net/8021q/vlan_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/skbuff.h>
   3 #include <linux/netdevice.h>
   4 #include <linux/if_vlan.h>
   5 #include <linux/netpoll.h>
   6 #include <linux/export.h>
   7 #include <net/gro.h>
   8 #include "vlan.h"
   9
  10 bool vlan_do_receive(struct sk_buff **skbp)
  11 {
  12         struct sk_buff *skb = *skbp;
  13         __be16 vlan_proto = skb->vlan_proto;
  14         u16 vlan_id = skb_vlan_tag_get_id(skb);
  15         struct net_device *vlan_dev;
  16         struct vlan_pcpu_stats *rx_stats;
  17
  18         vlan_dev = vlan_find_dev(skb->dev, vlan_proto, vlan_id);
  19         if (!vlan_dev)
  20                 return false;
  21
  22         skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
  23         if (unlikely(!skb))
  24                 return false;
  25
  26         if (unlikely(!(vlan_dev->flags & IFF_UP))) {
  27                 kfree_skb(skb);
  28                 *skbp = NULL;
  29                 return false;
  30         }
  31
  32         skb->dev = vlan_dev;
  33         if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) {
  34                 /* Our lower layer thinks this is not local, let's make sure.
  35                  * This allows the VLAN to have a different MAC than the
  36                  * underlying device, and still route correctly. */
  37                 if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
  38                         skb->pkt_type = PACKET_HOST;
  39         }
  40
  41         if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR) &&
  42             !netif_is_macvlan_port(vlan_dev) &&
  43             !netif_is_bridge_port(vlan_dev)) {
  44                 unsigned int offset = skb->data - skb_mac_header(skb);
  45
  46                 /*
  47                  * vlan_insert_tag expect skb->data pointing to mac header.
  48                  * So change skb->data before calling it and change back to
  49                  * original position later
  50                  */
  51                 skb_push(skb, offset);
  52                 skb = *skbp = vlan_insert_inner_tag(skb, skb->vlan_proto,
  53                                                     skb->vlan_tci, skb->mac_len);
  54                 if (!skb)
  55                         return false;
  56                 skb_pull(skb, offset + VLAN_HLEN);
  57                 skb_reset_mac_len(skb);
  58         }
  59
  60         skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
  61         __vlan_hwaccel_clear_tag(skb);
  62
  63         rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
  64
  65         u64_stats_update_begin(&rx_stats->syncp);
  66         rx_stats->rx_packets++;
  67         rx_stats->rx_bytes += skb->len;
  68         if (skb->pkt_type == PACKET_MULTICAST)
  69                 rx_stats->rx_multicast++;
  70         u64_stats_update_end(&rx_stats->syncp);
  71
  72         return true;
  73 }
  74
  75 /* Must be invoked with rcu_read_lock. */
  76 struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
  77                                         __be16 vlan_proto, u16 vlan_id)
  78 {
  79         struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
  80
  81         if (vlan_info) {
  82                 return vlan_group_get_device(&vlan_info->grp,
  83                                              vlan_proto, vlan_id);
  84         } else {
  85                 /*
  86                  * Lower devices of master uppers (bonding, team) do not have
  87                  * grp assigned to themselves. Grp is assigned to upper device
  88                  * instead.
  89                  */
  90                 struct net_device *upper_dev;
  91
  92                 upper_dev = netdev_master_upper_dev_get_rcu(dev);
  93                 if (upper_dev)
  94                         return __vlan_find_dev_deep_rcu(upper_dev,
  95                                                     vlan_proto, vlan_id);
  96         }
  97
  98         return NULL;
  99 }
 100 EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
 101
 102 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
 103 {
 104         struct net_device *ret = vlan_dev_priv(dev)->real_dev;
 105
 106         while (is_vlan_dev(ret))
 107                 ret = vlan_dev_priv(ret)->real_dev;
 108
 109         return ret;
 110 }
 111 EXPORT_SYMBOL(vlan_dev_real_dev);
 112
 113 u16 vlan_dev_vlan_id(const struct net_device *dev)
 114 {
 115         return vlan_dev_priv(dev)->vlan_id;
 116 }
 117 EXPORT_SYMBOL(vlan_dev_vlan_id);
 118
 119 __be16 vlan_dev_vlan_proto(const struct net_device *dev)
 120 {
 121         return vlan_dev_priv(dev)->vlan_proto;
 122 }
 123 EXPORT_SYMBOL(vlan_dev_vlan_proto);
 124
 125 /*
 126  * vlan info and vid list
 127  */
 128
 129 static void vlan_group_free(struct vlan_group *grp)
 130 {
 131         int i, j;
 132
 133         for (i = 0; i < VLAN_PROTO_NUM; i++)
 134                 for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
 135                         kfree(grp->vlan_devices_arrays[i][j]);
 136 }
 137
 138 static void vlan_info_free(struct vlan_info *vlan_info)
 139 {
 140         vlan_group_free(&vlan_info->grp);
 141         kfree(vlan_info);
 142 }
 143
 144 static void vlan_info_rcu_free(struct rcu_head *rcu)
 145 {
 146         vlan_info_free(container_of(rcu, struct vlan_info, rcu));
 147 }
 148
 149 static struct vlan_info *vlan_info_alloc(struct net_device *dev)
 150 {
 151         struct vlan_info *vlan_info;
 152
 153         vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
 154         if (!vlan_info)
 155                 return NULL;
 156
 157         vlan_info->real_dev = dev;
 158         INIT_LIST_HEAD(&vlan_info->vid_list);
 159         return vlan_info;
 160 }
 161
 162 struct vlan_vid_info {
 163         struct list_head list;
 164         __be16 proto;
 165         u16 vid;
 166         int refcount;
 167 };
 168
 169 static bool vlan_hw_filter_capable(const struct net_device *dev, __be16 proto)
 170 {
 171         if (proto == htons(ETH_P_8021Q) &&
 172             dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
 173                 return true;
 174         if (proto == htons(ETH_P_8021AD) &&
 175             dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
 176                 return true;
 177         return false;
 178 }
 179
 180 static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
 181                                                __be16 proto, u16 vid)
 182 {
 183         struct vlan_vid_info *vid_info;
 184
 185         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
 186                 if (vid_info->proto == proto && vid_info->vid == vid)
 187                         return vid_info;
 188         }
 189         return NULL;
 190 }
 191
 192 static struct vlan_vid_info *vlan_vid_info_alloc(__be16 proto, u16 vid)
 193 {
 194         struct vlan_vid_info *vid_info;
 195
 196         vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
 197         if (!vid_info)
 198                 return NULL;
 199         vid_info->proto = proto;
 200         vid_info->vid = vid;
 201
 202         return vid_info;
 203 }
 204
 205 static int vlan_add_rx_filter_info(struct net_device *dev, __be16 proto, u16 vid)
 206 {
 207         if (!vlan_hw_filter_capable(dev, proto))
 208                 return 0;
 209
 210         if (netif_device_present(dev))
 211                 return dev->netdev_ops->ndo_vlan_rx_add_vid(dev, proto, vid);
 212         else
 213                 return -ENODEV;
 214 }
 215
 216 static int vlan_kill_rx_filter_info(struct net_device *dev, __be16 proto, u16 vid)
 217 {
 218         if (!vlan_hw_filter_capable(dev, proto))
 219                 return 0;
 220
 221         if (netif_device_present(dev))
 222                 return dev->netdev_ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
 223         else
 224                 return -ENODEV;
 225 }
 226
 227 int vlan_for_each(struct net_device *dev,
 228                   int (*action)(struct net_device *dev, int vid, void *arg),
 229                   void *arg)
 230 {
 231         struct vlan_vid_info *vid_info;
 232         struct vlan_info *vlan_info;
 233         struct net_device *vdev;
 234         int ret;
 235
 236         ASSERT_RTNL();
 237
 238         vlan_info = rtnl_dereference(dev->vlan_info);
 239         if (!vlan_info)
 240                 return 0;
 241
 242         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
 243                 vdev = vlan_group_get_device(&vlan_info->grp, vid_info->proto,
 244                                              vid_info->vid);
 245                 ret = action(vdev, vid_info->vid, arg);
 246                 if (ret)
 247                         return ret;
 248         }
 249
 250         return 0;
 251 }
 252 EXPORT_SYMBOL(vlan_for_each);
 253
 254 int vlan_filter_push_vids(struct vlan_info *vlan_info, __be16 proto)
 255 {
 256         struct net_device *real_dev = vlan_info->real_dev;
 257         struct vlan_vid_info *vlan_vid_info;
 258         int err;
 259
 260         list_for_each_entry(vlan_vid_info, &vlan_info->vid_list, list) {
 261                 if (vlan_vid_info->proto == proto) {
 262                         err = vlan_add_rx_filter_info(real_dev, proto,
 263                                                       vlan_vid_info->vid);
 264                         if (err)
 265                                 goto unwind;
 266                 }
 267         }
 268
 269         return 0;
 270
 271 unwind:
 272         list_for_each_entry_continue_reverse(vlan_vid_info,
 273                                              &vlan_info->vid_list, list) {
 274                 if (vlan_vid_info->proto == proto)
 275                         vlan_kill_rx_filter_info(real_dev, proto,
 276                                                  vlan_vid_info->vid);
 277         }
 278
 279         return err;
 280 }
 281 EXPORT_SYMBOL(vlan_filter_push_vids);
 282
 283 void vlan_filter_drop_vids(struct vlan_info *vlan_info, __be16 proto)
 284 {
 285         struct vlan_vid_info *vlan_vid_info;
 286
 287         list_for_each_entry(vlan_vid_info, &vlan_info->vid_list, list)
 288                 if (vlan_vid_info->proto == proto)
 289                         vlan_kill_rx_filter_info(vlan_info->real_dev,
 290                                                  vlan_vid_info->proto,
 291                                                  vlan_vid_info->vid);
 292 }
 293 EXPORT_SYMBOL(vlan_filter_drop_vids);
 294
 295 static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
 296                           struct vlan_vid_info **pvid_info)
 297 {
 298         struct net_device *dev = vlan_info->real_dev;
 299         struct vlan_vid_info *vid_info;
 300         int err;
 301
 302         vid_info = vlan_vid_info_alloc(proto, vid);
 303         if (!vid_info)
 304                 return -ENOMEM;
 305
 306         err = vlan_add_rx_filter_info(dev, proto, vid);
 307         if (err) {
 308                 kfree(vid_info);
 309                 return err;
 310         }
 311
 312         list_add(&vid_info->list, &vlan_info->vid_list);
 313         vlan_info->nr_vids++;
 314         *pvid_info = vid_info;
 315         return 0;
 316 }
 317
 318 int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
 319 {
 320         struct vlan_info *vlan_info;
 321         struct vlan_vid_info *vid_info;
 322         bool vlan_info_created = false;
 323         int err;
 324
 325         ASSERT_RTNL();
 326
 327         vlan_info = rtnl_dereference(dev->vlan_info);
 328         if (!vlan_info) {
 329                 vlan_info = vlan_info_alloc(dev);
 330                 if (!vlan_info)
 331                         return -ENOMEM;
 332                 vlan_info_created = true;
 333         }
 334         vid_info = vlan_vid_info_get(vlan_info, proto, vid);
 335         if (!vid_info) {
 336                 err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
 337                 if (err)
 338                         goto out_free_vlan_info;
 339         }
 340         vid_info->refcount++;
 341
 342         if (vlan_info_created)
 343                 rcu_assign_pointer(dev->vlan_info, vlan_info);
 344
 345         return 0;
 346
 347 out_free_vlan_info:
 348         if (vlan_info_created)
 349                 kfree(vlan_info);
 350         return err;
 351 }
 352 EXPORT_SYMBOL(vlan_vid_add);
 353
 354 static void __vlan_vid_del(struct vlan_info *vlan_info,
 355                            struct vlan_vid_info *vid_info)
 356 {
 357         struct net_device *dev = vlan_info->real_dev;
 358         __be16 proto = vid_info->proto;
 359         u16 vid = vid_info->vid;
 360         int err;
 361
 362         err = vlan_kill_rx_filter_info(dev, proto, vid);
 363         if (err && dev->reg_state != NETREG_UNREGISTERING)
 364                 netdev_warn(dev, "failed to kill vid %04x/%d\n", proto, vid);
 365
 366         list_del(&vid_info->list);
 367         kfree(vid_info);
 368         vlan_info->nr_vids--;
 369 }
 370
 371 void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
 372 {
 373         struct vlan_info *vlan_info;
 374         struct vlan_vid_info *vid_info;
 375
 376         ASSERT_RTNL();
 377
 378         vlan_info = rtnl_dereference(dev->vlan_info);
 379         if (!vlan_info)
 380                 return;
 381
 382         vid_info = vlan_vid_info_get(vlan_info, proto, vid);
 383         if (!vid_info)
 384                 return;
 385         vid_info->refcount--;
 386         if (vid_info->refcount == 0) {
 387                 __vlan_vid_del(vlan_info, vid_info);
 388                 if (vlan_info->nr_vids == 0) {
 389                         RCU_INIT_POINTER(dev->vlan_info, NULL);
 390                         call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
 391                 }
 392         }
 393 }
 394 EXPORT_SYMBOL(vlan_vid_del);
 395
 396 int vlan_vids_add_by_dev(struct net_device *dev,
 397                          const struct net_device *by_dev)
 398 {
 399         struct vlan_vid_info *vid_info;
 400         struct vlan_info *vlan_info;
 401         int err;
 402
 403         ASSERT_RTNL();
 404
 405         vlan_info = rtnl_dereference(by_dev->vlan_info);
 406         if (!vlan_info)
 407                 return 0;
 408
 409         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
 410                 err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
 411                 if (err)
 412                         goto unwind;
 413         }
 414         return 0;
 415
 416 unwind:
 417         list_for_each_entry_continue_reverse(vid_info,
 418                                              &vlan_info->vid_list,
 419                                              list) {
 420                 vlan_vid_del(dev, vid_info->proto, vid_info->vid);
 421         }
 422
 423         return err;
 424 }
 425 EXPORT_SYMBOL(vlan_vids_add_by_dev);
 426
 427 void vlan_vids_del_by_dev(struct net_device *dev,
 428                           const struct net_device *by_dev)
 429 {
 430         struct vlan_vid_info *vid_info;
 431         struct vlan_info *vlan_info;
 432
 433         ASSERT_RTNL();
 434
 435         vlan_info = rtnl_dereference(by_dev->vlan_info);
 436         if (!vlan_info)
 437                 return;
 438
 439         list_for_each_entry(vid_info, &vlan_info->vid_list, list)
 440                 vlan_vid_del(dev, vid_info->proto, vid_info->vid);
 441 }
 442 EXPORT_SYMBOL(vlan_vids_del_by_dev);
 443
 444 bool vlan_uses_dev(const struct net_device *dev)
 445 {
 446         struct vlan_info *vlan_info;
 447
 448         ASSERT_RTNL();
 449
 450         vlan_info = rtnl_dereference(dev->vlan_info);
 451         if (!vlan_info)
 452                 return false;
 453         return vlan_info->grp.nr_vlan_devs ? true : false;
 454 }
 455 EXPORT_SYMBOL(vlan_uses_dev);
 456
 457 static struct sk_buff *vlan_gro_receive(struct list_head *head,
 458                                         struct sk_buff *skb)
 459 {
 460         const struct packet_offload *ptype;
 461         unsigned int hlen, off_vlan;
 462         struct sk_buff *pp = NULL;
 463         struct vlan_hdr *vhdr;
 464         struct sk_buff *p;
 465         __be16 type;
 466         int flush = 1;
 467
 468         off_vlan = skb_gro_offset(skb);
 469         hlen = off_vlan + sizeof(*vhdr);
 470         vhdr = skb_gro_header_fast(skb, off_vlan);
 471         if (skb_gro_header_hard(skb, hlen)) {
 472                 vhdr = skb_gro_header_slow(skb, hlen, off_vlan);
 473                 if (unlikely(!vhdr))
 474                         goto out;
 475         }
 476
 477         type = vhdr->h_vlan_encapsulated_proto;
 478
 479         rcu_read_lock();
 480         ptype = gro_find_receive_by_type(type);
 481         if (!ptype)
 482                 goto out_unlock;
 483
 484         flush = 0;
 485
 486         list_for_each_entry(p, head, list) {
 487                 struct vlan_hdr *vhdr2;
 488
 489                 if (!NAPI_GRO_CB(p)->same_flow)
 490                         continue;
 491
 492                 vhdr2 = (struct vlan_hdr *)(p->data + off_vlan);
 493                 if (compare_vlan_header(vhdr, vhdr2))
 494                         NAPI_GRO_CB(p)->same_flow = 0;
 495         }
 496
 497         skb_gro_pull(skb, sizeof(*vhdr));
 498         skb_gro_postpull_rcsum(skb, vhdr, sizeof(*vhdr));
 499
 500         pp = indirect_call_gro_receive_inet(ptype->callbacks.gro_receive,
 501                                             ipv6_gro_receive, inet_gro_receive,
 502                                             head, skb);
 503
 504 out_unlock:
 505         rcu_read_unlock();
 506 out:
 507         skb_gro_flush_final(skb, pp, flush);
 508
 509         return pp;
 510 }
 511
 512 static int vlan_gro_complete(struct sk_buff *skb, int nhoff)
 513 {
 514         struct vlan_hdr *vhdr = (struct vlan_hdr *)(skb->data + nhoff);
 515         __be16 type = vhdr->h_vlan_encapsulated_proto;
 516         struct packet_offload *ptype;
 517         int err = -ENOENT;
 518
 519         rcu_read_lock();
 520         ptype = gro_find_complete_by_type(type);
 521         if (ptype)
 522                 err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete,
 523                                          ipv6_gro_complete, inet_gro_complete,
 524                                          skb, nhoff + sizeof(*vhdr));
 525
 526         rcu_read_unlock();
 527         return err;
 528 }
 529
 530 static struct packet_offload vlan_packet_offloads[] __read_mostly = {
 531         {
 532                 .type = cpu_to_be16(ETH_P_8021Q),
 533                 .priority = 10,
 534                 .callbacks = {
 535                         .gro_receive = vlan_gro_receive,
 536                         .gro_complete = vlan_gro_complete,
 537                 },
 538         },
 539         {
 540                 .type = cpu_to_be16(ETH_P_8021AD),
 541                 .priority = 10,
 542                 .callbacks = {
 543                         .gro_receive = vlan_gro_receive,
 544                         .gro_complete = vlan_gro_complete,
 545                 },
 546         },
 547 };
 548
 549 static int __init vlan_offload_init(void)
 550 {
 551         unsigned int i;
 552
 553         for (i = 0; i < ARRAY_SIZE(vlan_packet_offloads); i++)
 554                 dev_add_offload(&vlan_packet_offloads[i]);
 555
 556         return 0;
 557 }
 558
 559 fs_initcall(vlan_offload_init);