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
8bool 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 = vlan_tx_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	skb->dev = vlan_dev;
25	if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) {
26		/* Our lower layer thinks this is not local, let's make sure.
27		 * This allows the VLAN to have a different MAC than the
28		 * underlying device, and still route correctly. */
29		if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, 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_proto,
43					      skb->vlan_tci);
44		if (!skb)
45			return false;
46		skb_pull(skb, offset + VLAN_HLEN);
47		skb_reset_mac_len(skb);
48	}
49
50	skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
51	skb->vlan_tci = 0;
52
53	rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
54
55	u64_stats_update_begin(&rx_stats->syncp);
56	rx_stats->rx_packets++;
57	rx_stats->rx_bytes += skb->len;
58	if (skb->pkt_type == PACKET_MULTICAST)
59		rx_stats->rx_multicast++;
60	u64_stats_update_end(&rx_stats->syncp);
61
62	return true;
63}
64
65/* Must be invoked with rcu_read_lock. */
66struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
67					__be16 vlan_proto, u16 vlan_id)
68{
69	struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
70
71	if (vlan_info) {
72		return vlan_group_get_device(&vlan_info->grp,
73					     vlan_proto, vlan_id);
74	} else {
75		/*
76		 * Lower devices of master uppers (bonding, team) do not have
77		 * grp assigned to themselves. Grp is assigned to upper device
78		 * instead.
79		 */
80		struct net_device *upper_dev;
81
82		upper_dev = netdev_master_upper_dev_get_rcu(dev);
83		if (upper_dev)
84			return __vlan_find_dev_deep_rcu(upper_dev,
85						    vlan_proto, vlan_id);
86	}
87
88	return NULL;
89}
90EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
91
92struct net_device *vlan_dev_real_dev(const struct net_device *dev)
93{
94	struct net_device *ret = vlan_dev_priv(dev)->real_dev;
95
96	while (is_vlan_dev(ret))
97		ret = vlan_dev_priv(ret)->real_dev;
98
99	return ret;
100}
101EXPORT_SYMBOL(vlan_dev_real_dev);
102
103u16 vlan_dev_vlan_id(const struct net_device *dev)
104{
105	return vlan_dev_priv(dev)->vlan_id;
106}
107EXPORT_SYMBOL(vlan_dev_vlan_id);
108
109__be16 vlan_dev_vlan_proto(const struct net_device *dev)
110{
111	return vlan_dev_priv(dev)->vlan_proto;
112}
113EXPORT_SYMBOL(vlan_dev_vlan_proto);
114
115/*
116 * vlan info and vid list
117 */
118
119static void vlan_group_free(struct vlan_group *grp)
120{
121	int i, j;
122
123	for (i = 0; i < VLAN_PROTO_NUM; i++)
124		for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
125			kfree(grp->vlan_devices_arrays[i][j]);
126}
127
128static void vlan_info_free(struct vlan_info *vlan_info)
129{
130	vlan_group_free(&vlan_info->grp);
131	kfree(vlan_info);
132}
133
134static void vlan_info_rcu_free(struct rcu_head *rcu)
135{
136	vlan_info_free(container_of(rcu, struct vlan_info, rcu));
137}
138
139static struct vlan_info *vlan_info_alloc(struct net_device *dev)
140{
141	struct vlan_info *vlan_info;
142
143	vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
144	if (!vlan_info)
145		return NULL;
146
147	vlan_info->real_dev = dev;
148	INIT_LIST_HEAD(&vlan_info->vid_list);
149	return vlan_info;
150}
151
152struct vlan_vid_info {
153	struct list_head list;
154	__be16 proto;
155	u16 vid;
156	int refcount;
157};
158
159static bool vlan_hw_filter_capable(const struct net_device *dev,
160				     const struct vlan_vid_info *vid_info)
161{
162	if (vid_info->proto == htons(ETH_P_8021Q) &&
163	    dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
164		return true;
165	if (vid_info->proto == htons(ETH_P_8021AD) &&
166	    dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
167		return true;
168	return false;
169}
170
171static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
172					       __be16 proto, u16 vid)
173{
174	struct vlan_vid_info *vid_info;
175
176	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
177		if (vid_info->proto == proto && vid_info->vid == vid)
178			return vid_info;
179	}
180	return NULL;
181}
182
183static struct vlan_vid_info *vlan_vid_info_alloc(__be16 proto, u16 vid)
184{
185	struct vlan_vid_info *vid_info;
186
187	vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
188	if (!vid_info)
189		return NULL;
190	vid_info->proto = proto;
191	vid_info->vid = vid;
192
193	return vid_info;
194}
195
196static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
197			  struct vlan_vid_info **pvid_info)
198{
199	struct net_device *dev = vlan_info->real_dev;
200	const struct net_device_ops *ops = dev->netdev_ops;
201	struct vlan_vid_info *vid_info;
202	int err;
203
204	vid_info = vlan_vid_info_alloc(proto, vid);
205	if (!vid_info)
206		return -ENOMEM;
207
208	if (vlan_hw_filter_capable(dev, vid_info)) {
209		err =  ops->ndo_vlan_rx_add_vid(dev, proto, vid);
210		if (err) {
211			kfree(vid_info);
212			return err;
213		}
214	}
215	list_add(&vid_info->list, &vlan_info->vid_list);
216	vlan_info->nr_vids++;
217	*pvid_info = vid_info;
218	return 0;
219}
220
221int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
222{
223	struct vlan_info *vlan_info;
224	struct vlan_vid_info *vid_info;
225	bool vlan_info_created = false;
226	int err;
227
228	ASSERT_RTNL();
229
230	vlan_info = rtnl_dereference(dev->vlan_info);
231	if (!vlan_info) {
232		vlan_info = vlan_info_alloc(dev);
233		if (!vlan_info)
234			return -ENOMEM;
235		vlan_info_created = true;
236	}
237	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
238	if (!vid_info) {
239		err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
240		if (err)
241			goto out_free_vlan_info;
242	}
243	vid_info->refcount++;
244
245	if (vlan_info_created)
246		rcu_assign_pointer(dev->vlan_info, vlan_info);
247
248	return 0;
249
250out_free_vlan_info:
251	if (vlan_info_created)
252		kfree(vlan_info);
253	return err;
254}
255EXPORT_SYMBOL(vlan_vid_add);
256
257static void __vlan_vid_del(struct vlan_info *vlan_info,
258			   struct vlan_vid_info *vid_info)
259{
260	struct net_device *dev = vlan_info->real_dev;
261	const struct net_device_ops *ops = dev->netdev_ops;
262	__be16 proto = vid_info->proto;
263	u16 vid = vid_info->vid;
264	int err;
265
266	if (vlan_hw_filter_capable(dev, vid_info)) {
267		err = ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
268		if (err) {
269			pr_warn("failed to kill vid %04x/%d for device %s\n",
270				proto, vid, dev->name);
271		}
272	}
273	list_del(&vid_info->list);
274	kfree(vid_info);
275	vlan_info->nr_vids--;
276}
277
278void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
279{
280	struct vlan_info *vlan_info;
281	struct vlan_vid_info *vid_info;
282
283	ASSERT_RTNL();
284
285	vlan_info = rtnl_dereference(dev->vlan_info);
286	if (!vlan_info)
287		return;
288
289	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
290	if (!vid_info)
291		return;
292	vid_info->refcount--;
293	if (vid_info->refcount == 0) {
294		__vlan_vid_del(vlan_info, vid_info);
295		if (vlan_info->nr_vids == 0) {
296			RCU_INIT_POINTER(dev->vlan_info, NULL);
297			call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
298		}
299	}
300}
301EXPORT_SYMBOL(vlan_vid_del);
302
303int vlan_vids_add_by_dev(struct net_device *dev,
304			 const struct net_device *by_dev)
305{
306	struct vlan_vid_info *vid_info;
307	struct vlan_info *vlan_info;
308	int err;
309
310	ASSERT_RTNL();
311
312	vlan_info = rtnl_dereference(by_dev->vlan_info);
313	if (!vlan_info)
314		return 0;
315
316	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
317		err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
318		if (err)
319			goto unwind;
320	}
321	return 0;
322
323unwind:
324	list_for_each_entry_continue_reverse(vid_info,
325					     &vlan_info->vid_list,
326					     list) {
327		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
328	}
329
330	return err;
331}
332EXPORT_SYMBOL(vlan_vids_add_by_dev);
333
334void vlan_vids_del_by_dev(struct net_device *dev,
335			  const struct net_device *by_dev)
336{
337	struct vlan_vid_info *vid_info;
338	struct vlan_info *vlan_info;
339
340	ASSERT_RTNL();
341
342	vlan_info = rtnl_dereference(by_dev->vlan_info);
343	if (!vlan_info)
344		return;
345
346	list_for_each_entry(vid_info, &vlan_info->vid_list, list)
347		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
348}
349EXPORT_SYMBOL(vlan_vids_del_by_dev);
350
351bool vlan_uses_dev(const struct net_device *dev)
352{
353	struct vlan_info *vlan_info;
354
355	ASSERT_RTNL();
356
357	vlan_info = rtnl_dereference(dev->vlan_info);
358	if (!vlan_info)
359		return false;
360	return vlan_info->grp.nr_vlan_devs ? true : false;
361}
362EXPORT_SYMBOL(vlan_uses_dev);
363