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