summaryrefslogtreecommitdiffstats
path: root/net/8021q/vlan_core.c
blob: add69d0fd99d2b34025c0d8fb42f703ca6ea38c0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include <linux/netpoll.h>
#include <linux/export.h>
#include "vlan.h"

bool vlan_do_receive(struct sk_buff **skbp, bool last_handler)
{
	struct sk_buff *skb = *skbp;
	u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK;
	struct net_device *vlan_dev;
	struct vlan_pcpu_stats *rx_stats;

	vlan_dev = vlan_find_dev(skb->dev, vlan_id);
	if (!vlan_dev) {
		/* Only the last call to vlan_do_receive() should change
		 * pkt_type to PACKET_OTHERHOST
		 */
		if (vlan_id && last_handler)
			skb->pkt_type = PACKET_OTHERHOST;
		return false;
	}

	skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
	if (unlikely(!skb))
		return false;

	skb->dev = vlan_dev;
	if (skb->pkt_type == PACKET_OTHERHOST) {
		/* Our lower layer thinks this is not local, let's make sure.
		 * This allows the VLAN to have a different MAC than the
		 * underlying device, and still route correctly. */
		if (ether_addr_equal(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
			skb->pkt_type = PACKET_HOST;
	}

	if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) {
		unsigned int offset = skb->data - skb_mac_header(skb);

		/*
		 * vlan_insert_tag expect skb->data pointing to mac header.
		 * So change skb->data before calling it and change back to
		 * original position later
		 */
		skb_push(skb, offset);
		skb = *skbp = vlan_insert_tag(skb, skb->vlan_tci);
		if (!skb)
			return false;
		skb_pull(skb, offset + VLAN_HLEN);
		skb_reset_mac_len(skb);
	}

	skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
	skb->vlan_tci = 0;

	rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);

	u64_stats_update_begin(&rx_stats->syncp);
	rx_stats->rx_packets++;
	rx_stats->rx_bytes += skb->len;
	if (skb->pkt_type == PACKET_MULTICAST)
		rx_stats->rx_multicast++;
	u64_stats_update_end(&rx_stats->syncp);

	return true;
}

/* Must be invoked with rcu_read_lock or with RTNL. */
struct net_device *__vlan_find_dev_deep(struct net_device *real_dev,
					u16 vlan_id)
{
	struct vlan_info *vlan_info = rcu_dereference_rtnl(real_dev->vlan_info);

	if (vlan_info) {
		return vlan_group_get_device(&vlan_info->grp, vlan_id);
	} else {
		/*
		 * Bonding slaves do not have grp assigned to themselves.
		 * Grp is assigned to bonding master instead.
		 */
		if (netif_is_bond_slave(real_dev))
			return __vlan_find_dev_deep(real_dev->master, vlan_id);
	}

	return NULL;
}
EXPORT_SYMBOL(__vlan_find_dev_deep);

struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
	return vlan_dev_priv(dev)->real_dev;
}
EXPORT_SYMBOL(vlan_dev_real_dev);

u16 vlan_dev_vlan_id(const struct net_device *dev)
{
	return vlan_dev_priv(dev)->vlan_id;
}
EXPORT_SYMBOL(vlan_dev_vlan_id);

static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
{
	if (skb_cow(skb, skb_headroom(skb)) < 0)
		return NULL;
	memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
	skb->mac_header += VLAN_HLEN;
	return skb;
}

struct sk_buff *vlan_untag(struct sk_buff *skb)
{
	struct vlan_hdr *vhdr;
	u16 vlan_tci;

	if (unlikely(vlan_tx_tag_present(skb))) {
		/* vlan_tci is already set-up so leave this for another time */
		return skb;
	}

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (unlikely(!skb))
		goto err_free;

	if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
		goto err_free;

	vhdr = (struct vlan_hdr *) skb->data;
	vlan_tci = ntohs(vhdr->h_vlan_TCI);
	__vlan_hwaccel_put_tag(skb, vlan_tci);

	skb_pull_rcsum(skb, VLAN_HLEN);
	vlan_set_encap_proto(skb, vhdr);

	skb = vlan_reorder_header(skb);
	if (unlikely(!skb))
		goto err_free;

	skb_reset_network_header(skb);
	skb_reset_transport_header(skb);
	skb_reset_mac_len(skb);

	return skb;

err_free:
	kfree_skb(skb);
	return NULL;
}


/*
 * vlan info and vid list
 */

static void vlan_group_free(struct vlan_group *grp)
{
	int i;

	for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
		kfree(grp->vlan_devices_arrays[i]);
}

static void vlan_info_free(struct vlan_info *vlan_info)
{
	vlan_group_free(&vlan_info->grp);
	kfree(vlan_info);
}

static void vlan_info_rcu_free(struct rcu_head *rcu)
{
	vlan_info_free(container_of(rcu, struct vlan_info, rcu));
}

static struct vlan_info *vlan_info_alloc(struct net_device *dev)
{
	struct vlan_info *vlan_info;

	vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
	if (!vlan_info)
		return NULL;

	vlan_info->real_dev = dev;
	INIT_LIST_HEAD(&vlan_info->vid_list);
	return vlan_info;
}

struct vlan_vid_info {
	struct list_head list;
	unsigned short vid;
	int refcount;
};

static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
					       unsigned short vid)
{
	struct vlan_vid_info *vid_info;

	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
		if (vid_info->vid == vid)
			return vid_info;
	}
	return NULL;
}

static struct vlan_vid_info *vlan_vid_info_alloc(unsigned short vid)
{
	struct vlan_vid_info *vid_info;

	vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
	if (!vid_info)
		return NULL;
	vid_info->vid = vid;

	return vid_info;
}

static int __vlan_vid_add(struct vlan_info *vlan_info, unsigned short vid,
			  struct vlan_vid_info **pvid_info)
{
	struct net_device *dev = vlan_info->real_dev;
	const struct net_device_ops *ops = dev->netdev_ops;
	struct vlan_vid_info *vid_info;
	int err;

	vid_info = vlan_vid_info_alloc(vid);
	if (!vid_info)
		return -ENOMEM;

	if ((dev->features & NETIF_F_HW_VLAN_FILTER) &&
	    ops->ndo_vlan_rx_add_vid) {
		err =  ops->ndo_vlan_rx_add_vid(dev, vid);
		if (err) {
			kfree(vid_info);
			return err;
		}
	}
	list_add(&vid_info->list, &vlan_info->vid_list);
	vlan_info->nr_vids++;
	*pvid_info = vid_info;
	return 0;
}

int vlan_vid_add(struct net_device *dev, unsigned short vid)
{
	struct vlan_info *vlan_info;
	struct vlan_vid_info *vid_info;
	bool vlan_info_created = false;
	int err;

	ASSERT_RTNL();

	vlan_info = rtnl_dereference(dev->vlan_info);
	if (!vlan_info) {
		vlan_info = vlan_info_alloc(dev);
		if (!vlan_info)
			return -ENOMEM;
		vlan_info_created = true;
	}
	vid_info = vlan_vid_info_get(vlan_info, vid);
	if (!vid_info) {
		err = __vlan_vid_add(vlan_info, vid, &vid_info);
		if (err)
			goto out_free_vlan_info;
	}
	vid_info->refcount++;

	if (vlan_info_created)
		rcu_assign_pointer(dev->vlan_info, vlan_info);

	return 0;

out_free_vlan_info:
	if (vlan_info_created)
		kfree(vlan_info);
	return err;
}
EXPORT_SYMBOL(vlan_vid_add);

static void __vlan_vid_del(struct vlan_info *vlan_info,
			   struct vlan_vid_info *vid_info)
{
	struct net_device *dev = vlan_info->real_dev;
	const struct net_device_ops *ops = dev->netdev_ops;
	unsigned short vid = vid_info->vid;
	int err;

	if ((dev->features & NETIF_F_HW_VLAN_FILTER) &&
	     ops->ndo_vlan_rx_kill_vid) {
		err = ops->ndo_vlan_rx_kill_vid(dev, vid);
		if (err) {
			pr_warn("failed to kill vid %d for device %s\n",
				vid, dev->name);
		}
	}
	list_del(&vid_info->list);
	kfree(vid_info);
	vlan_info->nr_vids--;
}

void vlan_vid_del(struct net_device *dev, unsigned short vid)
{
	struct vlan_info *vlan_info;
	struct vlan_vid_info *vid_info;

	ASSERT_RTNL();

	vlan_info = rtnl_dereference(dev->vlan_info);
	if (!vlan_info)
		return;

	vid_info = vlan_vid_info_get(vlan_info, vid);
	if (!vid_info)
		return;
	vid_info->refcount--;
	if (vid_info->refcount == 0) {
		__vlan_vid_del(vlan_info, vid_info);
		if (vlan_info->nr_vids == 0) {
			RCU_INIT_POINTER(dev->vlan_info, NULL);
			call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
		}
	}
}
EXPORT_SYMBOL(vlan_vid_del);

int vlan_vids_add_by_dev(struct net_device *dev,
			 const struct net_device *by_dev)
{
	struct vlan_vid_info *vid_info;
	struct vlan_info *vlan_info;
	int err;

	ASSERT_RTNL();

	vlan_info = rtnl_dereference(by_dev->vlan_info);
	if (!vlan_info)
		return 0;

	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
		err = vlan_vid_add(dev, vid_info->vid);
		if (err)
			goto unwind;
	}
	return 0;

unwind:
	list_for_each_entry_continue_reverse(vid_info,
					     &vlan_info->vid_list,
					     list) {
		vlan_vid_del(dev, vid_info->vid);
	}

	return err;
}
EXPORT_SYMBOL(vlan_vids_add_by_dev);

void vlan_vids_del_by_dev(struct net_device *dev,
			  const struct net_device *by_dev)
{
	struct vlan_vid_info *vid_info;
	struct vlan_info *vlan_info;

	ASSERT_RTNL();

	vlan_info = rtnl_dereference(by_dev->vlan_info);
	if (!vlan_info)
		return;

	list_for_each_entry(vid_info, &vlan_info->vid_list, list)
		vlan_vid_del(dev, vid_info->vid);
}
EXPORT_SYMBOL(vlan_vids_del_by_dev);

bool vlan_uses_dev(const struct net_device *dev)
{
	return rtnl_dereference(dev->vlan_info) ? true : false;
}
EXPORT_SYMBOL(vlan_uses_dev);