xref: /openbmc/linux/drivers/net/ipvlan/ipvlan_main.c (revision 36d26912)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
3  */
4 
5 #include "ipvlan.h"
6 
7 static int ipvlan_set_port_mode(struct ipvl_port *port, u16 nval,
8 				struct netlink_ext_ack *extack)
9 {
10 	struct ipvl_dev *ipvlan;
11 	unsigned int flags;
12 	int err;
13 
14 	ASSERT_RTNL();
15 	if (port->mode != nval) {
16 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
17 			flags = ipvlan->dev->flags;
18 			if (nval == IPVLAN_MODE_L3 || nval == IPVLAN_MODE_L3S) {
19 				err = dev_change_flags(ipvlan->dev,
20 						       flags | IFF_NOARP,
21 						       extack);
22 			} else {
23 				err = dev_change_flags(ipvlan->dev,
24 						       flags & ~IFF_NOARP,
25 						       extack);
26 			}
27 			if (unlikely(err))
28 				goto fail;
29 		}
30 		if (nval == IPVLAN_MODE_L3S) {
31 			/* New mode is L3S */
32 			err = ipvlan_l3s_register(port);
33 			if (err)
34 				goto fail;
35 		} else if (port->mode == IPVLAN_MODE_L3S) {
36 			/* Old mode was L3S */
37 			ipvlan_l3s_unregister(port);
38 		}
39 		port->mode = nval;
40 	}
41 	return 0;
42 
43 fail:
44 	/* Undo the flags changes that have been done so far. */
45 	list_for_each_entry_continue_reverse(ipvlan, &port->ipvlans, pnode) {
46 		flags = ipvlan->dev->flags;
47 		if (port->mode == IPVLAN_MODE_L3 ||
48 		    port->mode == IPVLAN_MODE_L3S)
49 			dev_change_flags(ipvlan->dev, flags | IFF_NOARP,
50 					 NULL);
51 		else
52 			dev_change_flags(ipvlan->dev, flags & ~IFF_NOARP,
53 					 NULL);
54 	}
55 
56 	return err;
57 }
58 
59 static int ipvlan_port_create(struct net_device *dev)
60 {
61 	struct ipvl_port *port;
62 	int err, idx;
63 
64 	port = kzalloc(sizeof(struct ipvl_port), GFP_KERNEL);
65 	if (!port)
66 		return -ENOMEM;
67 
68 	write_pnet(&port->pnet, dev_net(dev));
69 	port->dev = dev;
70 	port->mode = IPVLAN_MODE_L3;
71 	INIT_LIST_HEAD(&port->ipvlans);
72 	for (idx = 0; idx < IPVLAN_HASH_SIZE; idx++)
73 		INIT_HLIST_HEAD(&port->hlhead[idx]);
74 
75 	skb_queue_head_init(&port->backlog);
76 	INIT_WORK(&port->wq, ipvlan_process_multicast);
77 	ida_init(&port->ida);
78 	port->dev_id_start = 1;
79 
80 	err = netdev_rx_handler_register(dev, ipvlan_handle_frame, port);
81 	if (err)
82 		goto err;
83 
84 	return 0;
85 
86 err:
87 	kfree(port);
88 	return err;
89 }
90 
91 static void ipvlan_port_destroy(struct net_device *dev)
92 {
93 	struct ipvl_port *port = ipvlan_port_get_rtnl(dev);
94 	struct sk_buff *skb;
95 
96 	if (port->mode == IPVLAN_MODE_L3S)
97 		ipvlan_l3s_unregister(port);
98 	netdev_rx_handler_unregister(dev);
99 	cancel_work_sync(&port->wq);
100 	while ((skb = __skb_dequeue(&port->backlog)) != NULL) {
101 		if (skb->dev)
102 			dev_put(skb->dev);
103 		kfree_skb(skb);
104 	}
105 	ida_destroy(&port->ida);
106 	kfree(port);
107 }
108 
109 #define IPVLAN_ALWAYS_ON_OFLOADS \
110 	(NETIF_F_SG | NETIF_F_HW_CSUM | \
111 	 NETIF_F_GSO_ROBUST | NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL)
112 
113 #define IPVLAN_ALWAYS_ON \
114 	(IPVLAN_ALWAYS_ON_OFLOADS | NETIF_F_LLTX | NETIF_F_VLAN_CHALLENGED)
115 
116 #define IPVLAN_FEATURES \
117 	(NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
118 	 NETIF_F_GSO | NETIF_F_ALL_TSO | NETIF_F_GSO_ROBUST | \
119 	 NETIF_F_GRO | NETIF_F_RXCSUM | \
120 	 NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER)
121 
122 	/* NETIF_F_GSO_ENCAP_ALL NETIF_F_GSO_SOFTWARE Newly added */
123 
124 #define IPVLAN_STATE_MASK \
125 	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
126 
127 static int ipvlan_init(struct net_device *dev)
128 {
129 	struct ipvl_dev *ipvlan = netdev_priv(dev);
130 	struct net_device *phy_dev = ipvlan->phy_dev;
131 	struct ipvl_port *port;
132 	int err;
133 
134 	dev->state = (dev->state & ~IPVLAN_STATE_MASK) |
135 		     (phy_dev->state & IPVLAN_STATE_MASK);
136 	dev->features = phy_dev->features & IPVLAN_FEATURES;
137 	dev->features |= IPVLAN_ALWAYS_ON;
138 	dev->vlan_features = phy_dev->vlan_features & IPVLAN_FEATURES;
139 	dev->vlan_features |= IPVLAN_ALWAYS_ON_OFLOADS;
140 	dev->hw_enc_features |= dev->features;
141 	dev->gso_max_size = phy_dev->gso_max_size;
142 	dev->gso_max_segs = phy_dev->gso_max_segs;
143 	dev->hard_header_len = phy_dev->hard_header_len;
144 
145 	netdev_lockdep_set_classes(dev);
146 
147 	ipvlan->pcpu_stats = netdev_alloc_pcpu_stats(struct ipvl_pcpu_stats);
148 	if (!ipvlan->pcpu_stats)
149 		return -ENOMEM;
150 
151 	if (!netif_is_ipvlan_port(phy_dev)) {
152 		err = ipvlan_port_create(phy_dev);
153 		if (err < 0) {
154 			free_percpu(ipvlan->pcpu_stats);
155 			return err;
156 		}
157 	}
158 	port = ipvlan_port_get_rtnl(phy_dev);
159 	port->count += 1;
160 	return 0;
161 }
162 
163 static void ipvlan_uninit(struct net_device *dev)
164 {
165 	struct ipvl_dev *ipvlan = netdev_priv(dev);
166 	struct net_device *phy_dev = ipvlan->phy_dev;
167 	struct ipvl_port *port;
168 
169 	free_percpu(ipvlan->pcpu_stats);
170 
171 	port = ipvlan_port_get_rtnl(phy_dev);
172 	port->count -= 1;
173 	if (!port->count)
174 		ipvlan_port_destroy(port->dev);
175 }
176 
177 static int ipvlan_open(struct net_device *dev)
178 {
179 	struct ipvl_dev *ipvlan = netdev_priv(dev);
180 	struct ipvl_addr *addr;
181 
182 	if (ipvlan->port->mode == IPVLAN_MODE_L3 ||
183 	    ipvlan->port->mode == IPVLAN_MODE_L3S)
184 		dev->flags |= IFF_NOARP;
185 	else
186 		dev->flags &= ~IFF_NOARP;
187 
188 	rcu_read_lock();
189 	list_for_each_entry_rcu(addr, &ipvlan->addrs, anode)
190 		ipvlan_ht_addr_add(ipvlan, addr);
191 	rcu_read_unlock();
192 
193 	return 0;
194 }
195 
196 static int ipvlan_stop(struct net_device *dev)
197 {
198 	struct ipvl_dev *ipvlan = netdev_priv(dev);
199 	struct net_device *phy_dev = ipvlan->phy_dev;
200 	struct ipvl_addr *addr;
201 
202 	dev_uc_unsync(phy_dev, dev);
203 	dev_mc_unsync(phy_dev, dev);
204 
205 	rcu_read_lock();
206 	list_for_each_entry_rcu(addr, &ipvlan->addrs, anode)
207 		ipvlan_ht_addr_del(addr);
208 	rcu_read_unlock();
209 
210 	return 0;
211 }
212 
213 static netdev_tx_t ipvlan_start_xmit(struct sk_buff *skb,
214 				     struct net_device *dev)
215 {
216 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
217 	int skblen = skb->len;
218 	int ret;
219 
220 	ret = ipvlan_queue_xmit(skb, dev);
221 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
222 		struct ipvl_pcpu_stats *pcptr;
223 
224 		pcptr = this_cpu_ptr(ipvlan->pcpu_stats);
225 
226 		u64_stats_update_begin(&pcptr->syncp);
227 		pcptr->tx_pkts++;
228 		pcptr->tx_bytes += skblen;
229 		u64_stats_update_end(&pcptr->syncp);
230 	} else {
231 		this_cpu_inc(ipvlan->pcpu_stats->tx_drps);
232 	}
233 	return ret;
234 }
235 
236 static netdev_features_t ipvlan_fix_features(struct net_device *dev,
237 					     netdev_features_t features)
238 {
239 	struct ipvl_dev *ipvlan = netdev_priv(dev);
240 
241 	features |= NETIF_F_ALL_FOR_ALL;
242 	features &= (ipvlan->sfeatures | ~IPVLAN_FEATURES);
243 	features = netdev_increment_features(ipvlan->phy_dev->features,
244 					     features, features);
245 	features |= IPVLAN_ALWAYS_ON;
246 	features &= (IPVLAN_FEATURES | IPVLAN_ALWAYS_ON);
247 
248 	return features;
249 }
250 
251 static void ipvlan_change_rx_flags(struct net_device *dev, int change)
252 {
253 	struct ipvl_dev *ipvlan = netdev_priv(dev);
254 	struct net_device *phy_dev = ipvlan->phy_dev;
255 
256 	if (change & IFF_ALLMULTI)
257 		dev_set_allmulti(phy_dev, dev->flags & IFF_ALLMULTI? 1 : -1);
258 }
259 
260 static void ipvlan_set_multicast_mac_filter(struct net_device *dev)
261 {
262 	struct ipvl_dev *ipvlan = netdev_priv(dev);
263 
264 	if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
265 		bitmap_fill(ipvlan->mac_filters, IPVLAN_MAC_FILTER_SIZE);
266 	} else {
267 		struct netdev_hw_addr *ha;
268 		DECLARE_BITMAP(mc_filters, IPVLAN_MAC_FILTER_SIZE);
269 
270 		bitmap_zero(mc_filters, IPVLAN_MAC_FILTER_SIZE);
271 		netdev_for_each_mc_addr(ha, dev)
272 			__set_bit(ipvlan_mac_hash(ha->addr), mc_filters);
273 
274 		/* Turn-on broadcast bit irrespective of address family,
275 		 * since broadcast is deferred to a work-queue, hence no
276 		 * impact on fast-path processing.
277 		 */
278 		__set_bit(ipvlan_mac_hash(dev->broadcast), mc_filters);
279 
280 		bitmap_copy(ipvlan->mac_filters, mc_filters,
281 			    IPVLAN_MAC_FILTER_SIZE);
282 	}
283 	dev_uc_sync(ipvlan->phy_dev, dev);
284 	dev_mc_sync(ipvlan->phy_dev, dev);
285 }
286 
287 static void ipvlan_get_stats64(struct net_device *dev,
288 			       struct rtnl_link_stats64 *s)
289 {
290 	struct ipvl_dev *ipvlan = netdev_priv(dev);
291 
292 	if (ipvlan->pcpu_stats) {
293 		struct ipvl_pcpu_stats *pcptr;
294 		u64 rx_pkts, rx_bytes, rx_mcast, tx_pkts, tx_bytes;
295 		u32 rx_errs = 0, tx_drps = 0;
296 		u32 strt;
297 		int idx;
298 
299 		for_each_possible_cpu(idx) {
300 			pcptr = per_cpu_ptr(ipvlan->pcpu_stats, idx);
301 			do {
302 				strt= u64_stats_fetch_begin_irq(&pcptr->syncp);
303 				rx_pkts = pcptr->rx_pkts;
304 				rx_bytes = pcptr->rx_bytes;
305 				rx_mcast = pcptr->rx_mcast;
306 				tx_pkts = pcptr->tx_pkts;
307 				tx_bytes = pcptr->tx_bytes;
308 			} while (u64_stats_fetch_retry_irq(&pcptr->syncp,
309 							   strt));
310 
311 			s->rx_packets += rx_pkts;
312 			s->rx_bytes += rx_bytes;
313 			s->multicast += rx_mcast;
314 			s->tx_packets += tx_pkts;
315 			s->tx_bytes += tx_bytes;
316 
317 			/* u32 values are updated without syncp protection. */
318 			rx_errs += pcptr->rx_errs;
319 			tx_drps += pcptr->tx_drps;
320 		}
321 		s->rx_errors = rx_errs;
322 		s->rx_dropped = rx_errs;
323 		s->tx_dropped = tx_drps;
324 	}
325 }
326 
327 static int ipvlan_vlan_rx_add_vid(struct net_device *dev, __be16 proto, u16 vid)
328 {
329 	struct ipvl_dev *ipvlan = netdev_priv(dev);
330 	struct net_device *phy_dev = ipvlan->phy_dev;
331 
332 	return vlan_vid_add(phy_dev, proto, vid);
333 }
334 
335 static int ipvlan_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
336 				   u16 vid)
337 {
338 	struct ipvl_dev *ipvlan = netdev_priv(dev);
339 	struct net_device *phy_dev = ipvlan->phy_dev;
340 
341 	vlan_vid_del(phy_dev, proto, vid);
342 	return 0;
343 }
344 
345 static int ipvlan_get_iflink(const struct net_device *dev)
346 {
347 	struct ipvl_dev *ipvlan = netdev_priv(dev);
348 
349 	return ipvlan->phy_dev->ifindex;
350 }
351 
352 static const struct net_device_ops ipvlan_netdev_ops = {
353 	.ndo_init		= ipvlan_init,
354 	.ndo_uninit		= ipvlan_uninit,
355 	.ndo_open		= ipvlan_open,
356 	.ndo_stop		= ipvlan_stop,
357 	.ndo_start_xmit		= ipvlan_start_xmit,
358 	.ndo_fix_features	= ipvlan_fix_features,
359 	.ndo_change_rx_flags	= ipvlan_change_rx_flags,
360 	.ndo_set_rx_mode	= ipvlan_set_multicast_mac_filter,
361 	.ndo_get_stats64	= ipvlan_get_stats64,
362 	.ndo_vlan_rx_add_vid	= ipvlan_vlan_rx_add_vid,
363 	.ndo_vlan_rx_kill_vid	= ipvlan_vlan_rx_kill_vid,
364 	.ndo_get_iflink		= ipvlan_get_iflink,
365 };
366 
367 static int ipvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
368 			      unsigned short type, const void *daddr,
369 			      const void *saddr, unsigned len)
370 {
371 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
372 	struct net_device *phy_dev = ipvlan->phy_dev;
373 
374 	/* TODO Probably use a different field than dev_addr so that the
375 	 * mac-address on the virtual device is portable and can be carried
376 	 * while the packets use the mac-addr on the physical device.
377 	 */
378 	return dev_hard_header(skb, phy_dev, type, daddr,
379 			       saddr ? : phy_dev->dev_addr, len);
380 }
381 
382 static const struct header_ops ipvlan_header_ops = {
383 	.create  	= ipvlan_hard_header,
384 	.parse		= eth_header_parse,
385 	.cache		= eth_header_cache,
386 	.cache_update	= eth_header_cache_update,
387 };
388 
389 static void ipvlan_adjust_mtu(struct ipvl_dev *ipvlan, struct net_device *dev)
390 {
391 	ipvlan->dev->mtu = dev->mtu;
392 }
393 
394 static bool netif_is_ipvlan(const struct net_device *dev)
395 {
396 	/* both ipvlan and ipvtap devices use the same netdev_ops */
397 	return dev->netdev_ops == &ipvlan_netdev_ops;
398 }
399 
400 static int ipvlan_ethtool_get_link_ksettings(struct net_device *dev,
401 					     struct ethtool_link_ksettings *cmd)
402 {
403 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
404 
405 	return __ethtool_get_link_ksettings(ipvlan->phy_dev, cmd);
406 }
407 
408 static void ipvlan_ethtool_get_drvinfo(struct net_device *dev,
409 				       struct ethtool_drvinfo *drvinfo)
410 {
411 	strlcpy(drvinfo->driver, IPVLAN_DRV, sizeof(drvinfo->driver));
412 	strlcpy(drvinfo->version, IPV_DRV_VER, sizeof(drvinfo->version));
413 }
414 
415 static u32 ipvlan_ethtool_get_msglevel(struct net_device *dev)
416 {
417 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
418 
419 	return ipvlan->msg_enable;
420 }
421 
422 static void ipvlan_ethtool_set_msglevel(struct net_device *dev, u32 value)
423 {
424 	struct ipvl_dev *ipvlan = netdev_priv(dev);
425 
426 	ipvlan->msg_enable = value;
427 }
428 
429 static const struct ethtool_ops ipvlan_ethtool_ops = {
430 	.get_link	= ethtool_op_get_link,
431 	.get_link_ksettings	= ipvlan_ethtool_get_link_ksettings,
432 	.get_drvinfo	= ipvlan_ethtool_get_drvinfo,
433 	.get_msglevel	= ipvlan_ethtool_get_msglevel,
434 	.set_msglevel	= ipvlan_ethtool_set_msglevel,
435 };
436 
437 static int ipvlan_nl_changelink(struct net_device *dev,
438 				struct nlattr *tb[], struct nlattr *data[],
439 				struct netlink_ext_ack *extack)
440 {
441 	struct ipvl_dev *ipvlan = netdev_priv(dev);
442 	struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev);
443 	int err = 0;
444 
445 	if (!data)
446 		return 0;
447 	if (!ns_capable(dev_net(ipvlan->phy_dev)->user_ns, CAP_NET_ADMIN))
448 		return -EPERM;
449 
450 	if (data[IFLA_IPVLAN_MODE]) {
451 		u16 nmode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
452 
453 		err = ipvlan_set_port_mode(port, nmode, extack);
454 	}
455 
456 	if (!err && data[IFLA_IPVLAN_FLAGS]) {
457 		u16 flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
458 
459 		if (flags & IPVLAN_F_PRIVATE)
460 			ipvlan_mark_private(port);
461 		else
462 			ipvlan_clear_private(port);
463 
464 		if (flags & IPVLAN_F_VEPA)
465 			ipvlan_mark_vepa(port);
466 		else
467 			ipvlan_clear_vepa(port);
468 	}
469 
470 	return err;
471 }
472 
473 static size_t ipvlan_nl_getsize(const struct net_device *dev)
474 {
475 	return (0
476 		+ nla_total_size(2) /* IFLA_IPVLAN_MODE */
477 		+ nla_total_size(2) /* IFLA_IPVLAN_FLAGS */
478 		);
479 }
480 
481 static int ipvlan_nl_validate(struct nlattr *tb[], struct nlattr *data[],
482 			      struct netlink_ext_ack *extack)
483 {
484 	if (!data)
485 		return 0;
486 
487 	if (data[IFLA_IPVLAN_MODE]) {
488 		u16 mode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
489 
490 		if (mode >= IPVLAN_MODE_MAX)
491 			return -EINVAL;
492 	}
493 	if (data[IFLA_IPVLAN_FLAGS]) {
494 		u16 flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
495 
496 		/* Only two bits are used at this moment. */
497 		if (flags & ~(IPVLAN_F_PRIVATE | IPVLAN_F_VEPA))
498 			return -EINVAL;
499 		/* Also both flags can't be active at the same time. */
500 		if ((flags & (IPVLAN_F_PRIVATE | IPVLAN_F_VEPA)) ==
501 		    (IPVLAN_F_PRIVATE | IPVLAN_F_VEPA))
502 			return -EINVAL;
503 	}
504 
505 	return 0;
506 }
507 
508 static int ipvlan_nl_fillinfo(struct sk_buff *skb,
509 			      const struct net_device *dev)
510 {
511 	struct ipvl_dev *ipvlan = netdev_priv(dev);
512 	struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev);
513 	int ret = -EINVAL;
514 
515 	if (!port)
516 		goto err;
517 
518 	ret = -EMSGSIZE;
519 	if (nla_put_u16(skb, IFLA_IPVLAN_MODE, port->mode))
520 		goto err;
521 	if (nla_put_u16(skb, IFLA_IPVLAN_FLAGS, port->flags))
522 		goto err;
523 
524 	return 0;
525 
526 err:
527 	return ret;
528 }
529 
530 int ipvlan_link_new(struct net *src_net, struct net_device *dev,
531 		    struct nlattr *tb[], struct nlattr *data[],
532 		    struct netlink_ext_ack *extack)
533 {
534 	struct ipvl_dev *ipvlan = netdev_priv(dev);
535 	struct ipvl_port *port;
536 	struct net_device *phy_dev;
537 	int err;
538 	u16 mode = IPVLAN_MODE_L3;
539 
540 	if (!tb[IFLA_LINK])
541 		return -EINVAL;
542 
543 	phy_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
544 	if (!phy_dev)
545 		return -ENODEV;
546 
547 	if (netif_is_ipvlan(phy_dev)) {
548 		struct ipvl_dev *tmp = netdev_priv(phy_dev);
549 
550 		phy_dev = tmp->phy_dev;
551 		if (!ns_capable(dev_net(phy_dev)->user_ns, CAP_NET_ADMIN))
552 			return -EPERM;
553 	} else if (!netif_is_ipvlan_port(phy_dev)) {
554 		/* Exit early if the underlying link is invalid or busy */
555 		if (phy_dev->type != ARPHRD_ETHER ||
556 		    phy_dev->flags & IFF_LOOPBACK) {
557 			netdev_err(phy_dev,
558 				   "Master is either lo or non-ether device\n");
559 			return -EINVAL;
560 		}
561 
562 		if (netdev_is_rx_handler_busy(phy_dev)) {
563 			netdev_err(phy_dev, "Device is already in use.\n");
564 			return -EBUSY;
565 		}
566 	}
567 
568 	ipvlan->phy_dev = phy_dev;
569 	ipvlan->dev = dev;
570 	ipvlan->sfeatures = IPVLAN_FEATURES;
571 	if (!tb[IFLA_MTU])
572 		ipvlan_adjust_mtu(ipvlan, phy_dev);
573 	INIT_LIST_HEAD(&ipvlan->addrs);
574 	spin_lock_init(&ipvlan->addrs_lock);
575 
576 	/* TODO Probably put random address here to be presented to the
577 	 * world but keep using the physical-dev address for the outgoing
578 	 * packets.
579 	 */
580 	memcpy(dev->dev_addr, phy_dev->dev_addr, ETH_ALEN);
581 
582 	dev->priv_flags |= IFF_NO_RX_HANDLER;
583 
584 	err = register_netdevice(dev);
585 	if (err < 0)
586 		return err;
587 
588 	/* ipvlan_init() would have created the port, if required */
589 	port = ipvlan_port_get_rtnl(phy_dev);
590 	ipvlan->port = port;
591 
592 	/* If the port-id base is at the MAX value, then wrap it around and
593 	 * begin from 0x1 again. This may be due to a busy system where lots
594 	 * of slaves are getting created and deleted.
595 	 */
596 	if (port->dev_id_start == 0xFFFE)
597 		port->dev_id_start = 0x1;
598 
599 	/* Since L2 address is shared among all IPvlan slaves including
600 	 * master, use unique 16 bit dev-ids to diffentiate among them.
601 	 * Assign IDs between 0x1 and 0xFFFE (used by the master) to each
602 	 * slave link [see addrconf_ifid_eui48()].
603 	 */
604 	err = ida_simple_get(&port->ida, port->dev_id_start, 0xFFFE,
605 			     GFP_KERNEL);
606 	if (err < 0)
607 		err = ida_simple_get(&port->ida, 0x1, port->dev_id_start,
608 				     GFP_KERNEL);
609 	if (err < 0)
610 		goto unregister_netdev;
611 	dev->dev_id = err;
612 
613 	/* Increment id-base to the next slot for the future assignment */
614 	port->dev_id_start = err + 1;
615 
616 	err = netdev_upper_dev_link(phy_dev, dev, extack);
617 	if (err)
618 		goto remove_ida;
619 
620 	/* Flags are per port and latest update overrides. User has
621 	 * to be consistent in setting it just like the mode attribute.
622 	 */
623 	if (data && data[IFLA_IPVLAN_FLAGS])
624 		port->flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
625 
626 	if (data && data[IFLA_IPVLAN_MODE])
627 		mode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
628 
629 	err = ipvlan_set_port_mode(port, mode, extack);
630 	if (err)
631 		goto unlink_netdev;
632 
633 	list_add_tail_rcu(&ipvlan->pnode, &port->ipvlans);
634 	netif_stacked_transfer_operstate(phy_dev, dev);
635 	return 0;
636 
637 unlink_netdev:
638 	netdev_upper_dev_unlink(phy_dev, dev);
639 remove_ida:
640 	ida_simple_remove(&port->ida, dev->dev_id);
641 unregister_netdev:
642 	unregister_netdevice(dev);
643 	return err;
644 }
645 EXPORT_SYMBOL_GPL(ipvlan_link_new);
646 
647 void ipvlan_link_delete(struct net_device *dev, struct list_head *head)
648 {
649 	struct ipvl_dev *ipvlan = netdev_priv(dev);
650 	struct ipvl_addr *addr, *next;
651 
652 	spin_lock_bh(&ipvlan->addrs_lock);
653 	list_for_each_entry_safe(addr, next, &ipvlan->addrs, anode) {
654 		ipvlan_ht_addr_del(addr);
655 		list_del_rcu(&addr->anode);
656 		kfree_rcu(addr, rcu);
657 	}
658 	spin_unlock_bh(&ipvlan->addrs_lock);
659 
660 	ida_simple_remove(&ipvlan->port->ida, dev->dev_id);
661 	list_del_rcu(&ipvlan->pnode);
662 	unregister_netdevice_queue(dev, head);
663 	netdev_upper_dev_unlink(ipvlan->phy_dev, dev);
664 }
665 EXPORT_SYMBOL_GPL(ipvlan_link_delete);
666 
667 void ipvlan_link_setup(struct net_device *dev)
668 {
669 	ether_setup(dev);
670 
671 	dev->max_mtu = ETH_MAX_MTU;
672 	dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
673 	dev->priv_flags |= IFF_UNICAST_FLT | IFF_NO_QUEUE;
674 	dev->netdev_ops = &ipvlan_netdev_ops;
675 	dev->needs_free_netdev = true;
676 	dev->header_ops = &ipvlan_header_ops;
677 	dev->ethtool_ops = &ipvlan_ethtool_ops;
678 }
679 EXPORT_SYMBOL_GPL(ipvlan_link_setup);
680 
681 static const struct nla_policy ipvlan_nl_policy[IFLA_IPVLAN_MAX + 1] =
682 {
683 	[IFLA_IPVLAN_MODE] = { .type = NLA_U16 },
684 	[IFLA_IPVLAN_FLAGS] = { .type = NLA_U16 },
685 };
686 
687 static struct rtnl_link_ops ipvlan_link_ops = {
688 	.kind		= "ipvlan",
689 	.priv_size	= sizeof(struct ipvl_dev),
690 
691 	.setup		= ipvlan_link_setup,
692 	.newlink	= ipvlan_link_new,
693 	.dellink	= ipvlan_link_delete,
694 };
695 
696 int ipvlan_link_register(struct rtnl_link_ops *ops)
697 {
698 	ops->get_size	= ipvlan_nl_getsize;
699 	ops->policy	= ipvlan_nl_policy;
700 	ops->validate	= ipvlan_nl_validate;
701 	ops->fill_info	= ipvlan_nl_fillinfo;
702 	ops->changelink = ipvlan_nl_changelink;
703 	ops->maxtype	= IFLA_IPVLAN_MAX;
704 	return rtnl_link_register(ops);
705 }
706 EXPORT_SYMBOL_GPL(ipvlan_link_register);
707 
708 static int ipvlan_device_event(struct notifier_block *unused,
709 			       unsigned long event, void *ptr)
710 {
711 	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
712 	struct netdev_notifier_pre_changeaddr_info *prechaddr_info;
713 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
714 	struct ipvl_dev *ipvlan, *next;
715 	struct ipvl_port *port;
716 	LIST_HEAD(lst_kill);
717 	int err;
718 
719 	if (!netif_is_ipvlan_port(dev))
720 		return NOTIFY_DONE;
721 
722 	port = ipvlan_port_get_rtnl(dev);
723 
724 	switch (event) {
725 	case NETDEV_CHANGE:
726 		list_for_each_entry(ipvlan, &port->ipvlans, pnode)
727 			netif_stacked_transfer_operstate(ipvlan->phy_dev,
728 							 ipvlan->dev);
729 		break;
730 
731 	case NETDEV_REGISTER: {
732 		struct net *oldnet, *newnet = dev_net(dev);
733 
734 		oldnet = read_pnet(&port->pnet);
735 		if (net_eq(newnet, oldnet))
736 			break;
737 
738 		write_pnet(&port->pnet, newnet);
739 
740 		ipvlan_migrate_l3s_hook(oldnet, newnet);
741 		break;
742 	}
743 	case NETDEV_UNREGISTER:
744 		if (dev->reg_state != NETREG_UNREGISTERING)
745 			break;
746 
747 		list_for_each_entry_safe(ipvlan, next, &port->ipvlans, pnode)
748 			ipvlan->dev->rtnl_link_ops->dellink(ipvlan->dev,
749 							    &lst_kill);
750 		unregister_netdevice_many(&lst_kill);
751 		break;
752 
753 	case NETDEV_FEAT_CHANGE:
754 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
755 			ipvlan->dev->gso_max_size = dev->gso_max_size;
756 			ipvlan->dev->gso_max_segs = dev->gso_max_segs;
757 			netdev_update_features(ipvlan->dev);
758 		}
759 		break;
760 
761 	case NETDEV_CHANGEMTU:
762 		list_for_each_entry(ipvlan, &port->ipvlans, pnode)
763 			ipvlan_adjust_mtu(ipvlan, dev);
764 		break;
765 
766 	case NETDEV_PRE_CHANGEADDR:
767 		prechaddr_info = ptr;
768 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
769 			err = dev_pre_changeaddr_notify(ipvlan->dev,
770 						    prechaddr_info->dev_addr,
771 						    extack);
772 			if (err)
773 				return notifier_from_errno(err);
774 		}
775 		break;
776 
777 	case NETDEV_CHANGEADDR:
778 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
779 			ether_addr_copy(ipvlan->dev->dev_addr, dev->dev_addr);
780 			call_netdevice_notifiers(NETDEV_CHANGEADDR, ipvlan->dev);
781 		}
782 		break;
783 
784 	case NETDEV_PRE_TYPE_CHANGE:
785 		/* Forbid underlying device to change its type. */
786 		return NOTIFY_BAD;
787 	}
788 	return NOTIFY_DONE;
789 }
790 
791 /* the caller must held the addrs lock */
792 static int ipvlan_add_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
793 {
794 	struct ipvl_addr *addr;
795 
796 	addr = kzalloc(sizeof(struct ipvl_addr), GFP_ATOMIC);
797 	if (!addr)
798 		return -ENOMEM;
799 
800 	addr->master = ipvlan;
801 	if (!is_v6) {
802 		memcpy(&addr->ip4addr, iaddr, sizeof(struct in_addr));
803 		addr->atype = IPVL_IPV4;
804 #if IS_ENABLED(CONFIG_IPV6)
805 	} else {
806 		memcpy(&addr->ip6addr, iaddr, sizeof(struct in6_addr));
807 		addr->atype = IPVL_IPV6;
808 #endif
809 	}
810 
811 	list_add_tail_rcu(&addr->anode, &ipvlan->addrs);
812 
813 	/* If the interface is not up, the address will be added to the hash
814 	 * list by ipvlan_open.
815 	 */
816 	if (netif_running(ipvlan->dev))
817 		ipvlan_ht_addr_add(ipvlan, addr);
818 
819 	return 0;
820 }
821 
822 static void ipvlan_del_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
823 {
824 	struct ipvl_addr *addr;
825 
826 	spin_lock_bh(&ipvlan->addrs_lock);
827 	addr = ipvlan_find_addr(ipvlan, iaddr, is_v6);
828 	if (!addr) {
829 		spin_unlock_bh(&ipvlan->addrs_lock);
830 		return;
831 	}
832 
833 	ipvlan_ht_addr_del(addr);
834 	list_del_rcu(&addr->anode);
835 	spin_unlock_bh(&ipvlan->addrs_lock);
836 	kfree_rcu(addr, rcu);
837 }
838 
839 static bool ipvlan_is_valid_dev(const struct net_device *dev)
840 {
841 	struct ipvl_dev *ipvlan = netdev_priv(dev);
842 
843 	if (!netif_is_ipvlan(dev))
844 		return false;
845 
846 	if (!ipvlan || !ipvlan->port)
847 		return false;
848 
849 	return true;
850 }
851 
852 #if IS_ENABLED(CONFIG_IPV6)
853 static int ipvlan_add_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
854 {
855 	int ret = -EINVAL;
856 
857 	spin_lock_bh(&ipvlan->addrs_lock);
858 	if (ipvlan_addr_busy(ipvlan->port, ip6_addr, true))
859 		netif_err(ipvlan, ifup, ipvlan->dev,
860 			  "Failed to add IPv6=%pI6c addr for %s intf\n",
861 			  ip6_addr, ipvlan->dev->name);
862 	else
863 		ret = ipvlan_add_addr(ipvlan, ip6_addr, true);
864 	spin_unlock_bh(&ipvlan->addrs_lock);
865 	return ret;
866 }
867 
868 static void ipvlan_del_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
869 {
870 	return ipvlan_del_addr(ipvlan, ip6_addr, true);
871 }
872 
873 static int ipvlan_addr6_event(struct notifier_block *unused,
874 			      unsigned long event, void *ptr)
875 {
876 	struct inet6_ifaddr *if6 = (struct inet6_ifaddr *)ptr;
877 	struct net_device *dev = (struct net_device *)if6->idev->dev;
878 	struct ipvl_dev *ipvlan = netdev_priv(dev);
879 
880 	if (!ipvlan_is_valid_dev(dev))
881 		return NOTIFY_DONE;
882 
883 	switch (event) {
884 	case NETDEV_UP:
885 		if (ipvlan_add_addr6(ipvlan, &if6->addr))
886 			return NOTIFY_BAD;
887 		break;
888 
889 	case NETDEV_DOWN:
890 		ipvlan_del_addr6(ipvlan, &if6->addr);
891 		break;
892 	}
893 
894 	return NOTIFY_OK;
895 }
896 
897 static int ipvlan_addr6_validator_event(struct notifier_block *unused,
898 					unsigned long event, void *ptr)
899 {
900 	struct in6_validator_info *i6vi = (struct in6_validator_info *)ptr;
901 	struct net_device *dev = (struct net_device *)i6vi->i6vi_dev->dev;
902 	struct ipvl_dev *ipvlan = netdev_priv(dev);
903 
904 	if (!ipvlan_is_valid_dev(dev))
905 		return NOTIFY_DONE;
906 
907 	switch (event) {
908 	case NETDEV_UP:
909 		if (ipvlan_addr_busy(ipvlan->port, &i6vi->i6vi_addr, true)) {
910 			NL_SET_ERR_MSG(i6vi->extack,
911 				       "Address already assigned to an ipvlan device");
912 			return notifier_from_errno(-EADDRINUSE);
913 		}
914 		break;
915 	}
916 
917 	return NOTIFY_OK;
918 }
919 #endif
920 
921 static int ipvlan_add_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
922 {
923 	int ret = -EINVAL;
924 
925 	spin_lock_bh(&ipvlan->addrs_lock);
926 	if (ipvlan_addr_busy(ipvlan->port, ip4_addr, false))
927 		netif_err(ipvlan, ifup, ipvlan->dev,
928 			  "Failed to add IPv4=%pI4 on %s intf.\n",
929 			  ip4_addr, ipvlan->dev->name);
930 	else
931 		ret = ipvlan_add_addr(ipvlan, ip4_addr, false);
932 	spin_unlock_bh(&ipvlan->addrs_lock);
933 	return ret;
934 }
935 
936 static void ipvlan_del_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
937 {
938 	return ipvlan_del_addr(ipvlan, ip4_addr, false);
939 }
940 
941 static int ipvlan_addr4_event(struct notifier_block *unused,
942 			      unsigned long event, void *ptr)
943 {
944 	struct in_ifaddr *if4 = (struct in_ifaddr *)ptr;
945 	struct net_device *dev = (struct net_device *)if4->ifa_dev->dev;
946 	struct ipvl_dev *ipvlan = netdev_priv(dev);
947 	struct in_addr ip4_addr;
948 
949 	if (!ipvlan_is_valid_dev(dev))
950 		return NOTIFY_DONE;
951 
952 	switch (event) {
953 	case NETDEV_UP:
954 		ip4_addr.s_addr = if4->ifa_address;
955 		if (ipvlan_add_addr4(ipvlan, &ip4_addr))
956 			return NOTIFY_BAD;
957 		break;
958 
959 	case NETDEV_DOWN:
960 		ip4_addr.s_addr = if4->ifa_address;
961 		ipvlan_del_addr4(ipvlan, &ip4_addr);
962 		break;
963 	}
964 
965 	return NOTIFY_OK;
966 }
967 
968 static int ipvlan_addr4_validator_event(struct notifier_block *unused,
969 					unsigned long event, void *ptr)
970 {
971 	struct in_validator_info *ivi = (struct in_validator_info *)ptr;
972 	struct net_device *dev = (struct net_device *)ivi->ivi_dev->dev;
973 	struct ipvl_dev *ipvlan = netdev_priv(dev);
974 
975 	if (!ipvlan_is_valid_dev(dev))
976 		return NOTIFY_DONE;
977 
978 	switch (event) {
979 	case NETDEV_UP:
980 		if (ipvlan_addr_busy(ipvlan->port, &ivi->ivi_addr, false)) {
981 			NL_SET_ERR_MSG(ivi->extack,
982 				       "Address already assigned to an ipvlan device");
983 			return notifier_from_errno(-EADDRINUSE);
984 		}
985 		break;
986 	}
987 
988 	return NOTIFY_OK;
989 }
990 
991 static struct notifier_block ipvlan_addr4_notifier_block __read_mostly = {
992 	.notifier_call = ipvlan_addr4_event,
993 };
994 
995 static struct notifier_block ipvlan_addr4_vtor_notifier_block __read_mostly = {
996 	.notifier_call = ipvlan_addr4_validator_event,
997 };
998 
999 static struct notifier_block ipvlan_notifier_block __read_mostly = {
1000 	.notifier_call = ipvlan_device_event,
1001 };
1002 
1003 #if IS_ENABLED(CONFIG_IPV6)
1004 static struct notifier_block ipvlan_addr6_notifier_block __read_mostly = {
1005 	.notifier_call = ipvlan_addr6_event,
1006 };
1007 
1008 static struct notifier_block ipvlan_addr6_vtor_notifier_block __read_mostly = {
1009 	.notifier_call = ipvlan_addr6_validator_event,
1010 };
1011 #endif
1012 
1013 static int __init ipvlan_init_module(void)
1014 {
1015 	int err;
1016 
1017 	ipvlan_init_secret();
1018 	register_netdevice_notifier(&ipvlan_notifier_block);
1019 #if IS_ENABLED(CONFIG_IPV6)
1020 	register_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1021 	register_inet6addr_validator_notifier(
1022 	    &ipvlan_addr6_vtor_notifier_block);
1023 #endif
1024 	register_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1025 	register_inetaddr_validator_notifier(&ipvlan_addr4_vtor_notifier_block);
1026 
1027 	err = ipvlan_l3s_init();
1028 	if (err < 0)
1029 		goto error;
1030 
1031 	err = ipvlan_link_register(&ipvlan_link_ops);
1032 	if (err < 0) {
1033 		ipvlan_l3s_cleanup();
1034 		goto error;
1035 	}
1036 
1037 	return 0;
1038 error:
1039 	unregister_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1040 	unregister_inetaddr_validator_notifier(
1041 	    &ipvlan_addr4_vtor_notifier_block);
1042 #if IS_ENABLED(CONFIG_IPV6)
1043 	unregister_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1044 	unregister_inet6addr_validator_notifier(
1045 	    &ipvlan_addr6_vtor_notifier_block);
1046 #endif
1047 	unregister_netdevice_notifier(&ipvlan_notifier_block);
1048 	return err;
1049 }
1050 
1051 static void __exit ipvlan_cleanup_module(void)
1052 {
1053 	rtnl_link_unregister(&ipvlan_link_ops);
1054 	ipvlan_l3s_cleanup();
1055 	unregister_netdevice_notifier(&ipvlan_notifier_block);
1056 	unregister_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1057 	unregister_inetaddr_validator_notifier(
1058 	    &ipvlan_addr4_vtor_notifier_block);
1059 #if IS_ENABLED(CONFIG_IPV6)
1060 	unregister_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1061 	unregister_inet6addr_validator_notifier(
1062 	    &ipvlan_addr6_vtor_notifier_block);
1063 #endif
1064 }
1065 
1066 module_init(ipvlan_init_module);
1067 module_exit(ipvlan_cleanup_module);
1068 
1069 MODULE_LICENSE("GPL");
1070 MODULE_AUTHOR("Mahesh Bandewar <maheshb@google.com>");
1071 MODULE_DESCRIPTION("Driver for L3 (IPv6/IPv4) based VLANs");
1072 MODULE_ALIAS_RTNL_LINK("ipvlan");
1073