xref: /openbmc/linux/net/8021q/vlan_core.c (revision 5a244f48)
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 
8 bool 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 = skb_vlan_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 	if (unlikely(!(vlan_dev->flags & IFF_UP))) {
25 		kfree_skb(skb);
26 		*skbp = NULL;
27 		return false;
28 	}
29 
30 	skb->dev = vlan_dev;
31 	if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) {
32 		/* Our lower layer thinks this is not local, let's make sure.
33 		 * This allows the VLAN to have a different MAC than the
34 		 * underlying device, and still route correctly. */
35 		if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
36 			skb->pkt_type = PACKET_HOST;
37 	}
38 
39 	if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR) &&
40 	    !netif_is_macvlan_port(vlan_dev) &&
41 	    !netif_is_bridge_port(vlan_dev)) {
42 		unsigned int offset = skb->data - skb_mac_header(skb);
43 
44 		/*
45 		 * vlan_insert_tag expect skb->data pointing to mac header.
46 		 * So change skb->data before calling it and change back to
47 		 * original position later
48 		 */
49 		skb_push(skb, offset);
50 		skb = *skbp = vlan_insert_tag(skb, skb->vlan_proto,
51 					      skb->vlan_tci);
52 		if (!skb)
53 			return false;
54 		skb_pull(skb, offset + VLAN_HLEN);
55 		skb_reset_mac_len(skb);
56 	}
57 
58 	skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
59 	skb->vlan_tci = 0;
60 
61 	rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
62 
63 	u64_stats_update_begin(&rx_stats->syncp);
64 	rx_stats->rx_packets++;
65 	rx_stats->rx_bytes += skb->len;
66 	if (skb->pkt_type == PACKET_MULTICAST)
67 		rx_stats->rx_multicast++;
68 	u64_stats_update_end(&rx_stats->syncp);
69 
70 	return true;
71 }
72 
73 /* Must be invoked with rcu_read_lock. */
74 struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
75 					__be16 vlan_proto, u16 vlan_id)
76 {
77 	struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
78 
79 	if (vlan_info) {
80 		return vlan_group_get_device(&vlan_info->grp,
81 					     vlan_proto, vlan_id);
82 	} else {
83 		/*
84 		 * Lower devices of master uppers (bonding, team) do not have
85 		 * grp assigned to themselves. Grp is assigned to upper device
86 		 * instead.
87 		 */
88 		struct net_device *upper_dev;
89 
90 		upper_dev = netdev_master_upper_dev_get_rcu(dev);
91 		if (upper_dev)
92 			return __vlan_find_dev_deep_rcu(upper_dev,
93 						    vlan_proto, vlan_id);
94 	}
95 
96 	return NULL;
97 }
98 EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
99 
100 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
101 {
102 	struct net_device *ret = vlan_dev_priv(dev)->real_dev;
103 
104 	while (is_vlan_dev(ret))
105 		ret = vlan_dev_priv(ret)->real_dev;
106 
107 	return ret;
108 }
109 EXPORT_SYMBOL(vlan_dev_real_dev);
110 
111 u16 vlan_dev_vlan_id(const struct net_device *dev)
112 {
113 	return vlan_dev_priv(dev)->vlan_id;
114 }
115 EXPORT_SYMBOL(vlan_dev_vlan_id);
116 
117 __be16 vlan_dev_vlan_proto(const struct net_device *dev)
118 {
119 	return vlan_dev_priv(dev)->vlan_proto;
120 }
121 EXPORT_SYMBOL(vlan_dev_vlan_proto);
122 
123 /*
124  * vlan info and vid list
125  */
126 
127 static void vlan_group_free(struct vlan_group *grp)
128 {
129 	int i, j;
130 
131 	for (i = 0; i < VLAN_PROTO_NUM; i++)
132 		for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
133 			kfree(grp->vlan_devices_arrays[i][j]);
134 }
135 
136 static void vlan_info_free(struct vlan_info *vlan_info)
137 {
138 	vlan_group_free(&vlan_info->grp);
139 	kfree(vlan_info);
140 }
141 
142 static void vlan_info_rcu_free(struct rcu_head *rcu)
143 {
144 	vlan_info_free(container_of(rcu, struct vlan_info, rcu));
145 }
146 
147 static struct vlan_info *vlan_info_alloc(struct net_device *dev)
148 {
149 	struct vlan_info *vlan_info;
150 
151 	vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
152 	if (!vlan_info)
153 		return NULL;
154 
155 	vlan_info->real_dev = dev;
156 	INIT_LIST_HEAD(&vlan_info->vid_list);
157 	return vlan_info;
158 }
159 
160 struct vlan_vid_info {
161 	struct list_head list;
162 	__be16 proto;
163 	u16 vid;
164 	int refcount;
165 };
166 
167 static bool vlan_hw_filter_capable(const struct net_device *dev,
168 				     const struct vlan_vid_info *vid_info)
169 {
170 	if (vid_info->proto == htons(ETH_P_8021Q) &&
171 	    dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
172 		return true;
173 	if (vid_info->proto == htons(ETH_P_8021AD) &&
174 	    dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
175 		return true;
176 	return false;
177 }
178 
179 static 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 
191 static 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 
204 static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
205 			  struct vlan_vid_info **pvid_info)
206 {
207 	struct net_device *dev = vlan_info->real_dev;
208 	const struct net_device_ops *ops = dev->netdev_ops;
209 	struct vlan_vid_info *vid_info;
210 	int err;
211 
212 	vid_info = vlan_vid_info_alloc(proto, vid);
213 	if (!vid_info)
214 		return -ENOMEM;
215 
216 	if (vlan_hw_filter_capable(dev, vid_info)) {
217 		if (netif_device_present(dev))
218 			err = ops->ndo_vlan_rx_add_vid(dev, proto, vid);
219 		else
220 			err = -ENODEV;
221 		if (err) {
222 			kfree(vid_info);
223 			return err;
224 		}
225 	}
226 	list_add(&vid_info->list, &vlan_info->vid_list);
227 	vlan_info->nr_vids++;
228 	*pvid_info = vid_info;
229 	return 0;
230 }
231 
232 int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
233 {
234 	struct vlan_info *vlan_info;
235 	struct vlan_vid_info *vid_info;
236 	bool vlan_info_created = false;
237 	int err;
238 
239 	ASSERT_RTNL();
240 
241 	vlan_info = rtnl_dereference(dev->vlan_info);
242 	if (!vlan_info) {
243 		vlan_info = vlan_info_alloc(dev);
244 		if (!vlan_info)
245 			return -ENOMEM;
246 		vlan_info_created = true;
247 	}
248 	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
249 	if (!vid_info) {
250 		err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
251 		if (err)
252 			goto out_free_vlan_info;
253 	}
254 	vid_info->refcount++;
255 
256 	if (vlan_info_created)
257 		rcu_assign_pointer(dev->vlan_info, vlan_info);
258 
259 	return 0;
260 
261 out_free_vlan_info:
262 	if (vlan_info_created)
263 		kfree(vlan_info);
264 	return err;
265 }
266 EXPORT_SYMBOL(vlan_vid_add);
267 
268 static void __vlan_vid_del(struct vlan_info *vlan_info,
269 			   struct vlan_vid_info *vid_info)
270 {
271 	struct net_device *dev = vlan_info->real_dev;
272 	const struct net_device_ops *ops = dev->netdev_ops;
273 	__be16 proto = vid_info->proto;
274 	u16 vid = vid_info->vid;
275 	int err;
276 
277 	if (vlan_hw_filter_capable(dev, vid_info)) {
278 		if (netif_device_present(dev))
279 			err = ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
280 		else
281 			err = -ENODEV;
282 		if (err) {
283 			pr_warn("failed to kill vid %04x/%d for device %s\n",
284 				proto, vid, dev->name);
285 		}
286 	}
287 	list_del(&vid_info->list);
288 	kfree(vid_info);
289 	vlan_info->nr_vids--;
290 }
291 
292 void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
293 {
294 	struct vlan_info *vlan_info;
295 	struct vlan_vid_info *vid_info;
296 
297 	ASSERT_RTNL();
298 
299 	vlan_info = rtnl_dereference(dev->vlan_info);
300 	if (!vlan_info)
301 		return;
302 
303 	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
304 	if (!vid_info)
305 		return;
306 	vid_info->refcount--;
307 	if (vid_info->refcount == 0) {
308 		__vlan_vid_del(vlan_info, vid_info);
309 		if (vlan_info->nr_vids == 0) {
310 			RCU_INIT_POINTER(dev->vlan_info, NULL);
311 			call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
312 		}
313 	}
314 }
315 EXPORT_SYMBOL(vlan_vid_del);
316 
317 int vlan_vids_add_by_dev(struct net_device *dev,
318 			 const struct net_device *by_dev)
319 {
320 	struct vlan_vid_info *vid_info;
321 	struct vlan_info *vlan_info;
322 	int err;
323 
324 	ASSERT_RTNL();
325 
326 	vlan_info = rtnl_dereference(by_dev->vlan_info);
327 	if (!vlan_info)
328 		return 0;
329 
330 	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
331 		err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
332 		if (err)
333 			goto unwind;
334 	}
335 	return 0;
336 
337 unwind:
338 	list_for_each_entry_continue_reverse(vid_info,
339 					     &vlan_info->vid_list,
340 					     list) {
341 		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
342 	}
343 
344 	return err;
345 }
346 EXPORT_SYMBOL(vlan_vids_add_by_dev);
347 
348 void vlan_vids_del_by_dev(struct net_device *dev,
349 			  const struct net_device *by_dev)
350 {
351 	struct vlan_vid_info *vid_info;
352 	struct vlan_info *vlan_info;
353 
354 	ASSERT_RTNL();
355 
356 	vlan_info = rtnl_dereference(by_dev->vlan_info);
357 	if (!vlan_info)
358 		return;
359 
360 	list_for_each_entry(vid_info, &vlan_info->vid_list, list)
361 		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
362 }
363 EXPORT_SYMBOL(vlan_vids_del_by_dev);
364 
365 bool vlan_uses_dev(const struct net_device *dev)
366 {
367 	struct vlan_info *vlan_info;
368 
369 	ASSERT_RTNL();
370 
371 	vlan_info = rtnl_dereference(dev->vlan_info);
372 	if (!vlan_info)
373 		return false;
374 	return vlan_info->grp.nr_vlan_devs ? true : false;
375 }
376 EXPORT_SYMBOL(vlan_uses_dev);
377