summaryrefslogtreecommitdiff
path: root/net/bridge/br_vlan.c
blob: af5ebd18d7059f2d0cc289e226c544f210309dc2 (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
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>

#include "br_private.h"

static void __vlan_add_pvid(struct net_port_vlans *v, u16 vid)
{
	if (v->pvid == vid)
		return;

	smp_wmb();
	v->pvid = vid;
}

static void __vlan_delete_pvid(struct net_port_vlans *v, u16 vid)
{
	if (v->pvid != vid)
		return;

	smp_wmb();
	v->pvid = 0;
}

static void __vlan_add_flags(struct net_port_vlans *v, u16 vid, u16 flags)
{
	if (flags & BRIDGE_VLAN_INFO_PVID)
		__vlan_add_pvid(v, vid);

	if (flags & BRIDGE_VLAN_INFO_UNTAGGED)
		set_bit(vid, v->untagged_bitmap);
}

static int __vlan_add(struct net_port_vlans *v, u16 vid, u16 flags)
{
	struct net_bridge_port *p = NULL;
	struct net_bridge *br;
	struct net_device *dev;
	int err;

	if (test_bit(vid, v->vlan_bitmap)) {
		__vlan_add_flags(v, vid, flags);
		return 0;
	}

	if (v->port_idx) {
		p = v->parent.port;
		br = p->br;
		dev = p->dev;
	} else {
		br = v->parent.br;
		dev = br->dev;
	}

	if (p) {
		/* Add VLAN to the device filter if it is supported.
		 * Stricly speaking, this is not necessary now, since
		 * devices are made promiscuous by the bridge, but if
		 * that ever changes this code will allow tagged
		 * traffic to enter the bridge.
		 */
		err = vlan_vid_add(dev, htons(ETH_P_8021Q), vid);
		if (err)
			return err;
	}

	err = br_fdb_insert(br, p, dev->dev_addr, vid);
	if (err) {
		br_err(br, "failed insert local address into bridge "
		       "forwarding table\n");
		goto out_filt;
	}

	set_bit(vid, v->vlan_bitmap);
	v->num_vlans++;
	__vlan_add_flags(v, vid, flags);

	return 0;

out_filt:
	if (p)
		vlan_vid_del(dev, htons(ETH_P_8021Q), vid);
	return err;
}

static int __vlan_del(struct net_port_vlans *v, u16 vid)
{
	if (!test_bit(vid, v->vlan_bitmap))
		return -EINVAL;

	__vlan_delete_pvid(v, vid);
	clear_bit(vid, v->untagged_bitmap);

	if (v->port_idx)
		vlan_vid_del(v->parent.port->dev, htons(ETH_P_8021Q), vid);

	clear_bit(vid, v->vlan_bitmap);
	v->num_vlans--;
	if (bitmap_empty(v->vlan_bitmap, VLAN_N_VID)) {
		if (v->port_idx)
			rcu_assign_pointer(v->parent.port->vlan_info, NULL);
		else
			rcu_assign_pointer(v->parent.br->vlan_info, NULL);
		kfree_rcu(v, rcu);
	}
	return 0;
}

static void __vlan_flush(struct net_port_vlans *v)
{
	smp_wmb();
	v->pvid = 0;
	bitmap_zero(v->vlan_bitmap, VLAN_N_VID);
	if (v->port_idx)
		rcu_assign_pointer(v->parent.port->vlan_info, NULL);
	else
		rcu_assign_pointer(v->parent.br->vlan_info, NULL);
	kfree_rcu(v, rcu);
}

/* Strip the tag from the packet.  Will return skb with tci set 0.  */
static struct sk_buff *br_vlan_untag(struct sk_buff *skb)
{
	if (skb->protocol != htons(ETH_P_8021Q)) {
		skb->vlan_tci = 0;
		return skb;
	}

	skb->vlan_tci = 0;
	skb = vlan_untag(skb);
	if (skb)
		skb->vlan_tci = 0;

	return skb;
}

struct sk_buff *br_handle_vlan(struct net_bridge *br,
			       const struct net_port_vlans *pv,
			       struct sk_buff *skb)
{
	u16 vid;

	if (!br->vlan_enabled)
		goto out;

	/* At this point, we know that the frame was filtered and contains
	 * a valid vlan id.  If the vlan id is set in the untagged bitmap,
	 * send untagged; otherwise, send taged.
	 */
	br_vlan_get_tag(skb, &vid);
	if (test_bit(vid, pv->untagged_bitmap))
		skb = br_vlan_untag(skb);
	else {
		/* Egress policy says "send tagged".  If output device
		 * is the  bridge, we need to add the VLAN header
		 * ourselves since we'll be going through the RX path.
		 * Sending to ports puts the frame on the TX path and
		 * we let dev_hard_start_xmit() add the header.
		 */
		if (skb->protocol != htons(ETH_P_8021Q) &&
		    pv->port_idx == 0) {
			/* vlan_put_tag expects skb->data to point to
			 * mac header.
			 */
			skb_push(skb, ETH_HLEN);
			skb = __vlan_put_tag(skb, skb->vlan_proto, skb->vlan_tci);
			if (!skb)
				goto out;
			/* put skb->data back to where it was */
			skb_pull(skb, ETH_HLEN);
			skb->vlan_tci = 0;
		}
	}

out:
	return skb;
}

/* Called under RCU */
bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v,
			struct sk_buff *skb, u16 *vid)
{
	int err;

	/* If VLAN filtering is disabled on the bridge, all packets are
	 * permitted.
	 */
	if (!br->vlan_enabled)
		return true;

	/* If there are no vlan in the permitted list, all packets are
	 * rejected.
	 */
	if (!v)
		return false;

	err = br_vlan_get_tag(skb, vid);
	if (!*vid) {
		u16 pvid = br_get_pvid(v);

		/* Frame had a tag with VID 0 or did not have a tag.
		 * See if pvid is set on this port.  That tells us which
		 * vlan untagged or priority-tagged traffic belongs to.
		 */
		if (pvid == VLAN_N_VID)
			return false;

		/* PVID is set on this port.  Any untagged or priority-tagged
		 * ingress frame is considered to belong to this vlan.
		 */
		*vid = pvid;
		if (likely(err))
			/* Untagged Frame. */
			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), pvid);
		else
			/* Priority-tagged Frame.
			 * At this point, We know that skb->vlan_tci had
			 * VLAN_TAG_PRESENT bit and its VID field was 0x000.
			 * We update only VID field and preserve PCP field.
			 */
			skb->vlan_tci |= pvid;

		return true;
	}

	/* Frame had a valid vlan tag.  See if vlan is allowed */
	if (test_bit(*vid, v->vlan_bitmap))
		return true;

	return false;
}

/* Called under RCU. */
bool br_allowed_egress(struct net_bridge *br,
		       const struct net_port_vlans *v,
		       const struct sk_buff *skb)
{
	u16 vid;

	if (!br->vlan_enabled)
		return true;

	if (!v)
		return false;

	br_vlan_get_tag(skb, &vid);
	if (test_bit(vid, v->vlan_bitmap))
		return true;

	return false;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int br_vlan_add(struct net_bridge *br, u16 vid, u16 flags)
{
	struct net_port_vlans *pv = NULL;
	int err;

	ASSERT_RTNL();

	pv = rtnl_dereference(br->vlan_info);
	if (pv)
		return __vlan_add(pv, vid, flags);

	/* Create port vlan infomration
	 */
	pv = kzalloc(sizeof(*pv), GFP_KERNEL);
	if (!pv)
		return -ENOMEM;

	pv->parent.br = br;
	err = __vlan_add(pv, vid, flags);
	if (err)
		goto out;

	rcu_assign_pointer(br->vlan_info, pv);
	return 0;
out:
	kfree(pv);
	return err;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int br_vlan_delete(struct net_bridge *br, u16 vid)
{
	struct net_port_vlans *pv;

	ASSERT_RTNL();

	pv = rtnl_dereference(br->vlan_info);
	if (!pv)
		return -EINVAL;

	spin_lock_bh(&br->hash_lock);
	fdb_delete_by_addr(br, br->dev->dev_addr, vid);
	spin_unlock_bh(&br->hash_lock);

	__vlan_del(pv, vid);
	return 0;
}

void br_vlan_flush(struct net_bridge *br)
{
	struct net_port_vlans *pv;

	ASSERT_RTNL();
	pv = rtnl_dereference(br->vlan_info);
	if (!pv)
		return;

	__vlan_flush(pv);
}

int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
{
	if (!rtnl_trylock())
		return restart_syscall();

	if (br->vlan_enabled == val)
		goto unlock;

	br->vlan_enabled = val;

unlock:
	rtnl_unlock();
	return 0;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags)
{
	struct net_port_vlans *pv = NULL;
	int err;

	ASSERT_RTNL();

	pv = rtnl_dereference(port->vlan_info);
	if (pv)
		return __vlan_add(pv, vid, flags);

	/* Create port vlan infomration
	 */
	pv = kzalloc(sizeof(*pv), GFP_KERNEL);
	if (!pv) {
		err = -ENOMEM;
		goto clean_up;
	}

	pv->port_idx = port->port_no;
	pv->parent.port = port;
	err = __vlan_add(pv, vid, flags);
	if (err)
		goto clean_up;

	rcu_assign_pointer(port->vlan_info, pv);
	return 0;

clean_up:
	kfree(pv);
	return err;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int nbp_vlan_delete(struct net_bridge_port *port, u16 vid)
{
	struct net_port_vlans *pv;

	ASSERT_RTNL();

	pv = rtnl_dereference(port->vlan_info);
	if (!pv)
		return -EINVAL;

	spin_lock_bh(&port->br->hash_lock);
	fdb_delete_by_addr(port->br, port->dev->dev_addr, vid);
	spin_unlock_bh(&port->br->hash_lock);

	return __vlan_del(pv, vid);
}

void nbp_vlan_flush(struct net_bridge_port *port)
{
	struct net_port_vlans *pv;
	u16 vid;

	ASSERT_RTNL();

	pv = rtnl_dereference(port->vlan_info);
	if (!pv)
		return;

	for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
		vlan_vid_del(port->dev, htons(ETH_P_8021Q), vid);

	__vlan_flush(pv);
}

bool nbp_vlan_find(struct net_bridge_port *port, u16 vid)
{
	struct net_port_vlans *pv;
	bool found = false;

	rcu_read_lock();
	pv = rcu_dereference(port->vlan_info);

	if (!pv)
		goto out;

	if (test_bit(vid, pv->vlan_bitmap))
		found = true;

out:
	rcu_read_unlock();
	return found;
}