xref: /linux/drivers/net/vrf.c (revision 9bacbced0e32204deb8b9d011279f9beddd8c2ef)
1 /*
2  * vrf.c: device driver to encapsulate a VRF space
3  *
4  * Copyright (c) 2015 Cumulus Networks. All rights reserved.
5  * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
6  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
7  *
8  * Based on dummy, team and ipvlan drivers
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  */
15 
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/netdevice.h>
19 #include <linux/etherdevice.h>
20 #include <linux/ip.h>
21 #include <linux/init.h>
22 #include <linux/moduleparam.h>
23 #include <linux/netfilter.h>
24 #include <linux/rtnetlink.h>
25 #include <net/rtnetlink.h>
26 #include <linux/u64_stats_sync.h>
27 #include <linux/hashtable.h>
28 
29 #include <linux/inetdevice.h>
30 #include <net/arp.h>
31 #include <net/ip.h>
32 #include <net/ip_fib.h>
33 #include <net/ip6_fib.h>
34 #include <net/ip6_route.h>
35 #include <net/route.h>
36 #include <net/addrconf.h>
37 #include <net/l3mdev.h>
38 #include <net/fib_rules.h>
39 #include <net/netns/generic.h>
40 
41 #define DRV_NAME	"vrf"
42 #define DRV_VERSION	"1.0"
43 
44 #define FIB_RULE_PREF  1000       /* default preference for FIB rules */
45 
46 static unsigned int vrf_net_id;
47 
48 struct net_vrf {
49 	struct rtable __rcu	*rth;
50 	struct rt6_info	__rcu	*rt6;
51 #if IS_ENABLED(CONFIG_IPV6)
52 	struct fib6_table	*fib6_table;
53 #endif
54 	u32                     tb_id;
55 };
56 
57 struct pcpu_dstats {
58 	u64			tx_pkts;
59 	u64			tx_bytes;
60 	u64			tx_drps;
61 	u64			rx_pkts;
62 	u64			rx_bytes;
63 	u64			rx_drps;
64 	struct u64_stats_sync	syncp;
65 };
66 
67 static void vrf_rx_stats(struct net_device *dev, int len)
68 {
69 	struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
70 
71 	u64_stats_update_begin(&dstats->syncp);
72 	dstats->rx_pkts++;
73 	dstats->rx_bytes += len;
74 	u64_stats_update_end(&dstats->syncp);
75 }
76 
77 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
78 {
79 	vrf_dev->stats.tx_errors++;
80 	kfree_skb(skb);
81 }
82 
83 static void vrf_get_stats64(struct net_device *dev,
84 			    struct rtnl_link_stats64 *stats)
85 {
86 	int i;
87 
88 	for_each_possible_cpu(i) {
89 		const struct pcpu_dstats *dstats;
90 		u64 tbytes, tpkts, tdrops, rbytes, rpkts;
91 		unsigned int start;
92 
93 		dstats = per_cpu_ptr(dev->dstats, i);
94 		do {
95 			start = u64_stats_fetch_begin_irq(&dstats->syncp);
96 			tbytes = dstats->tx_bytes;
97 			tpkts = dstats->tx_pkts;
98 			tdrops = dstats->tx_drps;
99 			rbytes = dstats->rx_bytes;
100 			rpkts = dstats->rx_pkts;
101 		} while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
102 		stats->tx_bytes += tbytes;
103 		stats->tx_packets += tpkts;
104 		stats->tx_dropped += tdrops;
105 		stats->rx_bytes += rbytes;
106 		stats->rx_packets += rpkts;
107 	}
108 }
109 
110 /* by default VRF devices do not have a qdisc and are expected
111  * to be created with only a single queue.
112  */
113 static bool qdisc_tx_is_default(const struct net_device *dev)
114 {
115 	struct netdev_queue *txq;
116 	struct Qdisc *qdisc;
117 
118 	if (dev->num_tx_queues > 1)
119 		return false;
120 
121 	txq = netdev_get_tx_queue(dev, 0);
122 	qdisc = rcu_access_pointer(txq->qdisc);
123 
124 	return !qdisc->enqueue;
125 }
126 
127 /* Local traffic destined to local address. Reinsert the packet to rx
128  * path, similar to loopback handling.
129  */
130 static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
131 			  struct dst_entry *dst)
132 {
133 	int len = skb->len;
134 
135 	skb_orphan(skb);
136 
137 	skb_dst_set(skb, dst);
138 
139 	/* set pkt_type to avoid skb hitting packet taps twice -
140 	 * once on Tx and again in Rx processing
141 	 */
142 	skb->pkt_type = PACKET_LOOPBACK;
143 
144 	skb->protocol = eth_type_trans(skb, dev);
145 
146 	if (likely(netif_rx(skb) == NET_RX_SUCCESS))
147 		vrf_rx_stats(dev, len);
148 	else
149 		this_cpu_inc(dev->dstats->rx_drps);
150 
151 	return NETDEV_TX_OK;
152 }
153 
154 #if IS_ENABLED(CONFIG_IPV6)
155 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
156 			     struct sk_buff *skb)
157 {
158 	int err;
159 
160 	err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
161 		      sk, skb, NULL, skb_dst(skb)->dev, dst_output);
162 
163 	if (likely(err == 1))
164 		err = dst_output(net, sk, skb);
165 
166 	return err;
167 }
168 
169 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
170 					   struct net_device *dev)
171 {
172 	const struct ipv6hdr *iph = ipv6_hdr(skb);
173 	struct net *net = dev_net(skb->dev);
174 	struct flowi6 fl6 = {
175 		/* needed to match OIF rule */
176 		.flowi6_oif = dev->ifindex,
177 		.flowi6_iif = LOOPBACK_IFINDEX,
178 		.daddr = iph->daddr,
179 		.saddr = iph->saddr,
180 		.flowlabel = ip6_flowinfo(iph),
181 		.flowi6_mark = skb->mark,
182 		.flowi6_proto = iph->nexthdr,
183 		.flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF,
184 	};
185 	int ret = NET_XMIT_DROP;
186 	struct dst_entry *dst;
187 	struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
188 
189 	dst = ip6_route_output(net, NULL, &fl6);
190 	if (dst == dst_null)
191 		goto err;
192 
193 	skb_dst_drop(skb);
194 
195 	/* if dst.dev is loopback or the VRF device again this is locally
196 	 * originated traffic destined to a local address. Short circuit
197 	 * to Rx path
198 	 */
199 	if (dst->dev == dev)
200 		return vrf_local_xmit(skb, dev, dst);
201 
202 	skb_dst_set(skb, dst);
203 
204 	/* strip the ethernet header added for pass through VRF device */
205 	__skb_pull(skb, skb_network_offset(skb));
206 
207 	ret = vrf_ip6_local_out(net, skb->sk, skb);
208 	if (unlikely(net_xmit_eval(ret)))
209 		dev->stats.tx_errors++;
210 	else
211 		ret = NET_XMIT_SUCCESS;
212 
213 	return ret;
214 err:
215 	vrf_tx_error(dev, skb);
216 	return NET_XMIT_DROP;
217 }
218 #else
219 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
220 					   struct net_device *dev)
221 {
222 	vrf_tx_error(dev, skb);
223 	return NET_XMIT_DROP;
224 }
225 #endif
226 
227 /* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
228 static int vrf_ip_local_out(struct net *net, struct sock *sk,
229 			    struct sk_buff *skb)
230 {
231 	int err;
232 
233 	err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
234 		      skb, NULL, skb_dst(skb)->dev, dst_output);
235 	if (likely(err == 1))
236 		err = dst_output(net, sk, skb);
237 
238 	return err;
239 }
240 
241 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
242 					   struct net_device *vrf_dev)
243 {
244 	struct iphdr *ip4h = ip_hdr(skb);
245 	int ret = NET_XMIT_DROP;
246 	struct flowi4 fl4 = {
247 		/* needed to match OIF rule */
248 		.flowi4_oif = vrf_dev->ifindex,
249 		.flowi4_iif = LOOPBACK_IFINDEX,
250 		.flowi4_tos = RT_TOS(ip4h->tos),
251 		.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF,
252 		.flowi4_proto = ip4h->protocol,
253 		.daddr = ip4h->daddr,
254 		.saddr = ip4h->saddr,
255 	};
256 	struct net *net = dev_net(vrf_dev);
257 	struct rtable *rt;
258 
259 	rt = ip_route_output_flow(net, &fl4, NULL);
260 	if (IS_ERR(rt))
261 		goto err;
262 
263 	skb_dst_drop(skb);
264 
265 	/* if dst.dev is loopback or the VRF device again this is locally
266 	 * originated traffic destined to a local address. Short circuit
267 	 * to Rx path
268 	 */
269 	if (rt->dst.dev == vrf_dev)
270 		return vrf_local_xmit(skb, vrf_dev, &rt->dst);
271 
272 	skb_dst_set(skb, &rt->dst);
273 
274 	/* strip the ethernet header added for pass through VRF device */
275 	__skb_pull(skb, skb_network_offset(skb));
276 
277 	if (!ip4h->saddr) {
278 		ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
279 					       RT_SCOPE_LINK);
280 	}
281 
282 	ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
283 	if (unlikely(net_xmit_eval(ret)))
284 		vrf_dev->stats.tx_errors++;
285 	else
286 		ret = NET_XMIT_SUCCESS;
287 
288 out:
289 	return ret;
290 err:
291 	vrf_tx_error(vrf_dev, skb);
292 	goto out;
293 }
294 
295 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
296 {
297 	switch (skb->protocol) {
298 	case htons(ETH_P_IP):
299 		return vrf_process_v4_outbound(skb, dev);
300 	case htons(ETH_P_IPV6):
301 		return vrf_process_v6_outbound(skb, dev);
302 	default:
303 		vrf_tx_error(dev, skb);
304 		return NET_XMIT_DROP;
305 	}
306 }
307 
308 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
309 {
310 	int len = skb->len;
311 	netdev_tx_t ret = is_ip_tx_frame(skb, dev);
312 
313 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
314 		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
315 
316 		u64_stats_update_begin(&dstats->syncp);
317 		dstats->tx_pkts++;
318 		dstats->tx_bytes += len;
319 		u64_stats_update_end(&dstats->syncp);
320 	} else {
321 		this_cpu_inc(dev->dstats->tx_drps);
322 	}
323 
324 	return ret;
325 }
326 
327 static int vrf_finish_direct(struct net *net, struct sock *sk,
328 			     struct sk_buff *skb)
329 {
330 	struct net_device *vrf_dev = skb->dev;
331 
332 	if (!list_empty(&vrf_dev->ptype_all) &&
333 	    likely(skb_headroom(skb) >= ETH_HLEN)) {
334 		struct ethhdr *eth = skb_push(skb, ETH_HLEN);
335 
336 		ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
337 		eth_zero_addr(eth->h_dest);
338 		eth->h_proto = skb->protocol;
339 
340 		rcu_read_lock_bh();
341 		dev_queue_xmit_nit(skb, vrf_dev);
342 		rcu_read_unlock_bh();
343 
344 		skb_pull(skb, ETH_HLEN);
345 	}
346 
347 	return 1;
348 }
349 
350 #if IS_ENABLED(CONFIG_IPV6)
351 /* modelled after ip6_finish_output2 */
352 static int vrf_finish_output6(struct net *net, struct sock *sk,
353 			      struct sk_buff *skb)
354 {
355 	struct dst_entry *dst = skb_dst(skb);
356 	struct net_device *dev = dst->dev;
357 	struct neighbour *neigh;
358 	struct in6_addr *nexthop;
359 	int ret;
360 
361 	nf_reset(skb);
362 
363 	skb->protocol = htons(ETH_P_IPV6);
364 	skb->dev = dev;
365 
366 	rcu_read_lock_bh();
367 	nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
368 	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
369 	if (unlikely(!neigh))
370 		neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
371 	if (!IS_ERR(neigh)) {
372 		sock_confirm_neigh(skb, neigh);
373 		ret = neigh_output(neigh, skb);
374 		rcu_read_unlock_bh();
375 		return ret;
376 	}
377 	rcu_read_unlock_bh();
378 
379 	IP6_INC_STATS(dev_net(dst->dev),
380 		      ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
381 	kfree_skb(skb);
382 	return -EINVAL;
383 }
384 
385 /* modelled after ip6_output */
386 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
387 {
388 	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
389 			    net, sk, skb, NULL, skb_dst(skb)->dev,
390 			    vrf_finish_output6,
391 			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
392 }
393 
394 /* set dst on skb to send packet to us via dev_xmit path. Allows
395  * packet to go through device based features such as qdisc, netfilter
396  * hooks and packet sockets with skb->dev set to vrf device.
397  */
398 static struct sk_buff *vrf_ip6_out_redirect(struct net_device *vrf_dev,
399 					    struct sk_buff *skb)
400 {
401 	struct net_vrf *vrf = netdev_priv(vrf_dev);
402 	struct dst_entry *dst = NULL;
403 	struct rt6_info *rt6;
404 
405 	rcu_read_lock();
406 
407 	rt6 = rcu_dereference(vrf->rt6);
408 	if (likely(rt6)) {
409 		dst = &rt6->dst;
410 		dst_hold(dst);
411 	}
412 
413 	rcu_read_unlock();
414 
415 	if (unlikely(!dst)) {
416 		vrf_tx_error(vrf_dev, skb);
417 		return NULL;
418 	}
419 
420 	skb_dst_drop(skb);
421 	skb_dst_set(skb, dst);
422 
423 	return skb;
424 }
425 
426 static int vrf_output6_direct(struct net *net, struct sock *sk,
427 			      struct sk_buff *skb)
428 {
429 	skb->protocol = htons(ETH_P_IPV6);
430 
431 	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
432 			    net, sk, skb, NULL, skb->dev,
433 			    vrf_finish_direct,
434 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
435 }
436 
437 static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
438 					  struct sock *sk,
439 					  struct sk_buff *skb)
440 {
441 	struct net *net = dev_net(vrf_dev);
442 	int err;
443 
444 	skb->dev = vrf_dev;
445 
446 	err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk,
447 		      skb, NULL, vrf_dev, vrf_output6_direct);
448 
449 	if (likely(err == 1))
450 		err = vrf_output6_direct(net, sk, skb);
451 
452 	/* reset skb device */
453 	if (likely(err == 1))
454 		nf_reset(skb);
455 	else
456 		skb = NULL;
457 
458 	return skb;
459 }
460 
461 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
462 				   struct sock *sk,
463 				   struct sk_buff *skb)
464 {
465 	/* don't divert link scope packets */
466 	if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
467 		return skb;
468 
469 	if (qdisc_tx_is_default(vrf_dev))
470 		return vrf_ip6_out_direct(vrf_dev, sk, skb);
471 
472 	return vrf_ip6_out_redirect(vrf_dev, skb);
473 }
474 
475 /* holding rtnl */
476 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
477 {
478 	struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
479 	struct net *net = dev_net(dev);
480 	struct dst_entry *dst;
481 
482 	RCU_INIT_POINTER(vrf->rt6, NULL);
483 	synchronize_rcu();
484 
485 	/* move dev in dst's to loopback so this VRF device can be deleted
486 	 * - based on dst_ifdown
487 	 */
488 	if (rt6) {
489 		dst = &rt6->dst;
490 		dev_put(dst->dev);
491 		dst->dev = net->loopback_dev;
492 		dev_hold(dst->dev);
493 		dst_release(dst);
494 	}
495 }
496 
497 static int vrf_rt6_create(struct net_device *dev)
498 {
499 	int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM;
500 	struct net_vrf *vrf = netdev_priv(dev);
501 	struct net *net = dev_net(dev);
502 	struct rt6_info *rt6;
503 	int rc = -ENOMEM;
504 
505 	/* IPv6 can be CONFIG enabled and then disabled runtime */
506 	if (!ipv6_mod_enabled())
507 		return 0;
508 
509 	vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
510 	if (!vrf->fib6_table)
511 		goto out;
512 
513 	/* create a dst for routing packets out a VRF device */
514 	rt6 = ip6_dst_alloc(net, dev, flags);
515 	if (!rt6)
516 		goto out;
517 
518 	rt6->dst.output	= vrf_output6;
519 
520 	rcu_assign_pointer(vrf->rt6, rt6);
521 
522 	rc = 0;
523 out:
524 	return rc;
525 }
526 #else
527 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
528 				   struct sock *sk,
529 				   struct sk_buff *skb)
530 {
531 	return skb;
532 }
533 
534 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
535 {
536 }
537 
538 static int vrf_rt6_create(struct net_device *dev)
539 {
540 	return 0;
541 }
542 #endif
543 
544 /* modelled after ip_finish_output2 */
545 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
546 {
547 	struct dst_entry *dst = skb_dst(skb);
548 	struct rtable *rt = (struct rtable *)dst;
549 	struct net_device *dev = dst->dev;
550 	unsigned int hh_len = LL_RESERVED_SPACE(dev);
551 	struct neighbour *neigh;
552 	u32 nexthop;
553 	int ret = -EINVAL;
554 
555 	nf_reset(skb);
556 
557 	/* Be paranoid, rather than too clever. */
558 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
559 		struct sk_buff *skb2;
560 
561 		skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
562 		if (!skb2) {
563 			ret = -ENOMEM;
564 			goto err;
565 		}
566 		if (skb->sk)
567 			skb_set_owner_w(skb2, skb->sk);
568 
569 		consume_skb(skb);
570 		skb = skb2;
571 	}
572 
573 	rcu_read_lock_bh();
574 
575 	nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
576 	neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
577 	if (unlikely(!neigh))
578 		neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
579 	if (!IS_ERR(neigh)) {
580 		sock_confirm_neigh(skb, neigh);
581 		ret = neigh_output(neigh, skb);
582 		rcu_read_unlock_bh();
583 		return ret;
584 	}
585 
586 	rcu_read_unlock_bh();
587 err:
588 	vrf_tx_error(skb->dev, skb);
589 	return ret;
590 }
591 
592 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
593 {
594 	struct net_device *dev = skb_dst(skb)->dev;
595 
596 	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
597 
598 	skb->dev = dev;
599 	skb->protocol = htons(ETH_P_IP);
600 
601 	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
602 			    net, sk, skb, NULL, dev,
603 			    vrf_finish_output,
604 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
605 }
606 
607 /* set dst on skb to send packet to us via dev_xmit path. Allows
608  * packet to go through device based features such as qdisc, netfilter
609  * hooks and packet sockets with skb->dev set to vrf device.
610  */
611 static struct sk_buff *vrf_ip_out_redirect(struct net_device *vrf_dev,
612 					   struct sk_buff *skb)
613 {
614 	struct net_vrf *vrf = netdev_priv(vrf_dev);
615 	struct dst_entry *dst = NULL;
616 	struct rtable *rth;
617 
618 	rcu_read_lock();
619 
620 	rth = rcu_dereference(vrf->rth);
621 	if (likely(rth)) {
622 		dst = &rth->dst;
623 		dst_hold(dst);
624 	}
625 
626 	rcu_read_unlock();
627 
628 	if (unlikely(!dst)) {
629 		vrf_tx_error(vrf_dev, skb);
630 		return NULL;
631 	}
632 
633 	skb_dst_drop(skb);
634 	skb_dst_set(skb, dst);
635 
636 	return skb;
637 }
638 
639 static int vrf_output_direct(struct net *net, struct sock *sk,
640 			     struct sk_buff *skb)
641 {
642 	skb->protocol = htons(ETH_P_IP);
643 
644 	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
645 			    net, sk, skb, NULL, skb->dev,
646 			    vrf_finish_direct,
647 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
648 }
649 
650 static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
651 					 struct sock *sk,
652 					 struct sk_buff *skb)
653 {
654 	struct net *net = dev_net(vrf_dev);
655 	int err;
656 
657 	skb->dev = vrf_dev;
658 
659 	err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
660 		      skb, NULL, vrf_dev, vrf_output_direct);
661 
662 	if (likely(err == 1))
663 		err = vrf_output_direct(net, sk, skb);
664 
665 	/* reset skb device */
666 	if (likely(err == 1))
667 		nf_reset(skb);
668 	else
669 		skb = NULL;
670 
671 	return skb;
672 }
673 
674 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
675 				  struct sock *sk,
676 				  struct sk_buff *skb)
677 {
678 	/* don't divert multicast or local broadcast */
679 	if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
680 	    ipv4_is_lbcast(ip_hdr(skb)->daddr))
681 		return skb;
682 
683 	if (qdisc_tx_is_default(vrf_dev))
684 		return vrf_ip_out_direct(vrf_dev, sk, skb);
685 
686 	return vrf_ip_out_redirect(vrf_dev, skb);
687 }
688 
689 /* called with rcu lock held */
690 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
691 				  struct sock *sk,
692 				  struct sk_buff *skb,
693 				  u16 proto)
694 {
695 	switch (proto) {
696 	case AF_INET:
697 		return vrf_ip_out(vrf_dev, sk, skb);
698 	case AF_INET6:
699 		return vrf_ip6_out(vrf_dev, sk, skb);
700 	}
701 
702 	return skb;
703 }
704 
705 /* holding rtnl */
706 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
707 {
708 	struct rtable *rth = rtnl_dereference(vrf->rth);
709 	struct net *net = dev_net(dev);
710 	struct dst_entry *dst;
711 
712 	RCU_INIT_POINTER(vrf->rth, NULL);
713 	synchronize_rcu();
714 
715 	/* move dev in dst's to loopback so this VRF device can be deleted
716 	 * - based on dst_ifdown
717 	 */
718 	if (rth) {
719 		dst = &rth->dst;
720 		dev_put(dst->dev);
721 		dst->dev = net->loopback_dev;
722 		dev_hold(dst->dev);
723 		dst_release(dst);
724 	}
725 }
726 
727 static int vrf_rtable_create(struct net_device *dev)
728 {
729 	struct net_vrf *vrf = netdev_priv(dev);
730 	struct rtable *rth;
731 
732 	if (!fib_new_table(dev_net(dev), vrf->tb_id))
733 		return -ENOMEM;
734 
735 	/* create a dst for routing packets out through a VRF device */
736 	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
737 	if (!rth)
738 		return -ENOMEM;
739 
740 	rth->dst.output	= vrf_output;
741 
742 	rcu_assign_pointer(vrf->rth, rth);
743 
744 	return 0;
745 }
746 
747 /**************************** device handling ********************/
748 
749 /* cycle interface to flush neighbor cache and move routes across tables */
750 static void cycle_netdev(struct net_device *dev)
751 {
752 	unsigned int flags = dev->flags;
753 	int ret;
754 
755 	if (!netif_running(dev))
756 		return;
757 
758 	ret = dev_change_flags(dev, flags & ~IFF_UP);
759 	if (ret >= 0)
760 		ret = dev_change_flags(dev, flags);
761 
762 	if (ret < 0) {
763 		netdev_err(dev,
764 			   "Failed to cycle device %s; route tables might be wrong!\n",
765 			   dev->name);
766 	}
767 }
768 
769 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
770 			    struct netlink_ext_ack *extack)
771 {
772 	int ret;
773 
774 	/* do not allow loopback device to be enslaved to a VRF.
775 	 * The vrf device acts as the loopback for the vrf.
776 	 */
777 	if (port_dev == dev_net(dev)->loopback_dev) {
778 		NL_SET_ERR_MSG(extack,
779 			       "Can not enslave loopback device to a VRF");
780 		return -EOPNOTSUPP;
781 	}
782 
783 	port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
784 	ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
785 	if (ret < 0)
786 		goto err;
787 
788 	cycle_netdev(port_dev);
789 
790 	return 0;
791 
792 err:
793 	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
794 	return ret;
795 }
796 
797 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
798 			 struct netlink_ext_ack *extack)
799 {
800 	if (netif_is_l3_master(port_dev)) {
801 		NL_SET_ERR_MSG(extack,
802 			       "Can not enslave an L3 master device to a VRF");
803 		return -EINVAL;
804 	}
805 
806 	if (netif_is_l3_slave(port_dev))
807 		return -EINVAL;
808 
809 	return do_vrf_add_slave(dev, port_dev, extack);
810 }
811 
812 /* inverse of do_vrf_add_slave */
813 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
814 {
815 	netdev_upper_dev_unlink(port_dev, dev);
816 	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
817 
818 	cycle_netdev(port_dev);
819 
820 	return 0;
821 }
822 
823 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
824 {
825 	return do_vrf_del_slave(dev, port_dev);
826 }
827 
828 static void vrf_dev_uninit(struct net_device *dev)
829 {
830 	struct net_vrf *vrf = netdev_priv(dev);
831 
832 	vrf_rtable_release(dev, vrf);
833 	vrf_rt6_release(dev, vrf);
834 
835 	free_percpu(dev->dstats);
836 	dev->dstats = NULL;
837 }
838 
839 static int vrf_dev_init(struct net_device *dev)
840 {
841 	struct net_vrf *vrf = netdev_priv(dev);
842 
843 	dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
844 	if (!dev->dstats)
845 		goto out_nomem;
846 
847 	/* create the default dst which points back to us */
848 	if (vrf_rtable_create(dev) != 0)
849 		goto out_stats;
850 
851 	if (vrf_rt6_create(dev) != 0)
852 		goto out_rth;
853 
854 	dev->flags = IFF_MASTER | IFF_NOARP;
855 
856 	/* MTU is irrelevant for VRF device; set to 64k similar to lo */
857 	dev->mtu = 64 * 1024;
858 
859 	/* similarly, oper state is irrelevant; set to up to avoid confusion */
860 	dev->operstate = IF_OPER_UP;
861 	netdev_lockdep_set_classes(dev);
862 	return 0;
863 
864 out_rth:
865 	vrf_rtable_release(dev, vrf);
866 out_stats:
867 	free_percpu(dev->dstats);
868 	dev->dstats = NULL;
869 out_nomem:
870 	return -ENOMEM;
871 }
872 
873 static const struct net_device_ops vrf_netdev_ops = {
874 	.ndo_init		= vrf_dev_init,
875 	.ndo_uninit		= vrf_dev_uninit,
876 	.ndo_start_xmit		= vrf_xmit,
877 	.ndo_get_stats64	= vrf_get_stats64,
878 	.ndo_add_slave		= vrf_add_slave,
879 	.ndo_del_slave		= vrf_del_slave,
880 };
881 
882 static u32 vrf_fib_table(const struct net_device *dev)
883 {
884 	struct net_vrf *vrf = netdev_priv(dev);
885 
886 	return vrf->tb_id;
887 }
888 
889 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
890 {
891 	kfree_skb(skb);
892 	return 0;
893 }
894 
895 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
896 				      struct sk_buff *skb,
897 				      struct net_device *dev)
898 {
899 	struct net *net = dev_net(dev);
900 
901 	if (nf_hook(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) != 1)
902 		skb = NULL;    /* kfree_skb(skb) handled by nf code */
903 
904 	return skb;
905 }
906 
907 #if IS_ENABLED(CONFIG_IPV6)
908 /* neighbor handling is done with actual device; do not want
909  * to flip skb->dev for those ndisc packets. This really fails
910  * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
911  * a start.
912  */
913 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
914 {
915 	const struct ipv6hdr *iph = ipv6_hdr(skb);
916 	bool rc = false;
917 
918 	if (iph->nexthdr == NEXTHDR_ICMP) {
919 		const struct icmp6hdr *icmph;
920 		struct icmp6hdr _icmph;
921 
922 		icmph = skb_header_pointer(skb, sizeof(*iph),
923 					   sizeof(_icmph), &_icmph);
924 		if (!icmph)
925 			goto out;
926 
927 		switch (icmph->icmp6_type) {
928 		case NDISC_ROUTER_SOLICITATION:
929 		case NDISC_ROUTER_ADVERTISEMENT:
930 		case NDISC_NEIGHBOUR_SOLICITATION:
931 		case NDISC_NEIGHBOUR_ADVERTISEMENT:
932 		case NDISC_REDIRECT:
933 			rc = true;
934 			break;
935 		}
936 	}
937 
938 out:
939 	return rc;
940 }
941 
942 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
943 					     const struct net_device *dev,
944 					     struct flowi6 *fl6,
945 					     int ifindex,
946 					     const struct sk_buff *skb,
947 					     int flags)
948 {
949 	struct net_vrf *vrf = netdev_priv(dev);
950 
951 	return ip6_pol_route(net, vrf->fib6_table, ifindex, fl6, skb, flags);
952 }
953 
954 static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
955 			      int ifindex)
956 {
957 	const struct ipv6hdr *iph = ipv6_hdr(skb);
958 	struct flowi6 fl6 = {
959 		.flowi6_iif     = ifindex,
960 		.flowi6_mark    = skb->mark,
961 		.flowi6_proto   = iph->nexthdr,
962 		.daddr          = iph->daddr,
963 		.saddr          = iph->saddr,
964 		.flowlabel      = ip6_flowinfo(iph),
965 	};
966 	struct net *net = dev_net(vrf_dev);
967 	struct rt6_info *rt6;
968 
969 	rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex, skb,
970 				   RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
971 	if (unlikely(!rt6))
972 		return;
973 
974 	if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
975 		return;
976 
977 	skb_dst_set(skb, &rt6->dst);
978 }
979 
980 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
981 				   struct sk_buff *skb)
982 {
983 	int orig_iif = skb->skb_iif;
984 	bool need_strict;
985 
986 	/* loopback traffic; do not push through packet taps again.
987 	 * Reset pkt_type for upper layers to process skb
988 	 */
989 	if (skb->pkt_type == PACKET_LOOPBACK) {
990 		skb->dev = vrf_dev;
991 		skb->skb_iif = vrf_dev->ifindex;
992 		IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
993 		skb->pkt_type = PACKET_HOST;
994 		goto out;
995 	}
996 
997 	/* if packet is NDISC or addressed to multicast or link-local
998 	 * then keep the ingress interface
999 	 */
1000 	need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
1001 	if (!ipv6_ndisc_frame(skb) && !need_strict) {
1002 		vrf_rx_stats(vrf_dev, skb->len);
1003 		skb->dev = vrf_dev;
1004 		skb->skb_iif = vrf_dev->ifindex;
1005 
1006 		if (!list_empty(&vrf_dev->ptype_all)) {
1007 			skb_push(skb, skb->mac_len);
1008 			dev_queue_xmit_nit(skb, vrf_dev);
1009 			skb_pull(skb, skb->mac_len);
1010 		}
1011 
1012 		IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1013 	}
1014 
1015 	if (need_strict)
1016 		vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1017 
1018 	skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1019 out:
1020 	return skb;
1021 }
1022 
1023 #else
1024 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1025 				   struct sk_buff *skb)
1026 {
1027 	return skb;
1028 }
1029 #endif
1030 
1031 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1032 				  struct sk_buff *skb)
1033 {
1034 	skb->dev = vrf_dev;
1035 	skb->skb_iif = vrf_dev->ifindex;
1036 	IPCB(skb)->flags |= IPSKB_L3SLAVE;
1037 
1038 	if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1039 		goto out;
1040 
1041 	/* loopback traffic; do not push through packet taps again.
1042 	 * Reset pkt_type for upper layers to process skb
1043 	 */
1044 	if (skb->pkt_type == PACKET_LOOPBACK) {
1045 		skb->pkt_type = PACKET_HOST;
1046 		goto out;
1047 	}
1048 
1049 	vrf_rx_stats(vrf_dev, skb->len);
1050 
1051 	if (!list_empty(&vrf_dev->ptype_all)) {
1052 		skb_push(skb, skb->mac_len);
1053 		dev_queue_xmit_nit(skb, vrf_dev);
1054 		skb_pull(skb, skb->mac_len);
1055 	}
1056 
1057 	skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1058 out:
1059 	return skb;
1060 }
1061 
1062 /* called with rcu lock held */
1063 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1064 				  struct sk_buff *skb,
1065 				  u16 proto)
1066 {
1067 	switch (proto) {
1068 	case AF_INET:
1069 		return vrf_ip_rcv(vrf_dev, skb);
1070 	case AF_INET6:
1071 		return vrf_ip6_rcv(vrf_dev, skb);
1072 	}
1073 
1074 	return skb;
1075 }
1076 
1077 #if IS_ENABLED(CONFIG_IPV6)
1078 /* send to link-local or multicast address via interface enslaved to
1079  * VRF device. Force lookup to VRF table without changing flow struct
1080  */
1081 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1082 					      struct flowi6 *fl6)
1083 {
1084 	struct net *net = dev_net(dev);
1085 	int flags = RT6_LOOKUP_F_IFACE;
1086 	struct dst_entry *dst = NULL;
1087 	struct rt6_info *rt;
1088 
1089 	/* VRF device does not have a link-local address and
1090 	 * sending packets to link-local or mcast addresses over
1091 	 * a VRF device does not make sense
1092 	 */
1093 	if (fl6->flowi6_oif == dev->ifindex) {
1094 		dst = &net->ipv6.ip6_null_entry->dst;
1095 		dst_hold(dst);
1096 		return dst;
1097 	}
1098 
1099 	if (!ipv6_addr_any(&fl6->saddr))
1100 		flags |= RT6_LOOKUP_F_HAS_SADDR;
1101 
1102 	rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
1103 	if (rt)
1104 		dst = &rt->dst;
1105 
1106 	return dst;
1107 }
1108 #endif
1109 
1110 static const struct l3mdev_ops vrf_l3mdev_ops = {
1111 	.l3mdev_fib_table	= vrf_fib_table,
1112 	.l3mdev_l3_rcv		= vrf_l3_rcv,
1113 	.l3mdev_l3_out		= vrf_l3_out,
1114 #if IS_ENABLED(CONFIG_IPV6)
1115 	.l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1116 #endif
1117 };
1118 
1119 static void vrf_get_drvinfo(struct net_device *dev,
1120 			    struct ethtool_drvinfo *info)
1121 {
1122 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1123 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1124 }
1125 
1126 static const struct ethtool_ops vrf_ethtool_ops = {
1127 	.get_drvinfo	= vrf_get_drvinfo,
1128 };
1129 
1130 static inline size_t vrf_fib_rule_nl_size(void)
1131 {
1132 	size_t sz;
1133 
1134 	sz  = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1135 	sz += nla_total_size(sizeof(u8));	/* FRA_L3MDEV */
1136 	sz += nla_total_size(sizeof(u32));	/* FRA_PRIORITY */
1137 	sz += nla_total_size(sizeof(u8));       /* FRA_PROTOCOL */
1138 
1139 	return sz;
1140 }
1141 
1142 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1143 {
1144 	struct fib_rule_hdr *frh;
1145 	struct nlmsghdr *nlh;
1146 	struct sk_buff *skb;
1147 	int err;
1148 
1149 	if (family == AF_INET6 && !ipv6_mod_enabled())
1150 		return 0;
1151 
1152 	skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1153 	if (!skb)
1154 		return -ENOMEM;
1155 
1156 	nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1157 	if (!nlh)
1158 		goto nla_put_failure;
1159 
1160 	/* rule only needs to appear once */
1161 	nlh->nlmsg_flags |= NLM_F_EXCL;
1162 
1163 	frh = nlmsg_data(nlh);
1164 	memset(frh, 0, sizeof(*frh));
1165 	frh->family = family;
1166 	frh->action = FR_ACT_TO_TBL;
1167 
1168 	if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
1169 		goto nla_put_failure;
1170 
1171 	if (nla_put_u8(skb, FRA_L3MDEV, 1))
1172 		goto nla_put_failure;
1173 
1174 	if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1175 		goto nla_put_failure;
1176 
1177 	nlmsg_end(skb, nlh);
1178 
1179 	/* fib_nl_{new,del}rule handling looks for net from skb->sk */
1180 	skb->sk = dev_net(dev)->rtnl;
1181 	if (add_it) {
1182 		err = fib_nl_newrule(skb, nlh, NULL);
1183 		if (err == -EEXIST)
1184 			err = 0;
1185 	} else {
1186 		err = fib_nl_delrule(skb, nlh, NULL);
1187 		if (err == -ENOENT)
1188 			err = 0;
1189 	}
1190 	nlmsg_free(skb);
1191 
1192 	return err;
1193 
1194 nla_put_failure:
1195 	nlmsg_free(skb);
1196 
1197 	return -EMSGSIZE;
1198 }
1199 
1200 static int vrf_add_fib_rules(const struct net_device *dev)
1201 {
1202 	int err;
1203 
1204 	err = vrf_fib_rule(dev, AF_INET,  true);
1205 	if (err < 0)
1206 		goto out_err;
1207 
1208 	err = vrf_fib_rule(dev, AF_INET6, true);
1209 	if (err < 0)
1210 		goto ipv6_err;
1211 
1212 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1213 	err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1214 	if (err < 0)
1215 		goto ipmr_err;
1216 #endif
1217 
1218 	return 0;
1219 
1220 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1221 ipmr_err:
1222 	vrf_fib_rule(dev, AF_INET6,  false);
1223 #endif
1224 
1225 ipv6_err:
1226 	vrf_fib_rule(dev, AF_INET,  false);
1227 
1228 out_err:
1229 	netdev_err(dev, "Failed to add FIB rules.\n");
1230 	return err;
1231 }
1232 
1233 static void vrf_setup(struct net_device *dev)
1234 {
1235 	ether_setup(dev);
1236 
1237 	/* Initialize the device structure. */
1238 	dev->netdev_ops = &vrf_netdev_ops;
1239 	dev->l3mdev_ops = &vrf_l3mdev_ops;
1240 	dev->ethtool_ops = &vrf_ethtool_ops;
1241 	dev->needs_free_netdev = true;
1242 
1243 	/* Fill in device structure with ethernet-generic values. */
1244 	eth_hw_addr_random(dev);
1245 
1246 	/* don't acquire vrf device's netif_tx_lock when transmitting */
1247 	dev->features |= NETIF_F_LLTX;
1248 
1249 	/* don't allow vrf devices to change network namespaces. */
1250 	dev->features |= NETIF_F_NETNS_LOCAL;
1251 
1252 	/* does not make sense for a VLAN to be added to a vrf device */
1253 	dev->features   |= NETIF_F_VLAN_CHALLENGED;
1254 
1255 	/* enable offload features */
1256 	dev->features   |= NETIF_F_GSO_SOFTWARE;
1257 	dev->features   |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
1258 	dev->features   |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1259 
1260 	dev->hw_features = dev->features;
1261 	dev->hw_enc_features = dev->features;
1262 
1263 	/* default to no qdisc; user can add if desired */
1264 	dev->priv_flags |= IFF_NO_QUEUE;
1265 }
1266 
1267 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
1268 			struct netlink_ext_ack *extack)
1269 {
1270 	if (tb[IFLA_ADDRESS]) {
1271 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1272 			NL_SET_ERR_MSG(extack, "Invalid hardware address");
1273 			return -EINVAL;
1274 		}
1275 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1276 			NL_SET_ERR_MSG(extack, "Invalid hardware address");
1277 			return -EADDRNOTAVAIL;
1278 		}
1279 	}
1280 	return 0;
1281 }
1282 
1283 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1284 {
1285 	struct net_device *port_dev;
1286 	struct list_head *iter;
1287 
1288 	netdev_for_each_lower_dev(dev, port_dev, iter)
1289 		vrf_del_slave(dev, port_dev);
1290 
1291 	unregister_netdevice_queue(dev, head);
1292 }
1293 
1294 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1295 		       struct nlattr *tb[], struct nlattr *data[],
1296 		       struct netlink_ext_ack *extack)
1297 {
1298 	struct net_vrf *vrf = netdev_priv(dev);
1299 	bool *add_fib_rules;
1300 	struct net *net;
1301 	int err;
1302 
1303 	if (!data || !data[IFLA_VRF_TABLE]) {
1304 		NL_SET_ERR_MSG(extack, "VRF table id is missing");
1305 		return -EINVAL;
1306 	}
1307 
1308 	vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1309 	if (vrf->tb_id == RT_TABLE_UNSPEC) {
1310 		NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
1311 				    "Invalid VRF table id");
1312 		return -EINVAL;
1313 	}
1314 
1315 	dev->priv_flags |= IFF_L3MDEV_MASTER;
1316 
1317 	err = register_netdevice(dev);
1318 	if (err)
1319 		goto out;
1320 
1321 	net = dev_net(dev);
1322 	add_fib_rules = net_generic(net, vrf_net_id);
1323 	if (*add_fib_rules) {
1324 		err = vrf_add_fib_rules(dev);
1325 		if (err) {
1326 			unregister_netdevice(dev);
1327 			goto out;
1328 		}
1329 		*add_fib_rules = false;
1330 	}
1331 
1332 out:
1333 	return err;
1334 }
1335 
1336 static size_t vrf_nl_getsize(const struct net_device *dev)
1337 {
1338 	return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
1339 }
1340 
1341 static int vrf_fillinfo(struct sk_buff *skb,
1342 			const struct net_device *dev)
1343 {
1344 	struct net_vrf *vrf = netdev_priv(dev);
1345 
1346 	return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1347 }
1348 
1349 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1350 				 const struct net_device *slave_dev)
1351 {
1352 	return nla_total_size(sizeof(u32));  /* IFLA_VRF_PORT_TABLE */
1353 }
1354 
1355 static int vrf_fill_slave_info(struct sk_buff *skb,
1356 			       const struct net_device *vrf_dev,
1357 			       const struct net_device *slave_dev)
1358 {
1359 	struct net_vrf *vrf = netdev_priv(vrf_dev);
1360 
1361 	if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1362 		return -EMSGSIZE;
1363 
1364 	return 0;
1365 }
1366 
1367 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1368 	[IFLA_VRF_TABLE] = { .type = NLA_U32 },
1369 };
1370 
1371 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1372 	.kind		= DRV_NAME,
1373 	.priv_size	= sizeof(struct net_vrf),
1374 
1375 	.get_size	= vrf_nl_getsize,
1376 	.policy		= vrf_nl_policy,
1377 	.validate	= vrf_validate,
1378 	.fill_info	= vrf_fillinfo,
1379 
1380 	.get_slave_size  = vrf_get_slave_size,
1381 	.fill_slave_info = vrf_fill_slave_info,
1382 
1383 	.newlink	= vrf_newlink,
1384 	.dellink	= vrf_dellink,
1385 	.setup		= vrf_setup,
1386 	.maxtype	= IFLA_VRF_MAX,
1387 };
1388 
1389 static int vrf_device_event(struct notifier_block *unused,
1390 			    unsigned long event, void *ptr)
1391 {
1392 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1393 
1394 	/* only care about unregister events to drop slave references */
1395 	if (event == NETDEV_UNREGISTER) {
1396 		struct net_device *vrf_dev;
1397 
1398 		if (!netif_is_l3_slave(dev))
1399 			goto out;
1400 
1401 		vrf_dev = netdev_master_upper_dev_get(dev);
1402 		vrf_del_slave(vrf_dev, dev);
1403 	}
1404 out:
1405 	return NOTIFY_DONE;
1406 }
1407 
1408 static struct notifier_block vrf_notifier_block __read_mostly = {
1409 	.notifier_call = vrf_device_event,
1410 };
1411 
1412 /* Initialize per network namespace state */
1413 static int __net_init vrf_netns_init(struct net *net)
1414 {
1415 	bool *add_fib_rules = net_generic(net, vrf_net_id);
1416 
1417 	*add_fib_rules = true;
1418 
1419 	return 0;
1420 }
1421 
1422 static struct pernet_operations vrf_net_ops __net_initdata = {
1423 	.init = vrf_netns_init,
1424 	.id   = &vrf_net_id,
1425 	.size = sizeof(bool),
1426 };
1427 
1428 static int __init vrf_init_module(void)
1429 {
1430 	int rc;
1431 
1432 	register_netdevice_notifier(&vrf_notifier_block);
1433 
1434 	rc = register_pernet_subsys(&vrf_net_ops);
1435 	if (rc < 0)
1436 		goto error;
1437 
1438 	rc = rtnl_link_register(&vrf_link_ops);
1439 	if (rc < 0) {
1440 		unregister_pernet_subsys(&vrf_net_ops);
1441 		goto error;
1442 	}
1443 
1444 	return 0;
1445 
1446 error:
1447 	unregister_netdevice_notifier(&vrf_notifier_block);
1448 	return rc;
1449 }
1450 
1451 module_init(vrf_init_module);
1452 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1453 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1454 MODULE_LICENSE("GPL");
1455 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1456 MODULE_VERSION(DRV_VERSION);
1457