net/ipv4/ipmr_base.c

   1 /* Linux multicast routing support
   2  * Common logic shared by IPv4 [ipmr] and IPv6 [ip6mr] implementation
   3  */
   4
   5 #include <linux/mroute_base.h>
   6
   7 /* Sets everything common except 'dev', since that is done under locking */
   8 void vif_device_init(struct vif_device *v,
   9                      struct net_device *dev,
  10                      unsigned long rate_limit,
  11                      unsigned char threshold,
  12                      unsigned short flags,
  13                      unsigned short get_iflink_mask)
  14 {
  15         v->dev = NULL;
  16         v->bytes_in = 0;
  17         v->bytes_out = 0;
  18         v->pkt_in = 0;
  19         v->pkt_out = 0;
  20         v->rate_limit = rate_limit;
  21         v->flags = flags;
  22         v->threshold = threshold;
  23         if (v->flags & get_iflink_mask)
  24                 v->link = dev_get_iflink(dev);
  25         else
  26                 v->link = dev->ifindex;
  27 }
  28 EXPORT_SYMBOL(vif_device_init);
  29
  30 struct mr_table *
  31 mr_table_alloc(struct net *net, u32 id,
  32                struct mr_table_ops *ops,
  33                void (*expire_func)(struct timer_list *t),
  34                void (*table_set)(struct mr_table *mrt,
  35                                  struct net *net))
  36 {
  37         struct mr_table *mrt;
  38         int err;
  39
  40         mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
  41         if (!mrt)
  42                 return ERR_PTR(-ENOMEM);
  43         mrt->id = id;
  44         write_pnet(&mrt->net, net);
  45
  46         mrt->ops = *ops;
  47         err = rhltable_init(&mrt->mfc_hash, mrt->ops.rht_params);
  48         if (err) {
  49                 kfree(mrt);
  50                 return ERR_PTR(err);
  51         }
  52         INIT_LIST_HEAD(&mrt->mfc_cache_list);
  53         INIT_LIST_HEAD(&mrt->mfc_unres_queue);
  54
  55         timer_setup(&mrt->ipmr_expire_timer, expire_func, 0);
  56
  57         mrt->mroute_reg_vif_num = -1;
  58         table_set(mrt, net);
  59         return mrt;
  60 }
  61 EXPORT_SYMBOL(mr_table_alloc);
  62
  63 void *mr_mfc_find_parent(struct mr_table *mrt, void *hasharg, int parent)
  64 {
  65         struct rhlist_head *tmp, *list;
  66         struct mr_mfc *c;
  67
  68         list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params);
  69         rhl_for_each_entry_rcu(c, tmp, list, mnode)
  70                 if (parent == -1 || parent == c->mfc_parent)
  71                         return c;
  72
  73         return NULL;
  74 }
  75 EXPORT_SYMBOL(mr_mfc_find_parent);
  76
  77 void *mr_mfc_find_any_parent(struct mr_table *mrt, int vifi)
  78 {
  79         struct rhlist_head *tmp, *list;
  80         struct mr_mfc *c;
  81
  82         list = rhltable_lookup(&mrt->mfc_hash, mrt->ops.cmparg_any,
  83                                *mrt->ops.rht_params);
  84         rhl_for_each_entry_rcu(c, tmp, list, mnode)
  85                 if (c->mfc_un.res.ttls[vifi] < 255)
  86                         return c;
  87
  88         return NULL;
  89 }
  90 EXPORT_SYMBOL(mr_mfc_find_any_parent);
  91
  92 void *mr_mfc_find_any(struct mr_table *mrt, int vifi, void *hasharg)
  93 {
  94         struct rhlist_head *tmp, *list;
  95         struct mr_mfc *c, *proxy;
  96
  97         list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params);
  98         rhl_for_each_entry_rcu(c, tmp, list, mnode) {
  99                 if (c->mfc_un.res.ttls[vifi] < 255)
 100                         return c;
 101
 102                 /* It's ok if the vifi is part of the static tree */
 103                 proxy = mr_mfc_find_any_parent(mrt, c->mfc_parent);
 104                 if (proxy && proxy->mfc_un.res.ttls[vifi] < 255)
 105                         return c;
 106         }
 107
 108         return mr_mfc_find_any_parent(mrt, vifi);
 109 }
 110 EXPORT_SYMBOL(mr_mfc_find_any);
 111
 112 #ifdef CONFIG_PROC_FS
 113 void *mr_vif_seq_idx(struct net *net, struct mr_vif_iter *iter, loff_t pos)
 114 {
 115         struct mr_table *mrt = iter->mrt;
 116
 117         for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
 118                 if (!VIF_EXISTS(mrt, iter->ct))
 119                         continue;
 120                 if (pos-- == 0)
 121                         return &mrt->vif_table[iter->ct];
 122         }
 123         return NULL;
 124 }
 125 EXPORT_SYMBOL(mr_vif_seq_idx);
 126
 127 void *mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 128 {
 129         struct mr_vif_iter *iter = seq->private;
 130         struct net *net = seq_file_net(seq);
 131         struct mr_table *mrt = iter->mrt;
 132
 133         ++*pos;
 134         if (v == SEQ_START_TOKEN)
 135                 return mr_vif_seq_idx(net, iter, 0);
 136
 137         while (++iter->ct < mrt->maxvif) {
 138                 if (!VIF_EXISTS(mrt, iter->ct))
 139                         continue;
 140                 return &mrt->vif_table[iter->ct];
 141         }
 142         return NULL;
 143 }
 144 EXPORT_SYMBOL(mr_vif_seq_next);
 145
 146 void *mr_mfc_seq_idx(struct net *net,
 147                      struct mr_mfc_iter *it, loff_t pos)
 148 {
 149         struct mr_table *mrt = it->mrt;
 150         struct mr_mfc *mfc;
 151
 152         rcu_read_lock();
 153         it->cache = &mrt->mfc_cache_list;
 154         list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
 155                 if (pos-- == 0)
 156                         return mfc;
 157         rcu_read_unlock();
 158
 159         spin_lock_bh(it->lock);
 160         it->cache = &mrt->mfc_unres_queue;
 161         list_for_each_entry(mfc, it->cache, list)
 162                 if (pos-- == 0)
 163                         return mfc;
 164         spin_unlock_bh(it->lock);
 165
 166         it->cache = NULL;
 167         return NULL;
 168 }
 169 EXPORT_SYMBOL(mr_mfc_seq_idx);
 170
 171 void *mr_mfc_seq_next(struct seq_file *seq, void *v,
 172                       loff_t *pos)
 173 {
 174         struct mr_mfc_iter *it = seq->private;
 175         struct net *net = seq_file_net(seq);
 176         struct mr_table *mrt = it->mrt;
 177         struct mr_mfc *c = v;
 178
 179         ++*pos;
 180
 181         if (v == SEQ_START_TOKEN)
 182                 return mr_mfc_seq_idx(net, seq->private, 0);
 183
 184         if (c->list.next != it->cache)
 185                 return list_entry(c->list.next, struct mr_mfc, list);
 186
 187         if (it->cache == &mrt->mfc_unres_queue)
 188                 goto end_of_list;
 189
 190         /* exhausted cache_array, show unresolved */
 191         rcu_read_unlock();
 192         it->cache = &mrt->mfc_unres_queue;
 193
 194         spin_lock_bh(it->lock);
 195         if (!list_empty(it->cache))
 196                 return list_first_entry(it->cache, struct mr_mfc, list);
 197
 198 end_of_list:
 199         spin_unlock_bh(it->lock);
 200         it->cache = NULL;
 201
 202         return NULL;
 203 }
 204 EXPORT_SYMBOL(mr_mfc_seq_next);
 205 #endif
 206
 207 int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 208                    struct mr_mfc *c, struct rtmsg *rtm)
 209 {
 210         struct rta_mfc_stats mfcs;
 211         struct nlattr *mp_attr;
 212         struct rtnexthop *nhp;
 213         unsigned long lastuse;
 214         int ct;
 215
 216         /* If cache is unresolved, don't try to parse IIF and OIF */
 217         if (c->mfc_parent >= MAXVIFS) {
 218                 rtm->rtm_flags |= RTNH_F_UNRESOLVED;
 219                 return -ENOENT;
 220         }
 221
 222         if (VIF_EXISTS(mrt, c->mfc_parent) &&
 223             nla_put_u32(skb, RTA_IIF,
 224                         mrt->vif_table[c->mfc_parent].dev->ifindex) < 0)
 225                 return -EMSGSIZE;
 226
 227         if (c->mfc_flags & MFC_OFFLOAD)
 228                 rtm->rtm_flags |= RTNH_F_OFFLOAD;
 229
 230         mp_attr = nla_nest_start(skb, RTA_MULTIPATH);
 231         if (!mp_attr)
 232                 return -EMSGSIZE;
 233
 234         for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
 235                 if (VIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
 236                         struct vif_device *vif;
 237
 238                         nhp = nla_reserve_nohdr(skb, sizeof(*nhp));
 239                         if (!nhp) {
 240                                 nla_nest_cancel(skb, mp_attr);
 241                                 return -EMSGSIZE;
 242                         }
 243
 244                         nhp->rtnh_flags = 0;
 245                         nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
 246                         vif = &mrt->vif_table[ct];
 247                         nhp->rtnh_ifindex = vif->dev->ifindex;
 248                         nhp->rtnh_len = sizeof(*nhp);
 249                 }
 250         }
 251
 252         nla_nest_end(skb, mp_attr);
 253
 254         lastuse = READ_ONCE(c->mfc_un.res.lastuse);
 255         lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
 256
 257         mfcs.mfcs_packets = c->mfc_un.res.pkt;
 258         mfcs.mfcs_bytes = c->mfc_un.res.bytes;
 259         mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
 260         if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) ||
 261             nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
 262                               RTA_PAD))
 263                 return -EMSGSIZE;
 264
 265         rtm->rtm_type = RTN_MULTICAST;
 266         return 1;
 267 }
 268 EXPORT_SYMBOL(mr_fill_mroute);
 269
 270 int mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb,
 271                      struct mr_table *(*iter)(struct net *net,
 272                                               struct mr_table *mrt),
 273                      int (*fill)(struct mr_table *mrt,
 274                                  struct sk_buff *skb,
 275                                  u32 portid, u32 seq, struct mr_mfc *c,
 276                                  int cmd, int flags),
 277                      spinlock_t *lock)
 278 {
 279         unsigned int t = 0, e = 0, s_t = cb->args[0], s_e = cb->args[1];
 280         struct net *net = sock_net(skb->sk);
 281         struct mr_table *mrt;
 282         struct mr_mfc *mfc;
 283
 284         rcu_read_lock();
 285         for (mrt = iter(net, NULL); mrt; mrt = iter(net, mrt)) {
 286                 if (t < s_t)
 287                         goto next_table;
 288                 list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) {
 289                         if (e < s_e)
 290                                 goto next_entry;
 291                         if (fill(mrt, skb, NETLINK_CB(cb->skb).portid,
 292                                  cb->nlh->nlmsg_seq, mfc,
 293                                  RTM_NEWROUTE, NLM_F_MULTI) < 0)
 294                                 goto done;
 295 next_entry:
 296                         e++;
 297                 }
 298                 e = 0;
 299                 s_e = 0;
 300
 301                 spin_lock_bh(lock);
 302                 list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
 303                         if (e < s_e)
 304                                 goto next_entry2;
 305                         if (fill(mrt, skb, NETLINK_CB(cb->skb).portid,
 306                                  cb->nlh->nlmsg_seq, mfc,
 307                                  RTM_NEWROUTE, NLM_F_MULTI) < 0) {
 308                                 spin_unlock_bh(lock);
 309                                 goto done;
 310                         }
 311 next_entry2:
 312                         e++;
 313                 }
 314                 spin_unlock_bh(lock);
 315                 e = 0;
 316                 s_e = 0;
 317 next_table:
 318                 t++;
 319         }
 320 done:
 321         rcu_read_unlock();
 322
 323         cb->args[1] = e;
 324         cb->args[0] = t;
 325
 326         return skb->len;
 327 }
 328 EXPORT_SYMBOL(mr_rtm_dumproute);
 329
 330 int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family,
 331             int (*rules_dump)(struct net *net,
 332                               struct notifier_block *nb),
 333             struct mr_table *(*mr_iter)(struct net *net,
 334                                         struct mr_table *mrt),
 335             rwlock_t *mrt_lock)
 336 {
 337         struct mr_table *mrt;
 338         int err;
 339
 340         err = rules_dump(net, nb);
 341         if (err)
 342                 return err;
 343
 344         for (mrt = mr_iter(net, NULL); mrt; mrt = mr_iter(net, mrt)) {
 345                 struct vif_device *v = &mrt->vif_table[0];
 346                 struct mr_mfc *mfc;
 347                 int vifi;
 348
 349                 /* Notifiy on table VIF entries */
 350                 read_lock(mrt_lock);
 351                 for (vifi = 0; vifi < mrt->maxvif; vifi++, v++) {
 352                         if (!v->dev)
 353                                 continue;
 354
 355                         mr_call_vif_notifier(nb, net, family,
 356                                              FIB_EVENT_VIF_ADD,
 357                                              v, vifi, mrt->id);
 358                 }
 359                 read_unlock(mrt_lock);
 360
 361                 /* Notify on table MFC entries */
 362                 list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
 363                         mr_call_mfc_notifier(nb, net, family,
 364                                              FIB_EVENT_ENTRY_ADD,
 365                                              mfc, mrt->id);
 366         }
 367
 368         return 0;
 369 }
 370 EXPORT_SYMBOL(mr_dump);