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 "vlan.h"
   8
   9 bool vlan_do_receive(struct sk_buff **skbp)
  10 {
  11         struct sk_buff *skb = *skbp;
  12         __be16 vlan_proto = skb->vlan_proto;
  13         u16 vlan_id = skb_vlan_tag_get_id(skb);
  14         struct net_device *vlan_dev;
  15         struct vlan_pcpu_stats *rx_stats;
  16
  17         vlan_dev = vlan_find_dev(skb->dev, vlan_proto, vlan_id);
  18         if (!vlan_dev)
  19                 return false;
  20
  21         skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
  22         if (unlikely(!skb))
  23                 return false;
  24
  25         if (unlikely(!(vlan_dev->flags & IFF_UP))) {
  26                 kfree_skb(skb);
  27                 *skbp = NULL;
  28                 return false;
  29         }
  30
  31         skb->dev = vlan_dev;
  32         if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) {
  33                 /* Our lower layer thinks this is not local, let's make sure.
  34                  * This allows the VLAN to have a different MAC than the
  35                  * underlying device, and still route correctly. */
  36                 if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
  37                         skb->pkt_type = PACKET_HOST;
  38         }
  39
  40         if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR) &&
  41             !netif_is_macvlan_port(vlan_dev) &&
  42             !netif_is_bridge_port(vlan_dev)) {
  43                 unsigned int offset = skb->data - skb_mac_header(skb);
  44
  45                 /*
  46                  * vlan_insert_tag expect skb->data pointing to mac header.
  47                  * So change skb->data before calling it and change back to
  48                  * original position later
  49                  */
  50                 skb_push(skb, offset);
  51                 skb = *skbp = vlan_insert_inner_tag(skb, skb->vlan_proto,
  52                                                     skb->vlan_tci, skb->mac_len);
  53                 if (!skb)
  54                         return false;
  55                 skb_pull(skb, offset + VLAN_HLEN);
  56                 skb_reset_mac_len(skb);
  57         }
  58
  59         skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
  60         skb->vlan_tci = 0;
  61
  62         rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
  63
  64         u64_stats_update_begin(&rx_stats->syncp);
  65         rx_stats->rx_packets++;
  66         rx_stats->rx_bytes += skb->len;
  67         if (skb->pkt_type == PACKET_MULTICAST)
  68                 rx_stats->rx_multicast++;
  69         u64_stats_update_end(&rx_stats->syncp);
  70
  71         return true;
  72 }
  73
  74 /* Must be invoked with rcu_read_lock. */
  75 struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
  76                                         __be16 vlan_proto, u16 vlan_id)
  77 {
  78         struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
  79
  80         if (vlan_info) {
  81                 return vlan_group_get_device(&vlan_info->grp,
  82                                              vlan_proto, vlan_id);
  83         } else {
  84                 /*
  85                  * Lower devices of master uppers (bonding, team) do not have
  86                  * grp assigned to themselves. Grp is assigned to upper device
  87                  * instead.
  88                  */
  89                 struct net_device *upper_dev;
  90
  91                 upper_dev = netdev_master_upper_dev_get_rcu(dev);
  92                 if (upper_dev)
  93                         return __vlan_find_dev_deep_rcu(upper_dev,
  94                                                     vlan_proto, vlan_id);
  95         }
  96
  97         return NULL;
  98 }
  99 EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
 100
 101 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
 102 {
 103         struct net_device *ret = vlan_dev_priv(dev)->real_dev;
 104
 105         while (is_vlan_dev(ret))
 106                 ret = vlan_dev_priv(ret)->real_dev;
 107
 108         return ret;
 109 }
 110 EXPORT_SYMBOL(vlan_dev_real_dev);
 111
 112 u16 vlan_dev_vlan_id(const struct net_device *dev)
 113 {
 114         return vlan_dev_priv(dev)->vlan_id;
 115 }
 116 EXPORT_SYMBOL(vlan_dev_vlan_id);
 117
 118 __be16 vlan_dev_vlan_proto(const struct net_device *dev)
 119 {
 120         return vlan_dev_priv(dev)->vlan_proto;
 121 }
 122 EXPORT_SYMBOL(vlan_dev_vlan_proto);
 123
 124 /*
 125  * vlan info and vid list
 126  */
 127
 128 static void vlan_group_free(struct vlan_group *grp)
 129 {
 130         int i, j;
 131
 132         for (i = 0; i < VLAN_PROTO_NUM; i++)
 133                 for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
 134                         kfree(grp->vlan_devices_arrays[i][j]);
 135 }
 136
 137 static void vlan_info_free(struct vlan_info *vlan_info)
 138 {
 139         vlan_group_free(&vlan_info->grp);
 140         kfree(vlan_info);
 141 }
 142
 143 static void vlan_info_rcu_free(struct rcu_head *rcu)
 144 {
 145         vlan_info_free(container_of(rcu, struct vlan_info, rcu));
 146 }
 147
 148 static struct vlan_info *vlan_info_alloc(struct net_device *dev)
 149 {
 150         struct vlan_info *vlan_info;
 151
 152         vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
 153         if (!vlan_info)
 154                 return NULL;
 155
 156         vlan_info->real_dev = dev;
 157         INIT_LIST_HEAD(&vlan_info->vid_list);
 158         return vlan_info;
 159 }
 160
 161 struct vlan_vid_info {
 162         struct list_head list;
 163         __be16 proto;
 164         u16 vid;
 165         int refcount;
 166 };
 167
 168 static bool vlan_hw_filter_capable(const struct net_device *dev, __be16 proto)
 169 {
 170         if (proto == htons(ETH_P_8021Q) &&
 171             dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
 172                 return true;
 173         if (proto == htons(ETH_P_8021AD) &&
 174             dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
 175                 return true;
 176         return false;
 177 }
 178
 179 static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
 180                                                __be16 proto, u16 vid)
 181 {
 182         struct vlan_vid_info *vid_info;
 183
 184         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
 185                 if (vid_info->proto == proto && vid_info->vid == vid)
 186                         return vid_info;
 187         }
 188         return NULL;
 189 }
 190
 191 static struct vlan_vid_info *vlan_vid_info_alloc(__be16 proto, u16 vid)
 192 {
 193         struct vlan_vid_info *vid_info;
 194
 195         vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
 196         if (!vid_info)
 197                 return NULL;
 198         vid_info->proto = proto;
 199         vid_info->vid = vid;
 200
 201         return vid_info;
 202 }
 203
 204 static int vlan_add_rx_filter_info(struct net_device *dev, __be16 proto, u16 vid)
 205 {
 206         if (!vlan_hw_filter_capable(dev, proto))
 207                 return 0;
 208
 209         if (netif_device_present(dev))
 210                 return dev->netdev_ops->ndo_vlan_rx_add_vid(dev, proto, vid);
 211         else
 212                 return -ENODEV;
 213 }
 214
 215 static int vlan_kill_rx_filter_info(struct net_device *dev, __be16 proto, u16 vid)
 216 {
 217         if (!vlan_hw_filter_capable(dev, proto))
 218                 return 0;
 219
 220         if (netif_device_present(dev))
 221                 return dev->netdev_ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
 222         else
 223                 return -ENODEV;
 224 }
 225
 226 int vlan_filter_push_vids(struct vlan_info *vlan_info, __be16 proto)
 227 {
 228         struct net_device *real_dev = vlan_info->real_dev;
 229         struct vlan_vid_info *vlan_vid_info;
 230         int err;
 231
 232         list_for_each_entry(vlan_vid_info, &vlan_info->vid_list, list) {
 233                 if (vlan_vid_info->proto == proto) {
 234                         err = vlan_add_rx_filter_info(real_dev, proto,
 235                                                       vlan_vid_info->vid);
 236                         if (err)
 237                                 goto unwind;
 238                 }
 239         }
 240
 241         return 0;
 242
 243 unwind:
 244         list_for_each_entry_continue_reverse(vlan_vid_info,
 245                                              &vlan_info->vid_list, list) {
 246                 if (vlan_vid_info->proto == proto)
 247                         vlan_kill_rx_filter_info(real_dev, proto,
 248                                                  vlan_vid_info->vid);
 249         }
 250
 251         return err;
 252 }
 253 EXPORT_SYMBOL(vlan_filter_push_vids);
 254
 255 void vlan_filter_drop_vids(struct vlan_info *vlan_info, __be16 proto)
 256 {
 257         struct vlan_vid_info *vlan_vid_info;
 258
 259         list_for_each_entry(vlan_vid_info, &vlan_info->vid_list, list)
 260                 if (vlan_vid_info->proto == proto)
 261                         vlan_kill_rx_filter_info(vlan_info->real_dev,
 262                                                  vlan_vid_info->proto,
 263                                                  vlan_vid_info->vid);
 264 }
 265 EXPORT_SYMBOL(vlan_filter_drop_vids);
 266
 267 static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
 268                           struct vlan_vid_info **pvid_info)
 269 {
 270         struct net_device *dev = vlan_info->real_dev;
 271         struct vlan_vid_info *vid_info;
 272         int err;
 273
 274         vid_info = vlan_vid_info_alloc(proto, vid);
 275         if (!vid_info)
 276                 return -ENOMEM;
 277
 278         err = vlan_add_rx_filter_info(dev, proto, vid);
 279         if (err) {
 280                 kfree(vid_info);
 281                 return err;
 282         }
 283
 284         list_add(&vid_info->list, &vlan_info->vid_list);
 285         vlan_info->nr_vids++;
 286         *pvid_info = vid_info;
 287         return 0;
 288 }
 289
 290 int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
 291 {
 292         struct vlan_info *vlan_info;
 293         struct vlan_vid_info *vid_info;
 294         bool vlan_info_created = false;
 295         int err;
 296
 297         ASSERT_RTNL();
 298
 299         vlan_info = rtnl_dereference(dev->vlan_info);
 300         if (!vlan_info) {
 301                 vlan_info = vlan_info_alloc(dev);
 302                 if (!vlan_info)
 303                         return -ENOMEM;
 304                 vlan_info_created = true;
 305         }
 306         vid_info = vlan_vid_info_get(vlan_info, proto, vid);
 307         if (!vid_info) {
 308                 err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
 309                 if (err)
 310                         goto out_free_vlan_info;
 311         }
 312         vid_info->refcount++;
 313
 314         if (vlan_info_created)
 315                 rcu_assign_pointer(dev->vlan_info, vlan_info);
 316
 317         return 0;
 318
 319 out_free_vlan_info:
 320         if (vlan_info_created)
 321                 kfree(vlan_info);
 322         return err;
 323 }
 324 EXPORT_SYMBOL(vlan_vid_add);
 325
 326 static void __vlan_vid_del(struct vlan_info *vlan_info,
 327                            struct vlan_vid_info *vid_info)
 328 {
 329         struct net_device *dev = vlan_info->real_dev;
 330         __be16 proto = vid_info->proto;
 331         u16 vid = vid_info->vid;
 332         int err;
 333
 334         err = vlan_kill_rx_filter_info(dev, proto, vid);
 335         if (err)
 336                 pr_warn("failed to kill vid %04x/%d for device %s\n",
 337                         proto, vid, dev->name);
 338
 339         list_del(&vid_info->list);
 340         kfree(vid_info);
 341         vlan_info->nr_vids--;
 342 }
 343
 344 void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
 345 {
 346         struct vlan_info *vlan_info;
 347         struct vlan_vid_info *vid_info;
 348
 349         ASSERT_RTNL();
 350
 351         vlan_info = rtnl_dereference(dev->vlan_info);
 352         if (!vlan_info)
 353                 return;
 354
 355         vid_info = vlan_vid_info_get(vlan_info, proto, vid);
 356         if (!vid_info)
 357                 return;
 358         vid_info->refcount--;
 359         if (vid_info->refcount == 0) {
 360                 __vlan_vid_del(vlan_info, vid_info);
 361                 if (vlan_info->nr_vids == 0) {
 362                         RCU_INIT_POINTER(dev->vlan_info, NULL);
 363                         call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
 364                 }
 365         }
 366 }
 367 EXPORT_SYMBOL(vlan_vid_del);
 368
 369 int vlan_vids_add_by_dev(struct net_device *dev,
 370                          const struct net_device *by_dev)
 371 {
 372         struct vlan_vid_info *vid_info;
 373         struct vlan_info *vlan_info;
 374         int err;
 375
 376         ASSERT_RTNL();
 377
 378         vlan_info = rtnl_dereference(by_dev->vlan_info);
 379         if (!vlan_info)
 380                 return 0;
 381
 382         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
 383                 err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
 384                 if (err)
 385                         goto unwind;
 386         }
 387         return 0;
 388
 389 unwind:
 390         list_for_each_entry_continue_reverse(vid_info,
 391                                              &vlan_info->vid_list,
 392                                              list) {
 393                 vlan_vid_del(dev, vid_info->proto, vid_info->vid);
 394         }
 395
 396         return err;
 397 }
 398 EXPORT_SYMBOL(vlan_vids_add_by_dev);
 399
 400 void vlan_vids_del_by_dev(struct net_device *dev,
 401                           const struct net_device *by_dev)
 402 {
 403         struct vlan_vid_info *vid_info;
 404         struct vlan_info *vlan_info;
 405
 406         ASSERT_RTNL();
 407
 408         vlan_info = rtnl_dereference(by_dev->vlan_info);
 409         if (!vlan_info)
 410                 return;
 411
 412         list_for_each_entry(vid_info, &vlan_info->vid_list, list)
 413                 vlan_vid_del(dev, vid_info->proto, vid_info->vid);
 414 }
 415 EXPORT_SYMBOL(vlan_vids_del_by_dev);
 416
 417 bool vlan_uses_dev(const struct net_device *dev)
 418 {
 419         struct vlan_info *vlan_info;
 420
 421         ASSERT_RTNL();
 422
 423         vlan_info = rtnl_dereference(dev->vlan_info);
 424         if (!vlan_info)
 425                 return false;
 426         return vlan_info->grp.nr_vlan_devs ? true : false;
 427 }
 428 EXPORT_SYMBOL(vlan_uses_dev);