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perf bench futex: Cache align the worker struct
[linux/fpc-iii.git] / drivers / net / vrf.c
blob85c271c70d42fd57983f9fba822fb93d097d4590
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 DRV_NAME "vrf"
41 #define DRV_VERSION "1.0"
42
43 #define FIB_RULE_PREF 1000 /* default preference for FIB rules */
44 static bool add_fib_rules = true;
45
46 struct net_vrf {
47 struct rtable __rcu *rth;
48 struct rtable __rcu *rth_local;
49 struct rt6_info __rcu *rt6;
50 struct rt6_info __rcu *rt6_local;
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 u64 rx_drps;
61 struct u64_stats_sync syncp;
62 };
63
64 static void vrf_rx_stats(struct net_device *dev, int len)
65 {
66 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
67
68 u64_stats_update_begin(&dstats->syncp);
69 dstats->rx_pkts++;
70 dstats->rx_bytes += len;
71 u64_stats_update_end(&dstats->syncp);
72 }
73
74 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
75 {
76 vrf_dev->stats.tx_errors++;
77 kfree_skb(skb);
78 }
79
80 static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
81 struct rtnl_link_stats64 *stats)
82 {
83 int i;
84
85 for_each_possible_cpu(i) {
86 const struct pcpu_dstats *dstats;
87 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
88 unsigned int start;
89
90 dstats = per_cpu_ptr(dev->dstats, i);
91 do {
92 start = u64_stats_fetch_begin_irq(&dstats->syncp);
93 tbytes = dstats->tx_bytes;
94 tpkts = dstats->tx_pkts;
95 tdrops = dstats->tx_drps;
96 rbytes = dstats->rx_bytes;
97 rpkts = dstats->rx_pkts;
98 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
99 stats->tx_bytes += tbytes;
100 stats->tx_packets += tpkts;
101 stats->tx_dropped += tdrops;
102 stats->rx_bytes += rbytes;
103 stats->rx_packets += rpkts;
104 }
105 return stats;
106 }
107
108 /* Local traffic destined to local address. Reinsert the packet to rx
109 * path, similar to loopback handling.
110 */
111 static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
112 struct dst_entry *dst)
113 {
114 int len = skb->len;
115
116 skb_orphan(skb);
117
118 skb_dst_set(skb, dst);
119 skb_dst_force(skb);
120
121 /* set pkt_type to avoid skb hitting packet taps twice -
122 * once on Tx and again in Rx processing
123 */
124 skb->pkt_type = PACKET_LOOPBACK;
125
126 skb->protocol = eth_type_trans(skb, dev);
127
128 if (likely(netif_rx(skb) == NET_RX_SUCCESS))
129 vrf_rx_stats(dev, len);
130 else
131 this_cpu_inc(dev->dstats->rx_drps);
132
133 return NETDEV_TX_OK;
134 }
135
136 #if IS_ENABLED(CONFIG_IPV6)
137 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
138 struct sk_buff *skb)
139 {
140 int err;
141
142 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
143 sk, skb, NULL, skb_dst(skb)->dev, dst_output);
144
145 if (likely(err == 1))
146 err = dst_output(net, sk, skb);
147
148 return err;
149 }
150
151 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
152 struct net_device *dev)
153 {
154 const struct ipv6hdr *iph = ipv6_hdr(skb);
155 struct net *net = dev_net(skb->dev);
156 struct flowi6 fl6 = {
157 /* needed to match OIF rule */
158 .flowi6_oif = dev->ifindex,
159 .flowi6_iif = LOOPBACK_IFINDEX,
160 .daddr = iph->daddr,
161 .saddr = iph->saddr,
162 .flowlabel = ip6_flowinfo(iph),
163 .flowi6_mark = skb->mark,
164 .flowi6_proto = iph->nexthdr,
165 .flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF,
166 };
167 int ret = NET_XMIT_DROP;
168 struct dst_entry *dst;
169 struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
170
171 dst = ip6_route_output(net, NULL, &fl6);
172 if (dst == dst_null)
173 goto err;
174
175 skb_dst_drop(skb);
176
177 /* if dst.dev is loopback or the VRF device again this is locally
178 * originated traffic destined to a local address. Short circuit
179 * to Rx path using our local dst
180 */
181 if (dst->dev == net->loopback_dev || dst->dev == dev) {
182 struct net_vrf *vrf = netdev_priv(dev);
183 struct rt6_info *rt6_local;
184
185 /* release looked up dst and use cached local dst */
186 dst_release(dst);
187
188 rcu_read_lock();
189
190 rt6_local = rcu_dereference(vrf->rt6_local);
191 if (unlikely(!rt6_local)) {
192 rcu_read_unlock();
193 goto err;
194 }
195
196 /* Ordering issue: cached local dst is created on newlink
197 * before the IPv6 initialization. Using the local dst
198 * requires rt6i_idev to be set so make sure it is.
199 */
200 if (unlikely(!rt6_local->rt6i_idev)) {
201 rt6_local->rt6i_idev = in6_dev_get(dev);
202 if (!rt6_local->rt6i_idev) {
203 rcu_read_unlock();
204 goto err;
205 }
206 }
207
208 dst = &rt6_local->dst;
209 dst_hold(dst);
210
211 rcu_read_unlock();
212
213 return vrf_local_xmit(skb, dev, &rt6_local->dst);
214 }
215
216 skb_dst_set(skb, dst);
217
218 /* strip the ethernet header added for pass through VRF device */
219 __skb_pull(skb, skb_network_offset(skb));
220
221 ret = vrf_ip6_local_out(net, skb->sk, skb);
222 if (unlikely(net_xmit_eval(ret)))
223 dev->stats.tx_errors++;
224 else
225 ret = NET_XMIT_SUCCESS;
226
227 return ret;
228 err:
229 vrf_tx_error(dev, skb);
230 return NET_XMIT_DROP;
231 }
232 #else
233 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
234 struct net_device *dev)
235 {
236 vrf_tx_error(dev, skb);
237 return NET_XMIT_DROP;
238 }
239 #endif
240
241 /* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
242 static int vrf_ip_local_out(struct net *net, struct sock *sk,
243 struct sk_buff *skb)
244 {
245 int err;
246
247 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
248 skb, NULL, skb_dst(skb)->dev, dst_output);
249 if (likely(err == 1))
250 err = dst_output(net, sk, skb);
251
252 return err;
253 }
254
255 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
256 struct net_device *vrf_dev)
257 {
258 struct iphdr *ip4h = ip_hdr(skb);
259 int ret = NET_XMIT_DROP;
260 struct flowi4 fl4 = {
261 /* needed to match OIF rule */
262 .flowi4_oif = vrf_dev->ifindex,
263 .flowi4_iif = LOOPBACK_IFINDEX,
264 .flowi4_tos = RT_TOS(ip4h->tos),
265 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF,
266 .daddr = ip4h->daddr,
267 };
268 struct net *net = dev_net(vrf_dev);
269 struct rtable *rt;
270
271 rt = ip_route_output_flow(net, &fl4, NULL);
272 if (IS_ERR(rt))
273 goto err;
274
275 if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
276 ip_rt_put(rt);
277 goto err;
278 }
279
280 skb_dst_drop(skb);
281
282 /* if dst.dev is loopback or the VRF device again this is locally
283 * originated traffic destined to a local address. Short circuit
284 * to Rx path using our local dst
285 */
286 if (rt->dst.dev == net->loopback_dev || rt->dst.dev == vrf_dev) {
287 struct net_vrf *vrf = netdev_priv(vrf_dev);
288 struct rtable *rth_local;
289 struct dst_entry *dst = NULL;
290
291 ip_rt_put(rt);
292
293 rcu_read_lock();
294
295 rth_local = rcu_dereference(vrf->rth_local);
296 if (likely(rth_local)) {
297 dst = &rth_local->dst;
298 dst_hold(dst);
299 }
300
301 rcu_read_unlock();
302
303 if (unlikely(!dst))
304 goto err;
305
306 return vrf_local_xmit(skb, vrf_dev, dst);
307 }
308
309 skb_dst_set(skb, &rt->dst);
310
311 /* strip the ethernet header added for pass through VRF device */
312 __skb_pull(skb, skb_network_offset(skb));
313
314 if (!ip4h->saddr) {
315 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
316 RT_SCOPE_LINK);
317 }
318
319 ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
320 if (unlikely(net_xmit_eval(ret)))
321 vrf_dev->stats.tx_errors++;
322 else
323 ret = NET_XMIT_SUCCESS;
324
325 out:
326 return ret;
327 err:
328 vrf_tx_error(vrf_dev, skb);
329 goto out;
330 }
331
332 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
333 {
334 switch (skb->protocol) {
335 case htons(ETH_P_IP):
336 return vrf_process_v4_outbound(skb, dev);
337 case htons(ETH_P_IPV6):
338 return vrf_process_v6_outbound(skb, dev);
339 default:
340 vrf_tx_error(dev, skb);
341 return NET_XMIT_DROP;
342 }
343 }
344
345 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
346 {
347 netdev_tx_t ret = is_ip_tx_frame(skb, dev);
348
349 if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
350 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
351
352 u64_stats_update_begin(&dstats->syncp);
353 dstats->tx_pkts++;
354 dstats->tx_bytes += skb->len;
355 u64_stats_update_end(&dstats->syncp);
356 } else {
357 this_cpu_inc(dev->dstats->tx_drps);
358 }
359
360 return ret;
361 }
362
363 #if IS_ENABLED(CONFIG_IPV6)
364 /* modelled after ip6_finish_output2 */
365 static int vrf_finish_output6(struct net *net, struct sock *sk,
366 struct sk_buff *skb)
367 {
368 struct dst_entry *dst = skb_dst(skb);
369 struct net_device *dev = dst->dev;
370 struct neighbour *neigh;
371 struct in6_addr *nexthop;
372 int ret;
373
374 skb->protocol = htons(ETH_P_IPV6);
375 skb->dev = dev;
376
377 rcu_read_lock_bh();
378 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
379 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
380 if (unlikely(!neigh))
381 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
382 if (!IS_ERR(neigh)) {
383 ret = dst_neigh_output(dst, neigh, skb);
384 rcu_read_unlock_bh();
385 return ret;
386 }
387 rcu_read_unlock_bh();
388
389 IP6_INC_STATS(dev_net(dst->dev),
390 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
391 kfree_skb(skb);
392 return -EINVAL;
393 }
394
395 /* modelled after ip6_output */
396 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
397 {
398 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
399 net, sk, skb, NULL, skb_dst(skb)->dev,
400 vrf_finish_output6,
401 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
402 }
403
404 /* set dst on skb to send packet to us via dev_xmit path. Allows
405 * packet to go through device based features such as qdisc, netfilter
406 * hooks and packet sockets with skb->dev set to vrf device.
407 */
408 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
409 struct sock *sk,
410 struct sk_buff *skb)
411 {
412 struct net_vrf *vrf = netdev_priv(vrf_dev);
413 struct dst_entry *dst = NULL;
414 struct rt6_info *rt6;
415
416 /* don't divert link scope packets */
417 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
418 return skb;
419
420 rcu_read_lock();
421
422 rt6 = rcu_dereference(vrf->rt6);
423 if (likely(rt6)) {
424 dst = &rt6->dst;
425 dst_hold(dst);
426 }
427
428 rcu_read_unlock();
429
430 if (unlikely(!dst)) {
431 vrf_tx_error(vrf_dev, skb);
432 return NULL;
433 }
434
435 skb_dst_drop(skb);
436 skb_dst_set(skb, dst);
437
438 return skb;
439 }
440
441 /* holding rtnl */
442 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
443 {
444 struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
445 struct rt6_info *rt6_local = rtnl_dereference(vrf->rt6_local);
446 struct net *net = dev_net(dev);
447 struct dst_entry *dst;
448
449 RCU_INIT_POINTER(vrf->rt6, NULL);
450 RCU_INIT_POINTER(vrf->rt6_local, NULL);
451 synchronize_rcu();
452
453 /* move dev in dst's to loopback so this VRF device can be deleted
454 * - based on dst_ifdown
455 */
456 if (rt6) {
457 dst = &rt6->dst;
458 dev_put(dst->dev);
459 dst->dev = net->loopback_dev;
460 dev_hold(dst->dev);
461 dst_release(dst);
462 }
463
464 if (rt6_local) {
465 if (rt6_local->rt6i_idev)
466 in6_dev_put(rt6_local->rt6i_idev);
467
468 dst = &rt6_local->dst;
469 dev_put(dst->dev);
470 dst->dev = net->loopback_dev;
471 dev_hold(dst->dev);
472 dst_release(dst);
473 }
474 }
475
476 static int vrf_rt6_create(struct net_device *dev)
477 {
478 int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE;
479 struct net_vrf *vrf = netdev_priv(dev);
480 struct net *net = dev_net(dev);
481 struct fib6_table *rt6i_table;
482 struct rt6_info *rt6, *rt6_local;
483 int rc = -ENOMEM;
484
485 /* IPv6 can be CONFIG enabled and then disabled runtime */
486 if (!ipv6_mod_enabled())
487 return 0;
488
489 rt6i_table = fib6_new_table(net, vrf->tb_id);
490 if (!rt6i_table)
491 goto out;
492
493 /* create a dst for routing packets out a VRF device */
494 rt6 = ip6_dst_alloc(net, dev, flags);
495 if (!rt6)
496 goto out;
497
498 dst_hold(&rt6->dst);
499
500 rt6->rt6i_table = rt6i_table;
501 rt6->dst.output = vrf_output6;
502
503 /* create a dst for local routing - packets sent locally
504 * to local address via the VRF device as a loopback
505 */
506 rt6_local = ip6_dst_alloc(net, dev, flags);
507 if (!rt6_local) {
508 dst_release(&rt6->dst);
509 goto out;
510 }
511
512 dst_hold(&rt6_local->dst);
513
514 rt6_local->rt6i_idev = in6_dev_get(dev);
515 rt6_local->rt6i_flags = RTF_UP | RTF_NONEXTHOP | RTF_LOCAL;
516 rt6_local->rt6i_table = rt6i_table;
517 rt6_local->dst.input = ip6_input;
518
519 rcu_assign_pointer(vrf->rt6, rt6);
520 rcu_assign_pointer(vrf->rt6_local, rt6_local);
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 /* Be paranoid, rather than too clever. */
556 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
557 struct sk_buff *skb2;
558
559 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
560 if (!skb2) {
561 ret = -ENOMEM;
562 goto err;
563 }
564 if (skb->sk)
565 skb_set_owner_w(skb2, skb->sk);
566
567 consume_skb(skb);
568 skb = skb2;
569 }
570
571 rcu_read_lock_bh();
572
573 nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
574 neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
575 if (unlikely(!neigh))
576 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
577 if (!IS_ERR(neigh))
578 ret = dst_neigh_output(dst, neigh, skb);
579
580 rcu_read_unlock_bh();
581 err:
582 if (unlikely(ret < 0))
583 vrf_tx_error(skb->dev, skb);
584 return ret;
585 }
586
587 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
588 {
589 struct net_device *dev = skb_dst(skb)->dev;
590
591 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
592
593 skb->dev = dev;
594 skb->protocol = htons(ETH_P_IP);
595
596 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
597 net, sk, skb, NULL, dev,
598 vrf_finish_output,
599 !(IPCB(skb)->flags & IPSKB_REROUTED));
600 }
601
602 /* set dst on skb to send packet to us via dev_xmit path. Allows
603 * packet to go through device based features such as qdisc, netfilter
604 * hooks and packet sockets with skb->dev set to vrf device.
605 */
606 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
607 struct sock *sk,
608 struct sk_buff *skb)
609 {
610 struct net_vrf *vrf = netdev_priv(vrf_dev);
611 struct dst_entry *dst = NULL;
612 struct rtable *rth;
613
614 rcu_read_lock();
615
616 rth = rcu_dereference(vrf->rth);
617 if (likely(rth)) {
618 dst = &rth->dst;
619 dst_hold(dst);
620 }
621
622 rcu_read_unlock();
623
624 if (unlikely(!dst)) {
625 vrf_tx_error(vrf_dev, skb);
626 return NULL;
627 }
628
629 skb_dst_drop(skb);
630 skb_dst_set(skb, dst);
631
632 return skb;
633 }
634
635 /* called with rcu lock held */
636 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
637 struct sock *sk,
638 struct sk_buff *skb,
639 u16 proto)
640 {
641 switch (proto) {
642 case AF_INET:
643 return vrf_ip_out(vrf_dev, sk, skb);
644 case AF_INET6:
645 return vrf_ip6_out(vrf_dev, sk, skb);
646 }
647
648 return skb;
649 }
650
651 /* holding rtnl */
652 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
653 {
654 struct rtable *rth = rtnl_dereference(vrf->rth);
655 struct rtable *rth_local = rtnl_dereference(vrf->rth_local);
656 struct net *net = dev_net(dev);
657 struct dst_entry *dst;
658
659 RCU_INIT_POINTER(vrf->rth, NULL);
660 RCU_INIT_POINTER(vrf->rth_local, NULL);
661 synchronize_rcu();
662
663 /* move dev in dst's to loopback so this VRF device can be deleted
664 * - based on dst_ifdown
665 */
666 if (rth) {
667 dst = &rth->dst;
668 dev_put(dst->dev);
669 dst->dev = net->loopback_dev;
670 dev_hold(dst->dev);
671 dst_release(dst);
672 }
673
674 if (rth_local) {
675 dst = &rth_local->dst;
676 dev_put(dst->dev);
677 dst->dev = net->loopback_dev;
678 dev_hold(dst->dev);
679 dst_release(dst);
680 }
681 }
682
683 static int vrf_rtable_create(struct net_device *dev)
684 {
685 struct net_vrf *vrf = netdev_priv(dev);
686 struct rtable *rth, *rth_local;
687
688 if (!fib_new_table(dev_net(dev), vrf->tb_id))
689 return -ENOMEM;
690
691 /* create a dst for routing packets out through a VRF device */
692 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
693 if (!rth)
694 return -ENOMEM;
695
696 /* create a dst for local ingress routing - packets sent locally
697 * to local address via the VRF device as a loopback
698 */
699 rth_local = rt_dst_alloc(dev, RTCF_LOCAL, RTN_LOCAL, 1, 1, 0);
700 if (!rth_local) {
701 dst_release(&rth->dst);
702 return -ENOMEM;
703 }
704
705 rth->dst.output = vrf_output;
706 rth->rt_table_id = vrf->tb_id;
707
708 rth_local->rt_table_id = vrf->tb_id;
709
710 rcu_assign_pointer(vrf->rth, rth);
711 rcu_assign_pointer(vrf->rth_local, rth_local);
712
713 return 0;
714 }
715
716 /**************************** device handling ********************/
717
718 /* cycle interface to flush neighbor cache and move routes across tables */
719 static void cycle_netdev(struct net_device *dev)
720 {
721 unsigned int flags = dev->flags;
722 int ret;
723
724 if (!netif_running(dev))
725 return;
726
727 ret = dev_change_flags(dev, flags & ~IFF_UP);
728 if (ret >= 0)
729 ret = dev_change_flags(dev, flags);
730
731 if (ret < 0) {
732 netdev_err(dev,
733 "Failed to cycle device %s; route tables might be wrong!\n",
734 dev->name);
735 }
736 }
737
738 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
739 {
740 int ret;
741
742 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL);
743 if (ret < 0)
744 return ret;
745
746 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
747 cycle_netdev(port_dev);
748
749 return 0;
750 }
751
752 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
753 {
754 if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
755 return -EINVAL;
756
757 return do_vrf_add_slave(dev, port_dev);
758 }
759
760 /* inverse of do_vrf_add_slave */
761 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
762 {
763 netdev_upper_dev_unlink(port_dev, dev);
764 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
765
766 cycle_netdev(port_dev);
767
768 return 0;
769 }
770
771 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
772 {
773 return do_vrf_del_slave(dev, port_dev);
774 }
775
776 static void vrf_dev_uninit(struct net_device *dev)
777 {
778 struct net_vrf *vrf = netdev_priv(dev);
779 struct net_device *port_dev;
780 struct list_head *iter;
781
782 vrf_rtable_release(dev, vrf);
783 vrf_rt6_release(dev, vrf);
784
785 netdev_for_each_lower_dev(dev, port_dev, iter)
786 vrf_del_slave(dev, port_dev);
787
788 free_percpu(dev->dstats);
789 dev->dstats = NULL;
790 }
791
792 static int vrf_dev_init(struct net_device *dev)
793 {
794 struct net_vrf *vrf = netdev_priv(dev);
795
796 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
797 if (!dev->dstats)
798 goto out_nomem;
799
800 /* create the default dst which points back to us */
801 if (vrf_rtable_create(dev) != 0)
802 goto out_stats;
803
804 if (vrf_rt6_create(dev) != 0)
805 goto out_rth;
806
807 dev->flags = IFF_MASTER | IFF_NOARP;
808
809 /* MTU is irrelevant for VRF device; set to 64k similar to lo */
810 dev->mtu = 64 * 1024;
811
812 /* similarly, oper state is irrelevant; set to up to avoid confusion */
813 dev->operstate = IF_OPER_UP;
814 netdev_lockdep_set_classes(dev);
815 return 0;
816
817 out_rth:
818 vrf_rtable_release(dev, vrf);
819 out_stats:
820 free_percpu(dev->dstats);
821 dev->dstats = NULL;
822 out_nomem:
823 return -ENOMEM;
824 }
825
826 static const struct net_device_ops vrf_netdev_ops = {
827 .ndo_init = vrf_dev_init,
828 .ndo_uninit = vrf_dev_uninit,
829 .ndo_start_xmit = vrf_xmit,
830 .ndo_get_stats64 = vrf_get_stats64,
831 .ndo_add_slave = vrf_add_slave,
832 .ndo_del_slave = vrf_del_slave,
833 };
834
835 static u32 vrf_fib_table(const struct net_device *dev)
836 {
837 struct net_vrf *vrf = netdev_priv(dev);
838
839 return vrf->tb_id;
840 }
841
842 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
843 {
844 return 0;
845 }
846
847 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
848 struct sk_buff *skb,
849 struct net_device *dev)
850 {
851 struct net *net = dev_net(dev);
852
853 nf_reset(skb);
854
855 if (NF_HOOK(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) < 0)
856 skb = NULL; /* kfree_skb(skb) handled by nf code */
857
858 return skb;
859 }
860
861 #if IS_ENABLED(CONFIG_IPV6)
862 /* neighbor handling is done with actual device; do not want
863 * to flip skb->dev for those ndisc packets. This really fails
864 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
865 * a start.
866 */
867 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
868 {
869 const struct ipv6hdr *iph = ipv6_hdr(skb);
870 bool rc = false;
871
872 if (iph->nexthdr == NEXTHDR_ICMP) {
873 const struct icmp6hdr *icmph;
874 struct icmp6hdr _icmph;
875
876 icmph = skb_header_pointer(skb, sizeof(*iph),
877 sizeof(_icmph), &_icmph);
878 if (!icmph)
879 goto out;
880
881 switch (icmph->icmp6_type) {
882 case NDISC_ROUTER_SOLICITATION:
883 case NDISC_ROUTER_ADVERTISEMENT:
884 case NDISC_NEIGHBOUR_SOLICITATION:
885 case NDISC_NEIGHBOUR_ADVERTISEMENT:
886 case NDISC_REDIRECT:
887 rc = true;
888 break;
889 }
890 }
891
892 out:
893 return rc;
894 }
895
896 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
897 const struct net_device *dev,
898 struct flowi6 *fl6,
899 int ifindex,
900 int flags)
901 {
902 struct net_vrf *vrf = netdev_priv(dev);
903 struct fib6_table *table = NULL;
904 struct rt6_info *rt6;
905
906 rcu_read_lock();
907
908 /* fib6_table does not have a refcnt and can not be freed */
909 rt6 = rcu_dereference(vrf->rt6);
910 if (likely(rt6))
911 table = rt6->rt6i_table;
912
913 rcu_read_unlock();
914
915 if (!table)
916 return NULL;
917
918 return ip6_pol_route(net, table, ifindex, fl6, flags);
919 }
920
921 static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
922 int ifindex)
923 {
924 const struct ipv6hdr *iph = ipv6_hdr(skb);
925 struct flowi6 fl6 = {
926 .daddr = iph->daddr,
927 .saddr = iph->saddr,
928 .flowlabel = ip6_flowinfo(iph),
929 .flowi6_mark = skb->mark,
930 .flowi6_proto = iph->nexthdr,
931 .flowi6_iif = ifindex,
932 };
933 struct net *net = dev_net(vrf_dev);
934 struct rt6_info *rt6;
935
936 rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex,
937 RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
938 if (unlikely(!rt6))
939 return;
940
941 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
942 return;
943
944 skb_dst_set(skb, &rt6->dst);
945 }
946
947 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
948 struct sk_buff *skb)
949 {
950 int orig_iif = skb->skb_iif;
951 bool need_strict;
952
953 /* loopback traffic; do not push through packet taps again.
954 * Reset pkt_type for upper layers to process skb
955 */
956 if (skb->pkt_type == PACKET_LOOPBACK) {
957 skb->dev = vrf_dev;
958 skb->skb_iif = vrf_dev->ifindex;
959 skb->pkt_type = PACKET_HOST;
960 goto out;
961 }
962
963 /* if packet is NDISC or addressed to multicast or link-local
964 * then keep the ingress interface
965 */
966 need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
967 if (!ipv6_ndisc_frame(skb) && !need_strict) {
968 skb->dev = vrf_dev;
969 skb->skb_iif = vrf_dev->ifindex;
970
971 skb_push(skb, skb->mac_len);
972 dev_queue_xmit_nit(skb, vrf_dev);
973 skb_pull(skb, skb->mac_len);
974
975 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
976 }
977
978 if (need_strict)
979 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
980
981 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
982 out:
983 return skb;
984 }
985
986 #else
987 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
988 struct sk_buff *skb)
989 {
990 return skb;
991 }
992 #endif
993
994 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
995 struct sk_buff *skb)
996 {
997 skb->dev = vrf_dev;
998 skb->skb_iif = vrf_dev->ifindex;
999
1000 /* loopback traffic; do not push through packet taps again.
1001 * Reset pkt_type for upper layers to process skb
1002 */
1003 if (skb->pkt_type == PACKET_LOOPBACK) {
1004 skb->pkt_type = PACKET_HOST;
1005 goto out;
1006 }
1007
1008 skb_push(skb, skb->mac_len);
1009 dev_queue_xmit_nit(skb, vrf_dev);
1010 skb_pull(skb, skb->mac_len);
1011
1012 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1013 out:
1014 return skb;
1015 }
1016
1017 /* called with rcu lock held */
1018 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1019 struct sk_buff *skb,
1020 u16 proto)
1021 {
1022 switch (proto) {
1023 case AF_INET:
1024 return vrf_ip_rcv(vrf_dev, skb);
1025 case AF_INET6:
1026 return vrf_ip6_rcv(vrf_dev, skb);
1027 }
1028
1029 return skb;
1030 }
1031
1032 #if IS_ENABLED(CONFIG_IPV6)
1033 /* send to link-local or multicast address via interface enslaved to
1034 * VRF device. Force lookup to VRF table without changing flow struct
1035 */
1036 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1037 struct flowi6 *fl6)
1038 {
1039 struct net *net = dev_net(dev);
1040 int flags = RT6_LOOKUP_F_IFACE;
1041 struct dst_entry *dst = NULL;
1042 struct rt6_info *rt;
1043
1044 /* VRF device does not have a link-local address and
1045 * sending packets to link-local or mcast addresses over
1046 * a VRF device does not make sense
1047 */
1048 if (fl6->flowi6_oif == dev->ifindex) {
1049 dst = &net->ipv6.ip6_null_entry->dst;
1050 dst_hold(dst);
1051 return dst;
1052 }
1053
1054 if (!ipv6_addr_any(&fl6->saddr))
1055 flags |= RT6_LOOKUP_F_HAS_SADDR;
1056
1057 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, flags);
1058 if (rt)
1059 dst = &rt->dst;
1060
1061 return dst;
1062 }
1063 #endif
1064
1065 static const struct l3mdev_ops vrf_l3mdev_ops = {
1066 .l3mdev_fib_table = vrf_fib_table,
1067 .l3mdev_l3_rcv = vrf_l3_rcv,
1068 .l3mdev_l3_out = vrf_l3_out,
1069 #if IS_ENABLED(CONFIG_IPV6)
1070 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1071 #endif
1072 };
1073
1074 static void vrf_get_drvinfo(struct net_device *dev,
1075 struct ethtool_drvinfo *info)
1076 {
1077 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1078 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1079 }
1080
1081 static const struct ethtool_ops vrf_ethtool_ops = {
1082 .get_drvinfo = vrf_get_drvinfo,
1083 };
1084
1085 static inline size_t vrf_fib_rule_nl_size(void)
1086 {
1087 size_t sz;
1088
1089 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1090 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1091 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1092
1093 return sz;
1094 }
1095
1096 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1097 {
1098 struct fib_rule_hdr *frh;
1099 struct nlmsghdr *nlh;
1100 struct sk_buff *skb;
1101 int err;
1102
1103 if (family == AF_INET6 && !ipv6_mod_enabled())
1104 return 0;
1105
1106 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1107 if (!skb)
1108 return -ENOMEM;
1109
1110 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1111 if (!nlh)
1112 goto nla_put_failure;
1113
1114 /* rule only needs to appear once */
1115 nlh->nlmsg_flags &= NLM_F_EXCL;
1116
1117 frh = nlmsg_data(nlh);
1118 memset(frh, 0, sizeof(*frh));
1119 frh->family = family;
1120 frh->action = FR_ACT_TO_TBL;
1121
1122 if (nla_put_u32(skb, FRA_L3MDEV, 1))
1123 goto nla_put_failure;
1124
1125 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1126 goto nla_put_failure;
1127
1128 nlmsg_end(skb, nlh);
1129
1130 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1131 skb->sk = dev_net(dev)->rtnl;
1132 if (add_it) {
1133 err = fib_nl_newrule(skb, nlh);
1134 if (err == -EEXIST)
1135 err = 0;
1136 } else {
1137 err = fib_nl_delrule(skb, nlh);
1138 if (err == -ENOENT)
1139 err = 0;
1140 }
1141 nlmsg_free(skb);
1142
1143 return err;
1144
1145 nla_put_failure:
1146 nlmsg_free(skb);
1147
1148 return -EMSGSIZE;
1149 }
1150
1151 static int vrf_add_fib_rules(const struct net_device *dev)
1152 {
1153 int err;
1154
1155 err = vrf_fib_rule(dev, AF_INET, true);
1156 if (err < 0)
1157 goto out_err;
1158
1159 err = vrf_fib_rule(dev, AF_INET6, true);
1160 if (err < 0)
1161 goto ipv6_err;
1162
1163 return 0;
1164
1165 ipv6_err:
1166 vrf_fib_rule(dev, AF_INET, false);
1167
1168 out_err:
1169 netdev_err(dev, "Failed to add FIB rules.\n");
1170 return err;
1171 }
1172
1173 static void vrf_setup(struct net_device *dev)
1174 {
1175 ether_setup(dev);
1176
1177 /* Initialize the device structure. */
1178 dev->netdev_ops = &vrf_netdev_ops;
1179 dev->l3mdev_ops = &vrf_l3mdev_ops;
1180 dev->ethtool_ops = &vrf_ethtool_ops;
1181 dev->destructor = free_netdev;
1182
1183 /* Fill in device structure with ethernet-generic values. */
1184 eth_hw_addr_random(dev);
1185
1186 /* don't acquire vrf device's netif_tx_lock when transmitting */
1187 dev->features |= NETIF_F_LLTX;
1188
1189 /* don't allow vrf devices to change network namespaces. */
1190 dev->features |= NETIF_F_NETNS_LOCAL;
1191
1192 /* does not make sense for a VLAN to be added to a vrf device */
1193 dev->features |= NETIF_F_VLAN_CHALLENGED;
1194
1195 /* enable offload features */
1196 dev->features |= NETIF_F_GSO_SOFTWARE;
1197 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM;
1198 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1199
1200 dev->hw_features = dev->features;
1201 dev->hw_enc_features = dev->features;
1202
1203 /* default to no qdisc; user can add if desired */
1204 dev->priv_flags |= IFF_NO_QUEUE;
1205 }
1206
1207 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
1208 {
1209 if (tb[IFLA_ADDRESS]) {
1210 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1211 return -EINVAL;
1212 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1213 return -EADDRNOTAVAIL;
1214 }
1215 return 0;
1216 }
1217
1218 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1219 {
1220 unregister_netdevice_queue(dev, head);
1221 }
1222
1223 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1224 struct nlattr *tb[], struct nlattr *data[])
1225 {
1226 struct net_vrf *vrf = netdev_priv(dev);
1227 int err;
1228
1229 if (!data || !data[IFLA_VRF_TABLE])
1230 return -EINVAL;
1231
1232 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1233
1234 dev->priv_flags |= IFF_L3MDEV_MASTER;
1235
1236 err = register_netdevice(dev);
1237 if (err)
1238 goto out;
1239
1240 if (add_fib_rules) {
1241 err = vrf_add_fib_rules(dev);
1242 if (err) {
1243 unregister_netdevice(dev);
1244 goto out;
1245 }
1246 add_fib_rules = false;
1247 }
1248
1249 out:
1250 return err;
1251 }
1252
1253 static size_t vrf_nl_getsize(const struct net_device *dev)
1254 {
1255 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1256 }
1257
1258 static int vrf_fillinfo(struct sk_buff *skb,
1259 const struct net_device *dev)
1260 {
1261 struct net_vrf *vrf = netdev_priv(dev);
1262
1263 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1264 }
1265
1266 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1267 const struct net_device *slave_dev)
1268 {
1269 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1270 }
1271
1272 static int vrf_fill_slave_info(struct sk_buff *skb,
1273 const struct net_device *vrf_dev,
1274 const struct net_device *slave_dev)
1275 {
1276 struct net_vrf *vrf = netdev_priv(vrf_dev);
1277
1278 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1279 return -EMSGSIZE;
1280
1281 return 0;
1282 }
1283
1284 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1285 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1286 };
1287
1288 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1289 .kind = DRV_NAME,
1290 .priv_size = sizeof(struct net_vrf),
1291
1292 .get_size = vrf_nl_getsize,
1293 .policy = vrf_nl_policy,
1294 .validate = vrf_validate,
1295 .fill_info = vrf_fillinfo,
1296
1297 .get_slave_size = vrf_get_slave_size,
1298 .fill_slave_info = vrf_fill_slave_info,
1299
1300 .newlink = vrf_newlink,
1301 .dellink = vrf_dellink,
1302 .setup = vrf_setup,
1303 .maxtype = IFLA_VRF_MAX,
1304 };
1305
1306 static int vrf_device_event(struct notifier_block *unused,
1307 unsigned long event, void *ptr)
1308 {
1309 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1310
1311 /* only care about unregister events to drop slave references */
1312 if (event == NETDEV_UNREGISTER) {
1313 struct net_device *vrf_dev;
1314
1315 if (!netif_is_l3_slave(dev))
1316 goto out;
1317
1318 vrf_dev = netdev_master_upper_dev_get(dev);
1319 vrf_del_slave(vrf_dev, dev);
1320 }
1321 out:
1322 return NOTIFY_DONE;
1323 }
1324
1325 static struct notifier_block vrf_notifier_block __read_mostly = {
1326 .notifier_call = vrf_device_event,
1327 };
1328
1329 static int __init vrf_init_module(void)
1330 {
1331 int rc;
1332
1333 register_netdevice_notifier(&vrf_notifier_block);
1334
1335 rc = rtnl_link_register(&vrf_link_ops);
1336 if (rc < 0)
1337 goto error;
1338
1339 return 0;
1340
1341 error:
1342 unregister_netdevice_notifier(&vrf_notifier_block);
1343 return rc;
1344 }
1345
1346 module_init(vrf_init_module);
1347 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1348 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1349 MODULE_LICENSE("GPL");
1350 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1351 MODULE_VERSION(DRV_VERSION);
Linux with added FPC-III support