xref: /kernel/linux/linux-5.10/net/8021q/vlan_core.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/skbuff.h>
3#include <linux/netdevice.h>
4#include <linux/if_vlan.h>
5#include <linux/netpoll.h>
6#include <linux/export.h>
7#include "vlan.h"
8
9bool vlan_do_receive(struct sk_buff **skbp)
10{
11	struct sk_buff *skb = *skbp;
12	__be16 vlan_proto = skb->vlan_proto;
13	u16 vlan_id = skb_vlan_tag_get_id(skb);
14	struct net_device *vlan_dev;
15	struct vlan_pcpu_stats *rx_stats;
16
17	vlan_dev = vlan_find_dev(skb->dev, vlan_proto, vlan_id);
18	if (!vlan_dev)
19		return false;
20
21	skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
22	if (unlikely(!skb))
23		return false;
24
25	if (unlikely(!(vlan_dev->flags & IFF_UP))) {
26		kfree_skb(skb);
27		*skbp = NULL;
28		return false;
29	}
30
31	skb->dev = vlan_dev;
32	if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) {
33		/* Our lower layer thinks this is not local, let's make sure.
34		 * This allows the VLAN to have a different MAC than the
35		 * underlying device, and still route correctly. */
36		if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
37			skb->pkt_type = PACKET_HOST;
38	}
39
40	if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR) &&
41	    !netif_is_macvlan_port(vlan_dev) &&
42	    !netif_is_bridge_port(vlan_dev)) {
43		unsigned int offset = skb->data - skb_mac_header(skb);
44
45		/*
46		 * vlan_insert_tag expect skb->data pointing to mac header.
47		 * So change skb->data before calling it and change back to
48		 * original position later
49		 */
50		skb_push(skb, offset);
51		skb = *skbp = vlan_insert_inner_tag(skb, skb->vlan_proto,
52						    skb->vlan_tci, skb->mac_len);
53		if (!skb)
54			return false;
55		skb_pull(skb, offset + VLAN_HLEN);
56		skb_reset_mac_len(skb);
57	}
58
59	skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
60	__vlan_hwaccel_clear_tag(skb);
61
62	rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
63
64	u64_stats_update_begin(&rx_stats->syncp);
65	rx_stats->rx_packets++;
66	rx_stats->rx_bytes += skb->len;
67	if (skb->pkt_type == PACKET_MULTICAST)
68		rx_stats->rx_multicast++;
69	u64_stats_update_end(&rx_stats->syncp);
70
71	return true;
72}
73
74/* Must be invoked with rcu_read_lock. */
75struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
76					__be16 vlan_proto, u16 vlan_id)
77{
78	struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
79
80	if (vlan_info) {
81		return vlan_group_get_device(&vlan_info->grp,
82					     vlan_proto, vlan_id);
83	} else {
84		/*
85		 * Lower devices of master uppers (bonding, team) do not have
86		 * grp assigned to themselves. Grp is assigned to upper device
87		 * instead.
88		 */
89		struct net_device *upper_dev;
90
91		upper_dev = netdev_master_upper_dev_get_rcu(dev);
92		if (upper_dev)
93			return __vlan_find_dev_deep_rcu(upper_dev,
94						    vlan_proto, vlan_id);
95	}
96
97	return NULL;
98}
99EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
100
101struct net_device *vlan_dev_real_dev(const struct net_device *dev)
102{
103	struct net_device *ret = vlan_dev_priv(dev)->real_dev;
104
105	while (is_vlan_dev(ret))
106		ret = vlan_dev_priv(ret)->real_dev;
107
108	return ret;
109}
110EXPORT_SYMBOL(vlan_dev_real_dev);
111
112u16 vlan_dev_vlan_id(const struct net_device *dev)
113{
114	return vlan_dev_priv(dev)->vlan_id;
115}
116EXPORT_SYMBOL(vlan_dev_vlan_id);
117
118__be16 vlan_dev_vlan_proto(const struct net_device *dev)
119{
120	return vlan_dev_priv(dev)->vlan_proto;
121}
122EXPORT_SYMBOL(vlan_dev_vlan_proto);
123
124/*
125 * vlan info and vid list
126 */
127
128static void vlan_group_free(struct vlan_group *grp)
129{
130	int i, j;
131
132	for (i = 0; i < VLAN_PROTO_NUM; i++)
133		for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
134			kfree(grp->vlan_devices_arrays[i][j]);
135}
136
137static void vlan_info_free(struct vlan_info *vlan_info)
138{
139	vlan_group_free(&vlan_info->grp);
140	kfree(vlan_info);
141}
142
143static void vlan_info_rcu_free(struct rcu_head *rcu)
144{
145	vlan_info_free(container_of(rcu, struct vlan_info, rcu));
146}
147
148static struct vlan_info *vlan_info_alloc(struct net_device *dev)
149{
150	struct vlan_info *vlan_info;
151
152	vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
153	if (!vlan_info)
154		return NULL;
155
156	vlan_info->real_dev = dev;
157	INIT_LIST_HEAD(&vlan_info->vid_list);
158	return vlan_info;
159}
160
161struct vlan_vid_info {
162	struct list_head list;
163	__be16 proto;
164	u16 vid;
165	int refcount;
166};
167
168static bool vlan_hw_filter_capable(const struct net_device *dev, __be16 proto)
169{
170	if (proto == htons(ETH_P_8021Q) &&
171	    dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
172		return true;
173	if (proto == htons(ETH_P_8021AD) &&
174	    dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
175		return true;
176	return false;
177}
178
179static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
180					       __be16 proto, u16 vid)
181{
182	struct vlan_vid_info *vid_info;
183
184	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
185		if (vid_info->proto == proto && vid_info->vid == vid)
186			return vid_info;
187	}
188	return NULL;
189}
190
191static struct vlan_vid_info *vlan_vid_info_alloc(__be16 proto, u16 vid)
192{
193	struct vlan_vid_info *vid_info;
194
195	vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
196	if (!vid_info)
197		return NULL;
198	vid_info->proto = proto;
199	vid_info->vid = vid;
200
201	return vid_info;
202}
203
204static int vlan_add_rx_filter_info(struct net_device *dev, __be16 proto, u16 vid)
205{
206	if (!vlan_hw_filter_capable(dev, proto))
207		return 0;
208
209	if (netif_device_present(dev))
210		return dev->netdev_ops->ndo_vlan_rx_add_vid(dev, proto, vid);
211	else
212		return -ENODEV;
213}
214
215static int vlan_kill_rx_filter_info(struct net_device *dev, __be16 proto, u16 vid)
216{
217	if (!vlan_hw_filter_capable(dev, proto))
218		return 0;
219
220	if (netif_device_present(dev))
221		return dev->netdev_ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
222	else
223		return -ENODEV;
224}
225
226int vlan_for_each(struct net_device *dev,
227		  int (*action)(struct net_device *dev, int vid, void *arg),
228		  void *arg)
229{
230	struct vlan_vid_info *vid_info;
231	struct vlan_info *vlan_info;
232	struct net_device *vdev;
233	int ret;
234
235	ASSERT_RTNL();
236
237	vlan_info = rtnl_dereference(dev->vlan_info);
238	if (!vlan_info)
239		return 0;
240
241	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
242		vdev = vlan_group_get_device(&vlan_info->grp, vid_info->proto,
243					     vid_info->vid);
244		ret = action(vdev, vid_info->vid, arg);
245		if (ret)
246			return ret;
247	}
248
249	return 0;
250}
251EXPORT_SYMBOL(vlan_for_each);
252
253int vlan_filter_push_vids(struct vlan_info *vlan_info, __be16 proto)
254{
255	struct net_device *real_dev = vlan_info->real_dev;
256	struct vlan_vid_info *vlan_vid_info;
257	int err;
258
259	list_for_each_entry(vlan_vid_info, &vlan_info->vid_list, list) {
260		if (vlan_vid_info->proto == proto) {
261			err = vlan_add_rx_filter_info(real_dev, proto,
262						      vlan_vid_info->vid);
263			if (err)
264				goto unwind;
265		}
266	}
267
268	return 0;
269
270unwind:
271	list_for_each_entry_continue_reverse(vlan_vid_info,
272					     &vlan_info->vid_list, list) {
273		if (vlan_vid_info->proto == proto)
274			vlan_kill_rx_filter_info(real_dev, proto,
275						 vlan_vid_info->vid);
276	}
277
278	return err;
279}
280EXPORT_SYMBOL(vlan_filter_push_vids);
281
282void vlan_filter_drop_vids(struct vlan_info *vlan_info, __be16 proto)
283{
284	struct vlan_vid_info *vlan_vid_info;
285
286	list_for_each_entry(vlan_vid_info, &vlan_info->vid_list, list)
287		if (vlan_vid_info->proto == proto)
288			vlan_kill_rx_filter_info(vlan_info->real_dev,
289						 vlan_vid_info->proto,
290						 vlan_vid_info->vid);
291}
292EXPORT_SYMBOL(vlan_filter_drop_vids);
293
294static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
295			  struct vlan_vid_info **pvid_info)
296{
297	struct net_device *dev = vlan_info->real_dev;
298	struct vlan_vid_info *vid_info;
299	int err;
300
301	vid_info = vlan_vid_info_alloc(proto, vid);
302	if (!vid_info)
303		return -ENOMEM;
304
305	err = vlan_add_rx_filter_info(dev, proto, vid);
306	if (err) {
307		kfree(vid_info);
308		return err;
309	}
310
311	list_add(&vid_info->list, &vlan_info->vid_list);
312	vlan_info->nr_vids++;
313	*pvid_info = vid_info;
314	return 0;
315}
316
317int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
318{
319	struct vlan_info *vlan_info;
320	struct vlan_vid_info *vid_info;
321	bool vlan_info_created = false;
322	int err;
323
324	ASSERT_RTNL();
325
326	vlan_info = rtnl_dereference(dev->vlan_info);
327	if (!vlan_info) {
328		vlan_info = vlan_info_alloc(dev);
329		if (!vlan_info)
330			return -ENOMEM;
331		vlan_info_created = true;
332	}
333	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
334	if (!vid_info) {
335		err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
336		if (err)
337			goto out_free_vlan_info;
338	}
339	vid_info->refcount++;
340
341	if (vlan_info_created)
342		rcu_assign_pointer(dev->vlan_info, vlan_info);
343
344	return 0;
345
346out_free_vlan_info:
347	if (vlan_info_created)
348		kfree(vlan_info);
349	return err;
350}
351EXPORT_SYMBOL(vlan_vid_add);
352
353static void __vlan_vid_del(struct vlan_info *vlan_info,
354			   struct vlan_vid_info *vid_info)
355{
356	struct net_device *dev = vlan_info->real_dev;
357	__be16 proto = vid_info->proto;
358	u16 vid = vid_info->vid;
359	int err;
360
361	err = vlan_kill_rx_filter_info(dev, proto, vid);
362	if (err && dev->reg_state != NETREG_UNREGISTERING)
363		netdev_warn(dev, "failed to kill vid %04x/%d\n", proto, vid);
364
365	list_del(&vid_info->list);
366	kfree(vid_info);
367	vlan_info->nr_vids--;
368}
369
370void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
371{
372	struct vlan_info *vlan_info;
373	struct vlan_vid_info *vid_info;
374
375	ASSERT_RTNL();
376
377	vlan_info = rtnl_dereference(dev->vlan_info);
378	if (!vlan_info)
379		return;
380
381	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
382	if (!vid_info)
383		return;
384	vid_info->refcount--;
385	if (vid_info->refcount == 0) {
386		__vlan_vid_del(vlan_info, vid_info);
387		if (vlan_info->nr_vids == 0) {
388			RCU_INIT_POINTER(dev->vlan_info, NULL);
389			call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
390		}
391	}
392}
393EXPORT_SYMBOL(vlan_vid_del);
394
395int vlan_vids_add_by_dev(struct net_device *dev,
396			 const struct net_device *by_dev)
397{
398	struct vlan_vid_info *vid_info;
399	struct vlan_info *vlan_info;
400	int err;
401
402	ASSERT_RTNL();
403
404	vlan_info = rtnl_dereference(by_dev->vlan_info);
405	if (!vlan_info)
406		return 0;
407
408	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
409		if (!vlan_hw_filter_capable(by_dev, vid_info->proto))
410			continue;
411		err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
412		if (err)
413			goto unwind;
414	}
415	return 0;
416
417unwind:
418	list_for_each_entry_continue_reverse(vid_info,
419					     &vlan_info->vid_list,
420					     list) {
421		if (!vlan_hw_filter_capable(by_dev, vid_info->proto))
422			continue;
423		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
424	}
425
426	return err;
427}
428EXPORT_SYMBOL(vlan_vids_add_by_dev);
429
430void vlan_vids_del_by_dev(struct net_device *dev,
431			  const struct net_device *by_dev)
432{
433	struct vlan_vid_info *vid_info;
434	struct vlan_info *vlan_info;
435
436	ASSERT_RTNL();
437
438	vlan_info = rtnl_dereference(by_dev->vlan_info);
439	if (!vlan_info)
440		return;
441
442	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
443		if (!vlan_hw_filter_capable(by_dev, vid_info->proto))
444			continue;
445		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
446	}
447}
448EXPORT_SYMBOL(vlan_vids_del_by_dev);
449
450bool vlan_uses_dev(const struct net_device *dev)
451{
452	struct vlan_info *vlan_info;
453
454	ASSERT_RTNL();
455
456	vlan_info = rtnl_dereference(dev->vlan_info);
457	if (!vlan_info)
458		return false;
459	return vlan_info->grp.nr_vlan_devs ? true : false;
460}
461EXPORT_SYMBOL(vlan_uses_dev);
462
463static struct sk_buff *vlan_gro_receive(struct list_head *head,
464					struct sk_buff *skb)
465{
466	const struct packet_offload *ptype;
467	unsigned int hlen, off_vlan;
468	struct sk_buff *pp = NULL;
469	struct vlan_hdr *vhdr;
470	struct sk_buff *p;
471	__be16 type;
472	int flush = 1;
473
474	off_vlan = skb_gro_offset(skb);
475	hlen = off_vlan + sizeof(*vhdr);
476	vhdr = skb_gro_header_fast(skb, off_vlan);
477	if (skb_gro_header_hard(skb, hlen)) {
478		vhdr = skb_gro_header_slow(skb, hlen, off_vlan);
479		if (unlikely(!vhdr))
480			goto out;
481	}
482
483	type = vhdr->h_vlan_encapsulated_proto;
484
485	rcu_read_lock();
486	ptype = gro_find_receive_by_type(type);
487	if (!ptype)
488		goto out_unlock;
489
490	flush = 0;
491
492	list_for_each_entry(p, head, list) {
493		struct vlan_hdr *vhdr2;
494
495		if (!NAPI_GRO_CB(p)->same_flow)
496			continue;
497
498		vhdr2 = (struct vlan_hdr *)(p->data + off_vlan);
499		if (compare_vlan_header(vhdr, vhdr2))
500			NAPI_GRO_CB(p)->same_flow = 0;
501	}
502
503	skb_gro_pull(skb, sizeof(*vhdr));
504	skb_gro_postpull_rcsum(skb, vhdr, sizeof(*vhdr));
505	pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb);
506
507out_unlock:
508	rcu_read_unlock();
509out:
510	skb_gro_flush_final(skb, pp, flush);
511
512	return pp;
513}
514
515static int vlan_gro_complete(struct sk_buff *skb, int nhoff)
516{
517	struct vlan_hdr *vhdr = (struct vlan_hdr *)(skb->data + nhoff);
518	__be16 type = vhdr->h_vlan_encapsulated_proto;
519	struct packet_offload *ptype;
520	int err = -ENOENT;
521
522	rcu_read_lock();
523	ptype = gro_find_complete_by_type(type);
524	if (ptype)
525		err = ptype->callbacks.gro_complete(skb, nhoff + sizeof(*vhdr));
526
527	rcu_read_unlock();
528	return err;
529}
530
531static struct packet_offload vlan_packet_offloads[] __read_mostly = {
532	{
533		.type = cpu_to_be16(ETH_P_8021Q),
534		.priority = 10,
535		.callbacks = {
536			.gro_receive = vlan_gro_receive,
537			.gro_complete = vlan_gro_complete,
538		},
539	},
540	{
541		.type = cpu_to_be16(ETH_P_8021AD),
542		.priority = 10,
543		.callbacks = {
544			.gro_receive = vlan_gro_receive,
545			.gro_complete = vlan_gro_complete,
546		},
547	},
548};
549
550static int __init vlan_offload_init(void)
551{
552	unsigned int i;
553
554	for (i = 0; i < ARRAY_SIZE(vlan_packet_offloads); i++)
555		dev_add_offload(&vlan_packet_offloads[i]);
556
557	return 0;
558}
559
560fs_initcall(vlan_offload_init);
561