULTICAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  76        [RTN_BLACKHOLE] =   { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
  77        [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
  78        [RTN_PROHIBIT] =    { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
  79        [RTN_THROW] =       { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
  80        [RTN_NAT] =         { .error = 0,       .scope = RT_SCOPE_NOWHERE },
  81        [RTN_XRESOLVE] =    { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
  82};
  83
  84static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
  85static int dn_fib_sync_up(struct net_device *dev);
  86
  87void dn_fib_free_info(struct dn_fib_info *fi)
  88{
  89        if (fi->fib_dead == 0) {
  90                printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
  91                return;
  92        }
  93
  94        change_nexthops(fi) {
  95                if (nh->nh_dev)
  96                        dev_put(nh->nh_dev);
  97                nh->nh_dev = NULL;
  98        } endfor_nexthops(fi);
  99        kfree(fi);
 100}
 101
 102void dn_fib_release_info(struct dn_fib_info *fi)
 103{
 104        spin_lock(&dn_fib_info_lock);
 105        if (fi && --fi->fib_treeref == 0) {
 106                if (fi->fib_next)
 107                        fi->fib_next->fib_prev = fi->fib_prev;
 108                if (fi->fib_prev)
 109                        fi->fib_prev->fib_next = fi->fib_next;
 110                if (fi == dn_fib_info_list)
 111                        dn_fib_info_list = fi->fib_next;
 112                fi->fib_dead = 1;
 113                dn_fib_info_put(fi);
 114        }
 115        spin_unlock(&dn_fib_info_lock);
 116}
 117
 118static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
 119{
 120        const struct dn_fib_nh *onh = ofi->fib_nh;
 121
 122        for_nexthops(fi) {
 123                if (nh->nh_oif != onh->nh_oif ||
 124                        nh->nh_gw != onh->nh_gw ||
 125                        nh->nh_scope != onh->nh_scope ||
 126                        nh->nh_weight != onh->nh_weight ||
 127                        ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
 128                                return -1;
 129                onh++;
 130        } endfor_nexthops(fi);
 131        return 0;
 132}
 133
 134static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
 135{
 136        for_fib_info() {
 137                if (fi->fib_nhs != nfi->fib_nhs)
 138                        continue;
 139                if (nfi->fib_protocol == fi->fib_protocol &&
 140                        nfi->fib_prefsrc == fi->fib_prefsrc &&
 141                        nfi->fib_priority == fi->fib_priority &&
 142                        memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
 143                        ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
 144                        (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
 145                                return fi;
 146        } endfor_fib_info();
 147        return NULL;
 148}
 149
 150static int dn_fib_count_nhs(const struct nlattr *attr)
 151{
 152        struct rtnexthop *nhp = nla_data(attr);
 153        int nhs = 0, nhlen = nla_len(attr);
 154
 155        while (rtnh_ok(nhp, nhlen)) {
 156                nhs++;
 157                nhp = rtnh_next(nhp, &nhlen);
 158        }
 159
 160        /* leftover implies invalid nexthop configuration, discard it */
 161        return nhlen > 0 ? 0 : nhs;
 162}
 163
 164static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct nlattr *attr,
 165                          const struct rtmsg *r)
 166{
 167        struct rtnexthop *nhp = nla_data(attr);
 168        int nhlen = nla_len(attr);
 169
 170        change_nexthops(fi) {
 171                int attrlen;
 172
 173                if (!rtnh_ok(nhp, nhlen))
 174                        return -EINVAL;
 175
 176                nh->nh_flags  = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
 177                nh->nh_oif    = nhp->rtnh_ifindex;
 178                nh->nh_weight = nhp->rtnh_hops + 1;
 179
 180                attrlen = rtnh_attrlen(nhp);
 181                if (attrlen > 0) {
 182                        struct nlattr *gw_attr;
 183
 184                        gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
 185                        nh->nh_gw = gw_attr ? nla_get_le16(gw_attr) : 0;
 186                }
 187
 188                nhp = rtnh_next(nhp, &nhlen);
 189        } endfor_nexthops(fi);
 190
 191        return 0;
 192}
 193
 194
 195static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
 196{
 197        int err;
 198
 199        if (nh->nh_gw) {
 200                struct flowidn fld;
 201                struct dn_fib_res res;
 202
 203                if (nh->nh_flags&RTNH_F_ONLINK) {
 204                        struct net_device *dev;
 205
 206                        if (r->rtm_scope >= RT_SCOPE_LINK)
 207                                return -EINVAL;
 208                        if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST)
 209                                return -EINVAL;
 210                        if ((dev = __dev_get_by_index(&init_net, nh->nh_oif)) == NULL)
 211                                return -ENODEV;
 212                        if (!(dev->flags&IFF_UP))
 213                                return -ENETDOWN;
 214                        nh->nh_dev = dev;
 215                        dev_hold(dev);
 216                        nh->nh_scope = RT_SCOPE_LINK;
 217                        return 0;
 218                }
 219
 220                memset(&fld, 0, sizeof(fld));
 221                fld.daddr = nh->nh_gw;
 222                fld.flowidn_oif = nh->nh_oif;
 223                fld.flowidn_scope = r->rtm_scope + 1;
 224
 225                if (fld.flowidn_scope < RT_SCOPE_LINK)
 226                        fld.flowidn_scope = RT_SCOPE_LINK;
 227
 228                if ((err = dn_fib_lookup(&fld, &res)) != 0)
 229                        return err;
 230
 231                err = -EINVAL;
 232                if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
 233                        goto out;
 234                nh->nh_scope = res.scope;
 235                nh->nh_oif = DN_FIB_RES_OIF(res);
 236                nh->nh_dev = DN_FIB_RES_DEV(res);
 237                if (nh->nh_dev == NULL)
 238                        goto out;
 239                dev_hold(nh->nh_dev);
 240                err = -ENETDOWN;
 241                if (!(nh->nh_dev->flags & IFF_UP))
 242                        goto out;
 243                err = 0;
 244out:
 245                dn_fib_res_put(&res);
 246                return err;
 247        } else {
 248                struct net_device *dev;
 249
 250                if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
 251                        return -EINVAL;
 252
 253                dev = __dev_get_by_index(&init_net, nh->nh_oif);
 254                if (dev == NULL || dev->dn_ptr == NULL)
 255                        return -ENODEV;
 256                if (!(dev->flags&IFF_UP))
 257                        return -ENETDOWN;
 258                nh->nh_dev = dev;
 259                dev_hold(nh->nh_dev);
 260                nh->nh_scope = RT_SCOPE_HOST;
 261        }
 262
 263        return 0;
 264}
 265
 266
 267struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct nlattr *attrs[],
 268                                       const struct nlmsghdr *nlh, int *errp)
 269{
 270        int err;
 271        struct dn_fib_info *fi = NULL;
 272        struct dn_fib_info *ofi;
 273        int nhs = 1;
 274
 275        if (r->rtm_type > RTN_MAX)
 276                goto err_inval;
 277
 278        if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
 279                goto err_inval;
 280
 281        if (attrs[RTA_MULTIPATH] &&
 282            (nhs = dn_fib_count_nhs(attrs[RTA_MULTIPATH])) == 0)
 283                goto err_inval;
 284
 285        fi = kzalloc(struct_size(fi, fib_nh, nhs), GFP_KERNEL);
 286        err = -ENOBUFS;
 287        if (fi == NULL)
 288                goto failure;
 289
 290        fi->fib_protocol = r->rtm_protocol;
 291        fi->fib_nhs = nhs;
 292        fi->fib_flags = r->rtm_flags;
 293
 294        if (attrs[RTA_PRIORITY])
 295                fi->fib_priority = nla_get_u32(attrs[RTA_PRIORITY]);
 296
 297        if (attrs[RTA_METRICS]) {
 298                struct nlattr *attr;
 299                int rem;
 300
 301                nla_for_each_nested(attr, attrs[RTA_METRICS], rem) {
 302                        int type = nla_type(attr);
 303
 304                        if (type) {
 305                                if (type > RTAX_MAX || type == RTAX_CC_ALGO ||
 306                                    nla_len(attr) < 4)
 307                                        goto err_inval;
 308
 309                                fi->fib_metrics[type-1] = nla_get_u32(attr);
 310                        }
 311                }
 312        }
 313
 314        if (attrs[RTA_PREFSRC])
 315                fi->fib_prefsrc = nla_get_le16(attrs[RTA_PREFSRC]);
 316
 317        if (attrs[RTA_MULTIPATH]) {
 318                if ((err = dn_fib_get_nhs(fi, attrs[RTA_MULTIPATH], r)) != 0)
 319                        goto failure;
 320
 321                if (attrs[RTA_OIF] &&
 322                    fi->fib_nh->nh_oif != nla_get_u32(attrs[RTA_OIF]))
 323                        goto err_inval;
 324
 325                if (attrs[RTA_GATEWAY] &&
 326                    fi->fib_nh->nh_gw != nla_get_le16(attrs[RTA_GATEWAY]))
 327                        goto err_inval;
 328        } else {
 329                struct dn_fib_nh *nh = fi->fib_nh;
 330
 331                if (attrs[RTA_OIF])
 332                        nh->nh_oif = nla_get_u32(attrs[RTA_OIF]);
 333
 334                if (attrs[RTA_GATEWAY])
 335                        nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]);
 336
 337                nh->nh_flags = r->rtm_flags;
 338                nh->nh_weight = 1;
 339        }
 340
 341        if (r->rtm_type == RTN_NAT) {
 342                if (!attrs[RTA_GATEWAY] || nhs != 1 || attrs[RTA_OIF])
 343                        goto err_inval;
 344
 345                fi->fib_nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]);
 346                goto link_it;
 347        }
 348
 349        if (dn_fib_props[r->rtm_type].error) {
 350                if (attrs[RTA_GATEWAY] || attrs[RTA_OIF] || attrs[RTA_MULTIPATH])
 351                        goto err_inval;
 352
 353                goto link_it;
 354        }
 355
 356        if (r->rtm_scope > RT_SCOPE_HOST)
 357                goto err_inval;
 358
 359        if (r->rtm_scope == RT_SCOPE_HOST) {
 360                struct dn_fib_nh *nh = fi->fib_nh;
 361
 362                /* Local address is added */
 363                if (nhs != 1 || nh->nh_gw)
 364                        goto err_inval;
 365                nh->nh_scope = RT_SCOPE_NOWHERE;
 366                nh->nh_dev = dev_get_by_index(&init_net, fi->fib_nh->nh_oif);
 367                err = -ENODEV;
 368                if (nh->nh_dev == NULL)
 369                        goto failure;
 370        } else {
 371                change_nexthops(fi) {
 372                        if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
 373                                goto failure;
 374                } endfor_nexthops(fi)
 375        }
 376
 377        if (fi->fib_prefsrc) {
 378                if (r->rtm_type != RTN_LOCAL || !attrs[RTA_DST] ||
 379                    fi->fib_prefsrc != nla_get_le16(attrs[RTA_DST]))
 380                        if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
 381                                goto err_inval;
 382        }
 383
 384link_it:
 385        if ((ofi = dn_fib_find_info(fi)) != NULL) {
 386                fi->fib_dead = 1;
 387                dn_fib_free_info(fi);
 388                ofi->fib_treeref++;
 389                return ofi;
 390        }
 391
 392        fi->fib_treeref++;
 393        refcount_set(&fi->fib_clntref, 1);
 394        spin_lock(&dn_fib_info_lock);
 395        fi->fib_next = dn_fib_info_list;
 396        fi->fib_prev = NULL;
 397        if (dn_fib_info_list)
 398                dn_fib_info_list->fib_prev = fi;
 399        dn_fib_info_list = fi;
 400        spin_unlock(&dn_fib_info_lock);
 401        return fi;
 402
 403err_inval:
 404        err = -EINVAL;
 405
 406failure:
 407        *errp = err;
 408        if (fi) {
 409                fi->fib_dead = 1;
 410                dn_fib_free_info(fi);
 411        }
 412
 413        return NULL;
 414}
 415
 416int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn *fld, struct dn_fib_res *res)
 417{
 418        int err = dn_fib_props[type].error;
 419
 420        if (err == 0) {
 421                if (fi->fib_flags & RTNH_F_DEAD)
 422                        return 1;
 423
 424                res->fi = fi;
 425
 426                switch (type) {
 427                case RTN_NAT:
 428                        DN_FIB_RES_RESET(*res);
 429                        refcount_inc(&fi->fib_clntref);
 430                        return 0;
 431                case RTN_UNICAST:
 432                case RTN_LOCAL:
 433                        for_nexthops(fi) {
 434                                if (nh->nh_flags & RTNH_F_DEAD)
 435                                        continue;
 436                                if (!fld->flowidn_oif ||
 437                                    fld->flowidn_oif == nh->nh_oif)
 438                                        break;
 439                        }
 440                        if (nhsel < fi->fib_nhs) {
 441                                res->nh_sel = nhsel;
 442                                refcount_inc(&fi->fib_clntref);
 443                                return 0;
 444                        }
 445                        endfor_nexthops(fi);
 446                        res->fi = NULL;
 447                        return 1;
 448                default:
 449                        net_err_ratelimited("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n",
 450                                            type);
 451                        res->fi = NULL;
 452                        return -EINVAL;
 453                }
 454        }
 455        return err;
 456}
 457
 458void dn_fib_select_multipath(const struct flowidn *fld, struct dn_fib_res *res)
 459{
 460        struct dn_fib_info *fi = res->fi;
 461        int w;
 462
 463        spin_lock_bh(&dn_fib_multipath_lock);
 464        if (fi->fib_power <= 0) {
 465                int power = 0;
 466                change_nexthops(fi) {
 467                        if (!(nh->nh_flags&RTNH_F_DEAD)) {
 468                                power += nh->nh_weight;
 469                                nh->nh_power = nh->nh_weight;
 470                        }
 471                } endfor_nexthops(fi);
 472                fi->fib_power = power;
 473                if (power < 0) {
 474                        spin_unlock_bh(&dn_fib_multipath_lock);
 475                        res->nh_sel = 0;
 476                        return;
 477                }
 478        }
 479
 480        w = jiffies % fi->fib_power;
 481
 482        change_nexthops(fi) {
 483                if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
 484                        if ((w -= nh->nh_power) <= 0) {
 485                                nh->nh_power--;
 486                                fi->fib_power--;
 487                                res->nh_sel = nhsel;
 488                                spin_unlock_bh(&dn_fib_multipath_lock);
 489                                return;
 490                        }
 491                }
 492        } endfor_nexthops(fi);
 493        res->nh_sel = 0;
 494        spin_unlock_bh(&dn_fib_multipath_lock);
 495}
 496
 497static inline u32 rtm_get_table(struct nlattr *attrs[], u8 table)
 498{
 499        if (attrs[RTA_TABLE])
 500                table = nla_get_u32(attrs[RTA_TABLE]);
 501
 502        return table;
 503}
 504
 505static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
 506                               struct netlink_ext_ack *extack)
 507{
 508        struct net *net = sock_net(skb->sk);
 509        struct dn_fib_table *tb;
 510        struct rtmsg *r = nlmsg_data(nlh);
 511        struct nlattr *attrs[RTA_MAX+1];
 512        int err;
 513
 514        if (!netlink_capable(skb, CAP_NET_ADMIN))
 515                return -EPERM;
 516
 517        if (!net_eq(net, &init_net))
 518                return -EINVAL;
 519
 520        err = nlmsg_parse_deprecated(nlh, sizeof(*r), attrs, RTA_MAX,
 521                                     rtm_dn_policy, extack);
 522        if (err < 0)
 523                return err;
 524
 525        tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 0);
 526        if (!tb)
 527                return -ESRCH;
 528
 529        return tb->delete(tb, r, attrs, nlh, &NETLINK_CB(skb));
 530}
 531
 532static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
 533                               struct netlink_ext_ack *extack)
 534{
 535        struct net *net = sock_net(skb->sk);
 536        struct dn_fib_table *tb;
 537        struct rtmsg *r = nlmsg_data(nlh);
 538        struct nlattr *attrs[RTA_MAX+1];
 539        int err;
 540
 541        if (!netlink_capable(skb, CAP_NET_ADMIN))
 542                return -EPERM;
 543
 544        if (!net_eq(net, &init_net))
 545                return -EINVAL;
 546
 547        err = nlmsg_parse_deprecated(nlh, sizeof(*r), attrs, RTA_MAX,
 548                                     rtm_dn_policy, extack);
 549        if (err < 0)
 550                return err;
 551
 552        tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 1);
 553        if (!tb)
 554                return -ENOBUFS;
 555
 556        return tb->insert(tb, r, attrs, nlh, &NETLINK_CB(skb));
 557}
 558
 559static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
 560{
 561        struct dn_fib_table *tb;
 562        struct {
 563                struct nlmsghdr nlh;
 564                struct rtmsg rtm;
 565        } req;
 566        struct {
 567                struct nlattr hdr;
 568                __le16 dst;
 569        } dst_attr = {
 570                .dst = dst,
 571        };
 572        struct {
 573                struct nlattr hdr;
 574                __le16 prefsrc;
 575        } prefsrc_attr = {
 576                .prefsrc = ifa->ifa_local,
 577        };
 578        struct {
 579                struct nlattr hdr;
 580                u32 oif;
 581        } oif_attr = {
 582                .oif = ifa->ifa_dev->dev->ifindex,
 583        };
 584        struct nlattr *attrs[RTA_MAX+1] = {
 585                [RTA_DST] = (struct nlattr *) &dst_attr,
 586                [RTA_PREFSRC] = (struct nlattr * ) &prefsrc_attr,
 587                [RTA_OIF] = (struct nlattr *) &oif_attr,
 588        };
 589
 590        memset(&req.rtm, 0, sizeof(req.rtm));
 591
 592        if (type == RTN_UNICAST)
 593                tb = dn_fib_get_table(RT_MIN_TABLE, 1);
 594        else
 595                tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
 596
 597        if (tb == NULL)
 598                return;
 599
 600        req.nlh.nlmsg_len = sizeof(req);
 601        req.nlh.nlmsg_type = cmd;
 602        req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
 603        req.nlh.nlmsg_pid = 0;
 604        req.nlh.nlmsg_seq = 0;
 605
 606        req.rtm.rtm_dst_len = dst_len;
 607        req.rtm.rtm_table = tb->n;
 608        req.rtm.rtm_protocol = RTPROT_KERNEL;
 609        req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
 610        req.rtm.rtm_type = type;
 611
 612        if (cmd == RTM_NEWROUTE)
 613                tb->insert(tb, &req.rtm, attrs, &req.nlh, NULL);
 614        else
 615                tb->delete(tb, &req.rtm, attrs, &req.nlh, NULL);
 616}
 617
 618static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
 619{
 620
 621        fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
 622
 623#if 0
 624        if (!(dev->flags&IFF_UP))
 625                return;
 626        /* In the future, we will want to add default routes here */
 627
 628#endif
 629}
 630
 631static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
 632{
 633        int found_it = 0;
 634        struct net_device *dev;
 635        struct dn_dev *dn_db;
 636        struct dn_ifaddr *ifa2;
 637
 638        ASSERT_RTNL();
 639
 640        /* Scan device list */
 641        rcu_read_lock();
 642        for_each_netdev_rcu(&init_net, dev) {
 643                dn_db = rcu_dereference(dev->dn_ptr);
 644                if (dn_db == NULL)
 645                        continue;
 646                for (ifa2 = rcu_dereference(dn_db->ifa_list);
 647                     ifa2 != NULL;
 648                     ifa2 = rcu_dereference(ifa2->ifa_next)) {
 649                        if (ifa2->ifa_local == ifa->ifa_local) {
 650                                found_it = 1;
 651                                break;
 652                        }
 653                }
 654        }
 655        rcu_read_unlock();
 656
 657        if (found_it == 0) {
 658                fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
 659
 660                if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
 661                        if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
 662                                dn_fib_flush();
 663                }
 664        }
 665}
 666
 667static void dn_fib_disable_addr(struct net_device *dev, int force)
 668{
 669        if (dn_fib_sync_down(0, dev, force))
 670                dn_fib_flush();
 671        dn_rt_cache_flush(0);
 672        neigh_ifdown(&dn_neigh_table, dev);
 673}
 674
 675static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
 676{
 677        struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
 678
 679        switch (event) {
 680        case NETDEV_UP:
 681                dn_fib_add_ifaddr(ifa);
 682                dn_fib_sync_up(ifa->ifa_dev->dev);
 683                dn_rt_cache_flush(-1);
 684                break;
 685        case NETDEV_DOWN:
 686                dn_fib_del_ifaddr(ifa);
 687                if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
 688                        dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
 689                } else {
 690                        dn_rt_cache_flush(-1);
 691                }
 692                break;
 693        }
 694        return NOTIFY_DONE;
 695}
 696
 697static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
 698{
 699        int ret = 0;
 700        int scope = RT_SCOPE_NOWHERE;
 701
 702        if (force)
 703                scope = -1;
 704
 705        for_fib_info() {
 706                /*
 707                 * This makes no sense for DECnet.... we will almost
 708                 * certainly have more than one local address the same
 709                 * over all our interfaces. It needs thinking about
 710                 * some more.
 711                 */
 712                if (local && fi->fib_prefsrc == local) {
 713                        fi->fib_flags |= RTNH_F_DEAD;
 714                        ret++;
 715                } else if (dev && fi->fib_nhs) {
 716                        int dead = 0;
 717
 718                        change_nexthops(fi) {
 719                                if (nh->nh_flags&RTNH_F_DEAD)
 720                                        dead++;
 721                                else if (nh->nh_dev == dev &&
 722                                                nh->nh_scope != scope) {
 723                                        spin_lock_bh(&dn_fib_multipath_lock);
 724                                        nh->nh_flags |= RTNH_F_DEAD;
 725                                        fi->fib_power -= nh->nh_power;
 726                                        nh->nh_power = 0;
 727                                        spin_unlock_bh(&dn_fib_multipath_lock);
 728                                        dead++;
 729                                }
 730                        } endfor_nexthops(fi)
 731                        if (dead == fi->fib_nhs) {
 732                                fi->fib_flags |= RTNH_F_DEAD;
 733                                ret++;
 734                        }
 735                }
 736        } endfor_fib_info();
 737        return ret;
 738}
 739
 740
 741static int dn_fib_sync_up(struct net_device *dev)
 742{
 743        int ret = 0;
 744
 745        if (!(dev->flags&IFF_UP))
 746                return 0;
 747
 748        for_fib_info() {
 749                int alive = 0;
 750
 751                change_nexthops(fi) {
 752                        if (!(nh->nh_flags&RTNH_F_DEAD)) {
 753                                alive++;
 754                                continue;
 755                        }
 756                        if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
 757                                continue;
 758                        if (nh->nh_dev != dev || dev->dn_ptr == NULL)
 759                                continue;
 760                        alive++;
 761                        spin_lock_bh(&dn_fib_multipath_lock);
 762                        nh->nh_power = 0;
 763                        nh->nh_flags &= ~RTNH_F_DEAD;
 764                        spin_unlock_bh(&dn_fib_multipath_lock);
 765                } endfor_nexthops(fi);
 766
 767                if (alive > 0) {
 768                        fi->fib_flags &= ~RTNH_F_DEAD;
 769                        ret++;
 770                }
 771        } endfor_fib_info();
 772        return ret;
 773}
 774
 775static struct notifier_block dn_fib_dnaddr_notifier = {
 776        .notifier_call = dn_fib_dnaddr_event,
 777};
 778
 779void __exit dn_fib_cleanup(void)
 780{
 781        dn_fib_table_cleanup();
 782        dn_fib_rules_cleanup();
 783
 784        unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
 785}
 786
 787
 788void __init dn_fib_init(void)
 789{
 790        dn_fib_table_init();
 791        dn_fib_rules_init();
 792
 793        register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
 794
 795        rtnl_register_module(THIS_MODULE, PF_DECnet, RTM_NEWROUTE,
 796                             dn_fib_rtm_newroute, NULL, 0);
 797        rtnl_register_module(THIS_MODULE, PF_DECnet, RTM_DELROUTE,
 798                             dn_fib_rtm_delroute, NULL, 0);
 799}
 800