xref: /linux/drivers/net/vrf.c (revision 1ff23beebdd315fe4d16070c08c065e89d7debb3)
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 
39 #define RT_FL_TOS(oldflp4) \
40 	((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
41 
42 #define DRV_NAME	"vrf"
43 #define DRV_VERSION	"1.0"
44 
45 #define vrf_master_get_rcu(dev) \
46 	((struct net_device *)rcu_dereference(dev->rx_handler_data))
47 
48 struct net_vrf {
49 	struct rtable           *rth;
50 	struct rt6_info		*rt6;
51 	u32                     tb_id;
52 };
53 
54 struct pcpu_dstats {
55 	u64			tx_pkts;
56 	u64			tx_bytes;
57 	u64			tx_drps;
58 	u64			rx_pkts;
59 	u64			rx_bytes;
60 	struct u64_stats_sync	syncp;
61 };
62 
63 /* neighbor handling is done with actual device; do not want
64  * to flip skb->dev for those ndisc packets. This really fails
65  * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
66  * a start.
67  */
68 #if IS_ENABLED(CONFIG_IPV6)
69 static bool check_ipv6_frame(const struct sk_buff *skb)
70 {
71 	const struct ipv6hdr *ipv6h;
72 	struct ipv6hdr _ipv6h;
73 	bool rc = true;
74 
75 	ipv6h = skb_header_pointer(skb, 0, sizeof(_ipv6h), &_ipv6h);
76 	if (!ipv6h)
77 		goto out;
78 
79 	if (ipv6h->nexthdr == NEXTHDR_ICMP) {
80 		const struct icmp6hdr *icmph;
81 		struct icmp6hdr _icmph;
82 
83 		icmph = skb_header_pointer(skb, sizeof(_ipv6h),
84 					   sizeof(_icmph), &_icmph);
85 		if (!icmph)
86 			goto out;
87 
88 		switch (icmph->icmp6_type) {
89 		case NDISC_ROUTER_SOLICITATION:
90 		case NDISC_ROUTER_ADVERTISEMENT:
91 		case NDISC_NEIGHBOUR_SOLICITATION:
92 		case NDISC_NEIGHBOUR_ADVERTISEMENT:
93 		case NDISC_REDIRECT:
94 			rc = false;
95 			break;
96 		}
97 	}
98 
99 out:
100 	return rc;
101 }
102 #else
103 static bool check_ipv6_frame(const struct sk_buff *skb)
104 {
105 	return false;
106 }
107 #endif
108 
109 static bool is_ip_rx_frame(struct sk_buff *skb)
110 {
111 	switch (skb->protocol) {
112 	case htons(ETH_P_IP):
113 		return true;
114 	case htons(ETH_P_IPV6):
115 		return check_ipv6_frame(skb);
116 	}
117 	return false;
118 }
119 
120 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
121 {
122 	vrf_dev->stats.tx_errors++;
123 	kfree_skb(skb);
124 }
125 
126 /* note: already called with rcu_read_lock */
127 static rx_handler_result_t vrf_handle_frame(struct sk_buff **pskb)
128 {
129 	struct sk_buff *skb = *pskb;
130 
131 	if (is_ip_rx_frame(skb)) {
132 		struct net_device *dev = vrf_master_get_rcu(skb->dev);
133 		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
134 
135 		u64_stats_update_begin(&dstats->syncp);
136 		dstats->rx_pkts++;
137 		dstats->rx_bytes += skb->len;
138 		u64_stats_update_end(&dstats->syncp);
139 
140 		skb->dev = dev;
141 
142 		return RX_HANDLER_ANOTHER;
143 	}
144 	return RX_HANDLER_PASS;
145 }
146 
147 static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
148 						 struct rtnl_link_stats64 *stats)
149 {
150 	int i;
151 
152 	for_each_possible_cpu(i) {
153 		const struct pcpu_dstats *dstats;
154 		u64 tbytes, tpkts, tdrops, rbytes, rpkts;
155 		unsigned int start;
156 
157 		dstats = per_cpu_ptr(dev->dstats, i);
158 		do {
159 			start = u64_stats_fetch_begin_irq(&dstats->syncp);
160 			tbytes = dstats->tx_bytes;
161 			tpkts = dstats->tx_pkts;
162 			tdrops = dstats->tx_drps;
163 			rbytes = dstats->rx_bytes;
164 			rpkts = dstats->rx_pkts;
165 		} while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
166 		stats->tx_bytes += tbytes;
167 		stats->tx_packets += tpkts;
168 		stats->tx_dropped += tdrops;
169 		stats->rx_bytes += rbytes;
170 		stats->rx_packets += rpkts;
171 	}
172 	return stats;
173 }
174 
175 #if IS_ENABLED(CONFIG_IPV6)
176 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
177 					   struct net_device *dev)
178 {
179 	const struct ipv6hdr *iph = ipv6_hdr(skb);
180 	struct net *net = dev_net(skb->dev);
181 	struct flowi6 fl6 = {
182 		/* needed to match OIF rule */
183 		.flowi6_oif = dev->ifindex,
184 		.flowi6_iif = LOOPBACK_IFINDEX,
185 		.daddr = iph->daddr,
186 		.saddr = iph->saddr,
187 		.flowlabel = ip6_flowinfo(iph),
188 		.flowi6_mark = skb->mark,
189 		.flowi6_proto = iph->nexthdr,
190 		.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF,
191 	};
192 	int ret = NET_XMIT_DROP;
193 	struct dst_entry *dst;
194 	struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
195 
196 	dst = ip6_route_output(net, NULL, &fl6);
197 	if (dst == dst_null)
198 		goto err;
199 
200 	skb_dst_drop(skb);
201 	skb_dst_set(skb, dst);
202 
203 	ret = ip6_local_out(net, skb->sk, skb);
204 	if (unlikely(net_xmit_eval(ret)))
205 		dev->stats.tx_errors++;
206 	else
207 		ret = NET_XMIT_SUCCESS;
208 
209 	return ret;
210 err:
211 	vrf_tx_error(dev, skb);
212 	return NET_XMIT_DROP;
213 }
214 #else
215 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
216 					   struct net_device *dev)
217 {
218 	vrf_tx_error(dev, skb);
219 	return NET_XMIT_DROP;
220 }
221 #endif
222 
223 static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4,
224 			    struct net_device *vrf_dev)
225 {
226 	struct rtable *rt;
227 	int err = 1;
228 
229 	rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL);
230 	if (IS_ERR(rt))
231 		goto out;
232 
233 	/* TO-DO: what about broadcast ? */
234 	if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
235 		ip_rt_put(rt);
236 		goto out;
237 	}
238 
239 	skb_dst_drop(skb);
240 	skb_dst_set(skb, &rt->dst);
241 	err = 0;
242 out:
243 	return err;
244 }
245 
246 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
247 					   struct net_device *vrf_dev)
248 {
249 	struct iphdr *ip4h = ip_hdr(skb);
250 	int ret = NET_XMIT_DROP;
251 	struct flowi4 fl4 = {
252 		/* needed to match OIF rule */
253 		.flowi4_oif = vrf_dev->ifindex,
254 		.flowi4_iif = LOOPBACK_IFINDEX,
255 		.flowi4_tos = RT_TOS(ip4h->tos),
256 		.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_L3MDEV_SRC |
257 				FLOWI_FLAG_SKIP_NH_OIF,
258 		.daddr = ip4h->daddr,
259 	};
260 
261 	if (vrf_send_v4_prep(skb, &fl4, vrf_dev))
262 		goto err;
263 
264 	if (!ip4h->saddr) {
265 		ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
266 					       RT_SCOPE_LINK);
267 	}
268 
269 	ret = ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
270 	if (unlikely(net_xmit_eval(ret)))
271 		vrf_dev->stats.tx_errors++;
272 	else
273 		ret = NET_XMIT_SUCCESS;
274 
275 out:
276 	return ret;
277 err:
278 	vrf_tx_error(vrf_dev, skb);
279 	goto out;
280 }
281 
282 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
283 {
284 	/* strip the ethernet header added for pass through VRF device */
285 	__skb_pull(skb, skb_network_offset(skb));
286 
287 	switch (skb->protocol) {
288 	case htons(ETH_P_IP):
289 		return vrf_process_v4_outbound(skb, dev);
290 	case htons(ETH_P_IPV6):
291 		return vrf_process_v6_outbound(skb, dev);
292 	default:
293 		vrf_tx_error(dev, skb);
294 		return NET_XMIT_DROP;
295 	}
296 }
297 
298 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
299 {
300 	netdev_tx_t ret = is_ip_tx_frame(skb, dev);
301 
302 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
303 		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
304 
305 		u64_stats_update_begin(&dstats->syncp);
306 		dstats->tx_pkts++;
307 		dstats->tx_bytes += skb->len;
308 		u64_stats_update_end(&dstats->syncp);
309 	} else {
310 		this_cpu_inc(dev->dstats->tx_drps);
311 	}
312 
313 	return ret;
314 }
315 
316 #if IS_ENABLED(CONFIG_IPV6)
317 /* modelled after ip6_finish_output2 */
318 static int vrf_finish_output6(struct net *net, struct sock *sk,
319 			      struct sk_buff *skb)
320 {
321 	struct dst_entry *dst = skb_dst(skb);
322 	struct net_device *dev = dst->dev;
323 	struct neighbour *neigh;
324 	struct in6_addr *nexthop;
325 	int ret;
326 
327 	skb->protocol = htons(ETH_P_IPV6);
328 	skb->dev = dev;
329 
330 	rcu_read_lock_bh();
331 	nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
332 	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
333 	if (unlikely(!neigh))
334 		neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
335 	if (!IS_ERR(neigh)) {
336 		ret = dst_neigh_output(dst, neigh, skb);
337 		rcu_read_unlock_bh();
338 		return ret;
339 	}
340 	rcu_read_unlock_bh();
341 
342 	IP6_INC_STATS(dev_net(dst->dev),
343 		      ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
344 	kfree_skb(skb);
345 	return -EINVAL;
346 }
347 
348 /* modelled after ip6_output */
349 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
350 {
351 	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
352 			    net, sk, skb, NULL, skb_dst(skb)->dev,
353 			    vrf_finish_output6,
354 			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
355 }
356 
357 static void vrf_rt6_release(struct net_vrf *vrf)
358 {
359 	dst_release(&vrf->rt6->dst);
360 	vrf->rt6 = NULL;
361 }
362 
363 static int vrf_rt6_create(struct net_device *dev)
364 {
365 	struct net_vrf *vrf = netdev_priv(dev);
366 	struct net *net = dev_net(dev);
367 	struct fib6_table *rt6i_table;
368 	struct rt6_info *rt6;
369 	int rc = -ENOMEM;
370 
371 	rt6i_table = fib6_new_table(net, vrf->tb_id);
372 	if (!rt6i_table)
373 		goto out;
374 
375 	rt6 = ip6_dst_alloc(net, dev,
376 			    DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE);
377 	if (!rt6)
378 		goto out;
379 
380 	dst_hold(&rt6->dst);
381 
382 	rt6->rt6i_table = rt6i_table;
383 	rt6->dst.output	= vrf_output6;
384 	vrf->rt6 = rt6;
385 	rc = 0;
386 out:
387 	return rc;
388 }
389 #else
390 static void vrf_rt6_release(struct net_vrf *vrf)
391 {
392 }
393 
394 static int vrf_rt6_create(struct net_device *dev)
395 {
396 	return 0;
397 }
398 #endif
399 
400 /* modelled after ip_finish_output2 */
401 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
402 {
403 	struct dst_entry *dst = skb_dst(skb);
404 	struct rtable *rt = (struct rtable *)dst;
405 	struct net_device *dev = dst->dev;
406 	unsigned int hh_len = LL_RESERVED_SPACE(dev);
407 	struct neighbour *neigh;
408 	u32 nexthop;
409 	int ret = -EINVAL;
410 
411 	/* Be paranoid, rather than too clever. */
412 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
413 		struct sk_buff *skb2;
414 
415 		skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
416 		if (!skb2) {
417 			ret = -ENOMEM;
418 			goto err;
419 		}
420 		if (skb->sk)
421 			skb_set_owner_w(skb2, skb->sk);
422 
423 		consume_skb(skb);
424 		skb = skb2;
425 	}
426 
427 	rcu_read_lock_bh();
428 
429 	nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
430 	neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
431 	if (unlikely(!neigh))
432 		neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
433 	if (!IS_ERR(neigh))
434 		ret = dst_neigh_output(dst, neigh, skb);
435 
436 	rcu_read_unlock_bh();
437 err:
438 	if (unlikely(ret < 0))
439 		vrf_tx_error(skb->dev, skb);
440 	return ret;
441 }
442 
443 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
444 {
445 	struct net_device *dev = skb_dst(skb)->dev;
446 
447 	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
448 
449 	skb->dev = dev;
450 	skb->protocol = htons(ETH_P_IP);
451 
452 	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
453 			    net, sk, skb, NULL, dev,
454 			    vrf_finish_output,
455 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
456 }
457 
458 static void vrf_rtable_release(struct net_vrf *vrf)
459 {
460 	struct dst_entry *dst = (struct dst_entry *)vrf->rth;
461 
462 	dst_release(dst);
463 	vrf->rth = NULL;
464 }
465 
466 static struct rtable *vrf_rtable_create(struct net_device *dev)
467 {
468 	struct net_vrf *vrf = netdev_priv(dev);
469 	struct rtable *rth;
470 
471 	if (!fib_new_table(dev_net(dev), vrf->tb_id))
472 		return NULL;
473 
474 	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
475 	if (rth) {
476 		rth->dst.output	= vrf_output;
477 		rth->rt_table_id = vrf->tb_id;
478 	}
479 
480 	return rth;
481 }
482 
483 /**************************** device handling ********************/
484 
485 /* cycle interface to flush neighbor cache and move routes across tables */
486 static void cycle_netdev(struct net_device *dev)
487 {
488 	unsigned int flags = dev->flags;
489 	int ret;
490 
491 	if (!netif_running(dev))
492 		return;
493 
494 	ret = dev_change_flags(dev, flags & ~IFF_UP);
495 	if (ret >= 0)
496 		ret = dev_change_flags(dev, flags);
497 
498 	if (ret < 0) {
499 		netdev_err(dev,
500 			   "Failed to cycle device %s; route tables might be wrong!\n",
501 			   dev->name);
502 	}
503 }
504 
505 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
506 {
507 	int ret;
508 
509 	/* register the packet handler for slave ports */
510 	ret = netdev_rx_handler_register(port_dev, vrf_handle_frame, dev);
511 	if (ret) {
512 		netdev_err(port_dev,
513 			   "Device %s failed to register rx_handler\n",
514 			   port_dev->name);
515 		goto out_fail;
516 	}
517 
518 	ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL);
519 	if (ret < 0)
520 		goto out_unregister;
521 
522 	port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
523 	cycle_netdev(port_dev);
524 
525 	return 0;
526 
527 out_unregister:
528 	netdev_rx_handler_unregister(port_dev);
529 out_fail:
530 	return ret;
531 }
532 
533 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
534 {
535 	if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
536 		return -EINVAL;
537 
538 	return do_vrf_add_slave(dev, port_dev);
539 }
540 
541 /* inverse of do_vrf_add_slave */
542 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
543 {
544 	netdev_upper_dev_unlink(port_dev, dev);
545 	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
546 
547 	netdev_rx_handler_unregister(port_dev);
548 
549 	cycle_netdev(port_dev);
550 
551 	return 0;
552 }
553 
554 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
555 {
556 	return do_vrf_del_slave(dev, port_dev);
557 }
558 
559 static void vrf_dev_uninit(struct net_device *dev)
560 {
561 	struct net_vrf *vrf = netdev_priv(dev);
562 	struct net_device *port_dev;
563 	struct list_head *iter;
564 
565 	vrf_rtable_release(vrf);
566 	vrf_rt6_release(vrf);
567 
568 	netdev_for_each_lower_dev(dev, port_dev, iter)
569 		vrf_del_slave(dev, port_dev);
570 
571 	free_percpu(dev->dstats);
572 	dev->dstats = NULL;
573 }
574 
575 static int vrf_dev_init(struct net_device *dev)
576 {
577 	struct net_vrf *vrf = netdev_priv(dev);
578 
579 	dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
580 	if (!dev->dstats)
581 		goto out_nomem;
582 
583 	/* create the default dst which points back to us */
584 	vrf->rth = vrf_rtable_create(dev);
585 	if (!vrf->rth)
586 		goto out_stats;
587 
588 	if (vrf_rt6_create(dev) != 0)
589 		goto out_rth;
590 
591 	dev->flags = IFF_MASTER | IFF_NOARP;
592 
593 	return 0;
594 
595 out_rth:
596 	vrf_rtable_release(vrf);
597 out_stats:
598 	free_percpu(dev->dstats);
599 	dev->dstats = NULL;
600 out_nomem:
601 	return -ENOMEM;
602 }
603 
604 static const struct net_device_ops vrf_netdev_ops = {
605 	.ndo_init		= vrf_dev_init,
606 	.ndo_uninit		= vrf_dev_uninit,
607 	.ndo_start_xmit		= vrf_xmit,
608 	.ndo_get_stats64	= vrf_get_stats64,
609 	.ndo_add_slave		= vrf_add_slave,
610 	.ndo_del_slave		= vrf_del_slave,
611 };
612 
613 static u32 vrf_fib_table(const struct net_device *dev)
614 {
615 	struct net_vrf *vrf = netdev_priv(dev);
616 
617 	return vrf->tb_id;
618 }
619 
620 static struct rtable *vrf_get_rtable(const struct net_device *dev,
621 				     const struct flowi4 *fl4)
622 {
623 	struct rtable *rth = NULL;
624 
625 	if (!(fl4->flowi4_flags & FLOWI_FLAG_L3MDEV_SRC)) {
626 		struct net_vrf *vrf = netdev_priv(dev);
627 
628 		rth = vrf->rth;
629 		dst_hold(&rth->dst);
630 	}
631 
632 	return rth;
633 }
634 
635 /* called under rcu_read_lock */
636 static int vrf_get_saddr(struct net_device *dev, struct flowi4 *fl4)
637 {
638 	struct fib_result res = { .tclassid = 0 };
639 	struct net *net = dev_net(dev);
640 	u32 orig_tos = fl4->flowi4_tos;
641 	u8 flags = fl4->flowi4_flags;
642 	u8 scope = fl4->flowi4_scope;
643 	u8 tos = RT_FL_TOS(fl4);
644 	int rc;
645 
646 	if (unlikely(!fl4->daddr))
647 		return 0;
648 
649 	fl4->flowi4_flags |= FLOWI_FLAG_SKIP_NH_OIF;
650 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
651 	/* make sure oif is set to VRF device for lookup */
652 	fl4->flowi4_oif = dev->ifindex;
653 	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
654 	fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
655 			     RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
656 
657 	rc = fib_lookup(net, fl4, &res, 0);
658 	if (!rc) {
659 		if (res.type == RTN_LOCAL)
660 			fl4->saddr = res.fi->fib_prefsrc ? : fl4->daddr;
661 		else
662 			fib_select_path(net, &res, fl4, -1);
663 	}
664 
665 	fl4->flowi4_flags = flags;
666 	fl4->flowi4_tos = orig_tos;
667 	fl4->flowi4_scope = scope;
668 
669 	return rc;
670 }
671 
672 #if IS_ENABLED(CONFIG_IPV6)
673 static struct dst_entry *vrf_get_rt6_dst(const struct net_device *dev,
674 					 const struct flowi6 *fl6)
675 {
676 	struct rt6_info *rt = NULL;
677 
678 	if (!(fl6->flowi6_flags & FLOWI_FLAG_L3MDEV_SRC)) {
679 		struct net_vrf *vrf = netdev_priv(dev);
680 
681 		rt = vrf->rt6;
682 		dst_hold(&rt->dst);
683 	}
684 
685 	return (struct dst_entry *)rt;
686 }
687 #endif
688 
689 static const struct l3mdev_ops vrf_l3mdev_ops = {
690 	.l3mdev_fib_table	= vrf_fib_table,
691 	.l3mdev_get_rtable	= vrf_get_rtable,
692 	.l3mdev_get_saddr	= vrf_get_saddr,
693 #if IS_ENABLED(CONFIG_IPV6)
694 	.l3mdev_get_rt6_dst	= vrf_get_rt6_dst,
695 #endif
696 };
697 
698 static void vrf_get_drvinfo(struct net_device *dev,
699 			    struct ethtool_drvinfo *info)
700 {
701 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
702 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
703 }
704 
705 static const struct ethtool_ops vrf_ethtool_ops = {
706 	.get_drvinfo	= vrf_get_drvinfo,
707 };
708 
709 static void vrf_setup(struct net_device *dev)
710 {
711 	ether_setup(dev);
712 
713 	/* Initialize the device structure. */
714 	dev->netdev_ops = &vrf_netdev_ops;
715 	dev->l3mdev_ops = &vrf_l3mdev_ops;
716 	dev->ethtool_ops = &vrf_ethtool_ops;
717 	dev->destructor = free_netdev;
718 
719 	/* Fill in device structure with ethernet-generic values. */
720 	eth_hw_addr_random(dev);
721 
722 	/* don't acquire vrf device's netif_tx_lock when transmitting */
723 	dev->features |= NETIF_F_LLTX;
724 
725 	/* don't allow vrf devices to change network namespaces. */
726 	dev->features |= NETIF_F_NETNS_LOCAL;
727 }
728 
729 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
730 {
731 	if (tb[IFLA_ADDRESS]) {
732 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
733 			return -EINVAL;
734 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
735 			return -EADDRNOTAVAIL;
736 	}
737 	return 0;
738 }
739 
740 static void vrf_dellink(struct net_device *dev, struct list_head *head)
741 {
742 	unregister_netdevice_queue(dev, head);
743 }
744 
745 static int vrf_newlink(struct net *src_net, struct net_device *dev,
746 		       struct nlattr *tb[], struct nlattr *data[])
747 {
748 	struct net_vrf *vrf = netdev_priv(dev);
749 
750 	if (!data || !data[IFLA_VRF_TABLE])
751 		return -EINVAL;
752 
753 	vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
754 
755 	dev->priv_flags |= IFF_L3MDEV_MASTER;
756 
757 	return register_netdevice(dev);
758 }
759 
760 static size_t vrf_nl_getsize(const struct net_device *dev)
761 {
762 	return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
763 }
764 
765 static int vrf_fillinfo(struct sk_buff *skb,
766 			const struct net_device *dev)
767 {
768 	struct net_vrf *vrf = netdev_priv(dev);
769 
770 	return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
771 }
772 
773 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
774 				 const struct net_device *slave_dev)
775 {
776 	return nla_total_size(sizeof(u32));  /* IFLA_VRF_PORT_TABLE */
777 }
778 
779 static int vrf_fill_slave_info(struct sk_buff *skb,
780 			       const struct net_device *vrf_dev,
781 			       const struct net_device *slave_dev)
782 {
783 	struct net_vrf *vrf = netdev_priv(vrf_dev);
784 
785 	if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
786 		return -EMSGSIZE;
787 
788 	return 0;
789 }
790 
791 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
792 	[IFLA_VRF_TABLE] = { .type = NLA_U32 },
793 };
794 
795 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
796 	.kind		= DRV_NAME,
797 	.priv_size	= sizeof(struct net_vrf),
798 
799 	.get_size	= vrf_nl_getsize,
800 	.policy		= vrf_nl_policy,
801 	.validate	= vrf_validate,
802 	.fill_info	= vrf_fillinfo,
803 
804 	.get_slave_size  = vrf_get_slave_size,
805 	.fill_slave_info = vrf_fill_slave_info,
806 
807 	.newlink	= vrf_newlink,
808 	.dellink	= vrf_dellink,
809 	.setup		= vrf_setup,
810 	.maxtype	= IFLA_VRF_MAX,
811 };
812 
813 static int vrf_device_event(struct notifier_block *unused,
814 			    unsigned long event, void *ptr)
815 {
816 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
817 
818 	/* only care about unregister events to drop slave references */
819 	if (event == NETDEV_UNREGISTER) {
820 		struct net_device *vrf_dev;
821 
822 		if (!netif_is_l3_slave(dev))
823 			goto out;
824 
825 		vrf_dev = netdev_master_upper_dev_get(dev);
826 		vrf_del_slave(vrf_dev, dev);
827 	}
828 out:
829 	return NOTIFY_DONE;
830 }
831 
832 static struct notifier_block vrf_notifier_block __read_mostly = {
833 	.notifier_call = vrf_device_event,
834 };
835 
836 static int __init vrf_init_module(void)
837 {
838 	int rc;
839 
840 	register_netdevice_notifier(&vrf_notifier_block);
841 
842 	rc = rtnl_link_register(&vrf_link_ops);
843 	if (rc < 0)
844 		goto error;
845 
846 	return 0;
847 
848 error:
849 	unregister_netdevice_notifier(&vrf_notifier_block);
850 	return rc;
851 }
852 
853 module_init(vrf_init_module);
854 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
855 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
856 MODULE_LICENSE("GPL");
857 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
858 MODULE_VERSION(DRV_VERSION);
859