xref: /openbmc/linux/drivers/net/vrf.c (revision 4c1feac58e06270321cc500b85c2d94a11495775)
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 
40 #define RT_FL_TOS(oldflp4) \
41 	((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
42 
43 #define DRV_NAME	"vrf"
44 #define DRV_VERSION	"1.0"
45 
46 #define FIB_RULE_PREF  1000       /* default preference for FIB rules */
47 static bool add_fib_rules = true;
48 
49 struct net_vrf {
50 	struct rtable __rcu	*rth;
51 	struct rtable __rcu	*rth_local;
52 	struct rt6_info	__rcu	*rt6;
53 	struct rt6_info	__rcu	*rt6_local;
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 struct rtnl_link_stats64 *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 	return stats;
109 }
110 
111 /* Local traffic destined to local address. Reinsert the packet to rx
112  * path, similar to loopback handling.
113  */
114 static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
115 			  struct dst_entry *dst)
116 {
117 	int len = skb->len;
118 
119 	skb_orphan(skb);
120 
121 	skb_dst_set(skb, dst);
122 	skb_dst_force(skb);
123 
124 	/* set pkt_type to avoid skb hitting packet taps twice -
125 	 * once on Tx and again in Rx processing
126 	 */
127 	skb->pkt_type = PACKET_LOOPBACK;
128 
129 	skb->protocol = eth_type_trans(skb, dev);
130 
131 	if (likely(netif_rx(skb) == NET_RX_SUCCESS))
132 		vrf_rx_stats(dev, len);
133 	else
134 		this_cpu_inc(dev->dstats->rx_drps);
135 
136 	return NETDEV_TX_OK;
137 }
138 
139 #if IS_ENABLED(CONFIG_IPV6)
140 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
141 			     struct sk_buff *skb)
142 {
143 	int err;
144 
145 	err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
146 		      sk, skb, NULL, skb_dst(skb)->dev, dst_output);
147 
148 	if (likely(err == 1))
149 		err = dst_output(net, sk, skb);
150 
151 	return err;
152 }
153 
154 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
155 					   struct net_device *dev)
156 {
157 	const struct ipv6hdr *iph = ipv6_hdr(skb);
158 	struct net *net = dev_net(skb->dev);
159 	struct flowi6 fl6 = {
160 		/* needed to match OIF rule */
161 		.flowi6_oif = dev->ifindex,
162 		.flowi6_iif = LOOPBACK_IFINDEX,
163 		.daddr = iph->daddr,
164 		.saddr = iph->saddr,
165 		.flowlabel = ip6_flowinfo(iph),
166 		.flowi6_mark = skb->mark,
167 		.flowi6_proto = iph->nexthdr,
168 		.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF,
169 	};
170 	int ret = NET_XMIT_DROP;
171 	struct dst_entry *dst;
172 	struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
173 
174 	dst = ip6_route_output(net, NULL, &fl6);
175 	if (dst == dst_null)
176 		goto err;
177 
178 	skb_dst_drop(skb);
179 
180 	/* if dst.dev is loopback or the VRF device again this is locally
181 	 * originated traffic destined to a local address. Short circuit
182 	 * to Rx path using our local dst
183 	 */
184 	if (dst->dev == net->loopback_dev || dst->dev == dev) {
185 		struct net_vrf *vrf = netdev_priv(dev);
186 		struct rt6_info *rt6_local;
187 
188 		/* release looked up dst and use cached local dst */
189 		dst_release(dst);
190 
191 		rcu_read_lock();
192 
193 		rt6_local = rcu_dereference(vrf->rt6_local);
194 		if (unlikely(!rt6_local)) {
195 			rcu_read_unlock();
196 			goto err;
197 		}
198 
199 		/* Ordering issue: cached local dst is created on newlink
200 		 * before the IPv6 initialization. Using the local dst
201 		 * requires rt6i_idev to be set so make sure it is.
202 		 */
203 		if (unlikely(!rt6_local->rt6i_idev)) {
204 			rt6_local->rt6i_idev = in6_dev_get(dev);
205 			if (!rt6_local->rt6i_idev) {
206 				rcu_read_unlock();
207 				goto err;
208 			}
209 		}
210 
211 		dst = &rt6_local->dst;
212 		dst_hold(dst);
213 
214 		rcu_read_unlock();
215 
216 		return vrf_local_xmit(skb, dev, &rt6_local->dst);
217 	}
218 
219 	skb_dst_set(skb, dst);
220 
221 	/* strip the ethernet header added for pass through VRF device */
222 	__skb_pull(skb, skb_network_offset(skb));
223 
224 	ret = vrf_ip6_local_out(net, skb->sk, skb);
225 	if (unlikely(net_xmit_eval(ret)))
226 		dev->stats.tx_errors++;
227 	else
228 		ret = NET_XMIT_SUCCESS;
229 
230 	return ret;
231 err:
232 	vrf_tx_error(dev, skb);
233 	return NET_XMIT_DROP;
234 }
235 #else
236 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
237 					   struct net_device *dev)
238 {
239 	vrf_tx_error(dev, skb);
240 	return NET_XMIT_DROP;
241 }
242 #endif
243 
244 /* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
245 static int vrf_ip_local_out(struct net *net, struct sock *sk,
246 			    struct sk_buff *skb)
247 {
248 	int err;
249 
250 	err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
251 		      skb, NULL, skb_dst(skb)->dev, dst_output);
252 	if (likely(err == 1))
253 		err = dst_output(net, sk, skb);
254 
255 	return err;
256 }
257 
258 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
259 					   struct net_device *vrf_dev)
260 {
261 	struct iphdr *ip4h = ip_hdr(skb);
262 	int ret = NET_XMIT_DROP;
263 	struct flowi4 fl4 = {
264 		/* needed to match OIF rule */
265 		.flowi4_oif = vrf_dev->ifindex,
266 		.flowi4_iif = LOOPBACK_IFINDEX,
267 		.flowi4_tos = RT_TOS(ip4h->tos),
268 		.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_L3MDEV_SRC |
269 				FLOWI_FLAG_SKIP_NH_OIF,
270 		.daddr = ip4h->daddr,
271 	};
272 	struct net *net = dev_net(vrf_dev);
273 	struct rtable *rt;
274 
275 	rt = ip_route_output_flow(net, &fl4, NULL);
276 	if (IS_ERR(rt))
277 		goto err;
278 
279 	if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
280 		ip_rt_put(rt);
281 		goto err;
282 	}
283 
284 	skb_dst_drop(skb);
285 
286 	/* if dst.dev is loopback or the VRF device again this is locally
287 	 * originated traffic destined to a local address. Short circuit
288 	 * to Rx path using our local dst
289 	 */
290 	if (rt->dst.dev == net->loopback_dev || rt->dst.dev == vrf_dev) {
291 		struct net_vrf *vrf = netdev_priv(vrf_dev);
292 		struct rtable *rth_local;
293 		struct dst_entry *dst = NULL;
294 
295 		ip_rt_put(rt);
296 
297 		rcu_read_lock();
298 
299 		rth_local = rcu_dereference(vrf->rth_local);
300 		if (likely(rth_local)) {
301 			dst = &rth_local->dst;
302 			dst_hold(dst);
303 		}
304 
305 		rcu_read_unlock();
306 
307 		if (unlikely(!dst))
308 			goto err;
309 
310 		return vrf_local_xmit(skb, vrf_dev, dst);
311 	}
312 
313 	skb_dst_set(skb, &rt->dst);
314 
315 	/* strip the ethernet header added for pass through VRF device */
316 	__skb_pull(skb, skb_network_offset(skb));
317 
318 	if (!ip4h->saddr) {
319 		ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
320 					       RT_SCOPE_LINK);
321 	}
322 
323 	ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
324 	if (unlikely(net_xmit_eval(ret)))
325 		vrf_dev->stats.tx_errors++;
326 	else
327 		ret = NET_XMIT_SUCCESS;
328 
329 out:
330 	return ret;
331 err:
332 	vrf_tx_error(vrf_dev, skb);
333 	goto out;
334 }
335 
336 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
337 {
338 	switch (skb->protocol) {
339 	case htons(ETH_P_IP):
340 		return vrf_process_v4_outbound(skb, dev);
341 	case htons(ETH_P_IPV6):
342 		return vrf_process_v6_outbound(skb, dev);
343 	default:
344 		vrf_tx_error(dev, skb);
345 		return NET_XMIT_DROP;
346 	}
347 }
348 
349 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
350 {
351 	netdev_tx_t ret = is_ip_tx_frame(skb, dev);
352 
353 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
354 		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
355 
356 		u64_stats_update_begin(&dstats->syncp);
357 		dstats->tx_pkts++;
358 		dstats->tx_bytes += skb->len;
359 		u64_stats_update_end(&dstats->syncp);
360 	} else {
361 		this_cpu_inc(dev->dstats->tx_drps);
362 	}
363 
364 	return ret;
365 }
366 
367 #if IS_ENABLED(CONFIG_IPV6)
368 /* modelled after ip6_finish_output2 */
369 static int vrf_finish_output6(struct net *net, struct sock *sk,
370 			      struct sk_buff *skb)
371 {
372 	struct dst_entry *dst = skb_dst(skb);
373 	struct net_device *dev = dst->dev;
374 	struct neighbour *neigh;
375 	struct in6_addr *nexthop;
376 	int ret;
377 
378 	skb->protocol = htons(ETH_P_IPV6);
379 	skb->dev = dev;
380 
381 	rcu_read_lock_bh();
382 	nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
383 	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
384 	if (unlikely(!neigh))
385 		neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
386 	if (!IS_ERR(neigh)) {
387 		ret = dst_neigh_output(dst, neigh, skb);
388 		rcu_read_unlock_bh();
389 		return ret;
390 	}
391 	rcu_read_unlock_bh();
392 
393 	IP6_INC_STATS(dev_net(dst->dev),
394 		      ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
395 	kfree_skb(skb);
396 	return -EINVAL;
397 }
398 
399 /* modelled after ip6_output */
400 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
401 {
402 	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
403 			    net, sk, skb, NULL, skb_dst(skb)->dev,
404 			    vrf_finish_output6,
405 			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
406 }
407 
408 /* set dst on skb to send packet to us via dev_xmit path. Allows
409  * packet to go through device based features such as qdisc, netfilter
410  * hooks and packet sockets with skb->dev set to vrf device.
411  */
412 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
413 				   struct sock *sk,
414 				   struct sk_buff *skb)
415 {
416 	struct net_vrf *vrf = netdev_priv(vrf_dev);
417 	struct dst_entry *dst = NULL;
418 	struct rt6_info *rt6;
419 
420 	/* don't divert link scope packets */
421 	if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
422 		return skb;
423 
424 	rcu_read_lock();
425 
426 	rt6 = rcu_dereference(vrf->rt6);
427 	if (likely(rt6)) {
428 		dst = &rt6->dst;
429 		dst_hold(dst);
430 	}
431 
432 	rcu_read_unlock();
433 
434 	if (unlikely(!dst)) {
435 		vrf_tx_error(vrf_dev, skb);
436 		return NULL;
437 	}
438 
439 	skb_dst_drop(skb);
440 	skb_dst_set(skb, dst);
441 
442 	return skb;
443 }
444 
445 /* holding rtnl */
446 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
447 {
448 	struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
449 	struct rt6_info *rt6_local = rtnl_dereference(vrf->rt6_local);
450 	struct net *net = dev_net(dev);
451 	struct dst_entry *dst;
452 
453 	RCU_INIT_POINTER(vrf->rt6, NULL);
454 	RCU_INIT_POINTER(vrf->rt6_local, NULL);
455 	synchronize_rcu();
456 
457 	/* move dev in dst's to loopback so this VRF device can be deleted
458 	 * - based on dst_ifdown
459 	 */
460 	if (rt6) {
461 		dst = &rt6->dst;
462 		dev_put(dst->dev);
463 		dst->dev = net->loopback_dev;
464 		dev_hold(dst->dev);
465 		dst_release(dst);
466 	}
467 
468 	if (rt6_local) {
469 		if (rt6_local->rt6i_idev)
470 			in6_dev_put(rt6_local->rt6i_idev);
471 
472 		dst = &rt6_local->dst;
473 		dev_put(dst->dev);
474 		dst->dev = net->loopback_dev;
475 		dev_hold(dst->dev);
476 		dst_release(dst);
477 	}
478 }
479 
480 static int vrf_rt6_create(struct net_device *dev)
481 {
482 	int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE;
483 	struct net_vrf *vrf = netdev_priv(dev);
484 	struct net *net = dev_net(dev);
485 	struct fib6_table *rt6i_table;
486 	struct rt6_info *rt6, *rt6_local;
487 	int rc = -ENOMEM;
488 
489 	/* IPv6 can be CONFIG enabled and then disabled runtime */
490 	if (!ipv6_mod_enabled())
491 		return 0;
492 
493 	rt6i_table = fib6_new_table(net, vrf->tb_id);
494 	if (!rt6i_table)
495 		goto out;
496 
497 	/* create a dst for routing packets out a VRF device */
498 	rt6 = ip6_dst_alloc(net, dev, flags);
499 	if (!rt6)
500 		goto out;
501 
502 	dst_hold(&rt6->dst);
503 
504 	rt6->rt6i_table = rt6i_table;
505 	rt6->dst.output	= vrf_output6;
506 
507 	/* create a dst for local routing - packets sent locally
508 	 * to local address via the VRF device as a loopback
509 	 */
510 	rt6_local = ip6_dst_alloc(net, dev, flags);
511 	if (!rt6_local) {
512 		dst_release(&rt6->dst);
513 		goto out;
514 	}
515 
516 	dst_hold(&rt6_local->dst);
517 
518 	rt6_local->rt6i_idev  = in6_dev_get(dev);
519 	rt6_local->rt6i_flags = RTF_UP | RTF_NONEXTHOP | RTF_LOCAL;
520 	rt6_local->rt6i_table = rt6i_table;
521 	rt6_local->dst.input  = ip6_input;
522 
523 	rcu_assign_pointer(vrf->rt6, rt6);
524 	rcu_assign_pointer(vrf->rt6_local, rt6_local);
525 
526 	rc = 0;
527 out:
528 	return rc;
529 }
530 #else
531 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
532 				   struct sock *sk,
533 				   struct sk_buff *skb)
534 {
535 	return skb;
536 }
537 
538 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
539 {
540 }
541 
542 static int vrf_rt6_create(struct net_device *dev)
543 {
544 	return 0;
545 }
546 #endif
547 
548 /* modelled after ip_finish_output2 */
549 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
550 {
551 	struct dst_entry *dst = skb_dst(skb);
552 	struct rtable *rt = (struct rtable *)dst;
553 	struct net_device *dev = dst->dev;
554 	unsigned int hh_len = LL_RESERVED_SPACE(dev);
555 	struct neighbour *neigh;
556 	u32 nexthop;
557 	int ret = -EINVAL;
558 
559 	/* Be paranoid, rather than too clever. */
560 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
561 		struct sk_buff *skb2;
562 
563 		skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
564 		if (!skb2) {
565 			ret = -ENOMEM;
566 			goto err;
567 		}
568 		if (skb->sk)
569 			skb_set_owner_w(skb2, skb->sk);
570 
571 		consume_skb(skb);
572 		skb = skb2;
573 	}
574 
575 	rcu_read_lock_bh();
576 
577 	nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
578 	neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
579 	if (unlikely(!neigh))
580 		neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
581 	if (!IS_ERR(neigh))
582 		ret = dst_neigh_output(dst, neigh, skb);
583 
584 	rcu_read_unlock_bh();
585 err:
586 	if (unlikely(ret < 0))
587 		vrf_tx_error(skb->dev, skb);
588 	return ret;
589 }
590 
591 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
592 {
593 	struct net_device *dev = skb_dst(skb)->dev;
594 
595 	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
596 
597 	skb->dev = dev;
598 	skb->protocol = htons(ETH_P_IP);
599 
600 	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
601 			    net, sk, skb, NULL, dev,
602 			    vrf_finish_output,
603 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
604 }
605 
606 /* set dst on skb to send packet to us via dev_xmit path. Allows
607  * packet to go through device based features such as qdisc, netfilter
608  * hooks and packet sockets with skb->dev set to vrf device.
609  */
610 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
611 				  struct sock *sk,
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 /* called with rcu lock held */
640 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
641 				  struct sock *sk,
642 				  struct sk_buff *skb,
643 				  u16 proto)
644 {
645 	switch (proto) {
646 	case AF_INET:
647 		return vrf_ip_out(vrf_dev, sk, skb);
648 	case AF_INET6:
649 		return vrf_ip6_out(vrf_dev, sk, skb);
650 	}
651 
652 	return skb;
653 }
654 
655 /* holding rtnl */
656 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
657 {
658 	struct rtable *rth = rtnl_dereference(vrf->rth);
659 	struct rtable *rth_local = rtnl_dereference(vrf->rth_local);
660 	struct net *net = dev_net(dev);
661 	struct dst_entry *dst;
662 
663 	RCU_INIT_POINTER(vrf->rth, NULL);
664 	RCU_INIT_POINTER(vrf->rth_local, NULL);
665 	synchronize_rcu();
666 
667 	/* move dev in dst's to loopback so this VRF device can be deleted
668 	 * - based on dst_ifdown
669 	 */
670 	if (rth) {
671 		dst = &rth->dst;
672 		dev_put(dst->dev);
673 		dst->dev = net->loopback_dev;
674 		dev_hold(dst->dev);
675 		dst_release(dst);
676 	}
677 
678 	if (rth_local) {
679 		dst = &rth_local->dst;
680 		dev_put(dst->dev);
681 		dst->dev = net->loopback_dev;
682 		dev_hold(dst->dev);
683 		dst_release(dst);
684 	}
685 }
686 
687 static int vrf_rtable_create(struct net_device *dev)
688 {
689 	struct net_vrf *vrf = netdev_priv(dev);
690 	struct rtable *rth, *rth_local;
691 
692 	if (!fib_new_table(dev_net(dev), vrf->tb_id))
693 		return -ENOMEM;
694 
695 	/* create a dst for routing packets out through a VRF device */
696 	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
697 	if (!rth)
698 		return -ENOMEM;
699 
700 	/* create a dst for local ingress routing - packets sent locally
701 	 * to local address via the VRF device as a loopback
702 	 */
703 	rth_local = rt_dst_alloc(dev, RTCF_LOCAL, RTN_LOCAL, 1, 1, 0);
704 	if (!rth_local) {
705 		dst_release(&rth->dst);
706 		return -ENOMEM;
707 	}
708 
709 	rth->dst.output	= vrf_output;
710 	rth->rt_table_id = vrf->tb_id;
711 
712 	rth_local->rt_table_id = vrf->tb_id;
713 
714 	rcu_assign_pointer(vrf->rth, rth);
715 	rcu_assign_pointer(vrf->rth_local, rth_local);
716 
717 	return 0;
718 }
719 
720 /**************************** device handling ********************/
721 
722 /* cycle interface to flush neighbor cache and move routes across tables */
723 static void cycle_netdev(struct net_device *dev)
724 {
725 	unsigned int flags = dev->flags;
726 	int ret;
727 
728 	if (!netif_running(dev))
729 		return;
730 
731 	ret = dev_change_flags(dev, flags & ~IFF_UP);
732 	if (ret >= 0)
733 		ret = dev_change_flags(dev, flags);
734 
735 	if (ret < 0) {
736 		netdev_err(dev,
737 			   "Failed to cycle device %s; route tables might be wrong!\n",
738 			   dev->name);
739 	}
740 }
741 
742 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
743 {
744 	int ret;
745 
746 	ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL);
747 	if (ret < 0)
748 		return ret;
749 
750 	port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
751 	cycle_netdev(port_dev);
752 
753 	return 0;
754 }
755 
756 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
757 {
758 	if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
759 		return -EINVAL;
760 
761 	return do_vrf_add_slave(dev, port_dev);
762 }
763 
764 /* inverse of do_vrf_add_slave */
765 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
766 {
767 	netdev_upper_dev_unlink(port_dev, dev);
768 	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
769 
770 	cycle_netdev(port_dev);
771 
772 	return 0;
773 }
774 
775 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
776 {
777 	return do_vrf_del_slave(dev, port_dev);
778 }
779 
780 static void vrf_dev_uninit(struct net_device *dev)
781 {
782 	struct net_vrf *vrf = netdev_priv(dev);
783 	struct net_device *port_dev;
784 	struct list_head *iter;
785 
786 	vrf_rtable_release(dev, vrf);
787 	vrf_rt6_release(dev, vrf);
788 
789 	netdev_for_each_lower_dev(dev, port_dev, iter)
790 		vrf_del_slave(dev, port_dev);
791 
792 	free_percpu(dev->dstats);
793 	dev->dstats = NULL;
794 }
795 
796 static int vrf_dev_init(struct net_device *dev)
797 {
798 	struct net_vrf *vrf = netdev_priv(dev);
799 
800 	dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
801 	if (!dev->dstats)
802 		goto out_nomem;
803 
804 	/* create the default dst which points back to us */
805 	if (vrf_rtable_create(dev) != 0)
806 		goto out_stats;
807 
808 	if (vrf_rt6_create(dev) != 0)
809 		goto out_rth;
810 
811 	dev->flags = IFF_MASTER | IFF_NOARP;
812 
813 	/* MTU is irrelevant for VRF device; set to 64k similar to lo */
814 	dev->mtu = 64 * 1024;
815 
816 	/* similarly, oper state is irrelevant; set to up to avoid confusion */
817 	dev->operstate = IF_OPER_UP;
818 	netdev_lockdep_set_classes(dev);
819 	return 0;
820 
821 out_rth:
822 	vrf_rtable_release(dev, vrf);
823 out_stats:
824 	free_percpu(dev->dstats);
825 	dev->dstats = NULL;
826 out_nomem:
827 	return -ENOMEM;
828 }
829 
830 static const struct net_device_ops vrf_netdev_ops = {
831 	.ndo_init		= vrf_dev_init,
832 	.ndo_uninit		= vrf_dev_uninit,
833 	.ndo_start_xmit		= vrf_xmit,
834 	.ndo_get_stats64	= vrf_get_stats64,
835 	.ndo_add_slave		= vrf_add_slave,
836 	.ndo_del_slave		= vrf_del_slave,
837 };
838 
839 static u32 vrf_fib_table(const struct net_device *dev)
840 {
841 	struct net_vrf *vrf = netdev_priv(dev);
842 
843 	return vrf->tb_id;
844 }
845 
846 static struct rtable *vrf_get_rtable(const struct net_device *dev,
847 				     const struct flowi4 *fl4)
848 {
849 	struct rtable *rth = NULL;
850 
851 	if (!(fl4->flowi4_flags & FLOWI_FLAG_L3MDEV_SRC)) {
852 		struct net_vrf *vrf = netdev_priv(dev);
853 
854 		rcu_read_lock();
855 
856 		rth = rcu_dereference(vrf->rth);
857 		if (likely(rth))
858 			dst_hold(&rth->dst);
859 
860 		rcu_read_unlock();
861 	}
862 
863 	return rth;
864 }
865 
866 /* called under rcu_read_lock */
867 static int vrf_get_saddr(struct net_device *dev, struct flowi4 *fl4)
868 {
869 	struct fib_result res = { .tclassid = 0 };
870 	struct net *net = dev_net(dev);
871 	u32 orig_tos = fl4->flowi4_tos;
872 	u8 flags = fl4->flowi4_flags;
873 	u8 scope = fl4->flowi4_scope;
874 	u8 tos = RT_FL_TOS(fl4);
875 	int rc;
876 
877 	if (unlikely(!fl4->daddr))
878 		return 0;
879 
880 	fl4->flowi4_flags |= FLOWI_FLAG_SKIP_NH_OIF;
881 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
882 	/* make sure oif is set to VRF device for lookup */
883 	fl4->flowi4_oif = dev->ifindex;
884 	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
885 	fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
886 			     RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
887 
888 	rc = fib_lookup(net, fl4, &res, 0);
889 	if (!rc) {
890 		if (res.type == RTN_LOCAL)
891 			fl4->saddr = res.fi->fib_prefsrc ? : fl4->daddr;
892 		else
893 			fib_select_path(net, &res, fl4, -1);
894 	}
895 
896 	fl4->flowi4_flags = flags;
897 	fl4->flowi4_tos = orig_tos;
898 	fl4->flowi4_scope = scope;
899 
900 	return rc;
901 }
902 
903 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
904 {
905 	return 0;
906 }
907 
908 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
909 				      struct sk_buff *skb,
910 				      struct net_device *dev)
911 {
912 	struct net *net = dev_net(dev);
913 
914 	nf_reset(skb);
915 
916 	if (NF_HOOK(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) < 0)
917 		skb = NULL;    /* kfree_skb(skb) handled by nf code */
918 
919 	return skb;
920 }
921 
922 #if IS_ENABLED(CONFIG_IPV6)
923 /* neighbor handling is done with actual device; do not want
924  * to flip skb->dev for those ndisc packets. This really fails
925  * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
926  * a start.
927  */
928 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
929 {
930 	const struct ipv6hdr *iph = ipv6_hdr(skb);
931 	bool rc = false;
932 
933 	if (iph->nexthdr == NEXTHDR_ICMP) {
934 		const struct icmp6hdr *icmph;
935 		struct icmp6hdr _icmph;
936 
937 		icmph = skb_header_pointer(skb, sizeof(*iph),
938 					   sizeof(_icmph), &_icmph);
939 		if (!icmph)
940 			goto out;
941 
942 		switch (icmph->icmp6_type) {
943 		case NDISC_ROUTER_SOLICITATION:
944 		case NDISC_ROUTER_ADVERTISEMENT:
945 		case NDISC_NEIGHBOUR_SOLICITATION:
946 		case NDISC_NEIGHBOUR_ADVERTISEMENT:
947 		case NDISC_REDIRECT:
948 			rc = true;
949 			break;
950 		}
951 	}
952 
953 out:
954 	return rc;
955 }
956 
957 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
958 					     const struct net_device *dev,
959 					     struct flowi6 *fl6,
960 					     int ifindex,
961 					     int flags)
962 {
963 	struct net_vrf *vrf = netdev_priv(dev);
964 	struct fib6_table *table = NULL;
965 	struct rt6_info *rt6;
966 
967 	rcu_read_lock();
968 
969 	/* fib6_table does not have a refcnt and can not be freed */
970 	rt6 = rcu_dereference(vrf->rt6);
971 	if (likely(rt6))
972 		table = rt6->rt6i_table;
973 
974 	rcu_read_unlock();
975 
976 	if (!table)
977 		return NULL;
978 
979 	return ip6_pol_route(net, table, ifindex, fl6, flags);
980 }
981 
982 static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
983 			      int ifindex)
984 {
985 	const struct ipv6hdr *iph = ipv6_hdr(skb);
986 	struct flowi6 fl6 = {
987 		.daddr          = iph->daddr,
988 		.saddr          = iph->saddr,
989 		.flowlabel      = ip6_flowinfo(iph),
990 		.flowi6_mark    = skb->mark,
991 		.flowi6_proto   = iph->nexthdr,
992 		.flowi6_iif     = ifindex,
993 	};
994 	struct net *net = dev_net(vrf_dev);
995 	struct rt6_info *rt6;
996 
997 	rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex,
998 				   RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
999 	if (unlikely(!rt6))
1000 		return;
1001 
1002 	if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
1003 		return;
1004 
1005 	skb_dst_set(skb, &rt6->dst);
1006 }
1007 
1008 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1009 				   struct sk_buff *skb)
1010 {
1011 	int orig_iif = skb->skb_iif;
1012 	bool need_strict;
1013 
1014 	/* loopback traffic; do not push through packet taps again.
1015 	 * Reset pkt_type for upper layers to process skb
1016 	 */
1017 	if (skb->pkt_type == PACKET_LOOPBACK) {
1018 		skb->dev = vrf_dev;
1019 		skb->skb_iif = vrf_dev->ifindex;
1020 		skb->pkt_type = PACKET_HOST;
1021 		goto out;
1022 	}
1023 
1024 	/* if packet is NDISC or addressed to multicast or link-local
1025 	 * then keep the ingress interface
1026 	 */
1027 	need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
1028 	if (!ipv6_ndisc_frame(skb) && !need_strict) {
1029 		skb->dev = vrf_dev;
1030 		skb->skb_iif = vrf_dev->ifindex;
1031 
1032 		skb_push(skb, skb->mac_len);
1033 		dev_queue_xmit_nit(skb, vrf_dev);
1034 		skb_pull(skb, skb->mac_len);
1035 
1036 		IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1037 	}
1038 
1039 	if (need_strict)
1040 		vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1041 
1042 	skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1043 out:
1044 	return skb;
1045 }
1046 
1047 #else
1048 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1049 				   struct sk_buff *skb)
1050 {
1051 	return skb;
1052 }
1053 #endif
1054 
1055 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1056 				  struct sk_buff *skb)
1057 {
1058 	skb->dev = vrf_dev;
1059 	skb->skb_iif = vrf_dev->ifindex;
1060 
1061 	/* loopback traffic; do not push through packet taps again.
1062 	 * Reset pkt_type for upper layers to process skb
1063 	 */
1064 	if (skb->pkt_type == PACKET_LOOPBACK) {
1065 		skb->pkt_type = PACKET_HOST;
1066 		goto out;
1067 	}
1068 
1069 	skb_push(skb, skb->mac_len);
1070 	dev_queue_xmit_nit(skb, vrf_dev);
1071 	skb_pull(skb, skb->mac_len);
1072 
1073 	skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1074 out:
1075 	return skb;
1076 }
1077 
1078 /* called with rcu lock held */
1079 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1080 				  struct sk_buff *skb,
1081 				  u16 proto)
1082 {
1083 	switch (proto) {
1084 	case AF_INET:
1085 		return vrf_ip_rcv(vrf_dev, skb);
1086 	case AF_INET6:
1087 		return vrf_ip6_rcv(vrf_dev, skb);
1088 	}
1089 
1090 	return skb;
1091 }
1092 
1093 #if IS_ENABLED(CONFIG_IPV6)
1094 /* send to link-local or multicast address via interface enslaved to
1095  * VRF device. Force lookup to VRF table without changing flow struct
1096  */
1097 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1098 					      struct flowi6 *fl6)
1099 {
1100 	struct net *net = dev_net(dev);
1101 	int flags = RT6_LOOKUP_F_IFACE;
1102 	struct dst_entry *dst = NULL;
1103 	struct rt6_info *rt;
1104 
1105 	/* VRF device does not have a link-local address and
1106 	 * sending packets to link-local or mcast addresses over
1107 	 * a VRF device does not make sense
1108 	 */
1109 	if (fl6->flowi6_oif == dev->ifindex) {
1110 		dst = &net->ipv6.ip6_null_entry->dst;
1111 		dst_hold(dst);
1112 		return dst;
1113 	}
1114 
1115 	if (!ipv6_addr_any(&fl6->saddr))
1116 		flags |= RT6_LOOKUP_F_HAS_SADDR;
1117 
1118 	rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, flags);
1119 	if (rt)
1120 		dst = &rt->dst;
1121 
1122 	return dst;
1123 }
1124 
1125 /* called under rcu_read_lock */
1126 static int vrf_get_saddr6(struct net_device *dev, const struct sock *sk,
1127 			  struct flowi6 *fl6)
1128 {
1129 	struct net *net = dev_net(dev);
1130 	struct dst_entry *dst;
1131 	struct rt6_info *rt;
1132 	int err;
1133 
1134 	if (rt6_need_strict(&fl6->daddr)) {
1135 		rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif,
1136 					  RT6_LOOKUP_F_IFACE);
1137 		if (unlikely(!rt))
1138 			return 0;
1139 
1140 		dst = &rt->dst;
1141 	} else {
1142 		__u8 flags = fl6->flowi6_flags;
1143 
1144 		fl6->flowi6_flags |= FLOWI_FLAG_L3MDEV_SRC;
1145 		fl6->flowi6_flags |= FLOWI_FLAG_SKIP_NH_OIF;
1146 
1147 		dst = ip6_route_output(net, sk, fl6);
1148 		rt = (struct rt6_info *)dst;
1149 
1150 		fl6->flowi6_flags = flags;
1151 	}
1152 
1153 	err = dst->error;
1154 	if (!err) {
1155 		err = ip6_route_get_saddr(net, rt, &fl6->daddr,
1156 					  sk ? inet6_sk(sk)->srcprefs : 0,
1157 					  &fl6->saddr);
1158 	}
1159 
1160 	dst_release(dst);
1161 
1162 	return err;
1163 }
1164 #endif
1165 
1166 static const struct l3mdev_ops vrf_l3mdev_ops = {
1167 	.l3mdev_fib_table	= vrf_fib_table,
1168 	.l3mdev_get_rtable	= vrf_get_rtable,
1169 	.l3mdev_get_saddr	= vrf_get_saddr,
1170 	.l3mdev_l3_rcv		= vrf_l3_rcv,
1171 	.l3mdev_l3_out		= vrf_l3_out,
1172 #if IS_ENABLED(CONFIG_IPV6)
1173 	.l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1174 	.l3mdev_get_saddr6	= vrf_get_saddr6,
1175 #endif
1176 };
1177 
1178 static void vrf_get_drvinfo(struct net_device *dev,
1179 			    struct ethtool_drvinfo *info)
1180 {
1181 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1182 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1183 }
1184 
1185 static const struct ethtool_ops vrf_ethtool_ops = {
1186 	.get_drvinfo	= vrf_get_drvinfo,
1187 };
1188 
1189 static inline size_t vrf_fib_rule_nl_size(void)
1190 {
1191 	size_t sz;
1192 
1193 	sz  = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1194 	sz += nla_total_size(sizeof(u8));	/* FRA_L3MDEV */
1195 	sz += nla_total_size(sizeof(u32));	/* FRA_PRIORITY */
1196 
1197 	return sz;
1198 }
1199 
1200 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1201 {
1202 	struct fib_rule_hdr *frh;
1203 	struct nlmsghdr *nlh;
1204 	struct sk_buff *skb;
1205 	int err;
1206 
1207 	if (family == AF_INET6 && !ipv6_mod_enabled())
1208 		return 0;
1209 
1210 	skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1211 	if (!skb)
1212 		return -ENOMEM;
1213 
1214 	nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1215 	if (!nlh)
1216 		goto nla_put_failure;
1217 
1218 	/* rule only needs to appear once */
1219 	nlh->nlmsg_flags &= NLM_F_EXCL;
1220 
1221 	frh = nlmsg_data(nlh);
1222 	memset(frh, 0, sizeof(*frh));
1223 	frh->family = family;
1224 	frh->action = FR_ACT_TO_TBL;
1225 
1226 	if (nla_put_u32(skb, FRA_L3MDEV, 1))
1227 		goto nla_put_failure;
1228 
1229 	if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1230 		goto nla_put_failure;
1231 
1232 	nlmsg_end(skb, nlh);
1233 
1234 	/* fib_nl_{new,del}rule handling looks for net from skb->sk */
1235 	skb->sk = dev_net(dev)->rtnl;
1236 	if (add_it) {
1237 		err = fib_nl_newrule(skb, nlh);
1238 		if (err == -EEXIST)
1239 			err = 0;
1240 	} else {
1241 		err = fib_nl_delrule(skb, nlh);
1242 		if (err == -ENOENT)
1243 			err = 0;
1244 	}
1245 	nlmsg_free(skb);
1246 
1247 	return err;
1248 
1249 nla_put_failure:
1250 	nlmsg_free(skb);
1251 
1252 	return -EMSGSIZE;
1253 }
1254 
1255 static int vrf_add_fib_rules(const struct net_device *dev)
1256 {
1257 	int err;
1258 
1259 	err = vrf_fib_rule(dev, AF_INET,  true);
1260 	if (err < 0)
1261 		goto out_err;
1262 
1263 	err = vrf_fib_rule(dev, AF_INET6, true);
1264 	if (err < 0)
1265 		goto ipv6_err;
1266 
1267 	return 0;
1268 
1269 ipv6_err:
1270 	vrf_fib_rule(dev, AF_INET,  false);
1271 
1272 out_err:
1273 	netdev_err(dev, "Failed to add FIB rules.\n");
1274 	return err;
1275 }
1276 
1277 static void vrf_setup(struct net_device *dev)
1278 {
1279 	ether_setup(dev);
1280 
1281 	/* Initialize the device structure. */
1282 	dev->netdev_ops = &vrf_netdev_ops;
1283 	dev->l3mdev_ops = &vrf_l3mdev_ops;
1284 	dev->ethtool_ops = &vrf_ethtool_ops;
1285 	dev->destructor = free_netdev;
1286 
1287 	/* Fill in device structure with ethernet-generic values. */
1288 	eth_hw_addr_random(dev);
1289 
1290 	/* don't acquire vrf device's netif_tx_lock when transmitting */
1291 	dev->features |= NETIF_F_LLTX;
1292 
1293 	/* don't allow vrf devices to change network namespaces. */
1294 	dev->features |= NETIF_F_NETNS_LOCAL;
1295 
1296 	/* does not make sense for a VLAN to be added to a vrf device */
1297 	dev->features   |= NETIF_F_VLAN_CHALLENGED;
1298 
1299 	/* enable offload features */
1300 	dev->features   |= NETIF_F_GSO_SOFTWARE;
1301 	dev->features   |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM;
1302 	dev->features   |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1303 
1304 	dev->hw_features = dev->features;
1305 	dev->hw_enc_features = dev->features;
1306 
1307 	/* default to no qdisc; user can add if desired */
1308 	dev->priv_flags |= IFF_NO_QUEUE;
1309 }
1310 
1311 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
1312 {
1313 	if (tb[IFLA_ADDRESS]) {
1314 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1315 			return -EINVAL;
1316 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1317 			return -EADDRNOTAVAIL;
1318 	}
1319 	return 0;
1320 }
1321 
1322 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1323 {
1324 	unregister_netdevice_queue(dev, head);
1325 }
1326 
1327 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1328 		       struct nlattr *tb[], struct nlattr *data[])
1329 {
1330 	struct net_vrf *vrf = netdev_priv(dev);
1331 	int err;
1332 
1333 	if (!data || !data[IFLA_VRF_TABLE])
1334 		return -EINVAL;
1335 
1336 	vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1337 
1338 	dev->priv_flags |= IFF_L3MDEV_MASTER;
1339 
1340 	err = register_netdevice(dev);
1341 	if (err)
1342 		goto out;
1343 
1344 	if (add_fib_rules) {
1345 		err = vrf_add_fib_rules(dev);
1346 		if (err) {
1347 			unregister_netdevice(dev);
1348 			goto out;
1349 		}
1350 		add_fib_rules = false;
1351 	}
1352 
1353 out:
1354 	return err;
1355 }
1356 
1357 static size_t vrf_nl_getsize(const struct net_device *dev)
1358 {
1359 	return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
1360 }
1361 
1362 static int vrf_fillinfo(struct sk_buff *skb,
1363 			const struct net_device *dev)
1364 {
1365 	struct net_vrf *vrf = netdev_priv(dev);
1366 
1367 	return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1368 }
1369 
1370 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1371 				 const struct net_device *slave_dev)
1372 {
1373 	return nla_total_size(sizeof(u32));  /* IFLA_VRF_PORT_TABLE */
1374 }
1375 
1376 static int vrf_fill_slave_info(struct sk_buff *skb,
1377 			       const struct net_device *vrf_dev,
1378 			       const struct net_device *slave_dev)
1379 {
1380 	struct net_vrf *vrf = netdev_priv(vrf_dev);
1381 
1382 	if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1383 		return -EMSGSIZE;
1384 
1385 	return 0;
1386 }
1387 
1388 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1389 	[IFLA_VRF_TABLE] = { .type = NLA_U32 },
1390 };
1391 
1392 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1393 	.kind		= DRV_NAME,
1394 	.priv_size	= sizeof(struct net_vrf),
1395 
1396 	.get_size	= vrf_nl_getsize,
1397 	.policy		= vrf_nl_policy,
1398 	.validate	= vrf_validate,
1399 	.fill_info	= vrf_fillinfo,
1400 
1401 	.get_slave_size  = vrf_get_slave_size,
1402 	.fill_slave_info = vrf_fill_slave_info,
1403 
1404 	.newlink	= vrf_newlink,
1405 	.dellink	= vrf_dellink,
1406 	.setup		= vrf_setup,
1407 	.maxtype	= IFLA_VRF_MAX,
1408 };
1409 
1410 static int vrf_device_event(struct notifier_block *unused,
1411 			    unsigned long event, void *ptr)
1412 {
1413 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1414 
1415 	/* only care about unregister events to drop slave references */
1416 	if (event == NETDEV_UNREGISTER) {
1417 		struct net_device *vrf_dev;
1418 
1419 		if (!netif_is_l3_slave(dev))
1420 			goto out;
1421 
1422 		vrf_dev = netdev_master_upper_dev_get(dev);
1423 		vrf_del_slave(vrf_dev, dev);
1424 	}
1425 out:
1426 	return NOTIFY_DONE;
1427 }
1428 
1429 static struct notifier_block vrf_notifier_block __read_mostly = {
1430 	.notifier_call = vrf_device_event,
1431 };
1432 
1433 static int __init vrf_init_module(void)
1434 {
1435 	int rc;
1436 
1437 	register_netdevice_notifier(&vrf_notifier_block);
1438 
1439 	rc = rtnl_link_register(&vrf_link_ops);
1440 	if (rc < 0)
1441 		goto error;
1442 
1443 	return 0;
1444 
1445 error:
1446 	unregister_netdevice_notifier(&vrf_notifier_block);
1447 	return rc;
1448 }
1449 
1450 module_init(vrf_init_module);
1451 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1452 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1453 MODULE_LICENSE("GPL");
1454 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1455 MODULE_VERSION(DRV_VERSION);
1456