net/8021q/vlan_core.c

   1 #include <linux/skbuff.h>
   2 #include <linux/netdevice.h>
   3 #include <linux/if_vlan.h>
   4 #include <linux/netpoll.h>
   5 #include <linux/export.h>
   6 #include "vlan.h"
   7
   8 bool vlan_do_receive(struct sk_buff **skbp)
   9 {
  10         struct sk_buff *skb = *skbp;
  11         __be16 vlan_proto = skb->vlan_proto;
  12         u16 vlan_id = skb_vlan_tag_get_id(skb);
  13         struct net_device *vlan_dev;
  14         struct vlan_pcpu_stats *rx_stats;
  15
  16         vlan_dev = vlan_find_dev(skb->dev, vlan_proto, vlan_id);
  17         if (!vlan_dev)
  18                 return false;
  19
  20         skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
  21         if (unlikely(!skb))
  22                 return false;
  23
  24         if (unlikely(!(vlan_dev->flags & IFF_UP))) {
  25                 kfree_skb(skb);
  26                 *skbp = NULL;
  27                 return false;
  28         }
  29
  30         skb->dev = vlan_dev;
  31         if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) {
  32                 /* Our lower layer thinks this is not local, let's make sure.
  33                  * This allows the VLAN to have a different MAC than the
  34                  * underlying device, and still route correctly. */
  35                 if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
  36                         skb->pkt_type = PACKET_HOST;
  37         }
  38
  39         if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR) &&
  40             !netif_is_macvlan_port(vlan_dev) &&
  41             !netif_is_bridge_port(vlan_dev)) {
  42                 unsigned int offset = skb->data - skb_mac_header(skb);
  43
  44                 /*
  45                  * vlan_insert_tag expect skb->data pointing to mac header.
  46                  * So change skb->data before calling it and change back to
  47                  * original position later
  48                  */
  49                 skb_push(skb, offset);
  50                 skb = *skbp = vlan_insert_tag(skb, skb->vlan_proto,
  51                                               skb->vlan_tci);
  52                 if (!skb)
  53                         return false;
  54                 skb_pull(skb, offset + VLAN_HLEN);
  55                 skb_reset_mac_len(skb);
  56         }
  57
  58         skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
  59         skb->vlan_tci = 0;
  60
  61         rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
  62
  63         u64_stats_update_begin(&rx_stats->syncp);
  64         rx_stats->rx_packets++;
  65         rx_stats->rx_bytes += skb->len;
  66         if (skb->pkt_type == PACKET_MULTICAST)
  67                 rx_stats->rx_multicast++;
  68         u64_stats_update_end(&rx_stats->syncp);
  69
  70         return true;
  71 }
  72
  73 /* Must be invoked with rcu_read_lock. */
  74 struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
  75                                         __be16 vlan_proto, u16 vlan_id)
  76 {
  77         struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
  78
  79         if (vlan_info) {
  80                 return vlan_group_get_device(&vlan_info->grp,
  81                                              vlan_proto, vlan_id);
  82         } else {
  83                 /*
  84                  * Lower devices of master uppers (bonding, team) do not have
  85                  * grp assigned to themselves. Grp is assigned to upper device
  86                  * instead.
  87                  */
  88                 struct net_device *upper_dev;
  89
  90                 upper_dev = netdev_master_upper_dev_get_rcu(dev);
  91                 if (upper_dev)
  92                         return __vlan_find_dev_deep_rcu(upper_dev,
  93                                                     vlan_proto, vlan_id);
  94         }
  95
  96         return NULL;
  97 }
  98 EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
  99
 100 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
 101 {
 102         struct net_device *ret = vlan_dev_priv(dev)->real_dev;
 103
 104         while (is_vlan_dev(ret))
 105                 ret = vlan_dev_priv(ret)->real_dev;
 106
 107         return ret;
 108 }
 109 EXPORT_SYMBOL(vlan_dev_real_dev);
 110
 111 u16 vlan_dev_vlan_id(const struct net_device *dev)
 112 {
 113         return vlan_dev_priv(dev)->vlan_id;
 114 }
 115 EXPORT_SYMBOL(vlan_dev_vlan_id);
 116
 117 __be16 vlan_dev_vlan_proto(const struct net_device *dev)
 118 {
 119         return vlan_dev_priv(dev)->vlan_proto;
 120 }
 121 EXPORT_SYMBOL(vlan_dev_vlan_proto);
 122
 123 /*
 124  * vlan info and vid list
 125  */
 126
 127 static void vlan_group_free(struct vlan_group *grp)
 128 {
 129         int i, j;
 130
 131         for (i = 0; i < VLAN_PROTO_NUM; i++)
 132                 for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
 133                         kfree(grp->vlan_devices_arrays[i][j]);
 134 }
 135
 136 static void vlan_info_free(struct vlan_info *vlan_info)
 137 {
 138         vlan_group_free(&vlan_info->grp);
 139         kfree(vlan_info);
 140 }
 141
 142 static void vlan_info_rcu_free(struct rcu_head *rcu)
 143 {
 144         vlan_info_free(container_of(rcu, struct vlan_info, rcu));
 145 }
 146
 147 static struct vlan_info *vlan_info_alloc(struct net_device *dev)
 148 {
 149         struct vlan_info *vlan_info;
 150
 151         vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
 152         if (!vlan_info)
 153                 return NULL;
 154
 155         vlan_info->real_dev = dev;
 156         INIT_LIST_HEAD(&vlan_info->vid_list);
 157         return vlan_info;
 158 }
 159
 160 struct vlan_vid_info {
 161         struct list_head list;
 162         __be16 proto;
 163         u16 vid;
 164         int refcount;
 165 };
 166
 167 static bool vlan_hw_filter_capable(const struct net_device *dev,
 168                                      const struct vlan_vid_info *vid_info)
 169 {
 170         if (vid_info->proto == htons(ETH_P_8021Q) &&
 171             dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
 172                 return true;
 173         if (vid_info->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_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
 205                           struct vlan_vid_info **pvid_info)
 206 {
 207         struct net_device *dev = vlan_info->real_dev;
 208         const struct net_device_ops *ops = dev->netdev_ops;
 209         struct vlan_vid_info *vid_info;
 210         int err;
 211
 212         vid_info = vlan_vid_info_alloc(proto, vid);
 213         if (!vid_info)
 214                 return -ENOMEM;
 215
 216         if (vlan_hw_filter_capable(dev, vid_info)) {
 217                 if (netif_device_present(dev))
 218                         err = ops->ndo_vlan_rx_add_vid(dev, proto, vid);
 219                 else
 220                         err = -ENODEV;
 221                 if (err) {
 222                         kfree(vid_info);
 223                         return err;
 224                 }
 225         }
 226         list_add(&vid_info->list, &vlan_info->vid_list);
 227         vlan_info->nr_vids++;
 228         *pvid_info = vid_info;
 229         return 0;
 230 }
 231
 232 int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
 233 {
 234         struct vlan_info *vlan_info;
 235         struct vlan_vid_info *vid_info;
 236         bool vlan_info_created = false;
 237         int err;
 238
 239         ASSERT_RTNL();
 240
 241         vlan_info = rtnl_dereference(dev->vlan_info);
 242         if (!vlan_info) {
 243                 vlan_info = vlan_info_alloc(dev);
 244                 if (!vlan_info)
 245                         return -ENOMEM;
 246                 vlan_info_created = true;
 247         }
 248         vid_info = vlan_vid_info_get(vlan_info, proto, vid);
 249         if (!vid_info) {
 250                 err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
 251                 if (err)
 252                         goto out_free_vlan_info;
 253         }
 254         vid_info->refcount++;
 255
 256         if (vlan_info_created)
 257                 rcu_assign_pointer(dev->vlan_info, vlan_info);
 258
 259         return 0;
 260
 261 out_free_vlan_info:
 262         if (vlan_info_created)
 263                 kfree(vlan_info);
 264         return err;
 265 }
 266 EXPORT_SYMBOL(vlan_vid_add);
 267
 268 static void __vlan_vid_del(struct vlan_info *vlan_info,
 269                            struct vlan_vid_info *vid_info)
 270 {
 271         struct net_device *dev = vlan_info->real_dev;
 272         const struct net_device_ops *ops = dev->netdev_ops;
 273         __be16 proto = vid_info->proto;
 274         u16 vid = vid_info->vid;
 275         int err;
 276
 277         if (vlan_hw_filter_capable(dev, vid_info)) {
 278                 if (netif_device_present(dev))
 279                         err = ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
 280                 else
 281                         err = -ENODEV;
 282                 if (err) {
 283                         pr_warn("failed to kill vid %04x/%d for device %s\n",
 284                                 proto, vid, dev->name);
 285                 }
 286         }
 287         list_del(&vid_info->list);
 288         kfree(vid_info);
 289         vlan_info->nr_vids--;
 290 }
 291
 292 void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
 293 {
 294         struct vlan_info *vlan_info;
 295         struct vlan_vid_info *vid_info;
 296
 297         ASSERT_RTNL();
 298
 299         vlan_info = rtnl_dereference(dev->vlan_info);
 300         if (!vlan_info)
 301                 return;
 302
 303         vid_info = vlan_vid_info_get(vlan_info, proto, vid);
 304         if (!vid_info)
 305                 return;
 306         vid_info->refcount--;
 307         if (vid_info->refcount == 0) {
 308                 __vlan_vid_del(vlan_info, vid_info);
 309                 if (vlan_info->nr_vids == 0) {
 310                         RCU_INIT_POINTER(dev->vlan_info, NULL);
 311                         call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
 312                 }
 313         }
 314 }
 315 EXPORT_SYMBOL(vlan_vid_del);
 316
 317 int vlan_vids_add_by_dev(struct net_device *dev,
 318                          const struct net_device *by_dev)
 319 {
 320         struct vlan_vid_info *vid_info;
 321         struct vlan_info *vlan_info;
 322         int err;
 323
 324         ASSERT_RTNL();
 325
 326         vlan_info = rtnl_dereference(by_dev->vlan_info);
 327         if (!vlan_info)
 328                 return 0;
 329
 330         list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
 331                 err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
 332                 if (err)
 333                         goto unwind;
 334         }
 335         return 0;
 336
 337 unwind:
 338         list_for_each_entry_continue_reverse(vid_info,
 339                                              &vlan_info->vid_list,
 340                                              list) {
 341                 vlan_vid_del(dev, vid_info->proto, vid_info->vid);
 342         }
 343
 344         return err;
 345 }
 346 EXPORT_SYMBOL(vlan_vids_add_by_dev);
 347
 348 void vlan_vids_del_by_dev(struct net_device *dev,
 349                           const struct net_device *by_dev)
 350 {
 351         struct vlan_vid_info *vid_info;
 352         struct vlan_info *vlan_info;
 353
 354         ASSERT_RTNL();
 355
 356         vlan_info = rtnl_dereference(by_dev->vlan_info);
 357         if (!vlan_info)
 358                 return;
 359
 360         list_for_each_entry(vid_info, &vlan_info->vid_list, list)
 361                 vlan_vid_del(dev, vid_info->proto, vid_info->vid);
 362 }
 363 EXPORT_SYMBOL(vlan_vids_del_by_dev);
 364
 365 bool vlan_uses_dev(const struct net_device *dev)
 366 {
 367         struct vlan_info *vlan_info;
 368
 369         ASSERT_RTNL();
 370
 371         vlan_info = rtnl_dereference(dev->vlan_info);
 372         if (!vlan_info)
 373                 return false;
 374         return vlan_info->grp.nr_vlan_devs ? true : false;
 375 }
 376 EXPORT_SYMBOL(vlan_uses_dev);