xref: /linux/drivers/net/macvlan.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of
7  * the License, or (at your option) any later version.
8  *
9  * The code this is based on carried the following copyright notice:
10  * ---
11  * (C) Copyright 2001-2006
12  * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
13  * Re-worked by Ben Greear <greearb@candelatech.com>
14  * ---
15  */
16 #include <linux/kernel.h>
17 #include <linux/types.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/errno.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 #include <linux/rculist.h>
24 #include <linux/notifier.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/ethtool.h>
28 #include <linux/if_arp.h>
29 #include <linux/if_vlan.h>
30 #include <linux/if_link.h>
31 #include <linux/if_macvlan.h>
32 #include <net/rtnetlink.h>
33 #include <net/xfrm.h>
34 
35 #define MACVLAN_HASH_SIZE	(1 << BITS_PER_BYTE)
36 
37 struct macvlan_port {
38 	struct net_device	*dev;
39 	struct hlist_head	vlan_hash[MACVLAN_HASH_SIZE];
40 	struct list_head	vlans;
41 	struct rcu_head		rcu;
42 	bool 			passthru;
43 	int			count;
44 };
45 
46 static void macvlan_port_destroy(struct net_device *dev);
47 
48 #define macvlan_port_get_rcu(dev) \
49 	((struct macvlan_port *) rcu_dereference(dev->rx_handler_data))
50 #define macvlan_port_get(dev) ((struct macvlan_port *) dev->rx_handler_data)
51 #define macvlan_port_exists(dev) (dev->priv_flags & IFF_MACVLAN_PORT)
52 
53 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
54 					       const unsigned char *addr)
55 {
56 	struct macvlan_dev *vlan;
57 	struct hlist_node *n;
58 
59 	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
60 		if (!compare_ether_addr_64bits(vlan->dev->dev_addr, addr))
61 			return vlan;
62 	}
63 	return NULL;
64 }
65 
66 static void macvlan_hash_add(struct macvlan_dev *vlan)
67 {
68 	struct macvlan_port *port = vlan->port;
69 	const unsigned char *addr = vlan->dev->dev_addr;
70 
71 	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
72 }
73 
74 static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync)
75 {
76 	hlist_del_rcu(&vlan->hlist);
77 	if (sync)
78 		synchronize_rcu();
79 }
80 
81 static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
82 					const unsigned char *addr)
83 {
84 	macvlan_hash_del(vlan, true);
85 	/* Now that we are unhashed it is safe to change the device
86 	 * address without confusing packet delivery.
87 	 */
88 	memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
89 	macvlan_hash_add(vlan);
90 }
91 
92 static int macvlan_addr_busy(const struct macvlan_port *port,
93 				const unsigned char *addr)
94 {
95 	/* Test to see if the specified multicast address is
96 	 * currently in use by the underlying device or
97 	 * another macvlan.
98 	 */
99 	if (!compare_ether_addr_64bits(port->dev->dev_addr, addr))
100 		return 1;
101 
102 	if (macvlan_hash_lookup(port, addr))
103 		return 1;
104 
105 	return 0;
106 }
107 
108 
109 static int macvlan_broadcast_one(struct sk_buff *skb,
110 				 const struct macvlan_dev *vlan,
111 				 const struct ethhdr *eth, bool local)
112 {
113 	struct net_device *dev = vlan->dev;
114 	if (!skb)
115 		return NET_RX_DROP;
116 
117 	if (local)
118 		return vlan->forward(dev, skb);
119 
120 	skb->dev = dev;
121 	if (!compare_ether_addr_64bits(eth->h_dest,
122 				       dev->broadcast))
123 		skb->pkt_type = PACKET_BROADCAST;
124 	else
125 		skb->pkt_type = PACKET_MULTICAST;
126 
127 	return vlan->receive(skb);
128 }
129 
130 static void macvlan_broadcast(struct sk_buff *skb,
131 			      const struct macvlan_port *port,
132 			      struct net_device *src,
133 			      enum macvlan_mode mode)
134 {
135 	const struct ethhdr *eth = eth_hdr(skb);
136 	const struct macvlan_dev *vlan;
137 	struct hlist_node *n;
138 	struct sk_buff *nskb;
139 	unsigned int i;
140 	int err;
141 
142 	if (skb->protocol == htons(ETH_P_PAUSE))
143 		return;
144 
145 	for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
146 		hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
147 			if (vlan->dev == src || !(vlan->mode & mode))
148 				continue;
149 
150 			nskb = skb_clone(skb, GFP_ATOMIC);
151 			err = macvlan_broadcast_one(nskb, vlan, eth,
152 					 mode == MACVLAN_MODE_BRIDGE);
153 			macvlan_count_rx(vlan, skb->len + ETH_HLEN,
154 					 err == NET_RX_SUCCESS, 1);
155 		}
156 	}
157 }
158 
159 /* called under rcu_read_lock() from netif_receive_skb */
160 static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
161 {
162 	struct macvlan_port *port;
163 	struct sk_buff *skb = *pskb;
164 	const struct ethhdr *eth = eth_hdr(skb);
165 	const struct macvlan_dev *vlan;
166 	const struct macvlan_dev *src;
167 	struct net_device *dev;
168 	unsigned int len = 0;
169 	int ret = NET_RX_DROP;
170 
171 	port = macvlan_port_get_rcu(skb->dev);
172 	if (is_multicast_ether_addr(eth->h_dest)) {
173 		skb = ip_check_defrag(skb, IP_DEFRAG_MACVLAN);
174 		if (!skb)
175 			return RX_HANDLER_CONSUMED;
176 		src = macvlan_hash_lookup(port, eth->h_source);
177 		if (!src)
178 			/* frame comes from an external address */
179 			macvlan_broadcast(skb, port, NULL,
180 					  MACVLAN_MODE_PRIVATE |
181 					  MACVLAN_MODE_VEPA    |
182 					  MACVLAN_MODE_PASSTHRU|
183 					  MACVLAN_MODE_BRIDGE);
184 		else if (src->mode == MACVLAN_MODE_VEPA)
185 			/* flood to everyone except source */
186 			macvlan_broadcast(skb, port, src->dev,
187 					  MACVLAN_MODE_VEPA |
188 					  MACVLAN_MODE_BRIDGE);
189 		else if (src->mode == MACVLAN_MODE_BRIDGE)
190 			/*
191 			 * flood only to VEPA ports, bridge ports
192 			 * already saw the frame on the way out.
193 			 */
194 			macvlan_broadcast(skb, port, src->dev,
195 					  MACVLAN_MODE_VEPA);
196 		else {
197 			/* forward to original port. */
198 			vlan = src;
199 			ret = macvlan_broadcast_one(skb, vlan, eth, 0);
200 			goto out;
201 		}
202 
203 		return RX_HANDLER_PASS;
204 	}
205 
206 	if (port->passthru)
207 		vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
208 	else
209 		vlan = macvlan_hash_lookup(port, eth->h_dest);
210 	if (vlan == NULL)
211 		return RX_HANDLER_PASS;
212 
213 	dev = vlan->dev;
214 	if (unlikely(!(dev->flags & IFF_UP))) {
215 		kfree_skb(skb);
216 		return RX_HANDLER_CONSUMED;
217 	}
218 	len = skb->len + ETH_HLEN;
219 	skb = skb_share_check(skb, GFP_ATOMIC);
220 	if (!skb)
221 		goto out;
222 
223 	skb->dev = dev;
224 	skb->pkt_type = PACKET_HOST;
225 
226 	ret = vlan->receive(skb);
227 
228 out:
229 	macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
230 	return RX_HANDLER_CONSUMED;
231 }
232 
233 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
234 {
235 	const struct macvlan_dev *vlan = netdev_priv(dev);
236 	const struct macvlan_port *port = vlan->port;
237 	const struct macvlan_dev *dest;
238 	__u8 ip_summed = skb->ip_summed;
239 
240 	if (vlan->mode == MACVLAN_MODE_BRIDGE) {
241 		const struct ethhdr *eth = (void *)skb->data;
242 		skb->ip_summed = CHECKSUM_UNNECESSARY;
243 
244 		/* send to other bridge ports directly */
245 		if (is_multicast_ether_addr(eth->h_dest)) {
246 			macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
247 			goto xmit_world;
248 		}
249 
250 		dest = macvlan_hash_lookup(port, eth->h_dest);
251 		if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
252 			/* send to lowerdev first for its network taps */
253 			dev_forward_skb(vlan->lowerdev, skb);
254 
255 			return NET_XMIT_SUCCESS;
256 		}
257 	}
258 
259 xmit_world:
260 	skb->ip_summed = ip_summed;
261 	skb_set_dev(skb, vlan->lowerdev);
262 	return dev_queue_xmit(skb);
263 }
264 
265 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
266 			       struct net_device *dev)
267 {
268 	unsigned int len = skb->len;
269 	int ret;
270 	const struct macvlan_dev *vlan = netdev_priv(dev);
271 
272 	ret = macvlan_queue_xmit(skb, dev);
273 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
274 		struct macvlan_pcpu_stats *pcpu_stats;
275 
276 		pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
277 		u64_stats_update_begin(&pcpu_stats->syncp);
278 		pcpu_stats->tx_packets++;
279 		pcpu_stats->tx_bytes += len;
280 		u64_stats_update_end(&pcpu_stats->syncp);
281 	} else {
282 		this_cpu_inc(vlan->pcpu_stats->tx_dropped);
283 	}
284 	return ret;
285 }
286 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
287 
288 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
289 			       unsigned short type, const void *daddr,
290 			       const void *saddr, unsigned len)
291 {
292 	const struct macvlan_dev *vlan = netdev_priv(dev);
293 	struct net_device *lowerdev = vlan->lowerdev;
294 
295 	return dev_hard_header(skb, lowerdev, type, daddr,
296 			       saddr ? : dev->dev_addr, len);
297 }
298 
299 static const struct header_ops macvlan_hard_header_ops = {
300 	.create  	= macvlan_hard_header,
301 	.rebuild	= eth_rebuild_header,
302 	.parse		= eth_header_parse,
303 	.cache		= eth_header_cache,
304 	.cache_update	= eth_header_cache_update,
305 };
306 
307 static int macvlan_open(struct net_device *dev)
308 {
309 	struct macvlan_dev *vlan = netdev_priv(dev);
310 	struct net_device *lowerdev = vlan->lowerdev;
311 	int err;
312 
313 	if (vlan->port->passthru) {
314 		dev_set_promiscuity(lowerdev, 1);
315 		goto hash_add;
316 	}
317 
318 	err = -EBUSY;
319 	if (macvlan_addr_busy(vlan->port, dev->dev_addr))
320 		goto out;
321 
322 	err = dev_uc_add(lowerdev, dev->dev_addr);
323 	if (err < 0)
324 		goto out;
325 	if (dev->flags & IFF_ALLMULTI) {
326 		err = dev_set_allmulti(lowerdev, 1);
327 		if (err < 0)
328 			goto del_unicast;
329 	}
330 
331 hash_add:
332 	macvlan_hash_add(vlan);
333 	return 0;
334 
335 del_unicast:
336 	dev_uc_del(lowerdev, dev->dev_addr);
337 out:
338 	return err;
339 }
340 
341 static int macvlan_stop(struct net_device *dev)
342 {
343 	struct macvlan_dev *vlan = netdev_priv(dev);
344 	struct net_device *lowerdev = vlan->lowerdev;
345 
346 	if (vlan->port->passthru) {
347 		dev_set_promiscuity(lowerdev, -1);
348 		goto hash_del;
349 	}
350 
351 	dev_mc_unsync(lowerdev, dev);
352 	if (dev->flags & IFF_ALLMULTI)
353 		dev_set_allmulti(lowerdev, -1);
354 
355 	dev_uc_del(lowerdev, dev->dev_addr);
356 
357 hash_del:
358 	macvlan_hash_del(vlan, !dev->dismantle);
359 	return 0;
360 }
361 
362 static int macvlan_set_mac_address(struct net_device *dev, void *p)
363 {
364 	struct macvlan_dev *vlan = netdev_priv(dev);
365 	struct net_device *lowerdev = vlan->lowerdev;
366 	struct sockaddr *addr = p;
367 	int err;
368 
369 	if (!is_valid_ether_addr(addr->sa_data))
370 		return -EADDRNOTAVAIL;
371 
372 	if (!(dev->flags & IFF_UP)) {
373 		/* Just copy in the new address */
374 		memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
375 	} else {
376 		/* Rehash and update the device filters */
377 		if (macvlan_addr_busy(vlan->port, addr->sa_data))
378 			return -EBUSY;
379 
380 		err = dev_uc_add(lowerdev, addr->sa_data);
381 		if (err)
382 			return err;
383 
384 		dev_uc_del(lowerdev, dev->dev_addr);
385 
386 		macvlan_hash_change_addr(vlan, addr->sa_data);
387 	}
388 	return 0;
389 }
390 
391 static void macvlan_change_rx_flags(struct net_device *dev, int change)
392 {
393 	struct macvlan_dev *vlan = netdev_priv(dev);
394 	struct net_device *lowerdev = vlan->lowerdev;
395 
396 	if (change & IFF_ALLMULTI)
397 		dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
398 }
399 
400 static void macvlan_set_multicast_list(struct net_device *dev)
401 {
402 	struct macvlan_dev *vlan = netdev_priv(dev);
403 
404 	dev_mc_sync(vlan->lowerdev, dev);
405 }
406 
407 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
408 {
409 	struct macvlan_dev *vlan = netdev_priv(dev);
410 
411 	if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
412 		return -EINVAL;
413 	dev->mtu = new_mtu;
414 	return 0;
415 }
416 
417 /*
418  * macvlan network devices have devices nesting below it and are a special
419  * "super class" of normal network devices; split their locks off into a
420  * separate class since they always nest.
421  */
422 static struct lock_class_key macvlan_netdev_xmit_lock_key;
423 static struct lock_class_key macvlan_netdev_addr_lock_key;
424 
425 #define MACVLAN_FEATURES \
426 	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
427 	 NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
428 	 NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
429 	 NETIF_F_HW_VLAN_FILTER)
430 
431 #define MACVLAN_STATE_MASK \
432 	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
433 
434 static void macvlan_set_lockdep_class_one(struct net_device *dev,
435 					  struct netdev_queue *txq,
436 					  void *_unused)
437 {
438 	lockdep_set_class(&txq->_xmit_lock,
439 			  &macvlan_netdev_xmit_lock_key);
440 }
441 
442 static void macvlan_set_lockdep_class(struct net_device *dev)
443 {
444 	lockdep_set_class(&dev->addr_list_lock,
445 			  &macvlan_netdev_addr_lock_key);
446 	netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
447 }
448 
449 static int macvlan_init(struct net_device *dev)
450 {
451 	struct macvlan_dev *vlan = netdev_priv(dev);
452 	const struct net_device *lowerdev = vlan->lowerdev;
453 
454 	dev->state		= (dev->state & ~MACVLAN_STATE_MASK) |
455 				  (lowerdev->state & MACVLAN_STATE_MASK);
456 	dev->features 		= lowerdev->features & MACVLAN_FEATURES;
457 	dev->features		|= NETIF_F_LLTX;
458 	dev->gso_max_size	= lowerdev->gso_max_size;
459 	dev->iflink		= lowerdev->ifindex;
460 	dev->hard_header_len	= lowerdev->hard_header_len;
461 
462 	macvlan_set_lockdep_class(dev);
463 
464 	vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
465 	if (!vlan->pcpu_stats)
466 		return -ENOMEM;
467 
468 	return 0;
469 }
470 
471 static void macvlan_uninit(struct net_device *dev)
472 {
473 	struct macvlan_dev *vlan = netdev_priv(dev);
474 	struct macvlan_port *port = vlan->port;
475 
476 	free_percpu(vlan->pcpu_stats);
477 
478 	port->count -= 1;
479 	if (!port->count)
480 		macvlan_port_destroy(port->dev);
481 }
482 
483 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
484 							 struct rtnl_link_stats64 *stats)
485 {
486 	struct macvlan_dev *vlan = netdev_priv(dev);
487 
488 	if (vlan->pcpu_stats) {
489 		struct macvlan_pcpu_stats *p;
490 		u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
491 		u32 rx_errors = 0, tx_dropped = 0;
492 		unsigned int start;
493 		int i;
494 
495 		for_each_possible_cpu(i) {
496 			p = per_cpu_ptr(vlan->pcpu_stats, i);
497 			do {
498 				start = u64_stats_fetch_begin_bh(&p->syncp);
499 				rx_packets	= p->rx_packets;
500 				rx_bytes	= p->rx_bytes;
501 				rx_multicast	= p->rx_multicast;
502 				tx_packets	= p->tx_packets;
503 				tx_bytes	= p->tx_bytes;
504 			} while (u64_stats_fetch_retry_bh(&p->syncp, start));
505 
506 			stats->rx_packets	+= rx_packets;
507 			stats->rx_bytes		+= rx_bytes;
508 			stats->multicast	+= rx_multicast;
509 			stats->tx_packets	+= tx_packets;
510 			stats->tx_bytes		+= tx_bytes;
511 			/* rx_errors & tx_dropped are u32, updated
512 			 * without syncp protection.
513 			 */
514 			rx_errors	+= p->rx_errors;
515 			tx_dropped	+= p->tx_dropped;
516 		}
517 		stats->rx_errors	= rx_errors;
518 		stats->rx_dropped	= rx_errors;
519 		stats->tx_dropped	= tx_dropped;
520 	}
521 	return stats;
522 }
523 
524 static int macvlan_vlan_rx_add_vid(struct net_device *dev,
525 				    unsigned short vid)
526 {
527 	struct macvlan_dev *vlan = netdev_priv(dev);
528 	struct net_device *lowerdev = vlan->lowerdev;
529 
530 	return vlan_vid_add(lowerdev, vid);
531 }
532 
533 static int macvlan_vlan_rx_kill_vid(struct net_device *dev,
534 				     unsigned short vid)
535 {
536 	struct macvlan_dev *vlan = netdev_priv(dev);
537 	struct net_device *lowerdev = vlan->lowerdev;
538 
539 	vlan_vid_del(lowerdev, vid);
540 	return 0;
541 }
542 
543 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
544 					struct ethtool_drvinfo *drvinfo)
545 {
546 	snprintf(drvinfo->driver, 32, "macvlan");
547 	snprintf(drvinfo->version, 32, "0.1");
548 }
549 
550 static int macvlan_ethtool_get_settings(struct net_device *dev,
551 					struct ethtool_cmd *cmd)
552 {
553 	const struct macvlan_dev *vlan = netdev_priv(dev);
554 
555 	return __ethtool_get_settings(vlan->lowerdev, cmd);
556 }
557 
558 static const struct ethtool_ops macvlan_ethtool_ops = {
559 	.get_link		= ethtool_op_get_link,
560 	.get_settings		= macvlan_ethtool_get_settings,
561 	.get_drvinfo		= macvlan_ethtool_get_drvinfo,
562 };
563 
564 static const struct net_device_ops macvlan_netdev_ops = {
565 	.ndo_init		= macvlan_init,
566 	.ndo_uninit		= macvlan_uninit,
567 	.ndo_open		= macvlan_open,
568 	.ndo_stop		= macvlan_stop,
569 	.ndo_start_xmit		= macvlan_start_xmit,
570 	.ndo_change_mtu		= macvlan_change_mtu,
571 	.ndo_change_rx_flags	= macvlan_change_rx_flags,
572 	.ndo_set_mac_address	= macvlan_set_mac_address,
573 	.ndo_set_rx_mode	= macvlan_set_multicast_list,
574 	.ndo_get_stats64	= macvlan_dev_get_stats64,
575 	.ndo_validate_addr	= eth_validate_addr,
576 	.ndo_vlan_rx_add_vid	= macvlan_vlan_rx_add_vid,
577 	.ndo_vlan_rx_kill_vid	= macvlan_vlan_rx_kill_vid,
578 };
579 
580 void macvlan_common_setup(struct net_device *dev)
581 {
582 	ether_setup(dev);
583 
584 	dev->priv_flags	       &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
585 	dev->netdev_ops		= &macvlan_netdev_ops;
586 	dev->destructor		= free_netdev;
587 	dev->header_ops		= &macvlan_hard_header_ops,
588 	dev->ethtool_ops	= &macvlan_ethtool_ops;
589 }
590 EXPORT_SYMBOL_GPL(macvlan_common_setup);
591 
592 static void macvlan_setup(struct net_device *dev)
593 {
594 	macvlan_common_setup(dev);
595 	dev->tx_queue_len	= 0;
596 }
597 
598 static int macvlan_port_create(struct net_device *dev)
599 {
600 	struct macvlan_port *port;
601 	unsigned int i;
602 	int err;
603 
604 	if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
605 		return -EINVAL;
606 
607 	port = kzalloc(sizeof(*port), GFP_KERNEL);
608 	if (port == NULL)
609 		return -ENOMEM;
610 
611 	port->passthru = false;
612 	port->dev = dev;
613 	INIT_LIST_HEAD(&port->vlans);
614 	for (i = 0; i < MACVLAN_HASH_SIZE; i++)
615 		INIT_HLIST_HEAD(&port->vlan_hash[i]);
616 
617 	err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
618 	if (err)
619 		kfree(port);
620 	else
621 		dev->priv_flags |= IFF_MACVLAN_PORT;
622 	return err;
623 }
624 
625 static void macvlan_port_destroy(struct net_device *dev)
626 {
627 	struct macvlan_port *port = macvlan_port_get(dev);
628 
629 	dev->priv_flags &= ~IFF_MACVLAN_PORT;
630 	netdev_rx_handler_unregister(dev);
631 	kfree_rcu(port, rcu);
632 }
633 
634 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
635 {
636 	if (tb[IFLA_ADDRESS]) {
637 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
638 			return -EINVAL;
639 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
640 			return -EADDRNOTAVAIL;
641 	}
642 
643 	if (data && data[IFLA_MACVLAN_MODE]) {
644 		switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
645 		case MACVLAN_MODE_PRIVATE:
646 		case MACVLAN_MODE_VEPA:
647 		case MACVLAN_MODE_BRIDGE:
648 		case MACVLAN_MODE_PASSTHRU:
649 			break;
650 		default:
651 			return -EINVAL;
652 		}
653 	}
654 	return 0;
655 }
656 
657 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
658 			   struct nlattr *tb[], struct nlattr *data[],
659 			   int (*receive)(struct sk_buff *skb),
660 			   int (*forward)(struct net_device *dev,
661 					  struct sk_buff *skb))
662 {
663 	struct macvlan_dev *vlan = netdev_priv(dev);
664 	struct macvlan_port *port;
665 	struct net_device *lowerdev;
666 	int err;
667 
668 	if (!tb[IFLA_LINK])
669 		return -EINVAL;
670 
671 	lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
672 	if (lowerdev == NULL)
673 		return -ENODEV;
674 
675 	/* When creating macvlans on top of other macvlans - use
676 	 * the real device as the lowerdev.
677 	 */
678 	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
679 		struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
680 		lowerdev = lowervlan->lowerdev;
681 	}
682 
683 	if (!tb[IFLA_MTU])
684 		dev->mtu = lowerdev->mtu;
685 	else if (dev->mtu > lowerdev->mtu)
686 		return -EINVAL;
687 
688 	if (!tb[IFLA_ADDRESS])
689 		random_ether_addr(dev->dev_addr);
690 
691 	if (!macvlan_port_exists(lowerdev)) {
692 		err = macvlan_port_create(lowerdev);
693 		if (err < 0)
694 			return err;
695 	}
696 	port = macvlan_port_get(lowerdev);
697 
698 	/* Only 1 macvlan device can be created in passthru mode */
699 	if (port->passthru)
700 		return -EINVAL;
701 
702 	vlan->lowerdev = lowerdev;
703 	vlan->dev      = dev;
704 	vlan->port     = port;
705 	vlan->receive  = receive;
706 	vlan->forward  = forward;
707 
708 	vlan->mode     = MACVLAN_MODE_VEPA;
709 	if (data && data[IFLA_MACVLAN_MODE])
710 		vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
711 
712 	if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
713 		if (port->count)
714 			return -EINVAL;
715 		port->passthru = true;
716 		memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
717 	}
718 
719 	port->count += 1;
720 	err = register_netdevice(dev);
721 	if (err < 0)
722 		goto destroy_port;
723 
724 	list_add_tail(&vlan->list, &port->vlans);
725 	netif_stacked_transfer_operstate(lowerdev, dev);
726 
727 	return 0;
728 
729 destroy_port:
730 	port->count -= 1;
731 	if (!port->count)
732 		macvlan_port_destroy(lowerdev);
733 
734 	return err;
735 }
736 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
737 
738 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
739 			   struct nlattr *tb[], struct nlattr *data[])
740 {
741 	return macvlan_common_newlink(src_net, dev, tb, data,
742 				      netif_rx,
743 				      dev_forward_skb);
744 }
745 
746 void macvlan_dellink(struct net_device *dev, struct list_head *head)
747 {
748 	struct macvlan_dev *vlan = netdev_priv(dev);
749 
750 	list_del(&vlan->list);
751 	unregister_netdevice_queue(dev, head);
752 }
753 EXPORT_SYMBOL_GPL(macvlan_dellink);
754 
755 static int macvlan_changelink(struct net_device *dev,
756 		struct nlattr *tb[], struct nlattr *data[])
757 {
758 	struct macvlan_dev *vlan = netdev_priv(dev);
759 	if (data && data[IFLA_MACVLAN_MODE])
760 		vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
761 	return 0;
762 }
763 
764 static size_t macvlan_get_size(const struct net_device *dev)
765 {
766 	return nla_total_size(4);
767 }
768 
769 static int macvlan_fill_info(struct sk_buff *skb,
770 				const struct net_device *dev)
771 {
772 	struct macvlan_dev *vlan = netdev_priv(dev);
773 
774 	NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
775 	return 0;
776 
777 nla_put_failure:
778 	return -EMSGSIZE;
779 }
780 
781 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
782 	[IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
783 };
784 
785 int macvlan_link_register(struct rtnl_link_ops *ops)
786 {
787 	/* common fields */
788 	ops->priv_size		= sizeof(struct macvlan_dev);
789 	ops->validate		= macvlan_validate;
790 	ops->maxtype		= IFLA_MACVLAN_MAX;
791 	ops->policy		= macvlan_policy;
792 	ops->changelink		= macvlan_changelink;
793 	ops->get_size		= macvlan_get_size;
794 	ops->fill_info		= macvlan_fill_info;
795 
796 	return rtnl_link_register(ops);
797 };
798 EXPORT_SYMBOL_GPL(macvlan_link_register);
799 
800 static struct rtnl_link_ops macvlan_link_ops = {
801 	.kind		= "macvlan",
802 	.setup		= macvlan_setup,
803 	.newlink	= macvlan_newlink,
804 	.dellink	= macvlan_dellink,
805 };
806 
807 static int macvlan_device_event(struct notifier_block *unused,
808 				unsigned long event, void *ptr)
809 {
810 	struct net_device *dev = ptr;
811 	struct macvlan_dev *vlan, *next;
812 	struct macvlan_port *port;
813 	LIST_HEAD(list_kill);
814 
815 	if (!macvlan_port_exists(dev))
816 		return NOTIFY_DONE;
817 
818 	port = macvlan_port_get(dev);
819 
820 	switch (event) {
821 	case NETDEV_CHANGE:
822 		list_for_each_entry(vlan, &port->vlans, list)
823 			netif_stacked_transfer_operstate(vlan->lowerdev,
824 							 vlan->dev);
825 		break;
826 	case NETDEV_FEAT_CHANGE:
827 		list_for_each_entry(vlan, &port->vlans, list) {
828 			vlan->dev->features = dev->features & MACVLAN_FEATURES;
829 			vlan->dev->gso_max_size = dev->gso_max_size;
830 			netdev_features_change(vlan->dev);
831 		}
832 		break;
833 	case NETDEV_UNREGISTER:
834 		/* twiddle thumbs on netns device moves */
835 		if (dev->reg_state != NETREG_UNREGISTERING)
836 			break;
837 
838 		list_for_each_entry_safe(vlan, next, &port->vlans, list)
839 			vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
840 		unregister_netdevice_many(&list_kill);
841 		list_del(&list_kill);
842 		break;
843 	case NETDEV_PRE_TYPE_CHANGE:
844 		/* Forbid underlaying device to change its type. */
845 		return NOTIFY_BAD;
846 	}
847 	return NOTIFY_DONE;
848 }
849 
850 static struct notifier_block macvlan_notifier_block __read_mostly = {
851 	.notifier_call	= macvlan_device_event,
852 };
853 
854 static int __init macvlan_init_module(void)
855 {
856 	int err;
857 
858 	register_netdevice_notifier(&macvlan_notifier_block);
859 
860 	err = macvlan_link_register(&macvlan_link_ops);
861 	if (err < 0)
862 		goto err1;
863 	return 0;
864 err1:
865 	unregister_netdevice_notifier(&macvlan_notifier_block);
866 	return err;
867 }
868 
869 static void __exit macvlan_cleanup_module(void)
870 {
871 	rtnl_link_unregister(&macvlan_link_ops);
872 	unregister_netdevice_notifier(&macvlan_notifier_block);
873 }
874 
875 module_init(macvlan_init_module);
876 module_exit(macvlan_cleanup_module);
877 
878 MODULE_LICENSE("GPL");
879 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
880 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
881 MODULE_ALIAS_RTNL_LINK("macvlan");
882