linux/net/decnet/dn_fib.c
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   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 <asm/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
  59static DEFINE_SPINLOCK(dn_fib_multipath_lock);
  60static struct dn_fib_info *dn_fib_info_list;
  61static DEFINE_SPINLOCK(dn_fib_info_lock);
  62
  63static 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
  82static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
  83static int dn_fib_sync_up(struct net_device *dev);
  84
  85void 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
 100void 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
 116static 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
 132static 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
 159static 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
 175static 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
 199static 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;
 248out:
 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
 271struct 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 flavour = attr->rta_type;
 306                        if (flavour) {
 307                                if (flavour > RTAX_MAX)
 308                                        goto err_inval;
 309                                fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
 310                        }
 311                        attr = RTA_NEXT(attr, attrlen);
 312                }
 313        }
 314        if (rta->rta_prefsrc)
 315                memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
 316
 317        if (rta->rta_mp) {
 318                if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
 319                        goto failure;
 320                if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
 321                        goto err_inval;
 322                if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
 323                        goto err_inval;
 324        } else {
 325                struct dn_fib_nh *nh = fi->fib_nh;
 326                if (rta->rta_oif)
 327                        nh->nh_oif = *rta->rta_oif;
 328                if (rta->rta_gw)
 329                        memcpy(&nh->nh_gw, rta->rta_gw, 2);
 330                nh->nh_flags = r->rtm_flags;
 331                nh->nh_weight = 1;
 332        }
 333
 334        if (r->rtm_type == RTN_NAT) {
 335                if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
 336                        goto err_inval;
 337                memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
 338                goto link_it;
 339        }
 340
 341        if (dn_fib_props[r->rtm_type].error) {
 342                if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
 343                        goto err_inval;
 344                goto link_it;
 345        }
 346
 347        if (r->rtm_scope > RT_SCOPE_HOST)
 348                goto err_inval;
 349
 350        if (r->rtm_scope == RT_SCOPE_HOST) {
 351                struct dn_fib_nh *nh = fi->fib_nh;
 352
 353                /* Local address is added */
 354                if (nhs != 1 || nh->nh_gw)
 355                        goto err_inval;
 356                nh->nh_scope = RT_SCOPE_NOWHERE;
 357                nh->nh_dev = dev_get_by_index(&init_net, fi->fib_nh->nh_oif);
 358                err = -ENODEV;
 359                if (nh->nh_dev == NULL)
 360                        goto failure;
 361        } else {
 362                change_nexthops(fi) {
 363                        if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
 364                                goto failure;
 365                } endfor_nexthops(fi)
 366        }
 367
 368        if (fi->fib_prefsrc) {
 369                if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
 370                    memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
 371                        if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
 372                                goto err_inval;
 373        }
 374
 375link_it:
 376        if ((ofi = dn_fib_find_info(fi)) != NULL) {
 377                fi->fib_dead = 1;
 378                dn_fib_free_info(fi);
 379                ofi->fib_treeref++;
 380                return ofi;
 381        }
 382
 383        fi->fib_treeref++;
 384        atomic_inc(&fi->fib_clntref);
 385        spin_lock(&dn_fib_info_lock);
 386        fi->fib_next = dn_fib_info_list;
 387        fi->fib_prev = NULL;
 388        if (dn_fib_info_list)
 389                dn_fib_info_list->fib_prev = fi;
 390        dn_fib_info_list = fi;
 391        spin_unlock(&dn_fib_info_lock);
 392        return fi;
 393
 394err_inval:
 395        err = -EINVAL;
 396
 397failure:
 398        *errp = err;
 399        if (fi) {
 400                fi->fib_dead = 1;
 401                dn_fib_free_info(fi);
 402        }
 403
 404        return NULL;
 405}
 406
 407int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn *fld, struct dn_fib_res *res)
 408{
 409        int err = dn_fib_props[type].error;
 410
 411        if (err == 0) {
 412                if (fi->fib_flags & RTNH_F_DEAD)
 413                        return 1;
 414
 415                res->fi = fi;
 416
 417                switch(type) {
 418                        case RTN_NAT:
 419                                DN_FIB_RES_RESET(*res);
 420                                atomic_inc(&fi->fib_clntref);
 421                                return 0;
 422                        case RTN_UNICAST:
 423                        case RTN_LOCAL:
 424                                for_nexthops(fi) {
 425                                        if (nh->nh_flags & RTNH_F_DEAD)
 426                                                continue;
 427                                        if (!fld->flowidn_oif ||
 428                                            fld->flowidn_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
 449void dn_fib_select_multipath(const struct flowidn *fld, 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
 489static 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
 507static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 508{
 509        struct net *net = sock_net(skb->sk);
 510        struct dn_fib_table *tb;
 511        struct rtattr **rta = arg;
 512        struct rtmsg *r = NLMSG_DATA(nlh);
 513
 514        if (!net_eq(net, &init_net))
 515                return -EINVAL;
 516
 517        if (dn_fib_check_attr(r, rta))
 518                return -EINVAL;
 519
 520        tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
 521        if (tb)
 522                return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
 523
 524        return -ESRCH;
 525}
 526
 527static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 528{
 529        struct net *net = sock_net(skb->sk);
 530        struct dn_fib_table *tb;
 531        struct rtattr **rta = arg;
 532        struct rtmsg *r = NLMSG_DATA(nlh);
 533
 534        if (!net_eq(net, &init_net))
 535                return -EINVAL;
 536
 537        if (dn_fib_check_attr(r, rta))
 538                return -EINVAL;
 539
 540        tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
 541        if (tb)
 542                return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
 543
 544        return -ENOBUFS;
 545}
 546
 547static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
 548{
 549        struct dn_fib_table *tb;
 550        struct {
 551                struct nlmsghdr nlh;
 552                struct rtmsg rtm;
 553        } req;
 554        struct dn_kern_rta rta;
 555
 556        memset(&req.rtm, 0, sizeof(req.rtm));
 557        memset(&rta, 0, sizeof(rta));
 558
 559        if (type == RTN_UNICAST)
 560                tb = dn_fib_get_table(RT_MIN_TABLE, 1);
 561        else
 562                tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
 563
 564        if (tb == NULL)
 565                return;
 566
 567        req.nlh.nlmsg_len = sizeof(req);
 568        req.nlh.nlmsg_type = cmd;
 569        req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
 570        req.nlh.nlmsg_pid = 0;
 571        req.nlh.nlmsg_seq = 0;
 572
 573        req.rtm.rtm_dst_len = dst_len;
 574        req.rtm.rtm_table = tb->n;
 575        req.rtm.rtm_protocol = RTPROT_KERNEL;
 576        req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
 577        req.rtm.rtm_type = type;
 578
 579        rta.rta_dst = &dst;
 580        rta.rta_prefsrc = &ifa->ifa_local;
 581        rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
 582
 583        if (cmd == RTM_NEWROUTE)
 584                tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
 585        else
 586                tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
 587}
 588
 589static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
 590{
 591
 592        fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
 593
 594#if 0
 595        if (!(dev->flags&IFF_UP))
 596                return;
 597        /* In the future, we will want to add default routes here */
 598
 599#endif
 600}
 601
 602static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
 603{
 604        int found_it = 0;
 605        struct net_device *dev;
 606        struct dn_dev *dn_db;
 607        struct dn_ifaddr *ifa2;
 608
 609        ASSERT_RTNL();
 610
 611        /* Scan device list */
 612        rcu_read_lock();
 613        for_each_netdev_rcu(&init_net, dev) {
 614                dn_db = rcu_dereference(dev->dn_ptr);
 615                if (dn_db == NULL)
 616                        continue;
 617                for (ifa2 = rcu_dereference(dn_db->ifa_list);
 618                     ifa2 != NULL;
 619                     ifa2 = rcu_dereference(ifa2->ifa_next)) {
 620                        if (ifa2->ifa_local == ifa->ifa_local) {
 621                                found_it = 1;
 622                                break;
 623                        }
 624                }
 625        }
 626        rcu_read_unlock();
 627
 628        if (found_it == 0) {
 629                fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
 630
 631                if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
 632                        if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
 633                                dn_fib_flush();
 634                }
 635        }
 636}
 637
 638static void dn_fib_disable_addr(struct net_device *dev, int force)
 639{
 640        if (dn_fib_sync_down(0, dev, force))
 641                dn_fib_flush();
 642        dn_rt_cache_flush(0);
 643        neigh_ifdown(&dn_neigh_table, dev);
 644}
 645
 646static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
 647{
 648        struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
 649
 650        switch(event) {
 651                case NETDEV_UP:
 652                        dn_fib_add_ifaddr(ifa);
 653                        dn_fib_sync_up(ifa->ifa_dev->dev);
 654                        dn_rt_cache_flush(-1);
 655                        break;
 656                case NETDEV_DOWN:
 657                        dn_fib_del_ifaddr(ifa);
 658                        if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
 659                                dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
 660                        } else {
 661                                dn_rt_cache_flush(-1);
 662                        }
 663                        break;
 664        }
 665        return NOTIFY_DONE;
 666}
 667
 668static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
 669{
 670        int ret = 0;
 671        int scope = RT_SCOPE_NOWHERE;
 672
 673        if (force)
 674                scope = -1;
 675
 676        for_fib_info() {
 677                /*
 678                 * This makes no sense for DECnet.... we will almost
 679                 * certainly have more than one local address the same
 680                 * over all our interfaces. It needs thinking about
 681                 * some more.
 682                 */
 683                if (local && fi->fib_prefsrc == local) {
 684                        fi->fib_flags |= RTNH_F_DEAD;
 685                        ret++;
 686                } else if (dev && fi->fib_nhs) {
 687                        int dead = 0;
 688
 689                        change_nexthops(fi) {
 690                                if (nh->nh_flags&RTNH_F_DEAD)
 691                                        dead++;
 692                                else if (nh->nh_dev == dev &&
 693                                                nh->nh_scope != scope) {
 694                                        spin_lock_bh(&dn_fib_multipath_lock);
 695                                        nh->nh_flags |= RTNH_F_DEAD;
 696                                        fi->fib_power -= nh->nh_power;
 697                                        nh->nh_power = 0;
 698                                        spin_unlock_bh(&dn_fib_multipath_lock);
 699                                        dead++;
 700                                }
 701                        } endfor_nexthops(fi)
 702                        if (dead == fi->fib_nhs) {
 703                                fi->fib_flags |= RTNH_F_DEAD;
 704                                ret++;
 705                        }
 706                }
 707        } endfor_fib_info();
 708        return ret;
 709}
 710
 711
 712static int dn_fib_sync_up(struct net_device *dev)
 713{
 714        int ret = 0;
 715
 716        if (!(dev->flags&IFF_UP))
 717                return 0;
 718
 719        for_fib_info() {
 720                int alive = 0;
 721
 722                change_nexthops(fi) {
 723                        if (!(nh->nh_flags&RTNH_F_DEAD)) {
 724                                alive++;
 725                                continue;
 726                        }
 727                        if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
 728                                continue;
 729                        if (nh->nh_dev != dev || dev->dn_ptr == NULL)
 730                                continue;
 731                        alive++;
 732                        spin_lock_bh(&dn_fib_multipath_lock);
 733                        nh->nh_power = 0;
 734                        nh->nh_flags &= ~RTNH_F_DEAD;
 735                        spin_unlock_bh(&dn_fib_multipath_lock);
 736                } endfor_nexthops(fi);
 737
 738                if (alive > 0) {
 739                        fi->fib_flags &= ~RTNH_F_DEAD;
 740                        ret++;
 741                }
 742        } endfor_fib_info();
 743        return ret;
 744}
 745
 746static struct notifier_block dn_fib_dnaddr_notifier = {
 747        .notifier_call = dn_fib_dnaddr_event,
 748};
 749
 750void __exit dn_fib_cleanup(void)
 751{
 752        dn_fib_table_cleanup();
 753        dn_fib_rules_cleanup();
 754
 755        unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
 756}
 757
 758
 759void __init dn_fib_init(void)
 760{
 761        dn_fib_table_init();
 762        dn_fib_rules_init();
 763
 764        register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
 765
 766        rtnl_register(PF_DECnet, RTM_NEWROUTE, dn_fib_rtm_newroute, NULL);
 767        rtnl_register(PF_DECnet, RTM_DELROUTE, dn_fib_rtm_delroute, NULL);
 768}
 769
 770
 771