xref: /openbmc/linux/net/8021q/vlan_core.c (revision 4f6cce39)
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 	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 	    !netif_is_macvlan_port(vlan_dev) &&
35 	    !netif_is_bridge_port(vlan_dev)) {
36 		unsigned int offset = skb->data - skb_mac_header(skb);
37 
38 		/*
39 		 * vlan_insert_tag expect skb->data pointing to mac header.
40 		 * So change skb->data before calling it and change back to
41 		 * original position later
42 		 */
43 		skb_push(skb, offset);
44 		skb = *skbp = vlan_insert_tag(skb, skb->vlan_proto,
45 					      skb->vlan_tci);
46 		if (!skb)
47 			return false;
48 		skb_pull(skb, offset + VLAN_HLEN);
49 		skb_reset_mac_len(skb);
50 	}
51 
52 	skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
53 	skb->vlan_tci = 0;
54 
55 	rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
56 
57 	u64_stats_update_begin(&rx_stats->syncp);
58 	rx_stats->rx_packets++;
59 	rx_stats->rx_bytes += skb->len;
60 	if (skb->pkt_type == PACKET_MULTICAST)
61 		rx_stats->rx_multicast++;
62 	u64_stats_update_end(&rx_stats->syncp);
63 
64 	return true;
65 }
66 
67 /* Must be invoked with rcu_read_lock. */
68 struct net_device *__vlan_find_dev_deep_rcu(struct net_device *dev,
69 					__be16 vlan_proto, u16 vlan_id)
70 {
71 	struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
72 
73 	if (vlan_info) {
74 		return vlan_group_get_device(&vlan_info->grp,
75 					     vlan_proto, vlan_id);
76 	} else {
77 		/*
78 		 * Lower devices of master uppers (bonding, team) do not have
79 		 * grp assigned to themselves. Grp is assigned to upper device
80 		 * instead.
81 		 */
82 		struct net_device *upper_dev;
83 
84 		upper_dev = netdev_master_upper_dev_get_rcu(dev);
85 		if (upper_dev)
86 			return __vlan_find_dev_deep_rcu(upper_dev,
87 						    vlan_proto, vlan_id);
88 	}
89 
90 	return NULL;
91 }
92 EXPORT_SYMBOL(__vlan_find_dev_deep_rcu);
93 
94 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
95 {
96 	struct net_device *ret = vlan_dev_priv(dev)->real_dev;
97 
98 	while (is_vlan_dev(ret))
99 		ret = vlan_dev_priv(ret)->real_dev;
100 
101 	return ret;
102 }
103 EXPORT_SYMBOL(vlan_dev_real_dev);
104 
105 u16 vlan_dev_vlan_id(const struct net_device *dev)
106 {
107 	return vlan_dev_priv(dev)->vlan_id;
108 }
109 EXPORT_SYMBOL(vlan_dev_vlan_id);
110 
111 __be16 vlan_dev_vlan_proto(const struct net_device *dev)
112 {
113 	return vlan_dev_priv(dev)->vlan_proto;
114 }
115 EXPORT_SYMBOL(vlan_dev_vlan_proto);
116 
117 /*
118  * vlan info and vid list
119  */
120 
121 static void vlan_group_free(struct vlan_group *grp)
122 {
123 	int i, j;
124 
125 	for (i = 0; i < VLAN_PROTO_NUM; i++)
126 		for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
127 			kfree(grp->vlan_devices_arrays[i][j]);
128 }
129 
130 static void vlan_info_free(struct vlan_info *vlan_info)
131 {
132 	vlan_group_free(&vlan_info->grp);
133 	kfree(vlan_info);
134 }
135 
136 static void vlan_info_rcu_free(struct rcu_head *rcu)
137 {
138 	vlan_info_free(container_of(rcu, struct vlan_info, rcu));
139 }
140 
141 static struct vlan_info *vlan_info_alloc(struct net_device *dev)
142 {
143 	struct vlan_info *vlan_info;
144 
145 	vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
146 	if (!vlan_info)
147 		return NULL;
148 
149 	vlan_info->real_dev = dev;
150 	INIT_LIST_HEAD(&vlan_info->vid_list);
151 	return vlan_info;
152 }
153 
154 struct vlan_vid_info {
155 	struct list_head list;
156 	__be16 proto;
157 	u16 vid;
158 	int refcount;
159 };
160 
161 static bool vlan_hw_filter_capable(const struct net_device *dev,
162 				     const struct vlan_vid_info *vid_info)
163 {
164 	if (vid_info->proto == htons(ETH_P_8021Q) &&
165 	    dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
166 		return true;
167 	if (vid_info->proto == htons(ETH_P_8021AD) &&
168 	    dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
169 		return true;
170 	return false;
171 }
172 
173 static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
174 					       __be16 proto, u16 vid)
175 {
176 	struct vlan_vid_info *vid_info;
177 
178 	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
179 		if (vid_info->proto == proto && vid_info->vid == vid)
180 			return vid_info;
181 	}
182 	return NULL;
183 }
184 
185 static struct vlan_vid_info *vlan_vid_info_alloc(__be16 proto, u16 vid)
186 {
187 	struct vlan_vid_info *vid_info;
188 
189 	vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
190 	if (!vid_info)
191 		return NULL;
192 	vid_info->proto = proto;
193 	vid_info->vid = vid;
194 
195 	return vid_info;
196 }
197 
198 static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
199 			  struct vlan_vid_info **pvid_info)
200 {
201 	struct net_device *dev = vlan_info->real_dev;
202 	const struct net_device_ops *ops = dev->netdev_ops;
203 	struct vlan_vid_info *vid_info;
204 	int err;
205 
206 	vid_info = vlan_vid_info_alloc(proto, vid);
207 	if (!vid_info)
208 		return -ENOMEM;
209 
210 	if (vlan_hw_filter_capable(dev, vid_info)) {
211 		if (netif_device_present(dev))
212 			err = ops->ndo_vlan_rx_add_vid(dev, proto, vid);
213 		else
214 			err = -ENODEV;
215 		if (err) {
216 			kfree(vid_info);
217 			return err;
218 		}
219 	}
220 	list_add(&vid_info->list, &vlan_info->vid_list);
221 	vlan_info->nr_vids++;
222 	*pvid_info = vid_info;
223 	return 0;
224 }
225 
226 int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
227 {
228 	struct vlan_info *vlan_info;
229 	struct vlan_vid_info *vid_info;
230 	bool vlan_info_created = false;
231 	int err;
232 
233 	ASSERT_RTNL();
234 
235 	vlan_info = rtnl_dereference(dev->vlan_info);
236 	if (!vlan_info) {
237 		vlan_info = vlan_info_alloc(dev);
238 		if (!vlan_info)
239 			return -ENOMEM;
240 		vlan_info_created = true;
241 	}
242 	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
243 	if (!vid_info) {
244 		err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
245 		if (err)
246 			goto out_free_vlan_info;
247 	}
248 	vid_info->refcount++;
249 
250 	if (vlan_info_created)
251 		rcu_assign_pointer(dev->vlan_info, vlan_info);
252 
253 	return 0;
254 
255 out_free_vlan_info:
256 	if (vlan_info_created)
257 		kfree(vlan_info);
258 	return err;
259 }
260 EXPORT_SYMBOL(vlan_vid_add);
261 
262 static void __vlan_vid_del(struct vlan_info *vlan_info,
263 			   struct vlan_vid_info *vid_info)
264 {
265 	struct net_device *dev = vlan_info->real_dev;
266 	const struct net_device_ops *ops = dev->netdev_ops;
267 	__be16 proto = vid_info->proto;
268 	u16 vid = vid_info->vid;
269 	int err;
270 
271 	if (vlan_hw_filter_capable(dev, vid_info)) {
272 		if (netif_device_present(dev))
273 			err = ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
274 		else
275 			err = -ENODEV;
276 		if (err) {
277 			pr_warn("failed to kill vid %04x/%d for device %s\n",
278 				proto, vid, dev->name);
279 		}
280 	}
281 	list_del(&vid_info->list);
282 	kfree(vid_info);
283 	vlan_info->nr_vids--;
284 }
285 
286 void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
287 {
288 	struct vlan_info *vlan_info;
289 	struct vlan_vid_info *vid_info;
290 
291 	ASSERT_RTNL();
292 
293 	vlan_info = rtnl_dereference(dev->vlan_info);
294 	if (!vlan_info)
295 		return;
296 
297 	vid_info = vlan_vid_info_get(vlan_info, proto, vid);
298 	if (!vid_info)
299 		return;
300 	vid_info->refcount--;
301 	if (vid_info->refcount == 0) {
302 		__vlan_vid_del(vlan_info, vid_info);
303 		if (vlan_info->nr_vids == 0) {
304 			RCU_INIT_POINTER(dev->vlan_info, NULL);
305 			call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
306 		}
307 	}
308 }
309 EXPORT_SYMBOL(vlan_vid_del);
310 
311 int vlan_vids_add_by_dev(struct net_device *dev,
312 			 const struct net_device *by_dev)
313 {
314 	struct vlan_vid_info *vid_info;
315 	struct vlan_info *vlan_info;
316 	int err;
317 
318 	ASSERT_RTNL();
319 
320 	vlan_info = rtnl_dereference(by_dev->vlan_info);
321 	if (!vlan_info)
322 		return 0;
323 
324 	list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
325 		err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
326 		if (err)
327 			goto unwind;
328 	}
329 	return 0;
330 
331 unwind:
332 	list_for_each_entry_continue_reverse(vid_info,
333 					     &vlan_info->vid_list,
334 					     list) {
335 		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
336 	}
337 
338 	return err;
339 }
340 EXPORT_SYMBOL(vlan_vids_add_by_dev);
341 
342 void vlan_vids_del_by_dev(struct net_device *dev,
343 			  const struct net_device *by_dev)
344 {
345 	struct vlan_vid_info *vid_info;
346 	struct vlan_info *vlan_info;
347 
348 	ASSERT_RTNL();
349 
350 	vlan_info = rtnl_dereference(by_dev->vlan_info);
351 	if (!vlan_info)
352 		return;
353 
354 	list_for_each_entry(vid_info, &vlan_info->vid_list, list)
355 		vlan_vid_del(dev, vid_info->proto, vid_info->vid);
356 }
357 EXPORT_SYMBOL(vlan_vids_del_by_dev);
358 
359 bool vlan_uses_dev(const struct net_device *dev)
360 {
361 	struct vlan_info *vlan_info;
362 
363 	ASSERT_RTNL();
364 
365 	vlan_info = rtnl_dereference(dev->vlan_info);
366 	if (!vlan_info)
367 		return false;
368 	return vlan_info->grp.nr_vlan_devs ? true : false;
369 }
370 EXPORT_SYMBOL(vlan_uses_dev);
371