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 u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK; 12 struct net_device *vlan_dev; 13 struct vlan_pcpu_stats *rx_stats; 14 15 vlan_dev = vlan_find_dev(skb->dev, vlan_id); 16 if (!vlan_dev) 17 return false; 18 19 skb = *skbp = skb_share_check(skb, GFP_ATOMIC); 20 if (unlikely(!skb)) 21 return false; 22 23 skb->dev = vlan_dev; 24 if (skb->pkt_type == PACKET_OTHERHOST) { 25 /* Our lower layer thinks this is not local, let's make sure. 26 * This allows the VLAN to have a different MAC than the 27 * underlying device, and still route correctly. */ 28 if (ether_addr_equal(eth_hdr(skb)->h_dest, vlan_dev->dev_addr)) 29 skb->pkt_type = PACKET_HOST; 30 } 31 32 if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) { 33 unsigned int offset = skb->data - skb_mac_header(skb); 34 35 /* 36 * vlan_insert_tag expect skb->data pointing to mac header. 37 * So change skb->data before calling it and change back to 38 * original position later 39 */ 40 skb_push(skb, offset); 41 skb = *skbp = vlan_insert_tag(skb, skb->vlan_tci); 42 if (!skb) 43 return false; 44 skb_pull(skb, offset + VLAN_HLEN); 45 skb_reset_mac_len(skb); 46 } 47 48 skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci); 49 skb->vlan_tci = 0; 50 51 rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats); 52 53 u64_stats_update_begin(&rx_stats->syncp); 54 rx_stats->rx_packets++; 55 rx_stats->rx_bytes += skb->len; 56 if (skb->pkt_type == PACKET_MULTICAST) 57 rx_stats->rx_multicast++; 58 u64_stats_update_end(&rx_stats->syncp); 59 60 return true; 61 } 62 63 /* Must be invoked with rcu_read_lock. */ 64 struct net_device *__vlan_find_dev_deep(struct net_device *dev, 65 u16 vlan_id) 66 { 67 struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info); 68 69 if (vlan_info) { 70 return vlan_group_get_device(&vlan_info->grp, vlan_id); 71 } else { 72 /* 73 * Lower devices of master uppers (bonding, team) do not have 74 * grp assigned to themselves. Grp is assigned to upper device 75 * instead. 76 */ 77 struct net_device *upper_dev; 78 79 upper_dev = netdev_master_upper_dev_get_rcu(dev); 80 if (upper_dev) 81 return __vlan_find_dev_deep(upper_dev, vlan_id); 82 } 83 84 return NULL; 85 } 86 EXPORT_SYMBOL(__vlan_find_dev_deep); 87 88 struct net_device *vlan_dev_real_dev(const struct net_device *dev) 89 { 90 return vlan_dev_priv(dev)->real_dev; 91 } 92 EXPORT_SYMBOL(vlan_dev_real_dev); 93 94 u16 vlan_dev_vlan_id(const struct net_device *dev) 95 { 96 return vlan_dev_priv(dev)->vlan_id; 97 } 98 EXPORT_SYMBOL(vlan_dev_vlan_id); 99 100 static struct sk_buff *vlan_reorder_header(struct sk_buff *skb) 101 { 102 if (skb_cow(skb, skb_headroom(skb)) < 0) 103 return NULL; 104 memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN); 105 skb->mac_header += VLAN_HLEN; 106 return skb; 107 } 108 109 struct sk_buff *vlan_untag(struct sk_buff *skb) 110 { 111 struct vlan_hdr *vhdr; 112 u16 vlan_tci; 113 114 if (unlikely(vlan_tx_tag_present(skb))) { 115 /* vlan_tci is already set-up so leave this for another time */ 116 return skb; 117 } 118 119 skb = skb_share_check(skb, GFP_ATOMIC); 120 if (unlikely(!skb)) 121 goto err_free; 122 123 if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) 124 goto err_free; 125 126 vhdr = (struct vlan_hdr *) skb->data; 127 vlan_tci = ntohs(vhdr->h_vlan_TCI); 128 __vlan_hwaccel_put_tag(skb, vlan_tci); 129 130 skb_pull_rcsum(skb, VLAN_HLEN); 131 vlan_set_encap_proto(skb, vhdr); 132 133 skb = vlan_reorder_header(skb); 134 if (unlikely(!skb)) 135 goto err_free; 136 137 skb_reset_network_header(skb); 138 skb_reset_transport_header(skb); 139 skb_reset_mac_len(skb); 140 141 return skb; 142 143 err_free: 144 kfree_skb(skb); 145 return NULL; 146 } 147 EXPORT_SYMBOL(vlan_untag); 148 149 150 /* 151 * vlan info and vid list 152 */ 153 154 static void vlan_group_free(struct vlan_group *grp) 155 { 156 int i; 157 158 for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++) 159 kfree(grp->vlan_devices_arrays[i]); 160 } 161 162 static void vlan_info_free(struct vlan_info *vlan_info) 163 { 164 vlan_group_free(&vlan_info->grp); 165 kfree(vlan_info); 166 } 167 168 static void vlan_info_rcu_free(struct rcu_head *rcu) 169 { 170 vlan_info_free(container_of(rcu, struct vlan_info, rcu)); 171 } 172 173 static struct vlan_info *vlan_info_alloc(struct net_device *dev) 174 { 175 struct vlan_info *vlan_info; 176 177 vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL); 178 if (!vlan_info) 179 return NULL; 180 181 vlan_info->real_dev = dev; 182 INIT_LIST_HEAD(&vlan_info->vid_list); 183 return vlan_info; 184 } 185 186 struct vlan_vid_info { 187 struct list_head list; 188 unsigned short vid; 189 int refcount; 190 }; 191 192 static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info, 193 unsigned short vid) 194 { 195 struct vlan_vid_info *vid_info; 196 197 list_for_each_entry(vid_info, &vlan_info->vid_list, list) { 198 if (vid_info->vid == vid) 199 return vid_info; 200 } 201 return NULL; 202 } 203 204 static struct vlan_vid_info *vlan_vid_info_alloc(unsigned short vid) 205 { 206 struct vlan_vid_info *vid_info; 207 208 vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL); 209 if (!vid_info) 210 return NULL; 211 vid_info->vid = vid; 212 213 return vid_info; 214 } 215 216 static int __vlan_vid_add(struct vlan_info *vlan_info, unsigned short vid, 217 struct vlan_vid_info **pvid_info) 218 { 219 struct net_device *dev = vlan_info->real_dev; 220 const struct net_device_ops *ops = dev->netdev_ops; 221 struct vlan_vid_info *vid_info; 222 int err; 223 224 vid_info = vlan_vid_info_alloc(vid); 225 if (!vid_info) 226 return -ENOMEM; 227 228 if (dev->features & NETIF_F_HW_VLAN_FILTER) { 229 err = ops->ndo_vlan_rx_add_vid(dev, vid); 230 if (err) { 231 kfree(vid_info); 232 return err; 233 } 234 } 235 list_add(&vid_info->list, &vlan_info->vid_list); 236 vlan_info->nr_vids++; 237 *pvid_info = vid_info; 238 return 0; 239 } 240 241 int vlan_vid_add(struct net_device *dev, unsigned short vid) 242 { 243 struct vlan_info *vlan_info; 244 struct vlan_vid_info *vid_info; 245 bool vlan_info_created = false; 246 int err; 247 248 ASSERT_RTNL(); 249 250 vlan_info = rtnl_dereference(dev->vlan_info); 251 if (!vlan_info) { 252 vlan_info = vlan_info_alloc(dev); 253 if (!vlan_info) 254 return -ENOMEM; 255 vlan_info_created = true; 256 } 257 vid_info = vlan_vid_info_get(vlan_info, vid); 258 if (!vid_info) { 259 err = __vlan_vid_add(vlan_info, vid, &vid_info); 260 if (err) 261 goto out_free_vlan_info; 262 } 263 vid_info->refcount++; 264 265 if (vlan_info_created) 266 rcu_assign_pointer(dev->vlan_info, vlan_info); 267 268 return 0; 269 270 out_free_vlan_info: 271 if (vlan_info_created) 272 kfree(vlan_info); 273 return err; 274 } 275 EXPORT_SYMBOL(vlan_vid_add); 276 277 static void __vlan_vid_del(struct vlan_info *vlan_info, 278 struct vlan_vid_info *vid_info) 279 { 280 struct net_device *dev = vlan_info->real_dev; 281 const struct net_device_ops *ops = dev->netdev_ops; 282 unsigned short vid = vid_info->vid; 283 int err; 284 285 if (dev->features & NETIF_F_HW_VLAN_FILTER) { 286 err = ops->ndo_vlan_rx_kill_vid(dev, vid); 287 if (err) { 288 pr_warn("failed to kill vid %d for device %s\n", 289 vid, dev->name); 290 } 291 } 292 list_del(&vid_info->list); 293 kfree(vid_info); 294 vlan_info->nr_vids--; 295 } 296 297 void vlan_vid_del(struct net_device *dev, unsigned short vid) 298 { 299 struct vlan_info *vlan_info; 300 struct vlan_vid_info *vid_info; 301 302 ASSERT_RTNL(); 303 304 vlan_info = rtnl_dereference(dev->vlan_info); 305 if (!vlan_info) 306 return; 307 308 vid_info = vlan_vid_info_get(vlan_info, vid); 309 if (!vid_info) 310 return; 311 vid_info->refcount--; 312 if (vid_info->refcount == 0) { 313 __vlan_vid_del(vlan_info, vid_info); 314 if (vlan_info->nr_vids == 0) { 315 RCU_INIT_POINTER(dev->vlan_info, NULL); 316 call_rcu(&vlan_info->rcu, vlan_info_rcu_free); 317 } 318 } 319 } 320 EXPORT_SYMBOL(vlan_vid_del); 321 322 int vlan_vids_add_by_dev(struct net_device *dev, 323 const struct net_device *by_dev) 324 { 325 struct vlan_vid_info *vid_info; 326 struct vlan_info *vlan_info; 327 int err; 328 329 ASSERT_RTNL(); 330 331 vlan_info = rtnl_dereference(by_dev->vlan_info); 332 if (!vlan_info) 333 return 0; 334 335 list_for_each_entry(vid_info, &vlan_info->vid_list, list) { 336 err = vlan_vid_add(dev, vid_info->vid); 337 if (err) 338 goto unwind; 339 } 340 return 0; 341 342 unwind: 343 list_for_each_entry_continue_reverse(vid_info, 344 &vlan_info->vid_list, 345 list) { 346 vlan_vid_del(dev, vid_info->vid); 347 } 348 349 return err; 350 } 351 EXPORT_SYMBOL(vlan_vids_add_by_dev); 352 353 void vlan_vids_del_by_dev(struct net_device *dev, 354 const struct net_device *by_dev) 355 { 356 struct vlan_vid_info *vid_info; 357 struct vlan_info *vlan_info; 358 359 ASSERT_RTNL(); 360 361 vlan_info = rtnl_dereference(by_dev->vlan_info); 362 if (!vlan_info) 363 return; 364 365 list_for_each_entry(vid_info, &vlan_info->vid_list, list) 366 vlan_vid_del(dev, vid_info->vid); 367 } 368 EXPORT_SYMBOL(vlan_vids_del_by_dev); 369 370 bool vlan_uses_dev(const struct net_device *dev) 371 { 372 struct vlan_info *vlan_info; 373 374 ASSERT_RTNL(); 375 376 vlan_info = rtnl_dereference(dev->vlan_info); 377 if (!vlan_info) 378 return false; 379 return vlan_info->grp.nr_vlan_devs ? true : false; 380 } 381 EXPORT_SYMBOL(vlan_uses_dev); 382