1 /* Linux multicast routing support 2 * Common logic shared by IPv4 [ipmr] and IPv6 [ip6mr] implementation 3 */ 4 5 #include <linux/rhashtable.h> 6 #include <linux/mroute_base.h> 7 8 /* Sets everything common except 'dev', since that is done under locking */ 9 void vif_device_init(struct vif_device *v, 10 struct net_device *dev, 11 unsigned long rate_limit, 12 unsigned char threshold, 13 unsigned short flags, 14 unsigned short get_iflink_mask) 15 { 16 RCU_INIT_POINTER(v->dev, NULL); 17 v->bytes_in = 0; 18 v->bytes_out = 0; 19 v->pkt_in = 0; 20 v->pkt_out = 0; 21 v->rate_limit = rate_limit; 22 v->flags = flags; 23 v->threshold = threshold; 24 if (v->flags & get_iflink_mask) 25 v->link = dev_get_iflink(dev); 26 else 27 v->link = dev->ifindex; 28 } 29 EXPORT_SYMBOL(vif_device_init); 30 31 struct mr_table * 32 mr_table_alloc(struct net *net, u32 id, 33 struct mr_table_ops *ops, 34 void (*expire_func)(struct timer_list *t), 35 void (*table_set)(struct mr_table *mrt, 36 struct net *net)) 37 { 38 struct mr_table *mrt; 39 int err; 40 41 mrt = kzalloc(sizeof(*mrt), GFP_KERNEL); 42 if (!mrt) 43 return ERR_PTR(-ENOMEM); 44 mrt->id = id; 45 write_pnet(&mrt->net, net); 46 47 mrt->ops = *ops; 48 err = rhltable_init(&mrt->mfc_hash, mrt->ops.rht_params); 49 if (err) { 50 kfree(mrt); 51 return ERR_PTR(err); 52 } 53 INIT_LIST_HEAD(&mrt->mfc_cache_list); 54 INIT_LIST_HEAD(&mrt->mfc_unres_queue); 55 56 timer_setup(&mrt->ipmr_expire_timer, expire_func, 0); 57 58 mrt->mroute_reg_vif_num = -1; 59 table_set(mrt, net); 60 return mrt; 61 } 62 EXPORT_SYMBOL(mr_table_alloc); 63 64 void *mr_mfc_find_parent(struct mr_table *mrt, void *hasharg, int parent) 65 { 66 struct rhlist_head *tmp, *list; 67 struct mr_mfc *c; 68 69 list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params); 70 rhl_for_each_entry_rcu(c, tmp, list, mnode) 71 if (parent == -1 || parent == c->mfc_parent) 72 return c; 73 74 return NULL; 75 } 76 EXPORT_SYMBOL(mr_mfc_find_parent); 77 78 void *mr_mfc_find_any_parent(struct mr_table *mrt, int vifi) 79 { 80 struct rhlist_head *tmp, *list; 81 struct mr_mfc *c; 82 83 list = rhltable_lookup(&mrt->mfc_hash, mrt->ops.cmparg_any, 84 *mrt->ops.rht_params); 85 rhl_for_each_entry_rcu(c, tmp, list, mnode) 86 if (c->mfc_un.res.ttls[vifi] < 255) 87 return c; 88 89 return NULL; 90 } 91 EXPORT_SYMBOL(mr_mfc_find_any_parent); 92 93 void *mr_mfc_find_any(struct mr_table *mrt, int vifi, void *hasharg) 94 { 95 struct rhlist_head *tmp, *list; 96 struct mr_mfc *c, *proxy; 97 98 list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params); 99 rhl_for_each_entry_rcu(c, tmp, list, mnode) { 100 if (c->mfc_un.res.ttls[vifi] < 255) 101 return c; 102 103 /* It's ok if the vifi is part of the static tree */ 104 proxy = mr_mfc_find_any_parent(mrt, c->mfc_parent); 105 if (proxy && proxy->mfc_un.res.ttls[vifi] < 255) 106 return c; 107 } 108 109 return mr_mfc_find_any_parent(mrt, vifi); 110 } 111 EXPORT_SYMBOL(mr_mfc_find_any); 112 113 #ifdef CONFIG_PROC_FS 114 void *mr_vif_seq_idx(struct net *net, struct mr_vif_iter *iter, loff_t pos) 115 { 116 struct mr_table *mrt = iter->mrt; 117 118 for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) { 119 if (!VIF_EXISTS(mrt, iter->ct)) 120 continue; 121 if (pos-- == 0) 122 return &mrt->vif_table[iter->ct]; 123 } 124 return NULL; 125 } 126 EXPORT_SYMBOL(mr_vif_seq_idx); 127 128 void *mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos) 129 { 130 struct mr_vif_iter *iter = seq->private; 131 struct net *net = seq_file_net(seq); 132 struct mr_table *mrt = iter->mrt; 133 134 ++*pos; 135 if (v == SEQ_START_TOKEN) 136 return mr_vif_seq_idx(net, iter, 0); 137 138 while (++iter->ct < mrt->maxvif) { 139 if (!VIF_EXISTS(mrt, iter->ct)) 140 continue; 141 return &mrt->vif_table[iter->ct]; 142 } 143 return NULL; 144 } 145 EXPORT_SYMBOL(mr_vif_seq_next); 146 147 void *mr_mfc_seq_idx(struct net *net, 148 struct mr_mfc_iter *it, loff_t pos) 149 { 150 struct mr_table *mrt = it->mrt; 151 struct mr_mfc *mfc; 152 153 rcu_read_lock(); 154 it->cache = &mrt->mfc_cache_list; 155 list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) 156 if (pos-- == 0) 157 return mfc; 158 rcu_read_unlock(); 159 160 spin_lock_bh(it->lock); 161 it->cache = &mrt->mfc_unres_queue; 162 list_for_each_entry(mfc, it->cache, list) 163 if (pos-- == 0) 164 return mfc; 165 spin_unlock_bh(it->lock); 166 167 it->cache = NULL; 168 return NULL; 169 } 170 EXPORT_SYMBOL(mr_mfc_seq_idx); 171 172 void *mr_mfc_seq_next(struct seq_file *seq, void *v, 173 loff_t *pos) 174 { 175 struct mr_mfc_iter *it = seq->private; 176 struct net *net = seq_file_net(seq); 177 struct mr_table *mrt = it->mrt; 178 struct mr_mfc *c = v; 179 180 ++*pos; 181 182 if (v == SEQ_START_TOKEN) 183 return mr_mfc_seq_idx(net, seq->private, 0); 184 185 if (c->list.next != it->cache) 186 return list_entry(c->list.next, struct mr_mfc, list); 187 188 if (it->cache == &mrt->mfc_unres_queue) 189 goto end_of_list; 190 191 /* exhausted cache_array, show unresolved */ 192 rcu_read_unlock(); 193 it->cache = &mrt->mfc_unres_queue; 194 195 spin_lock_bh(it->lock); 196 if (!list_empty(it->cache)) 197 return list_first_entry(it->cache, struct mr_mfc, list); 198 199 end_of_list: 200 spin_unlock_bh(it->lock); 201 it->cache = NULL; 202 203 return NULL; 204 } 205 EXPORT_SYMBOL(mr_mfc_seq_next); 206 #endif 207 208 int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb, 209 struct mr_mfc *c, struct rtmsg *rtm) 210 { 211 struct net_device *vif_dev; 212 struct rta_mfc_stats mfcs; 213 struct nlattr *mp_attr; 214 struct rtnexthop *nhp; 215 unsigned long lastuse; 216 int ct; 217 218 /* If cache is unresolved, don't try to parse IIF and OIF */ 219 if (c->mfc_parent >= MAXVIFS) { 220 rtm->rtm_flags |= RTNH_F_UNRESOLVED; 221 return -ENOENT; 222 } 223 224 rcu_read_lock(); 225 vif_dev = rcu_dereference(mrt->vif_table[c->mfc_parent].dev); 226 if (vif_dev && nla_put_u32(skb, RTA_IIF, vif_dev->ifindex) < 0) { 227 rcu_read_unlock(); 228 return -EMSGSIZE; 229 } 230 rcu_read_unlock(); 231 232 if (c->mfc_flags & MFC_OFFLOAD) 233 rtm->rtm_flags |= RTNH_F_OFFLOAD; 234 235 mp_attr = nla_nest_start_noflag(skb, RTA_MULTIPATH); 236 if (!mp_attr) 237 return -EMSGSIZE; 238 239 rcu_read_lock(); 240 for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) { 241 struct vif_device *vif = &mrt->vif_table[ct]; 242 243 vif_dev = rcu_dereference(vif->dev); 244 if (vif_dev && c->mfc_un.res.ttls[ct] < 255) { 245 246 nhp = nla_reserve_nohdr(skb, sizeof(*nhp)); 247 if (!nhp) { 248 rcu_read_unlock(); 249 nla_nest_cancel(skb, mp_attr); 250 return -EMSGSIZE; 251 } 252 253 nhp->rtnh_flags = 0; 254 nhp->rtnh_hops = c->mfc_un.res.ttls[ct]; 255 nhp->rtnh_ifindex = vif_dev->ifindex; 256 nhp->rtnh_len = sizeof(*nhp); 257 } 258 } 259 rcu_read_unlock(); 260 261 nla_nest_end(skb, mp_attr); 262 263 lastuse = READ_ONCE(c->mfc_un.res.lastuse); 264 lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0; 265 266 mfcs.mfcs_packets = c->mfc_un.res.pkt; 267 mfcs.mfcs_bytes = c->mfc_un.res.bytes; 268 mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if; 269 if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) || 270 nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse), 271 RTA_PAD)) 272 return -EMSGSIZE; 273 274 rtm->rtm_type = RTN_MULTICAST; 275 return 1; 276 } 277 EXPORT_SYMBOL(mr_fill_mroute); 278 279 static bool mr_mfc_uses_dev(const struct mr_table *mrt, 280 const struct mr_mfc *c, 281 const struct net_device *dev) 282 { 283 int ct; 284 285 for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) { 286 const struct net_device *vif_dev; 287 const struct vif_device *vif; 288 289 vif = &mrt->vif_table[ct]; 290 vif_dev = rcu_access_pointer(vif->dev); 291 if (vif_dev && c->mfc_un.res.ttls[ct] < 255 && 292 vif_dev == dev) 293 return true; 294 } 295 return false; 296 } 297 298 int mr_table_dump(struct mr_table *mrt, struct sk_buff *skb, 299 struct netlink_callback *cb, 300 int (*fill)(struct mr_table *mrt, struct sk_buff *skb, 301 u32 portid, u32 seq, struct mr_mfc *c, 302 int cmd, int flags), 303 spinlock_t *lock, struct fib_dump_filter *filter) 304 { 305 unsigned int e = 0, s_e = cb->args[1]; 306 unsigned int flags = NLM_F_MULTI; 307 struct mr_mfc *mfc; 308 int err; 309 310 if (filter->filter_set) 311 flags |= NLM_F_DUMP_FILTERED; 312 313 list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) { 314 if (e < s_e) 315 goto next_entry; 316 if (filter->dev && 317 !mr_mfc_uses_dev(mrt, mfc, filter->dev)) 318 goto next_entry; 319 320 err = fill(mrt, skb, NETLINK_CB(cb->skb).portid, 321 cb->nlh->nlmsg_seq, mfc, RTM_NEWROUTE, flags); 322 if (err < 0) 323 goto out; 324 next_entry: 325 e++; 326 } 327 328 spin_lock_bh(lock); 329 list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) { 330 if (e < s_e) 331 goto next_entry2; 332 if (filter->dev && 333 !mr_mfc_uses_dev(mrt, mfc, filter->dev)) 334 goto next_entry2; 335 336 err = fill(mrt, skb, NETLINK_CB(cb->skb).portid, 337 cb->nlh->nlmsg_seq, mfc, RTM_NEWROUTE, flags); 338 if (err < 0) { 339 spin_unlock_bh(lock); 340 goto out; 341 } 342 next_entry2: 343 e++; 344 } 345 spin_unlock_bh(lock); 346 err = 0; 347 out: 348 cb->args[1] = e; 349 return err; 350 } 351 EXPORT_SYMBOL(mr_table_dump); 352 353 int mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb, 354 struct mr_table *(*iter)(struct net *net, 355 struct mr_table *mrt), 356 int (*fill)(struct mr_table *mrt, 357 struct sk_buff *skb, 358 u32 portid, u32 seq, struct mr_mfc *c, 359 int cmd, int flags), 360 spinlock_t *lock, struct fib_dump_filter *filter) 361 { 362 unsigned int t = 0, s_t = cb->args[0]; 363 struct net *net = sock_net(skb->sk); 364 struct mr_table *mrt; 365 int err; 366 367 /* multicast does not track protocol or have route type other 368 * than RTN_MULTICAST 369 */ 370 if (filter->filter_set) { 371 if (filter->protocol || filter->flags || 372 (filter->rt_type && filter->rt_type != RTN_MULTICAST)) 373 return skb->len; 374 } 375 376 rcu_read_lock(); 377 for (mrt = iter(net, NULL); mrt; mrt = iter(net, mrt)) { 378 if (t < s_t) 379 goto next_table; 380 381 err = mr_table_dump(mrt, skb, cb, fill, lock, filter); 382 if (err < 0) 383 break; 384 cb->args[1] = 0; 385 next_table: 386 t++; 387 } 388 rcu_read_unlock(); 389 390 cb->args[0] = t; 391 392 return skb->len; 393 } 394 EXPORT_SYMBOL(mr_rtm_dumproute); 395 396 int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family, 397 int (*rules_dump)(struct net *net, 398 struct notifier_block *nb, 399 struct netlink_ext_ack *extack), 400 struct mr_table *(*mr_iter)(struct net *net, 401 struct mr_table *mrt), 402 struct netlink_ext_ack *extack) 403 { 404 struct mr_table *mrt; 405 int err; 406 407 err = rules_dump(net, nb, extack); 408 if (err) 409 return err; 410 411 for (mrt = mr_iter(net, NULL); mrt; mrt = mr_iter(net, mrt)) { 412 struct vif_device *v = &mrt->vif_table[0]; 413 struct net_device *vif_dev; 414 struct mr_mfc *mfc; 415 int vifi; 416 417 /* Notifiy on table VIF entries */ 418 rcu_read_lock(); 419 for (vifi = 0; vifi < mrt->maxvif; vifi++, v++) { 420 vif_dev = rcu_dereference(v->dev); 421 if (!vif_dev) 422 continue; 423 424 err = mr_call_vif_notifier(nb, family, 425 FIB_EVENT_VIF_ADD, v, 426 vif_dev, vifi, 427 mrt->id, extack); 428 if (err) 429 break; 430 } 431 rcu_read_unlock(); 432 433 if (err) 434 return err; 435 436 /* Notify on table MFC entries */ 437 list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) { 438 err = mr_call_mfc_notifier(nb, family, 439 FIB_EVENT_ENTRY_ADD, 440 mfc, mrt->id, extack); 441 if (err) 442 return err; 443 } 444 } 445 446 return 0; 447 } 448 EXPORT_SYMBOL(mr_dump); 449